Effect of ultrasound on extraction of polysaccharides from green pea pod

Polysaccharides are biomacromolecules which have an important role in the human diet to scavenge free radicals preventing oxidative damages. In this study, the effects of ultrasonic power (50- 100- 150- 200 W) and duty cycle (50- 100%) at frequency of 24 KHz on extraction yield of polysaccharides from green pea pod as a by-product of food processing premises were studied. Polysaccharide extraction was performed at extraction temperature of 60°C, extraction time of 50 min and water to raw material ratio of 30:1 mL:g. The maximum extraction yield (7.14±0.01%) was obtained with ultrasonic power of 150 W and duty cycle of 100%. This finding indicated that ultrasound treatment in comparison with traditional methods can enhance the extraction yield. The green pea pod polysaccharides have been analyzed in order to identify a variety of chemical properties. FT-IR spectrum demonstrated obvious characteristic peaks of polysaccharides. Antioxidant activity of green pea pod polysaccharides was determined by DPPH, RP and FRAP assays. Finally, polysaccharides extracted from green pea pod as a as a natural and low cost source for extraction of value added products can be used as a novel and natural antioxidant agent for functional food production.