Solvent effects on phytochemical constituent profiles and antioxidant activities, using four different extraction formulations for analysis of Bucida buceras L. and Phoradendron californicum

In vitro study of the antioxidant, antiproliferative, and anthelmintic properties of some medicinal plants of Kokrajhar district, India

Alstonia scholaris, Cardiospermum halicacabum, Hydrocotyle sibthorpioides, and Hypericum japonicum are important folk medicinal plants used by tribal communities of Bodoland region of Assam to treat helminth infections. Because of their ethnomedicinal values, the present study was designed to investigate the antioxidant, antiproliferative, and anthelmintic activities of the plants. The antioxidant activity was measured by total antioxidant capacity, total phenolics (TPC), total flavonoid (TFC), FRAP, DPPH, ABTS, and TBARS assay. Antiproliferative and apoptosis-inducing activities of plants were conducted in Dalton's lymphoma (DL) cells. Cells were treated for 24 h with different doses (25-200 mg/mL) of plant extracts. Anthelmintic study was conducted by treating the Paramphistomum sp. at different doses of plant extracts. Phytochemical and antioxidant studies showed rich TPC, TFC, and free radical scavenging activity in H. japonicum and H. sibthorpioides. Both the antiproliferative and anthelmintic bioassays showed a dose-dependent efficacy in all plants. H. japonicum showed the strongest anthelmintic activity (LC₅₀ 0.21 mg/mL) followed by H. sibthorpioides (5.36 mg/mL), C. halicacabum (13.40 mg/mL), and A. scholaris (18.40 mg/mL). Evidently, H. sibthorpioides showed the strongest antiproliferative and apoptosis-inducing activities among all the plants. The study observed a positive correlation between the antioxidant properties and antiproliferative and anthelmintic activities of the plants. We, therefore, conclude that the phytocompounds present in the crude extracts along with antioxidant molecules may have combined effects contributing to the antiproliferative and anthelmintic activities of the plants.

Exploring the Chemical Profiles and Biological Values of Two Spondias Species (S. dulcis and S. mombin): Valuable Sources of Bioactive Natural Products

Spondias species have been used in traditional medicine for different human ailments. In this study, the effect of different solvents (ethyl acetate, methanol, and water) and extraction methods (infusion, maceration, and Soxhlet extraction) on the enzyme inhibitory activity against acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, α-glucosidase, and antioxidant properties of S. mombin and S. dulcis leaves and stem bark were evaluated. Ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) yield in the identification and/or annotation of 98 compounds showing that the main secondary metabolites of the plant are gallic and ellagic acids and their derivatives, ellagitannins, hydroxybenzoic, hydroxycinnamic, acylquinic acids and flavonols, flavanones, and flavanonols. The leaves infusion of both Spondias species showed highest inhibition against acetylcholinesterase (AChE) (10.10 and 10.45 mg galantamine equivalent (GALAE)/g, for S. dulcis and S. mombin, respectively). The ethyl acetate extracts of the stem bark of S. mombin and S. dulcis actively inhibited α-glucosidase. Methanolic extracts of the leaves and stem bark exhibited highest tyrosinase inhibitory action. Antioxidant activity and higher levels of phenolics were observed for the methanolic extracts of Spondias. The results suggested that the Spondias species could be considered as natural phyto-therapeutic agents in medicinal and cosmeceutical applications.

LC-MS/MS characterization, antidiabetic, antioxidative, and antibacterial effects of different solvent extracts of Anamur banana (Musa Cavendishii)

The main objective of this study was to examine the phenolic compounds and the antibacterial, antioxidant, anti-α-glucosidase and anti-α-amylase activities of the different extracts (methanol, ethanol and hexane) of Musa cavendishii collected from the Anamur district in Turkey. LC-MS/MS was used to identify phenolic compounds. Quinic acid, acotinic acid, hesperidin and amentoflavone were identified in methanol extract. These phenolic compounds, excluding hesperidin, were also identified in the ethanol extract. Methanolic extract appeared the most active in all enzyme inhibition, antibacterial and antioxidative activity assays which is mainly due to its rich phenolic content. The methanol extract of banana showed the highest anti-α-glucosidase and anti-α-amylase activities with IC50 values of 5.45 ± 0.39 mg/mL, 9.70 ± 0.29 mg/mL, respectively. This study showed that methanol and ethanol extract, especially the methanol extract, have potential for use in the development of functional foods for reducing the diabetes and bacterial risks.

The Effects of Tormentic Acid and Extracts from Callistemon citrinus on Candida albicans and Candida tropicalis Growth and Inhibition of Ergosterol Biosynthesis in Candida albicans

Candida albicans and Candida tropicalis are the leading causes of human fungal infections worldwide. There is an increase in resistance of Candida pathogens to existing antifungal drugs leading to a need to find new sources of antifungal agents. Tormentic acid has been isolated from different plants including Callistemon citrinus and has been found to possess antimicrobial properties, including antifungal activity. The study aimed to determine the effects of tormentic and extracts from C. citrinus on C. albicans and C. tropicalis and a possible mode of action. The extracts and tormentic acid were screened for antifungal activity using the broth microdilution method. The growth of both species was inhibited by the extracts, and C. albicans was more susceptible to the extract compared to C. tropicalis. The growth of C. albicans was inhibited by 80% at 100 μg/ml of both the DCM: methanol extract and the ethanol: water extract. Tormentic acid reduced the growth of C. albicans by 72% at 100 μg/ml. The effects of the extracts and tormentic acid on ergosterol content in C. albicans were determined using a UV/Vis scanning spectrophotometer. At concentrations of tormentic acid of 25 μg/ml, 50 μg/ml, 100 μg/ml, and 200 μg/ml, the content of ergosterol was decreased by 22%, 36%, 48%, and 78%, respectively. Similarly, the DCM: methanol extract at 100 μg/ml and 200 μg/ml decreased the content by 78% and 88%, respectively. A dose-dependent decrease in ergosterol content was observed in cells exposed to miconazole with a 25 μg/ml concentration causing a 100% decrease in ergosterol content. Therefore, tormentic acid inhibits the synthesis of ergosterol in C. albicans. Modifications of the structure of tormentic acid to increase its antifungal potency may be explored in further studies.

Ultrasound-homogenization-assisted extraction of polyphenols from coconut mesocarp: Optimization study

Coconut pericarp (shell fiber (mesocarp) and shell (endocarp)), the main by-product of coconut production, is often discarded and causing serious environmental pollution. To make better use of coconut pericarp, the extraction process of polyphenols from coconut mesocarp (CM) carefully studied by screening seven solvent systems, optimizing the assisted ultrasonic process by response surface methodology, and comparing the four processes of Ultrasound-Assisted Extraction (UAE), Homogenization-Assisted Extraction (HAE), Homogenization-Ultrasound-Assisted Extraction (HUAE), and Ultrasound-Homogenization-Assisted Extraction (UHAE). The UAE and HAE are considered to be the main methods for efficient extraction of natural active ingredients. The former effectively destroys the cell wall structure and promotes the intermolecular diffusion based on the cavitation, thermal and mechanical effect of ultrasonic, while the latter breaks the material based on strong shear force between the rotor and stator. Their combinations (HUAE and UHAE) enhance the damage to the cell wall of raw materials and improve the extraction efficiency by the synergistic effect. The results showed that using 60% acetone (V : V) as extraction solvent, solid-liquid ratio of 1:5 g mL^-1, ultrasonic temperature of 80 ℃, ultrasonic time of 80 min, ultrasonic power of 225 W, and then homogenizing at 10,000 rpm for 10 min, the total flavonoid content of CM reached the maximum value of 551.99 ± 12.69 mg Rutin g^-1 dry weight (dw), while the total phenolic content reached the maximum value of 289.48 ± 4.41 mg GAE g^-1 dw at 10,000 rpm for 5 min, which may be related to the oxidative degradation of polyphenols caused by the increase of polyphenol oxidase with the extension of homogenization time. This study provides a technical guarantee for the further utilization of phenolic substances in CM.

Persicaria strigosa (R.Br.) Nakai: a natural anthelmintic?

Persicaria strigosa (R.Br.) Nakai. (Family Polygonaceae) is an important plant of Assam, having several ethnobotanical uses. Tribal communities consume leaf extracts to cure helminth infection. The present study investigated the antioxidant, phytochemicals, and anthelmintic activity of P. strigosa. Total phenolic and flavonoid contents were estimated following standard methods. Antioxidant properties were analyzed by TAC, FRAP, DPPH, ABTS, and TBARS assays. Anthelmintic activity of plant was investigated in Paramphistomum sp. treated with 5 mg/mL, and paralysis and death times were recorded. The most potent solvent extract was performed GC-MS analysis to identify the phytocompounds. Plant extract-treated parasites were further analyzed for biochemical changes. Additionally, molecular docking was performed to study the binding affinities between phytocompounds and enzymes. P. strigosa showed rich phenolics, flavonoids, and antioxidant properties. Ethyl acetate and methanolic extracts showed more powerful antioxidant properties than other extracts. In vitro anthelmintic study found ethyl acetate and diethyl ether the most active extracts. Treated parasites showed a significant decrease in enzyme activity. The highest inhibition was observed in AchE, followed by MDH, LDH, ALP, and ACP. GC-MS study identified 12 probable compounds from the ethyl acetate extract of P. strigosa. Molecular docking showed the strongest binding affinity between the phytocompounds and AchE enzyme (- 7.6 kcal/mol). Overall, compounds C6, C7, and C12 showed better binding affinity compared to other compounds. The in vitro helminth bioassays and biochemical analysis suggest Persicaria strigosa a possible anthelmintic agent. However, isolation and characterization of bioactive compound(s) may promise new drug candidates for helminth infections.

Antioxidant and Antiproliferative Activity of Selected Medicinal Plants of Lower Assam, India: An In Vitro and In Silico Study

BACKGROUND

The use of medicinal plants for general wellbeing and disease treatment is a common practice among tribal communities of Kokrajhar districts of Assam. However, little works have been done to study the pharmacological aspect of the plants.

OBJECTIVES

The present study intends to study the antioxidant and antiproliferative properties of selected medicinal plants used by the tribal communities of the Kokrajhar district of Assam since ancient times.

METHODS

Five traditionally important medicinal plants, namely, Cassia fistula, Citrus grandis, Lindernia crustacea, Sacciolepis myosuroides, and Zingiber zerumbet were investigated for antioxidant, antiproliferative (cytotoxic) and apoptosis-inducing potential in the malignant cancer cell line. Phytochemical content, such as phenolic and flavonoid content, were estimated following standard protocol. The methanolic extract of plants was investigated following the phosphomolybdate method (TAC), FRAP, DPPH, ABTS, and TBARS assays. Antiproliferative activities of the plants were carried out by MTT assay in DL and PBMC cells. The apoptotic study was carried out following the acridine orange and ethidium bromide staining method and fluorescent microscopic imaging. Based on the significant (P≤0.05) high apoptotic inducing potential of the plant and to further dissect the molecular mode of action, including downstream biological action, major phytochemicals derived from L. crustacea were investigated for its prospective binding affinity with anti-apoptotic cancer target proteins.

RESULTS

Antioxidant studies by FRAP, DPPH, ABTS, and TBARS assay revealed that all five plants contain considerable free radical scavenging activity. C. fistula showed the strongest free radical scavenging activity while the fruit peel extract of C. grandis showed poor activity. The overall antioxidant activities of plants such as TAC, FRAP, DPPH, ABTS, and TBARS may be arranged in decreasing activity as C. fistula > Z. zerumbet > L. crustacea > S. myosuroides > C. grandis. MTT based cell proliferation study showed that all the plants extract significantly (P≤0.05) inhibited cell viability with negligible cytotoxicity (~5-12%) in normal cells. Moreover, L. crustacea showed promising antiproliferative and apoptosis-inducing ability against Dalton's lymphoma. It is worth mentioning that the major bioactive compounds of the most potent plant extract, L. crustacea interacted with anti-apoptotic proteins (cancer target) with higher affinity and the results are compared with reference inhibitors.

CONCLUSION

It is worth noting that these plants have the potential to consider for further scientific studies in different cell lines and animal models. Furthermore, isolation and characterization of bioactive compound(s) may promise the discovery of new and valuable drugs candidate to tackle various human diseases.

