title: Optimal production of 4-deoxy-L-erythro-5-hexoseulose uronic acid from alginate for brown macro algae saccharification by combining endo- and exo-type alginate lyases.
abstract: Algae are considered as third-generation biomass, and alginate is the main component of brown macroalgae. Alginate can be enzymatically depolymerized by alginate lyases into uronate monomers, such as mannuronic acid and guluronic acid, which are further nonenzymatically converted to 4-deoxy-L-erythro-5-hexoseulose uronic acid (DEH). We have optimized an enzymatic saccharification process using two recombinant alginate lyases, endo-type Alg7D and exo-type Alg17C, for the efficient production of DEH from alginate. When comparing the sequential and simultaneous additions of Alg7D and Alg17C, it was found that the final yield of DEH was significantly higher when the enzymes were added sequentially. The progress of saccharification reactions and production of DEH were verified by thin layer chromatography and gas chromatography-mass spectrometry, respectively. Our results showed that the two recombinant enzymes could be exploited for the efficient production of DEH that is the key substrate for producing biofuels from brown macro algal biomass.
authors.affiliation: Department of Biotechnology, Korea University Graduate School, Seoul, 136-713, Republic of Korea.
authors.forename: Da Mao
authors.initials: DM
authors.lastname: Wang
authors.forename: Hee Taek
authors.initials: HT
authors.lastname: Kim
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Yun
authors.forename: Do Hyoung
authors.initials: DH
authors.lastname: Kim
authors.forename: Yong-Cheol
authors.initials: YC
authors.lastname: Park
authors.forename: Hee Chul
authors.initials: HC
authors.lastname: Woo
authors.forename: Kyoung Heon
authors.initials: KH
authors.lastname: Kim
mesh_terms: D000464:Alginates / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D003837:Deoxy Sugars / Q000096:biosynthesis*; D008401:Gas Chromatography-Mass Spectrometry; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D009844:Oligosaccharides / Q000096:biosynthesis*; D000459:Phaeophyceae / Q000378:metabolism*; D011133:Polysaccharide-Lyases / Q000378:metabolism*; D014574:Uronic Acids / Q000378:metabolism*
chemical_list: D000464:Alginates; D003837:Deoxy Sugars; D006603:Hexuronic Acids; D009844:Oligosaccharides; D014574:Uronic Acids; D020723:Glucuronic Acid; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase