title: Effective production of low crystallinity Poly(3-hydroxybutyrate) by recombinant E. coli strain JM109 using crude glycerol as sole carbon source.
abstract: Utilization of bio-diesel by-products (glycerol) for microbial polymer production has created a novel biorefinery concept. In the present study, recombinant Escherichia coli JM109 was used for the production of P(3 HB) from glycerol as carbon source. Batch fermentation in a 7.5L bioreactor with the statistically optimized culture condition (pre-treated glycerol: 27.5 g/L and casein hydrolysate: 5.25 g/L) scaled up the P3HB production to 65% (∼ 8 g/L). FTIR, (1)H and (13)C NMR analysis proved the polymer produced to be P(3 HB). Gel permeation chromatography, Differential Scanning Calorimetry (DSC) and thermogravimetric analysis (TGA) demonstrated the produced P(3 HB) to have high molecular weight (2.84 × 10(6)) and lowered crystallinity (∼ 30%) compared to commercial polymer. Integrating the production efficiency and the thermal characteristics of the polymer produced by recombinant E. coli, the viability and sustainability of biofuels and biopolymers for economic human need could be enhanced.
authors.affiliation: Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India.
authors.forename: Mohan
authors.initials: M
authors.lastname: Ganesh
authors.affiliation: Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India.
authors.forename: Arivazhagan
authors.initials: A
authors.lastname: Senthamarai
authors.affiliation: Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India.
authors.forename: Santhanam
authors.initials: S
authors.lastname: Shanmughapriya
authors.affiliation: Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India. Electronic address: natarajaseenivasan@rediffmail.com.
authors.forename: Kalimuthusamy
authors.initials: K
authors.lastname: Natarajaseenivasan
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D003460:Crystallization; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D024861:Genetic Enhancement / Q000379:methods*; D005990:Glycerol / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D008968:Molecular Conformation; D044367:Phase Transition; D011091:Polyesters / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics; D012037:Refuse Disposal / Q000379:methods; D013045:Species Specificity; D000094122:Polyhydroxybutyrates
chemical_list: D005990:Glycerol; D006885:Hydroxybutyrates; D011091:Polyesters; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates
keywords: Crystallinity index; Glycerol; Low crystallinity; P(3HB)