Centella asiatica (L.) Urb. EXTRACTS: EFFECT OF EXTRACTION CONDITIONS ON BIOACTIVITY AND PHYTOCHEMICAL COMPOSITION

Abstract

This study aimed to preliminarily analyze the phytochemical composition and evaluate factors affecting the bioactivity of Centella asiatica (L.) Urb. extracts. C. asiatica sample was collected in a local garden in Tien Giang province under traditional local cultivation conditions; the VietGAP C. asiatica sample was also collected for comparison. The results showed a strong effect of solvents on the phytochemical content and bioactivity of the C. asiatica extract when using the ultrasonic-assisted extraction technique. The ethanol/water (3:2 v/v) solvent provided the highest antioxidant extract, while the ethanol solvent supported the extraction of antibacterial compounds. The appropriate conditions for antioxidant activity-guided extraction were determined including ethanol/water (3:2 v/v) solvent, extraction time of 45 min, and temperature of 40 oC. Under these conditions, the total saponin content, total phenolic content, and total flavonoid content of the extract were 24.15 ± 0.04 mg oleanolic/g, 22.17 ± 0.63 mg GAE/g, and 21.25 ± 0.46 mg RE/g, respectively. The C. asiatica sample under VietGAP had a higher amount of total saponins than the C. asiatica sample collected in the local garden, while the latter contained higher amounts of phenolics and flavonoids.