Source Of Natural Antioxidants Research Articles

Phytochemical analysis by LC MS/ MS and in vitro antioxidant activity of the Algerian endemic plant Dianthus sylvestris subsp. aristidis (Batt.) Greuter & Burdet

<p>The present work aimed to carry out the phytochemical analysis and antioxidant activity of hydro-methanolic, ethyl acetate and butanolic extracts of Dianthus sylvestris subsp, aristidis (Batt,) Greuter & Burdet leaves. Phenolics, flavonoids and flavonols contents were measured by the Folin-Ciocalteu reagent and the aluminum chloride (AlCl3) method respectively. Phytochemical analysis was determined by using LC-ESI-MS/MS method. Antioxidant activity, in vitro, was evaluated by six different assays including: DPPH scavenging, ABTS cation radical, Ferrous ions chelating, Phenanthroline, Reducing power and Silver nanoparticle. The findings showed that the butanolic extract was found to be higher in phenolics and flavonoids contents (121.45 ± 1.87 μg GAE/mg extract and 57.09±0.14 μg QE/mg extract respectively). While ethyl acetate extract was found to be higher in falvonols contents (41.90±0.98µg QE/mg extract). The LC-ESI-MS/MS analysis of ethyl acetate and butanolic extracts revealed the presence of fifteen compounds among which: four phenolic acids, five flavonoids, one phenolic aldehyde and three vitamins, with P- coumaric acid, Hesperetin, Vanillin, Ascorbic Acid as major compounds respectively. The butanolic and ethyl acetate extracts exhibited the highest antioxidant activity in Phenanthroline assay (A0,5: 17.75± 0.72 µg/mL and A0.5: 21.02 ± 0.43 µg/mL respectively). On the basis of the significant findings, D. sylvestris subsp, aristidis would be recommended as a new potential source of natural antioxidant for pharmaceutical industries.</p>

Natural chemicals for healthy living: plant secondary metabolic compounds

Free radicals are produced by a variety of normal biological processes including aerobic metabolism and pathogenic defense mechanisms. They can also be a result of external exposures such as radiation, pollutants, and cigarette smoke. Reactive oxygen species, or ROS, are a subset of free radicals that contain oxygen. A diet high in antioxidants may reduce the risk of many diseases (including heart disease and certain cancers). Antioxidants scavenge free radicals from the body cells and prevent or reduce the damage caused by oxidation. The protective effect of antioxidants continues to be studied around the world. During aerobic metabolism, oxidants, or reactive oxygen species, are created in our bodies, which can cause a number of illnesses, including cancer and cardiovascular conditions. The substances that balance these oxidants called antioxidants. Natural antioxidants are recommended over synthetic antioxidants, which have been discovered to have adverse effects. Natural antioxidants are the secondary metabolites of phytochemicals. The impact of oxidants on human health and how natural antioxidants counteract them have both been reviewed. The main plant sources of natural antioxidants, several methods for recovering antioxidants from plant matrices, and the superiority of indirect supercritical fluid extraction over other methods are all discussed.

Structural modification of poppy-pollen protein as a natural antioxidant, emulsifier and carrier in spray-drying of O/W-emulsion: Physicochemical and oxidative stabilization

This study was aimed to investigate the efficiency of poppy-pollen (PP) protein and peptides as carrier for spray-drying encapsulation of grape-seed oil (GSO). The composition of amino acids, functional properties and bioactivity (scavenging of DPPH, ABTS, OH, and nitric-oxide radicals, reducing power, total antioxidant, TBARS levels in O/W-emulsion, and chelation of Fe2+ and Cu2+ ions) of PP-protein were affected by the enzymolysis time. Partial enzymolysis (30 min) led to improved solubility, protein surface activity and increased physical stability of GSO/W emulsion (relative to creaming, aggregation and flocculation) during storage. Also, spray-dried emulsions with this type of carrier (H−30) had the highest production yield (~67 %), solubility (~92 %), flowability, encapsulation efficiency (~96 %), reconstitution ability (least size and EE changes), physical and oxidative stability. The evaluation of the chemical structures (FTIR) indicated the formation of hydrogen bonds between the cis-alkene groups of fatty acids and the hydroxyl groups of the amide A and B regions, as well as the trapping of oil in the carrier matrix. SEM images illustrated the effect of native protein carriers (particles with smooth, dents, and hollow surfaces with surface pores), partially (wrinkled and reservoir-type), and strongly (irregular structures, sticky and amorphous agglomerates) hydrolyzed peptides on the morphology of oily-particles. The results of this research indicate the usability of partially hydrolyzed poppy-pollen protein as a source of natural antioxidant, emulsifier, and carrier in the production, stabilization, and encapsulation of oxidation-sensitive bioactive components and emulsions.

