Physicochemical, scavenging and anti-proliferative analyses of polysaccharides extracted from psyllium (Plantago ovata Forssk) husk and seeds

Polysaccharides extracted from seeds and husk of psyllium were characterized for different physicochemical characteristics, and bioactivities. Extracted polysaccharides are comprised of a-xylose, L-arabinose, a-glucose, D-galactose, and L-rhamnose. Crude husk-polysaccharide was crystalline, whereas rest was amorphous in nature. Husk-polysaccharide was structurally stable, and purified fractions were thermostable. Crude polysaccharides were irregular in shape with non-porous smooth-surface, however purified husk-polysaccharides showed some porosity, and fibrous nature. Husk-polysaccharide showed higher viscosity compared to seed polysaccharide, but viscosity decreased with the purification. Crude polysaccharides contained hydrogel-like behavior compared to corresponding purified fractions. The purified fractions of seed-polysaccharide showed the utmost antioxidant and scavenging activities with a half-maximal effective concentration of 347.40 1.79 and 362.72 2.75 lug, respectively. Crude seed-polysaccharide showed about 34% anti-proliferation on Huh-7, whereas its purified fractions showed 42% anti-proliferation on HeLa cell line. The study confirms that psyllium polysaccharides are potential natural antioxidant and anti-carcinogenic agent; however a detailed study is needed to explore psyllium for nutraceutical applications. (C) 2019 Elsevier B.V. All rights reserved.