Concentration-dependent Antioxidant Activity Research Articles

Structural characterization, antioxidant activities and physicochemical properties analysis of a galactose-rich exopolysaccharide produced by Limosilactobacillus fermentum YL-11

Lactobacilli-derived exopolysaccharides (EPSs) are widely regarded as safe and have been employed as potential natural, non-toxic additives and functional agents in food industry. The structural properties of a galactose-rich exopolysaccharide produced by Limosilactobacillus fermentum YL-11 (YL-11 EPS) were investigated with chemical and instrumental analysis. The YL-11 EPS was determined to have a molecular weight (Mw) of 13.2 kDa. Nine different types of glycosidic bonds were identified in YL-11 EPS. The inferred structure of the YL-11 EPS contained the backbone of →2)-β-D-Galp-(1→[3)-β-D-Galp-(1]4 → 3)-β-D-Galp-(1 → 3)-β-D-Galp-(1→, with two side chains, β-D-Galp-(1 → 6)-α-D-Manp-(1 → 6)-[α-D-Glcp-1→2]-α-D-Manp-(1 → 3)-[α-D-Glcp-1→6]-α-D-Glcp-(1 → 3)-[α-D-Glcp-1→6]-α-D-Glcp-(1→ with an acetyl group at the O-3 position of →2,6-α-D-Manp-1→ and α-L-Araf-(1→, which were present at the C6 location of the 1,3-β-D-Galp. The YL-11 EPS showed concentration-dependent antioxidant activities and the DPPH, ABTS, hydroxyl groups and superoxide radicals scavenging rates of 10 mg/mL YL-11 EPS reached 61%, 74%, 35.4% and 40%, respectively. The YL-11 EPS also has a beneficial protective impact on H2O2-injured cells, which pretreatment with YL-11 EPS can substantially decrease ROS levels and enhance SOD enzyme activity. Additionally, the YL-11 EPS exhibited good thickening properties and thermal stability. The EPS's structural information and physicochemical properties provide a basis for studying their structure-function relationships.

Polysaccharide fraction from Triplostegia glandulifera Wall and its renoprotective effect in streptozotocin-induced diabetic mice by attenuating oxidative stress

Triplostegia glandulifera Wall (T. glandulifera) is an ethnomedicine commonly used by ethnic minorities in Yunnan, China, to treat kidney disease. However, there are few reports on the renoprotective effects of this substance, and the active ingredients remain unclear. In this study, we extracted the polysaccharide fractions TGB and TGC using the water extraction-alcohol precipitation method and determined their molecular weight (Mw) and monosaccharide composition. The study investigated the protective effects of TGB and TGC fractions against diabetic nephropathy (DN) using an in vitro high glucose-induced HRMCs model and an in vivo STZ-induced diabetic mouse model. HPLC analysis revealed that TGB contained D-galacturonic acid, D-glucose, D-galactose, and D-arabinose, and had a lower Mw than TGC. In vitro, TGB showed concentration-dependent antioxidant activity and effectively reduced abnormal proliferation and while attenuating oxidative stress in HRMCs. In mice with diabetes, TGB corrected the dysregulation of glucose-lipid metabolism and alleviated oxidative stress in the kidneys. Additionally, it improved renal function and reduced renal tissue damage. The study suggests that the low Mw polysaccharides (TGB) have better activity against DN through the antioxidative stress mechanism.Graphical

GC-MS Assisted Determination of 26 Compounds in Phlomis Stewartii Extract Exhibiting Antioxidant, Antifungal, and Antibacterial Properties.

Medicinal plants have long been studied for their therapeutic benifits. The present research aims to unveil complex phytochemical profile and therapeutic properties of ethyl acetate fraction of Phlomis stewartii, an important medicinal plant. In this context, the Gas Chromatography-Mass Spectrometry (GC-MS) analysis of the fraction identified 26 compounds. Additionally, the fraction exhibited concentration dependent antioxidant activity with an IC50 value lower than the standard antioxidant butylated hydroxytoluene. The antifungal activity of the fraction examined against F. oxysporum, A. alternate, and R. solani resulted in almost complete inhibition (>90 %) of fungal growth. Furthermore, the fraction exhibited significant antibacterial potential against B. subtilus, S. aureus, E. coli, and S. dysenteriae, with inhibition zones of 18±0.22, 17±0.22, 12±0.11, and 10±0.12, respectively. Briefly, the plant extract was found to be highly potent, particularly in its antifungal action. Further studies, including natural products isolation coupled with bioassays, are recommended for promising drug candidates discovery.

