Phytochemical screening, in vitro and in vivo antioxidant activities of Aqueous extract of Anacardium occidentale Linn. and its effects on Endogenous Antioxidant Enzymes in Hypercholesterolemic induced rabbits.

Oxidative stress has been shown to play important role in the development of various diseases. In this study, researchers investigated the existence of phytochemical constituents of Anacardium occidentale Linn. (AO) leaf and evaluate its in vitro and in vivo antioxidant activities in aqueous extract form. Phytochemical screening of AO was performed according to the standard method while in vitro antioxidant activities were performed via DDPH free radical scavenging and Ferric reducing antioxidant power assay. In vivo antioxidant activities were evaluated in hypercholesterolemic induced adult male New Zealand white rabbits. Phenolic, flavonoids, steroids and triterpenes were found in the leaf of AO. The freeze dried aqueous extract showed no significant different compared to BHT in in vitro antioxidant analysis when assessed using the FRAP assay. Supplementation of aqueous extract of AO (100, 200 mg/kg/day) to the hypercholesterolemic induced rabbits caused a significant decreased (p<0.05) of malondialdehyde and significant increased (p<0.05) of superoxide dismutase and catalase levels at the end of the study period compared to the groups received high cholesterol diet alone. Aqueous extract of AO possess the ability to act as an antioxidant in vitro and in vivo and also was able to increase the level of superoxide dismutase and catalase in experimental hypercholesterolemia. The presence of flavonoids in the extract could be attributed to the antioxidative effect of the plant

Antioxidant properties of aqueous and methanol extract from Tinospora crispa and its ability to Attenuate Hydrogen Peroxide-induced stress injury in human umbilical Vein Endothelial cells.

The aimed of this study was to investigate the antioxidant properties of T. crispa as well as its ability to attenuate the release of oxidant markers in induced oxidation in Human Umbilical Vein Cells (HUVECs). In vitro studies of antioxidant properties of T. crispa showed the DPPH scavenging activity of T. crispa Aqueous (TCAE) and Methanol Extract (TCME) were 82±1.78 and 73±1.01%, respectively. FRAP value of TCAE and TCME were 1.04±0.27 and 1.64±0.06 mmol L-1, respectively. Total Flavonoids Content (TFC) of TCAE and TCME were 205.58±3.5 and 223±10.49 mg QE g-1 sample, respectively while Total Phenolics Content (TPC) of TCAE and TCME were 32.58±0.68 and 41.64±0.97 mg GAE mg-1 sample, respectively. The antioxidant enzymes activities (CAT, SOD and GPx) in HUVECs treated with T. crispa extracts to counter the oxidative effect by hydrogen peroxide (H2O2) and lipid peroxidation activity by Malondialdehyde (MDA) were also measured. The result showed TCAE and TCME at a concentration ranges from 100-600 μg mL-1 significantly increased (p<0.05, 0.01) the level of CAT, SOD and GPx. Results of MDA assay showed significant reduction (p<0.05, 0.01) of MDA level in HUVECs treated with TCAE and TCME. Taken together, the findings suggest that T. crispa extracts can effectively protect HUVECs against oxidative stress by H2O2 which might be of importance in the treatment of cardiovascular diseases