A systematic review and meta-analysis extraction techniques to reach the optimum asiaticoside content from the edible plant of Centella asiatica

• Methanol solvent was suitable to extract asiaticoside by using maceration method. • Ethanol solvent was appropriate for almost all solid-liquid extractions. • Ethanol-aqueous solution (50–80%) increases the asiaticoside extraction efficiency. • Extracting at the boiling point of the solvent increases the asiaticoside content. • Microwave-assisted extraction is the most potential method to extract asiaticoside. Asiaticoside is a promising compound of Centella asiatica . This review aims to investigate the effect of solid-liquid extraction techniques on asiaticoside yield. This research followed PRISMA guidelines. Of 361 studies identified, thirteen met inclusion criteria, and three were analyzed by meta-analysis. Qualitative findings showed that green extractions of ultrasound-assisted (UAE) and microwave-assisted (MAE) were more efficient than conventional extractions of maceration and heat-assisted (HAE). Solvent studies exhibited specific optimum solvents for each method, such as methanol for maceration and ethanol for HAE, UAE, and MAE. Meta-analysis generated findings that ethanol was more efficient than water for maceration (Zscore of 31.34) and HAE (Zscore of 27.32). HAE significantly increased the asiaticoside yield ( Z score of 17.89). There was no significant difference between UAE and MAE ( P -value of 0.37). In conclusion, the optimum asiaticoside extraction is afforded by using ethanol at elevated temperatures. Moreover, MAE is a potential method requiring less extraction time.