A Prospective of Multiple Biopharmaceutical Activities of Procyanidins-Rich Uapaca togoensis Pax Extracts: HPLC-ESI-TOF-MS Coupled with Bioinformatics Analysis

The article reports the chemical composition, antioxidant, six key enzymes inhibitory and antimicrobial activities of two solvent extracts (water and methanol) of leaves and stem bark of Uapaca togoensis. For chemical composition, methanol extract of stem bark exhibited significant higher total phenolic (129.86 mg GAE/g) and flavanol (10.44 mg CE/g) contents. Methanol extract of leaves and water extract of stem bark showed high flavonoids (20.94 mg RE/g) and phenolic acid (90.40 mg CAE/g) content, respectively. In addition, HPLC-ESI-TOF-MS analysis revealed that U. togoensis was rich in procyanidins. The methanol and water extracts of stem bark had overall superior antioxidant activity; however, only methanol extract of stem bark showed higher inhibition of cholinesterase (AChE: 2.57 mg GALAE/g; BChE: 4.69 mg GALAE/g), tyrosinase (69.53 mg KAE/g) and elastase (2.73 mmol CE/g). Potent metal chelating ability was showed by water extract of leaves (18.94 mg EDTAE/g), higher inhibition of amylase was detected for water extracts of leaves (0.94 mmol ACAE/g) and stem bark (0.92 mmol ACAE/g). The tested extracts have shown wide-spectrum antibacterial properties and these effects have shown to be more effective against Aspergillus ochraceus, Penicillium funiculosum, Trichoderma viride, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The results revealed that the antioxidant, enzyme inhibitory and antimicrobial activities depended on the extraction solvents and the parts of plant. Bioinformatics analysis on the 17 major compounds showed modulation of pathway associated with cancer. In brief, U. togoensis might be valuable as potential source of natural agents for therapeutic application.

Biogenic Silver Nanoparticles of Clinacanthus nutans as Antioxidant with Antimicrobial and Cytotoxic Effects

Silver nanoparticles (AgNPs) previously synthesised using leaf (AgNP-L) and stem (AgNP-S) extracts of Clinacanthus nutans (C. nutans) were tested to evaluate antimicrobial, antioxidant, and cytotoxicity activities. The AgNPs showed good inhibition against bacteria, but not fungi. The inhibition results showed the highest activity against Staphylococcus aureus (S. aureus) with 11.35 mm (AgNP-L) and 11.52 mm (AgNP-S), while the lowest inhibition was against Escherichia coli (E. coli) with 9.22 mm (AgNP-L) and 9.25 mm (AgNP-S) in the disc diffusion method. The same trend of results was noted in the well diffusion method. The IC50 of AgNP-L and AgNP-S in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays was 417.05 μg/mL and 434.60 μg/mL, as well as 304.31 μg/mL and 326.83 μg/mL, respectively. Ferric reducing power (FRAP) assay showed that AgNP-L [872.389 μmol/L Fe(II)] and AgNP-S [612.770 μmol/L Fe(II)] exhibited significantly (p < 0.05) greater antioxidant activities than leaf extract (CNL) [152.260 μmol/L Fe(II)] and stem extract (CNS) [110.445 μmol/L Fe(II)] of C. nutans. The AgNPs were also proven to possess cytotoxic effects on the breast (MCF-7), cervical (HeLa), and colon (HT-29) cancer cells in a dose-dependent manner. AgNP-S and AgNP-L showed significantly (p < 0.05) higher cytotoxicity against MCF-7 (117.43 μg/mL) and HT-29 (78.47 μg/mL), respectively. In conclusion, the biosynthesised AgNPs from aqueous extract leaves and stem of C. nutans have demonstrated promising potential towards antioxidant, antimicrobial, and cytotoxicity activities.

Facile production of chlorophyllides using recombinant CrCLH1 and their cytotoxicity towards multidrug resistant breast cancer cell lines

The purity of chlorophylls plays one of the key role for the production of chlorophyllides. We have designed a facile method for chlorophyll purification by twice solvent extraction. Twice extraction causes the loss of chlorophylls, but the purity of total chlorophylls can be enhanced 182%. Then, the purified chlorophylls can be converted to relatively pure chlorophyllides facilely. The results show that higher purity of chlorophyllides could be obtained when purified chlorophylls (ethanol-hexane extract) was used as starting materials than that of crude chlorophylls (ethanol-only extract). In biocompatibility test, the results showed that the prepared chlorophyllides can be applied as biomaterials. When the prepared chlorophyllides were applied to anticancer tests, they were active both in MCF7 and MDA-MB-231 (multidrug resistant breast cancer cells) cell lines. In addition, the results suggested that the prepared chlorophyllides could be a potential candidate of combination therapy with doxorubicin to breast cancers.

In Vitro Anthelmintic Activity of Ethanol Stem Bark Extract of Albizia ferruginea (Guill. & Perr.) Benth

Albizia ferruginea (Guill. & Perr.) Benth bark is used in the traditional medicine as a vermifuge. This study sought to determine the anthelmintic activity of the stem bark extract of Albizia ferruginea. The powdered A. ferruginea stem bark was extracted with ethanol. Phytochemical screening was carried out on A. ferruginea ethanol extract (AFE) and then screened for its anthelmintic property against Pheretima posthuma and Haemonchus contortus using the adult motility assay. The effect of AFE and its fractions on the anthelminthic activity of mebendazole and albendazole were also determined using the adult worm (P. posthuma) motility assay. AFE showed a dose-dependent anthelmintic activity against P. posthuma and H. contortus. The least concentration of AFE (0.5 mg/mL) paralyzed and killed P. posthuma within 272.50 ± 12.42 min and 354.50 ± 5.06 min of exposure, respectively. AFE at the least test concentration (0.14 mg/mL) caused paralysis and induced death of H. contortus, after at 63.50 ± 2.98 and 254.96 ± 2.44 min of exposure, respectively. AFE extract at 0.25 and 0.125 mg/mL increased the paralytic and helminthicidal activities of albendazole. The paralytic and helminthicidal activities of mebendazole were reduced when combined with AFE (0.25 and 0.125 mg/mL). Among the three fractions obtained from AFE, the methanol fraction showed the highest anthelmintic activity. The methanol fraction at 0.5 mg/mL caused paralysis after 69.90 ± 0.15 min and death of worm after 92.53 ± 0.74 min of exposure. The petroleum ether and ethyl acetate fractions showed relatively low anthelmintic activity. Phytochemical screening of AFE revealed the presence of tannins, saponins, glycosides, alkaloids, and coumarins. The results from this study show that A. ferruginea possesses anthelmintic activity which gives credence to its folkloric use.

Extraction of phenolic compounds: A review

Phenolic compounds are parts of secondary metabolites mostly found in plant species with enormous structural diversities. They can exist as glycosides or aglycones; matrix or free-bound compounds; and comprising mostly polymerized or monomer structures. Additionally, these compounds are not universally dispensed within plants with varied stability. This has contributed to challenging extraction processes; implying that employing a single step or inappropriate extraction technique might change the recovery of phenolic components from the plant samples. Hence, it is important to select an appropriate extraction method so as to recover the targeted phenolic compounds. This is will helps to recover substantial yields from the sample matrix. Therefore, this review mainly focuses on the phenolic compounds and several methods of extraction that are used to obtaining them from plant materials. These extraction methods includes both conventional and unconventional techniques.

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Phenolic compounds from natural sources.

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Methods of extracting phenolic compounds.

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Selection of an appropriate extraction method to recover the targeted phenolic compounds from plant materials.

Chitosan and glyceryl monooleate nanostructures containing gallic acid isolated from amla fruit: targeted delivery system

Gallic acid, active constituent of amla fruit its natural abundance with beneficial multi actions in body make them attractive for clinical applications. In present study, we focused on extracting, separating and characterizing gallic acid from amla and further formulated into chitosan nanoparticles, so bring it to increase its aqueous solubility and thereby bioactivity. Gallic acid nanoparticles were prepared by using poloxamer 407, chitosan and Glyceryl Monooleate (GMO) using probe sonicator and high pressure homogenization method. Prepared nanoparticles were characterized by particle size, zeta potential, DSC, XRD, SEM, entrapment efficiency, loading content, in-vitro release and stability study. They showed approximately 76.80% encapsulation of gallic acid with average size of 180.8 ± 0.21 nm, and zeta potential +24.2 mV. The cumulative in vitro drug release upto 24 hrs 77.16% was achieved suggesting that from all our findings, it can be concluded that work will facilitate extraction, design and fabrication of nanoparticles for protection and sustained release of gallic acid particularly to colonic region.

In vitro antioxidant and antityrosinase activities of Manilkara kauki

Manilkara kauki L. Dubard is a tropical plant in the genus Manilkara of family Sapotaceae. This study investigated the total phenolic and flavonoid contents, and antioxidant and antityrosinase activities in different parts of M. kauki (fruits, leaves, seeds, stem barks and woods) and in fractions of stem barks. The total phenolic and flavonoid contents of the methanol and aqueous crude extracts of different parts of M. kauki ranged from 10.87 to 176.56 mg GAE (gallic acid equivalents) per gram of crude extract and 14.33 to 821.67 mg QE (quercetin equivalents) per gram of crude extract, resp. Leaves and stem barks exhibited higher total phenolic and flavonoid contents and antioxidant and anti-tyrosinase activities than fruits, seeds and woods. Stem barks were sequentially extracted with n-hexane, ethyl acetate, methanol and water and then the fractionated extracts were subjected to antioxidant and antityrosinase activities testing. The ethyl acetate and methanol extracts of stem barks exhibited higher total phenolic and flavonoid contents and antioxidant and antityrosinase activities than the n-hexane and aqueous extracts. Moreover, ethyl acetate extract of M. kauki stem exhibited the highest antityrosinase activity. It may be a potential source of tyrosinase inhibitors for pharmaceutical and cosmetic applications.

Evaluation of chemo-preventive efficacy of Ficus religiosa latex extract by flow cytometry analysis and gene expression studies performed by RT-PCR in various cell lines

Background

An extract of Ficus religiosa latex has been previously found to possess potent pharmacological activity with high antioxidant content phytochemical. The present research was conducted to investigate the chemo-preventive efficacy of latex extract on human breast adenocarcinoma MDA MB 231, human neroblastoma IMR 32, and human colorectal HCT 116 cell lines.

Results

The results showed that the latex crude extract induced cytotoxicity in all the selected cell lines with IC50 value 4.8 ± 1.13 μg/ml against the IMR 32 cell line. The cell cycle analysis results indicated the arrest and accumulation of cells at G1 phase in case of MDA MB 231 cells and HCT 116 cells whereas in the case of IMR 32 cells the arrest was in G2/M phase. The clear bands of fragments observed in DNA ladder experiments showed that apoptosis is induced by extracts in the cell lines. This could be correlated with the gene level expression studies on selected pro-apoptotic (p53 and caspase-3) and anti-apoptotic (Bcl-2, AKT) genes, which got upregulated and downregulated, respectively.

Conclusion

Based on the experimental evidence, Ficus religiosa contains phytochemicals with potent antitumor activities.

Critical analysis of biophysicochemical parameters for qualitative improvement of phytogenic nanoparticles

Conventional chemical approaches for synthesizing nanoparticles (NPs) may restrict their applicability as they are not eco-friendly, energetically efficient and often involve toxic reducing/capping agents; but phytonanotechnology enabled the synthesis of safe, inexpensive, highly biocompatible NPs. In this regard, thorough understanding of green components and the modulatory effects of different reaction conditions on the physicochemical parameters of green synthesized NPs would be a prerequisite, which is not depicted elsewhere. This review critically analyzes the relevant reaction conditions from their mechanistic viewpoints in plant-based synthesis of NPs arising fundamental issues which need to be determined carefully. The size, stability and surface chemistry of phytogenic NPs may be fabricated as a function of multiple interconnected reaction parameters and the plant species used. The therapeutic potential of phytogenic NPs may depend on the plant species used; and so the meticulous understanding of physicochemical parameters and the family wise shorting of elite plant species may potentially benefit the theranostic future of plant-based NPs.

