title: Economic co-production of poly(malic acid) and pullulan from Jerusalem artichoke tuber by Aureobasidium pullulans HA-4D.
abstract: poly(L-malic acid) (PMA) is a water-soluble polyester with many attractive properties in medicine and food industries, but the high cost of PMA fermentation has restricted its further application for large-scale production. To overcome this problem, PMA production from Jerusalem artichoke tubers was successfully performed. Additionally, a valuable exopolysaccharide, pullulan, was co-produced with PMA by Aureobasidum pullulans HA-4D.
  
  
  
  The Jerusalem artichoke medium for PMA and pullulan co-production contained only 100 g/L hydrolysate sugar, 30 g/L CaCO3and 1 g/L NaNO3. Compared with the glucose medium, the Jerusalem artichoke medium resulted in a higher PMA concentration (114.4 g/L) and a lower pullulan concentration (14.3 g/L) in a 5 L bioreactor. Meanwhile, the activity of pyruvate carboxylase and malate dehydrogenas was significantly increased, while the activity of α-phosphoglucose mutase, UDP-glucose pyrophosphorylase and glucosyltransferase was not affected. To assay the economic-feasibility, large-scale production in a 1 t fermentor was performed, yielding 117.5 g/L PMA and 15.2 g/L pullulan.
  
  
  
  In this study, an economical co-production system for PMA and pullulan from Jerusalem artichoke was developed. The medium for PMA and pullulan co-production was significantly simplified when Jerusalem artichoke tubers were used. With the simplified medium, PMA production was obviously stimulated, which would be associated with the improved activity of pyruvate carboxylase and malate dehydrogenas.
authors.affiliation: Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an, 223300, China. xiajun050219@126.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Xia
authors.affiliation: Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an, 223300, China.
authors.forename: Jiaxing
authors.initials: J
authors.lastname: Xu
authors.affiliation: Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an, 223300, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liu
authors.affiliation: Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an, 223300, China.
authors.forename: Jiming
authors.initials: J
authors.lastname: Xu
authors.affiliation: Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an, 223300, China.
authors.forename: Xingfeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Jiangsu Province Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huai'an, 223300, China.
authors.forename: Xiangqian
authors.initials: X
authors.lastname: Li
mesh_terms: D001203:Ascomycota / Q000235:genetics / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods; D005818:Genetic Engineering / Q000191:economics / Q000379:methods; D005936:Glucans / Q000191:economics* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006368:Helianthus / Q000235:genetics / Q000378:metabolism*; D008293:Malates / Q000191:economics* / Q000302:isolation & purification / Q000378:metabolism*; D035281:Plant Tubers / Q000235:genetics / Q000378:metabolism; D011108:Polymers / Q000191:economics* / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D005936:Glucans; D008293:Malates; D011108:Polymers; C121060:poly(malic acid); C009109:pullulan
keywords: Co-production; Enzyme activity; Jerusalem artichoke; Poly(malic acid); Pullulan