TAC Assays Research Articles

Antioxidant Activity of Leaf Extracts from Stevia rebaudiana Bertoni Exerts Attenuating Effect on Diseased Experimental Rats: A Systematic Review and Meta-Analysis.

Stevia (Stevia rebaudiana Bertoni) is an aromatic plant known for its high sweetening power ascribed to its glycosides. Stevia also contains several bioactive compounds showing antioxidant, antiproliferative, antimicrobial, and anti-inflammatory activities. Since inflammation and oxidative stress play critical roles in the pathogenesis of many diseases, stevia emerges as a promising natural product that could support human health. In this study we set out to investigate the way stevia affects oxidative stress markers (e.g., SOD, CAT, GPx, GSH, MDA) in diseased rats administered stevia leaf extracts or glycosides. To this end, we performed an inclusive literature search, following PRISMA guidelines, and recruited multivariate meta-analysis and meta-regression to synthesize all available data on experimental animal models encountering (a) healthy, (b) diseased, and (c) stevia-treated diseased rats. From the 184 articles initially retrieved, 24 satisfied the eligibility criteria, containing 104 studies. Our results demonstrate that regardless of the assay employed, stevia leaf extracts restored all oxidative stress markers to a higher extent compared to pure glycosides. Meta-regression analysis revealed that results from SOD, CAT, GSH, and TAC assays are not statistically significantly different (p = 0.184) and can be combined in meta-analysis. Organic extracts from stevia leaves showed more robust antioxidant properties compared to aqueous or hydroalcoholic ones. The restoration of oxidative markers ranged from 65% to 85% and was exhibited in all tested tissues. Rats with diabetes mellitus were found to have the highest restorative response to stevia leaf extract administration. Our results suggest that stevia leaf extract can act protectively against various diseases through its antioxidant properties. However, which of each of the multitude of stevia compounds contribute to this effect, and to what extent, awaits further investigation.

Conocarpus lancifolius (Combretaceae): Pharmacological Effects, LC-ESI-MS/MS Profiling and In Silico Attributes.

In folklore medicine, Conocarpus lancifolius is used to treat various illnesses. The main objective of this study was a comprehensive investigation of Conocarpus lancifolius leaf aqueous extract (CLAE) for its antioxidant, cardioprotective, anxiolytic, antidepressant and memory-enhancing capabilities by using different in vitro, in vivo and in silico models. The in vitro experimentation revealed that CLAE consumed an ample amount of total phenolics (67.70 ± 0.15 µg GAE/mg) and flavonoids (47.54 ± 0.45 µg QE/mg) with stronger antiradical effects through DPPH (IC50 = 16.66 ± 0.42 µg/mL), TAC (77.33 ± 0.41 µg AAE/mg) and TRP (79.11 ± 0.67 µg GAE/mg) assays. The extract also displayed suitable acetylcholinesterase (AChE) inhibitory (IC50 = 110.13 ± 1.71 µg/mL) activity through a modified Ellman's method. The toxicology examination presented no mortality or any signs of clinical toxicity in both single-dose and repeated-dose tests. In line with the cardioprotective study, the pretreatment of CLAE was found to be effective in relieving the isoproterenol (ISO)-induced myocardial injury in rats by normalizing the heart weight index, serum cardiac biomarkers, lipid profile and various histopathological variations. In the noise-stress-induced model for behavior attributes, the results demonstrated that CLAE has the tendency to increase the time spent in the central zone and elevated open arms in the open field and elevated plus maze tests (examined for anxiety assessment), reduced periods of immobility in the forced swimming test (for depression) and improved recognition and working memory in the novel object recognition and Morris water maze tests, respectively. Moreover, the LC-ESI-MS/MS profiling predicted 53 phytocompounds in CLAE. The drug-likeness and ADMET analysis exhibited that the majority of the identified compounds have reasonable physicochemical and pharmacokinetic profiles. The co-expression of molecular docking and network analysis indicated that top-ranked CLAE phytoconstituents act efficiently against the key proteins and target multiple signaling pathways to exert its cardiovascular-protectant, anxiolytic, antidepressant and memory-enhancing activity. Hence, this artifact illustrates that the observed biological properties of CLAE elucidate its significance as a sustainable source of bioactive phytochemicals, which appears to be advantageous for pursuing further studies for the development of new therapeutic agents of desired interest.

Exploring the Multi-Faceted Potential of Carob (Ceratonia siliqua var. Rahma) Leaves from Morocco: A Comprehensive Analysis of Polyphenols Profile, Antimicrobial Activity, Cytotoxicity against Breast Cancer Cell Lines, and Genotoxicity.

