Chemical Constituents, in Vitro Antioxidant Activity, Oral Acute Toxicity and Ld50 Determination of Moringa Oleifera Leaves

Objective: The present study focuses on the synthesis of silver and zinc oxide (ZnO) nanoparticles from marine yeasts, isolated from the sediments of the Bay of Bengal, Bakkhali coast, West Bengal, and India. Methods:The marine sediment samples were diluted through serial diution and cultured onto yeast malt agar medium by the spread plate method. The selected yeast isolates were screened for the biosynthesis of silver and ZnO nanoparticles. Characterization of both the nanoparticles was done by applying ultraviolet (UV)-visible spectroscopy, atomic force microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy.Results: A total of five marine yeasts isolates were able to synthesize silver and ZnO nanoparticles as evidence of the color change. Optical density was measured in UV-spectrometer at different time interval for the conformation of production of nanoparticles. The size of silver nanoparticle was 31.78 nm and ZnO nanoparticle was 86.27 nm. The synthesized nanoparticles are then used for antioxidant assays. Conclusions:We are concluding that marine yeast isolates SAG1 and SAG2 both are potential marine yeast isolates which can synthesize both the silver and ZnO nanoparticles. They also showed good antioxidant activity.

Section: Discussionmentioning

confidence: 53%

Section: Uv-spectrometer Analysis Of Silver and Zno Nanoparticlesmentioning

confidence: 95%

Green Synthesis and Characterization of Marine Yeast-Mediated Silver and Zinc Oxide Nanoparticles and Assessment of Their Antioxidant Activity

Aswathy

Gabylis

et al. 2017

“…Antioxidant activity [25] of the extracts was performed using method 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging [26,27]. 1 ml of 0.1 mM solution of DPPH in methanol was added to 3 ml of the solution of all the extracts in ethanol at different concentrations (5,20,40,60,80, and 100 µg/ml).…”

Section: Antioxidant Assaymentioning

confidence: 99%

“…As the leaves of the plant possess antimicrobial potency, the stem bark was screened for antimicrobial activity [25,28]. Four microbes, i.e., Gram-positive bacteria such as Staphylococcus aureus and Bacillus subtilis while Gram-negative Escherichia coli and Klebsiella pneumoniae were used.…”

Section: Antimicrobial Activitymentioning

confidence: 99%

A STUDY ON PHYTOCHEMICAL SCREENING, ANTIOXIDANT, ANTIMICROBIAL AND Α-Αmylase INHIBITORY ACTIVITIES OF CRUDE EXTRACTS OF THE STEM BARK OF PISONIA GRANDIS, R.BR

Mohan

Ramasamy

Vemuri

et al. 2017

Objective: The aim of the present study is to determine the phytochemical screening, antioxidant activity and α-amylase inhibitory activity of the crude hexane, ethyl acetate and ethanolic stem bark extract of Pisonia grandis. Methods:The evaluation of antioxidant and antimicrobial activity, total phenolic, and flavonoid content were assessed using 2,2-diphenyl-1-picrylhydrazyl, Folin-Ciocalteu's reagent, and aluminum chloride assay, respectively. The antidiabetic activity was assessed for porcine pancreatic α-amylase for the stem bark of P. grandis.Results: Phytochemical screening confirmed the presence of phenolic, flavonoids, tannins, saponins, terpenoids, and steroids in all the three extracts. The antioxidant activity showed 148.2 µg/ml, total phenolic content (gallic acid equivalent), 0.0665±0.0002 mg/g, flavonoid content (quercetin equivalent), 0.6061±0.1817 mg/g, and inhibitory concentration 50% values were found to be 40.42 µg/ml and showed better in ethyl acetate extract. The antidiabetic activity exhibited mimic action with insulin due to the presence of pinnatol in the stem bark and leaves of P. grandis. Conclusion:P. grandis stem bark crude ethyl acetate extract showed strong antioxidant activity, high phenolic, and flavonoid content. The antimicrobial activity was studied in both Gram-positive and Gram-negative strains against ampicillin and rifampicin as reference drugs. Antidiabetic activity shows effective result by α-amylase inhibitory activity.

“…The AO potential and antiradical unit (AU) activity of EGB761 and GBME were estimated by both ABTS and DPPH assays [22].…”

Section: Radical Scavenging Assays (22'-azino-bis(3-ethylbenzothiazomentioning

confidence: 99%

Antioxidant, Cytotoxicity, and Stability Evaluation of Ginkgo Biloba Extract-Based Microemulsions for Enhanced Therapeutic Activity

Singh

Rachana

2017

Objective: This study is aimed to evaluate the antioxidant (AO) potential, cytotoxicity, and stability of preformulated Ginkgo biloba standard extract microemulsion (GBME), to investigate if, it retains the therapeutic potential of EGB761 and remains safe and stable for a longer period. Method and Results: GBME has shown enhanced AO (85.2±0.78%, IC 50 =31.3±0.45 µg/ml) in comparison to EGB761 (74.1±0.51%, IC 50 =49.4±0.05 µg/ml) using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay. Similarly, 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay has also shown that AO for GBME (94.6±0.04%, IC 50 =11.4±1.03 µg/ml) was higher than EGB761 (78.6±1.20%, IC 50 =34.6±0.81 µg/ml). Further, IC 50 value of antiradical unit of GBME was much lesser (ABTS=14.3±1.05 µg/ml and DPPH=17.03±1.8 µg/ml) in comparison to EGB761 (ABTS=34.1±1.62 µg/ml and DPPH=37.5±0.08 µg/ml). Equivalently, both, hydrogen peroxide scavenging activity, and nitric oxide activity were appreciably higher for GBME than the pure extract. The in vitro cytotoxicity assessment showed that GBME is quite safe (98.68±0.76% cell viability) in comparison to EGB761 (83.29±1.02%). Thereafter, these samples were tested for stability by evaluating their AO activity along with high-performance liquid chromatography analysis, for the major phytocompounds, after 1 year, and results suggested that AO of GBME remained stable while comparing with the freshly prepared GBME, whereas AO of EGB761 reduced significantly as compared to freshly taken EGB761 extract implying the degradation of phytocompounds supporting decrease in AO activity.Conclusion: Therefore, the observed results suggest that GBME maintained AO and scavenging activity along with enhanced shelf life with no observed toxicity, which can be explored further for its potential therapeutic implications in various oxidative stress-induced central nervous system disorders.