Hydroxyl Radical Scavenging Assay Research Articles

Senna petersiana inhibits key digestive enzymes and modulates dysfunctional enzyme activities in oxidative pancreatic injury

Objective: To evaluate the effect of Senna petersiana leaf extracts on key digestive enzymes and FeSO4-induced oxidative injury. Methods: Dried Senna petersiana leaf powder (60 g) was defatted in n-hexane and then extracted sequentially at room temperature with dichloromethane, methanol, and distilled water. The total phytochemical content of the extracts was estimated using established methods. The in vitro antioxidant, anti-lipase, and antidiabetic activities and the effect of the extracts on intestinal glucose absorption and FeSO4-induced pancreatic oxidative injury were determined using different protocols. Moreover, GC-MS analysis was performed to identify the main compounds of the plant extract. Molecular docking analysis was also carried out to evaluate the binding energy of compounds with digestive enzymes. Results: Senna petersiana leaf extracts showed significant antioxidant activities in FRAP, DPPH, and hydroxyl radical scavenging assays. They also inhibited pancreatic lipase and lowered intestinal glucose absorption by suppressing activities of α-amylase and α-glucosidase. Treatment with the extracts also lowered lipid peroxidation (malondialdehyde), nitric oxide level, acetylcholinesterase, and ATPase activities with simultaneous improvement of antioxidant (catalase, superoxide dismutase, glutathione) capacity in the type 2 diabetes model of oxidative pancreatic injury. GC-MS characterization of the extracts revealed the presence of stilbenoids, alkaloids, and other compounds. Molecular docking screening assay indicated the extract phytochemicals showed strong interaction with the active site amino acids of the targeted digestive enzymes. Among the Senna petersiana compounds, veratramine had the highest affinity for α-amylase and lipase, whereas dihydrostilbestrol was most attracted to α-glucosidase. Conclusions: Senna petersiana inhibits carbohydrate digestive enzymes, reduces intestinal glucose absorption, and exerts ameliorative effects on FeSO4-induced oxidative pancreatic injury with significant antioxidant capabilities. Detailed in vivo studies are underway to understand the plant's therapeutic potential in diabetes management.

Bio-guided Studies of Lotus maritimus Aerial Parts and Investigation of their Antioxidant, Tyrosinase and Elastase Inhibitory Activities

Background: Lotus maritimus L. (Fabaceae) is a perennial herb species with yellow flowers, growing in Europe, Asia, Middle East and Maghreb. Some flavones and flavonols have been identified in their leaves and flowers. Their leaf extract was used as a cellulolytic and antiaging cosmetic ingredient. Objective: The aim of this work was to perform antioxidant, anti-tyrosinase and anti-elastase properties of L. maritimus aerial parts and their chemical profile. Methods: A 13C NMR-based dereplication method combined with a bio-guided purification was used for metabolite identification. Chemical structures were determined by NMR and ESI-MS spectroscopic methods. The antioxidant properties of the fractions and purified compounds were measured using CUPRAC, DPPH and hydroxyl radical scavenging assays. Their inhibitory activities against the fungal tyrosinase and human neutrophil elastase enzymes were also evaluated. Results: EtOAc and n-BF fractions were characterized as the most active parts. Twenty-two compounds were identified from these fractions by using a 13C NMR-based dereplication method. This process was completed by the purification of minor compounds in the n-BuOH fraction. Eight known compounds were isolated, including many mono-glycosylated flavonoids with variable substitutions on the B-ring, allowing structure-activity relationships. Conclusion: Twenty-two compounds, including phenolic acids, flavonoids and glycoside derivatives, were firstly described in L. maritimus. Three quercetin and myricetin-type flavonoids exhibited good antioxidant activities and all flavonoids tested have moderate effects on elastase inhibition.

