Process Optimization of the Extraction of Moringa oleifera Seed Polyphenols by Ultrasound-Assisted Cellulase and Its in Vitro Activity

In this study, the effects of cellulase addition, ethanol volume fraction, cellulase digestion time and ultrasound time on the extraction rate of Moringa oleifera seeds polyphenols were investigated. At the same time, the extraction process of Moringa oleifera seeds polyphenols by ultrasound-assisted cellulase method was optimized using response surface methodology. In addition, the in vitro antioxidant and hypoglycemic and hypolipidemic activities of Moringa oleifera seeds polyphenols were also investigated. The results showed that the optimal process for the extraction of Moringa oleifera seed polyphenols by ultrasound-assisted cellulase was 0.30% enzyme addition, 53.00% volume fraction of ethanol, 31.00 min enzymatic digestion time, and 31.00 min ultrasound time. Under this process condition, the amount of Moringa oleifera seed polyphenols extracted obtained was 6.90 mg/g, which was not significantly different from the predicted value. In addition, the study found that Moringa oleifera seed polyphenols had good antioxidant activity, and its IC50 for scavenging ABTS radicals and DPPH radicals were 0.76 and 0.61 mg/mL, respectively. Meanwhile, Moringa oleifera seed polyphenols had some pancreatic lipase and α-amylase inhibitory activities, and theirs IC50 for pancreatic lipase and α-amylase inhibition rate were 1.35 and 6.55 mg/mL, respectively. This study provides a theoretical basis for the extraction and application of Moringa oleifera seed polyphenols.