A comprehensive lemongrass (Cymbopogon citratus) leaf dataset for agricultural research and disease prevention

This article introduces a dataset of 10,042 Lemongrass (Cymbopogon citratus) leaf images, captured with high quality camera of a mobile phone in real-world conditions. The dataset classifies leaves as "Dried," "Healthy," or "Unhealthy," making it useful for machine learning, agriculture research, and plant health analysis. We collected the plant leaves from the Vishwakarma University Pune herbal garden and the captured the images in diverse backgrounds, angles, and lighting conditions. The images underwent pre-processing, involving batch image resizing through FastStone Photo Resizer and subsequent operations for compatibility with pre-trained models using the 'preprocess_input' function in the Keras library. The significance of the Lemongrass Leaves Dataset was demonstrated through experiments using well-known pre-trained models, such as InceptionV3, Xception, and MobileNetV2, showcasing its potential to enhance machine learning model accuracy in Lemongrass leaf identification and disease detection. Our goal is to aid researchers, farmers, and enthusiasts in improving Lemongrass cultivation and disease prevention. Researchers can use this dataset to train machine learning models for leaf condition classification, while farmers can monitor their crop's health. Its authenticity and size make it valuable for projects enhancing Lemongrass cultivation, boosting crop yield, and preventing diseases. This dataset is a significant step toward sustainable agriculture and plant health management.

Biogenic synthesis of levofloxacin-loaded copper oxide nanoparticles using Cymbopogon citratus: A green approach for effective antibacterial applications

Despite the success of antibiotics in medicine, the treatment of bacterial infection is still challenging due to emerging resistance and suitable drug delivery system, therefore, innovative approaches focused on nanoparticles based antimicrobial drug delivery systems are highly desired. This research aimed to synthesize Cymbopogon citratus (C. citratus) aqueous extract-mediated copper oxide (CuO-Nps) conjugated with levofloxacin (LFX). The synthesized CuO NPs-LFX nano conjugate was confirmed by analysis using scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and infrared and ultraviolet/visible spectroscopy. Antibacterial activities were assessed in vitro through the agar well diffusion method against six bacterial strains of clinical relevance. CuO NPs confirmed by UV-Vis analysis absorption peak observed at 380 nm. TGA analysis showed 8.98% weight loss between the 400-800 ° C temperature range. The functional group's presence was confirmed by FTIR analysis. Spherical shape nanoparticles with an average particle size of 55 nm were recorded by FESEM. Results from agar well diffusion assay showed that CuO NPs-LFX prohibited the development of both gram-positive and gram-negative bacteria at all established concentrations, and the antibacterial propensity was more pronounced as compared to bare CuO NPs, Levofloxacin and C. citratus aqueous extract alone. The results showed that gram-negative bacteria are more susceptible to CuO NPs-LFX nano conjugate and at 10 μgmL-1 concentration, form a 10.1 mm zone of inhibition (ZOI), whereas gram-positive bacteria on the same concentration form 9.5 mm ZOI. LFX-loaded CuO NPs antibacterial activity was observed higher than plant extract, bare CuO NPs, and standard drug (Levofloxacin). This study provides a novel approach for the fabrication of biogenic CuO NPs with antibacterial drug levofloxacin and their usage as nano antibiotic carriers against pathogenic bacteria, especially antibiotic-resistant microbes.

Multi-biological activity assessment and phytochemical characterization of an aqueous extract of the Cymbopogon citratus grown in Palestine

BACKGROUND

Plants have historically been a rich source of medicinal compounds, with many modern pharmaceuticals derived from botanical origins. In contemporary healthcare, there is a resurgence in utilizing botanical substances as recognized medicinal agents. This study delved into understanding the phytochemical makeup and the multifaceted biological activities of an aqueous extract from Cymbopogon citratus (C. citratus). The investigated activities were its effect on AMPA receptors, antioxidant capacity, anti-lipase, anti-α-amylase actions, cytotoxicity, and antimicrobial properties.

METHODS

The extract of C. citratus received a comprehensive investigation, which included the study of its phytochemical composition, assessment of its antioxidant and anti-lipase properties, evaluation of its capacity to inhibit α-amylase, analysis of its impact on cell viability, and assessment of its antimicrobial activity. The approaches are used to clarify the complex physiological and biochemical characteristics.

RESULTS

The results were compelling; receptor kinetics had a marked impact, notably on the GluA2 subunit. Regarding its medicinal potential, the extract demonstrated potent antioxidant and anti-diabetic activities with IC50 values of 15.13 and 101.14 µg/mL, respectively. Additionally, it displayed significant inhibitory effects on the lipase enzyme and showed cytotoxicity against the Hep3B cancer cell line, with IC50 values of 144.35 and 148.37 µg/mL. In contrast, its effects on the normal LX-2 cell line were minimal, indicating selectivity.

CONCLUSION

The aqueous extract of C. citratus shows promising therapeutic properties. The findings advocate for further research into its compounds for potential isolation, purification, and in-depth pharmacological studies, especially in areas like nervous system disorders, diabetes, obesity, and combating oxidative stress.

In silico modeling revealed phytomolecules derived from Cymbopogon citratus (DC.) leaf extract as promising candidates for malaria therapy

The emergence of varying levels of resistance to currently available antimalarial drugs significantly threatens global health. This factor heightens the urgency to explore bioactive compounds from natural products with a view to discovering and developing newer antimalarial drugs with novel mode of actions. Therefore, we evaluated the inhibitory effects of sixteen phytocompounds from Cymbopogon citratus leaf extract against Plasmodium falciparum drug targets such as P. falciparum circumsporozoite protein (PfCSP), P. falciparum merozoite surface protein 1 (PfMSP1) and P. falciparum erythrocyte membrane protein 1 (PfEMP1). In silico approaches including molecular docking, pharmacophore modeling and 3D-QSAR were adopted to analyze the inhibitory activity of the compounds under consideration. The molecular docking results indicated that a compound swertiajaponin from C. citratus exhibited a higher binding affinity (-7.8 kcal/mol) to PfMSP1 as against the standard artesunate-amodiaquine (-6.6 kcal/mol). Swertiajaponin also formed strong hydrogen bond interactions with LYS29, CYS30, TYR34, ASN52, GLY55 and CYS28 amino acid residues. In addition, quercetin another compound from C. citratus exhibited significant binding energies -6.8 and -8.3 kcal/mol with PfCSP and PfEMP1, respectively but slightly lower than the standard artemether-lumefantrine with binding energies of -7.4 kcal/mol against PfCSP and -8.7 kcal/mol against PfEMP1. Overall, the present study provides evidence that swertiajaponin and other phytomolecules from C. citratus have modulatory properties toward P. falciparum drug targets and thus may warrant further exploration in early drug discovery efforts against malaria. Furthermore, these findings lend credence to the folkloric use of C. citratus for malaria treatment.Communicated by Ramaswamy H. Sarma.

Biosynthesis of Al2 O3 and europium-doped Al2 O3 nanoparticle using Cymbopogon citratus (lemongrass) extract and its antibacterial property

Cymbopogon citratus-mediated pure aluminium oxide (Al2 O3 ) and europium (Eu)-doped Al2 O3 with different amounts of metal ion were prepared using a green synthesis method. Synthesised nanoparticles were characterised by ultraviolet (UV)-visible spectroscopy, photoluminescence (PL), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Synthesis of nanoparticles is confirmed by using UV-visible spectroscopy showing maximum absorption at 411 and 345 nm for Al2 O3 and Eu-doped Al2 O3 , respectively. The antibacterial activity of prepared nanoparticles was evaluated against Pseudomonas aeruginosa, Streptococcus aureus, Escherichia coli and Klebsiella pneumoniae using a well-diffusion technique. The effect of pure Al2 O3 and Eu-doped nanoparticles shows excellent results against P. aeruginosa, S. aureus, E. coli and K. pneumoniae.

The Cytokinins BAP and 2-iP Modulate Different Molecular Mechanisms on Shoot Proliferation and Root Development in Lemongrass (Cymbopogon citratus)

The known activities of cytokinins (CKs) are promoting shoot multiplication, root growth inhibition, and delaying senescence. 6-Benzylaminopurine (BAP) has been the most effective CK to induce shoot proliferation in cereal and grasses. Previously, we reported that in lemongrass (Cymbopogon citratus) micropropagation, BAP 10 µM induces high shoot proliferation, while the natural CK 6-(γ,γ-Dimethylallylamino)purine (2-iP) 10 µM shows less pronounced effects and developed rooting. To understand the molecular mechanisms involved, we perform a protein-protein interaction (PPI) network based on the genes of Brachypodium distachyon involved in shoot proliferation/repression, cell cycle, stem cell maintenance, auxin response factors, and CK signaling to analyze the molecular mechanisms in BAP versus 2-iP plants. A different pattern of gene expression was observed between BAP- versus 2-iP-treated plants. In shoots derived from BAP, we found upregulated genes that have already been demonstrated to be involved in de novo shoot proliferation development in several plant species; CK receptors (AHK3, ARR1), stem cell maintenance (STM, REV and CLV3), cell cycle regulation (CDKA-CYCD3 complex), as well as the auxin response factor (ARF5) and CK metabolism (CKX1). In contrast, in the 2-iP culture medium, there was an upregulation of genes involved in shoot repression (BRC1, MAX3), ARR4, a type A-response regulator (RR), and auxin metabolism (SHY2).

Eco-friendly approaches of zinc oxide and silver nitrate nanoparticles along with plant extracts against Spodoptera litura (Fabricius) under laboratory conditions

The tobacco cutworm (Spodoptera litura) is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar S. litura larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from Cymbopogon citratus. In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against S. litura when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.