Formulation of plant-based yoghurt from soybean and quinoa and evaluation of physicochemical, rheological, sensory and functional properties

The aim of this study was to develop a novel plant-based yoghurt with high sensory acceptance and nutrition value. Soybean and quinoa were used as the substrates, and all formulations with different substrate ratios were inoculated with lactic acid bacteria (LAB). Fermentation modified the proximate composition, and a higher content of soybean accentuated the growth of LAB. Formulated yoghurts presented a weak post-acidification, and the viability of LAB was higher than 106−7 CFU/g during a 21 days storage. Quinoa addition significantly improved the water holding capacity (WHC) and decreased the yellowness, and an increase of lightness and a decrease of WHC occurred during the storage. Compared with the plain substrate yoghurt, mixed formulation had no significant impact on textual parameters, whereas increased the liking scores in sensory evaluation. Furthermore, fermentation improved the total phenolic content (TPC), which showed a dose-dependent relationship between soybean content. Results obtained from DPPH, ABTS, hydroxyl radical scavenging assay, FRAP assay, and α-amylase, α-glucosidase and pancreatic lipase inhibition assay showed that fermentation enhanced the antioxidant capacities and digestive enzyme inhibitory activities. TPC increase and phenolic biotransformation may explain the enhancement of the nutritive values. Based on the sensory and function evaluation, the ratio of quinoa against soybean at 8:2 and 2:8 presented the best formulations.

Anticancer, antioxidant, and antimicrobial properties of solvent extract of Lobophora variegata through in vitro and in silico studies with major phytoconstituents

Seaweeds possess a wide range of bioactive compounds which have been play a vital role in production of novel pharmaceutical and nutraceutical products resources. The present study employed in silico molecular docking to characterize the biomedical potential of brown seaweed Lobophora variegata through antibacterial, antibiofilm, antioxidant and anticancer activities. The antibacterial activity of L. variegata extracts was analyzed against Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa strains producing biofilms. The antioxidant activity was assessed using (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), superoxide, and hydroxyl radical scavenging assays. Further, the anticancer, antibacterial, and antioxidant activities of the bioactive compounds were evaluated through molecular docking using GLIDE ligand docking module and prime MM-GBSA module in the Schrodinger software. The phytochemical analysis of the methanolic extract of L. variegata found more phycocompounds which was confirmed by FT-IR and GC-MS. The significant level of phenol and flavonoid were expressed in methanolic extract of L. variegata. In addition, the potent antioxidant activity of the methanolic extract was efficiently expressed during the free radical scavenging assays of ABTS, hydroxyl, and superoxide denoted as 34.94, 26.64, and 29.86 mg/g, respectively. The antibacterial and biofilm activities of the methanolic extract of L. variegata had significant results. Moreover, the methanolic extract exhibited cytotoxicity against human colon cancer HT-29 cell lines at an inhibitory concentration is 193.65 μg/mL. Through the computational analysis, glyceryl monostearate, 2-palmitoylglycerol, phthalic acid, 2-chloropropyl ethyl ester, phthalic acid, 5-methylhex-2-yl ethyl ester, and l-(+)-ascorbic acid 2,6-dihexadecanoate results as top ranked molecules and shown to be a promising compounds, which were evaluated for anticancer, antioxidant, and antibacterial properties against multi-target proteins. Based on the experimental results, L. variegata could be a valuable marine source for developing novel pharmaceutical applications.

Biogenic synthesis of zinc oxide nanoparticles using mushroom fungus Cordyceps militaris: Characterization and mechanistic insights of therapeutic investigation

