Orthogonal Test Design for Optimization of the Extraction of Polysaccharides from Inonotus cuticularis and Their Antioxidant Activities

Medical fungi polysaccharides belong to a very important species of biological macromolecules, which are the basic substances that effectively maintain and ensure the normal operation of biological life activities. However, research on extraction and biological activity of Inonotus cuticularis polysaccharides has never been reported. In this study, the optimum yield of Inonotus cuticularis polysaccharides was determined by the orthogonal experimental design. The highest yield of 3.10±0.06 % was obtained with extraction temperature of 80 °C, extraction time of 150 min, and water to raw material ratio of 30 mL/g and repeated twice. After deproteinization for 5 times, the protein removal rate reached 70.10±1.75 %, and the content of polysaccharides and protein were 46.64 and 0.42 %. Infrared spectrometer indicated that Inonotus cuticularis polysaccharides are typical β‐pyranose with characteristic peaks of polysaccharides. Subsequently, the activities of scavenging free radicals for the deproteinated polysaccharides were studied. When the concentration of Inonotus cuticularis polysaccharides was 0.3 mg/mL, the scavenging activities of the sample on DPPH^., ^.OH, ABTS^.+ and O₂^.? reached 83.67±0.27, 65.21±4.82, 43.45±1.36 and 80.28±2.30 %, respectively, and the reducing power reached 0.46±0.01. The IC₅₀ values scavenging DPPH^., ^.OH, ABTS^.+ and O₂^.? were 0.139±0.13, 0.162±0.14, 0.317±0.30 and 0.121±0.10 mg/mL, respectively. Results showed that Inonotus cuticularis polysaccharides present potential stronger antioxidant activities, especially ^.OH scavenging activity and reducing power. Experimental results could provide research basis of Inonotus cuticularis polysaccharides for further exploitation and utilization.     

Chemical Characterization,Antioxidant Capacity and Antimicrobial Potential of Essential Oil from the Leaves of Baccharis oreophila Malme

This is the first time that composition, antimicrobial potential and antioxidant ability of essential oil from the leaves of Baccharis oreophila are reported. Essential oil was obtained by hydrodistillation and analyzed by GC/MS. Antimicrobial potential was evaluated by diffusion disk and broth microdilution methods. ABTS^.+, DPPH^. and FRAP methods were employed for antioxidant activity evaluation. Essential oil yield was 0.47 %. Sixty‐five compounds were identified, representing 88.53 % of the total essential oil, which showed to be rich in oxygenated (37.88 %) and hydrocarbons sesquiterpenes (34.84 %). The main constituents were khusimone (16.37 %) and spathulenol (16.12 %). Antimicrobial activity was verified against S. aureus (10.33±0.5 mm, MIC: 1250 μg mL^?1) and C. albicans (8.66±0.5 mm, MIC: >2500 μg mL^.1). Antioxidant ability was evidenced by FRAP (4.09 μmol FeSO₄ E mL^?1), ABTS^.+ (1.45 μmol TE mL^?1) and DPPH^. (1.04 μmol TE mL^?1) scavenging capacity. Results showed that this essential oil has interesting biological potential, encouraging further investigations especially in relation to action mechanisms of antimicrobial and antioxidant activity.     

Variations in the Components and Antioxidant and Tyrosinase Inhibitory Activities of Styphnolobium japonicum (L.) Schott Extract during Flower Maturity Stages

Styphnolobium japonicum (L.) S chott is widely cultivated in China, and its flowers and flower buds (FFB‐SJ) are commonly used as traditional Chinese medicine. This work aimed to assess variations in the chemical components and antioxidant and tyrosinase inhibitory activities of S. japonicum extract during five flower maturity stages (ES1–ES5). The results showed that the contents of total flavonoids, rutin, and narcissin were highest at ES1, whereas the contents of quercetin and isorhamnetin were highest at ES3. ES1 presented considerable antioxidant activities in terms of reducing power (RP) and 1,1‐diphenyl‐2‐picrylhydrazyl radical (DPPH^.) and hydroxyl radical (^.OH) scavenging capacity, whereas ES3 showed excellent tyrosinase inhibitory activity and 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical (ABTS^.+)‐ and O₂^.?‐scavenging capacity. Rutin and quercetin are the main bioactive components of FFB‐SJ with antioxidant and tyrosinase inhibition, and the immature flower buds of S. japonicum (S2 and S3) with excellent biological activities and relatively high extract yields were the best for product development.     