Antioxidant, Antibacterial Activities and Cytotoxicity of Garlic Leaf Extract from Garlic Waste

Five garlic parts (root, clove skin, leaf, flower stalk and garlic peel) of garlic waste from garlic harvest processing were used in this study. Each part of the garlic waste was screened for total phenolic, flavonoid and antioxidant activity after extraction with 70% ethanol. Interestingly, garlic leaf (GLf) showed the greatest richness of total phenolic, flavonoid and antioxidant activity. GLf was selected to extract with water and 70% ethanol and the highest extraction yield was achieved with water extract. The GLf extracts demonstrated a good quality standard of physical and chemical properties. The aqueous extract of GLf revealed the highest total phenolic content of 1,676.40 ± 18.02 mg GAE/100 g extract. Both aqueous and ethanolic extracts did not differ regarding total flavonoid contents, showing values of 118.60 ± 6.10 mg QUE/100 g extract and 110.90 ± 2.30 mg QUE/100 g extract, respectively. Phenolic compounds including gallic acid, catechin and tannic acid were detected in the aqueous and ethanolic extracts of GLf by HPLC assay. Moreover, four flavonoid compounds including isoquercetin, quercetin, kaempferol and rutin were detected in aqueous extract whereas the ethanolic extract presented apigenin, isoquercetin, quercetin and kaempferol. The ethanolic extract of GLf demonstrated the stronger antioxidant activity than aqueous extract. GLf extracts also exhibited antimicrobial activity against pathogenic bacteria with MIC and MBC values of 125-250 mg/mL. In addition, GLf aqueous extract showed lower toxicity on Vero cells than ethanolic extract. Therefore, GLf waste can be used as a cheap source of natural compounds and antioxidants, with potential applications in different biological, medicinal and food products. Keywords: Allium sativum L., Antibacteria, Antioxidant, Garlic, Toxicity

Methoxylated Flavonols and ent-Kaurane Diterpenes from the South African Helichrysum rutilans and Their Cosmetic Potential.

Chromatographic fractionation of a methanol extract of Helichrysum rutilans afforded seven known compounds. The isolated compounds were identified as 5,7,8-trihydroxy-3,6-dimethoxyflavone-8-O-2-methyl-2-butanoate (C-1), 5,7-dihydroxy-3,6,8-trimethoxyflavone (C-2), 5-hydroxy-3,6,7,8-tetramethoxyflavone (C-3), 5-hydroxy-3,6,7-trimethoxyflavone (C-4), ent-kaurenoic acid (C-5), ent-kauran-18-al (C-6), and 15-α-hydroxy-(-)-ent-kaur-16-en-19-oic acid (C-7). Compounds C-1-C-4 demonstrated high antioxidant capacities on ORAC hydroxyl radical (2.114 ± 4.01; 2.413 ± 6.20; 1.924 ± 16.40; 1.917 ± 3.91) × 106; ORAC peroxyl radical (3.523 ± 3.22; 2.935 ± 0.13; 2.431 ± 8.63; 2.814 ± 5.20) × 103 µMTE/g; and FRAP (1251.45 ± 4.18; 1402.62 ± 5.77) µMAAE/g, respectively. Moderate inhibitory activities against Fe2+-induced lipid peroxidation were observed for C-1-C-4 as IC50 values of 13.123 ± 0.34, 16.421 ± 0.92, 11.64 ± 1.72, 14.90 ± 0.06 µg/mL, respectively, while their respective anti-tyrosinase activities with IC50 values of 25.735 ± 9.62, 24.062 ± 0.61, 39.03 ± 13.12, 37.67 ± 0.98 µg/mL were also observed. All compounds demonstrated TEAC values within the range of 1105-1424 µMTE/g. The result is an indication that a methanol extract of H. rutilans might possibly be a good source of natural antioxidants against ailments caused by cellular oxidative stress and as inhibitors against skin depigmentation, as well as possible raw materials needed for slowing down perishable agricultural products. This is the first report on the phytochemical and biological evaluation of H. rutilans.