Biological Activity of Biosynthesized Silver Nanoaggregates Prepared from the Aqueous Extract of Cymbopogon citratus against Candida spp

Cymbopogon citratus is commonly used in folk medicine for the treatment of nervous and gastrointestinal disturbances and other medical issues because of its potent antioxidant capacity. The current study evaluated the anti-candida effects of silver nanoparticles (AgNPs) synthesized from an aqueous extract of C. citratus against different Candida spp. The aqueous extract was prepared from the fresh leaves of C. citratus. The silver nanoparticles (AgNPs) were prepared and validated by UV spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), and zeta size analysis. C. albicans, C. krusei, C. parapsilosis, C. tropicalis, C. famata, C. rhodotorula, and C. glabrata were used in the antifungal assay. Microscopical imaging were used to investigate the different morphological changes induced by treatment. FTIR spectrum confirmed the existence of various functional groups of biomolecules capping the nanoparticles. The average particle size of synthesized AgNPs was 100.6 nm by zeta-sizer and 0.012 to 0.059 mm by TEM. In the antifungal assay, AgNPs aggregates induced significant inhibition of the growth of all species (p < 0.05) compared to the control and the biofilm maturation in C. famata and C. albicans. These considerable antifungal activities might lead to the development of appropriate alternative remedy for the treatment of fungal infections.

Oxidative stability and physicochemical changes of dark chocolates with essential oils addition

This research aimed to evaluate the oxidative stability and rheological properties of dark chocolates with the addition of essential oils (EO) of Cymbopogon citratus, Pimpinella anisum, and Mintostachys mollis. For this purpose, before the inclusion in chocolates, the EO were chemically characterized to identify the most important volatile compounds. We added essential oils of P. anisum, C. citratus and M. mollis to dark chocolates (cocoa 70%) at doses of 10, 12 and 14 μL per 500 g, separately. These chocolates were evaluated for oxidative activity, hardness, microstructure, rheological and melting properties and antioxidant capacity. It was found that C. citratus EO (10 μL/500 g of chocolate) improve the oxidative stability of the chocolates at 90 days of storage at 25 °C (230 meq O₂/kg), while higher concentrations promote lipid oxidation. The incorporation of essential oils improves the antioxidant capacity, likewise, it changes the rheological, thermal, and microstructural properties. Therefore, essential oils can improve the physicochemical characteristics of dark chocolates allowing greater stability in oxidative fat and thus increase the shelf life.

First Report on the Synergistic Interaction between Essential Oils against the Pinewood Nematode Bursaphelenchus xylophilus

Control of the pinewood nematode (PWN), the causal agent of pine wilt disease, can be achieved through the trunk injection of nematicides; however, many pesticides have been linked to environmental and human health concerns. Essential oils (EOs) are suitable alternatives due to their biodegradability and low toxicity to mammals. These complex mixtures of plant volatiles often display multiple biological activities and synergistic interactions between their compounds. The present work profiled the toxicity of eight EOs against the PWN in comparison to their 1:1 mixtures, to screen for successful synergistic interactions. Additionally, the main compounds of the most synergistic mixtures were characterized for their predicted environmental fate and toxicity to mammals in comparison to emamectin benzoate, a commercial nematicide used against PWN. The mixtures of Cymbopogon citratus with Mentha piperita and of Foeniculum vulgare with Satureja montana EOs showed the highest activities, with half-maximal effective concentrations (EC₅₀) of 0.09 and 0.05 µL/mL, respectively. For these, complete PWN mortality was reached after only ca. 15 min or 2 h of direct contact, respectively. Their major compounds had a higher predicted affinity to air and water environmental compartments and are reported to have very low toxicity to mammals, with low acute oral and dermal toxicities. In comparison, emamectin benzoate showed lower nematicidal activity, a higher affinity to the soil and sediments environmental compartments and higher reported oral and dermal toxicity to mammals. Overall, uncovering synergistic activities in combinations of EOs from plants of different families may prove to be a source of biopesticides with optimized toxicity against PWNs.

Cymbopogon citratus Essential Oil: Extraction, GC-MS, Phytochemical Analysis, Antioxidant Activity, and In Silico Molecular Docking for Protein Targets Related to CNS

This study analyzed the chemical composition of Cymbopogon citratus essential oil from Puebla, México, assessed its antioxidant activity, and evaluated in silico protein-compound interactions related to central nervous system (CNS) physiology. GC-MS analysis identified myrcene (8.76%), Z-geranial (27.58%), and E-geranial (38.62%) as the main components, with 45 other compounds present, which depends on the region and growing conditions. DPPH and Folin-Ciocalteu assays using the leaves extract show a promising antioxidant effect (EC₅₀ = 48.5 µL EO/mL), reducing reactive oxygen species. The bioinformatic tool SwissTargetPrediction (STP) shows 10 proteins as potential targets associated with CNS physiology. Moreover, protein-protein interaction diagrams suggest that muscarinic and dopamine receptors are related to each other through a third party. Molecular docking reveals that Z-geranial has higher binding energy than M1 commercial blocker and blocks M2, but not M4 muscarinic acetylcholine receptors, whereas β-pinene and myrcene block M1, M2, and M4 receptors. These actions may positively affect cardiovascular activity, memory, Alzheimer's disease, and schizophrenia. This study highlights the significance of understanding natural product interactions with physiological systems to uncover potential therapeutic agents and advanced knowledge on their benefits for human health.

Validation of Broth Macrodilution Volatilization Method for Testing of Essential Oils in Liquid and Vapor Phase: Chemical Composition, Cytotoxicity, and Antibacterial Effect of Indian Medicinal Plants against Pneumonia-Causing Pathogens

Essential oils (EOs) have great potential in inhalation therapy for the treatment of respiratory infections. However, innovative methods for evaluation of antimicrobial activity of their vapors are still needed. The current study reports validation of the broth macrodilution volatilization method for assessment of the antibacterial properties of EOs and shows the growth-inhibitory effect of Indian medicinal plants against pneumonia-causing bacteria in liquid and vapor phase. Among all samples tested, Trachyspermum ammi EO exhibits the strongest antibacterial effect against Haemophilus influenzae, with minimum inhibitory concentrations of 128 and 256 µg/mL in the liquid and vapor phases, respectively. Furthermore, Cyperus scariosus EO is found to be nontoxic to normal lung fibroblasts assessed by modified thiazolyl blue tetrazolium bromide assay. Chemical analysis performed using gas chromatography-mass spectrometry identified α-citral, cyperotundone, and thymol as the main constituents of Cymbopogon citratus, C. scariosus, and T. ammi EOs, respectively. In addition, β-cymene is identified as the major compound of T. ammi EO vapors when analyzed using solid-phase microextraction and gas-tight syringe sampling techniques. This study demonstrates the validity of the broth macrodilution volatilization method for antimicrobial screening of volatile compounds in the vapor phase and suggests the therapeutic potential of Indian medicinal plants in inhalation therapy.

Anti-bacterial activity of Cymbopogon citratus nanoparticles against Vibrio species infecting aquatic organisms

The presence of Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio harveyi in aquatic organisms causes vibriosis, leading to their significant mortality. The efficacy of antibiotic treatment is reduced due to increasing antibiotic resistance. As a result, novel therapeutic agents are increasingly needed to treat outbreak of such diseases in aquatic organisms and humans. This study focuses on utilizing the bioactive compounds of Cymbopogon citratus as they are rich in a variety of secondary metabolites which promotes growth, natural immune response and disease resistance against pathogenic bacteria in various ecosystems. In silico studies were performed to evaluate the binding potential of the bioactive compounds against targeted protein beta - lactamase in Vibrio parahaemolyticus and metallo - beta - lactamase in V. alginolyticus via molecular docking. Cymbopogon citratus nanoparticles (CcNps) were synthesized, characterized and toxicity studies were performed by using Vigna radiata, and Artemia nauplii at different concentrations of Cymbopogon citratus nanoparticles. The results revealed that the synthesized nanoparticles were non-ecotoxic and act as potential growth promoters in plants. The antibacterial activity of synthesized Cymbopogon citratus was evaluated using agar well diffusion method. MIC, MBC, and biofilm assays performed by using different concentrations of synthesized nanoparticles. Thus, it was proved that Cymbopogon citratus nanoparticles showed better antibacterial activity against Vibrio species.

Cymbopogon citratus and Citral Overcome Doxorubicin Resistance in Cancer Cells via Modulating the Drug's Metabolism, Toxicity, and Multidrug Transporters

Multidrug resistance (MDR) is the major complex mechanism that causes the failure of chemotherapy, especially with drugs of natural origin such as doxorubicin (DOX). Intracellular drug accumulation and detoxification are also involved in cancer resistance by reducing the susceptibility of cancer cells to death. This research aims to identify the volatile composition of Cymbopogon citratus (lemon grass; LG) essential oil and compare the ability of LG and its major compound, citral, to modulate MDR in resistant cell lines. The composition of LG essential oil was identified using gas chromatography mass spectrometry (GC-MS). In addition, a comparison of the modulatory effects of LG and citral, performed on breast (MCF-7/ADR), hepatic (HepG-2/ADR), and ovarian (SKOV-3/ADR) MDR cell lines, were compared to their parent sensitive cells using the MTT assay, ABC transporter function assays, and RT-PCR. Oxygenated monoterpenes (53.69%), sesquiterpene hydrocarbons (19.19%), and oxygenated sesquiterpenes (13.79%) made up the yield of LG essential oil. α-citral (18.50%), β-citral (10.15%), geranyl acetate (9.65%), ylangene (5.70), δ-elemene (5.38%), and eugenol (4.77) represent the major constituents of LG oil. LG and citral (20 μg/mL) synergistically increased DOX cytotoxicity and lowered DOX dosage by >3-fold and >1.5-fold, respectively. These combinations showed synergism in the isobologram and CI < 1. DOX accumulation or reversal experiment confirmed that LG and citral modulated the efflux pump function. Both substances significantly increased DOX accumulation in resistant cells compared to untreated cells and verapamil (the positive control). RT-PCR confirmed that LG and citral targeted metabolic molecules in resistant cells and significantly downregulated PXR, CYP3A4, GST, MDR1, MRP1, and PCRP genes. Our results suggest a novel dietary and therapeutic strategy combining LG and citral with DOX to overcome multidrug resistance in cancer cells. However, these results should be confirmed by additional animal experiments before being used in human clinical trials.