The present research demonstrates the Cordyceps militaris (a medicinal mushroom) mediated fabrication of zinc oxide nanoparticles (Cor-ZnONPs) and its therapeutic investigation. The biosynthesized Cor-ZnONPs were characterized by UV–Visible spectroscopy, FT-IR, XRD, SEM with EDX, HRTEM, particle size, and zeta potential analysis and evaluated for their antidiabetic, antioxidant, and antibacterial potential by in-vitro methods. The nanoparticles showed SPR peak at 354 nm. FT-IR analysis exhibited a sharp peak at 432.05 cm−1, demonstrating the distinctive Zn–O bond. Cor-ZnONPs had an average particle size of 1.83 nm with a polydispersity index of 0.29 and were crystalline as obtained from XRD analysis. Zeta potential of −6.42 mV indicates the moderate stability of nanoparticles. EDX analysis confirmed the presence of Zinc and Oxygen. Cor-ZnONPs expressed a 70–90% survival rate in brine shrimp lethality assay with 10–100 ppm concentrations and exhibited potent α-amylase and α-glucosidase inhibitory effect with an IC50 of 46.29 ± 0.49 and 47.21 ± 0.19 μg/mL, respectively. Cor-ZnONPs showed moderate radical potency with DPPH, ABTS, hydroxyl radical, nitric oxide, and superoxide radical scavenging assays. Cor-ZnONPs revealed the highest antibacterial activity against Pseudomonas aeruginosa, followed by Shigella flexneri, Proteus vulgaris, and Rhodococcus equi. Moreover, a very low concentration of Cor-ZnONPs was required to inhibit the growth of studied bacterial strains. This study provides an informational insight into the Cordyceps militaris mediated synthesis of ZnONPs, and their antidiabetic, antioxidant, and antibacterial potential. Biosynthesized Cor-ZnONPs indicate a new application of nanoparticles in the development of therapeutic drugs.

Radical scavenging potency, HPLC profiling and phylogenetic analysis of endophytic fungi isolated from selected medicinal plants of Saudi Arabia

BackgroundEndophytic fungi are associated within plant tissues without any harmful effects. They produce a diversity of metabolites and are well known as rich source of bioactive substances. This study aimed to identify fungal isolates from different medicinal plants, evaluate their antioxidant potency and detect components responsible for antioxidant activity. ResultsIn the present investigation, 4 endophytic fungal isolates were obtained from different medicinal plants Rumex nervosus, Pulicaria crispa and Withania somnifera. Those isolates were characterized as Penicilluim commune, Penicilluim glaucoroseum, Aspergillus flavipes and Fusarium chlamydosporum according to morphological and phylogenetic bases. These strains were propagated on humified rice and their crude ethyl acetate extracts were assayed for their total phenols, flavonoids and antioxidant potency against DPPH free radicals. The results showed that the elevated constituent of phenolics was found in P. commune (148.24 mg/g), followed by F. chlamydosporum (124.25 mg/g), while the highest total flavonoids were determined in A. flavipes, followed by F. chlamydosporum, P. glaucoroseum, P. commune, respectively. Moreover, the maximum hydroxyl radical-scavenging assay was IC50 = 2.13 mg/mL exhibited by P. commune, followed by F. chlamydosporum (2.68 mg/mL). Weak antimicrobial and cytotoxic effects were reported by the studied strains against pathogenic isolates and (HepG2) hepatocellular carcinoma cell line. The fungal EtOAc extracts were characterized quantitatively by the incidence of different phenols, flavonoids, and phenolic acids, as detected by HPLC. ConclusionsEndophytic fungi derived from medicinal plants are a promising candidate for the wide industrial production of antioxidant agents with several useful medical and pharmaceutical applications.How to cite: Hassane A. M. A, Taha T. M, Awad M. F, et al. Radical scavenging potency, HPLC profiling and phylogenetic analysis of endophytic fungi isolated from selected medicinal plants of Saudi Arabia. Electron J Biotechnol 2022;58. https://doi.org/10.1016/j.ejbt.2022.05.001

Phytochemical analysis and preclinical toxicological, antioxidant, and anti-inflammatory evaluation of hydroethanol extract from the roots of Harpalyce brasiliana Benth (Leguminosae)