A Comparative Study on Phenolic Content, Antioxidant Activity and Anti-Inflammatory Capacity of Aqueous and Ethanolic Extracts of Sorghum in Lipopolysaccharide-Induced RAW 264.7 Macrophages

Sorghum is an important cereal with diverse phenolic compounds that have potential health promoting benefits. The current study comparatively characterized the phenolic contents of two novel black-seeded sorghum lines (SC84 and PI570481) using different extraction systems (water, ethanol and their acidified counterparts) and evaluated their antioxidant and anti-inflammatory activities. Phenolic compositions were determined by spectrophotometric assays and HPLC analysis. Antioxidant activities were assessed by radical scavenging effects on nitric oxide (NO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals, and the oxygen radical absorbance capacity (ORAC). Anti-inflammatory capacity was estimated by measuring levels of pro-inflammatory markers produced by lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Results showed that effects of solvent types and HCl on extraction efficiency differed among phenolic compounds and sorghum samples. Tannins were the most dominant polyphenols in the studied extracts (11.11-136.11 mg epicatechin equivalent/g sorghum). Sorghum extracts exerted more potent scavenging activity on DPPH than NO radicals. In LPS-activated RAW264.7 cells, sorghum extracts dose-dependently inhibited the production of NO, interleukin-6 (IL-6), and intracellular reactive oxygen species (ROS), with ethanolic extracts showing greater anti-inflammatory activity. Positive correlations were noted between tannin content and DPPH radical scavenging activity, and anti-inflammatory capacity. These results suggest the potential role of tannin-rich sorghum extracts against inflammation and associated diseases.

Reducing Sugar, Total Phenolic Content, and Antioxidant Potential of Nepalese Plants

The aim of the present study was to investigate the reducing sugar, total phenolic content, and in vitro antioxidant activity of 70% (v/v) ethanolic extract of seven medicinal plants grown in Nepal. The reducing sugar content and total phenolic content were determined by 3,5-dinitrosalicylic acid (DNSA) and the Folin–Ciocalteu method, respectively. The in vitro antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The reducing sugar content of the studied plant samples ranged from 6.89 ± 2.44 to 674.13 ± 2.43 mg GE/g dry extract weight and the total phenolic content ranged from 14.87 ± 0.41 to 281.71 ± 1.47 mg GAE/g dry extract weight. The reducing sugar and total phenolic content were found highest in Ficus glaberrima. Antioxidant activity was found highest in Melastoma malabathricum (IC₅₀value = 6.27 μg/mL), followed by F. glaberrima (IC₅₀value = 11.7 μg/mL). A positive and significant correlation was found between (i) total phenolic content and reducing sugar content and (ii) total phenolic content and antioxidant activity. The present study is the first study for the analysis of reducing sugar content of selected plants and for the scientific exploration of F. glaberrima. The present result suggests that the various parts of these studied plants could be assumed as a rich source of biologically active compounds and considered beneficial for the food and pharmaceutical industries.

Evaluation of solvent and temperature effect on green accelerated solvent extraction (ASE) and UHPLC quantification of phenolics in fresh olive fruit (Olea europaea)

A green ASE (accelerated solvent extraction) with a shorter UHPLC (ultra-high performance liquid chromatography) method was developed for simultaneous determination of phenolics. High extract yield (130 mg/g) was observed for water at 100 °C in a short time of 19.5 min using 33.5 mL solvent whereas, UHPLC showed more phenolics of GA (gallic acid), QT (quercetin), LT (luteolin) in ACE (acetone) and RT (rutin) in EtOH (ethanol) solvent at 60 °C. The binary solvent system of ACE: EtOH (1:1) at 60 °C was optimized as extraction set. UHPLC runtime was 3 min with retention times of (min); 0.63 (GA), 0.97 (RT), 2.00 (QT) and 2.41 (LT). Average for phenolics (ppm) was, QT (10.91) > GA (7.33) > LT (4.10) > RT (3.90) whereas, Spanish whole green olive (SP2) showed more phenolics (20.72). Individual phenolic was, GA (47.06) > RT (26.21) > QT (19.34) > LT (6.18). Multivariate, K-mean and PCA (principal component analysis) for solvent*extract yield showed significant correlation and temperature showed no significant correlation for phenolics.

A Comparative Bio-Evaluation and Chemical Profiles of Calendula officinalis L. Extracts Prepared via Different Extraction Techniques

Calendula officinalis L., (marigold), well known for its medicinal properties, has been extensively studied for its therapeutic properties. Nonetheless, as far as the literature could establish, no study has attempted to comparatively assess the biological (antioxidant and enzyme inhibitory potential) of the flowers, leaves, and roots of C. officinalis extracted using conventional (maceration and Soxhlet extraction (SE)) and non-conventional extraction (homogenizer (HAE) and ultrasound (UAE) assisted extraction) techniques. The detailed phytochemical profile of each extract along with the concentration of specific bioactive compounds has also been established. Total phenolic content was highest for the flower extracts while flavonoid content was highest in the leaf extracts. Phytochemical profiling showed that the extraction method influenced the phytochemical composition of the extract. Nicotiflorin was identified in the flower extracts only while amentoflavone occurred only in the roots, inferring that the occurrence of bioactive compounds varies within a plant. The flower extracts showed highest antioxidant potential while the roots extracts were potent inhibitors of cholinesterase and tyrosinase. This study provides valuable data on the influence of extraction techniques on the recovery of bioactive compounds from plants. In an endeavor to scale-up extraction from plant considering the more efficient extraction method is of paramount importance. Moreover, the study highlighted the necessity to thoroughly examine the biological activities of various parts of a plant obtained via different extraction protocols.

Xanthine Oxidase Inhibition, In Vitro Antioxidant Activity and Antibacterial Effect of the Aerial Part Extracts of Thymus pallidus Coss

Background:

The Algerian medicinal plant Thymus pallidus Coss. is traditionally known to be used as an anti-infective, expectorant, healer of wounds and against inflammatory and gastrointestinal diseases.

Objective:

The aim of the present study is to investigate the antioxidants and the antibacterial activities of the aerial part extracts of this plant.