A comprehensive approach to chitosan-gelatine edible coating with β-cyclodextrin/lemongrass essential oil inclusion complex - Characterization and food application

Biopolymer-based films present an ideal matrix for the incorporation of active substances such as antimicrobial agents, giving active packaging a framework of green chemistry and a step forward in food packaging technology. The chitosan-gelatine active coating has been prepared using lemongrass oil as an antimicrobial compound applying a different approach. Instead of surfactants, to achieve compatibilization of compounds, β-cyclodextrin was used to encapsulate lemongrass oil. The antimicrobial effect was assessed using the dip-coating method on freshly harvested cherry tomatoes artificially contaminated by Penicillium aurantiogriseum during 20 days of cold storage. According to the evaluation of the antimicrobial effect of coating formulation on cherry tomato samples, which was mathematically assessed by predictive kinetic models and digital imaging, the applied coating formulation was found to be very effective since the development of fungal contamination for active-coated samples was observed for 20 days.

(Lamiaceae), and Zingiber officinale Roscoe (Zingiberaceae)

Essential oils (EOs) and their vapour phase of Curcuma longa (Zingiberaceae), Cymbopogon citratus (Poaceae), Ocimum campechianum (Lamiaceae), and Zingiber officinale (Zingiberaceae) of cultivated plants grown in an Amazonian Ecuador area were chemically characterised by Gas Chromatography-Flame Ionization Detector (GC-FID), Gas Chromatography-Mass Spectrometry (GC-MS), and Head Space-Gas Chromatograph-Flame Ionization Detector-Mass Spectrometry (HS-GC-FID-MS).figure The EOs analyses led to the identification of 25 compounds for C. longa (99.46% of the total; ar-turmerone: 23.35%), 18 compounds for C. citratus (99.59% of the total; geraniol: 39.43%), 19 compounds for O. campechianum (96.24% of the total; eugenol: 50.97%), and 28 for Z. officinale (98.04% of the total; α-Zingiberene: 15.45%). The Head Space fractions (HS) revealed C. longa mainly characterised by limonene and 1,8-cineole (37.35%) and α-phellandrene (32.33%); Z. officinale and C. citratus showed camphene (50.39%) and cis-Isocitral (15.27%) as the most abundant compounds, respectively. O. campechianum EO revealed a higher amount of sesquiterpenes (10.08%), mainly characterised by E-caryophyllene (4.95%), but monoterpene fraction remained the most abundant (89.94%). The EOs were tested for antioxidant, antimicrobial, and mutagen-protective properties and compared to the Thymus vulgaris EO as a positive reference. O. campechianum EO was the most effective in all the bioactivities checked. Similar results emerged from assaying the bioactivity of the vapour phase of O. campechianum EO. The antioxidant and antimicrobial activity evaluation of O. campechianum EO were repeated through HP-TLC bioautography assay, pointing out eugenol as the lead compound for bioactivity. The mutagen-protective evaluation checked through Ames's test properly modified evidenced a better capacity of O. campechianum EO compared with the other EOs, reducing the induced mutagenicity at 0.1 mg/plate. However, even with differences in efficacy, the overall results suggest important perspectives for the functional use of the four studied EOs.

Extracts to Fermented Orange Beverage: Sensory Evaluation, Physicochemical Characterization, and Prediction of Toxic Risks and Biological Activity In Silico

Fermentation is an important tool in producing functional beverages through agro-industrial wastes, and medicinal and aromatic plants due to the specific content of bioactive molecules. Therefore, this study evaluated the contribution of Matricaria recutita (chamomile), Cymbopogon citratus (lemongrass), or Mentha piperita (peppermint) extracts to the phytochemical profile and potential biological effects of a functional fermented orange beverage in vitro and in silico. The concentrations of aromatic herbal extracts that yielded the best sensory performance for fermented beverages were selected for analyses that involved characterizing the fermented beverages. The beverages that received the extracts (2%) had the highest phenolic and flavonoid content and antioxidant potential compared to the control. Hesperidin (124-130 mg L^-1), narirutin (66-70 mg L^-1), chlorogenic (11-16 mg L^-1), caffeic (5.3-5.5 mg L^-1), and ferulic (1-1.7 mg L^-1) acids were found in the different formulations. The in silico analysis suggested that the evaluated compounds do not present a toxicity risk (mutagenicity, carcinogenicity, hepatotoxicity, and ability to penetrate the blood-brain barrier). Additionally, they can contribute to the biological effects of therapeutic importance, such as antioxidant, gastroprotective, and anti-ulcerative properties, and the Mentha piperita L. extract presented the greatest potential among the evaluated herbs for use in functional fermented beverages.

Enhanced antimicrobial and antioxidant capacity of Thymus vulgaris, Lippia sidoides, and Cymbopogon citratus emulsions when combined with mannosylerythritol a lipid biosurfactant

Essential oils (EOs) are natural and effective agents for controlling microorganisms which cause biodeterioration and disease. However, their application is hampered/restricted due to hydrophobicity and rapid vaporization of these compounds. Encapsulation technology provides an effective approach to maintain EO stabilization and prevent the loss of volatile ingredients. Meanwhile, using a synthetic surfactant is seen as counter-productive; therefore, a natural biosurfactant is more reasonable and can potentially increase activity due to its other biological proprieties. This work aims to evaluate the mannosylerythritol lipid (MEL) biosurfactant combined with Thymus vulgaris, Lippia sidoides, and Cymbopogon citratus essential oil emulsions (O/W) and evaluate its antimicrobial and antioxidant capacity. The biosurfactant MEL demonstrated activity against Bacillus subtilis and Penicillium sp. After emulsification, the antimicrobial activity of Thymus vulgaris and Lippia sidoides was increased against Escherichia coli (500 µg/mL), Staphylococcus aureus (600 µg/mL), Bacillus subtilis (120 µg/mL), Pseudomonas aeruginosa (1500 µg/mL), Penicillium sp. (62.25 µg/mL), Aspergillus flavus (250 µg/mL), Fusarium oxysporum (100 and 250 µg/mL), and Candida albicans (125 and 250 µg/mL). We report that emulsions prepared with MEL have high inhibitory activity, maintain the active concentration, and increase antioxidant capacity by 7.33% (Thymus vulgaris), 13.71% (Lippia sidoides), and 3.15% (Cymbopogon citratus).

of North-Western Himalaya

Cymbopogon citratus (DC.) Stapf is an aromatic perennial herb of Gramineae (Poaceae) family and is known for its application in food and healthcare industry. The present study aimed to evaluate anti-inflammatory and antioxidant potential of C. citratus essential oil (CEO) through in vitro and in silico studies. Chemical characterization of CEO was done using Gas chromatography-mass spectrophotometry (GC-MS) method. In vitro antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric ion reducing antioxidant power (FRAP) assays, while egg albumin denaturation method was used to evaluate in vitro anti-inflammatory activity of CEO. Molecular docking investigation of major phytocompounds of CEO was done using Autodock vina software against human peroxiredoxin 5 (PDB ID: 1HD2) and human cyclooxygenase 2 (PDB ID: 5IKQ) proteins, which were further analyzed through molecular dynamics (MD) simulation using YASARA. GC-MS analysis of CEO showed the presence of geranial (48%) neral (34.04%), β-myrcene (9.77%), geraniol (1.88%), linalool (0.84%), isogeranial (0.81%), β-caryophyllene (0.80%), D-limonene (0.51%) as major constituents. CEO showed significant antioxidant activity with DPPH (IC₅₀-47.53 ± 2.16 µg/ml), FRAP (IC₅₀-30.7 ± 0.31 µM), and ABTS assays (IC₅₀-27.87 ± 0.09 µg/ml). CEO also exhibited significant in-vitro anti-inflammatory activity with IC₅₀-29.71 ± 1.95 µg/ml as compared to that of Diclofenac sodium (IC₅₀-36.52 ± 1.95 µg/ml). Molecular docking revealed that β-caryophyllene showed considerable binding potential with human peroxiredoxin 5 receptor (-6.0 kcal/mol) and human cyclooxygenase 2 receptor (-10.1 kcal/mol). Further, MD simulations demonstrated considerable and stable interactions of β-caryophyllene with 1HD2 and 5IKQ proteins up to 100 ns. Drug-likeness and ADME/T features also showed that β-caryophyllene can be used as a potential candidate to replace the synthetic anti-inflammatory drugs with side effects and also act as natural antioxidants.Communicated by Ramaswamy H. Sarma.

The potency of herbal extracts and its green synthesized nanoparticle formulation as antibacterial agents against Streptococcus mutans associated biofilms

This study aims to determine the effects of the extracts of Streblus asper, Cymbopogon citratus, Syzygium aromaticum and its formulation of green synthesized silver nanoparticle (AgNPs) on Streptococcus mutans growth and biofilm formation. The ethanolic extracts of S. asper, C. citratus, S. aromaticum, and a mix of the three herbs demonstrated antibacterial activity against S. mutans isolates by reducing bacterial biofilm formation and decreasing bacterial cell surface hydrophobicity. The formulated AgNPs from the ethanolic extracts could enhance the antibacterial activities of the plant extracts. Molecular docking found the best interaction between luteolin isolated from C. citratus and glucosyltransferase protein (GtfB), assuming the promising anti-biofilm activity. The scanning electron microscopy revealed morphological changes in the biofilm structure and a significant decrease in the biofilm area of the AgNPs treated. The study suggested that the extracts and its application could be used as natural alternative agents with multi-action against S. mutans infections.

