Chemical Composition and Biological Activities of the Essential Oil from Citrus reticulata Blanco Peels Collected from Agrowastes

Citrus fruits have a thick outer coat which is often discarded due to its low economic value and usually contributes to the waste. So this work focused on exploring the potential pharmacological properties of the discarded citrus peels. In the present study, we extracted the essential oil from peel wastes of Citrus reticulata Blanco (CREO) from the local market. The antioxidant, antibacterial, and anticancer properties of essential oil were evaluated. The CREO exhibited a strong antioxidant property with DPPH radical scavenging, ABTS radical scavenging, H2 O2 radical scavenging, Ferric reducing antioxidant power and for Lipid peroxidation inhibition respectively. Antibacterial properties of CREO was indicated against different pathogenic microbial strains like E. coli, P. aeruginosa, S. aureus, and S. enterica in terms of disc diffusion method and minimum inhibitory concentration (MIC). Further, anticancer properties studied on breast cancer cell lines MCF7 and MDA-MB-231 showed dose-dependent cytotoxicity with IC50 of 56.67±3.12 μg/mL and 76.44±2.53 μg/mL respectively. The GC-MS analysis of CREO revealed the presence of major compounds like S-limonene, α-pinene, α-myrcene, and cis-terpinene which might have played a significant role in strong antioxidant, antibacterial and anticancer properties. The study thus identified the potential health benefits of Citrus reticulata peel waste.

Polysaccharide from Thymelaea hirsuta L. leaves: Structural characterization, functional properties and antioxidant evaluation

In this study, we successfully extracted a new polysaccharide from Thymelaea hirsuta L., which we named THP, with a yield of 13.94 % through aqueous extraction. The polysaccharide comprises 46.83 % neutral sugars and 7.08 % uronic acids. This heteropolysaccharide contains glucose, glucuronic acid, rhamnose, arabinose, and galactose with relative molar ratios of 29.68: 25.73: 21.31: 13.47 and 9.8, respectively. Analysis of glycosylation positions via methylation and structural features using Fourier transform infrared (FT-IR) and solid-state nuclear magnetic resonance (ssNMR) spectroscopy revealed that THP has a repeating unit (1 → 3 and 1 → 4)-linked β-d-glucopyranosyl backbone, with the d-glucopyranosyl residue as the branch point at O-6. The scanning electron microscopy (SEM) examination showed ellipsoidal granules with smooth surface. This polysaccharide also has good foaming capacity and emulsion stability, and a water holding capacity of 1.81 g/g. The THP dispersion at 1 % showed shear thinning behavior, demonstrating that it is a promising natural additive in various food formulations. The polysaccharide also demonstrated significant antioxidant properties, with a total antioxidant capacity of 315 mg α-tocopherol equivalents/g and an IC50 value of 8.01 mg/mL using the β-carotene bleaching method, surpassing those of synthetic antioxidants. Additionally, when added at a concentration of 0.13 % to an oil/water emulsion system, THP effectively delayed lipid oxidation during storage at 37 °C. The kinetic study of THP-stabilized oil/water emulsion is anticipated to provide valuable insights for its future applications in food and pharmaceutical emulsions.

A novel chitosan antioxidant bearing sulfhydryl group: Synthesis, characterization and activity assessment

To improve the antioxidant activity, sulfhydryl groups (-SH) were introduced into chitosan. Acylated chitosan derivatives, chitosan cationic salt derivatives, hydroxypropyl trimethylammonium chloride chitosan quaternary ammonium salt (HACC) derivatives and N,N,N-trimethyl chitosan iodine (TMC) derivatives were obtained. The chitosan derivatives were characterized by FTIR and 1H NMR to confirm the successful synthesis. Ellman's reagent was used to determine that the compound contained free sulfhydryl groups. The water solubility and thermal stability of chitosan and derivatives were evaluated. The antioxidant activities of the derivatives were verified, including DPPH radical scavenging activity, superoxide anion radical scavenging activity and reducing power activity. The novel chitosan derivatives showed excellent antioxidant activities. Toxicity assay used L929 cells proved that the derivatives had no significant toxic. The results showed that the chitosan derivatives bearing sulfhydryl groups described in this paper has a certain antioxidant effect, which provides a practical approach for further study of chitosan.

Advanced hydrostable, recyclable and degradable cellulose hybrid films as renewable alternatives to synthetic plastics

Strong, tough and sustainable materials are in high demand in various engineering applications. We demonstrate a potential sustainable hybrid film made from natural cellulose and a biobased slurry. Through a simple and scalable approach, cellulose can be processed into an advanced material with over 2.8 and 9.2-fold increase in dry strength and toughness after curing and a 728-fold increase in wet strength, respectively. In addition, these hybrid composite films display an outstanding antioxidant activity surpassing 90 %, along with excellent ultraviolet radiation shielding and thermal insulation properties. Further, the hybrid films can be fabricated by integrating all-natural materials and still guarantee their unique functionality. We also demonstrate the feasibility of a circular bioeconomy by recycling the hybrid film using a green, deep eutectic solvent to fabricate a recycled hybrid film that displays excellent mechanical and optical properties. When recycling is unsuitable or economical, the hybrid film can naturally degrade in the soil under 6 months. These encouraging findings suggest the promise of cellulose hybrid films as a renewable, low-cost, tough, and strong material with the potential to replace nonrenewable synthetic plastics and products.

Effect of Pleurotus eryngii mycelial fermentation on the composition and antioxidant properties of tartary buckwheat

In this study, we investigated the effect of solid-state fermentation of Pleurotus eryngii on the composition and antioxidant activity of Tartary buckwheat (TB). Firstly, the solid-state fermentation of P. eryngii mycelium with buckwheat was carried out, and the fermentation process was explored. The results of the extraction process and method selection experiments showed that the percolation extraction method was superior to the other two methods. The results of extraction rate, active components and antioxidant activity measurements before and after fermentation of TB extract showed that the extraction rate increased about 1.7 times after fermentation. Total flavonoids, rutin and triterpene contents were increased after fermentation compared to control. Meanwhile, LC-MS results showed an increase in the content of the most important substances in the fermented TB extract and the incorporation of new components, such as oleanolic acid, ursolic acid, amino acids, and D-chiral inositol. The fermented TB extract showed stronger antioxidant activity, while the protein and amino acid contents increased by 1.93-fold and 1.94-fold, respectively. This research was the first to use P. eryngii to ferment TB and prepared a lyophilized powder that could be used directly using vacuum freeze-drying technology. Not only the use of solid-state fermentation technology advantages of edible fungi to achieve value-added buckwheat, but also to broaden the scope of TB applications. This study will provide ideas and directions for the development and application of edible mushroom fermentation technology and TB.

A newly discovered glycosyltransferase gene UGT88A1 affects growth and polysaccharide synthesis of Grifola frondosa

Grifola frodosa polysaccharides, especially β-D-glucans, possess significant anti-tumor, antioxidant and immunostimulatory activities. However, the synthesis mechanism remains to be elucidated. A newly discovered glycosyltransferase UGT88A1 was found to extend glucan chains in vitro. However, the role of UGT88A1 in the growth and polysaccharide synthesis of G. frondosa in vivo remains unclear. In this study, the overexpression of UGT88A1 improved mycelial growth, increased polysaccharide production, and decreased cell wall pressure sensitivity. Biomass and polysaccharide production decreased in the silenced strain, and the pressure sensitivity of the cell wall increased. Overexpression and silencing of UGT88A1 both affected the monosaccharide composition and surface morphology of G. frondosa polysaccharides and influenced the antioxidant activity of polysaccharides from different strains. The messenger RNA expression of glucan synthase (GLS), UTP-glucose-1-phosphate uridylyltransferase (UGP), and UDP-xylose-4-epimerase (UXE) related to polysaccharide synthesis, and genes related to cell wall integrity increased in the overexpression strain. Overall, our study indicates that UGT88A1 plays an important role in the growth, stress, and polysaccharide synthesis of G. frondosa, providing a reference for exploring the pathway of polysaccharide synthesis and metabolic regulation. KEY POINTS: •UGT88A1 plays an important role in the growth, stress response, and polysaccharide synthesis in G. frondosa. •UGT88A1 affected the monosaccharide composition, surface morphology and antioxidant activity of G. frondosa polysaccharides. •UGT88A1 regulated the mRNA expression of genes related to polysaccharide synthesis and cell wall integrity.