In vitro Biological Activities of Seed Essential Oils from the Cameroonian Spices Afrostyrax lepidophyllus Mildbr. and Scorodophloeus zenkeri Harms Rich in Sulfur‐Containing Compounds

The chemical composition of the essential oils obtained from the seeds of bush onion (Afrostyrax lepidophyllus) and tropical garlic tree (Scorodophloeus zenkeri), plants used as spices in the traditional African cuisine, was determined by GC‐FID and GC/MS analyses. Moreover, in vitro biological properties of the oils, namely, the cytotoxic, antioxidant, and antimicrobial activities, were investigated by the MTT, the DPPH^. and ABTS^.+ scavenging, and the agar disc‐diffusion methods, respectively. Both oils were composed mainly by S‐containing compounds, accounting for 91.0–96.1% of the total oil compositions, which provided them the typical garlic‐ and onion‐like odors of spices. The predominant compound in both oils, 2,4,5,7‐tetrathiaoctane ( 1 ; 51.5–52.9%), was isolated by preparative TLC and structurally elucidated by ¹H‐ and ¹³C‐NMR data. The oils exhibited a strong inhibitory effect on the growth of human cancer cells, namely, T98G (human glioblastoma multiforme cell line), MDA‐MB 231 (human breast adenocarcinoma cell line), A375 (human malignant melanoma cell line), and HCT116 (human colon carcinoma cell line) cells, and a good DPPH^.‐ and ABTS^.+‐scavenging activity, while the antimicrobial effects were negligible. The volatile compositions of A. lepidophyllus and S. zenkeri oils supported their use as odorous spices. The significant inhibition activities detected make these oils worthy of further investigation as promising chemopreventive agents to be exploited in the African pharmaceutical market.     

A Comprehensive Search of the Primary and Secondary Metabolites and Radical Scavenging Potential of Trillium govanianum Wall. ex D. Don

Trillium govanianum rhizomes are traditionally consumed as a raw powder and decoction for the treatment of health complications. Hence, the present study aimed to investigate whether aqueous and alcoholic extracts of T. govanianum rhizomes under hot and cold extraction conditions have similar or dissimilar chemical, nutrient, and antioxidant profiles. The total phenolics, flavonoids, carbohydrates, proteins, fats, and energy values were estimated in all the conditionally prepared samples. The total phenolics (21.23±1.4 mg GAE/g extract), flavonoids (70.57±3.24 mg RE/g extract) were found higher in hot ethanolic extract (TGHEt), while cold water extract (TGGC) showed higher nutrients including amino acids (10.545±0.219 mg/g) and nucleosides (1.803±0.018 mg/g). The nutrient energy value (2.60 and 2.49 Kcal/g extract) was higher in cold and hot ethanolic extracts. Further, TGHEt scavenged the DPPH^. (IC₅₀; 870±22 μg/mL) and ABTS^.+ (IC₅₀; 80±1.49 μg/mL) effectively and proved its highest antioxidant activity compared to other samples. In LC/MS/MS-based metabolite profiling, twenty-six metabolites (fatty acids, steroidal saponins, triterpene saponins, ecdysteroid hormones) were confirmed with mass fragmentation and literature, while one hundred nine metabolites were identified using the METLIN database. The principal component analysis showed clustering of hot condition extracts while cold extracts were differentially located in quadrants. The heatmaps exhibited the associations and differences between metabolite composition, solvents, and extraction conditions. The identified metabolites speculatively predicted the biosynthesis pathway of T. govanianum. Findings also illustrated that T. govanianum is a source of bioactive nutritional components and saponins. The current metabolite profiling of T. govanianum will help in its agricultural and biotechnological interventions for higher quality produce.     

