title: Chemical structure and antioxidant activity of the biomacromolecules from paddlefish cartilage.
abstract: To evaluate the effect of extraction methods on chemical structure and association with antioxidant activity of the extracts from paddlefish cartilage, the three extracts (EXT-A, EXT-B and EXT-C) were obtained from the cartilage by signal alkali extraction, microwave-assisted alkali extraction, and microwave-assisted alkali extraction followed by Sevag's deproteinization, respectively. Chemical structures of the polymer were investigated by GPC (Gel Permeation Chromatography), FT-IR, GC and amino acid analysis. The results indicated that both EXT-A and EXT-B consisted of polysaccharide and protein, but the protein content of EXT-B (87.9%) was significantly higher than EXT-A (22.3%). Meanwhile EXT-C was polysaccharide composed of glucose, galactose, D-glucuronic acid and xylose. EXT-B extracted by microwave-assisted alkali method, containing dominant protein and rich in tyrosine, glycine and glutamic acid, exhibited obviously higher antioxidant activity than those of the extracts by other methods. The results indicated that microwave-assisted alkali extraction was favorable for protein dissolving out of cartilage, and protein content and composition of the extracts play important roles in antioxidant activity.
authors.affiliation: College of Food Sciences and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Liangzi
authors.initials: L
authors.lastname: Zhang
authors.forename: Siming
authors.initials: S
authors.lastname: Zhao
authors.forename: Shanbai
authors.initials: S
authors.lastname: Xiong
authors.forename: Qilin
authors.initials: Q
authors.lastname: Huang
authors.forename: Shuo
authors.initials: S
authors.lastname: Shen
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology*; D002356:Cartilage / Q000737:chemistry*; D002839:Chromans / Q000378:metabolism; D002849:Chromatography, Gas; D002850:Chromatography, Gel; D045424:Complex Mixtures; D005399:Fishes / Q000378:metabolism*; D036681:Fluorescence Recovery After Photobleaching; D046911:Macromolecular Substances / Q000737:chemistry* / Q000494:pharmacology*; D009005:Monosaccharides / Q000032:analysis; D012015:Reference Standards; D013055:Spectrophotometry, Infrared
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D002839:Chromans; D045424:Complex Mixtures; D046911:Macromolecular Substances; D009005:Monosaccharides; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid