title: A new strategy for improved glutathione production from Saccharomyces cerevisiae: use of cysteine- and glycine-rich chicken feather protein hydrolysate as a new cheap substrate.
abstract: BACKGROUND
  Glutathione (GSH) is composed of the amino acids glutamic acid, cysteine and glycine. This study investigated the usability of chicken feather protein hydrolysate (chicken feather peptone, CFP) as a substrate for GSH production from Saccharomyces cerevisiae.
  
  
  RESULTS
  CFP was found to be rich in ash (36.7 g per 100 g), protein (61.1 g per 100 g) and minerals (S, P, K, Ca, Fe, Na and Mg). It also had high contents of cysteine and glycine. CFP augmented biomass and GSH production by 53 and 115% respectively compared with the control medium. The highest biomass (17.4 g l(-1)) and GSH (271 mg L(-1)) concentrations were attained in CFP medium. The second highest biomass (16.8 g l(-1)) and GSH (255 mg L(-1)) concentrations were obtained in fish peptone medium. It was assumed that the high mineral, cysteine and glycine contents of CFP were related to cell growth and GSH synthesis in S. cerevisiae.
  
  
  CONCLUSIONS
  This is the first report on the effect of cysteine- and glycine-rich protein hydrolysates on GSH production from S. cerevisiae. In this regard, CFP was tested for the first time as a GSH production substrate. As an additional contribution, a new hydrolysis process was developed for the preparation of protein hydrolysates.
authors.affiliation: Department of Molecular Biology and Genetics, Science Faculty, Ataturk University, 25240 Erzurum, Turkey. mesuttaskin61@hotmail.com
authors.forename: Mesut
authors.initials: M
authors.lastname: Taskin
mesh_terms: D000818:Animals; D002645:Chickens; D003365:Costs and Cost Analysis; D003545:Cysteine / Q000032:analysis / Q000378:metabolism*; D005241:Feathers / Q000737:chemistry*; D005978:Glutathione / Q000096:biosynthesis* / Q000191:economics; D005998:Glycine / Q000032:analysis / Q000378:metabolism*; D006868:Hydrolysis; D008903:Minerals / Q000032:analysis; D010461:Peptones / Q000378:metabolism; D011492:Protein Hydrolysates / Q000737:chemistry* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
chemical_list: D008903:Minerals; D010461:Peptones; D011492:Protein Hydrolysates; D005978:Glutathione; D003545:Cysteine; D005998:Glycine