Toxicity, Behavioral Effects, and Chitin Structural Chemistry of Reticulitermes flaviceps Exposed to Cymbopogon citratus EO and Its Major Constituent Citral

Botanical pesticides are considered the most promising alternative to synthetic pesticides, considering their less negative impacts on the environment and human health. Here, we analyzed the components of lemongrass Cymbopogon citratus essential oil (EO) and evaluated its vapor activity against Reticulitermes flaviceps, in terms of the walking and gripping abilities of workers. In addition, the effects of lemongrass EO and its major component on the cuticular content and structure of chitin in termites were also observed. Our results indicate that cis-citral (36.51%) was the main constituent of lemongrass. In the vapor toxicity assay, the LC₅₀ values of lemongrass EO and citral were 0.328 and 0.177 μL/L, respectively. When worker antennae were treated with lemongrass EO and citral, their walking and gripping capabilities were significantly inhibited. In addition, the cuticular content, thermal stability, and crystallinity of chitin in the termites were decreased after treatment with citral. Collectively, this study provides a basis for developing and utilizing lemongrass and citral as a new environment-friendly insecticide resource to control R. flaviceps.

Extraction of essential oils from tea tree (Melaleuca alternifolia) and lemon grass (Cymbopogon citratus) using betaine-based deep eutectic solvent (DES)

INTRODUCTION

The essential oils of tea tree (Melaleuca alternifolia) leaves mainly contain eucalyptol, α-terpinene, γ -terpinene, and terpinen-4-ol and have anti-bacterial, anti-fungal, anti-infective, and anti-inflammatory actions. The essential oils of lemon grass (Cymbopogon citratus) leaves mainly contain neral, geranial, and geraniol and have anti-microbial and anti-fungal activities and hypocholesterolemic effect.

OBJECTIVES

The present study describes the use of low-toxicity solvents called betaine-based deep eutectic solvents (DESs) for efficient extraction of essential oils from tea tree and lemon grass. H₂ O and EtOH were used for extraction as control methods.

METHODOLOGY

Quantitative analysis was performed using gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring mode. Scanning electron micrography (SEM) and antioxidant assays for extracted samples were also conducted.

RESULTS

The results indicated that extraction for tea tree using betaine/sucrose (molar ratio 2:1) improved the yields of terpinolene and eucalyptol 2.5- and 1.9-fold, respectively, compared with the control method. In lemon grass, extraction using betaine/sucrose (molar ratio 2:1) improved the yields of neral and geranial 1.9- and 1.7-fold, respectively, compared with the control method.

CONCLUSION

These results demonstrated the effective extraction of essential oils from plant leaves under milder conditions than those needed for the conventional methods. The environmentally benign DESs for the extraction would be applicable to the food and cosmetic industries.

Genetic diversity analysis for wild and cultivated accessions of Cymbopogon citratus (D.C.) Stapf using phytochemical and molecular markers

Background

Genetic diversity is being lost because of increasing urbanization and decreasing cultivation land, which leads to the abrupt use of wild resources of medicinally aromatic plants (MAPs). Cymbopogon citratus is a morphologically diverse MAP that is largely exploited in the food, cosmetics, and pharmaceutical industries. However, the intraspecific phytochemical and molecular diversity of C. citratus has yet to be explored.

Methodology

The germplasm was obtained from four different countries representing Pakistan, India, Bangladesh, and the United States. Oil extraction was performed by hydro distillation, and metabolic profiles of different accessions were generated by GC-MS. Seventeen functional molecular markers based on three genes encoding cytochrome P450, uridyl diphosphate glycosyltransferase and the 5S rRNA gene family were used to explore genetic diversity. Principal component analysis (PCA) and heatmaps were constructed using R software with the help of the gg-plot R package v1.0.5 for data validation.

Results

Among the 208 identified metabolites, citral was maximal, with a phytochemical contribution (1.92-27.73%), α-pinene (0.82-15.57%), verbenol (0.24-22.84%), neral (0.23-21.31%) and geranial acetate (0.43-15.65%). In the majority of accessions, citral was the dominant component. The highest concentration of citral was detected in 384541 (27.74%), 384527 (27.52%) belonging to Pakistan and one USA-based accession 38456 (27.71%). Region-specific grouping revealed a relationship between genetic diversity and geographical location. Pakistani accessions 384518, 38452, and 384544 genetically and 384535, 384518, and 384510 were phytochemically diverse.

Conclusion

The genetic diversity was more pronounced in cultivated accessions than in wild accessions. Moreover, it was observed that phytochemical diversity correlated with the altitude and temperature of the region.

Antifungal, Antioxidant and Antibiofilm Activities of Essential Oils of Cymbopogon spp

Essential oils (EOs) of Cymbopogon citratus and Cymbopogon proximus are known as sources of monoterpenes and sesquiterpenoids, although their biological activities have not been well investigated. In this study, the compositions of C. citratus and C. proximus EOs of Egyptian origin and their antifungal and antibiofilm properties against Candida spp. and Malassezia furfur were investigated. Antioxidant activities were also evaluated. GC-MS showed the presence of nine and eight constituents in C. citratus and C. proximus EOs, respectively, with geranial and neral as the major compounds of C. citratus EO and piperitone and α-terpinolene as the major compounds of C. proximus EO. Both EOs showed antifungal (MIC values ranging from 1.25 to 20 µL/ mL) and antibiofilm activities (% of reduction ranging from 27.65 ± 11.7 to 96.39 ± 2.8) against all yeast species. The antifungal and antibiofilm activities of C. citratus EO were significantly higher than those observed for C. proximus EO. M. furfur was more susceptible to both EOs than Candida spp. Both EOs exhibited the highest antioxidant activity. This study suggests that C. citratus and C. proximus EOs might be an excellent source of antifungal, antibiofilm and antioxidant drugs and might be useful for preventing Malassezia infections in both medical and veterinary medicine.

Review: Isoprenoid and aromatic cytokinins in shoot branching

Shoot branching is an important event of plant development that defines growth and reproduction. The BRANCHED1 gene (BRC1/TB1/FC1) is crucial for this process. Within the phytohormones, cytokinins directly activate axillary buds to promote shoot branching. In addition, strigolactones and auxins inhibit bud outgrowth. This review addresses the involvement of aromatic and isoprenoid cytokinins in shoot branching. And how auxins and strigolactones contribute to regulating this process also. The results obtained by others and our working group with lemongrass (Cymbopogon citratus) show that cytokinins affect both shoot and root apical meristem development, consistent with other plant species. However, many questions remain about how cytokinins and strigolactones antagonistically regulate BRC1 gene expression. Additionally, many details of the interaction among cytokinins, auxins, and strigolactones need to be clarified. We will gain a more comprehensive scheme of bud outgrowth with these details.

In silico Study Phytosterol Cymbopogon citratus and Curcuma longa as Inhibitor Agent 3C-Like Protease SARS-CoV-2

&lt;b&gt;Background and Objective:&lt;/b&gt; Lemongrass (&lt;i&gt;Cymbopogon citratus&lt;/i&gt;) and turmeric (&lt;i&gt;Curcuma longa&lt;/i&gt;) are widely used by the community for traditional medicinal spices and cooking spices. In the era of the COVID-19 pandemic, people use lemongrass and turmeric to increase immunity and protect the body from infection with the SARS-CoV-2 virus. However, the antiviral mechanisms have not been studied much. This study aims to predict the bioactivity of the phytosterol compounds of lemongrass and turmeric for COVID-19 therapy through inhibition of 3C-like protease (3CLPro) &lt;i&gt;in silico&lt;/i&gt;. &lt;b&gt;Materials and Methods:&lt;/b&gt; The 3CLPro protein 3D structure was downloaded from the PDB database with the access code 2ZU2 and the phytosterol compounds of lemongrass and turmeric were taken from PubChem. A total of 59 total phytosterol compounds from turmeric and lemongrass were screened for their bioactivity as an antiviral by using online PASS. Compounds with a high activating potential (Pa) were interacted with 3CLPro protein with the PyRx program and analyzed by Discovery Studio version 19.0 and LigPlus. &lt;b&gt;Results:&lt;/b&gt; A total of 22 total phytosterol compounds were identified as potential antiviral agents. Based on the Pa value, 15 phytosterol compounds have the potential to act as inhibitor agents for 3CLPro SARS-CoV-2. The phytosterol compounds of lemongrass and turmeric bind to the 3CLPro protein in the N-finger domain region and the A and B domain inhibitors connect residues of the 3CLPro protein. The phytosterols of lemongrass and turmeric show a low binding affinity with 3CLPro SARS-CoV-2, indicating a strong interaction between ligand and protein. The inhibition of phytosterols against 3CLPro protein can be used as a basis for determining candidates for COVID-19 therapeutic agents. &lt;b&gt;Conclusion:&lt;/b&gt; The phytosterol compounds contained in lemongrass and turmeric have the potential to act as 3CLPro inhibitors. Further studies both &lt;i&gt;in vitro&lt;/i&gt; and &lt;i&gt;in vivo&lt;/i&gt; need to be done to prove the inhibitory potential of phytosterol compounds.