Phytochemical Analysis, Antioxidant and Anti Hyperlipidemic Activity of Nyctanthes arbor-tristis in Male Wistar Rats

The current study's objective was to assess the antihyperlipidemic, in vitro antioxidant, and qualitative and quantitative phytochemical analysis of Nyctanthes arbor-tristis flowers hydroalcoholic extract at 200 and 400 mg/kg in rats that were made hyperlipidemic by a high-fat diet. The Folins Ciocalteau reagent and the aluminium chloride method were used for the quantitative measurement of flavonoids and phenolics, respectively. Through phytochemical investigation, alkaloids, carbohydrates, glycosides, tannins, phenolic compounds, triterpenoids, and steroids were found in the hydroalcoholic extracts of N. arbor-tristis flowers. The hydroalcoholic extract flowers had a total phenolic content of 126.000 mg/gm, which was followed by flavonoids at 103.104 mg/gm. Hydroalcoholic extracts of flowers showed concentration-dependent antioxidant activity in vitro against DPPH and superoxide radical scavenging test technique. In this investigation, rats were given a high-fat diet as part of an experimental induction procedure. By lowering LDL and VLDL cholesterol levels and raising HDL levels, the HANAT therapy and the medication atorvastatin dramatically reduce body weight. grew When hydroalcoholic flower extracts were given orally to animals that had been forced to become hyperlipidaemic due to a high cholesterol diet, the levels of HDL cholesterol, triglycerides, low density lipoproteins, and very low-density lipoproteins were all much lower. The p value (p<0.001) indicated that the results were significant. The triton-induced study results indicate that animals treated with HANAT at dose levels of 200 mg/kg and 400 mg/kg had considerably lower blood lipid parameters (p<0.01) than the control group; however, the 400 mg/kg of HANAT group animals showed significantly higher serum lipid parameters (p<0.001) than the control group. Additionally, a higher HDL level was noted at this time. Keywords: Nyctanthes arbor-tristis, Physicochemical analysis, Antioxidant activity, DPPH. Antihyperlipidemic activity

Chemical Compositions and In Vitro Antioxidant Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean Cryptomeria japonica (Cupressaceae).

In the Azores archipelago (Portugal), forest operations and wood industry generate large amounts of Cryptomeria japonica biomass residues (CJBR), which can be used to produce valuable essential oils (EOs). In this study, we evaluated the chemical composition and antioxidant activities of EOs from Azorean C. japonica sawdust (CJS) and resin-rich bark (CJRRB). The CJS and CJRRB EOs, obtained via hydrodistillation, showed different yield values (0.27% vs. 0.80% v/w, dry weight) and also different chemical profiles, as assessed using GC/MS. A total of 64 and 85 components were identified in CJS and CJRRB EOs, representing 95.7% and 96.9% of the total composition, respectively. The major components in CJS EO were oxygenated sesquiterpenes (mainly α+β-eudesmol, 1-epicubenol, and cubebol), while in CJRRB EO, the major components were monoterpene hydrocarbons, including α-pinene, δ-3-carene, and limonene (66.6% vs. 6.4% for oxygenated sesquiterpenes and 0% vs. 64% for monoterpene hydrocarbons, respectively). Antioxidant activity was estimated using (i) two radical-based assays, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and (ii) a lipid model assay, β-carotene-linoleic acid bleaching activity (BCBA). Both CJS and CJRRB EOs exhibited concentration-dependent antioxidant activities, and their DPPH, ABTS, and BCBA EC50 values were 1107 vs. 1275 µg/mL, 260 vs. 498 µg/mL, and 1764 vs. 662 µg/mL, respectively. The results indicate that both EOs were able to exert antioxidant activity via different mechanisms of action. Therefore, Azorean CJS and CJRRB may be sustainable sources for antioxidant compounds. This study expands the chemical and biological knowledge of CJBR EOs and, consequently, adds more value to the C. japonica EO industry.