Ethnopharmacological relevanceHarpalyce brasiliana Benth (Leguminosae) is a shrub endemic to Brazil, popularly known as “snake's root.” This species is used in folk medicine for the treatment of inflammation and snakebites. However, up to now there is no scientific research to justify its popular use. The study aimed to characterize the phytochemical profile of the hydroethanol extract from the roots of H. brasiliana (Hb), to evaluate its antioxidant and anti-inflammatory potential, as well as to investigate its cytotoxicity and acute toxicity. Materials and methodsThe extract was obtained by maceration method using a solution of ethanol:water (70: 30, v/v). The phytochemical profile was obtained by liquid chromatography coupled to mass spectrometry. The cytotoxicity of extract (31–2000 μg/mL) was evaluated in vitro, by the 3-methyl-[4-5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method using murine macrophage and fibroblast cell lines (RAW 247.6 and 3T3, respectively) and by the hemolytic assay. For the in vivo acute toxicity, the extract (2000 mg/kg) was administered and after 14 days the weight (body and organs) and hematological and biochemical parameters were analyzed. Chemical free radical scavenging effect of the extract (125–2000 μg/mL) was investigated through diphenylpicryl hydrazine reduction, total antioxidant capacity, reducing power, hydroxyl radical scavenging, and iron and copper chelating assays. In vitro anti-inflammatory effect of the extract (125, 500, and 2000 μg/mL) was demonstrated through of nitric oxide (NO) analyzed in lipopolysaccharides stimulated RAW 264.7 cells. In vivo anti-inflammatory activities were evaluated in carrageenan-induced paw edema and zymosan-air-pouch models, with gavage administration (post-treatment) of extract at 100, 200, and 400 mg/kg. For the first animal model, the anti-edematogenic activity and myeloperoxidase (MPO) levels were investigated, while in the zymosan-air-pouch model the leukocyte number, MPO, total protein and pro-inflammatory cytokine (IL-1β, IL-6, and TNF-α) levels were quantified. In addition, the oxidative parameters such as malondialdehyde (MDA) and reduced glutathione (GSH) were determined. ResultsThe phytochemical profile revealed the presence of 20 compounds, mainly prenylated and geranylated pterocarpans. The extract demonstrated no cytotoxicity in erythrocytes, macrophages and fibroblasts cells at the tested concentrations, as well as no sign of toxicity and mortality or significant alterations on the hematological and biochemical parameters in the acute toxicity model. The extract was also able to neutralize chemical free radicals, with copper and iron chelating effect. For the NO dosage, the extract evidenced the reduction of expression of NO after the administration of the extract (500 and 2000 μg/mL). The edematogenic model revealed a decrease in paw edema and MPO level, while the zymosan-air-pouch model evidenced a reduction of leukocyte number (especially of polymorphornuclears), MPO production, and total protein and cytokine levels, and demonstrated the antioxidant effect through a decrease in MDA and increase in GSH parameters. ConclusionThis approach demonstrates for the first time that Hb is not cytotoxic, has low acute toxicity, and possesses antioxidant and anti-inflammatory properties in preclinical analyses, corroborating its popular use.

Phytochemical analysis by UPLC-QTOF-MS/MS and evaluation of antioxidant and anti-inflammatory activities of the extract and fractions from flowers of Cochlospermum vitifolium

Cochlospermum vitifolium (pacotê) is a medicinal plant used for treatment of hypertension, hepatitis, jaundice, hyperglycemia and inflammatory disorders. This study aimed to identify compounds present in ethanolic extract (EtOH) and hexane (Hex), ethyl acetate (EtOAc) and methanol/water (MeOH) fractions from C. vitifolium flowers and evaluate the antioxidant and anti-inflammatory potential. The phenolic compounds were characterized by UPLC-QTOF-MS/MS and 22 compounds were identified. The antioxidants effect of EtOH, Hex, EtOAc and MeOH fraction were investigated through quantification of total phenolic, diphenylpicryl hydrazine reduction, total antioxidant capacity, iron and cooper-chelating, reducing power, superoxide and hydroxyl radical scavenging assays. The anti-inflammatory potential of EtOH and EtOAc fraction (intra-gastric gavage route, 50, 100 or 150 mg/kg) were assayed by carrageenan-induced paw edema and zymosan-induced air pouch models. The EtOH and EtOAc fraction revealed higher concentration of phenolic compounds and antioxidant action when compared with Hex and MeOH fractions. The extract and fractions showed specific copper chelating effect. The EtOH and EtOAc fraction demonstrated be effective reducing the edema in carrageenan-induced paw edema model. In zymosan-induced air pouch model, the extract and fraction were able to decrease the leukocytes cells, proteins total and cytokines (IL-1β and IL-6) levels. This is the first study that demonstrated the antioxidant and anti-inflammatory effect of EtOH and EtOAc fraction of C. vitifolium flowers, suggesting that its phenolic compounds are, at least in part, responsible for anti-inflammatory effects.