Exploring the antioxidant and antimicrobial potential of three common seaweeds of Saint Martin's Island of Bangladesh

Antioxidants, which have long been deemed an indispensable guardian of human health, play a pivotal role in bolstering the body's defense against a plethora of diseases. Three well-recognized seaweeds in Bangladesh, including Caulerpa racemosa, Padina tetrastromatica, and Hypnea musciformis, were subjected to meticulous analysis to reveal their phytochemical composition, antioxidant activity, and antimicrobial efficacy using advanced spectroscopic and disc diffusion methods. Intriguingly, we observed that C. racemosa emerges as frontrunners, possessing a substantial arsenal of phenol (143.08 ± 18.51 mg gallic acid equivalent g─1) and flavonoid (63.79 ± 2.16 mg rutin equivalent g─1). More fundamentally, C. racemosa exhibits a notable enrichment in the content of tannin (73.58 mg RE g─1) and chlorophyll (13.50 mg g─1), as well as, antioxidant capacity (4457.67 μg g─1). P. tetrastromatica, on the other hand, displayed commendable effectiveness in scavenging the DPPH radical, with percentages ranging from 53.98 to 62.17%. In terms of hydroxyl radical (OH•) scavenging activity, C. racemosa exhibited the highest efficacy at 400 g mL─1. Fascinatingly, C. racemosa exhibited an impressive antioxidant potential, as evidenced by its exceptionally low IC50 value of 5.58 μg mL-1 for OH• scavenging, whereas P. tetrastromatica showed impressively low value of 0.96 μg mL-1 for DPPH scavenging. Although the three seaweeds demonstrated limited efficacy against a spectrum of five human pathogenic bacteria, their potential as abundant sources of antioxidants remains unscathed. Notably, heatmap and PCA analysis revealed that C. racemosa and P. tetrastromatica emerge as the leading contender for studied antioxidant compounds, demonstrating their proclivity for antioxidant extraction, a trait that could be exploited for large-scale production of these valuable compounds.

Biogenic Ag2O nanoparticles with "Hoja Santa" (Piper auritum) extract: characterization and biological capabilities

The 'sacred leaf' or "Hoja Santa" (Piper auritum Kunth) has a great value for Mexican culture and has gained popularity worldwide for its excellent properties from culinary to remedies. To contribute to its heritage, in this project we proposed the green synthesis of silver oxide nanoparticles (Ag2O NPs) using an extract of "Hoja Santa" (Piper auritum) as a reducing and stabilizing agent. The synthesized Ag2O NPs were characterized by UV-Visible spectroscopy (plasmon located at 405 nm), X-ray diffraction (XRD) (particle size diameter of 10 nm), scanning electron microscopy (SEM) (particle size diameter of 13.62 ± 4.61 nm), and Fourier-transform infrared spectroscopy (FTIR) (functional groups from "Hoja Santa" attached to nanoparticles). Antioxidant capacity was evaluated using DPPH, ABTS and FRAP methods. Furthermore, the antimicrobial activity of NPs against a panel of clinically relevant bacterial strains, including both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Salmonella Enteritidis and Escherichia coli O157:H7), was over 90% at concentrations of 200 µg/mL. Additionally, we assessed the antibiofilm activity of the NPs against Pseudomonas aeruginosa (reaching 98% of biofilm destruction at 800 µg/mL), as biofilm formation plays a crucial role in bacterial resistance and chronic infections. Moreover, we investigated the impact of Ag2O NPs on immune cell viability, respiratory burst, and phagocytic activity to understand their effects on the immune system.

The effects of urban thermal heterogeneity and feather coloration on oxidative stress and metabolism of pigeons (Columba livia)

Urbanization stands out as a significant anthropogenic factor, exerting selective pressures on ecosystems and biotic components. A notable outcome of urbanization is thermal heterogeneity where the emergence of Urban Heat Islands is characterized by elevated air and surface temperatures compared to adjacent rural areas. Investigating the influence of thermal heterogeneity on urban animals could offer insights into how temperature variations can lead to phenotypic shifts. Urban pigeons (Columba livia) serve as an excellent model for studying urban thermal effects, given the melanism variations, which are associated with the pleiotropy of the melanocortin system. To examine the development of physiological plasticity in response to urban thermal variations, we conducted a study on pigeons in Santiago, Chile, during the rainy season. We assessed the influence of habitat on physiological traits related to metabolism and antioxidant capacities, which are theoretically affected by feather coloration. Our findings reveal that variations in melanism significantly impact pigeon physiology, affecting both antioxidant capacities and the mitochondrial activity of red blood cells. It was found that higher urban temperatures, from both the current sampling month and the prior sampling month (from CRU TS dataset), were negatively and strongly associated with lower antioxidant and metabolic activities. This suggests that elevated urban temperatures likely benefit the energetic budgets of pigeon populations and mitigate the negative effects of oxidative metabolism, with differential effects depending on feather colorations.

Comparative morpho-physiological and biochemical responses of Capsicum annuum L. plants to multi-walled carbon nanotubes, fullerene C60 and graphene nanoplatelets exposure under water deficit stress

Water deficit stress is one of the most significant environmental abiotic factors influencing plant growth and metabolism globally. Recently, encouraging outcomes for the use of nanomaterials in agriculture have been shown to reduce the adverse effects of drought stress on plants. The present study aimed to investigate the impact of various carbon nanomaterials (CNMs) on the physiological, morphological, and biochemical characteristics of bell pepper plants subjected to water deficit stress conditions. The study was carried out as a factorial experiment using a completely randomized design (CRD) in three replications with a combination of three factors. The first factor considered was irrigation intensity with three levels [(50%, 75%, and 100% (control) of the field capacity (FC)] moisture. The second factor was the use of carbon nanomaterials [(fullerene C60, multi-walled carbon nanotubes (MWNTs) and graphene nanoplatelets (GNPs)] at various concentrations [(control (0), 100, 200, and 1000 mg/L)]. The study confirmed the foliar uptake of CNMs using the Scanning Electron Microscopy (SEM) technique. The effects of the CNMs were observed in a dose-dependent manner, with both stimulatory and toxicity effects being observed. The results revealed that exposure to MWNTs (1000 mg/L) under well-watered irrigation, and GNPs treatment (1000 mg/L) under severe drought stress (50% FC) significantly (P < 0.01) improved fruit production and fruit dry weight by 76.2 and 73.2% as compared to the control, respectively. Also, a significant decrease (65.9%) in leaf relative water content was obtained in plants subjected to soil moisture of 50% FC over the control. Treatment with GNPs at 1000 mg/L under 50% FC increased electrolyte leakage index (83.6%) compared to control. Foliar applied MWNTs enhanced the leaf gas exchange, photosynthesis rate, and chlorophyll a and b concentrations, though decreased the oxidative shock in leaves which was demonstrated by the diminished electrolyte leakage index and upgrade in relative water content and antioxidant capacity compared to the control. Plants exposed to fullerene C60 at 100 and 1000 mg/L under soil moisture of 100 and 75% FC significantly increased total flavonoids and phenols content by 63.1 and 90.9%, respectively, as compared to the control. A significant increase (184.3%) in antioxidant activity (FRAP) was observed in plants exposed to 200 mg/L MWCNTs under irrigation of 75% FC relative to the control. The outcomes proposed that CNMs could differentially improve the plant and fruit characteristics of bell pepper under dry conditions, however, the levels of changes varied among CNMs concentrations. Therefore, both stimulatory and toxicity effects of employed CNMs were observed in a dose-dependent manner. The study concludes that the use of appropriate (type/dose) CNMs through foliar application is a practical tool for controlling the water shortage stress in bell pepper. These findings will provide the basis for more research on CNMs-plant interactions, and with help to ensure their safe and sustainable use within the agricultural chains.

Sustainable remediation of chromium-contaminated soils: boosting radish growth with deashed biochar and strigolactone

Chromium (Cr) stress significantly hinders crop production by disrupting nutrient uptake, impairing plant growth, and contaminating soil, posing a substantial threat to agricultural sustainability. The use of deashed biochar (DAB) and strigolactone can be an effective solution to mitigate this issue. Deashed biochar enhances crop production by improving soil structure, water retention, and nutrient availability while mitigating the bioavailability of toxic substances. Strigolactone boosts plant growth by stimulating root growth, branching, shoot formation, and overall plant physiology. Nevertheless, the scientific rationale behind their collective use as an amendment to counter Cr stress remains to be substantiated. Therefore, in this study, a blend of DAB and strigolactone was employed as additives in radish cultivation, both in the absence of Cr stress and under the influence of 200Cr stress. Four treatments, i.e., 0, 20µM Strigolactone, DAB, and 20µM Strigolactone + DAB, were applied in four replications following a completely randomized design. Results demonstrate that 20µM Strigolactone + DAB produced significant improvement in radish shoot length (27.29%), root length (45.60%), plant fresh weight (33.25%), and plant dry weight (78.91%), compared to the control under Cr stress. Significant enrichment in radish chlorophyll a (20.41%), chlorophyll b (58.53%), and total chlorophyll (31.54%) over the control under Cr stress, prove the efficacy of 20µM Strigolactone + DAB treatment. In conclusion, 20µM Strigolactone + DAB is the recommended amendment for mitigating Cr stress in radish. Farmers should consider using Strigolactone + DAB amendments to combat Cr stress and enhance radish growth, contributing to a more resilient agricultural ecosystem.