Mitragyna parvifolia as apotential therapeutic agent for lymphatic filariasis.

This study investigates the medicinal potential of Mitragyna parvifolia (M. parvifolia) leaves for the management of Lymphatic filariasis (LF). Phytochemical screening of the methanolic leaf extract revealed the presence of alkaloids, terpenoids, phenols, tannins, and flavonoids. The GC-MS analysis identified 24 phytoconstituents, including the major alkaloid "mitraphylline." Infrared spectroscopy confirmed the presence of various functional groups corresponding to the identified compounds. The extract exhibited significant antibacterial activity against Staphylococcus epidermidis, Bacillus cereus, and Salmonella typhi. In vitro macrofilaricidal screening demonstrated dose-dependent inhibition of worm motility and MTT reduction, indicating its potential as a macrofilaricidal agent. The larvicidal bioassay showed notable effectiveness against Culex quinquifasciatus larvae, with 1% concentration displaying the highest larvicidal activity. Concentration-dependent antioxidant activity was observed using the DPPH assay, with 100µg/ml showing the highest antioxidant potential. The findings suggest the potential of M. parvifolia leaves for LF management, supporting further research to identify active compounds and elucidate their mechanisms of action. The study highlights the plant's diverse bioactive compounds, antibacterial and macrofilaricidal activities, larvicidal efficacy, and significant antioxidant properties. Future investigations, including in vivo experiments and clinical trials, are warranted to validate the safety and efficacy of M. parvifolia as a potential therapeutic agent for LF.

Cell-free fat extract regulates oxidative stress and alleviates Th2-mediated inflammation in atopic dermatitis.

Atopic dermatitis (AD) is a common inflammatory skin disease that significantly affects patients' quality of life. This study aimed to evaluate the therapeutic potential of cell-free fat extract (FE) in AD. In this study, the therapeutic effect of DNCB-induced AD mouse models was investigated. Dermatitis scores and transepidermal water loss (TEWL) were recorded to evaluate the severity of dermatitis. Histological analysis and cytokines measurement were conducted to assess the therapeutic effect. Additionally, the ability of FE to protect cells from ROS-induced damage and its ROS scavenging capacity both in vitro and in vivo were investigated. Furthermore, we performed Th1/2 cell differentiation with and without FE to elucidate the underlying therapeutic mechanism. FE reduced apoptosis and cell death of HaCat cells exposed to oxidative stress. Moreover, FE exhibited concentration-dependent antioxidant activity and scavenged ROS both in vitro and vivo. Treatment with FE alleviated AD symptoms in mice, as evidenced by improved TEWL, restored epidermis thickness, reduced mast cell infiltration, decreased DNA oxidative damage and lower inflammatory cytokines like IFN-γ, IL-4, and IL-13. FE also inhibited the differentiation of Th2 cells in vitro. Our findings indicate that FE regulates oxidative stress and mitigates Th2-mediated inflammation in atopic dermatitis by inhibiting Th2 cell differentiation, suggesting that FE has the potential as a future treatment option for AD.

Structure characterization and protective effect against UVB irradiation of polysaccharides isolated from the plateau plant Gentiana dahurica Fisch

