title: Transgalactosylation of lactose for synthesis of galacto-oligosaccharides using Kluyveromyces marxianus NCIM 3551.
abstract: Among a number of yeast strains screened for whole cell transgalactosylating activity, Kluyveromyces marxianus NCIM 3551 was found to be most suitable biocatalyst for production of galacto-oligosaccharides (GOS). Cell permeabilization lead to an efficient bioconversion by β-galactosidase resulting in synthesis of GOS. A maximum GOS yield of 36% (w/w) of total sugars was achieved and the products consisted of tri- and tetra-galacto-oligosaccharides. A lactose conversion rate of 80% and productivity of 24g/L/h was obtained under the optimum conditions at lactose concentration of 20% (w/v), temperature 40°C, pH 6.5 and enzyme units after 3h of reaction time. Tetrasaccharides were the main component of the reaction mixture. The products were quantitated by HPLC and structurally characterized by mass spectrometry.
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New-Delhi 110016, India. Electronic address: anitasri27@gmail.com.
authors.forename: Anita
authors.initials: A
authors.lastname: Srivastava
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New-Delhi 110016, India.
authors.forename: Saroj
authors.initials: S
authors.lastname: Mishra
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New-Delhi 110016, India.
authors.forename: Subhash
authors.initials: S
authors.lastname: Chand
mesh_terms: D001230:Aspergillus / Q000201:enzymology; D001711:Biotransformation / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D005690:Galactose / Q000096:biosynthesis*; D006031:Glycosylation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007716:Kluyveromyces / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism* / Q000494:pharmacology; D009844:Oligosaccharides / Q000096:biosynthesis*; D021241:Spectrometry, Mass, Electrospray Ionization; D013696:Temperature; D013997:Time Factors; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D009844:Oligosaccharides; D001616:beta-Galactosidase; D007785:Lactose; D005690:Galactose