title: Ultrasonic effects on the degradation kinetics, preliminary characterization and antioxidant activities of polysaccharides from Phellinus linteus mycelia.
abstract: In this study, a high-molecular-weight polysaccharide PL-N isolated from the alkaline extract of Phellinus linteus mycelia was degraded by ultrasound. Results showed that ultrasound treatment at different ultrasonic intensities decreased the intrinsic viscosity and molecular weight of PL-N, as well as narrowed the molecular weight distribution. A larger reduction in intrinsic viscosity and molecular weight was caused by a higher ultrasonic intensity. The degradation kinetics model was fitted to (1/Mt-1/M0)=k·t, and the reaction rate constant (k) increased with increasing ultrasonic intensity. Ultrasound degradation did not change the primary structure of PL-N, and scanning electron microscopy analysis indicated that the morphology of the original PL-N was different from that of degraded PL-N fractions. Antioxidant activity assays in vitro indicated that the degraded PL-N fraction with low molecular weight had stronger hydroxyl radical scavenging capacity and higher TEAC and FRAP values.
authors.affiliation: School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China; Physical Processing of Agricultural Products Key Lab of Jiangsu Province, Zhenjiang 212013, Jiangsu, China. Electronic address: jkyan_27@163.com.
authors.forename: Jing-Kun
authors.initials: JK
authors.lastname: Yan
authors.affiliation: School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Yao-Yao
authors.initials: YY
authors.lastname: Wang
authors.affiliation: School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China; Physical Processing of Agricultural Products Key Lab of Jiangsu Province, Zhenjiang 212013, Jiangsu, China.
authors.forename: Hai-Le
authors.initials: HL
authors.lastname: Ma
authors.affiliation: School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China; Physical Processing of Agricultural Products Key Lab of Jiangsu Province, Zhenjiang 212013, Jiangsu, China.
authors.forename: Zhen-Bin
authors.initials: ZB
authors.lastname: Wang
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D001487:Basidiomycota / Q000737:chemistry*; D007700:Kinetics; D008970:Molecular Weight; D025282:Mycelium / Q000737:chemistry*; D058105:Polymerization; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000069453:Ultrasonic Waves; D014783:Viscosity
chemical_list: D000975:Antioxidants; D011134:Polysaccharides
keywords: Antioxidant activity; Degradation kinetics; Phellinus linteus; Polysaccharide; Preliminary characterization; Ultrasonic treatment