Biochemical evaluation and molecular docking assessment of Cymbopogon citratus as a natural source of acetylcholine esterase (AChE)- targeting insecticides

Acetylcholinesterase (AChE) has been an effective target for insecticide development which is a very important aspect of the global fight against insect-borne diseases. The drastic reduction in the sensitivity of insects to AChE-targeting insecticides like organophosphates and carbamates have increased the need for insecticides of natural origin. In this study, we used Drosophila melanogaster as a model to investigate the insecticidal and AChE inhibitory potentials of Cymbopogon citratus and its bioactive compounds. Flies were exposed to 100 and 200 mg/mL C. citratus leaf extract for a 3-h survival assay followed by 45 min exposure for negative geotaxis and biochemical assays. Molecular docking analysis of 45 bioactive compounds of the plant was conducted against Drosophila melanogaster AChE (DmAChE). Exposure to C. citratus significantly reduced the survival rate of flies throughout the exposure period and this was accompanied by a significant decrease in percentage negative geotaxis, AChE activity, catalase activity, total thiol level and a significant increase in glutathione-S-transferase (GST) activity. The bioactive compounds of C. citratus showed varying levels of binding affinities for the enzyme. (+)-Cymbodiacetal scored highest (−9.407 kcal/mol) followed by proximadiol (−8.253 kcal/mol), geranylacetone (−8.177 kcal/mol), and rutin (−8.148 kcal/mol). The four compounds occupied the same binding pocket and interacted with important active site amino acid residues as the co-crystallized ligand (1qon). These compounds could be responsible for the insecticidal and AChE inhibitory potentials of C. citratus and they could be further explored in the development of AChE-targeting insecticides.

•

Cymbopogon citratus reduced the AChE activity, catalase activity, total thiol level in Drosophilia melanogaster.

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The bioactive compounds of Cymbopogon citratus displayed considerable binding affinities for Drosophila melanogaster AChE and the four top-scoring compounds are (+)-Cymbodiacetal, proximadiol, geranylacetone, and rutin.

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(+)-Cymbodiacetal showed the highest binding affinity to AChE (DmAChE).

Antitrypanosomal activity of hydromethanol extract of leaves of Cymbopogon citratus and seeds of Lepidium sativum: in-vivo mice model

Background

Trypanosomiasis is one of the neglected tropical diseases of both humans and animals which decreases their productivity and causes death in the worst scenario. Unavailability of vaccines, the low therapeutic index of trypanocidal drugs, and the development of resistance lead to the need for research focused on developing alternative treatment options especially from medicinal plants. The present study was aimed to investigate antitrypanosomal activities of leaves of Cymbopogon citratus and seeds of Lepidium sativum in in-vivo mice model.

Methods

The plant extracts were prepared by maceration using 80% methanol and reconstituted with 10% dimethyl sulfoxide (DMSO) to have the desired concentration. The test doses were adjusted to 100, 200 and 400 mg/kg based on the toxicity profile. The plants extracts were administered to the respective groups of mice after the 12^th day of field isolate T. congolense inoculation for seven consecutive days. The level of parasitemia, bodyweight, packed cell volume (PCV), and differential white blood cell counts were measured.

Results

The in -vivo test results revealed that both plant extracts had dose-dependent antitrypanosomal activity. Both crude extracts showed a significant reduction in parasite load (P < 0.05), increased or prevent the fall of PCV value (P < 0.05), decreased lymphocytosis and increased neutrophil counts (p < 0.05) and improved bodyweight but significant bodyweight increment (P < 0.05) was observed only in C. citratus treated mice compared to the negative and positive controls.

Conclusion

The present study concluded that the crude extracts of leaves of C. citratus and seeds of L. sativum had antitrypanosomal effects. Both plants extracts reduced parasitemia level, prevented anemia and improved bodyweight of treated mice. Comparative results from all tested parameters showed that the best activities were observed with C. citratus treated groups of mice.

Inhibition of α-glucosidase by flavonoids of Cymbopogon citratus (DC) Stapf

ETHNOPHARMACOLOGICAL RELEVANCE

Leaves extracts from Cymbopogon citratus (DC) Stapf. are widely used in traditional medicine exhibiting several in vivo biological activities, including antidiabetic. Several flavonoids, including aglycones and glycosides, were reported in this plant and previous studies suggested that flavonoids may interact with targets related to diabetes.

AIM OF THE STUDY

Evaluated the hypoglycemic activity of C. citratus flavonoids through α-glucosidase inhibition and assess the structure-activity relationship using molecular docking studies.

MATERIAL AND METHODS

An infusion of C. citratus leaves and its flavonoid-rich fraction were prepared. Five flavonoids from this fraction were isolated and structurally characterized by UV spectral analysis with shift reagents, HPLC-PDA-ESI/MSⁿ and ¹H NMR. The antidiabetic potential of C. citratus infusion, its flavonoid-rich fraction, glycosylated flavonoids and aglycones was evaluated trough the in vitro inhibition of yeast α-glucosidase. Posteriorly, molecular docking of the tested flavonoids was performed to investigate its possible interactions with the α-glucosidase pocket.

RESULTS

The infusion of C. citratus, its flavonoid-rich fraction, luteolin and five flavone glycosides namely, luteolin 6-C-β-glucopyranoside (isoorientin), luteolin 7-O-neohesperidoside (ionicerin), luteolin 7-O-β-glucopyranoside (cynaroside), Luteolin 2″-O-rhamnosyl-C-(6-deoxy-ribo-hexos-3-ulosyl) (cassiaoccidentalin B), luteolin 6-C-α-arabinofuranosil-(1→2)-α-L-rhamnopyranoside (kurilesin A) showed higher inhibitory activity than the reference drug. This activity increased by the addition of a sugar moiety. However, the di-glycosides were less active than mono-glycosides. The docking studies showed interactions of sugar moieties and A or B rings with the catalytic pocket mainly through hydrogen bonds.

CONCLUSIONS

Our results corroborate the potential of C. citratus as a medicinal plant for the treatment of diabetes and revealed that its flavonoid glycosides has hypoglycemic effect and can be explored as drug candidates to act as α-glucosidase inhibitors in the treatment of diabetes.

Pre-inoculation with arbuscular mycorrhizal fungi affects essential oil quality and the reproduction of root lesion nematode in Cymbopogon citratus

Cymbopogon citratus (lemongrass) is an important medicinal and aromatic plant containing citral-rich essential oil, of which the quality and quantity may be affected by nematode infection. Research has shown that arbuscular mycorrhizal fungi (AMF) may act as nematode biocontrol agents and improve the chemical composition of plants. Three experiments were conducted to assess the effects of AMF inoculation on vegetative growth, essential oil composition, induction of defense-related proteins, and control of Pratylenchus brachyurus in C. citratus. Seedlings were transplanted into pots inoculated with one of two AMF species (Rhizophagus clarus or Claroideoglomus etunicatum). At 30 days after AMF inoculation, plants were inoculated with P. brachyurus. Evaluations were performed at 75 days after nematode inoculation. Although both AMF treatments led to effective root colonization (> 84%), fungus inoculation was not effective in reducing P. brachyurus population density. Nevertheless, C. etunicatum promoted an increase in shoot weight, and AMF treatments contributed to preserving essential oil composition in nematode-infected plants. In addition, both AMF treatments enhanced polyphenol oxidase activity and R. clarus increased peroxidase activity after nematode inoculation.

and Cymbopogon citratus Stapf on the Main Insects of the Cotton Entomofauna in Côte d'Ivoire

Among the alternatives to environmentally toxic and socio-economically unacceptable chemical pesticides, essential oils from Ocimum gratissimum and Cymbopogon citratus were tested on the main pests and beneficial insects of the cotton plant in Côte d'Ivoire. After extraction and chemical analysis of the essential oils, field trials were carried out using a Fisher block system with three treatment repetitions where their effects compared with those of a registered synthetic insecticide (IBIS A 52 EC). Foliar applications of the products were carried out in accordance with the cotton plant protection extension programme in Côte d'Ivoire from the 45th to the 115th day after plant emergence, with one application every fortnight. Twenty-three and forty compounds representing about 96 and 99 % of the oil composition of O. gratissimum and C. citratus respectively were elucidated. The most abundant compounds were p-cymene and thymol (O. gratissimum) and myrcene, neral and geranial (C. citratus). The essential oil of O. gratissimum at concentrations of 2 and 5 % showed insecticidal activity on all pests (biting-sucking and carpophagous), except the phyllophagous Syllepte derogata. C. citratus, at a low concentration (1 %), was particularly toxic to whiteflies (Bemisia tabaci), however, it favoured the action of beneficial insects, specifically black ants and ladybirds in the cotton plots, unlike the chemical product. EO of O. gratissimum (1.60 and 4.62 mg GALAE/g, respectively) and C. citratus (2.26 and 2.78 mg GALAE, respectively) exhibited also significant acetyl and butyryl cholinesterase inhibitors. Insecticide formulations based on the essential oils of O. gratissimum and C. citratus offer favourable prospects for their use in cotton cultivation as an alternative to chemical pesticides.

Formulation Effects in the Antioxidant Activity of Extract from the Leaves of Cymbopogon citratus (DC) Stapf

Cymbopogon citratus DC (Stapf.) is a perennial grass and it is distributed around the world. It is used as a condiment for food and beverage flavouring in the form of infusions and decoctions of its dried leaves. Our previous studies have shown antioxidant, anti-inflammatory and gastroprotective activities for the infusion and its phenolic fractions. The aim of the present work was to develop oral dosage forms from a Cymbopogon citratus extract to be used as a functional food with antioxidant properties. Initially, an essential oil-free infusion was prepared, lyophilized and characterized by HPLC-PDA. Total phenols were quantified with the Folin-Ciocalteu method and the antioxidant activity was assessed by DPPH assay. Gelatine capsules containing the extract with different excipients, selected after DSC and IR trials, were prepared. A formulation exhibiting better antioxidant behaviour in a gastric environment was attained. These results suggest that the proposed formulation for this extract could be a valuable antioxidant product and, consequently, make an important contribution to "preventing" and minimizing diseases related to oxidative stress conditions.

Cymbopogon citratus (DC.) Stapf, citral and geraniol exhibit anticonvulsant and neuroprotective effects in pentylenetetrazole-induced seizures in zebrafish

ETHNOPHARMACOLOGICAL RELEVANCE

Cymbopogon citratus (DC.) Stapf (C. citratus) is consumed as an infusion in folk medicine due to its pharmacological properties and action in the central nervous system. Epilepsy is a neurological disorder that affects millions of people. Since the currently available antiepileptic drugs often cause undesirable side effects, new alternative therapeutic strategies based on medicinal plants have been proposed.