Gentiana dahurica Fisch. (G. dahurica) is one of the legitimate sources of Qinjiao in Traditional Chinese Medicine (TCM) and grows on high-altitude plateaus. Plants develop unique biochemical accumulations to resist plateau conditions, especially the strong UV irradiation. Thus, this study aimed to investigate the polysaccharide of G. dahurica (GDP), its structure and its activity against UVB irradiation. Four GDPs were isolated and two of them were subjected to structural elucidation. The results suggested that GDP-1 has 53.5 % Ara and 30.8 % GalA as its main monosaccharides, with a molecular weight (Mw) of 23 kDa; the GDP-2 has 33.9 % Ara and 48.5 % GalA, with a Mw of 82 kDa. Methylation and NMR spectroscopy analysis revealed that GDP-1 contains →5)-α-Araf-(1 → 5)-α-Araf-(1 → 3,5)-α-Araf-(1 → 3,4)-α-GalpA-(6-OMe)-(1→ as the main chain, the branches of GalA (with esterification), and the terminal Ara; the GDP-2 contains →4)-α-GalpA-(1 → 4)-α-GalpA-(6-OMe)-(1 → 5)-α-Araf-(1 → 3,5)-α-Araf-(1→ as the main chain, the branches of →5)-α-Araf-(1–5)-α-Araf, and the terminal GalA. Both GDP-1 and GDP-2 exhibited concentration-dependent antioxidant activity against DPPH, ABTS and hydroxyl radicals. Moreover, GDPs significantly attenuated the decreases in viability and proliferation of HaCaT cells after UVB irradiation. They can scavenge reactive oxygen species (ROS) and improve the activities of endogenous antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GSH). The potential mechanism explored by flow cytometry assays of cell apoptosis and cell cycle distribution suggested that GDPs exert protective effects against UVB irradiation by reducing ROS and attenuating S phase cell arrest. In brief, the GDP-1 and GDP-2 are α-1,3- and α-1,4- arabinogalacturonan, respectively. The high content of Ara could be attributed to biochemical accumulation in resisting to the plateau environment and to prevent UVB irradiation-related damage in cells. These findings provide insight into authentic medicinal herbs and the development of GDPs in the modern pharmaceutical and cosmetics industry.

Amino-Functionalized Pluronic F127 micelles as a dual drug delivery nanostructure for controlled therapeutics release

Bacterial infection is one of the serious leading causes of hospitalization. The development of a novel dual drug delivery nanostructure based on polymeric micelles is presented here for the treatment of Staphylococcus aureus-associated infections. The nanostructure was composed of quercetin (QC)-encapsulated in the core of F127 micelles (FQ micelles) which was later shell cross-linked using 3-amisinopropyl triethoxysilane (APTES) molecules through condensation reaction. The functionalization of the head groups of FQ micelles with APTES (FQA NPs) facilitated the covalent linkage of vancomycin (Vanc) drug and consequent formation of FQA-Vanc NPs with the hydrodynamic size of 133 nm. FQA-Vanc NPs demonstrated prolong release of QC and Vanc over a period of 168 h. The core–shell structure offered sustainable release of Vanc and QC to the FQA-Vanc NPs during 96 h and 48 h, respectively. The co-administration of Vanc and QC not only enhanced the antibacterial performance of FQA-Vanc NPs, but also induced time and concentration-dependent antioxidant activities. Overall, the Vanc immobilized-FQA NPs together with antibacterial and antioxidant activities could potentially provide a new therapeutic platform for bacterial infection treatment.

Study on Chemical Composition and Biological Activity of Psidium guajava Leaf Extracts.

Guava (Psidium guajava) is a plant widely distributed in tropical and subtropical regions. Its leaves contain a large amount of physiological molecules such as flavonoid, sesquiterpene, triterpenoid, coumarin, alkaloid, and tannin molecules with antioxidative and anti-inflammatory effects. In this study, the use of concentrated P. guajava leaf extract molecules as a functional natural material was evaluated by confirming the extract's antioxidative, antibacterial, tyrosinase activity inhibition, and collagenase activity inhibition effects and its trans-2-nonenal removal ability. As a result of the analysis of the antioxidant and antibacterial components of concentrated P. guajava leaf extract molecules through GC-MS, a large amount of aromatic hydrocarbon molecules were detected. When different concentrations of ethanol were used for extraction, the leaf extract concentrated with 70% ethanol showed the most effective active molecules. As a result of measuring DPPH radical scavenging activity, a concentration-dependent antioxidant activity was confirmed. The antioxidant activity tended to increase when the ethanol content used for extraction was increased. Molecules such as 2,4-di-tert-butylphenol, caryophyllene oxide, and γ-muurolene in P. guajava leaf extract concentrate appeared to have antibacterial activities against S. aureus bacteria known to cause atopy. As ethanol content increased, the inhibitory effect on tyrosinase activity was increased. In addition, when ethanol content was 50%, the concentrated leaf extract was able to remove trans-2-nonenal by 52.4%. As a result of determining the concentrated leaf extract's collagenase inhibition activity, an inhibition rate close to that of ascorbic acid, a positive control, was confirmed. The concentrated guajava leaf extract molecules were confirmed to have whitening and wrinkle-improving functionality. Thus, the P. guajava leaf extract has high potential as a food and natural cosmetic material.

