title: Hydrolysis of D-galactosides in an open tubular lactase reactor.
abstract: Lactase (beta-galactosidase) was attached to the inner surface of nylon tubing. Tubes of various lengths were used to bring about the hydrolysis of o-nitrophenyl-beta-D-galactoside and of lactose in skim milk. The results with the former substrate were analyzed in the light of a theoretical treatment of Kobayashi and Laidler (Biotechnol. Bioeng., 16, 99, 1974), with the conclusion that the reaction is intermediate between diffusion-free and completely diffusion-controlled behavior. The results with skim milk show that with a single 46 m tube and continuous circulation, 90% of the lactose is removed within 20 hr. A battery of ten such tubes, with single passage, at a flow rate of 2 cm/sec, would remove more than 99% of the lactose in less than 40 min.
mesh_terms: D000818:Animals; D005696:Galactosidases / Q000378:metabolism*; D005697:Galactosides / Q000378:metabolism*; D006027:Glycosides / Q000378:metabolism*; D006868:Hydrolysis; D007440:Intubation / Q000295:instrumentation; D007700:Kinetics; D007785:Lactose / Q000378:metabolism; D008892:Milk / Q000378:metabolism; D009598:Nitrophenylgalactosides / Q000378:metabolism; D009757:Nylons
chemical_list: D005697:Galactosides; D006027:Glycosides; D009757:Nylons; D009598:Nitrophenylgalactosides; D005696:Galactosidases; D007785:Lactose