AIM OF THE STUDY

This study aimed to investigate the anticonvulsant and neuroprotective effects of C. citratus essential oil (EO) and hydroalcoholic extract (E1) from its leaves, as well as of its related compounds citral (CIT) and geraniol (GER) against the effects of pentylenetetrazole (PTZ) induced seizures in zebrafish (Danio rerio).

MATERIALS AND METHODS

To evaluate the anticonvulsant properties of the samples, adult animals were pre-treated (by immersion) and subsequently exposed to PTZ solution. The involvement of GABA_A receptors in the antiepileptic effects was investigated by the coadministration of flumazenil (FMZ), a known GABA_A receptor antagonist. Oxidative stress markers malondialdehyde (MDA), glutathione (GSH), catalase (CAT) and nitric oxide (NO) were assessed in zebrafish brain homogenates after PTZ exposure.

RESULTS

All samples increased the latency time for the first seizure, which was reduced when animals were pretreated with FMZ, suggesting the involvement of GABA_A receptors in the observed properties. The association between CIT and GER at the lowest concentration studied showed a synergistic effect on the anticonvulsant activity. Decreases in MDA and NO levels and increases in GSH and CAT levels in the brain of treated animals suggested the neuroprotective effect of the compounds investigated.

CONCLUSIONS

Our results proved that C. citratus EO, E1, CIT and GER have anticonvulsant effects in zebrafish and could be used as a promising adjuvant therapeutic strategy for epilepsy treatment. Furthermore, zebrafish demonstrated to be an alternative animal model of epilepsy to evaluate the anticonvulsant and neuroprotective effects of C. citratus.

Evaluation of Seven Essential Oils as Seed Treatments against Seedborne Fungal Pathogens of Cucurbita maxima

Essential oils are gaining interest as environmentally friendly alternatives to synthetic fungicides for management of seedborne pathogens. Here, seven essential oils were initially tested in vivo for disinfection of squash seeds (Cucurbita maxima) naturally contaminated by Stagonosporopsis cucurbitacearum, Alternaria alternata, Fusarium fujikuro, Fusarium solani, Paramyrothecium roridum, Albifimbria verrucaria, Curvularia spicifera, and Rhizopus stolonifer. The seeds were treated with essential oils from Cymbopogon citratus, Lavandula dentata, Lavandula hybrida, Melaleuca alternifolia, Laurus nobilis, and Origanum majorana (#1 and #2). Incidence of S. cucurbitacearum was reduced, representing a range between 67.0% in L. nobilis to 84.4% in O. majorana #2. Treatments at 0.5 mg/mL essential oils did not affect seed germination, although radicles were shorter than controls, except with C. citratus and O. majorana #1 essential oils. Four days after seeding, seedling emergence was 20%, 30%, and 10% for control seeds and seeds treated with C. citratus essential oil (0.5 mg/mL) and fungicides (25 g/L difenoconazole plus 25 g/L fludioxonil). S. cucurbitacearum incidence was reduced by ~40% for plantlets from seeds treated with C. citratus essential oil. These data show the effectiveness of this essential oil to control the transmission of S. cucurbitacearum from seeds to plantlets, and thus define their potential use for seed decontamination in integrated pest management and organic agriculture.

Identification of PTP1B regulators from Cymbopogon citratus and its enrichment analysis for diabetes mellitus

PTP1B is identified as the insulin signaling pathway downregulator; involved in pancreatic β-cell apoptosis. Further, it associates in regulating multiple pathways in diabetes mellitus; kindled us to identify the binding affinity of bioactives from Cymbopogon citratus by targeting PTP1B and identify the probably associated with it; further identifying the probable pathways involved in diabetes mellitus. In this regard, ChEBI database was used to retrieve bio-actives from C. citrates and 3D structures for the same were obtained from the PubChem database. The energy of bioactives was minimized and converted into ligand and the docking was carried using autodock 4.0 against PTP1B. Further, multiple characters of bio-actives like drug-likeness score, ADMET profile, probable adverse effects, and boiled egg model for bioavailability were also studied. Swertiajaponin was predicted for the highest drug-likeness score i.e. 0.26. However, swertiajaponin was predicted with the highest probable side effect of nephrotoxicity with pharmacological activity of 0.478. Similarly, swertiajaponin was predicted for the highest binding affinity with PTP1B with the binding energy of - 8.3 kcal/mol. Likewise, KEGG identified 80 pathways associated with PTP1B modulation in which 7 pathways were involved in diabetes mellitus in which FoxO signaling pathway was predicted to have the least false discovery rate by modulating 7 genes. Swertiajaponin could act as the potent inhibitor of PTP1B; scored highest druglikeness score but possessed minimum GIT absorptivity; further, PTP1B was identified to be linked with multiple pathways that are concerned with diabetes mellitus.

Optimization of extraction conditions of phenolic compounds from Cymbopogon citratus and evaluation of phenolics and aroma profiles of extract

Decoction extraction procedure was implemented to regain phenolic compounds from C. citratus leaves. The extraction variables, solid/liquid ratio (2–5 g/100 mL), temperature (85–95 °C), and time (5–10 min) were assessed by central composite design for process optimization. Antioxidant activity (DPPH) and total polyphenol content (TPC) were monitored as responses. The TPC and DPPH were 71.98 ± 0.33 mg GAE/100 mL extract and 80.63 ± 0.49 mg TE/100mL extract respectively under optimal conditions (solid/liquid ratio = 5, temperature = 93.8 °C and time 11.3 min). The evaluation of phenolic compounds and volatile compounds of C. citratus extract at conditions for optimum extraction revealed that caffeic (20.81 ± 0.003 mg/100mL) and syringic acids (18.63 ± 7.390 mg/100mL) were the main phenolic compounds while citral and geraniol were the primary volatile compounds. The results achieved herein suits the potential use of C. citratus extract as natural source of antioxidant and aroma compounds that can be employed in different industrial sectors.

Practical application

Lemongrass obtained at the optimal extraction conditions is a good source of antioxidants and the extract has organic acids and a lemon scent due to the presence of citral. This extract can thereby be incorporated in the production of beverages which can help aromatize the beverage and also contribute in the addition of the antioxidant property of the beverage. It is also rich in organic acids, the main being propionic acid, which is known to have antimicrobial activity primarily against bacteria and mold. The lemongrass extract can therefore, extend the shelf life of the beverage they are incorporated in and also the citral present in lemongrass has antimicrobial properties.

Antifungal Activity and Chemical Composition of Seven Essential Oils to Control the Main Seedborne Fungi of Cucurbits

Essential oils represent novel alternatives to application of synthetic fungicides to control against seedborne pathogens. This study investigated seven essential oils for in vitro growth inhibition of the main seedborne pathogens of cucurbits. Cymbopogon citratus essential oil completely inhibited mycelial growth of Stagonosporopsis cucurbitacearum and Alternaria alternata at 0.6 and 0.9 mg/mL, respectively. At 1 mg/mL, Lavandula dentata, Lavandula hybrida, Melaleuca alternifolia, Laurus nobilis, and two Origanum majorana essential oils inhibited mycelia growth of A. alternata by 54%, 71%, 68%, 36%, 90%, and 74%, respectively. S. cucurbitacearum mycelia growth was more sensitive to Lavandula essential oils, with inhibition of ~74% at 1 mg/mL. To determine the main compounds in these essential oils that might be responsible for this antifungal activity, they were analyzed by gas chromatography–mass spectrometry (GC-MS). C. citratus essential oil showed cirtal as its main constituent, while L. dentata and L. nobilis essential oils showed eucalyptol. The M. alternifolia and two O. majorana essential oils had terpinen-4-ol as the major constituent, while for L. hybrida essential oil, this was linalool. Thus, in vitro, these essential oils can inhibit the main seedborne fungi of cucurbits, with future in vivo studies now needed to confirm these activities.

Lemongrass (Cymbopogon citratus (D.C.) Stapf) Presents Antitumoral Effect and Improve Chemotherapy Activity in Prostate Cancer Cells

BACKGROUND

Prostate cancer is the most common visceral neoplasia in men and frequently present chemotherapy resistance. In this context, lemongrass (Cymbopogon citratus (D.C.) Stapf) has been studied, since it presents many important biological activities, such as anticancer.

OBJECTIVE

We investigated the antitumor effect of lemongrass and in chemotherapy activity using prostate cancer cells line (DU-145).

METHODS

DU-145 cells were exposed to different concentrations of aqueous extract of lemongrass (30; 100; 300; 500 and 1000 μg/mL), isolated and in combination with docetaxel, during 24 and 72 hours. After, cell viability and proliferation, oxidative metabolism, colony formation and cell cycle analyses were performed. Also, we exposed African green monkey kidney cell line (VERO) to the same lemongrass concentrations to investigate a possible toxicity of this extract.

RESULTS

Our findings suggested that lemongrass presented an antitumor effect and improved docetaxel chemotherapy activity by decreasing cell viability and proliferation as well as colony formation. Moreover, we found an oxidative stress increased and cell cycle arresting in G0/G1 phase. In addition, this extract presented selectivity action for cancer cells, since it did not cause cytotoxicity in normal cells, ensuring non-toxic therapeutic concentrations.

CONCLUSION

Lemongrass is a promising medicinal plant that could be used during chemotherapeutic treatment, in order to potentiate the antitumor response and decrease the resistance of prostate cancer.

