Production of galacto-oligosaccharide from lactose by Sterigmatomyces elviae CBS8119

• Published in: Applied and Environmental Microbiology Vol. 61; no. 11; pp. 4022 - 4025
• Main Authors: Onishi, N. (Ajinomoto Co. Inc., Kawasaki-shi, Japan.), Yamashiro, A, Yokozeki, K
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01.11.1995
• Subjects: Bacteria; Bacteria - metabolism; Bifidobacterium - metabolism; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; BIOSINTESIS; BIOSYNTHESE; Biotechnology; Carbohydrate Sequence; Cellular biology; DEUTEROMYCOTINA; FERMENTACION; FERMENTATION; Fundamental and applied biological sciences. Psychology; Glucose - pharmacology; Humans; Intestines - microbiology; LACTOSA; LACTOSE; Lactose - metabolism; LEVADURA; LEVURE; Magnetic Resonance Spectroscopy; METABOLISME DES GLUCIDES; METABOLISMO DE CARBOHIDRATOS; Mission oriented research; Mitosporic Fungi - drug effects; Mitosporic Fungi - metabolism; Molecular Sequence Data; OLIGOSACARIDOS; OLIGOSACCHARIDE; Oligosaccharides - biosynthesis; Oligosaccharides - chemistry; Physiology and metabolism; Trisaccharides - biosynthesis; Trisaccharides - chemistry; Yeast; Yeasts - metabolism; Yeast; Enzyme; Oligosaccharide; Selection; Toluene; Environmental factor; Identification; Fermentation; Fungi; Screening; Lactose; Chemical treatment; Glycosidases; Production; Hydrolases; Fungi Imperfecti; Microorganism; Galactose; O-Glycosidases; Trisaccharide; β-Galactosidase; Thallophyta; Structural analysis; Enzymatic reaction
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/aem.61.11.4022-4025.1995

Our stock cultures were screened for microorganisms that can produce galacto-oligosaccharide (Gal-OS) from lactose. Of the 574 strains of bacteria and yeasts tested, Sterigmatomyces elviae CBS8119, Rhodotorula minuta IFO879, and Sirobasidium magnum CBS6803 were found to be efficient producers of Gal-OS from lactose and S. elviae CBS8119 was selected as a representative, high-level producing strain. With toluene-treated resting S. elviae CBS8119 cells, 135 mg of Gal-OS per ml was produced from 360-mg/ml lactose. During this reaction, the by-product glucose was found to inhibit Gal-OS production. Therefore, in order to remove the glucose from the reaction mixture, a culture method in which cell growth followed the enzymatic reaction was devised, which increased the yield of Gal-OS considerably because of the consumption of glucose for cell growth. Under such conditions, 232 mg of Gal-OS per ml was produced from 360-mg/ml lactose after incubation at 30 degrees C for 60 h. The structure of the major product was identified as O-beta-D-galactopyranosyl-(1 leads to 4)-O-beta -D-galactopyranosyl-(1 leads to 4)-D-glucopyranose (4'-galactosyl-lactose) by 13C nuclear magnetic resonance spectroscopy