Preparation of a new resource food-arabinogalactan and its protective effect against enterotoxicity in IEC-6 cells by inhibiting endoplasmic reticulum stress

Plant polysaccharides can be used as bioactive natural polymers that provide health benefits, however high molecular weight neutral polysaccharides have not shown good bioactivity. In this study, high molecular weight neutral arabinogalactan was isolated and structurally characterized to investigate it antioxidant activity against IEC-6 cells. In this study, a neutral polysaccharide (AG-40-I-II) was obtained from the roots of Larix gmelinii (Rupr.) Kuzen. and purified using ethanol fractional precipitation and purification on a DEAE-52 cellulose column and a Superose 12 gel filtration column. The structural characteristics of AG-40-I-II was detected by chemical and spectroscopic methods. The results showed that the average molecular weight of AG-40-I-II was 18.6 kDa, the main chain was composed of →4)-β-D-Gal-(1, → 4, 6)-β-D-Gal-(1 and →4)-β- D-Glc-(1, the side chain is composed of T-β-L-Araf(1 → 6). The effect of AG-40-I-II on H2O2-induced IEC-6 cell injury was determined by MTT method. Besides, AG-40-I-II could reduce the level of MDA and increase SOD activity on IEC-6 cells, which could significantly inhibit the production of ROS. Importantly, AG-40-I-II inhibited the splicing of XBP1 by IRE1α through the ERS pathway and reduced the cell apoptosis induced by H2O2. In summary, the results of this study indicate that AG-40-I-II, as a natural source of plant polysaccharides, has good antioxidant activity, and is expected to become a safe plant source of natural antioxidants, which has great potential in biomedicine potential.

Antioxidant Activity Of Kintamani Siamese Orange Peel Extract (<em>Citrus Nobilis</em>) With Different Polar Solvent: An In Vitro Experimental Study

Siamese oranges (Citrus nobilis) are one of Bali's most widely developed citrus fruits, especially in the Kintamani area. Siamese oranges (Citrus nobilis) contain many secondary metabolite compounds as a source of natural antioxidants. In this study, secondary metabolite compounds in plants were obtained through the extraction method. In addition to the extraction method, selecting the type of solvent is one of the main factors affecting the extraction results. Polar solvents tend to produce higher antioxidant activity, which aimed to determine the best polar solvent in producing Kintamani Siamese orange extract peel (Citrus nobilis) with the highest antioxidant activity. The research method used was experiment, where the orange peel was extracted through maceration using three polar solvents: methanol; ethanol; and water. Furthermore, antioxidant activity testing was carried out using the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hidrate) method. Data from the analysis of antioxidants in IC50 was compared and classified according to BIOS Classification. The results showed that methanol solvent produced yield and antioxidant activity with the highest IC50. Methanol solvent as a polar solvent could produce Kintamani Siamese orange peel extract (Citrus nobilis) with moderate antioxidant activity according to BIOS classification. Further research is needed to explore other potentials benefit of Kintamani Siamese orange peel waste (Citrus nobilis) as an application of zero waste system.

СРАВНИТЕЛЬНАЯ ОЦЕНКА АНТИОКСИДАНТНОЙ АКТИВНОСТИ ТРАВЫ И КОРНЕЙ ЦИКОРИЯ ОБЫКНОВЕННОГО, ПРОИЗРАСТАЮЩЕГО НА ТЕРРИТОРИИ ОРЕНБУРГСКОЙ ОБЛАСТИ