Effect of Seasonal and Regional Variations on Phenolic Compounds of Deverra scoparia (Flowers/Seeds) Methanolic Extract and the Evaluation of Its in Vitro Antioxidant Activity

The widespread use of Deverra scoparia Coss. & Durieu in Algerian folk‐medicine as a remedy can be relatively attributed to its total phenolic compounds. The current study aimed to provide a scientific basis for optimal collection and usage of Deverra scoparia Coss. & Durieu plant. Hence, 37 samples were gathered from nine sites in Algeria during two seasons 2016 and 2017, then exposed to a green extraction. Total phenolic (TPC), flavonoid (FC) and condensed tannins (CTC) content were estimated spectrophotometrically. The antioxidant activity was measured using five different methods, DPPH^., ABTS^.+, FRAP, CUPRAC and Fe²⁺‐chelating. The results have revealed considerable amounts of TPC varied from 804 to 1544 mg GAE/100 g dry matter, FC started from 187 up to 410 mg QE/100 g dry matter and CTC varied from 111 to 394 mg CE/100 g dry matter. The best IC₅₀ values (μg/mL) of DPPH^., ABTS^?+, FRAP, CUPRAC and Fe²⁺‐chelating tests were 56.62, 5.41, 21.26, 52.93 and 78.10, respectively. Moreover, high correlations were found between CTC and most of the antioxidant tests. Hence, CTC are suggested to be the principal group of antioxidant activity in Deverra scoparia Coss. & Durieu extracts.     

Evaluation of Antioxidant,Antibacterial and Enhancement of Antibiotic Action by Punica granatum Leaves Crude Extract and Enriched Fraction against Multidrug-Resistant Bacteria

The aim of this study was to evaluate the phytochemical composition, antioxidant, and antimicrobial potential of crude extract and fractions of Punica granatum leaves. The extract was produced by turbo extraction, after which hexanic, ethyl acetate, and aqueous fractions were obtained by partitioning. The chemical analyses were performed by thin layer chromatography and high-performance liquid chromatography, and the antioxidant activities were assayed by DPPH^. and ABTS^.+. Minimal inhibitory and bactericidal concentrations (MIC/MBC) were applied to twenty-two bacteria. Most strains susceptible to extract/fractions and resistant to antibiotics were selected, and ampicillin, azithromycin, ciprofloxacin, and gentamicin were associated with the ethyl acetate fraction (EAF) against multidrug-resistant strains in modulatory and checkboard models. The data from chromatographic analyses showed flavonoids and tannins in the extract, as well as the enrichment of EAF in phenols, mainly flavonoids. The flavonoids were connected to the electron transfer activity demonstrated in the DPPH^. and ABTS^.+ assays. Gram-positive strains are more susceptible to EAF. The subinhibitory concentrations of P. granatum enhanced the antimicrobial activity of the agents and reduced the EAF individual MIC, and the combination of EAF and antibiotics demonstrated a synergistic effect. These results present a promising approach for developing a therapy in which antioxidant extracts and fractions can be used in combination with antibiotics.     

Chemical Variability and Antioxidant Activity of Limbarda crithmoides L. Essential Oil from Corsica

The chemical compositions of 25 Corsican Limbarda crithmoides ssp. longifolia essential oils were investigated for the first time using GC‐FID, GC/MS, and NMR analyses. Altogether, 65 compounds were identified, accounting for 90.0–99.3% of the total oil compositions. The main components were p‐cymene ( 1 ; 15.1–34.6%), 3‐methoxy‐p‐cymenene ( 4 ; 11.8–28.5%), 2,5‐dimethoxy‐p‐cymenene ( 5 ; 5.9–16.4%), thymol methyl ether ( 6 ; 1.3–14.9%), α‐phellandrene ( 2 ; 0.9–11.9%), and α‐pinene ( 3 ; 0.2–13.4%). The chemical variability of the Corsican oil samples was studied using multivariate statistical analysis, which allowed the discrimination of two main clusters. A direct correlation between the water salinities of the plant locations and the chemical compositions of the L. crithmoides essential oils was evidenced. Indeed, essential oils rich in 1 (30.4–34.6%) were found in samples growing in the wetlands of the southern oriental coast, which exhibit high salinity levels (24.4±0.2–33.9±0.2 ppt), and essential oils with lower contents of 1 (15.1–27.3%) were isolated form samples growing in the wetlands of northern Corsica, which exhibit lower salinity levels (10.90±0.20–15.47±0.15 ppt). The antioxidant potential of L. crithmoides essential oil was also investigated, by assessing the DPPH^.‐ and ABTS^.+‐scavenging activities and the reducing power of ferric ions, and was found to be interesting. Moreover, using bioassay‐guided fractionation of the essential oil, a higher antioxidant activity was obtained for the oxygenated fraction and both ester and alcohol subfractions.     

Caffeoylquinic Acids,Cytotoxic, Antioxidant,Acetylcholinesterase and Tyrosinase Enzyme Inhibitory Activities of Six Inula Species from Bulgaria

Chlorogenic (5‐CQA), 1,5‐, 3,5‐, 4,5‐ and 3,4‐dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus‐christi L., I. bifrons L., I. aschersoniana Janka var. aschersoniana, I. ensifolia L., I. conyza (Griess .) DC. and I. germanica L. by HPLC analysis. The amount of 5‐CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5‐DCQA (4.05–55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5‐DCQA, 4,5‐DCQA and 3,4‐DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92±0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41±0.55 %). I. bifrons extract was found to be the most active sample against ABTS^.+ (TEAC 0.257±0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 μg/mL toward non‐cancer (MDCK II) and cancer (A 549) cells.     

The antioxidant properties of polypore mushroom <Emphasis Type="Italic">Daedaleopsis confragosa</Emphasis>

Daedaleopsis confragosa belong to a large and remarkable group of mushrooms called polypores. This type of mushroom could be easily said to be quite unexplored and unused when it comes to its antioxidant properties. Thus, in order to evaluate its antioxidant activity, the investigation had to include the total phenolics and flavonoide content, the content of Selenium, the content of Zinc, the scavenging capacity on DPPH^· and OH^· radicals, reducing power and capacity to remove lipid peroxidation. The investigated mushroom extract contained 54.17 mg GAE/g of total phenols and 48.46 mg CE/g of total flavonoides. Zinc and Selenium were detected and quantified by using inductively coupled plasma mass spectroscopy. The scavenging activity of the radicals was found to exhibit 50% of the inhibition value (IC₅₀ value) at the extract concentration of 0.015±0.007 mg/ml for the investigated D. confragosa extract. By using electron paramagnetic resonant spectroscopy it was found that the investigated extract does not have a significant role in the prevention of lipid peroxidation. It was effective in scavenging on ^·OH radical, RI was 56±2%.     

Variability in the Phytochemical Contents and Free Radical‐Scavenging Capacity of Capsicum annuum var. glabriusculum (Wild Piquin Chili)

The variability in the phytochemical concentrations of Capsicum annuum var. glabriusculum has not been extensively analyzed among wild populations and ecologic niches in its phylogeographic area. This study aimed to determine the variations in the phytochemical and antioxidant contents of the wild Piquin chili. The total flavonoid content of hydroalcoholic extracts (0.06 to 0.70 mg equivalent of quercetin per gram of dry weight (mg QE/g DW)), free radical‐scavenging capacity for 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH^.) radicals (0.55 to 8.55 mm TE/g DW), amount of 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS⁺) in aqueous extracts (18.13 to 107.6 mm TE/g DW) and pungency (21,760 to 88,476 Scoville heat units) were highly variable. By analyzing the spatial distribution using the first three principal components, correlations between the phytochemical content and the free radical‐scavenging capacity (in both extracts) and flavonoid and phenolic contents (in the hydroalcoholic extract) were observed. Consistent with the statistical analysis, the spatial analysis showed intraregional differences in composition patterns, with an emphasis on central and coastal areas. Flavonoid contents, polyphenol contents and free radical‐scavenging activity were the phytochemical components that mainly contributed to the diversity of the population.     

