title: Microwave-assisted extraction of jujube polysaccharide: Optimization, purification and functional characterization.
abstract: The operational parameters involved in microwave-assisted extraction (MAE) of jujube polysaccharide including microwave power, water to raw material ratio and extraction temperature and time were optimized by RSM. MAE at 400W, 75°C, 60 min, using 30 g water/g powdered jujube was the best condition for maximum yield (9.02%) of polysaccharide. Two novel water-soluble polysaccharides (JCP-1 and JCP-2) with average molecular weights of 9.1×10(4)-1.5×10(5)Da in term of the symmetrical narrow peaks were identified using the analytical purification procedures. The JCP-1 and JCP-2 mainly composed of glucose, arabinose, galactose and rhamnose in molar ratios of 1.4:2.1:4.2:0.9 and 1.2:1.8:4.1:1.1, respectively. The use of 1.5% JCP-1 led to a high emulsifying stability (95.5%) in a model oil-in-water type emulsion with a reduced surface tension (44.1 mN/m) and droplet size (1.32 μm), and an increased apparent viscosity (0.13 Pas) during 21-day cold storage. The antioxidant activities were increased in dose-dependent manners (25-200 μg/mL).
authors.affiliation: Health Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Hosein
authors.initials: H
authors.lastname: Rostami
authors.affiliation: Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran 14778-93855, Iran. Electronic address: smt.gharibzahedi@gmail.com.
authors.forename: Seyed Mohammad Taghi
authors.initials: SM
authors.lastname: Gharibzahedi
mesh_terms: D005591:Chemical Fractionation; D045703:Emulsifying Agents / Q000737:chemistry* / Q000302:isolation & purification; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification; D006361:Heating / Q000379:methods; D008872:Microwaves; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D013500:Surface Tension; D014783:Viscosity; D031957:Ziziphus / Q000737:chemistry*
chemical_list: D045703:Emulsifying Agents; D016166:Free Radical Scavengers; D011134:Polysaccharides
keywords: Antiradical activity; Average molecular weight; Emulsifying activity; Extraction optimization; Surface activity; Zizyphus jujuba mucilage