The purpose of the work: to study the effect of water extracts of herb and roots of Cichorium intybus L., growing in the Orenburg region, on the processes of free radical oxidation in in vitro systems. Materials and methods. The objects of the study were samples of C. intybus L. raw materials collected in 2020 in the Adamovsky, Belyaevsky, Buzuluksky and Tulgansky districts of the Orenburg region. The antioxidant activity of aqueous extracts from raw materials was determined by the method of registration of chemiluminescence on the device "Chemiluminomer KhLM-003" in systems simulating the processes of production of reactive oxygen species in the Central Research Laboratory of the Federal State Budgetary Educational Institution of Higher Education "Bashkir State Medical University" of the Ministry of Health of the Russian Federation . Statistica 10.0 for Windows (StatSoft, Inc.) was used for statistical processing. Results. The analysis of the obtained results established that the samples of the roots of C. intybus L. growing in the Adamovsky district of the Orenburg region, as well as all the studied samples of the herb of C. intybus L., have antioxidant properties. It was found that the most pronounced antioxidant activity, expressed in the inhibitory effect of extracts from raw materials samples on chemiluminescence in model systems, is shown by the herb of C. intybus L., growing in the Buzuluksky district of the Orenburg region, and the roots of C. intybus L., collected in the Adamovsky district of the Orenburg region. Conclusion. The herb of of Cichorium intybus L., growing in the Orenburg region, and the roots of Cichorium intybus L., collected in the Adamovsky district, can be considered as potential promising sources of natural antioxidants of plant origin.

Phytochemical status and antioxidant capacity of selected hot pepper varieties cultivated in Tanzania

Hot pepper is one of the most important economic fruits with abundant of nutritional qualities. Thus, the consumption of foods of plant origin with high nutritional and bioactive compounds of high antioxidants capacity is a major concern nowadays. A study was conducted to determine and quantify concentrations of important bioactive compounds present in the nine selected hot pepper varieties cultivated in Tanzania. Hot peppers were grown in the field at Botany department research farm, University of Dar es Salaam from March to September, 2021. Then, ripe-fruit extracts were used to determine vitamin C, beta-carotene, lycopene, total phenolic content (TPC) and total flavonoid content (TFC)among the varieties quantitatively. The results indicated that there were very high significant variations on the nutrients and bioactive compound concentrations (p<0.0001) among all varieties of hot pepper evaluated. The highest amount of vitamin C was 948.30 ± 22.6 mg/100g recorded from orange bird eye variety. The high concentration of beta-carotene was 0.62 ± 0.006mg/ 100 ml recorded from orange bird eye. The highest concentration of lycopene was 0.55 ± 0.0003 mg/ 100 ml from Big red cayenne. The highest concentration of TPC was 454.247 ± 20.9mg GAE/ 100g obtained from Big red cayenne. The highest concentration of TFC was 8.92 ± 0.15 mg RE/ 100g obtained from Big red cayenne. High variability was observed among the hot pepper varieties; Big red cayenne variety with the highest concentrations of TPC, TFC and lycopene, showed to have the highest radical scavenging capacity. Big red cayenne can be a cheap source of natural antioxidants, therefore recommended for future development of nutraceuticals or healthy food products and conveying great benefits for food and pharmaceutical industries, consumers, and producers.

LC‐MS based metabolite profiling, in‐vitro antioxidant and in‐vivo antihyperlipidemic activity of Nigella sativa extract

AbstractThe aim of this study was to identify the bioactive phytoconstituents present in the aqueous extract of Nigella sativa and also, to evaluate the antioxidant and antihyperlipidemic activity in Wistar rats. The LC‐MS/MS analysis was assessed for the determination of different bioactive compounds present in N. sativa extract. Total phenolic and flavonoid content were determined by using validated Folin‐Ciocalteu and Aluminum chloride colorimetric methods, respectively. The in‐vitro antioxidant and in‐vivo antihyperlipidemic activity in Wistar rats were also evaluated. Preliminary phytochemical screening of the extract showed the presence of alkaloids, flavonoids, phenols, glycosides, and amino acids in the aqueous extract. The bioactive compounds of the aqueous extract were identified through LC‐MS/MS analysis. The in‐vitro antioxidant activity of N. sativa showed the highest free radical scavenging capacity in DPPH, H2O2, and OH radical scavenging assays with IC50 values 11.916 ± 2.828, 30.294 ± 13.790, and 12.048 ± 2.828 µg/mL, respectively. Evaluation of antihyperlipidemic activity of extract in Wistar rats showed that a high dose (800 mg/kg) of extract significantly decreased total cholesterol (TC) 71.76 ± 6.91 mg/dL, TG 83.6 ± 8.09 mg/dL, low‐density lipoproteins (LDL‐c) 33.86 ± 6.05 mg/dL, very low‐density lipoproteins (VLDL‐c) 16.72 ± 1.61 mg/dL level in blood. However, the HDL‐C level was significantly improved (21.18 ± 1.80 mg/dL) as compared to HFD‐induced control rats (11.76 ± 1.14 mg/dL) after 28 days of treatment. Also, at the same dose, animal body weight was also decreased to 162.6 ± 16.40 g compared with control 184.4 ± 10.24 g. The aqueous extract of N. sativa was found to be an effective natural source of antioxidant and hypolipidemic agents. This activity was attributed to the presence of diverse bioactive compounds in it.