Centella asiatica improves memory and executive function in middle-aged rats by controlling oxidative stress and cholinergic transmission

Ethnopharmacological relevanceCentella asiatica (L.) Urban, is a medicinal herb with rich history of traditional use in Indian subcontinent. This herb has been valued for its diverse range of medicinal properties including memory booster, and also as a folk treatment for skin diseases, wound healing and mild diuretic. Aim of studyAging is a gradual and continuous process of natural decay in the biological systems, including the brain. This work aims to evaluate the effectiveness of ethanolic extract of Centella asiatica (CAE) on age-associated cognitive impairments in rats, as well as the underlying mechanism. Material and methodsRats were allocated into five distinct groups of 5 animals each: Young rats (3 months old rats), middle-aged (m-aged) rats (13–14 months old), and the remaining three groups were comprised of m-aged rats treated with different concentrations of CAE, viz., 150, 300, and 450 mg/kg b. w., orally for 42 days. Y-maze, open field, novel object recognition, and elevated plus maze tests were used to assess animal behavior. The malondialdehyde (MDA), superoxide dismutase (SOD), and acetylcholinesterase (AChE) assays; and H&E staining were done in the rat brain to assess the biochemical and structural changes. CAE was also subjected to HPLC analysis, in vitro antioxidant and anti-cholinergic activity. The active compounds of CAE were docked with AChE and BuChE in molecular docking study. ResultsThe results showed that CAE treatment improves behavioral performance; attenuates the age-associated increase in MDA content, SOD, and AChE activity; and reduces neuronal loss. In vitro study showed that CAE has concentration-dependent antioxidant and anti-AChE activity. Furthermore, the presence of Asiatic acid and Madecassic acid in CAE and their good binding with cholinergic enzymes (in silico) also suggest the anticholinergic effect of CAE. ConclusionThe findings of the current study show that the anticholinergic and antioxidant effects of CAE are attributable to the presence of Asiatic acid and Madecassic acid, which not only provide neuroprotection against age-associated cognitive decline but also reverse it.

Structural Characterization and Antioxidant Activity of β-Glucans from Highland Barley Obtained with Ultrasonic-Microwave-Assisted Extraction.

In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic-microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid-solid ratio, 20 min ultrasonic time, and 480 W microwave intensity, the DPPH radical scavenging activity of HBG reached 25.67%. Two polysaccharide fractions were purified from HBG, namely HBG-1 and HBG-2. Structural characterization indicated that HBG-1 and HBG-2 had similar functional groups, glycosidic linkages, and linear and complex chain conformation. HBG-1 was mainly composed of glucose (98.97%), while HBG-2 primarily consisted of arabinose (38.23%), galactose (22.01%), and xylose (31.60%). The molecular weight of HBG-1 was much smaller than that of HBG-2. Both HBG-1 and HBG-2 exhibited concentration-dependent antioxidant activity, and HBG-1 was more active. This study provided insights into the efficient extraction of HBG and further investigated the structure and antioxidant activities of purified components HBG-1 and HBG-2. Meanwhile, the results of this study imply that HBG has the potential to be an antioxidant in foods and cosmetics.