The botanical species Ceratonia siliqua L., commonly referred to as the Carob tree, and locally as "L'Kharrûb", holds significance as an agro-sylvo-pastoral species, and is traditionally utilized in Morocco for treating a variety of ailments. This current investigation aims to ascertain the antioxidant, antimicrobial, and cytotoxic properties of the ethanolic extract of C. siliqua leaves (CSEE). Initially, we analyzed the chemical composition of CSEE through high-performance liquid chromatography with Diode-Array Detection (HPLC-DAD). Subsequently, we conducted various assessments, including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, and total antioxidant capacity assays to evaluate the antioxidant activity of the extract. In this study, we investigated the antimicrobial properties of CSEE against five bacterial strains (two gram-positive, Staphylococcus aureus, and Enterococcus faecalis; and three gram-negative bacteria, Escherichia coli, Escherichia vekanda, and Pseudomonas aeruginosa) and two fungi (Candida albicans, and Geotrichum candidum). Additionally, we evaluated the cytotoxicity of CSEE on three human breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-436) and assessed the potential genotoxicity of the extract using the comet assay. Through HPLC-DAD analysis, we determined that phenolic acids and flavonoids were the primary constituents of the CSEE extract. The results of the DPPH test indicated a potent scavenging capacity of the extract with an IC50 of 302.78 ± 7.55 µg/mL, which was comparable to that of ascorbic acid with an IC50 of 260.24 ± 6.45 µg/mL. Similarly, the β-carotene test demonstrated an IC50 of 352.06 ± 12.16 µg/mL, signifying the extract's potential to inhibit oxidative damage. The ABTS assay revealed IC50 values of 48.13 ± 3.66 TE µmol/mL, indicating a strong ability of CSEE to scavenge ABTS radicals, and the TAC assay demonstrated an IC50 value of 165 ± 7.66 µg AAE/mg. The results suggest that the CSEE extract had potent antioxidant activity. Regarding its antimicrobial activity, the CSEE extract was effective against all five tested bacterial strains, indicating its broad-spectrum antibacterial properties. However, it only showed moderate activity against the two tested fungal strains, suggesting it may not be as effective against fungi. The CSEE exhibited a noteworthy dose-dependent inhibitory activity against all the tested tumor cell lines in vitro. The extract did not induce DNA damage at the concentrations of 6.25, 12.5, 25, and 50 µg/mL, as assessed by the comet assay. However, the 100 µg/mL concentration of CSEE resulted in a significant genotoxic effect compared to the negative control. A computational analysis was conducted to determine the physicochemical and pharmacokinetic characteristics of the constituent molecules present in the extract. The Prediction of Activity Spectra of Substances (PASS) test was employed to forecast the potential biological activities of these molecules. Additionally, the toxicity of the molecules was evaluated using the Protox II webserver.

Phenolic Profile, Inhibition of α-Amylase and α-Glucosidase Enzymes, and Antioxidant Properties of Solanum elaeagnifolium Cav. (Solanaceae): In Vitro and In Silico Investigations

In this study, the chemical composition and the antioxidant and antidiabetic properties of S. elaeagnifolium flower (SEFl), fruit (SEFr), and leaf (SEFe) extracts were investigated in vitro and in silico. HPLC-DAD analysis was used to determine the chemical components. Colorimetric techniques were used to identify polyphenols and flavonoids. The antioxidant capacity was determined using DPPH and TAC assays. The antidiabetic activity was examined using the enzymes α-amylase and α-glucosidase. Molecular docking methods were used to assess the anti-dipeptidyl peptidase IV (DPP-IV) activity. According to HPLC findings, extracts of S. elaeagnifolium flowers, leaves, and fruits are rich in salicylic acid, sinapic acid, chlorogenic acid, naringin, quercetin, quercetin-3-O-beta-glucoside, kaempferol, and chalcone. The IC50 for flower, leaf, and fruit extracts were 132 ± 5.59 μg/mL, 43.19 ± 1.46 μg/mL, and 132 ± 5.59 μg/mL, respectively. The total antioxidant capacity of SEFr, SEFe, and SEFl were determined to be 900.06 ± 4.01 μg AAE/mg, 792.10 ± 6.72 μg AAE/mg, and 681.10 ± 3.02 μg AAE/mg, respectively. Importantly, SEFe, SEFl, and SEFr displayed significant anti-α-amylase activity, with IC50 values of 79.16 ± 2.35 µg/mL, 99.16 ± 1.17 µg/mL, and 40.31 ± 2.04 µg/mL, respectively. The results also showed that SEFr, SEFe, and SEFl all exhibited potent anti-α-glucosidase activity, whose IC50 values were determined to be 20.53 ± 0.37 µg/mL (SEFr), 20.05 ± 0.12 µg/mL (SEFe), and 41.1 ± 1.55 µg/mL (SEFl). Molecular docking of S. elaeagnifolium phenolic compounds in the active site of DPP-IV revealed a strong inhibitory effect, with a glide score ranging from −2.63 to −8.10 Kcal/mol. Notably—with glide scores of −8.10, −6.23, −5.73, and −5.37 Kcal/mol—rutin, quercetin-3-O-beta-glucoside, chalcone, and naringin were the most active molecules against DPP-IV.