Glomus fasciculatum an arbuscular mycorrhizal fungus alleviate the adverse effects of lead, arsenic, nickel, and improves growth parameters of Monarda citriodora Cerv.ex Lag (lemon beebalm)

Heavy metals induce negative impacts on plants, however, the symbiotic association of an arbuscular mycorrhizal fungi (AMF) Glomus fasciculatum offers an effective tolerance response. The aim of the present study was to investigate the impact of Lead (Pb), Arsenic (As), and Nickel (Ni) with and without the application of AMF on one of the important medicinal and aromatic plants Monarda citriodora Cerv. ex Lag (lemon beebalm). The metal concentrations mixed in soil were: Pb (25 and 50 mg/kg), As (15 and 30 mg/kg) and Ni (20 and 40 mg/kg) along with constant dose of AMF (2.7 g/kg soil) while untreated plants were taken for comparison. Results showed that higher concentrations of Pb (50 mg/kg), As (30 mg/kg), and Ni (40 mg/kg) decreased the plant height by 48%, 6%, and 7% respectively, and the number of branches by 19%, 10%, and 25% respectively when compared with controls. The biomass and nutrient contents were also altered in the plants that received Pb, As, and Ni. However, the application of AMF has improved the overall growth and development of plants but not more than the control. Furthermore, higher concentrations of Pb (50 mg/kg), As (30 mg/kg), and Ni (40 mg/kg) increased total phenolics by 975%, 375%, and 373% respectively, flavonoids by 149%, 136%, and 127% respectively, proline content by 656%, 225%, and 472% respectively, and radical scavenging activity by 124%, 146%, and 157% respectively, when compared with control. Additionally, higher concentrations of Pb, As, and Ni treatments also decreased the AMF colonization rate in roots by 37%, 35%, and 49% when compared with their lower concentrations. The elevation of secondary metabolites and scavenging activity in response to metal toxicity indicates that M. citriodora is a rich source of natural antioxidants. So, future strategies are required to study valuable antioxidant compounds present in this plant.

Phytochemical Analysis and Antioxidant Activity of Juglans Regia L.

Free radicals are the primary cause of the majority of degenerative diseases. The substances that collect free radicals are antioxidants. The main intent of current research was to make an inquiry into the phyto-chemical & in-vitro anti-oxidant profile of fruit husk of Juglans regia extract. The technique used to put to the test the antioxidant abilities of extracts included the DPPH assay, superoxide radical scavenging, ferric thiocyanate (FTC], and hydroxyl radical scavenging assay. Preliminary phytochemical analysis was screened using standard methods. Phytochemical investigation found that it contains carbohydrates, alkaloids, terpenoids, tannins, flavonoids, glycosides and saponins. Methanolic extract of Juglans regia showed better antioxidant capability than ethyl acetate extract. According to the results of this study, Juglans regia fruit husks may be a reliable source of natural antioxidants.

Comparative Analysis of Chemical Composition of Zanthoxylum myriacanthum Branches and Leaves by GC-MS and UPLC-Q-Orbitrap HRMS, and Evaluation of Their Antioxidant Activities.

