Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology

BACKGROUND: Momordica charantia Linn. (Cucurbitaceae) fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. OBJECTIVE: The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. MATERIALS AND METHODS: Response surface methodology (RSM) was used for the optimization of ultrasound-assisted extraction (UAE) conditions. RSM was based on a three-level, three-variable Box-Behnken design (BBD), and the studied variables included solid to solvent ratio, extraction temperature, and extraction time. RESULTS: The optimal conditions predicted by the BBD were: UAE with methanol: Water (80:20, v/v) at 46°C for 120 min with solid to solvent ratio of 1:26 w/v, under which the yield of charantin was 3.18 mg/g. Confirmation trials under slightly adjusted conditions yielded 3.12 ± 0.14 mg/g of charantin on dry weight basis of fruits. The result of UAE was also compared with Soxhlet extraction method and UAE was found 2.74-fold more efficient than the Soxhlet extraction for extracting charantin. CONCLUSIONS: A facile UAE protocol for a high extraction yield of charantin was developed and validated.