title: Efficient production of pullulan by Aureobasidium pullulans grown on mixtures of potato starch hydrolysate and sucrose.
abstract: Pullulan is a natural exopolysaccharide with many useful characteristics. However, pullulan is more costly than other exopolysaccharides, which limits its effective application. The purpose of this study was to adopt a novel mixed-sugar strategy for maximizing pullulan production, mainly using potato starch hydrolysate as a low-cost substrate for liquid-state fermentation by Aureobasidium pullulans. Based on fermentation kinetics evaluation of pullulan production by A. pullulans 201253, the pullulan production rate of A. pullulans with mixtures of potato starch hydrolysate and sucrose (potato starch hydrolysate:sucrose=80:20) was 0.212h-1, which was significantly higher than those of potato starch hydrolysate alone (0.146h-1) and mixtures of potato starch hydrolysate, glucose, and fructose (potato starch hydrolysate:glucose:fructose=80:10:10, 0.166h-1) with 100gL-1total carbon source. The results suggest that mixtures of potato starch hydrolysate and sucrose could promote pullulan synthesis and possibly that a small amount of sucrose stimulated the enzyme responsible for pullulan synthesis and promoted effective potato starch hydrolysate conversion effectively. Thus, mixed sugars in potato starch hydrolysate and sucrose fermentation might be a promising alternative for the economical production of pullulan.
authors.affiliation: Microbiology Institute of Shaanxi, Xi'an, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: An
authors.affiliation: Microbiology Institute of Shaanxi, Xi'an, PR China.
authors.forename: Sai-Jian
authors.initials: SJ
authors.lastname: Ma
authors.affiliation: Microbiology Institute of Shaanxi, Xi'an, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Chang
authors.affiliation: Microbiology Institute of Shaanxi, Xi'an, PR China. Electronic address: x-wenjiao@163.com.
authors.forename: Wen-Jiao
authors.initials: WJ
authors.lastname: Xue
mesh_terms: D001203:Ascomycota / Q000378:metabolism*; D061249:Batch Cell Culture Techniques; D018533:Biomass; D019149:Bioreactors; D002244:Carbon / Q000378:metabolism; D005285:Fermentation; D005936:Glucans / Q000096:biosynthesis*; D007700:Kinetics; D011198:Solanum tuberosum / Q000737:chemistry*; D013213:Starch / Q000737:chemistry / Q000378:metabolism*; D013395:Sucrose / Q000378:metabolism*
chemical_list: D005936:Glucans; D013395:Sucrose; D002244:Carbon; C009109:pullulan; D013213:Starch
keywords: Aureobasidium pullulans; Batch kinetics; Mixed sugar; Potato starch hydrolysate; Pullulan