Zanthoxylum myriacanthum Wall. ex Hook. f., a plant belonging to the Rutaceae family and the Zanthoxylum genus, is extensively utilized for its medicinal properties and as a culinary seasoning in China and Southeast Asian countries. However, the chemical composition and biological activities of Z. myriacanthum branches and leaves remain insufficiently explored. In this study, the volatile and non-volatile components of Z. myriacanthum branches and leaves were analyzed using GC-MS and UPLC-Q-Orbitrap HRMS techniques. A total of 78 volatile compounds and 66 non-volatile compounds were identified. The volatile compounds were predominantly terpenoids and aliphatic compounds, while the non-volatile compounds were primarily flavonoids and alkaloids. The branches contained 52 volatile compounds and 33 non-volatile compounds, whereas the leaves contained 48 volatile compounds and 40 non-volatile compounds. The antioxidant activities of the methanol extracts from Z. myriacanthum branches and leaves were evaluated using ABTS and DPPH free-radical-scavenging assays, both of which demonstrated certain antioxidant activity. The methanol extract of leaves demonstrated significantly higher antioxidant activity compared to that of the branches, possibly due to the higher presence of flavonoids and phenols in the leaves, with IC50 values of 7.12 ± 0.257 μg/mL and 1.22 × 102 ± 5.01 μg/mL for ABTS and DPPH, respectively. These findings enhance our understanding of the chemical composition and antioxidant potential of Z. myriacanthum. The plant holds promise as a natural source of antioxidants for applications in pharmaceuticals, cosmetics, and functional foods. Further research can explore its broader biological activities and potential applications.

A Subacute Toxicity Test of Rhizophora apiculata Stem Bark Ethanol Extract on the Number, Motility, and Morphology of Male Rattus Norvegicus Spermatozoa

Indonesia has the largest mangrove ecosystem in the world. Rhizophora apiculata is a mangrove often used as traditional medicine by Indonesians. It has previously been researched that the ethanol extract of Rhizophora apiculata stem bark has benefits as a source of natural antioxidants. However, there has yet to be much research on the toxicity of this extract. Therefore, researchers want to know the subacute toxic dose of Rhizophora apiculata bark extract on fertility parameters. The type of research is experimental research with a completely randomized research design. The sample consisted of 30 male rats, which were divided into 5 groups, namely the control group, which received no treatment, and the P1-P4 treatment group, which was given Rhizophora apiculata bark extract every day with 4 dose levels starting from 114 mg/kg BW to a dose of 912 mg/kg BW for 28 days. On day 30, the rats were euthanized, and the fertility parameters of the rat spermatozoa were examined using a microscope. Kruskal-Wallis analysis and One-Way ANOVA showed p<0.05 for the spermatozoa's number, motility, and morphology. The toxic dose that can reduce the number of spermatozoa is found at 912 mg/kg BW; the toxic dose that reduces spermatozoa motility is 228 mg/kg BW; and the toxic dose that affects spermatozoa morphology is 456 mg/kg BW. This research concludes that the subacute toxic dose of the ethanol extract of Rhizophora apiculata stem bark against the spermatozoa of the male Rattus norvegicus Sprague Dawley strain in the subchronic toxicity test was 228 mg/kg BW.

The Potential of Underutilized Plant Resources and Agricultural Wastes for Enhancing Biodiesel Stability: The Role of Phenolic-Rich Natural Antioxidants

Growing concerns about energy security and environmental sustainability have fueled demand for sustainable and renewable energy sources in recent years. Biodiesel, a renewable alternative to conventional fuels, has gained significant attention as a potential source of energy. However, the stability of biodiesel during storage and its susceptibility to oxidation remain major challenges. To address these issues, researchers have turned their focus to the utilization of natural antioxidants. Studies on sources of natural antioxidants, particularly those made from waste, such as food, have been extensively conducted. However, there are still some restrictions, such as inconsistency in quality, the development of microbes, and difficulties with regulations, all of which have an impact on sustainability and the phenolic contents. Phenolic compounds are known for their excellent antioxidant properties and ability to inhibit the oxidation process. The review provides an overview of various underutilized plant resources and agricultural wastes that are rich in phenolic contents and demonstrate higher antioxidant activities, such as Vitex doniana, Uapaca kirkiana, Parinari curatellifolia, Tamarindus indica L, fruit peels, and crop residues. It discusses the extraction methods employed to obtain phenolic antioxidants from these sources and highlights their antioxidant activities. Additionally, the review examines the effects of phenolic antioxidants on key parameters, including induction period, peroxide value, acid value, and viscosity. The review concluded by highlighting the potential of underutilized plant resources and agricultural wastes as sustainable sources of phenolic-rich natural antioxidants for enhancing biodiesel stability. According to the literatures, phenolic antioxidants present in underutilized plant resources and agricultural wastes can chelate metal ions, scavenge free radicals, and break oxidation chain reactions, thereby preventing the degradation of biodiesel. Moreover, the limitation of the use of natural antioxidants in the stabilization of biodiesel like instability at high temperatures has been highlighted.