Comprehensive screening and characterization of polyphenol compounds from pasture grasses used for livestock production under temperate region

Pasture grasses and legumes have a wide range of polyphenol compounds of which have potential antioxidant capacity. In recent years, polyphenol compounds from forages have gained attention due to their health-promoting abilities, but comprehensive profiling of these forages is still in shadow. Therefore, the purpose of this study was to comprehensively profile the polyphenol compounds in pasture grasses, legumes and novel forages collected during successive seasons of winter, spring, and summer. A total of 31 compounds were tentatively identified in which 11 compounds are phenolic acid, 10 were flavonoids, and 10 were other polyphenols. Among all forages collected, chicory and perennial ryegrass contained higher phenolic acid concentrations, while plantain, brassica and lucerne contained higher concentrations of flavonoids. Forages harvested during the winter and spring seasons have higher polyphenol concentrations and antioxidant potential than those samples collected in summer. The ethanolic extracts of plantain harvested during winter contained the highest concentration of total phenolic content (16.83 ± 0.95 mg GAE/g DW) and chicory showed total flavonoids content (1.51 ± 0.12 mg QE/g DW) in winter. Plantain harvested during spring showed the highest concentration of total condensed tannins (18.81 ± 0.36 mg CE/g DW). Spring- chicory (21.30 ± 1.42 mg Trolox/g DW), winter- plantain (25.71 ± 0.26 mg AAE/g DW), winter-plantain (0.5 ± 0.07 mg AAE/g DW), spring- plantain (5.33 ± 0.07 mg AAE/g DW), winter-lucerne (4.77 ± 0.12 mg EDTA/g DW), summer-plantain (27.83 ± 0.83 mg AAE/g DW), and winter- plantain (57.87 ± 3.67 mg/Trolox/g DW) showed highest concentration of antioxidant potential in DPPH, ABTS, FRAP, RPA, FICA, •OH-RSA, and TAC assays, respectively. This study suggests that as the season moves from winter to spring to summer, the polyphenol concentrations in the forages decline, probably due to pasture maturity or dry climatic conditions, or a combination of both.

Volatile Constituents in Essential Oil from Leaves of Withania adpressa Coss. Ex Exhibit Potent Antioxidant and Antimicrobial Properties against Clinically-Relevant Pathogens.

Withania adpressa Coss. ex is a plant used in traditional medications. Antioxidant, antibacterial, and antifungal properties of the essential oil from leaves of Withania adpressa Coss ex. (EOW) were investigated. EOW was extracted using a Clevenger apparatus, and its volatile compounds were characterized by GC-MS. Antioxidant potency was determined using DPPH, FRAP, and TAC assays. Antibacterial effects were determined vs. Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Streptococcus pneumonia; while its antifungal efficacy was determined vs. Candida albicans, Aspergillus flavus, Aspergillus niger, and Fusarium oxysporum using the disc diffusion and minimum inhibitory concentration bioassays. A chromatographic analysis showed that EOW contained eight phytochemical compounds constituting 99.14% of the total mass of oil. Caryophyllene (24.74%), Longifolene (21.37%), δ-Cadinene (19.08%), and Carene (14.86%) were predominant compounds in EOW. The concentrations required to inhibit 50% of free radical (IC50) values of antioxidant activities of EOW were 0.031 ± 0.006 mg/mL (DPPH), 0.011 ± 0.003 mg/mL (FRAP), and 846.25 ± 1.07 mg AAE/g (TAC). Inhibition zone diameters of EOW vs. bacteria were 18.11 ± 0.5 mm (E. coli), 17.10 ± 0.42 mm (S. aureus), 12.13 ± 0.31 mm (K. pneumoniae), and 11.09 ± 0.47 mm (S. pneumoniae), while MIC values were 51 ± 3, 47 ± 5, 46 ± 3 and 31 ± 1 µg/mL, respectively. Inhibition zone diameters of EOW vs. fungi were 31.32 ± 1.32, 29.00 ± 1.5, 27.63 ± 2.10, and 24.51 ± s1.07 mm for A. flavus, C. albicans, F. oxysporum, and A. niger, respectively. MIC values were 8.41 ± 0.40, 28.04 ± 0.26, 9.05 ± 0.76, and 22.26 ± 0.55 µg/mL, respectively. Importantly, the highest dose of EOW (1 mg/mL) showed negligible (~5%) cytotoxicity against MCF-12, a normal human epithelial cell line derived from the mammary gland, thus underscoring its wide safety and selectivity against tested microbes. To sum it up, EOW has exhibited promising antioxidant and antimicrobial properties, which suggests potential to abrogate antibiotic resistance.

Evaluation of Pharmacological Potential of Miliusa nilagirica Bedd. Leaves Using In Vitro Antidiabetic and Antioxidant Assays.