Methods:

Polyphenols extraction was performed with methanol 85%, followed by preliminary fractionation based on the polarity of the solvent. The extraction and fractionation process gave the crude extract (CrE), chloroform extract (ChE), ethyl acetate extract (EtAE) and aqueous extract (AqE). The antioxidant activity of extracts was evaluated using in vitro assays. While the antimicrobial activity was determined using disk diffusion method.

Results:

Quantitative analysis of polyphenol and flavonoids showed that EtAE includes the highest amount (P≤0.001) with 495.12±1.91 μg GAE/mg of extract and 97.25±2.84 μg QE/mg of extract, for both polyphenols and flavonoids respectively. The results of the antioxidant activity of extracts showed that the EtAE exhibited the highest inhibition activity on XO (IC50 =51.6±0.2 μg/ml) compared to other extracts (P≤0.001). Moreover, the EtAE was the most effective fraction in free radical scavenging assay against ABTS radical and hydrogen peroxide (EC50= 3.21±0.03 μg/ml and EC50 =12.12±0.05 μg/ml, respectively) compared to other extracts (P≤0.01). Using β-carotene/ linoleic acid bleaching assay, the AqE and ChE recorded a considerable inhibition effect on linoleic acid oxidation with a ratio of 81.81% and 80.86%, respectively. In the antimicrobial activity evaluation, the extracts exhibited moderate antibacterial activity against bacterial strain, with inhibition zone ranging from 07 to 14 mm. In addition, the EtAE showed a good action spectrum against six bacterial strains. In conclusion, the EtAE of Thymus pallidus showed good antioxidant activity and antibacterial effect.

Conclusion:

The obtained results revealed the presence of a strong correlation between the antioxidant and antibacterial activities of the extract and its total phenolic content. Furthermore, they reported that the EtAE has a considerable antioxidant capacity. This can be considered as an alternative natural source of antioxidants used generally as additives in food and pharmaceutical preparation.

Optimization of biogenic synthesis of silver nanoparticles from flavonoid-rich Clinacanthus nutans leaf and stem aqueous extracts

Background: Silver nanoparticles (AgNPs) are widely used in food industries, biomedical, dentistry, catalysis, diagnostic biological probes and sensors. The use of plant extract for AgNPs synthesis eliminates the process of maintaining cell culture and the process could be scaled up under a non-aseptic environment. The purpose of this study is to determine the classes of phytochemicals, to biosynthesize and characterize the AgNPs using Clinacanthus nutans leaf and stem extracts. In this study, AgNPs were synthesized from the aqueous extracts of C. nutans leaves and stems through a non-toxic, cost-effective and eco-friendly method. Results: The formation of AgNPs was confirmed by UV-Vis spectroscopy, and the size of AgNP-L (leaf) and AgNP-S (stem) were 114.7 and 129.9 nm, respectively. Transmission electron microscopy (TEM) analysis showed spherical nanoparticles with AgNP-L and AgNP-S ranging from 10 to 300 nm and 10 to 180 nm, with average of 101.18 and 75.38 nm, respectively. The zeta potentials of AgNP-L and AgNP-S were recorded at -42.8 and -43.9 mV. X-ray diffraction analysis matched the face-centred cubic structure of silver and was capped with bioactive compounds. Fourier transform infrared spectrophotometer analysis revealed the presence of few functional groups of phenolic and flavonoid compounds. These functional groups act as reducing agents in AgNPs synthesis. Conclusion: These results showed that the biogenically synthesized nanoparticles reduced silver ions to silver nanoparticles in aqueous condition and the AgNPs formed were stable and less toxic.

Phytochemical and antioxidant profiling of Ocimum sanctum

The leaves of Ocimum sanctum were extracted in methanol (OsM) and sequentially fractionated with n-hexane (OsH), ethylacetate (OsE) and butanol (OsB) to find the best extraction solvent for antioxidants from the herb known for its medicinal values. OsB was rich in both total polyphenolic content (TPC) (212.26 ± 6.3 mg GAE/g extract) and total flavonoid contents (TFC) (54.51 ± 3.5 mg QE/g extract). OsE also had significantly high TPC (202.71 ± 5.5 mg GAE/g extract). The EC₅₀ based on DPPH (3.91 ± 0.3 μg/ml), ABTS (1.6 ± 0.1 μg/ml) and phosphomolybdate (2.31 ± 0.1 μg/ml) for OsB; hydroxyl (5.3 ± 0.4 μg/ml), superoxide (7.32 ± 0.9 μg/ml) radicals for OsM and DPPH (8.61 ± 0.6 μg/ml), phosphomolybdate (2.43 ± 0.1 μg/ml) and ABTS (5.3 ± 0.4 μg/ml) for OsE were lower than ascorbic acid showing potential antioxidant properties. EC₅₀ values of different fractions for DPPH anion, ABTS cation free radical scavenging and phosphomolybdate reducing property were significantly and positively correlated with TPC and TFC. LC-MS analysis of OsB and OsE showed the presence of luteolin, apigenin, rosmarinic, chlorogenic, caffeic acid and their derivatives. Quercetin is extracted in ethylacetate fraction. Overall data revealed that O. sanctum leaf extracts in butanol and ethylacetate with high polyphenolics and flavonoids, had strong antioxidant potential.

Anti-melanogenic activity of Myristica fragrans extract against Aspergillus fumigatus using phenotypic based screening

Background

Aspergillus fumigatus, an opportunistic fungal pathogen is associated with a wide array of diseases. It produces 1, 8-dihydroxy naphthalene (DHN) melanin that imparts greenish grey color to conidia and is an important virulence factor. It masks various molecular patterns associated with A. fumigatus and protects the fungus from host immune system. Myristica fragrans, enriched with secondary metabolites has been traditionally used for the treatment of infectious and inflammatory diseases. The present study was aimed to explore the anti-melanogenic effect of M. fragrans extracts on A. fumigatus.

Methods

M. fragrans extracts (hexane, chloroform, methanol and ethanol) were prepared through polarity guided extraction. Phytochemical analysis was performed to detect the chemical constituents of the extracts. The minimum effective concentration (MEC) of the extracts against A. fumigatus melanin was determined by broth micro-dilution assay. Various virulence factors were assayed by spectrophotometric methods. Electron microscopic studies were performed to evaluate the effect of the hexane extract of M. fragrans on A. fumigatus cell surface morphology. The major active compounds of the extract were detected by gas chromatography-mass spectrometry (GC-MS). Docking was performed to study the interaction between the major identified compounds and the ketosynthase domain of polyketide synthase protein.