Evaluation of in vitro enzyme inhibitory, anti-inflammatory, antioxidant, and antibacterial activities of Oldenlandia corymbosa L. and Oldenlandia umbellata L. whole plant extracts

BackgroundOldenlandia corymbosa and Oldenlandia umbellata are well-known medicinal plants in various traditional systems of medicine and used to treat bronchitis, asthma, tuberculosis, constipation, and leprosy. We evaluated the phytochemical content, antioxidant potential, enzyme inhibitory action, anti-inflammatory, and antibacterial activities of the whole plant extracts of O. corymbosa and O. umbellata due to their therapeutic importance. MethodsThe phytochemical analysis includes qualitative analysis and quantification of total phenolics, flavonoids, tannins, flavonols, proanthocyanidins, and vitamin E. Enzyme inhibitory assays were studied using α-amylase and α-glucosidase enzymes and anti-inflammatory activity was determined by egg albumin denaturation assay. Antioxidant potential was estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethyl benzothiozoline-6-sulfonic acid) diammonium salt (ABTS), ferric reducing antioxidant power (FRAP), hydroxyl radical, superoxide, nitric oxide, metal chelating, and phosphomolybdenum assays. Minimum inhibitory concentrations of extracts were studied against ten bacterial strains by the microdilution method. ResultsThe aqueous extract of O.umbellata showed a higher extract yield (5.0%). The highest amount of total phenolics and flavonoids were observed in the ethanolic extract of O.umbellata (77.23±0.46 mg GAE/g) and O.corymbosa (19.01±0.26 mg GAE/g). Ethanolic extract of O.umbellata (IC50 of 31.71±0.32 µg/mL) and aqueous extract of O.corymbosa (30.53±1.83 µg/mL) showed notable α-amylase inhibitory effect and petroleum ether extract of both plants observed good inhibition against α-glucosidase enzyme. Likewise, petroleum ether extract of O.umbellata (IC50 of 57.16±1.88 µg/mL) showed a moderate anti-inflammatory effect. In all extracts, considerable antioxidant potential was recorded specially with aqueous extract in the nitric oxide scavenging assay with an IC50 of 40.72±1.25 µg/mL. Ethanolic extract of O.umbellata and petroleum ether extract of O.corymbosa (MIC of 56.25 µg/mL) showed good antibiotic potency in lower concentrations which proves these two valuable herb's potential in herbal preparations. ConclusionsThe results of the study provide a basis for further studies aiming to evaluate the possibilities of using the O. umbellata and O. corymbosa as natural sources of antioxidants, enzyme inhibitory, and antibacterial agents. Further studies could be directed to exploit these plants in experimental animal models as potential pharmaceutical agents.

Rapid Screening of Microalgae as Potential Sources of Natural Antioxidants.

In order to rapidly screen microalgae species as feedstocks for antioxidants, extracts were obtained from 16 microalgae strains (under 11 genera, 7 classes) using two methods: a one-step extraction with ethanol/water and a three-step fractionating procedure using hexane, ethylacetate, and water successively. Measuring the total phenol content (TPC), total carotenoid content (TCC), and antioxidant activity of the extracts, indicating TPC and TCC, played an important role in determining the antioxidant activity of the microalgae. A weighted scoring system was used to evaluate the antioxidant activity, and the scores of microalgal samples from two extraction methods were calculated using the same system. Among the investigated microalgae, Euglena gracilis SCSIO-46781 had the highest antioxidant score, contributing to high TPC and TCC, followed by Arthrospira platensis SCSIO-44012, Nannochloropsis sp. SCSIO-45224, Phaeodactylum tricornutum SCSIO-45120, and Nannochloropsis sp. SCSIO-45006, respectively. Additionally, the above-mentioned five strains are currently being applied in commercial production, indicating this system could be effective not only for screening microalgal antioxidants, but also for screening microalgal species/strains with strong adaptation to environmental stress, which is a critical trait for their commercial cultivation.

Optimizing extraction conditions and isolation of bound phenolic compounds from corn silk (Stigma maydis) and their antioxidant effects.

