title: Amylolytic hydrolysis of native starch granules affected by granule surface area.
abstract: Initial stage of hydrolysis of native starch granules with various amylolytic enzymes, alpha-amylase from Bacillus subtilis, glucoamylase I (GA-I) and II (GA-II) from Aspergillus niger, and beta-amylase from sweet potato showed that the reaction was apparently affected by a specific surface area of the starch granules. The ratios of the reciprocal of initial velocity of each amylolytic hydrolysis for native potato and maize starch to that for rice with the amylolytic enzymes were nearly equivalent to the ratio of surface area per mass of the 2 starch granules to that of rice, that is, 6.94 and 2.25, respectively. Thus, the reciprocal of initial velocity of each enzymatic hydrolysis as expressed in a Lineweaver-Burk plot was a linear function of the reciprocal of surface area for each starch granule. As a result, it is concluded that amylolytic hydrolysis of native starch granules is governed by the specific surface area, not by the mass concentration, of each granule.
authors.affiliation: School of Food and Life Science, Inje University, Gimhae, Gyeongnam 621-749, Republic of Korea. jckim@inje.ac.kr
authors.forename: J C
authors.initials: JC
authors.lastname: Kim
authors.forename: B W
authors.initials: BW
authors.lastname: Kong
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.forename: S H
authors.initials: SH
authors.lastname: Lee
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology; D001412:Bacillus subtilis / Q000201:enzymology; D001426:Bacterial Proteins / Q000378:metabolism; D027742:Dioscorea / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism; D005656:Fungal Proteins / Q000302:isolation & purification / Q000378:metabolism; D005087:Glucan 1,4-alpha-Glucosidase / Q000302:isolation & purification / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D012275:Oryza / Q000378:metabolism; D011198:Solanum tuberosum / Q000378:metabolism; D013213:Starch / Q000737:chemistry* / Q000378:metabolism*; D013499:Surface Properties; D003313:Zea mays / Q000378:metabolism; D000516:alpha-Amylases / Q000378:metabolism; D001614:beta-Amylase / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D005656:Fungal Proteins; D013213:Starch; D000516:alpha-Amylases; D001614:beta-Amylase; D005087:Glucan 1,4-alpha-Glucosidase