Ultrasound- and enzyme-assisted extraction of <i>Moringa oleifera</i> polysaccharides: bioactivity evaluation

Polysaccharides from Moringa oleifera (PMS) leaves were extracted using neutrase (PMS-N) or savinase (PMS-S) enzymes combined with ultrasonic (US) treatment, and their biological activities were investigated. Both US time (10 min) and enzyme type positively influenced PMS yield, regardless of the enzyme used. Among the detected neutral sugars, xylose was the major monosaccharide in US-pretreated PMS, reaching 72% and 69% in PMS-S-US-10 and PMS-N-US-10, respectively. In addition, US-pretreated PMS exhibited the highest antioxidant capacities and significantly prolonged blood clotting period and reduced fibrinogen levels, accomplishing 0.7 g/L and 1.5 g/L, by the addition of PMS-S-US-10 and PMS-N-US-10, respectively. Antiproliferative assays revealed dose-dependent inhibition effect of PMS against two types of cancer cells, where PMS-S-US-10 displayed the highest inhibitory rates, reaching 96% and 99% (at 200 µg/mL) against K562 and Caco-2 cells, respectively.