title: Efficient production of free fatty acids from ionic liquid-based acid- or enzyme-catalyzed bamboo hydrolysate.
abstract: Two engineered Escherichia coli strains, DQ101 (MG1655 fadD-)/pDQTES and DQ101 (MG1655 fadD-)/pDQTESZ were constructed to investigate the free fatty acid production using ionic liquid-based acid- or enzyme-catalyzed bamboo hydrolysate as carbon source in this study. The plasmid, pDQTES, carrying an acyl-ACP thioesterase 'TesA of E. coli in pTrc99A was constructed firstly, and then (3R)-hydroxyacyl-ACP dehydratase was ligated after the TesA to give the plasmid pDQTESZ. These two strains exhibited efficient fatty acid production when glucose was used as the sole carbon source, with a final concentration of 2.45 and 3.32 g/L, respectively. The free fatty acid production of the two strains on xylose is not as efficient as that on glucose, which was 2.32 and 2.96 g/L, respectively. For mixed sugars, DQ101 (MG1655 fadD-)-based strains utilized glucose and pentose sequentially under the carbon catabolite repression (CCR) regulation. The highest total FFAs concentration from the mixed sugar culture reached 2.81 g/L by DQ101 (MG1655 fadD-)/pDQTESZ. Furthermore, when ionic liquid-based enzyme-catalyzed bamboo hydrolysate was used as the carbon source, the strain DQ101 (MG1655 fadD-)/pDQTESZ could produce 1.23 g/L FFAs with a yield of 0.13 g/g, and while it just produced 0.65 g/L free fatty acid with the ionic liquid-based acid-catalyzed bamboo hydrolysate as the feedstock. The results suggested that enzymatic catalyzed bamboo hydrolysate with ionic liquid pretreatment could serve as an efficient feedstock for free fatty acid production.
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Road 55, Shapingba District, Chongqing, 401331, People's Republic of China.|State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing, 210009, People's Republic of China.
authors.forename: Le
authors.initials: L
authors.lastname: Mi
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Road 55, Shapingba District, Chongqing, 401331, People's Republic of China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Qin
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Road 55, Shapingba District, Chongqing, 401331, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Cheng
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Road 55, Shapingba District, Chongqing, 401331, People's Republic of China. dwang@cqu.edu.cn.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing, 210009, People's Republic of China. lisha@njut.edu.cn.
authors.forename: Sha
authors.initials: S
authors.lastname: Li
authors.affiliation: College of food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
authors.forename: Xuetuan
authors.initials: X
authors.lastname: Wei
mesh_terms: D002241:Carbohydrates / Q000737:chemistry; D003470:Culture Media / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000096:biosynthesis*; D005285:Fermentation; D005947:Glucose / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*; D060847:Metabolic Engineering; D000074041:Microorganisms, Genetically-Modified; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D006109:Poaceae / Q000737:chemistry*; D013869:Thiolester Hydrolases / Q000235:genetics / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D003470:Culture Media; D029968:Escherichia coli Proteins; D005230:Fatty Acids, Nonesterified; D052578:Ionic Liquids; D013869:Thiolester Hydrolases; C018748:oleoyl-(acyl-carrier-protein) hydrolase; D005947:Glucose
keywords: Arabinose; Bamboo hydrolysate; Enzyme; Free fatty acids; Ionic liquid