Exploring marine algae-derived phycocyanin nanoparticles as a safe and effective adjuvant for sunscreen systems

BackgroundUV radiation (UV) exposure risks skin damage and cancer due to DNA damage and oxidative stress. Synthetic chemical sunscreens that protect against UV radiation can have health and environmental concerns. This study explores phycocyanin (PC), a marine algae-derived natural photoprotective compound, and its crosslinked nanoparticles (PCNP) as safe and effective adjuvants for sunscreen systems.MethodsPCNP was synthesized via genipin-crosslinking. PC and PCNP biocompatibility were assessed on mouse embryonic fibroblast cells. ABTS evaluated antioxidant activity, and the UV absorption capacity of PC and PCNP were analyzed. PCNP skin permeability was tested in vitro and in vivo. Gel formulations with PCNP were examined for UV absorption effects.ResultsPCNP showed good biocompatibility, maintaining cell viability above 90% across concentrations. Both PC and PCNP demonstrated concentration-dependent antioxidant activity, efficiently scavenging free radicals. PCNP exhibited enhanced UV absorption in the UVB range compared to PC alone. Skin permeation studies displayed limited PCNP penetration through skin layers. In vivo, absorption assessments indicated PCNP localized mainly in the stratum corneum. PCNP-containing gels displayed improved UV absorption compared to gels without PCNP.ConclusionThis study showcases PCNP’s potential as a natural and safe adjuvant for sunscreen with enhanced UV protection capabilities. PCNP preserved antioxidant activity, displayed limited skin penetration, and enhanced UV absorption. The findings suggest PCNP’s promise as a viable alternative to synthetic sunscreen agents, delivering effective photoprotection while minimizing health and environmental concerns.

Antioxidant and hepatoprotective effects of Solanum villosum leaf extracts against acetaminophen-induced mouse model of hepatotoxicity

Solanum villosum is an indigenous vegetable and ethno-medicine source in Africa. Scientific validation of their medicinal potential is required. The current study aimed to assess the antioxidant and hepatoprotective effects of S. villosum leaf methanol extracts (SVE) against acetaminophen-induced mouse model. The SVE antioxidant activities were evaluated by ferric reducing antioxidant capacity and hydroxyl radical scavenging activities in vitro. Hepatoprotective activities were assessed by automated hematological analysis, chemical analysis and specific biochemical assays of liver homogenates. Mice were orally administered with SVE at 30, 100, 300 and 500 mg/kg body weight. Hepatotoxicity was induced by acetaminophen 300 mg/kg bw intraperitoneally while silymarin 25 mg/kg bw orally was a positive control. The SVE exhibited a clear concentration-dependent antioxidant activity. Subsequently, SVE treatment significantly (P≤0.05) lowered granulocyte count, while there was a significant increase in lymphocyte count in acetaminophen-treated mice. Further, SVE significantly lowered the activities of alanine transaminase, aspartate transaminase, and alkaline phosphatase, but significantly increased γ-glutamyl-transferase activity in treated mice compared to the controls. However, SVE led to insignificant change in total proteins. Additionally, SVE treatment led to a significant rise in superoxide dismutase and glutathione peroxidase activities but, an insignificant change in catalase activity. In conclusion, SVE confers liver protection by oxidative stress prevention, antioxidant enzyme activation, immuno-modulation and hepatic tissue preservation. The results also support indigenous use of S. villosum to protect patients against drug-induced liver damage and enhance immunity. Further, dietary supplements of S. villosum could be an adjunct therapy in acetaminophen-induced hepatotoxicity.

Phytochemical Constituents of Adansonia digitata L. (Baobab) Fruit Pulp from Tekeze Valley, Tigrai, Ethiopia.

Baobab (Adansonia digitata L) is a large tree species growing in semiarid and arid lowlands of Ethiopia and other places. The plant is valued by natives for its contributions as a cash crop and livelihood tree. Previous studies using samples from different countries have documented their phytochemical profiles and nutritional and health benefits. This study explored the phytochemical constituents and biological activities of fruit pulp extracts of baobab collected from Tekeze Valley, Tigrai, Ethiopia. To this end, qualitative phytochemical screening tests, quantitative phytochemical analyses, and gas chromatography-mass spectrometry (GC-MS) analysis were carried out using aqueous extract. Analyses of antioxidant activities were also conducted with aqueous- and methanol-extracts using of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), and hydroxyl (OH) radical scavenging activity assays. The qualitative screening tests showed the presence of flavonoids, phenols, saponins, tannins, and terpenoids. Quantitative analyses of these phytochemicals at 25, 50, and 100 g/mL aqueous extract resulted in 0.0252 to 0.1000% yields. Yields of flavonoids, phenols, and saponins were higher at 50 g/mL extract, while that of tannins and terpenoids were higher at 100 g/mL. GC-MS analysis resulted in 15 predominant compounds including (1,2bis(trimethylsilyl)benzene (13.17%), 2-methyl-7-phenylindole (11.75%), 2-ethylacridine (10.11%), and benz[b]-1,4-oxazepine-4(5H)-thione,2,3-dihydro-2,8-dimethyl (10.11%). Aqueous and methanol extracts showed concentration-dependent antioxidant activities. In all the assays and concentrations, the antioxidant activities of both extracts were lower than that of the ascorbic acid standard. At equal extract concentrations (e.g., 100 and 250 μg/mL), methanol extract had higher antioxidant activities than aqueous extract. The findings can encourage future initiatives towards large-scale research for compiling a complete phytochemical profile of the fruit pulp of the Ethiopian baobab.

