Effects of extraction conditions on total saponin and total polyphenol contents in extracts from hydroponically grown Centella asiatica (L.) Urb. tubers

This study determines suitable extraction conditions, including the material-to-solvent ratio, temperature, and extraction time, for obtaining bioactive compound-rich extracts from hydroponically grown Centella asiatica (L.) Urb. tubers. Total saponin and total polyphenol contents were used as the main evaluation criteria. The optimal conditions were a material-to-solvent ratio of 1:20 (g/mL), an extraction temperature of 70°C, and an extraction time of 60 minutes. Under these conditions, total saponin content reached 6.48 ± 0.03%, while total polyphenol content reached 24.41 ± 0.77 mg GAE/mL of extract. The findings provide a basis for developing an efficient extraction process and enhancing the utilization value of hydroponically grown C. asiatica tubers for potential applications in functional foods and herbal medicinal products.