Results

The results indicated that the hexane extract of M. fragrans inhibited melanin production (76.09%), reduced ergosterol content (83.63%) and hydrophobicity of the cell (72.2%) at the MEC of 0.078 mg/mL. Altered conidial surface, disappearance of protrusions and absence of melanin layer on outer cell surface was observed in electron microscopy. Forty-two compounds were identified by GC-MS. The main constituents were identified as sabinene (12.2%), linoleic acid (11.7%), hexadecanoic acid (10.5%), safrole (8.1%) and elemicin (7.8%). Docking studies revealed that hexadecanoic acid, its derivative compound cis-9-hexadecenal and isoeugenol have lower binding energy forming proper hydrogen bond with ketosynthase domain of polyketide synthase protein.

Conclusion

The study concludes that the extract of M. fragrans has potential antifungal properties that can be explored in combination with available antifungals. This combination approach may be helpful for large number of patients suffering with A. fumigatus infections.

Effects of Different Factors on Concentration of Functional Components of Aronia and Saskatoon Berries

Effects of different factors on the content of phenolics, anthocyanins, antioxidants and colour parameters in two varieties of Aronia and three varieties of Saskatoon berries were evaluated. The berries were extracted by dynamic solvent extraction using three different solvents (water, 50% ethanol (v/v) and dimethyl sulfoxide) and subsequently analysed by ultraviolet visible near infrared spectroscopy and electron paramagnetic resonance followed by chemometric analysis. The results obtained show that, dimethyl sulfoxide was the most appropriate for berries functional components isolation, and among the studied berries, Aronia exhibited the highest contents of phenolics. Besides that, varieties of Aronia melanocarpa Viking and of Amelanchier lamarckii Ballerina were selected as the cultivars with high contents of functional components. Satisfactory differentiation of berries was achieved according to extraction solvent, fruit type, variety and production years. The results obtained reveal that, phytochemical composition of Aronia and Saskatoon berries may vary depending on genotypic factors, climate, growing conditions as well as on extraction method used for their assessment. Sample processing, genotypic and seasonal factors had significant effect on the concentration of naturally occurring compounds in berries.

Antiviral activity of five filamentous cyanobacteria against coxsackievirus B3 and rotavirus

Coxsackievirus B3 (CVB3) and rotavirus (RV) are pathogens of some chronic human diseases. The aim of this study was to determine in vitro antiviral activity of some cyanobacteria against RV and CVB3 infections. Five cyanobacteria were collected from Egypt, identified, and analyzed biochemically. Then, the inhibition of the cytopathic effect of RV and CVB3 viruses by cyanobacterial extracts was examined. Methanol extract of the cyanobacterial isolates showed high antiviral activity against CVB3 with Therapeutic index (TI) of 50.0, 30.0, 27.6, 16.6, and 20.0 for Leptolyngbya boryana, Arthrospira platensis, Nostoc punctiforme, Oscillatoria sp., and Leptolyngbya sp., respectively. The extracts reduced CVB3 titers comparing to 50% tissue culture infectious doses (TCID₅₀) with values 3.25-5.75 log₁₀ of TCID₅₀. Moreover, extracts of A. platensis, and Oscillatoria sp. exhibited high antiviral activity against RV with TI values of 45 and 42.5, respectively, and a reduction in virus titers by 5.75 log₁₀ and 5.5 log₁₀ of TCID₅₀, respectively. Extracts of L. boryana, Leptolyngbya sp., and N. punctiforme had a moderate to low antiviral activity against RV with TI ranging between 2.8 and 7, respectively, and a reduction in virus titers between 0.5 log₁₀ and 1.5 log₁₀ of TCID₅₀, respectively. This study concluded that extracts of five cyanobacterial isolates possess a potent antiviral effect against CVB3 and RV, making them promising sources of new safe antiviral drugs.

Phytochemical and Antioxidant Activities of Cucumis africanus L.f.:: A Wild Vegetable of South Africa

Objective.

To evaluate the phytochemical content and antioxidant potential of the acetone, aqueous, and methanol extracts of the fruit, leaf, and root of Cucumis africanus L.f.

Methods.

Total phenolic, flavonoid, and proanthocyanidin contents were evaluated using spectrophotometric methods. The free radical scavenging activity of the acetone, methanol, and aqueous extracts of the fruit, leaf, and root were evaluated against DPPH⁺, ABTS⁺, and phosphomolybdenum. Alkaloid and saponin contents were also determined.

Results.

The acetone extract of the fruit revealed the highest polyphenol content when compared with the other solvent extracts analyzed. Total phenol content of the parts tested ranged from 3.66 ± 0.17 to 44.98 ± 3.41, flavonoid content ranged from 4.63 ± 3.33 to 401.33 ± 7.89, and proanthocyanidin content ranged from 8.84 ± 2.65 to 504 ± 36.6. Significant amount of alkaloids present was observed in the fruits, leaf, and root (10.68 ± 0.68, 14.12 ± 1.67, and 12.15 ± 4.74), respectively, while saponin content was 33.33 ± 11.55, 26.67 ± 11.55, and 20.00 ± 0.00 for the fruit, leaf, and root, respectively. Solvent extracts showed significant antioxidant activity, with acetone showing highest antioxidant ability in correlation with the polyphenol contents. Based on the IC₅₀ values, acetone extract of the root revealed the best DPPH radical scavenging ability, the leaf aqueous extract had the highest IC₅₀ value for ABTS, and the methanol extract of the leaf was best for phosphomolybdenum assays.

Conclusion.

This study suggests that fruit, leaf, and root of Cucumis africanus could be a potential source of natural antioxidant and justifies its use in ethnomedicine.

In vitro and in vivo anti-diabetic and anti-oxidant activities of methanolic leaf extracts of Ocimum canum

Background:

Diabetes is a metabolic disorder with a highly complex, multifaceted and intricate etiologies and thus may require management options that proffers multimodal mechanism of action. This present study evaluated the antidiabetic and antioxidant potential of the methanolic extract/fractions of leaves of Ocimum canum.