Phytochemical Characterization and in vitro Antioxidant, in vitro Antidiabetic Activity of Manilkara hexandra Seed Extract

Manilkara hexandra (Roxb.) Dubard is a large evergreen tree species widely distributed throughout India and other countries and belongs to family Sapotaceae. Conventionally, the entire plant has been used for the treatment of various diseases. The present study has been carried out for identification of its bioactive constituents by high resolution-liquid chromatography-quadrupole-time-of-flight-mass spectrometry (HR-LC-QTOF-MS) and evaluation of in vitro antioxidant and in vitro antidiabetic activity of the methanolic extract of the seeds of the plant. Twenty-eight bioactive compounds from the methanolic extract of Manilkara hexandra seeds (MEMH) were identified using HR-LC-QTOF-MS. In vitro antioxidant activity of MEMH was evaluated using 1,1-diphenyl-2-picryl-hydrazyl, nitric oxide, superoxide, and hydroxyl radical scavenging assays and the IC50 values for MEMH were found to be similar to standard drug. In vitro antidiabetic activity was also evaluated using anti α-amylase and anti-α-glucosidase assays and the IC50 values for MEMH were found to be good as compare to standard drugs. The compounds identified by HR-LC-MS partly explain the various therapeutic effects of the seeds of the plant. Thus, it can be concluded that MEMH is rich in bioactive phytochemicals and possesses potential antidiabetic and antioxidant activity.

The Influence of Synthesis Conditions on the Antioxidant Activity of Selenium Nanoparticles.

Selenium nanoparticles (SeNPs) have attracted great attention in recent years due to their unique properties and potential bioactivities. While the production of SeNPs has been long reported, there is little news about the influence of reaction conditions and clean-up procedure on their physical properties (e.g., shape, size) as well as their antioxidant activity. This study takes up this issue. SeNPs were synthesized by two methods using cysteine and ascorbic acid as selenium reductants. The reactions were performed with and without the use of polyvinyl alcohol as a stabilizer. After the synthesis, SeNPs were cleaned using various procedures. The antioxidant properties of the obtained SeNPs were investigated using DPPH and hydroxyl radical scavenging assays. It was found that their antioxidant activity does not always depend only on the nanoparticles size but also on their homogeneity. Moreover, the size and morphology of selenium nanoparticles are controlled by the clean-up step.

Antimicrobial Potential of Zinc Oxide Nanoparticles from Marine Macroalgae

Abstract: The current study evaluates the free antimicrobial and radical scavenging properties of zinc oxide nanoparticles(ZnONP’s) synthesized from an aqueous extract of Sargassum polycystum brown algae. The free radical scavenging potential of ZnO nanoparticles was evaluated through DPPH, Nitric oxide, Hydroxyl radical and Hydrogen peroxide scavenging assays. In addition to that, the antibacterial and antifungal activity of synthesized ZnO nanoparticles was examined against different species. The free radical scavenging and antimicrobial potential of these Sargassum polycystum ZnO nanoparticles were associated with their phenolic compounds. ZnO- NP’s DPPH radical reducing potential was found to be 12.45 ± 0.19μg/mL, Nitric oxide at 0.68±0.04 μg/ml, Hydrogen peroxide to be 0.39±0.01 μg/ml and Hydroxyl radical scavenging potential with 0.63±0.04 μg/ml. Furthermore, ZnO- NP’s antimicrobial efficacy showed significant results against Staphylococcus aureus, Escherichia coli, Salmonella typhi, Klebsiella pneumonia and fungal strains of A. niger Candida albicans. Further research is on purifying the selected phenolic compounds and developing their acuteness for specificity for ultimate pharmaceutical use. Keywords: Marine algae, ZnO nanoparticles, antioxidant and antimicrobial activity, Gulf of Mannar.