Miliusanilagirica, a rare tree species of Western Ghats, belongs to the Annonaceae family, a family with potential antioxidant and antidiabetic properties. This study is designed vividly to establish the relationship between the constituent phytochemicals and their hyperglycemic effects through the antioxidant traits of M. nilagirica in vitro. Phytochemical tests were conducted on dry powdered leaves and extracts of various methods to determine the existence of various constituents. The antidiabetic potential of leaf extracts was estimated by using the α-amylase inhibitory model and the antioxidant potential was estimated with various assays. The quantitative phytochemical screening of leaf parts shows the presence of carbohydrates (88.74 ± 0.65mg GE/g sample), proteins (82.17 ± 2.52mg BSAE/g sample), phenolics (40.44 ± 0.43 GAE/100g), and flavonoids (66.05 ± 0.48mg RE/g extract). Methanol extract of Soxhlet of M. nilagirica registered the strongest antioxidant activity in all assays, 75.66% inhibition (DPPH assay), 795.01µmol/g (ABTS˙+ radical scavenging), 994.33µmol/g (FRAP assay), 362.02mg AAE/g extract (TAC assay), 47% inhibition (NO scavenging assay). In vitro α-amylase inhibition showed a highly noticeable reduction in ethyl acetate extract from Soxhlet (75.19%). HPLC and FTIR analyses on the extracts added strengths to the obtained results on the potentiality of M. nilagirica. From the results, it is evident that phytochemicals from M. nilagirica can be studied further, isolated, and incorporated as an alternative to synthetic supplements for hyperglycemia.

The protective effects of astaxanthin on pre-antral follicle degeneration in ovine vitrified/warmed ovarian tissue

This study assesses the protective effects of astaxanthin (AST) against vitrification/warming-induced cryoinjuries of ovarian tissue slices in sheep. Cortical slices of slaughterhouse acquired-ovine ovaries were randomly distributed in different groups: fresh, toxicity, and five vitrification groups including vitrification in presence of 0 (control group), 1, 10 and 100 μM astaxanthin or 100 μM vitamin E. After vitrification/warming and 24 h culturing, the samples were subjected to histological studies, antioxidant evaluation by TAC and TBAR assays, and assessment of relative expression of BMP4, BMP15, GDF9 and KITLG genes related to folliculogenesis and follicular growth regulation. According to the results, vitrification reduced the percentage of morphologically intact follicles compared to the fresh and toxicity groups (p < 0.05). In vitrification groups, vitamin E and all three concentrations of AST increased the percentage of intact pre-antral follicles and antioxidant activity relative to the vitrified control (p < 0.05). This enhancement significantly occurred in 10 μM AST group more than vitamin E (p < 0.05). Also, 10 μM concentration of AST enhanced the expression of all the examined genes compared to the control (p < 0.05), while the expression of BMP4, BMP15 and KITLG was higher in the AST than vitamin E (p < 0.05). The latter could increase only the expression of GDF9 compared to the control group (p = 0.011). In conclusion, AST is a highly effective antioxidant for maintaining the survival of pre-antral follicles, retaining cell density, increasing total antioxidant capacity, and increasing the expression of some genes related to follicular development after short-term culture of vitrified/warmed ovarian tissue slices.

LC-MS/MS and GC/MS Profiling of Petroselinum sativum Hoffm. and Its Topical Application on Burn Wound Healing and Related Analgesic Potential in Rats.

Parsley (Petroselinum sativum Hoffm.) is renowned for its ethnomedicinal uses including managing pain, wound, and dermal diseases. We previously highlighted the estrogenic and anti-inflammatory properties of parsley and profiled the phytochemistry of its polyphenolic fraction using HPLC-DAD. To extend our investigation, we here characterized the phytochemical composition of the hydro-ethanolic extract using LC-MS/MS and GC-MS upon silylation, and evaluated the antioxidant, analgesic, antimicrobial, and wound healing activities of its hydro-ethanolic and polyphenolic fraction. The antioxidant property was assessed using FRAP, DPPH, and TAC assays. The antimicrobial activity was tested against four wound infectious microbes (Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans). The analgesic effect was studied using acetic acid (counting the number of writhes) and formalin (recording the licking and biting times) injections while the wound healing activity was evaluated using burn model in vivo. The LC-MS/MS showed that the hydro-ethanolic contains four polyphenols (oleuropein, arbutin, myricetin, and naringin) while GC-MS revealed that it contains 20 compounds including malic acid, D-glucose, and galactofuranoside. The hydro-ethanolic (1000 mg/kg) decreased abdominal writhes (38.96%) and licking time (37.34%). It also elicited a strong antioxidant activity using DPPH method (IC50 = 19.38 ± 0.15 µg/mL). Polyphenols exhibited a good antimicrobial effect (MIC = 3.125-12.5 mg/mL). Moreover, both extracts showed high wound contraction by 97.17% and 94.98%, respectively. This study provides evidence that P. sativum could serve as a source of bio-compounds exhibiting analgesic effect and their promising application in mitigating ROS-related disorders, impeding wound infections, and enhancing burn healing.