Methods:

The antidiabetic potential was evaluated and using STZ-induced diabetic Wistar rat model (in vivo) and inhibition of α-amylase and α-glucosidase activity (in vitro). Antioxidant activity was assessed in vitro by free radical scavenging and reducing power assays and in vivo via monitoring SOD and CAT activities; GSH and MDA levels.

Results:

The total phenolic content (221.0±3.0 mg catechol/g of sample) and tannins (146.0±4.0 mg tannic acid/g of sample) of the crude extract; and flavonoid of the aqueous-methanol fraction (216.0.0±1.0 mg of rutin/g of sample) were found to be significantly higher relative to others. The crude extract and the aqueous-methanol fraction exhibited a significantly (p<0.05) higher percentage reduction in fasting blood glucose and a concomitant increase in serum insulin level relative to the diabetic control group. The highest radical scavenging activity and reducing power were observed in the aqueous-methanol fraction. The aqueous-methanol solvent fraction also significantly reversed the alterations in oxidative stress markers occasioned by the diabetic condition.

Conclusion:

In conclusion, the result of the present study has demonstrated evidently that extracts of Ocimum canum leaves ameliorates hyperglycemia and the associated oxidative stress in STZ-induced rats.

Development of Caco-2 cells-based gene reporter assays and evaluation of herb-drug interactions involving CYP3A4 and CYP2D6 gene expression

The indiscriminate use of medicinal plants and herbal medicinal products concomitantly with conventional drugs may result in herb-drug interactions that may lead to fluctuations in drug bioavailability, therapeutic failure, and/or toxic effects. CYP450 enzymes play an important role in drug biotransformation and herb-drug interactions. Thus, the aim of this study was to develop and apply Caco-2 cells-based gene reporter assays to study in vitro the potential occurrence of CYP3A4 and CYP2D6 gene expression modulation by standardized extracts of selected medicinal plants. Reporter cell lines developed showed a significant increase in CYP3A4 and CYP2D6 reporter fluorescent emission, 4 and 16-fold respectively, when compared to the controls. The standardized extracts of Cecropia glaziovii, Bauhinia forficata and Echinacea sp. significantly increased CYP3A4 reporter fluorescence, and those of Ilex paraguariensis, Bauhinia forficata and Echinacea sp. significantly decreased CYP2D6 reporter fluorescence in Caco-2 cells-based gene reporter assays. The data obtained suggest that CYP3A4 and CYP2D6 gene expression seem to be modulated by the extracts tested. In addition, the reporter cell lines developed are functional assays that could be used to study drug-drug and herb-drug interactions during the research and development of new drugs.

Larvicidal activity of some medicinal plant extracts against filariasis fever mosquito, Culex quinquefasciatus (Say.) (Diptera: Culicidae)

OBJECTIVES

The present study was aimed to find the larvicidal activity of petroleum ether, chloroform, acetone and methanolic extracts of Dichanthium foveolatum (Del.) Roberty, Leptochloa uniflora Hochst, Pancratium triflorum Roxb and Molineria trichocarpa (Wight) N.P.Balakr against Culex quinquefasciatus.

METHODS

The larvicidal potential of selected plant extracts were determined against 4th instar larvae of C. quinquefasciatus with various concentrations viz., 50, 100, 150, 200 and 250 mg/ml. The mortality counts were made after 24 h of incubation and LC₅₀ values were calculated.

RESULTS

Chloroform extracts of studied plants were showed highest larvicidal activity with remarkable irritant against the larva of C. quinquefasciatus. Highest larvicidal activity was observed in the chloroform extract of D. foveolatum against the larva of C. quinquefasciatus with LC50 = 277.03 mg/ml. The larvicidal activity of the studied plants as follows chloroform extract of D. foveolatum (LC50 = 277.03 mg/ml) >L. uniflora (LC50 = 300.56 mg/ml) >M. trichocarpa (LC50 = 306.60 mg/ml) >P. triflorum (LC50 318.42 mg/ml). The larvicidal potential of P. triflorum was as follows Chloroform > acetone > methanol > petroleum ether. The larvicidal activities of L. uniflora and M. trichocarpa were as follows Chloroform > petroleum ether > acetone > methanol respectively. The larvicidal potentials of D. foveolatum was as follows Chloroform > methanol > acetone > petroleum ether.

CONCLUSION

The chloroform extract of D. foveolatum find use as broad-spectrum larvicidal agent in the near future. It is hoped that more work would be undertaken to evaluate the utility of these plant extracts for field applications considering the promising leads given by the present study.

Mechanism of Action against Food Spoilage Yeasts and Bioactivity of Tasmannia lanceolata, Backhousia citriodora and Syzygium anisatum Plant Solvent Extracts

Bioactive properties of solvent extracts of Tasmannia lanceolata, Backhousia citriodora and Syzygium anisatum investigated. The antimicrobial activities evaluated using agar disc diffusion method against two bacteria (Escherichia coli and Staphylococcus aureus) and six weak-acid resistant yeasts (Candida albicans, Candida krusei, Dekkera anomala, Rhodotorula mucilaginosa, Saccharomyces cerevisiae and Schizosaccharomyces pombe). The antioxidant activities determined using DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging and reducing power assays. Quantification of major active compounds using ultra-high performance liquid chromatography. Extracts showed broad-spectrum antifungal activity against weak-acid resistant yeasts in comparison to the standard antifungal agents, fluconazole and amphotericin B. Dekkera anomala being the most sensitive and strongly inhibited by all extracts, while Escherichia coli the least sensitive. Polygodial, citral and anethole are the major bioactive compounds identified in Tasmannia lanceolata, Backhousia citriodora and Syzygium anisatum, respectively. Hexane extracts contain the highest amount of bioactive compounds and demonstrate the strongest antimicrobial activities. Methanol and ethanol extracts reveal the highest phenolic content and antioxidant properties. Fluorescence microscopic results indicate the mechanism of action of Backhousia citriodora against yeast is due to damage of the yeast cell membrane through penetration causing swelling and lysis leading to cell death.