Experimental design of hydrotropic extraction for recovery of bioactive limonin from lemon (Citrus limon L.) seeds

A potential bioactive compound limonin is found in citrus fruits, especially tremendous extent in seeds. In this study, an attempt has been made to develop a novel and proficient extraction method by using the hydrotrope solution to recover limonin from lemon (Citrus limon L.) seeds. Initially, the extraction time (4 h) was screened by varying the time from 3 to 6 h by fixing the concentration of hydrotrope (sodium salicylate), raw material loading and temperature of the extraction. To enhance the yield of hydrotrope extraction, Box-Behnken experimental design (BBD) was proposed. The maximum yield of limonin recovered was 6.41 mg g(-1) at optimized process conditions such as the hydrotrope concentration of 1.65 M, raw material loading of 8.08%, and temperature of 44 degrees C. The obtained limonin yield in this study was higher compared to the other studies using different citrus seeds. The recovered limonin was identified by using Fourier Transform-Infrared Spectroscopy (FTIR) and high-performance liquid chromatography (HPLC). Furthermore, the scavenging ability was evaluated for the extracted limonin, and it is proved to be a potent antioxidant. Therefore, the results revealed that the extraction of bioactive compounds using hydrotrope is efficient, eco-friendly and can also lower the usage of organic chemicals.