Spectral, DFT, thermal, electrochemical, and biological investigations on Cu2+, Cd2+, and Mn2+ complexes of favipiravir ligand

A series of bivalent Cu2+, Cd2+, and Mn2+ metal complexes were prepared with 6-fluoro-3-hydroxypyrazine-2-carboxamide (favipiravir) ligand (L) and structurally characterized via many spectroscopic techniques (IR, UV–vis, 1H NMR, 13C NMR, ESI-MS & powder XRD) besides the elemental analysis and magnetic moment measurements. The complexes were also investigated by thermal studies (TG/DTA) accompanied by kinetic investigations based on Coats-RedfernandHorowitz-Metzgerintegralmethods. The ligand and its metal complexes were geometric optimized using the Gaussian 09 view based on DFT theory. Through cyclic voltammetric scanning with/without the ligand, the complexation effect on Cu+2 was studied electrochemically in solution. Finally, the antimicrobial assays including (Escherichia coli, Bacillus cereus, and Candida albicans) were screened for all compounds to calculate the % activity index and MIC. In addition, the antioxidant activity was investigated using DPPH and TAC assays.

Phytochemical Screening and In vitro Antioxidant, Antibacterial, and Antihemolytic Activities of Putoria calabrica Leaf Extracts

Background:: Putoria calabrica is a common Mediterranean plant used topically in folk medicine for medical purposes. The aim of this study is to evaluate the in vitro antioxidant, antibacterial, and antihemolytic properties of Putoria calabrica leaf extracts.Methods:Total phenol content (TPC), total flavonoid content (TFC), and condensed tannins content (CTC) were determined spectrophotometrically. The antioxidant activity was tested using TAC, DPPH, ABTS, and FRAP assays. Agar diffusion method was used to determine the antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. Anti-hemolytic activity was evaluated by the measurement of erythrocytes turbidity and extracellular hemoglobin concentration using AAPH method.Results:Methanol was the optimal solvent to extract the bioactive components with the highest extraction yield (30.11 ± 0.42%), TPC (142.11 ± 4.04 mg GAE/g dry extract) and TFC (29.16 ± 0.99 mg QrE/g dry extract). In terms of antioxidant activity, methanol extract was the most effective against ABTS free radical (IC50 = 5.02 ± 0.13 mg/ml) and FRAP (A0.5 = 2.91 ± 0.09 mg/ml). While, acetone extract showed the highest TAC (214.05 ± 8.74 mg GAE/g dry extract) and DPPH scavenging activity (IC50 = 1.94 ± 0.02 mg/ml). The strongest antimicrobial effect at a concentration of 10.24 mg/well was observed with acetone extract against P. aeruginosa (22.52 ± 0.60 mm) and C. albicans (17.33 ± 0.41 mm). While, methanol extract was the most active against S. aureus (17.31 ± 0.98 mm). Aqueous extract showed a good capacity to protect erythrocytes from oxidative damage by preventing their hemolysis and the oxidation of hemoglobin induced by AAPH.Conclusion:P. calabrica leaves could have a great importance as a source of therapeutic bioactive compounds.

Convolvulus arvensis: Antioxidant, Antibacterial, and Antifungal Properties of Chemically Profiled Essential Oils: An Approach against Nosocomial Infections.

Convolvulus arvensis is a medicinal plant in the family Convolvulaceae, which is used in traditional phytotherapy. The objective of this work was conducted to valorize essential oils of Convolvulus arvensis (EOCA) in terms of chemical composition, antioxidant, and antibacterial properties. To achieve this objective, the chemical composition was performed by the use of GC-SM. Antioxidant power was effectuated by the use of DPPH, FRAP, and TAC assays. Evaluation of the antimicrobial power was conducted against clinically important pathogenic bacteria (E. coli, K. pneumoniae, S. pneumoniae, and S. aureus) and fungi (A. niger, C. albicans, and A. flavus) by the use of disc diffusion and minimum inhibitory concentrations (MICs) assays. The results showed that the yield of recovered EOs from Convolvulus arvensis was 0.34% of the total mass of leaves and mainly was rich in cuprenne (34%), thymol (20%), himachalene (16%), and longifolene (10%). Notably, EOCA exhibited important antioxidant effects, wherein IC50 (DPPH) and EC50 (FRAP) were determined to be 30 µg/mL and 120 µg/mL, respectively, while the total antioxidant power was determined to be 508.0 ± 6.0 µg EAA/mg. An important antibacterial effect was noted for EOCA as an excellent inhibition zone was recorded against all bacterial strains, particularly K. pneumoniae and S. aureus with 14.27 ± 0.42 and 21.35 ± 0.76 mm, respectively. Similarly, MICs of K. pneumoniae and S. aureus were 21.35 ± 0.76 mm and 28.62 ± 1.65 µg/mL, respectively. Noticeably, important antifungal activity was shown by EOCA against all fungal strains wherein the inhibition zone diameters against all fungal species ranged from 19.44 ± 1.10 to 20.41 ± 1.81 mm. Notably, MICs of EOCA against F. oxysporum and C. albicans were 18.65 ± 0.94 and 19.38 ± 0.58 g/mL, respectively. The outcome of the present work showed that EOs from Convolvulus arvensis can be used to conceptualize drugs to manage diseases relative to free radicals and infections.