Effect of pH value and the distance between the electrodes on physicochemical properties of chitosan under SPP treatment

Solution plasma process (SPP) was employed to degrade chitosan. The effects of the initial pH value and the distance between the electrodes on the steady shear flow behavior, structural characterization, molecular conformation, and antioxidant activity of chitosan were investigated. The results revealed that a lower initial pH value and a narrower distance between the electrodes were beneficial to the decrease in viscosity and increase in shear-thinning capacity. Structural characterization of the chitosan by FT-IR and 1H NMR showed that chemical structure of chitosan was not destroyed at different process parameters. The results of XRD, HPSEC-MALLS, SEM, and AFM indicated that SPP degradation clearly decreased the crystallinity, molecular weight, molecular size, and molecular aggregation of chitosan. At initial pH values of 2.8 and 5.8, the molecular weight was 27.16 and 44.25 kDa, at the distance between the electrodes of 4 and 8 mm, it was 35.88 and 66.17 kDa, respectively. The results of DPPH and hydroxyl radical scavenging assays demonstrated that a lower initial pH value and a narrower distance between the electrodes enhanced the antioxidant activity.

Exploring Dose-Dependent Cytotoxicity Profile of Gracilaria edulis-Mediated Green Synthesized Silver Nanoparticles against MDA-MB-231 Breast Carcinoma.

Green-based synthesis of metal nanoparticles using marine seaweeds is a rapidly growing technology that is finding a variety of new applications. In the present study, the aqueous extract of a marine seaweed, Gracilaria edulis, was employed for the synthesis of metallic nanoparticles without using any reducing and stabilizing chemical agents. The visual color change and validation through UV-Vis spectroscopy provided an initial confirmation regarding the Gracilaria edulis-mediated green synthesized silver nanoparticles. The dynamic light scattering studies and high-resolution transmission electron microscopy pictographs exhibited that the synthesized Gracilaria edulis-derived silver nanoparticles were roughly spherical in shape having an average size of 62.72 ± 0.25 nm and surface zeta potential of -15.6 ± 6.73 mV. The structural motifs and chemically functional groups associated with the Gracilaria edulis-derived silver nanoparticles were observed through X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy. Further, the synthesized nanoparticles were further screened for their antioxidant properties through DPPH, hydroxyl radical, ABTS, and nitric oxide radical scavenging assays. The phycosynthesized nanoparticles exhibited dose-dependent cytotoxicity against MDA-MB-231 breast carcinoma cells having IC50 value of 344.27 ± 2.56 μg/mL. Additionally, the nanoparticles also exhibited zone of inhibition against pathogenic strains of Bacillus licheniformis (MTCC 7425), Salmonella typhimurium (MTCC 3216), Vibrio cholerae (MTCC 3904), Escherichia coli (MTCC 1098), Staphylococcus epidermidis (MTCC 3615), and Shigella dysenteriae (MTCC9543). Hence, this investigation explores the reducing and stabilizing capabilities of marine sea weed Gracilaria edulis for synthesizing silver nanoparticles in a cost-effective approach with potential anticancer and antimicrobial activity. The nanoparticles synthesized through green method may be explored for their potential utility in food preservative film industry, biomedical, and pharmaceutical industries.

Antioxidant activity assessment of Yingjisha sweet almond oil

SummarySweet almond is one of the main cash crops in Yingjisha, Xinjiang Autonomous Region, China. The composition of sweet almond oil (SAO) was analysed by gas chromatography‐mass spectrometry (GC‐MS). SAO’s antioxidant activities were investigated by measuring its scavenging ability with 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), 2,2′‐Azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS), hydroxyl radical scavenging assay and 6‐hydroxy‐2,5,7,8‐tetramethylchroman‐2‐carboxylic acid (Trolox) equivalent antioxidant capacity (TEAC) assay. Furthermore, in vivo antioxidant capacity was assessed using Saccharomyces cerevisiae model stimulated by hydrogen peroxide (H2O2) and carbon tetrachloride (CCl4). The results showed that SAO was mainly composed of methyl oleate (21.28%), methyl stearate (18.55%) and methyl palmitate (14.1%). In vitro antioxidant test results showed that compared with the scavenging three free radicals capacity of 1 mmol L−1 Trolox, the SAO needed to reach 5 mg mL−1, 20 mg mL−1 and less than 20 mg mL−1, respectively. In vivo experiments showed that SAO rescued the survival and inhibited intracellular oxidation and lipid peroxidation of Saccharomyces cerevisiae exposed to H2O2 and CCl4. Additionally, our results showed that the catalase encoded by the Gsh1 gene may be involved in the mechanism of action of SAO against intracellular oxidation. These findings suggest that SAO possesses antioxidant capacities, and it is recommended to develop dietary antioxidants based on SAO.