Effect of Cymbopogon citratus Essential Oil (EO) on Handling Stress in Giant Freshwater Prawn (Macrobrachium rosenbergii)

BACKGROUND AND OBJECTIVE

Effects of Cymbopogon citratus essential oil (EO) was tested on minimizing handling stress in Macrobrachium rosenbergii through the evaluation of their metabolite responses [glucose, lactate, glycogen, protein, Lactate Dehydrogenase (LDH), Malate Dehydrogenase (MDH), Acetylcholinesterase (AChE) and Alanine Aminotransferase (ALT)]. This study aimed to investigate the efficacy of C. citratus extract in the anaesthetization of M. rosenbergii.

MATERIALS AND METHODS

Three treatments including control, prawn exposed to stress alone (T1) and prawn exposed to stress in the presence of C. citratus EO (T2) were tested. A C. citratus EO at 500 μL L-1 had been determined in a previous study and was selected as the critical dose to be applied as an anesthetic agent. Handling stress was induced into prawns by netting, at 2 min interval for 30 min and their hemolymph were collected to determine the metabolite responses.

RESULTS

The increase of glucose, lactate and LDH of M. rosenbergii when exposed to handling stress alone (T1) in comparison to T2 (stress with anesthetic C. citratus EO) were identified. Further, a low glycogen level in parallel with low AChE activity was observed which indicates the involvement of secondary metabolites to cope with the energy demand in T1 over T2.

CONCLUSION

This study indicates the efficiency of C. citratus EO to reduce stress during handling in M. rosenbergii.

Effects of Three Herbs on Methane Emissions from Beef Cattle

Simple Summary

Cattle represent a significant source of greenhouse gases (GHGs). In 2010, cattle emitted 5.0 gigatons of CO₂ equivalents globally, which represents about 62% of the livestock sector emissions. Therefore, mitigating GHGs such as methane (CH₄) originating from the cattle industry, offers an opportunity to reduce GHG emissions and climate change over the short term. Ruminant nutritionists have developed different strategies, which include the use of antibiotics, herbs and chemical compounds, such as nitrate, to manipulate rumen fermentation and reduce CH₄ emissions. So, the objectives of the present work were to evaluate the in vivo antimethanogenic effects of three herbs: Cymbopogon citratus (CC), Matricaria chamomilla (MC) and Cosmos bipinnatus (CB) on beef cattle fed a high in concentrate diet and the effects of increasing levels of CC on enteric CH₄ emissions by beef cattle fed a ration low in concentrate. We concluded that CC significantly reduced methane yield (g of CH₄/kg of DMI) by 33%, CB reduced methane yield by 28%, and MC had no significant effect. In Experiment 2, CC supplemented with 2% of the daily DMI significantly reduced the total daily CH₄ emissions by 26% without affecting the supply of nutrients to the animal.

Abstract

The objectives of the present work were to evaluate the in vivo antimethanogenic effects of Cymbopogon citratus (CC), Matricaria chamomilla (MC) and Cosmos bipinnatus (CB) on beef cattle fed a high in concentrate diet (forage-to-concentrate ratio [F:C] of 19.4:80.6), and the effects of increasing levels of CC (0%, 2%, 3%, and 4% of the daily DM intake (DMI)) on enteric CH₄ emissions by beef cattle fed a ration low in concentrate (F:C ratio of 49.3:50.7). Two experiments were conducted to address the objectives. For the first experiment, eight Charolais × Brown Swiss steers distributed in a replicated 4 × 4 Latin square experimental design were used. Four treatments were evaluated: (1) control diet (CO), (2) CO + 365 g dry matter (DM)/d CB, (3) CO + 365 g DM/d MC, (4) CO + 100 g DM/d CC. For Experiment 2, four Charolais x Brown Swiss steers distributed in a single 4 × 4 Latin square design were used. It was concluded that 100 g DM per day CC and 365 g DM per day CB (Experiment 1) reduced CH₄ yield of beef cattle. In Experiment 2, CC supplementation levels exceeding 2% of DMI reduced daily CH₄ emissions but at the expense of decreasing digestibility of DM.

UPLC-Orbitrap HRMS metabolic profiling of Cymbopogon citratus cultivated in Egypt; neuroprotective effect against AlCl3-induced neurotoxicity in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cymbopogon citratus (lemongrass) is commonly used in teas, soups and treat inflammatory-based ailments, vascular and nervous disorders.

AIM OF THE STUDY

The study aimed to evaluate the neuroprotective effect of Cymbopogon citratus leaves through scientific protocol. The effect of aqueous (AE) and ethanolic (EE) extracts was evaluated against AlCl₃-induced Alzheimer's disease (AD) in rats. Metabolic profiling of the plant, isolation of bioactive compounds and standardization of the active fraction were investigated.

MATERIALS AND METHODS

AE of Cymbopogon citratus leaves was prepared as per traditional method (infusion), EE was prepared by repeated maceration in 90% ethanol, bioactive fraction (BAEE) was obtained from EE and the active compounds thereof were obtained by column chromatography. Metabolic profiling of Cymbopogon citratus was performed by UPLC-Orbitrap HRMS and HPLC was used for standardization. AlCl₃-induced Alzheimer's rats were used to assess neuroprotective effect of the extracts. Neuroprotective mechanism(s) of Cymbopogon citratus extracts was clarified through histopathological examination of brain tissues, estimation of AD biochemical markers, oxidative stress and neuroinflammation in brain homogenates. In addition, antioxidant (using DPPH assay) and anticholinesterase (using modified Ellman's method) activities were investigated.

RESULTS

AlCl₃-treated rats (17 mg/kg/day) showed histopathological alteration in brain tissues together with elevated levels of Aβ, tau proteins, MDA, NF-kB and IL-6. However, treatment with AE and EE of Cymbopogon citratus leaves prevented the pathological changes and maintained the levels of oxidative stress and inflammatory markers. In addition, BAEE significantly inhibited acetylcholinesterase enzyme (2.11 ± 0.11 mg/ml) and exhibited a strong antioxidant activity (24.99 ± 0.00 μg/ml). UPLC-MS of Cymbopogon citratus leaves showed peaks for twenty-eight compounds, twenty-one of them were identified. Three flavonoids; isoorientin, isoschaftoside and luteolin-7-O-neohesperidoside were isolated from BAEE as major constituents. The powdered leaves of Cymbopogon citratus was found to contain remarkable amounts of caffeic acid (3.49 mg/g dry wt.) and isoorientin (7.37 mg/g dry wt.) as determined by HPLC.

CONCLUSION

Cymbopogon citratus ethanolic extract attenuates AlCl₃-induced neurotoxicity in rats through inhibition of oxidative stress and inflammatory markers. This effect could possibly attributed, in part to its high content of phenolic acids and flavonoids. Accordingly, we recommend Cymbopogon citratus leaves for protection against AD.

in human arteries

ETHNOPHARMACOLOGICAL RELEVANCE

Cymbopogon citratus (DC.) Stapf has been traditionally used mainly for inflammatory diseases and hypertension. However, the mechanisms underlying its vascular activity remain to be fully characterized and the fractions responsible for its cardiovascular activity are still unknown.

AIM OF THE STUDY

In this study, we aimed to assess the vascular activity of Cymbopogon citratus in human arteries and to study the role of cyclooxygenase in its vasorelaxant effects.

MATERIALS AND METHODS

Vascular effects of leaves infusion and three fractions (phenolic acids, flavonoids and tannins) were studied using distal segments of human internal thoracic arteries harvested from patients undergoing coronary revascularization, which were mounted as rings in tissue organ baths and maintained at 37 °C in Krebs Henseleit buffer. The effect on basal vascular tone, the effect on the noradrenaline-induced contraction and the vasorelaxant effects were assessed. The role of cyclooxygenase was evaluated with indomethacin.

RESULTS

Our results showed a mild effect on the basal vessel tone of the infusion. A significant inhibition on the adrenergic-mediated vasoconstriction was observed for the infusion (0.0002 mg/mL) and the flavonoid fraction (0.2 mg/mL), despite a potentiation was observed in some conditions. A vasorelaxant effect was observed for both the infusion (6.46% of maximal relaxation) and the tannin fraction (26.91% of maximal relaxation, P < 0.05 vs. infusion). Incubation with indomethacin (10 μM) elicited a decrease in the vasorelaxation to the infusion (P < 0.05).

CONCLUSIONS

These results suggest that cyclooxygenase may be involved in the vasorelaxation to the infusion of Cymbopogon citratus and that tannins are the compound fraction mainly responsible for this vasorelaxation.

nematodes from sheep

Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 μg mL-1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.

The Essential Oil of Cymbopogon citratus Stapt and Carvacrol: An Approach of the Antitumor Effect on 7,12-Dimethylbenz-[α]-anthracene (DMBA)-Induced Breast Cancer in Female Rats

C. citratus essential oil and carvacrol have shown an antitumor effect on breast tumor cell lines; the main objective of this research was to evaluate the antitumor effect of the essential oil of Cymbopogon citratus (EOCc) and carvacrol on 7,12-dimethylbenz [a] anthracene (DMBA)-induced breast cancer in female rats. Cancer was induced by a single administration of DMBA at dose of 80 mg/kg body weight (BW). A total of 54 female Holtzman rats were randomly assigned into 9 groups (n = 6). Group I: PS (Physiological saline); Group II: DMBA; Groups III, IV, and V: DMBA + EOCc at doses of 50, 100 and 200 mg/kg/day BW, respectively; Groups VI, VII, and VIII: DMBA + carvacrol at doses of 50, 100 and 200 mg/kg/day BW, respectively; and group IX: DMBA + EOCc + carvacrol at doses of 100 mg/kg/day BW. The treatment lasted 14 weeks. As results, EOCc showed a reduction in tumors as well as necrosis and mitosis. Animals treated with carvacrol did not show necrosis, mitosis, or infiltration. Carvacrol at dose of 100 mg/kg/day BW revealed a significant decrease in the cumulative tumor volume down to 0.11 ± 0.05 cm3 compared to 0.38 ± 0.04 cm3 of the DMBA group (p < 0.01). It is concluded that EOCc and carvacrol had an antitumor effect on DMBA-induced breast cancer in female rats.

