title: Production of bacterial cellulose by Gluconacetobacter hansenii CGMCC 3917 using only waste beer yeast as nutrient source.
abstract: In order to improve the use of waste beer yeast (WBY) for bacterial cellulose production by Gluconacetobacter hansenii CGMCC 3917, a two-step pre-treatment was designed. First WBY was treated by 4 methods: 0.1M NaOH treatment, high speed homogenizer, ultrasonication and microwave treatment followed by hydrolysis (121°C, 20 min) under mild acid condition (pH 2). The optimal pre-treatment conditions were evaluated by the reducing sugar yield after hydrolysis. 15% WBY treated by ultrasonication for 40 min had the highest reducing sugar yield (29.19%), followed by NaOH treatment (28.98%), high speed homogenizer (13.33%) and microwaves (13.01%). Treated WBY hydrolysates were directly supplied as only nutrient source for BC production. A sugar concentration of 3% WBY hydrolysates treated by ultrasonication gave the highest BC yield (7.02 g/L), almost 6 times as that from untreated WBY (1.21 g/L). Furthermore, the properties of the BC were as good as those obtained from the conventional chemical media.
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, No. 28 Xinong Road, 712100 Yangling, Shaanxi, China. Electronic address: lindehui504@hotmail.com.
authors.forename: Dehui
authors.initials: D
authors.lastname: Lin
authors.forename: Patricia
authors.initials: P
authors.lastname: Lopez-Sanchez
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.forename: Zhixi
authors.initials: Z
authors.lastname: Li
mesh_terms: D000042:Absorption; D001515:Beer / Q000382:microbiology*; D002482:Cellulose / Q000096:biosynthesis* / Q000648:ultrastructure; D041821:Gluconacetobacter / Q000378:metabolism*; D006868:Hydrolysis; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D002482:Cellulose
keywords: Bacterial cellulose; Gluconacetobacter hansenii; Pre-treatment; Property; Waste beer yeast