Hypolipidemic and hypoglycemic effects of Centella asiatica (L.) extract in vitro and in vivo.

In vitro study revealed that pancreatic lipase inhibitory activity of C. asiatica extract was significantly higher than rutin but lower than orlistat, an anti-obesity drug. α-Amylase inhibitory activities of C. asiatica extract and rutin were significantly lower than acarbose, an anti-diabetic drug. Inhibition of α-glucosidase activity by C. asiatica extract, rutin, and acarbose was not different. The in vivo study substantiated the in vitro results. C. asiatica extract (1000 and 2000 mg/4 mL/kg), rutin (1000 mg/4 mL/kg), and orlistat (45 mg/4 mL/kg) significantly decreased plasma glucose, triglyceride and total cholesterol levels in lipid emulsion-induced hyperlipidemic rats at 3 h. However, plasma aspartate aminotransferase and alanine aminotransferase levels did not show significant change. The present work further supports that the C. asiatica extract and its bioactive rutin may help managing hypolipidemic and hypoglycemic effects.

Antioxidant and anti-lipid peroxidation activities of Tamarindus indica seed coat in human fibroblast cells.

Antioxidant activity and total phenolic content of tamarind seed coat extracts (TSCEs) were compared between the two extracts using boiling-water (TSCE-W) and 70% ethanol (TSCE-E) for extraction. TSCE-W, consisting of the highest phenolic content, possessed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and anti-lipid peroxidation activities much higher than TSCE-E and Trolox. Additionally, both TSCEs also exhibited superoxide anion and hydrogen peroxide scavenging activities higher than Trolox and BHA. Anti-lipid peroxidation and cytotoxicity of TSCE-W were also studied in human foreskin fibroblast CCD-1064Sk cells. Cytotoxic effect was not observed when exposed to TSCE-W up to 1 mg/mL for 12-48 h. However, TSCE-W significantly attenuated lipid peroxidation in H2O2-damaged cells. HPLC analysis showed the presence of (+)-catechin, (-)-epicatechin, and procyanidin B2 in TSCE-W, which could be responsible for antioxidant and anti-lipid peroxidation activities. The results suggest that an inexpensive and simple boiling-water extraction of TSCE-W may provide a valuable natural antioxidant source having anti-lipid peroxidation for health food additives, nutraceuticals as well as cosmeceuticals.