Synthesis, in silico ADME, toxicity prediction and molecular docking studies of N-substituted [1,2,4]triazolo[4,3-a]pyrazine derivatives as potential anticonvulsant agents

Two new series of N-substituted [1,2,4]triazolo[4,3-a]pyrazine derivatives, 2a-e and 3a-e were synthesized by coupling substituted acid chlorides/benzyl chlorides with 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine and investigated for antioxidant, anticonvulsant effect and neurotoxicity. The in vitro antioxidant activity was assessed using the DPPH and hydroxyl radical scavenging assays. The anticonvulsant potential of the synthesised molecules was assessed using MES and PTZ tests, and their neurotoxicity was evaluated using a rotorod test in mice. Compounds 2a, 2b, 2e, and 3d were identified to have a good anti-seizure action while causing minimal neurotoxicity. The most effective anticonvulsants were compounds 2a, 2b, and 2e, with median effective dosages of 0.38, 0.36, and 0.25 mg/kg, respectively. A computational analysis was also conducted, which included drug-likeness and docking studies, as well as prediction of pharmacokinetic parameters. Docking studies of potent compounds in the binding pocket of the 4-aminobutyrate aminotransferase protein (PDB ID: 1OHV) reveal strong binding interactions and high docking scores. From these findings, the potent compounds 2a, 2b, and 2e might be a promising lead in the quest for safer and more effective anticonvulsants with neuroprotective properties.

Hepatoprotective activity of andrographolide possibly through antioxidative defense mechanism in Sprague-Dawley rats

The aims of this study to assess the efficiency of AGL against acetaminophen (APAP)-induced hepatic toxicity that was generated by mitochondrial oxidative stress and glutathione depletion. Free radical scavenging potentiality was analyzed by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide, nitric oxide, and hydroxyl radical scavenging assays. APAP-induced liver toxicity was formed at a dose level of 640 mg/kg mg/kg BW each, p.o. for 14 days for all experimental rats except the vehicle control group. AGL (5 and 10 mg/kg) were treated orally with negative control and negative control silymarin (50 mg/kg) group. To assess the protective effect, we looked at the levels of serum biochemical markers, liver histoarchitecture, and hepatic antioxidant enzyme activity. AGL showed in vitro anti-oxidant potentialities by scavenging radicals in the respective assays. As evidenced by serum biochemical indicators and relative liver weight, AGL co-administration substantially reduced toxicant-induced hepatic damage. APAP-intoxication increased the malondialdehyde (MDA) level and declined in cellular endogenous antioxidant enzymes such as reduced catalase, superoxide dismutase, and glutathione, where, AGL treatment amended their level. In the same way, histopathological evaluation further verified that AGL protected the hepatocyte from APAP-induced damage. As AGL scavenges toxic free radicals, thereby protects mitochondria and other organelles from reactive oxygen and nitrogen species-mediated stress and its eventual consequence necrosis. Therefore, we propose the hepatoprotective activity of AGL through its antioxidant mechanism.

Assessment of In Vitro Antioxidant, Antipsoriatic and Anticancer Activity of Methanolic Extract of Nigella sativa Seeds

