title: Enzymatic desulfation of the red seaweeds agar by Marinomonas arylsulfatase.
abstract: Agar and sulfated galactans were isolated from the red seaweeds Gracilariopsis lemaneiformis and Gelidium amansii. A previously purified arylsulfatase from Marinomonas sp. FW-1 was used to remove sulfate groups in agar and sulfated galactans. After enzymatic desulfation, the sulfate content decreased to about 0.16% and gel strength increased about two folds. Moreover, there was no difference between the DNA electrophoresis spectrum on the gel of the arylsulfatase-treated agar and that of the commercial agarose. In order to reveal the desulfation ratio and site, chemical and structural identification of sulfated galactan were carried out. G. amansii sulfated galactan with 7.4% sulfated content was composed of galactose and 3,6-anhydro-l-galactose. Meanwhile, G. lemaneiformis sulfated galactan with 8.5% sulfated content was composed of galactose, 3,6-anhydro-l-galactose, 2-O-methyl-3,6-anhydro-l-galactose and xylose. Data from13C NMR, FT-IR, GC-MS provided evidence of sulfate groups at C-4 and C-6 of d-galactose and C-6 of l-galactose both in GRAP and GEAP. Data from GC-MS revealed that desulfation was carried out by the arylsulfatase at the sulfate bonds at C-4 and C-6 of d-galactose and C-6 of l-galactose, with a desulfation ratio of 83.4% and 86.0% against GEAP and GRAP, respectively.
authors: College of Food Science and Engineering, Ocean University of China, No. 5 Yushan Road, Qingdao, 266003, China.
authors: Xueyan
authors: X
authors: Wang
authors: Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
authors: Delin
authors: D
authors: Duan
authors: College of Food Science and Engineering, Ocean University of China, No. 5 Yushan Road, Qingdao, 266003, China. Electronic address: xiaotingfu@ouc.edu.cn/.
authors: Xiaoting
authors: X
authors: Fu
mesh_terms: D000362:Agar / Q000737:chemistry* / Q000378:metabolism; D001192:Arylsulfatases / Q000378:metabolism*; D005690:Galactose / Q000737:chemistry; D044724:Gracilaria / Q000737:chemistry*; D053544:Marinomonas / Q000201:enzymology*; D008745:Methylation
chemical_list: D000362:Agar; D001192:Arylsulfatases; D005690:Galactose
keywords: Arylsulfatase agarose desulfation sulfated galactan spectroscopy