Antioxidant and anti-hepatitis A virus activities of Ecklonia cava Kjellman extracts

Ecklonia cava is a nutrient-rich algae species that contains abundant physiological phytochemicals, including peptides, carotenoids, fucoidans, and phlorotannins. However, elucidation of the antiviral effects of this algae and identification of new functional ingredients warrant further investigation. This study was aimed at investigating the potential anti-hepatitis A virus activities of extracts of E. cava prepared in different solvents. E. cava extracts were prepared using hot water and 70 % ethanol. The antioxidant activities of the extracts were confirmed by analyzing the total phenolic content, as well as 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activities. The inhibitory effects of the extracts against hepatitis A virus were analyzed using real-time polymerase chain reaction. The E. cava extract yield was 22.5-27.2 % depending on the extraction solvent. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was 70.44 % and 91.05 % for hot water and ethanol extracts at a concentration of 1000 ppm. The 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity of the ethanol extract was the highest (93.57 %) at 1000 μg/mL. Fourier-transform infrared was used to identify the functional groups (phlorotannin and alginate) in the extraction solvents. Ultra-high performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry analysis revealed a potential bioactive compound previously unidentified in E. cava. Finally, we identified the antiviral activity of E. cava extracts against hepatitis A virus replication. These findings demonstrate that E. cava could be used as an anti-hepatitis A virus functional food and biological material.

Development and quality evaluation of polyphenols enriched black carrot (Daucus carota L.) powder incorporated bread

Black carrot is a prominent source of polyphenols and the cheapest source of anthocyanins in India. In this study, an attempt has been made to examine the feasibility of black carrot powder as an ingredient in bread. Black carrot bread was prepared by incorporating different concentrations of black carrot powder (BCP) at 2.5, 5.0, 7.5 and 10 %. The developed bread samples were analyzed for physical and textural quality, proximate composition, bioactive compounds, antioxidant properties, sensory characteristics, mineral content and storage quality. The results revealed that loaf volume and specific volume decreased (1995-1254 mL, 5.25-3.28 mL/g) with the incorporation of BCP into bread. Textural analysis revealed that the addition of BCP led to increased hardness in the bread (0.110-12 0.151 N), whereas the resilience (43.64-35.10 %), cohesion and springiness (89.930-13 82.146 %) decreased significantly. The content of bioactive compounds such as total phenols, anthocyanins (29.63-112.68 mg/100 g) and flavonoids increased to exceptionally high levels in BCP-incorporated bread and showed high antioxidant activity. Incorporation of BCP up to 7.5 % showed the most acceptable sensory analysis score (7.85) with a significant increase in dietary fiber (40 %) and total mineral content (50 %), which revealed that black carrot powder could be used up to 7.5 % as an ingredient into bread with high acceptability. The present study revealed significant enhancement in bioactive compounds and mineral content of bread after the incorporation of black carrot powder, which supports its immense potential in preventing hunger and oxidative stress-induced disorders in developing countries.

Phenolic composition and antioxidant capacity of betel inflorescence extract in a simulated oral environment

The addition of betel inflorescence (BI) and slaked lime (calcium hydroxide) to betel quid (BQ) formulation may be detrimental to human health. Here, we assessed BI extracts prepared using artificial saliva or aqueous solution with or without adding slaked lime to mimic the release of phytochemicals from BI in the oral cavity. The extracts were also profiled by HPLC-DAD-ESI-QTOF-MS/MS to understand the quality and quantity of phytochemicals released. The results indicate that slaked lime facilitates the extraction of phenolics, likely due to a high pH. In a simulated oral environment with artificial saliva, the addition of slaked lime promotes the release of safrole, a well-known carcinogen. Dominant phytochemicals detected also include eugenol, acetyl eugenol and methyl eugenol, and only a fraction of these compounds is released in the simulated oral environment. This study reveals that environmental conditions can considerably affect the extraction of phytochemicals and triggers further investigation on how chewing practices may influence the release and activity of carcinogens.

Upcycling mango peels into a functional ingredient by combining fermentation and enzymatic-assisted extraction

This study aims at upcycling mango peels by a sequential application of enzymatic hydrolysis, using Viscozyme and Pectinex at 50 °C for 2 h; and fermentation, using L. plantarum and B. animalis at 48 h for 37 °C. The use of Viscozyme led to a considerable increase in the concentration of galacturonic and glucuronic acids in the unfermented samples (308.96 and 12.97 mg/100 ml higher than control, respectively), whereas the use of Pectinex resulted in higher oligosaccharide solubilization (5.3 % more than control). None of the enzymes influenced microbiological growth. The recovery of gallic acid aglycone increased 17-fold over the control when Pectinex and B. animalis were used. Similarly, the recovery of mangiferin aglycone increased by 60 % after fermentation by either bacteria. The results indicate that this sequential processing strategy might be utilized to extract phenolic aglycones and produce functional ingredients from mango peels.

Effects of Maillard reaction products on myoglobin-mediated lipid oxidation during refrigerated storage of carp

Lipid oxidation is the major cause of quality deterioration in freshwater fish, especially mediated by myoglobin (Mb). This study aimed to investigate the antioxidant mechanism of Maillard reaction products (MRPs) in Mb-mediated lipid oxidation in common carp (Cyprinus carpio). MRPs exhibited promising antioxidant and antimicrobial capacities based on the reduced content of peroxide and thiobarbituric acid-reactive substances and inhibited microbial growth. MRPs inhibited the oxidation of Mb by lowering the transfer from oxymyoglobin to metmyoglobin and improving the stability of heme iron. The correlation analysis showed that MRPs regulated the formation of free radicals by maintaining the reduced structure of Mb and the integrity of heme iron, and also directly inhibited the formation of oxidation products in a chain radical reaction. The texture and electronic nose analysis indicated that MRPs could delay the structural disruption and flavor deterioration of surimi. Therefore, MRPs could effectively inhibit Mb-induced lipid oxidation and further control the resulting changes in the flavor and texture of surimi.

Synthesis of anthraquinone-connected coumarin derivatives via grindstone method and their evaluation of antibacterial, antioxidant, tyrosinase inhibitory activities with molecular docking, and DFT calculation studies

Anthraquinones and coumarins have excellent pharmacological activities and are an important class of natural plant metabolites with various biological activities. In this study, anthraquinone-9,10-dione and coumarin derivatives were combined to develop a novel anthraquinone-connected coumarin-derivative sequence. The synthesised novel anthraquinone-connected coumarin derivatives (1a-t) were screened for in vitro antibacterial, antioxidant, and tyrosinase inhibitory activities. The antibacterial activities of the synthesised compounds (1a-t) were tested against both gram-positive and gram-negative bacteria. Specifically, compound 1t was more active against E. aerogenes than ciprofloxacin. With regard to antioxidant activity, compound 1o (50.68 % at 100 μg/mL) was highly active compared to the other compounds, whereas it was less active than the standard BHT (76.74 % at 100 μg/mL). In terms of compound 1r (9.31 ± 0.45 μg/mL) was highly active against tyrosinase inhibitory activity compared with kojic acid (10.42 ± 0.98 μg/mL). In the molecular docking study, compound 1r had a higher docking score (-8.8 kcal mol-1) than kojic acid (-1.7 kcal mol-1). DFT calculations were performed to determine the energy gap of highly active compound 1r (ΔE = 0.11) and weakly active compound 1a (ΔE = 0.12). In this study, we found that every molecule displayed significant antibacterial, antioxidant, and tyrosinase inhibitory properties. Based on these reports, compounds 1r and 1t may act as multi-target agents.

Development of lightweight, high-strength, and highly porous ligno-nanocellulosic foam with excellent antioxidant and insulation properties

This study reports an environmentally friendly ligno-nanocellulosic foam prepared by utilizing lignin (LGN), cellulose nanofiber (CNF), and citric acid (CA) as a green crosslinker through an easy, low-cost, and environmentally friendly process. The FTIR study and XPS analysis of the prepared LGN/CNF foams confirm the crosslinking between the components, which leads to lower shrinkage, lower density, and higher porosity than the neat CNF foam, achieving a remarkably low density of 19.59 mg/cm3 and high porosity of 98.84 % The morphology and microstructure of the foam show a uniform three-dimensional porous network built by strong cell walls. The crosslinked LGN/CNF foams indicate 182 % higher compressive modulus and 306 % higher compressive strength at 70 % strain than the neat CNF foam. Further, the addition of LGN and CA enhances the antioxidant activity of the foam. The prepared foam shows lower thermal conductivity and better sound absorption performance than the neat CNF foam, indicating a potential to be used as thermal insulation and sound-absorbing materials that can mitigate greenhouse gas emissions.

Enhancing the functionality of plant-based Yogurt: Integration of lycopene through dual-stage fermentation of soymilk

Well-defined compositional assemblies of plant-based yogurt are of fast-growing awareness for world population concerning environmental sustainability, economic burdens and health risks. Soybean is an attractive candidate for plant yogurt, suffering from poor flavor, limited nutrition, and undesired allergens to offer healthy-functional segments. Herein, we deciphered a novel lycopene-soy yogurt by efficient two-stage fermentation of engineered B. subtilis and LAB. The fortified sogurt was ensured with redundant lycopene of 22.67 ± 2.95 mg/g DCW by engineered B. subtilis and enriched soy isoflavone from synergistic effects of engineered B. subtilis and LAB, possessing strong antioxidant capacity for upgrading functionality. Moreover, the desired pH, accelerated protein hydrolysis, enhanced amino acid availability, and expected sensory attributes cooperatively conferred lycopene-soy yogurt as healthy functional food. High potential is firstly ascribed to sequential dual culture of engineered B. subtilis and LAB in lycopene-soy yogurt, in which flavorful, hypoallergenic and antioxidative ingredients enabled functionalities for plant-based yogurt.

Identification and evaluation of antioxidant peptides from highland barley distiller's grains protein hydrolysate assisted by molecular docking

The aim of this study was to identify antioxidant peptides from highland barley distiller's grains and evaluate their antioxidant activity in vitro. The results showed that the enzymatic hydrolysate of highland barley distiller's grains prepared by ultrasonic assisted alkaline protease had antioxidant properties, aromatic amino acids accounted for 61.48% of the total free amino acids and acidic/basic amino acids accounted for 40.82% of the total hydrolyzed amino acids in enzymatic hydrolysate. Ultrafiltration component F1 (Mw < 1 kDa) had the highest DPPH, ABTS and hydroxyl radical scavenging activity and ferrous ion chelating activity, which were 93.92%, 69.59%, 50.27% and 0.71, respectively. Four peptides were identified and screened by LC-MS/MS and the P1 (SWDNFFR) and P4 (WDWVGGR) showed high scavenging ability of DPPH free radical (70.23%-62.84%) and ABTS free radical (30.87%-60.54%). Molecular docking showed that P1 and P4 formed multiple hydrogen bonds with central residues of MPO.

Optimization of ultrasound-assisted extraction of fatty acids from royal jelly and its effect on the structural and antioxidant property

Fatty acids are the key active components in royal jelly (RJ) with various biological activities. In this study, a novel ultrasound-assisted extraction (UAE) method was established to extract fatty acids from RJ and their structural and antioxidant property were further evaluated. The optimum extraction conditions were as follows: liquid-to-solid ratio of 10:1, ultrasonic power of 450 W and ultrasonic duration of 20 min, resulting in a better extraction yield of 16.48 % and 10-hydroxy-2(E)-decenoic acid (10-HDA) content of 4.12 %. Furthermore, compared with the solvent extraction method, the antioxidant activity of extract by ultrasound was enhanced significantly by at least 448 %. GC-MS showed that ultrasound didn't change the chemical composition of fatty acids, while it significantly increased the content of fatty acids. SEM image illustrated that extracts by UAE showed a rougher, looser microstructure compared to the solvent method. Overall, UAE is a promising method to obtain fatty acids in RJ with high efficiency.

Characterization of Chilean hot spring-origin Staphylococcus sp. BSP3 produced exopolysaccharide as biological additive

A type of high molecular weight bioactive polymers called exopolysaccharides (EPS) are produced by thermophiles, the extremophilic microbes that thrive in acidic environmental conditions of hot springs with excessively warm temperatures. Over time, EPS became important as natural biotechnological additives because of their noncytotoxic, emulsifying, antioxidant, or immunostimulant activities. In this article, we unravelled a new EPS produced by Staphylococcus sp. BSP3 from an acidic (pH 6.03) San Pedro hot spring (38.1 °C) located in the central Andean mountains in Chile. Several physicochemical techniques were performed to characterize the EPS structure including Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Atomic Force Microscopy (AFM), High-Performance Liquid Chromatography (HPLC), Gel permeation chromatography (GPC), Fourier Transform Infrared Spectroscopy (FTIR), 1D Nuclear Magnetic Resonance (NMR), and Thermogravimetric analysis (TGA). It was confirmed that the amorphous surface of the BSP3 EPS, composed of rough pillar-like nanostructures, is evenly distributed. The main EPS monosaccharide constituents were mannose (72%), glucose (24%) and galactose (4%). Also, it is a medium molecular weight (43.7 kDa) heteropolysaccharide. NMR spectroscopy demonstrated the presence of a [→ 6)-⍺-D-Manp-(1 → 6)-⍺-D-Manp-(1 →] backbone 2-O substituted with 1-⍺-D-Manp. A high thermal stability of EPS (287 °C) was confirmed by TGA analysis. Emulsification, antioxidant, flocculation, water-holding (WHC), and oil-holding (OHC) capacities are   also studied for biotechnological industry applications. The results demonstrated that BSP3 EPS could be used as a biodegradable material for different purposes, like flocculation and natural additives in product formulation.

Effects of zinc oxide nanocomposites on microorganism growth and protection of physicochemical quality during maize storage

Maize moldy and spoilage due to microbial growth is a significant challenge in grain storage. This study aimed to evaluate the effectiveness of a zinc oxide nanocomposite, ZnO@mSiO2, prepared in our previous research, in inhibiting mold growth and preserving maize cell quality. The results demonstrated that ZnO@mSiO2 could effectively inhibit the growth of dominant microorganism, Aspergillus flavus, Talaromyces variabilis, Penicillium citrinum and Fusarium graminearum, in maize storage. Aspergillus flavus was selected as the model fungus, ZnO@mSiO2 effectively disrupted fungal hyphae structure, leading to reduced hyphal mass and inhibited spore germination. The inhibitory effect of ZnO@mSiO2 on mold growth was concentration-dependent. However, the ZnO@mSiO2 at an appropriate concentration (not exceeding 3.0 g/kg) preserved the integrity of maize cell membranes and enhancing the antioxidant activity within maize cells. The findings highlight the potential of ZnO@mSiO2 as an effective protectant to inhibit mold growth and preserve maize quality during storage.

Chemical compounds, antioxidant and scolicidal potencies of Thymus fontanesii essential oil

Medicinal plants have become a source of new drugs to treat various diseases due to their low cost, few side effects, and wide accessibility. Among these, essential oils are promising natural compounds for use in scolicidal activity. The targets of our current work were to assess the chemical composition, antioxidant and protoscolicidal activities of Thymus fontanesii essential oil. The essential oil was extracted by hydrodistillation, and chemical compounds were quantified by GC-MS/GC-FID. The in vitro antioxidant activity was determined by DPPH radical scavenging assay and ferric reducing power. Three concentrations of essential oil (4.625, 9.25, and 13.875 mg/ml) were tested for 5, 10, and 15 min against E. granulosus protoscoleces and their viability was assessed by eosin staining essay. The yield of the essential oil was 2.06 ± 0.41 % (w/w). Carvacrol (59.68 %) was the main compound of Thymus fontanesii essential oils. Moreover, Thymus fontanesii essential oil has an antioxidant activity IC50 of 346.08 μg/ml and EC50 of 869.82 μg/ml. Furthermore, 100 % mortality of protoscoleces was observed at the doses of 9.25 mg/ml and 13.875 mg/ml after 5 min of exposure. Our findings show a potency of antioxidant and protoscolicidal activities against protoscoleces of E. granulosus.

pH-responsive nanogels with enhanced antioxidant and antitumor activities on drug delivery and smart drug release

pH-responsive nanogels have played an increasingly momentous role in tumor treatment. The focus of this study is to design and develop pH-responsive benzimidazole-chitosan quaternary ammonium salt (BIMIXHAC) nanogels for the controlled release of doxorubicin hydrochloride (DOX) while enhancing its hydrophilicity. BIMIXHAC is crosslinked with carboxymethyl chitosan (CMC), hyaluronic acid sodium salt (HA), and sodium alginates (SA) using an ion crosslinking method. The chemical structure of chitosan derivatives was verified by 1H NMR and FT-IR techniques. Compared to hydroxypropyl trimethyl ammonium chloride chitosan (HACC)-based nanogels, BIMIXHAC-based nanogels exhibit better drug encapsulation efficiency and loading capacity (BIMIXHAC-D-HA 91.76 %, and 32.23 %), with pH-responsive release profiles and accelerated release in vitro. The series of nanogels formed by crosslinking with three different polyanionic crosslinkers have different particle size potentials and antioxidant properties. BIMIXHAC-HA, BIMIXHAC-SA and BIMIXHAC-CMC demonstrate favorable antioxidant capability. In addition, cytotoxicity tests showed that BIMIXHAC-based nanogels have high biocompatibility. BIMIXHAC-based nanogels exhibit preferable anticancer effects on MCF-7 and A549 cells. Furthermore, the BIMIXHAC-D-HA nanogel was 2.62 times less toxic than DOX to L929 cells. These results suggest that BIMIXHAC-based nanogels can serve as pH-responsive nanoplatforms for the delivery of anticancer drugs.

Effects of dietary thiamin (vitamin B1) on the growth performance, serum biochemical factors, immune response, and antioxidant activity of great sturgeon (Huso huso) juveniles

The present research evaluated the positive effects of dietary thiamin (vitamin B1) levels on the growth performance, serum biochemistry factors, immune response, and antioxidant activity of great sturgeon (Huso huso) juveniles. Thiamin was included in diets with levels of 0 (control, T0), 7 (T7), 15 (T15), and 25 (T25) mg/kg diet. Measurements of thiamin levels in diets indicated that they contained 1.80 (T0), 8.02 (T7), 16.2 (T15), and 26.6 (T25) mg thiamin/kg feed. Sturgeon juveniles (240 individuals) with average weight of 44.8 ± 1.96 g were distributed into 12 tanks, and fed with the experimental diets for 8 weeks. Final weight, body weight gain (%), specific growth rate, and feed conversion ratio (FCR) of great sturgeon were significantly influenced by dietary thiamin levels, and the maximum fish performance (P < 0.05) was obtained at a level of 15 mg/kg diet. The trypsin, chymotrypsin, creatine kinase, lipase, α-amylase, and alkaline phosphatase activities were notably (P < 0.05) affected by the dietary thiamin levels. The glucose content was not significantly (P > 0.05) different among the experimental treatments. Diets supplemented with thiamine increased significantly (P < 0.05) triglyceride, cholesterol, and total protein levels accompanied with significant (P < 0.05) decreases in aminotransferase aspartate and alanine aminotransferase activities. Serum antioxidant enzymes were remarkably (P < 0.05) higher, while serum malondialdehyde was significantly (P < 0.05) lower in the thiamin-treated fish compared with the control group. Total immunoglobulin, lysozyme, and ACH50 values were significantly (P < 0.05) higher in fish fed with thiamin-supplemented diets than in the control group. The results of the present study demonstrated that dietary thiamin have an important role in enhancing the growth performance, immune response, and antioxidant activity of great sturgeon. Based on the regression fitting curve of final weight, weight gain, specific growth rate, and FCR values, the optimal level of thiamin is found to be 15.0-17.5 mg/kg diet.

Pectic polysaccharides from Lilium brownii and Polygonatum odoratum exhibit significant antioxidant effects in vitro

Two pectic polysaccharides (WLBP-A3-c and WPOP-A-c) were isolated from traditional Chinese medicines Lilium brownii and Polygonatum odoratum, respectively. Monosaccharide composition, FT-IR, NMR and enzymatic analyses indicated that both WLBP-A3-c (59 kDa) and WPOP-A-c (33 kDa) contained homogalacturonan (HG), rhamnogalacturonan I (RG-I), and rhamnogalacturonan II (RG-II) domains, with mass ratios of 76.0: 17.2:6.8 and 76.8:10.6:12.6, respectively. Two RG-I domains WLBP-A3-c-DE1 and WPOP-A-c-DE1, correspondingly obtained from WLBP-A3-c and WPOP-A-c by enzymatic hydrolysis, were composed of repeating units of [→2)-α-L-Rhap-(1 → 4)-α-D-GalpA-(1→] with highly branched neutral sugar side chains at the O-4 position of Rhap, which contained arabinan, galactan, arabinogalactan I and II (AG-I and AG-II) side chains in different proportions. By comparison, WPOP-A-c exhibited higher scavenging effects against DPPH, ABTS and hydroxy radicals than WLBP-A3-c, probably because WPOP-A-c had higher contents of GalA residues and HG domains and lower molecular weight. Among three domains of WPOP-A-c, HG domain possessed the strongest activity in decreasing ROS production and promoting SOD activity, resulting in the effective protection of HepG2 cells against H2O2-induced oxidative stress. Our study provides evidence that pectins rich in HG domains from Lilium brownii and Polygonatum odoratum exhibit significant antioxidant effects, which hold potential for the application in the field of healthcare products.

Insight into the molecular mechanism underlying the enhancement of antioxidant activity in ovalbumin by high-energy electron beam irradiation

The effects of high-energy electron beam irradiation (HE-EBI) at various doses (0, 25, 50, 75, and 100 kGy) on the antioxidant activity of ovalbumin (OVA) were studied, and the molecular mechanism was investigated. The results showed that the antioxidant activity of HE-EBI-treated OVA was significantly enhanced in a dose-dependent manner. The irradiated OVA structure gradually unfolded to form a "honeycomb" structure, exposing the buried hydrophobic and free sulfhydryl groups inside the molecule. Two oxidation sites (M35 and T170), adjacent to the antioxidant peptide were identified by mass spectrometry, possibly exposing the antioxidant peptide through structural deconvolution. In addition, aspartic residues generated dicarbonyl compound under high-energy electron beam stress, and its accumulation further enhanced the antioxidant activity. Conclusively, HE-EBI can enhance the antioxidant activity of OVA through ionization effects, providing valuable information for the potential application of HE-EBI in the food industry.

Morphological, molecular identification and evaluation of antioxidant activity of seahorses from the Moroccan coasts

Seahorses, part of the small marine teleost fish family Syngnathidae, are increasingly under threat due to habitat degradation and overfishing. Notably used in traditional Chinese medicine, these fish have demonstrated significant pharmacological and cosmetic properties. In Morocco, however, seahorses are minimally exploited. This study aims to explore the biodiversity of Moroccan seahorses, focusing on identifying species from the Atlantic and Mediterranean coasts both morphologically and molecularly, and evaluating their antioxidant activity. The research involved collecting 62 dried seahorses from local fishermen. These specimens were subjected to detailed morphological and molecular identification through the DNA barcoding method, concentrating on the mitochondrial marker Cytochrome Oxidase I (COI) gene. Following DNA extraction and amplification, the sequences were analyzed for species identification and phylogenetic relationships. Additionally, the antioxidant activities of the seahorses were quantified using assays such as ABTS, reducing power, phosphomolybdenum, and β-carotene-linoleic acid. The combined morphological and molecular analyses consistently identified all specimens as Hippocampus hippocampus, and phylogenetic trees suggested a close relation with European and Turkish counterparts. Furthermore, the antioxidant assays revealed significant activity, with the ABTS assay showing an IC50 of 14.571 mg/mL ± 0.334, and the β-carotene-linoleic acid assay showing an IC50 of 1.273 mg/mL ± 0.166. The reducing power and phosphomolybdenum assays recorded EC50 values of 1.868 mg/mL ± 0.033 and 1.156 mg/mL ± 0.112, respectively. These results confirm the high antioxidant potential of Moroccan seahorses, suggesting their therapeutic value and necessitating measures for their biodiversity preservation at a national level.

Design, synthesis, In-vitro, In-silico and DFT studies of novel functionalized isoxazoles as antibacterial and antioxidant agents

A series of new isoxazolederivatives incorporating the sulfonate ester function has been synthesized from 2-benzylidenebenzofuran-3(2 H)-one, known as aurone. The synthesis of the target compounds was carried out following an efficient methodology that allows access to the desired products in a reproducible way and with good yield. The structures of the synthesized compounds were established using NMR (1H and 13C) spectroscopy and mass spectrometry. A theoretical study was performed to optimize the geometrical structures and to calculate the structural and electronic parameters of the synthesized compounds. The calculations were also carried out to understand the influence and the effect of substitutions on the chemical reactivity of the studied compounds. The synthesized isoxazoles were screened for their antioxidant and antibacterial activities. The findings demonstrate that the studied compounds exhibit good to moderate antibacterial activity against the tested bacteria (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli). Moreover, a number of the tested isoxazole derivatives exhibit high effectiveness against DPPH free radicals. Besides that, molecular docking studies were carried out to predict binding affinity and identify the most likely binding interactions between the active molecules and the target microorganisms' proteins. A 100 ns molecular dynamics study was then conducted to examine the dynamic behavior and stability of the highly potent isoxazole 4e in complex with the target bacterial proteins. Finally, the ADMET analyses suggest that all the synthesized isoxazoles have good pharmacokinetic profiles and non-toxicity and non-carcinogenicity in biological systems.

Preparation, characterization, antioxidant and antifungal activities of benzoic acid compounds grafted onto chitosan

The current study created three novel chitosan derivatives named BACS, PIBACS, and MHBACS by grafting benzoic acid (BA), p-isopropyl benzoic acid (PIBA), and m-hydroxybenzoic acid (MHBA) onto chitosan (CS). The structures of the derivatives were investigated using infrared spectroscopy (FT-IR) and nuclear magnetic resonance (13C NMR). The derivatives were discovered to be 45.06 %-60.49 % substituted using elemental analysis (EA). Based on the findings of in vitro antioxidant experiments (hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, and DPPH radical scavenging activity), all of the derivatives had a higher hydroxyl radical scavenging activity than the chitosan raw material. MHBACS scavenged (31.02 ± 0.90)% of hydroxyl radicals at 0.5 mg/mL, 28.69 % more than chitosan raw. The derivatives scavenged more superoxide anion radicals than the chitosan feedstock at a particular concentration. For instance, at a test dose of 0.2 mg/mL, the scavenging rate of MHBACS on superoxide anion radicals was 7.75 % greater than that of chitosan raw materials. DPPH radical scavenging activity, on the other hand, was not as competent as chitosan feedstock. The growth rate approach was used to assess the potential of the three derivatives to inhibit the development of four phytopathogenic fungi. Chitosan derivatives have better antifungal efficacy than chitosan raw materials. PIBACS, MHBACS, BACS, and Wuyiencin inhibited Phytophthora capsici by (98.03 ± 1.95)%, (81.73 ± 1.63)%, (66.38 ± 1.81)%, and (93.01 ± 2.69)%, respectively, at 1.0 mg/mL. PIBACS had a higher inhibitory impact on Phytophthora capsici than the positive control. Based on the evidence presented above, it is reasonable to conclude that the addition of benzoic acid molecules increased the antioxidant and antifungal capabilities of chitosan.

Tetraclinis articulata essential oil emulsion use as alternative to chemical fungicide to control tomato grey mould disease

Tetraclinis articulata essential oil proved to be effective in controlling tomato grey mould, so we would investigate its effect on some tomato defense mechanisms. The pretreatment of Botrytis cinerea infected tomato plants with TAEO emulsion enhanced the activity of antioxidant enzymes activity SOD, CAT, APX, and GPX, and total polyphenols content and it decreased IC50 of free radical-scavenging activity and H2O2 content. Results showed amelioration in antioxidant status in TAEO emulsion treated and B. cinerea infected plants indicating that treatment decreased infection in tomato plants. The qRT-PCR analysis of defense genes expression Chitinase SlChi, transcription factors SlWRKY and SlAP2/ERF, Lipoxygenase SlLOX, and Thioredoxin SlTRX showed that they were up-regulated as early as 12 hpi sustained with a second increase at 48 hpi in TAEO emulsion pretreated and infected plants. These results suggest the potential use of TAEO emulsion as natural product to induce tomato antioxidant status and activate defense genes.

Production of mulberry wine using selenium-enriched Saccharomyces cerevisiae: implications from sensory analysis, phytochemical and antioxidant activities

The present study aims to evaluate the quality of chemical, sensory properties and antioxidant potential of mulberry wine using selenium-enriched yeasts employing eight different methods (MW1-MW8). The selenium-enriched yeast significantly (p < 0.05) increased phytochemical profiles, flavor, quality and antioxidant capacity. The most effective method for raising the selenium level of mulberry wine was using L-seMC (MW5). Mulberry wine color was attributed to the anthocyanins and phytochemical composition with selenium content. DPPH and ABTS radical scavenging activity varied with change in treatment methods suggesting their impact on antioxidant activity. Total selenium content on L-SeMC supplementation proved a significant correlation between selenium content with total anthocyanin content, total polyphenol content and flavonoid content. Sensory analysis by electronic nose exhibited MW2 with high response value in the W2S sensor showing high alcohol concentration. GC-MS analysis showed the presence of 57 volatile aromatic compounds comprehended by esters and alcohol (isoamyl alcohol, 2-methylbutanol, 2,3-butanediol, and phenethyl alcohol). Principal component analysis affirms the response values for four categorical score values with reliability and consistency for all the parameters, significantly. Thus, the workflow demonstrates a simpler, cost-effective traditional methodology for rationalized outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05847-4.

Effect of C-phycocyanin purified from Spirulina platensis on cooled ram semen quality and in vivo fertility

This research sought to purify C-phycocyanin (C-PC) from Spirulina platensis and investigate its potential in enhancing the quality parameters and in vivo fertility of ram semen subjected to cooled storage at 5 °C, when using a skim milk (SM) based semen extender. The purification process of C-PC involved cold maceration, pre-purification using chitosan and activated charcoal, followed by purification through aqueous two-phase extraction (ATPE) and ion-exchange chromatography. Afterward, fifty ejaculates were collected from 4 fertile Boujaâd rams and extended using the SM extender at 37 °C, enriched with 0 μg/mL (control), 1.2 μg/mL, 2.4 μg/mL, 3.6 μg/mL, or 4.8 μg/mL of C-PC. The diluted semen was subsequently cooled to 5 °C using a controlled cooling process, with a gradual cooling rate of approximately 0.5 °C per minute, and its quality parameters were evaluated after 0, 4, 8, and 24 h of cooling storage. Then, its fertilization ability after 4 h of cooling storage was evaluated using artificial insemination. The adopted purification process yielded a grade analytical purity of 4.06. Additionally, semen extended in SM with a 2.4 μg/mL C-PC supplement displayed significant (P < 0.0001) enhancement in total motility, progressive motility, curvilinear velocity, straight-line velocity, average path velocity, viability and lipid peroxidation of ram semen at 0, 4, 8, and 24 h of cooling storage. These improvements were observed in direct comparison to both the control group and the other C-PC concentrations. Regarding fertility rates, semen extended in SM with a 2.4 μg/mL C-PC recorded a 76 % rate, a notable increment from the 63 % observed in ewes inseminated by semen extended in SM alone, although the difference was not statistically significant (p > 0.05). These findings underscore the promising potential of C-PC as a natural supplement for enhancing semen quality, warranting further investigations.

Enhancing the physicochemical stability and antioxidant activity of cape gooseberry calyx extract through nanoencapsulation in soy lecithin liposomes

The focus of this study was on the development, physicochemical characterisation and evaluation of the antioxidant activity of cape gooseberry calyx extract loaded into nanoliposomal systems. Various nanoliposomes were prepared and optimised using the ethanol injection method and characterised based on particle size, polydispersity and zeta potential measurements. Subsequently, the encapsulation efficiency and in vitro release profile of the natural antioxidant extract (NAE) were evaluated, and its antioxidant activity was assessed using the oxygen radical absorbance capacity assay. The results revealed that NAE-loaded nanoliposomes described desired quality features (e.g., particle size of < 200 nm, polydispersity index of < 0.3, zeta potential of > -40 mV and encapsulation efficiency of ∼70%). Furthermore, it was found that NAE release is controlled by various stages, and its antioxidant activity improves by around 30% when loaded into the nanoliposomes, suggesting that it could be a promising antioxidant functional raw material.

Evaluation of antihypertensive activity and molecular docking analysis of Padina boergesenii extract

INTRODUCTION

Antihypertensive drugs that are chemically synthesized usually tend to initiate different health complications. The quest for bioactive molecules to create novel medicines has focused on Marine resources like seaweeds. These molecules can furnish a positive probability for patients to gain benefits from these natural substances.

METHODS

This study aims to identify phytoconstituents present in brown seaweed-Padina boergesenii. Five different solvents were used to prepare extracts and their antioxidant activity as well as antihypertensive activity was evaluated. Phytoconstituents were identified using LC-MS/MS, and subjected to molecular interaction against ACE enzyme.

RESULTS

The 70% ethanolic extract exhibited the highest total phenolic content (TPC), significant radical scavenging activity and concentration dependent Angiotensin Converting Enzyme (ACE) inhibition activity. LC-MS/MS analysis confirmed the presence of bioactive compounds from which 7,8 dihydroxycoumarin had the highest affinity against ACE enzyme in molecular docking study.

CONCLUSION

These findings advocate that Padina boergesenii can be a potential source for developing novel antihypertensive therapeutic drug(s) and could pave the way for evolving effective and safe remedies from natural resources.

Biosynthesis of the phycocyanin β-subunit in Escherichia coli BL21 and its antioxidant activity and application in the preservation of fresh-cut apples

In this study, the biosynthesis of phycocyanin β-subunit (CpcB) in Escherichia coli BL21 was investigated, and its antioxidant activity and application in anti-browning of fresh-cut apples was explored. Four genes (cpcB, cpeS, hox1 and pcyA) involved in the biosynthesis of CpcB were cloned and transformed into E. coli BL21 by constructing recombinant plasmid pETDuet-5. The positive transformant was screened by ampicillin resistance. The analysis of SDS-PAGE and zinc fluorescence spectrum showed that CpcB was successfully expressed in E. coli BL21 with a molecular weight of 21 kDa. The purified CpcB had a maximum absorption peak at 615 nm, and its maximum florescence emission wavelength was 640 nm. It exhibited a stronger ability to scavenge four free radicals than Vc. The color change in fresh-cut apples was obviously delayed by the CpcB treatment. These results suggest that CpcB may be used as a potential anti-browning agent for food preservation.

Development of cassava starch-based films incorporated with phenolic compounds produced by an Amazonian fungus

Drug-release systems have attracted attention over the last few years since they can be used as a substitute for traditional methods of drug delivery. These have the advantage of being directly administered at the treatment site and can maintain the drug at adequate levels for a longer period, thus increasing their efficacy. Starch-based films are interesting candidates for use as matrices for drug release, especially due to starch's non-toxic properties and its biocompatibility. Endophytic fungi are an important source of bioactive molecules, including secondary metabolites such as phenolic compounds with antioxidant activity. In the present study, cassava starch-based films were developed to act as release systems of phenolic compounds with antioxidant activity. The Amazonian endophytic fungus Aspergillus niger MgF2 was cultivated in liquid media, and the fungal extract was obtained by liquid-liquid partition with ethyl acetate. The starch-based films incorporated with the fungal extract were characterized in regards to their physicochemical properties. The release kinetics of the extract from the film and its antioxidant and cytotoxic properties were also evaluated. The films incorporated with the extract presented maximum release after 25 min at 37 °C and pH 6.8. In addition, it was observed that the antioxidant compounds of the fungal extract maintain their activity after being released from the film, and were non-toxic. Therefore, considering the promising physicochemical properties of the extract-incorporated films, and their considerable antioxidant capacity, the films demonstrate great biotechnological potential with diverse applications in the pharmacological and cosmetic industries.

Chemical Profiling, in-vitro biological evaluation and molecular docking studies of Ruellia tweediana: An unexplored plant

Many Ruellia species have been utilized in traditional medicine and despite the prevalent use of Ruellia tweediana in folk medicine, its antioxidant potential and polyphenol content have not been investigated. Therefore, the present study aimed to explore the medicinal value of R. tweediana by evaluating its total phenolic (TPC) and flavonoid contents (TFC), GC-MS analysis, antioxidant, antibacterial, and enzyme inhibition activities. The TPC and TFC of the extract/fractions were assessed using the Folin-Ciocalteu and aluminum trichloride methods, respectively. To determine the antioxidant capacity, five different assays were used: DPPH, ABTS, CUPRAC, FRAP, and metal chelating assays. The inhibition activity against α-glucosidase, α-amylase, cholinesterases, and lipoxygenase enzymes was also analyzed. Furthermore, GC-MS was performed for chemical screening of non-polar fraction. The methanol extract showed the maximum TPC (167.34 ± 2.23 mg GAE/g) and TFC (120.43 ± 1.71 mg RE/g) values among all the tested samples. GC-MS screening of the n-hexane fraction showed the presence of 40 different phytoconstituents. The results demonstrated the highest scavenging potential of the methanol extract against DPPH (167.79 ± 2.75 mg TE/g) and ABTS (255.32 ± 2.91 mg TE/g) radicals, as well as the metal-reducing capacity measured by CUPRAC (321.34 ± 3.09 mg TE/g), FRAP (311.32 ± 2.91 mg TE/g), and metal chelating assay (246.78 ± 10.34 mg EDTAE/g). Notably, the n-hexane fraction revealed the highest α-glucosidase and α-amylase inhibition activity (186.8 ± 2.84 and 179.7 ± 4.32 mg ACAE/g, respectively) while methanol extract showed highest acetylcholinesterase and butyrylcholinesterase inhibition activity (198.6 ± 3.31 and 184.3 ± 2.92 mg GALE/g, respectively). The GC-MS identified Lupeol showed best binding affinity with all docked enzymes as compared to standard compounds. The presence of bioactive phytoconstituents showed by GC-MS underscores the medicinal importance of R. tweediana, making it a promising candidate for natural medicine.

Structural, rheological properties and antioxidant activities analysis of the exopolysaccharide produced by Rhizobium leguminosarum bv. viciae VF39

Microbial exopolysaccharide is an eco-friendly and non-toxic biopolymeric materials widely used in various industrial fields such as pharmaceutical, food and cosmetics based on its structural, rheological and physiochemical properties. A microbial exopolysaccharide (VF39-EPS) was directly isolated from Rhizobium leguminosarum bv. viciae VF39. Structural analysis using FTIR and 2D NMR spectroscopy confirmed the complete chemical structures of VF39-EPS as 3-hydroxybutanoylglycan with octasaccharide repeating units containing two pyruvyl, two acetyl, and one 3-hydroxybutanoyl group. VF39-EPS exhibited thermal stability up to 275 °C and showed characteristic rheological behaviors of structural fluid with weak gel-like properties above 4 % the aqueous solution, suggesting VF39-EPS as a potential effective thickener or hydrogel scaffolder. Flow behavior tests validated broad stability at a wide range of both pHs from 2 to 12 and temperatures from 25 to 75 °C, and even in the presence of various salts. Furthermore, VF39-EPS showed excellent antioxidant effects of 78.5 and 62.4 % (n = 3, p < 0.001) in DPPH scavenging activity and hydroxyl radical scavenging activity, respectively. Therefore, those structural, rheological and antioxidant properties suggest that VF39-EPS could be one of the excellent biomaterial candidates for cosmetic, food and pharmaceutical industries based on its characteristic rheological behaviors in various condition and excellent antioxidant activity.

Effect of high hydrostatic pressure treatment on the antioxidant activity of lactoferrin before and after gastrointestinal digestion

In this study, high hydrostatic pressure treatment of lactoferrin was used to investigate its effect on the hydrolysis and antioxidant activity of lactoferrin. The results showed that high hydrostatic pressure treatment at 600 MPa increased the exposure level of tryptophan residues of lactoferrin by 82.29%, which significantly altered the tertiary structure of lactoferrin, and this change was observed in scanning electron microscopy as an increase in the contact area of lactoferrin that could be contacted by proteases. Pressure treatments of 400 MPa and above increased the hydrolysis of lactoferrin for gastrointestinal digestion by 21.19%, which increased the release of antioxidant-related amino acids and increased the free radical scavenging capacity of lactoferrin intestinal digestive fluid by 35.12%. Meanwhile, two lactoferrin antioxidant peptides, QAYPNLCQLCK and NCPDKFCLFK, were identified in the lactoferrin intestine digest. These findings indicate that high hydrostatic pressure treatment could be a potentially beneficial method for processing lactoferrin.

Production of highly antioxidant lignin nanoparticles from a hardwood technical lignin

Eucalypt kraft lignin isolated in a LignoBoost™ pilot plant was characterized by GC-MS, ICP-OES, DSC, HPSEC, 31P NMR, and HSQC 2D-NMR to be used without any further processing to produce lignin nanoparticles (LNPs) by nanoprecipitation. Tetrahydrofuran (THF) was used as a solvent, and water as a non-solvent. Microscopic analysis (TEM) showed that LNPs were regularly spherical with some hollow particles dispersed in-between, and sizes were tunable by changing the solvent dripping rate onto the non-solvent. LNP particle sizes had a bimodal distribution, with the largest population having an average apparent hydrodynamic diameter ranging from 105.6 to 75.6 nm. Colloidal dispersions of LNPs in water presented good stability in different dilutions without significant size changes upon storage at pH close to neutral for as long as 45 days. Zeta potentials around -40 mV were obtained for LNP suspensions at pH ranging from 7 to 9. The high carbohydrate content (circa 10 % on a dry basis, mostly xylans) of the lignin precursor did not interfere in LNP formation, whose antioxidant activity was expressive as demonstrated by the ABTS assay at pH 7.4, with an EC50 of 4.04 μg mL-1. Also, the Trolox® equivalent antioxidant capacity (TEAC) of LNPs reached 1.90 after 40 min reaction time.

Chitosan/aloe vera gel coatings infused with orange peel essential oils for fruits preservation

Continuous fruit waste poses significant environmental and economic challenges, necessitating innovative fruit coating technologies. This research focuses on harnessing discarded orange peels to extract essential oil (OPEO), which is then integrated into a chitosan/aloe vera (CTS/AVG) matrix. The study comprehensively characterised the coating in terms of its physicochemical properties, antioxidant capacity, and antimicrobial efficacy. The investigation involved an analysis of particle size and distribution in the coating solutions, highlighting changes induced by the incorporation of orange peel essential oil (1 %, 2 % and 3 % v/w) into the chitosan/aloe vera (4:1 v/v) matrix, including particle size reduction and enhanced Brownian motion. The study quantifies a 33.21 % decrease in water vapour transmission rate and a reduction in diffusion coefficient from 9.26 × 10-11 m2/s to 6.20 × 10-11 m2/s following the addition of OPEO to CTS/AVG. Assessment of antioxidant potential employing DPPH radical scavenging assays, revealed that CTS/AVG/3 %OPEO exhibited notably superior radical scavenging activity compared to CTS/AVG, CTS/AVG/1 %OPEO, and CTS/AVG/2 %OPEO, demonstrated by its IC50 value of 17.01 ± 0.45 mg/mL. The study employs the well diffusion method, demonstrating a higher susceptibility of gram-negative bacteria to the coating solutions than gram-positive counterparts. Remarkably, CTS/AVG/3 %OPEO displayed the most pronounced inhibition against Escherichia coli, generating an inhibitory zone diameter of 14 ± 0.8 mm. The results collectively emphasised the potential of CTS/AVG/3 %OPEO as a viable natural alternative to synthetic preservatives within the fruit industry, attributed to its exceptional antioxidant and antimicrobial properties.