Psoriasis is a chronic inflammatory skin disease with immense physical, biological and psychological implications which puts a person at high risk for developing cancers like lung cancer. The aim of the study was to determine the effectiveness of Nigella sativa seeds as an effective antioxidant that can prevent the proliferation of psoriatic epidermal keratinocytes and lung cancer cells. Quantitative determination of phenols, flavonoids and antioxidant activities were performed using Folin-Ciocalteu colorimetric method, aluminium chloride colorimetric method and hydroxyl radical scavenging assay respectively. In vitro antiproliferative assay against psoriatic epidermal keratinocytes and A549 human lung cancer cell lines were determined using 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide assay. Nigella sativa seeds were found to possess good amount of phenols and flavonoids. The hydroxyl radical scavenging activity was observed to be 79.15 %±0.29 % at 120 μg/ml. The maximum cytotoxicity on psoriatic keratinocytes was found to be 71.50 %±0.74% at 250 μg/ml and half-maximal inhibitory concentration was calculated to be 31.8 μg/ml. Maximum cytotoxicity on A549 human lung cancer cell lines of 72.22 %±0.80 % was observed at 160 μg/ml and half-maximal inhibitory concentration was calculated to be 71.94 μg/ml. From these observations, it is evident that Nigella sativa seeds have excellent antioxidant, antipsoriatic and anticancer activities. This makes it a promising safe herbal based therapy in the treatment of psoriasis in comparison to commercially available drugs with adverse side effects.

Studies on Ethanolic Extract of Brown Seaweed Turbinaria ornata from Coastal Area of Tamil Nadu: In vitro Antioxidant and Anticancer Properties

Seaweeds are one of the most diverse bioreserves, including a wide range of bioactive compounds with various properties and functions. In present study, the antioxidant and anticancer activity of brown seaweed Turbinaria ornata was extracted using two different solvents like aqueous and ethanol. Higher concentrations of bioactive compounds were observed in ethanolic extract of T. ornata (EETO) in comparison to aqueous extract of T. ornata (AETO). The ethanolic extract showed potent antioxidant properties for DPPH and hydroxyl radical scavenging. The IC50 value of the ethanolic extract was found to be 48 and 50 μg/mL for DPPH and hydroxyl radical scavenging assay, respectively. Human breast adenocarcinoma (MCF-7) cells treated with different concentrations of the ethanolic extract showed a dose-dependent increase in cell inhibition. The LC50 value of the ethanolic extract was calculated to be 115.19 μg/mL and cell morphology was observed under an inverted phase-contrast microscope. As a result, based on the present findings, it is suggested that T. ornata extract might be a promising antioxidant and anticancer therapeutics.

Potential Hepatoprotective Effect of Cheatomorpha gracilis extract against High Fat Diet (HFD)-Induced Liver Damage, and its characterization by HPLC.

The current investigation was carried out to estimate the protective effect of aqueous extract of Cheatomorpha gracilis (AEC) against High fat Diet (HFD) induced liver damage in mice. The results of the in vitro study showed that AEC have higher antioxidant capacities in the DPPH and hydroxyl radical-scavenging assays. Indeed, many phenolic compounds (gallic acid, quercetin, naringenin, apigenin, kaempferol and rutin) were identified in the AEC. In the animal studies, during 6 weeks, HFD promoted oxidative stress with a rise level of malonaldehyde (MDA), protein carbonyls (PCOs) levels and a significant decrease of the antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase. Interestingly, the treatment with AEC (250 mg/kg body weight) significantly reduced the effects of HFD disorders on some plasmatic liver biomarkers (AST, ALT and ALP) in addition to, plasmatic proteins inflammatory biomarkers (α2 and β1 decreases / β2 and γ globulins increases). It can be suggest that supplementation of MECG displays high potential to quench free radicals and attenuates high fat diet promoted liver oxidative stress and related disturbances.

Protective Efficacy of Two Endemic Strobilanthes of Southern Western Ghats Kerala

Modern food habits in humans have increased the frequency of diseases especially colon cancer. The present findings suggest the potential efficacy of two endemic Strobilanthes species of Southern Western Ghats. The shoot extract of the plants showed high radical scavenging activity in hydroxyl scavenging assay at an half maximal inhibitory concentration of 375.24±2.03 and 375.24±2.03 μg/ml against gallic acid for Strobilanthes anamallaica and Strobilanthes virendrakumarana respectively. Their activity in the superoxidefree radical assay was moderate when compared with the standard. Among the two species, Strobilanthes virendrakumarana highly impacted colon cancer cells (DLD1) with an Lethal concentration 50 of 111.99±4.91 μg/ml. These concentrations do not affect the normal cell line L929 under consideration. Hence, the endemic plant of Southern-Western Ghats, viz., Strobilanthes virendrakumarana is a promising candidate against colon cancer cells.