Assessment of antioxidant activity of pure graphene oxide (GO) and composite V2O5/GO using DPPH radical and H2O2 scavenging assays

In this research, the Co precipitation method was utilized to synthesize a nanocomposite of vanadium oxide (V2O5) and graphene oxide (GO). Pure GO was synthesized by the modified hammers method. Using a 1:2 ratio of GO and V2O5 and heating in the oven at 70 °C leading to the formation of V2O5/GO nanocomposite. By grafting of GO on V2O5 surface, a high range of graphene oxidation in V2O5/GO allowed for better reduction with V2O5 metal-oxide. The scanning electron microscope (SEM) images and X-ray diffraction (XRD) spectra provide evidence of the distinct phase of graphene oxide formation. The antioxidant activity of V2O5/GO nanocomposite was conducted in two vitro assays, focusing on neutralization of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2 radicals. The uniqueness of the nanocomposite was evident from its concentration-dependent antioxidant activities. Interestingly, the V2O5/GO samples has showed 60% antioxidant performance in the H2O2 assays compared to its constituent.

Exploration and Evaluation of In-vitro Antioxidant Activity of ABANA: A Polyherbal Formulation

Objective: The purpose of this study was to determine the antioxidant capacity of Abana® (a poly-ingredient formulation with natural constituents). Methods: Extensive ethanol extraction of polyherbal formulations was followed by fractionation into petroleum ether, chloroform, and ethyl acetate extracts. Various fractions were further analyzed using this conventional method for phytochemical composition and concentration dependent antioxidant activity. Due to the presence of phenolic compounds in the formulation, extracts were analyzed for total phenolic content, flavonoid content, and in- vitro antioxidant activity. Antioxidant capacity was determined using total reducing potential, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azinobis-ethyl-benzothiozoline-sulphonic acid diammonium salt (ABTS) and nitric oxide inhibition assays. Results: Primitive phytochemical screening revealed the presence of steroids, saponins, flavonoids, alkaloids and tannins which were confirmed using thin-layer chromatography. The antioxidant activity of Abana tablet extracts decreased in the order ethyl acetate > ethanolic > chloroform > petroleum ether comparable to that of ascorbic acid and butylated hydroxytoluene. Conclusion: The current investigation suggests that the ethanolic extract and fractions of Abana polyherbal formulations exhibit significant antioxidant activity. Our results strongly imply that polyherbal compounds are a potential source of antioxidants capable of scavenging free radicals. The strong positive connection between antiradical scavenging activity and overall polyphenolic concentration in polyherbal drugs demonstrates that polyphenols are significant components capable of scavenging free radicals. Additional research is required to isolate and characterize the active moiety responsible for biological activity and treat it under various stress conditions.