Solanum elaeagnifolium Var. Obtusifolium (Dunal) Dunal: Antioxidant, Antibacterial, and Antifungal Activities of Polyphenol-Rich Extracts Chemically Characterized by Use of In Vitro and In Silico Approaches.

The present work was designed to study the chemical composition and the antioxidant and antimicrobial properties of fruits (SFr) and leaf (SF) extracts from Solanum elaeagnifolium var. obtusifolium (Dunal) Dunal (S. elaeagnifolium). The chemical composition was determined using HPLC-DAD analysis. Colorimetric methods were used to determine polyphenols and flavonoids. Antioxidant capacity was assessed with DPPH, TAC, and FRAP assays. Antimicrobial activity was assessed using disk diffusion and microdilution assays against two Gram (+) bacteria (Staphylococcus aureus ATCC-6633 and Bacillus subtilis DSM-6333) and two Gram (-) bacteria (Escherichia coli K-12 and Proteus mirabilis ATCC-29906), while the antifungal effect was tested vs. Candida albicans ATCC-1023. By use of in silico studies, the antioxidant and antimicrobial properties of the studied extracts were also investigated. HPLC analysis showed that both fruits and leaf extracts from S. elaeagnifolium were rich in luteolin, quercetin, gallic acid, and naringenin. Both SFr and SF generated good antioxidant activity, with IC50 values of 35.15 ± 6.09 μg/mL and 132.46 ± 11.73 μg/mL, respectively. The EC50 of SFr and SF was 35.15 ± 6.09 μg/mL and 132.46 ± 11.73 μg/mL, respectively. SFr and SF also showed a good total antioxidant capacity of 939.66 ± 5.01 μg AAE/and 890.1 ± 7.76 μg AAE/g, respectively. SFr had important antibacterial activity vs. all tested strains-most notably B. subtilis DSM-6333 and E. coli, with MICs values of 2.5 ± 0.00 mg/mL and 2.50 ± 0.00 mg/mL, respectively. SFr demonstrated potent antifungal activity against C. albicans, with an inhibition diameter of 9.00 ± 0.50 mm and an MIC of 0.31 ± 0.00 mg/mL. The in silico approach showed that all compounds detected in SFr and SF had high activity (between -5.368 and 8.416 kcal/mol) against the receptors studied, including NADPH oxidase, human acetylcholinesterase, and beta-ketoacyl-[acyl carrier protein] synthase.

Alcoholic fermentation with Pichia kluyveri could improve the melatonin bioavailability of orange juice

• Fermented orange juice (FOJ) intake increases urine 6-sulfatoxymelatonin (6-SMT). • Urine antioxidant activity is higher after FOJ consumption than after OJ consumption. • Urine antioxidant activity after FOJ intake would be mainly due to 6-SMT content. • FOJ could be a good source of bioavailable melatonin. Fermentation of orange juice (OJ) by Pichia kluyveri enhances the content of melatonin, a molecule with potent antioxidant effect. This study explores the levels of urine 6- sulfatoxymelatonin (6-SMT) in healthy subjects after fermented orange juice (FOJ) intake, and their association with antioxidant activity status. Nine participants ingested 500 mL of FOJ and their urine was collected at baseline and after 2, 5, 10, 15 and 24 h. After a two-week washout period, the intervention was repeated with OJ. 6-SMT levels were quantified by ELISA and antioxidant activity by TAC, FRAP and ORAC assays. A significant increase in both 6-SMT levels and antioxidant activity in urine was observed after FOJ ingestion compared to OJ. A positive correlation between TAC and 6-SMT levels was observed only after FOJ intake. This study shows for the first time that fermentation process increases melatonin bioavailability of OJ associated with an enhancement in antioxidant status.