Exploring the antimalarial and antioxidant efficacy of transition metal(II) chelates of thiosemicarbazone ligands: spectral investigations, molecular docking, DFT, MESP and ADMET

Malaria, a relentless and ancient adversary, continues to cast its shadow over vast swathes of the globe, afflicting millions of people and have a heavy toll on human health and well-being. Despite substantial progress in the fight against this parasitic disease in recent decades, malaria still persists as a substantial global health concern, especially in some specific region which have limited resources and vulnerable populations. Thus, to ascertain an combating agent for malaria and its associated dysfunction, 4-(4-ethylphenyl)-3-thiosemicarbazide and benzaldehydes based two new thiosemicarbazone ligands (1-2) and their cobalt(II), nickel(II), copper(II), zinc(II) metal complexes (3-10) were synthesized in the present research work. The synthesized compounds were comprehensive characterized through spectral and physical investigations, demonstrating octahedral stereochemistry of the complexes. Further, the antimalarial and antioxidant potential of the compounds (1-10) were analyzed by micro assay and DPPH assay protocols, respectively, to examine the therapeutic aspect of the compounds. The performed biological evaluations revealed that the complexes are more efficient in controlling infectious ailment in comparison of ligands. The complexes (5), (6), (10) shows significant efficiency for malarial and oxidant dysfunctions whereas Zn(II) complex (6) exhibit highest potency with 1.02 ± 0.07 and 2.28 ± 0.05 µM IC50 value. Furthermore, to support the highest antimalarial potency of the (3-6) complexes and their associated ligand (1), the computational studies like molecular docking, DFT, MESP and ADMET analysis were executed which were supported the biological efficacy of the complex (6) by providing numerous parameters like binding interaction electronegativity, electrophilicity, HOMO value and electron density.

Characterization and bioactivities of coffee husks extract encapsulated with polyvinylpyrrolidone

Coffee processing generates large amounts of residues of which a portion still has bioactive properties due to their richness in phenolic compounds. This study aimed to obtain a coffee husks extract (CHE) and to encapsulate it (ECHE) with polyvinylpyrrolidone using a one-step procedure of solid dispersion. The extraction and encapsulation yields were 9.1% and 92%, respectively. Thermal analyses revealed that the encapsulation increased the thermal stability of CHE and dynamic light scattering analyses showed a bimodal distribution of size with 81% of the ECHE particles measuring approximately 711 nm. Trigonelline and caffeine were the main alkaloids and quercetin the main phenolic compound in CHE, and the encapsulation tripled quercetin extraction. The total phenolics content and the antioxidant activity of ECHE, assayed with three different procedures, were higher than those of CHE. The antioxidant activity and the bioaccessibility of the phenolic compounds of ECHE were also higher than those of CHE following simulated gastrointestinal digestion (SGID). Both CHE and ECHE were not toxic against Alliumcepa cells and showed similar capacities for inhibiting the pancreatic α-amylase in vitro. After SGID, however, ECHE became a 1.9-times stronger inhibitor of the α-amylase activity in vitro (IC50 = 8.5 mg/mL) when compared to CHE. Kinetic analysis revealed a non-competitive mechanism of inhibition and in silico docking simulation suggests that quercetin could be contributing significantly to the inhibitory action of both ECHE and CHE. In addition, ECHE (400 mg/kg) was able to delay by 50% the increases of blood glucose in vivo after oral administration of starch to rats. This finding shows that ECHE may be a candidate ingredient in dietary supplements used as an adjuvant for the treatment of diabetes.

Recent advances on the preparation conditions, structural characteristics, physicochemical properties, functional properties and potential applications of dialdehyde starch: A review

Starch, a natural storage polysaccharide of plant kingdom, has many industrial applications. However, native starch has some inherent shortages, which can be overcome by structural modification. Dialdehyde starch, one kind of oxidized starch produced by periodate oxidation, has good physical properties and bioactivities with wide applications in different fields. Dialdehyde starch is typically achieved by oxidizing native starch slurry through periodate oxidation under controlled reaction conditions. Several factors including the source of starch, the type of oxidant, the molar ratio of oxidant to starch, reaction temperature, reaction time and solution pH value can influence the synthesis of dialdehyde starch. Dialdehyde starch shows different spectroscopic/chromatographic characters and physicochemical properties from native starch. Moreover, dialdehyde starch exhibits good antioxidant activity, antimicrobial activity and cross-linking property. Based on these functional properties, dialdehyde starch has shown application potentials in food packaging, thermoplastic production, enzyme immobilization, heavy metal ion adsorption, drug delivery, wood adhesion and leather tanning. In this review, the preparation conditions, structural characteristics, physicochemical properties, functional properties and potential applications of dialdehyde starch are summarized for the first time. The future research and development prospects of dialdehyde starch are also discussed.

Synthesis of Hydrazide Derivative of Betulinic Acid, Its Organometallic Complexes, Characterization and Bioassay

Betulinic acid and its derivatives comprehend an immense prospective toward the development of cytotoxic, antiviral, antimicrobial and antioxidant agents. Cisplatin (cytotoxic drug) divert the attentions to develop organometallic compounds with pronounced biological activities. The current study was aimed for the first time to synthesize, characterize and evaluate biologically a series of metal (Fe, Cu, Zn, Sn and Sb) complexes of betulinic acid hydrazide. First step involved the formation of hydrazide derivative of betulinic acid (ligand) by modification at C-28 carboxylic acid moiety of betulinic acid with hydrazine followed by the synthesis of its metal complexes using salts of different metals (Fe, Cu, Zn, Sn and Sb). Physical state, melting point, Fourier-transform infrared (FT-IR) and 1 H nuclear magnetic resonance (1 H-NMR) spectral techniques were used to characterized the ligand and its metal complexes. Agar well diffusion method and agar tube dilution assay were performed to evaluate its antibacterial and antifungal activities respectively. DPPH assay was carried out to develop antioxidant properties by the reported methods.

Development of gelatinized-core liposomes for the oral delivery of EGCG with improved stability, release property, and cellular antioxidant activity

Epigallocatechin gallate (EGCG) exhibits antioxidant, anti-cancer, and anti-inflammatory properties; however, low cellular permeability and stability limit its bioavailability. Liposomes have the potential for enhancing bioactive compounds' bioavailability. Yet, low entrapment efficiency (EE) and burst release of hydrophilic substances make them impractical for food industry use. Here, we incorporated gelatin into liposomes to overcome these limitations. EGCG-loaded conventional liposomes (EGCG/CLs) and gelatinized-core liposomes (EGCG/GLs) had small particle sizes and high absolute zeta potentials. Encapsulation in EGCG/GLs significantly improved the EE of EGCG compared to that in EGCG/CLs (p < 0.05). EGCG/GLs retained EGCG in the hydrophilic region, whereas EGCG/CLs exhibited significantly higher release of EGCG during storage (p < 0.05). Additionally, in comparison to EGCG/CLs, gelatin incorporation significantly enhanced the sustained release, cellular permeability, and cellular antioxidant activity of EGCG (p < 0.05). This study emphasizes the capability of gelatinized-core liposomes as a potent delivery system for enhancing the stability and bioavailability of EGCG/CLs, broadening the prospects for utilizing them in the food industry.

Induction of antioxidant activities of Arthrospira platensis and Chlorella vulgaris by modified culture conditions

Microalgae are considered a promising source for obtaining natural compounds with strong antioxidant activity. Despite the great progress made in this field, there is still need for further studies applying simple and cost-effective modifications to reveal their full potential and enhance antioxidant properties. Arthrospira platensis and Chlorella vulgaris are some of the most common cells studied for this purpose. In this study, it was aimed to develop a bioprocess for the enhancement of antioxidant properties of these two microalgae by evaluating the effect of different culture conditions. With this aim, the impacts of light intensity/reactive oxygen species and nitrogen sources/reactive oxygen species were evaluated for the A. platensis and C. vulgaris cells, respectively. Results showed that the antioxidant potential of A. platensis was found to be correlated with the phycocyanin and total phenolic content of cells, and 80 µmol photons m-2 s-1 light intensity induced antioxidant activity in a two-step cultivation mode. For C. vulgaris cells, maximum antioxidant activities of 68.10 ± 1.51% and 75.68 ± 0.66% were obtained in cultures with NH4Cl (0.016% (w/v)) for DPPH and ABTS assays, respectively. The applied oxidative stress factors exhibited different effects on the antioxidant activities of the cells because of their cellular morphologies and changing mechanisms of reactive oxygen species. These outcomes show the potential of applied modifications on cells and suggest a promising route to enhance antioxidant activities of microalgae for further research.

Structural and functional investigation on stem and peel polysaccharides from different varieties of pitaya

Varieties of plant species may affect the composition and structures of the polysaccharides, thus have an impact on their chemical properties and biological activities. Herein, the present study comparatively evaluated the differences in the chemical composition, morphological structures, antioxidant activity, and anti-inflammatory activity of the stem and peel polysaccharides from different varieties of pitaya. The FT-IR and NMR spectra indicated that the six polysaccharides had similar structural features, whereas the physicochemical characterization showed that they differed significantly in terms of the monosaccharide composition, molecular weight, and surface morphology. In addition, different varieties of pitaya polysaccharides exhibited different antioxidant activities and similar anti-inflammatory activities. These data suggested that varietal differences resulted in pitaya stem and peel polysaccharides with different monosaccharide compositions and molecular weights, thus led to different antioxidant activities and protection against oxidative damage, while similar structural features were closely related to their similar anti-inflammatory activities. Therefore, the study of the stem and peel polysaccharides from different varieties of pitaya can help us to better understand the relationship between their composition and structure and their biological activities. In addition, pitaya stem and peel polysaccharides have the potential to act as antioxidants or to treat inflammatory damage.