Effect of Oil Pollution on the Antioxidant Activity of the Methanolic Extracts of Polluted and Unpolluted Leaves of Hyptis suaveolens (L)

Hyptis suaveolens (L.) Poit, an aromatic weed known as pignut or daddoya-ta-daji in the Hausa language, has a longstanding history of usage as food and medicine in Kaduna state. This plant is interestingly found thriving in environments with or without oil pollution. In our modern industrial society, it's practically inevitable that these medicinal plants come in contact with oil contamination. This is largely because oil pipelines, often aged and susceptible to corrosion or illicit activities leading to leakages, are scattered across urban and rural settlements, influencing the plants' phytochemical composition. This study is focused on examining if oil pollution alters the antioxidant activity of this plant. An evaluation of the antioxidant properties of methanol extracts from Hyptis suaveolens (L.) leaves, both from polluted and unpolluted areas, was carried out using the 2,2-Diphenyl-1-Picrylhydrazyl-hydrate (DPPH) free radical scavenging assay. The outcomes showed that the extracts have significant (p < 0.05) concentration-dependent antioxidant activity. Yet, the unpolluted H. suaveolens leaves' methanol extract exhibited superior DPPH radical scavenging action compared to the extract from the polluted leaves. The median inhibitory concentrations (IC50) for the polluted and unpolluted leaves' methanol extracts were 35 µg/ml and 20 µg/ml respectively. Therefore, the contamination had a detrimental impact on the plant extract's antioxidant capacity.

In vivo antioxidant activity of rabbiteye blueberry (Vaccinium ashei cv. 'Brightwell') anthocyanin extracts.

Blueberries are rich in phenolic compounds including anthocyanins which are closely related to biological health functions. The purpose of this study was to investigate the antioxidant activity of blueberry anthocyanins extracted from 'Brightwell' rabbiteye blueberries in mice. After one week of adaptation, C57BL/6J healthy male mice were divided into different groups that were administered with 100, 400, or 800 mg/kg blueberry anthocyanin extract (BAE), and sacrificed at different time points (0.1, 0.5, 1, 2, 4, 8, or 12 h). The plasma, eyeball, intestine, liver, and adipose tissues were collected to compare their antioxidant activity, including total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity and glutathione-peroxidase (GSH-PX/GPX) content, and the oxidative stress marker malondialdehyde (MDA) level. The results showed that blueberry anthocyanins had positive concentration-dependent antioxidant activity in vivo. The greater the concentration of BAE, the higher the T-AOC value, but the lower the MDA level. The enzyme activity of SOD, the content of GSH-PX, and messenger RNA (mRNA) levels of Cu,Zn-SOD, Mn-SOD, and GPX all confirmed that BAE played an antioxidant role after digestion in mice by improving their antioxidant defense. The in vivo antioxidant activity of BAE indicated that blueberry anthocyanins could be developed into functional foods or nutraceuticals with the aim of preventing or treating oxidative stress-related diseases.

THE INFLUENCE OF CATHARANTHUS ROSEUS (L.) G. DON. ETHANOL EXTRACT IN CLOVE OIL NANOEMULSION: PHYSICAL CHARACTERIZATION, ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES

Objective: This study aimed to develop a topical nanoemulsion using clove oil and ethanol extract of catharanthus roseus (L.) G. for antioxidant and antibacterial dosage form. Methods: The nanoemulsion was produced using a spontaneous emulsification method. The formulation was carried out using tween 80 and pluronic 127 as surfactants with different extract concentrations (0.5–2%). The characterizations of the formula included organoleptic test, homogeneity, pH determination, emulsion type, viscosity, particle size determination, zeta potential, and stability test were evaluated. Antioxidant activity was conducted using DPPH method and antibacterial activity was determined against propionibacterium acnes and Staphylococcus epidermidis. Results: The result showed that all the formulations produced a stable nanoemulsion with semisolid, clarity, transparent and homogenous characteristic. The nanoemulsion had pH of 5.5-6.5 and belong to oil in water (O/W) type of emulsion. The formula showed viscosity ranged from 121.33±0.29 until 211.01±1.00 cps, had particle size below than 300 nm, and were stable for 3 mo of storage and after accelerated evaluation. nanoemulsion contained 2% of c. roseus extract showed moderate antioxidant activity with IC50 value of 96.29±3.64 and antibacterial activity with 10.65±0.15 and 13.27±0.21 mm of inhibition zones for propionibacterium acnes and Staphylococcus epidermidis, respectively. Conclusion: Clove oil combined with the ethanol extract of c. roseus produced a stable nanoemulsion, which demonstrated concentration-dependent antioxidant and antibacterial activities.