Bioactive phytosteroids from Araucaria columnaris (G. Forst.) Hook.: RP-HPLC-DAD analysis, in-vitro antioxidant potential, in-silico computational study and molecular docking against 3MNG and 1N3U

Genus Araucaria is globally known for its medicinal, economic, and ornamental values. Most of its species have not been extensively studied yet for their chemical composition and biological activities. Therefore, the phytochemical investigation and antioxidant potential of Araucaria columnaris (G. Forst.) Hook. has been analyzed. This work aims to investigate the isolation, characterization, and antioxidant potential of bioactive compounds from the bark extract of the exemplar plant. Their structures were elucidated by virtue of physicochemical properties and spectroscopic methods. The antioxidant potential was further discussed through various assays including DFT and molecular docking. The isolation of pure compounds from bioactive extract has been carried out chromatographically. Their structures were elucidated by 1D, 2D NMR, FT-IR, UV, MS, and RP-HPLC-DAD data analysis. In vitro, the antioxidant potential was evaluated by the DRSC, FRAP, and TAC assays and in-silico studies by DFT and molecular docking. For the first time, pure compounds such as stigmasterol (IC1) and diosgenin (IC2) were isolated from the bark extract of Araucaria columnaris. In vitro antioxidant activity has been demonstrated that IC2 has higher values of DRSC, FRAP, and TAC than IC1, due to higher reactivity of IC2 than IC1 as represented by quantum reactivity parameters like lower energy gap, higher dipole moment, and higher electron-donor power. Further, antioxidant potential was also confirmed by molecular docking against two stress proteins such as 3MNG (IC2: −7.70 Kcal/mol > IC1: −7.32 Kcal/mol > ascorbic acid: −5.56 Kcal/mol) and 1N3U (heme: −12.42 Kcal/mol > IC2: −11.15 Kcal/mol > IC1: −9.45 Kcal/mol). In conclusion, the phytosteroids exhibited excellent antioxidant potential, which could enlighten their ethnomedical use. The exemplar plant offered powerful and available antioxidant besides significantly active phytoconstituents.

In Vitro and In Vivo Digestive Fate and Antioxidant Activities of Polyphenols from Hulless Barley: Impact of Various Thermal Processing Methods and β-Glucan.

The unfavorable bioaccessibility of polyphenols in cereal-based food limits their physiological functions as most polyphenols bind spontaneously to the cell-wall polysaccharides. Effects of β-glucan and various thermal processing methods including flaking and roasting, stir-frying, steam-flash explosion, and popping expansion on the bioaccessibility and antioxidant properties of polyphenols from hulless barley in vitro and in vivo were investigated in this study. The bioaccessibility and antioxidant capacity (via DPPH, ·OH, and ·O2- free radical scavenging, TAC, and FRAP assays) of polyphenol extracts from hulless barley treated by steam-flash explosion and popping expansion increased significantly before and after in vitro digestion compared to those from raw and other processed hulless barley. Further, the total polyphenol content of hulless barley elevated dramatically following hydrolyzing with β-glucanase, which was positively correlated with the antioxidant activity. Additionally, the hulless barley treated with steam-flash explosion exhibited potent antidiabetic effects and antioxidant capacity (via TAC, SOD, GSH-Px, CAT, and MDA assays) in type 2 diabetic rats. The absorption of individual phenolic compounds in the alimentary canal of rats was impacted obviously by thermal processing. This study provides new insights into enhancing the bioaccessibility of the polyphenols and suggests that β-glucans interact with polyphenols and proteins in the hulless barley matrix.

Hieracium waldsteinii (Asteraceae) and Onosma stellulata (Boraginaceae) as a Source of Antioxidant and Antimicrobial Agents

AbstractThe current study aimed to phytochemically characterize (including a detailed phenolic profile) two endemic Balkan's species (Hieracium waldsteinii and Onosma stellulata) and determine their possible application as a source of natural antioxidant and antimicrobial agents. The main phenolic compound in both species (in all examined parts) was chlorogenic acid. Eriodictyol, genistein and naringenin were quantified only in H. waldsteinii while isorhamnetin‐3‐O‐rutinoside and sinapic acid were characteristic for O. stellulata. The highest antioxidant activity (98 mg AAE/g dry weight for TAC assay) was ascribed to the flower extract of H. waldsteinii while the lowest results (∼4.3 mg AAE/g dry weight for FRP assay) were exhibited by the extracts obtained from the plant's stem. Antimicrobial assays showed moderate antibacterial, i. e., moderate/strong activity against several tested fungi (in particular Trichoderma viride). Correlation analysis revealed strong positive connection between phenolic compounds and reducing power of extracts as well as between total phenolic and flavonoid content and the obtained minimal inhibitory concentration recorded in antibacterial assays.

Antioxidant, Anticancer, and PXR-Dependent CYP3A4 Attributes of Schweinfurthia papilionacea (Burm.f.) Boiss., Tricholepis glaberrima DC. and Viola stocksii Boiss.