Optimization of growing conditions for pigments production from microalga Navicula incerta using response surface methodology and its antioxidant capacity

Navicula incerta is a marine microalga distributed in Baja California, México, commonly used in aquaculture nutrition, and has been extended to human food, biomedical, and pharmaceutical industries due to its high biological activity. Therefore, the study aimed to optimize culture conditions to produce antioxidant pigments. A central composite experimental design and response surface methodology (RSM) was employed to analyze the best culture conditions. The medium (nitrogen-deficient concentrations), salinity (PSU = Practical Salinity Unity [g/kg]), age of culture (days), and solvent extraction (ethanol, methanol, and acetone) were the factors used for the experiment. Chlorophyll a (Chl a) and total carotenoids (T-Car), determined spectroscopically, were used as the response variables. The antioxidant capacity was evaluated by DPPH^? and ABTS^?+ radical inhibition, FRAP, and anti-hemolytic activity. According to the overlay plots, the optimum growth conditions for Chl a and T-Car production were the following conditions: medium = 0.44 mol·L^-1 of NaNO₃, salinity = 40 PSU, age of culture: 3.5 days, and solvent = methanol. The pigment extracts obtained in these optimized conditions had high antioxidant activity in ABTS^?+ (86.2–92.1% of inhibition) and anti-hemolytic activity (81.8–96.7% of hemolysis inhibition). Low inhibition (33–35%) was observed in DPPH^?. The highest value of FRAP (766.03 ± 16.62 μmol TE/g) was observed in the acetonic extract. The results demonstrated that RSM could obtain an extract with high antioxidant capacity with potential applications in the biomedical and pharmaceutical industry, which encourages the use of natural resources for chemoprevention of chronic-degenerative pathologies.     

Influence of Morphological Variability and Habitat on the Chemical Composition of Essential Oils of an Algerian Endemic Origanum Species (Origanum floribundum Munby)

The genus Origanum L. (Lamiaceae) enjoys a socioeconomic interest and constitutes one of the most popular spices. In the literature, the study of this taxon is limited mainly to the chemical composition, antimicrobial, antifungal, and antioxidant activities of the essential oils. In Algeria, few works have been done in this area, including the endemic and rare species: Origanum floribundum Munby . In this study, our contribution highlights the influence of the ecological parameters and of the variation of morphological traits on the chemical composition and the antioxidant activity of the essential oils of six populations. The major oils constituents are carvacrol, γ‐terpinene, and p‐cymene with carvacrol predominance (31.8 – 60.8%) in over five populations (MS1 – MS4 and MS6). However, the population of Ain Terraeur (MS5) of which individuals present a foliar polymorphism, distinguishes itself by p‐cymene predominance (42.6%). This would denote a new chemotype and/or variety which seem well differentiated on the dendrogram of the Ascending Hierarchical Classification (A.H.C) and its foliar morphology. The antioxidant activity of the six samples evaluated by the scavenging activity of free radicals DPPH^? and ABTS^?+ showed a potent efficiency for the sample with foliar polymorphism population (IC₅₀ = 51.6 ± 0.31 and 12.71 ± 0.37 μg/ml, respectively).     

Phenolic production and antioxidant properties of some Macedonian medicinal plants

Investigations have been made to study the production of phenolic compounds (total phenolics, flavonoids and phenylpropanoids) and total antioxidant capacity in 27 Macedonian traditional medicinal plants to improve its potential as a source of natural antioxidants. Antioxidant potential of plant extracts was analyzed by five different assays: cupric reducing antioxidant capacity (CUPRAC), phosphomolybdenum method (PM), reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH^·) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS^·+) radical scavenging activity. Origanum vulgare extract consistently exhibited the highest content of phenolic compounds and the strongest antioxidant capacity based on the tests performed, and can be proposed as a promising source of natural antioxidants. Melissa officinalis and Salvia ringens were also identified as valuable sources of antioxidant compounds. A positive linear correlation between antioxidant activity and total phenolics, flavonoids and phenylpropanoids indicates that these compounds are likely to be the main antioxidants contributing to the observed activities of evaluated plants. These findings suggest that the medicinal plants studied in this paper are good sources of bioactive compounds for the food and pharmaceutical industries.     

Comparative Analysis of Antioxidant Activities of Fourteen Mentha Essential Oils and Their Components

The essential oils of 14 species and hybrids, respectively, of the genus Mentha were examined for their antioxidant capacity in the ABTS (2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid)) assay and in a lipid‐peroxidation (LPO) assay. The ABTS^.+‐scavenging capacity of pure essential‐oil components and mixtures of them was also tested. In both assays, Mentha×dumetorum (classification not fully confirmed), Mentha suaveolens, and Mentha×villosa (classification not fully confirmed) showed the highest antioxidant capacity, which was ascribed to the components germacrene D, piperitone oxide, and piperitenone oxide. The high antioxidant activity in the LPO assay of the two hybrids Mentha×gracilis and, to a lower degree, of Mentha×dalmatica (classification not fully confirmed) was ascribed to their high contents of cis‐ocimene and β‐caryophyllene. Of the pure components tested (germacrene D, piperitone oxide, and piperitenone oxide were not tested, as not commercially available), only cis‐ocimene showed a distinct antioxidant effect, whereas dihydrocarvone and linalool had pro‐oxidant effects in the ABTS assay.     

Subcritical Water Extraction of Phenolic Compounds from Vaccinium Dunalianum Wight Leaves and Their Antioxidant and Tyrosinase Inhibitory Activities in Vitro

Subcritical water extraction was used to extract bioactive phenolic compounds from Vaccinium dunalianum Wight leaves. The optimal extraction conditions were determined as an extraction temperature of 150 °C, an extraction time of 40 min, and a liquid-solid ratio of 35 : 1 mL/g. The total phenolic content reached 21.35 mg gallic acid /g, which was 16 % higher than that by hot water extraction. The subcritical water extraction extract exhibited strong scavenging activity of DPPH free radical and ABTS⁺ free radical, as well as significant tyrosinase inhibitory activity. The study suggests that subcritical water extraction can alter the composition of the extracts, leading to the production of various phenolic compounds, effective antioxidants, and tyrosinase inhibitors from Vaccinium dulciana Wight leaves. These findings confirm the potential of Vaccinium dunalianum Wight as a natural antioxidant molecule source for the medicine and food industries, and for the therapy of skin pigmentation disorders.     

Total phenolic and flavonoid contents and antioxidant activity of ginger (Zingiber officinale Rosc.) rhizome,callus and callus treated with some elicitors

