Total phenolic content, Free radical scavenging and Antimicrobial activities of Passiflora subpeltata seeds.

The study aimed to investigate the antioxidant and antimicrobial activities of seeds from Passiflora subpeltata. The powdered seed material was subjected to successive solvent extraction in a soxhlet extractor. The antioxidant activities were analyzed the methods of DPPH•, ABTS•+, superoxide radical scavenging and metal chelating activity. The antimicrobial activities of seeds were performed by disc diffusion method. The acetone extract of P. subpeltata seed recorded highest total phenolic (340.70 mg GAE / g extract) and tannin (214.30 mg GAE / g extract) contents and possessed high antioxidant activity. The IC50 value of DPPH was (26.37 μg/mL) and the scavenging activity of superoxide radical was (75.18%). P. subpeltata seeds also demonstrated an effective antibacterial property against seven pathogens and antifungal property against two pathogens tested. Therefore, the results suggest that the seeds of P. subpeltata have promising therapeutic value for natural antioxidant and antimicrobial properties.

Free radical scavenging property and antiproliferative activity of Rhodiola imbricata Edgew extracts in HT-29 human colon cancer cells

OBJECTIVE@#To investigate the in vitro antioxidant and antiproliferative activity of rhizome extracts of Rhodiola imbricata (R. imbricata) in HT-29 human colon cancer cell line.@*METHODS@#The successively extracted rhizome of R. imbricata using various solvents was analyzed for their total phenolics, tannins and flavonoid contents. In vitro antioxidant activity was evaluated by employing different assays, including DPPH, ABTS radical scavenging assays, FRAP, phosphomolybdenum reduction assay, superoxide anion, hydroxyl radical scavenging activities and metal chelating ability.@*RESULTS@#Acetone and methanol extracts recorded higher phenolic content and showed comparable antioxidant activity with standard reference. Additionally, they also inhibited the proliferation of HT-29 cells upon treatment at higher concentration (200 μg/mL) (acetone and methanol, 84% and 84%, respectively). On examination acetone extract exhibited antiproliferative activity in a concentration dependent manner whereas, methanol extract showed both dose dependent and time dependent inhibitory activity.@*CONCLUSIONS@#The results obtained justify the traditional usage of R. imbricata from their promising antioxidant activity.

Antidiabetic activity of aqueous root extract of Merremia tridentata (L.) Hall. f. in streptozotocin-induced-diabetic rats

OBJECTIVE@#To investigate the antidiabetic effect of aqueous extract of Merremia tridentata (M. tridentata) root (MTRAE) in normal, glucose-loaded hyperglycemic and streptozotocin (STZ)-induced diabetic rats.@*METHODS@#Oral administration of MTRAE at the doses of 50, 100 and 150 mg/kg was studied in normal, glucose-loaded and STZ-diabetic rats. The three doses caused significant reduction in blood glucose levels in all the models.@*RESULTS@#The effect was more pronounced in 100 and 150 mg/kg than 50 mg/kg. MTRAE also showed significant increase in serum insulin, body weight and glycogen content in liver and skeletal muscle of STZ-induced diabetic rats while there was significant reduction in the levels of serum triglyceride and total cholesterol. MTRAE also showed significant antilipidperoxidative effect in the pancreas of STZ-induced diabetic rats. The antidiabetic effect of M. tridentata was compared with glibenclamide, a well known hypoglycemic drug.@*CONCLUSIONS@#The results indicate that aqueous extract of M. tridentata root possesses significant antidiabetic activity.