Present study established the biological potential of Schweinfurthia papilionacea, Tricholepis glaberrima and Viola stocksii extracts for their potential applications in drug formulations. Initially, FTIR was performed to ascertain functional groups and then plant extracts were prepared using five solvents depending on the polarity. Total phenolic contents were observed in the range of 36.36 ± 1.08 mg GAE/g to 95.55 ± 2.46 mg GAE/g while flavonoid contents were found in the range of 10.51 ± 0.25 mg QE/g to 22.17 ± 1.79 mg QE/g. Antioxidant activity was determined using TRP, CUPRAC, TAC and DPPH assays and was recorded highest in S. papilionacea followed by T. glaberrima extracts. TPC and TFC were found to be strongly correlated with TRP (r > 0.50), CUPRAC (r > 0.53) and DPPH (r = 0.31 and 0.72) assay while weakly correlated with TAC (r = 0.08 and 0.03) as determined by Pearson correlation analysis. Anticancer activity showed that S. papilionacea chloroform extracts possess highest cell viability (85.04 ± 4.24%) against HepG2 cell lines while T. glaberrima chloroform extracts exhibited highest activity (82.80 ± 2.68%) against HT144 cell lines. Afterwards, highest PXR activation was observed in T. glaberrima (3.49 ± 0.34 μg/mL fold) at 60 μg/mL and was correlated with increase in CYP3A4 activity (15.0 ± 3.00 μg/mL IC50 value). Furthermore, antimalarial activity revealed >47600 IC50 value against P. falciparum D6 and P. falciparum W2 and antimicrobial assay indicated highest activity (32 ± 2.80 mm) in S. papilionacea against C. neoformans. At the end, GC-MS analysis of n-hexane plant extracts showed 99.104% of total identified compounds in T. glaberrima and 94.31% in V. stocksii. In conclusion, present study provides insight about the different biological potentials of S. papilionacea and T. glaberrima extracts that rationalize the applications of these extracts in functional foods and herbal drugs for the management of oxidative-stress related diseases, antimicrobial infections and liver and skin cancer.

An Assessment of Cataract Severity Based on Antioxidant Status and Ascorbic Acid Levels in Aqueous Humor.

Cataract is the leading cause of blindness throughout the world. Currently, the cataract severity evaluation is based on the subjective LOCS III guideline. To ameliorate the evaluation system and develop an objective and quantitative analysis, we investigated the relationships among aqueous humor total antioxidant capacity (AqTAC), ascorbic acid (AqAA) concentration, and cataract severity. In this study, we enrolled 130 cataract patients who underwent phacoemulsification between April 2019 and March 2020. The AqTAC and AqAA were measured by our own developed TAC assay and commercially available kit. Cataract severity was recorded by nuclear opalescence (NO) and cortical cataract (CC) degree according to LOCS III. Cumulative dissipated energy (CDE) during phacoemulsification was recorded to verify the severity of the cataract. As a result, we found a moderate correlation between AqTAC and CDE (p < 0.001). In addition, we found AqTAC independently associated with the CDE when analyzed by multivariate linear regression (p < 0.001). AqTAC also negatively correlated to cataract severity when measured by NO and CC (p = 0.012 in NO grade 3 vs. grade 1; p = 0.012 in CC grade 2 vs. grade 1; p < 0.001 in CC grade 3 vs. grade 1). We further found AqAA provided 71.9 ± 13.5% of AqTAC, and showed a high correlation (rho = 0.79, p < 0.001). In conclusion, we found a significant correlation between AqTAC/AqAA and cataract severity measured by CDE. The correlation was superior to the correlation between LOCS III and CDE. Aqueous humor TAC owns the potential to assess cataracts in an objective and quantitative way.

Total Phenolic Content and Antioxidant and Antimicrobial Activities of Papaver rhoeas L. Organ Extracts Growing in Taounate Region, Morocco.

The objective of this study is to valorize Papaver rhoeas L. from the Taounate region of Morocco by determining the total polyphenol content (TPC), the total flavonoid content (TFC) and the antioxidant and antimicrobial activities of four organs. The quantification of TPC and TFC in root, stem, leaf and flower extracts (RE, SE, LE and FE, respectively) was estimated by the Folin–Ciocalteu reaction and the aluminum trichloride method, respectively. Two tests were used to assess antioxidant power: the DPPH test and TAC assay. The antimicrobial activity was studied against five pathogenic bacteria and yeast, using two methods: disk diffusion and microdilution. The TPC in LE and LF was twice as high as that in RE and SE (24.24 and 22.10 mg GAE/g, respectively). The TFC values in the four extracts were very close and varied between 4.50 mg QE/g in the FE and 4.38 mg QE/g in the RE. The LE and FE showed low DPPH values with IC50 = 0.50 and 0.52 mg/mL, respectively. The TAC measurement revealed the presence of a significant amount of antioxidants in the studied extracts, mainly in LE and FE (6.60 and 5.53 mg AAE/g, respectively). The antimicrobial activity results revealed significant activity on almost all of the tested strains. The MIC of FE and SE against E. coli 57 was 1.56 and 0.78 mg/mL, respectively, while against the S. aureus it was 50 and 25 mg/mL, respectively. The low MLC value (1.56 mg/mL) was recorded against E. coli 57 by RE and SE.