The present study was aimed at determining total phenolic and flavonoid contents and studying the antioxidant activity of ginger (Zingiber officinale Rosc.) rhizome and callus, 6-gingerol and 6-shogaol and callus treated with elicitors. Petroleum ether (PE) and chloroform: methanol (1:1, v/v) (CM) extracts were prepared by maceration. Highest total phenolic content was obtained from the CM extract (60.34?±?0.43?mg gallic acid/g) of rhizome while callus showed lower content detected in the CM extract (33.6?±?0.07?mg gallic acid/g). Flavonoids were only detected in rhizome (CM extract 40.25?±?0.21?mg quercetin/g). Both rhizome extracts exhibited good antioxidant activity with higher activity recorded in PE extract (IC₅₀ value 8.29?±?1.73?μg/mL). Callus extracts revealed lower antioxidant activity (IC₅₀ value 1265.49?±?59.9?μg/mL obtained from CM extract). 6-gingerol and 6-shogaol displayed high antioxidant activity in both assays with IC₅₀ 4.85?+?0.58_DPPH and 5.35?±?0.33_ABTS μg/mL for the former and IC₅₀ 7.61?±?0.81_DPPH and IC₅₀ 7.05?±?0.23_ABTS μg/mL for the latter. Treatment of callus with elicitors showed significant (p?<?0.05) effects in enhancing phenolic content and related antioxidant activity. The highest significant increase in phenolic content (37% and 34%) and antioxidant activity in DPPH assay (34% and 30%) was observed in callus treated with 100?mg/L yeast extract and 50?mg/L salicylic acid respectively. Therefore, studying the effect of the elicitation of ginger cultured tissues in phenolic accumulation would be of immense importance for pharmacological, cosmetic and agronomic industries.     

Extraction and Antioxidant Activities of Magnolia kwangsiensis Figlar & Noot. Leaf Polyphenols

Microwave‐assisted extraction was employed to extract polyphenols from the leaf of Magnolia kwangsiensis Figlar & Noot . The yield of polyphenols was 2.44±0.02 % under the optimal conditions of RSM: acetone concentration of 70 %, ratio of solvent to material of 21 mL?g^?1 and extraction time of 16 min. The antioxidant activities were evaluated in terms of total antioxidant ability, reducing power, DPPH ^? and ^? OH scavenging activity. Results showed the polyphenols presented potential antioxidant activities, especially the stronger scavenging activity on ^? OH. In term of ^? OH scavenging activity, the IC₅₀ value of NKA‐9 purification was 0.335 mg mL^?1, equivalent to 35.23 % of V_C. The IC₅₀ values of crude extract and ethyl acetate extract were 0.580 and 0.828 mg mL^?1, equivalent to 60.99 % and 87.07 % of V_C. Results indicated that M. kwangsiensis leaf polyphenols present potential antioxidant activities that make it beneficial for human health by preventing or reducing oxidative damage.     

Novel fluorine‐containing chiral hydrazide‐hydrazones: Design,synthesis, structural elucidation,antioxidant and anticholinesterase activity,and in silico studies

In this study, a series of fluorine‐containing chiral hydrazide‐hydrazone derivatives [III‐XII] from ?‐cysteine ethyl ester hydrochloride was synthesized as new antioxidant and anticholinesterase agents. The antioxidant activity of these derivatives was evaluated by ABTS^+· and DPPH^· scavenging and CUPRAC assays and the anticholinesterase activity by the Ellman method spectrophotometrically. The results of the antioxidant assay showed that compounds V , IX , and X exhibited higher activity than BHT and α‐tocopherol used as positive standards. Among the synthesized derivatives, compound IX (IC₅₀: 2.3 ± 1.6 μM) exhibited higher acetylcholinesterase inhibitory activity than galantamine (IC₅₀: 4.5 ± 0.8 μM). Compounds XI (IC₅₀: 9.6 ± 1.0 μM), IX (IC₅₀: 12.5 ± 1.6 μM), III (IC₅₀: 16.0 ± 1.6 μM), X (IC₅₀: 17.2 ± 1.8 μM), VI (IC₅₀: 20.2 ± 0.8 μM), XII (IC₅₀: 21.5 ± 1.0 μM), and VII (IC₅₀: 24.6 ± 0.6 μM) displayed better butyrylcholinesterase inhibitory activity than galantamine (IC₅₀: 46.03 ± 0.14 μM). ADME‐Tox analysis was used to probe the drug‐like properties of the compounds. Molecular docking studies were also applied to understand the interactions between compounds and targets. The docking calculations were supported by the experimental data. In particular, compound IX , having better activity than galantamine against acetylcholinesterase and butyrylcholinesterase enzymes, was visualized using molecular docking.