Extraction, enrichment flavonoid, and evaluation of antioxidant activity of Passiflora foetida extract

Abstract

Passiflora foetida L., commonly known as "Lạc tiên" in Vietnam, is a widely used medicinal plant in Vietnamese traditional medicine to treat diseases such as sedation, fever reduction, liver cooling, nervous breakdown, heart palpitations, and insomnia. In the study, the appropriate conditions for the extraction of P. foetida extract were determined, including using 80% ethanol as the solvent, a solvent-to-material ratio of 10:1, an extraction temperature of 80°C, an extraction time of 120 minutes, and number of extractions 3 times. Activated charcoal was employed to remove chlorophyll before enriching flavonoids in the extract using Diaion HP20 resin. The enrichment process utilized 10% ethanol as the loading solvent, with an extract-to-resin ratio of 16:30 (w/w). Elution with 70% ethanol increased the flavonoid content in the extract to 13.89%. Furthermore, the enriched extract exhibited strong antioxidant activity, with an IC₅₀ value of 34.25 µg/mL.