In vitro acaricidal activity of Cymbopogon citratus, Cymbopogon nardus and Mentha arvensis against Rhipicephalus microplus (Acari: Ixodidae)

The chemical composition and acaricidal activity of plant-derived essential oils was assessed against Rhipicephalus microplus ticks. The essential oils of Mentha arvensis, Cymbopogon citratus and C. nardus were assessed for acaricidal activity against Rhipicephalus microplus. Essential oils (EO) of plants were separated by hydrodistillation (three times) and analyzed using gas chromatography - mass spectrometer (GC-MS). For bioassays, engorged females of R. microplus were exposed to C. citratus and C. nardus EO at 2%, 3%, 4% and 5% concentrations; and to M. arvensis EO at 1%, 3%, and 5% for 5 min. The weight egg mass, nutrient index (N.I), egg production index (E.P.I), hatching and control rate were evaluated. Non-feed larvae of R. microplus were exposed to essential oils with 0.25%, 0.5%; 1%; 1.5% and 2% concentrations; the mortality rate was measured after 48 h. Only engorged females presented reduced biological activities (oviposition, E.P.I) after exposure to M. arvensis at 3%, when in comparison to both positive and negative controls. The hatchability of R. microplus larvae ranged from 66.9% (after exposure to C. nardus EO at 5%) to 99.2% (positive control). The nutrition index was lower (46.6%) for the exposure to M. arvensis EO at 5%. M. arvensis at 3% and 5% concentrations was significantly efficient for engorged females when compared to control (53.7% and 47.5%, respectively). C. citratus EO at 1%, 1.5% and 2% concentrations yielded better results in the larval packet test, causing 100% mortality. Nonetheless, C. nardus and M. arvensis EO at 2% yielded 66% and 39% mortality, respectively. The study showed that M. arvensis presented potential for the control of R. microplus engorged females while C. citratus and C. nardus presented potential as a larvicide.

Adulticidal activities of Cymbopogon citratus (Stapf.) and Eucalyptus globulus (Labill.) essential oils and of their synergistic combinations against Aedes aegypti (L.), Aedes albopictus (Skuse), and Musca domestica (L.)

The knockdown and adulticidal activities of individual Cymbopogon citratus and Eucalyptus globulus essential oils (EOs) and their combinations were evaluated against three medical insect pests (Aedes aegypti, Aedes albopictus, and Musca domestica) using a WHO susceptibility test. The knockdown and adulticidal activities against the three medical insect pests of combinations of C. citratus and E. globulus EOs were higher than those of individual EOs alone. Combinations of 7.5% C. citratus + 7.5% E. globulus EOs and 10% C. citratus + 10% E. globulus EOs exhibited the highest efficacy against females of the three species with 100% knockdown and mortality rates at 1 and 24 h after exposure, respectively. Their adulticidal activities were equivalent to that of 10% w/v cypermethrin. In contrast, 70% v/v ethyl alcohol negative control was not effective at all. The combinations of EOs showed a synergistic effect, i.e., their adulticidal activity was improved by 0.2 to 100%, with increased knockdown and mortality rates, compared to individual EOs. The highest synergistic effect on effective knockdown and adulticidal activities against females of the three species was achieved by a combination of 2.5% C. citratus + 2.5% E. globulus EOs, with 36.6 to 100% knockdown rate increase and 33.5 to 98.9% mortality rate increase. This study demonstrates that all tested combinations of C. citratus and E. globulus EOs were effective adulticidal agents against females of Ae. aegypti, Ae. albopictus, and M. domestica and have a high potential for development into a botanical insecticide for controlling populations of Aedes mosquitoes and houseflies.

Phytochemical characterization and antimicrobial activity of Cymbopogon citratus extract for application as natural antioxidant in fresh sausage

The development of natural additives is considered an important research topic. In this work, the use of Cymbopogon citratus (CC) extract as a natural additive for chicken sausage refrigerated was investigated. The CC extract was characterized by electrospray ionization with high-resolution time-of-flight mass spectrometry (ESI-ToF-MS) and the identified compounds were directly related to the antioxidant activity demonstrated by CC in the fresh sausage. In total, 31 phytochemical compounds were identified, and 27 of these still were not described in the literature for CC. The antimicrobial activity showed that CC extract is a potential antibacterial agent. Besides, the results showed that CC extract reduced lipid oxidation compared to synthetic additive. The sensorial characteristics were maintained, demonstrating good acceptability by the consumer. The results confirmed that CC can keep the quality of chicken sausage refrigerated for up to 42 days of storage.

The Effect of Nanocoatings Enriched with Essential Oils on 'Rocha' Pear Long Storage

The effect of coating 'Rocha' pears with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) or citral (Cit) was investigated. Fruit were treated with the nanoemulsions: sodium alginate 2% (w/w) + citral 1% (w/w) (Cit1%); sodium alginate 2% (w/w) + citral 2% (w/w) (Cit2%); sodium alginate 2% (w/w) + lemongrass 1.25% (w/w) (LG1.25%); sodium alginate 2% (w/w) + lemongrass 2.5% (w/w) (LG2.5%). Then, fruit were stored at 0 °C and at 95% relative humidity, for six months. Fruit samples were taken after two, four and six months, and then placed at 22 °C. Upon removal and after 7 d shelf-life, fruit were evaluated for colour CIE (L*, h◦), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage, microbial growth, symptoms of superficial scald and internal browning. All nanoemulsions had droplets in the nano range <500 nm, showed uniformity of particle size and stable dispersion. Cit-nanoemulsions had lower droplet size and higher stability than LG. No nanoemulsion showed cytotoxicity. Coatings reduced fruit colour evolution and preserved better firmness than control. After shelf-life, better firmness was found in LG-coated fruit. Coatings did not affect SSC and TA. Microbial growth was below the safety limits in all treatments. Fruit treated with LG-nanoemulsions did not show scald symptoms and panelists preferred LG1.25% coated fruit. Cit2% treated fruit showed the highest scald and internal browning symptoms, while LG1.25% did not show any disorders. This study suggests that LG-nanocoatings have the potential for preserving the quality of 'Rocha' pear.

Cymbopogon Citratus Functionalized Green Synthesis of CuO-Nanoparticles: Novel Prospects as Antibacterial and Antibiofilm Agents

Chemically synthesized copper oxide nanoparticles (CuONPs) involve the generation of toxic products, which narrowed its biological application. Hence, we have developed a one-pot, green method for CuONP production employing the leaf extract of Cymbopogon citratus (CLE). Gas chromatography-mass spectrometry (GC-MS) analysis confirmed the capping of CuONPs by CLE esters (CLE-CuONPs). Fourier-transform infrared (FTIR) showed phenolics, sugars, and proteins mediated nucleation and stability of CLE-CuONPs. X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed CLE-CuONPs between 11.4 to 14.5 nm. Staphylococcus aureus-1 (MRSA-1), Staphylococcus aureus-2 (MSSA-2) exposed to CLE-CuONPs (1500 µg/mL) showed 51.4%, 32.41% survival, while Escherichia coli-336 (E. coli-336) exposed to 1000 µg/mL CLE-CuONPs showed 45.27% survival. Scanning electron microscopy (SEM) of CLE-CuONPs treated E. coli-336, MSSA-2 and MRSA-1 showed morphological deformations. The biofilm production by E. coli-336 and MRSA-1 also declined to 33.0 ± 3.2% and 49.0 ± 3.1% at 2000 µg/mL of CLE-CuONPs. Atomic absorption spectroscopy (AAS) showed 22.80 ± 2.6%, 19.2 ± 4.2%, and 16.2 ± 3.6% accumulation of Cu2+ in E. coli-336, MSSA-2, and MRSA-1. Overall, the data exhibited excellent antibacterial and antibiofilm efficacies of esters functionalized CLE-CuONPs, indicating its putative application as a novel nano-antibiotic against multi drug resistance (MDR) pathogenic clinical isolates.

Phytochemical analysis and evaluation of skin irritation, acute and sub-acute toxicity of Cymbopogon citratus essential oil in mice and rabbits

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C. citrates essential oil contains about 71.297 % citral.

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10 % ointment formulation of C. citratus oils did not cause skin irritation.

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Oral LD₅₀ of C. citratus essential oil was greater than 2000 mg/kg.

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C. citratus essential oil didn’t produce any toxicity sign.

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No histopathological changes were detected in the organs tested.

Cymbopogon citratus has been used by the local people in Ankober district, northern Ethiopia, as traditional medicine to treat various ailments. Its essential oil has been shown to have antibacterial, antifungal, antiprotozoal, anti-carcinogenic, anti-inflammatory and antioxidant activities amongst others. This study was conducted to determine skin irritation, acute and subacute toxicity of C. citratus essential oil in mice and rabbits. The essential oil was analyzed using GC–MS. The essential oil at dose of 2000 mg/kg body weight was administered to mice for 21 consecutive days. The mice mortality, behavioral change, injury and other signs of illness were recorded once daily. Biochemical parameters were evaluated. Liver and kidney were taken after sacrifice for gross findings and histological analyses. 10 % ointment formulation of C. citratus oils was applied on the rabbit skin to determine skin irritation effects. The result revealed, the presence of citral (71.297%), myrcene (19.034%), 4, 5-epoxycarene (2.780%), linalool (1.713%), ((S)-cis-verbenol (1.110 %), linalool (1.713 %), ((S)-cis-verbenol (1.110 %) and undecan-2-one (1.001 %) in the C. citratus essential oil. There was no significant difference (p > 0.05) in the body weights, gross abnormalities of the organs and biochemical parameters compared to the control. No histopathological changes were detected in the organs tested. 10 % ointment formulation of C. citratus oils did not cause skin irritation. Analysis of results leads to the conclusion that Ethiopian C. citratus essential oil may be considered as relatively safe and non-toxic.