During the processing of maize, Stigma maydis, also known as corn silk, is normally discarded as waste. Phytochemical research was carried out on the S. maydis to use it as a valuable source of bioactive components. This research aimed to maximize the recovery of free and bound phenolic compounds from corn silk under optimal experimental conditions. Response surface design was operated to optimize the alkaline hydrolysis extraction of bound phytochemicals from corn silk based on total phenolic content and DPPH radical scavenging activity. The optimum conditions (i.e., NaOH concentration 2M, digestion time 135min, digestion temperature of 37.5°C, the solid-to-solvent ratio of 1:17.5, and acetone) were obtained. The optimum parameters were used to extract the corn silk. The structures of two compounds isolated from ethyl acetate extracts were then identified as friedelin (1) and (E)-4-(4-hydroxy-3-methoxyphenyl) but-3-en-2-one (2). The DPPH, H2 O2 , and ABTS % inhibition of the compounds is as follows: compound (1) 74.81%, 76.8%, 70.33% and compound (2) 70.37%, 56.70% and 57.46%, respectively. The current study has opened previously unexplored perspectives of the composition of bound compounds in corn silk and established the foundations for more effective processing and utilization of corn waste. PRACTICAL APPLICATION: Bound phenolic compounds from corn silk under optimal experimental conditions were obtained. Corn silk can be utilized as a type of medicinal herb as well as a source of inexpensive natural antioxidants.

ANTIOXIDANT AND ANTIDIABETIC ACTIVITY OF DECALEPIS HAMILTONII LEAVES EXTRACT

In most nations, diabetes mellitus is a serious and rising health issue. The goal of the study was to compare the antidiabetic effects of leaves extracts of Decalepis hamiltonii in normal and diabetic rats induced with alloxan. Using 120 mg/kg of alloxan monohydrate, diabetes was induced. In order to considerably lower blood glucose levels in both normal and alloxan-induced diabetic rats, D. hamiltonii methanolic extract was given at doses of 200 mg and 400 mg, along with glibenclamide at a dose of 7 mg/kg bwt. Additionally, the injection of the extract dramatically reduced the levels of AST, ALT, triglycerides, and total blood cholesterol while simultaneously raising the amount of liver glycogen. In order to perform the oral glucose tolerance test (OGTT), separate groups were given doses of D. hamiltonii methanolic extract (200 mg, 400 mg), and glibenclamide (7.5 mg), which effectively reduced blood sugar levels following an oral glucose load at all time points. These findings indicate that diabetic rats' blood glucose levels were successfully lowered by the methanolic extract of D. hamiltonii leaves. The antioxidant potential of the leaves was measured using various in vitro assays. The methanolic extracts showed high antioxidant activity measured as scavenging of DPPH, superoxide and hydroxyl radicals. The antioxidant activity did not correlate with the phenolic content of the extracts. These results demonstrate the antioxidant potency of the leaves extracts which could be the basis for its alleged health promoting potential of D. hamiltonii. The leaves of D. hamiltonii could serve as a new source of natural antioxidants or nutraceuticals with potential applications to reducing the level of oxidative stress and related health benefits. KEYWORDS: Decalepis hamiltonii, Antidiabetic, Antioxidant, Alloxan, AST, OGTT

Fermentative extraction of phenolic compounds from unripe areca nuts by solid‐state fermentation using newly isolated Rhizopus orizaeMW538932

SummaryAreca nut (pericarp of Areca catechu L.) is a rich source of valuable phenolic compounds. Presence of a psychoactive agent, Arecoline, pose a challenge in the use of areca nut extracts. With an aim to maximise the extraction of phenolic compounds, a newly isolated Rhizopus orizae MW538932, was employed for the solid‐state fermentation of unripe areca nut (6–7 months' maturity) powder. Supplementary nutrients (carbon and nitrogen sources) for the media and the solvents for the extraction of phenolic compounds from the fermented medium were optimised. The optimised process could produce an extract having a total phenolic content of 186.03 ± 2.50 mg gallic acid equivalent and total flavonoid content of 139.70 ± 2.00 mg catechin equivalent per gram of the sample. UHPLC–MS/MS studies and HPLC analysis showed the presence of plethora of phenolic compounds and the absence of Arecoline and other alkaloids. This flavonoid‐rich extract can be a potential source of natural antioxidants for food and pharmaceutical industry.