title: Determination of dihydroxyacetone and glycerol in fermentation process by GC after n-methylimidazole catalyzed acetylation.
abstract: A gas chromatographic method that accurately measures glycerol and dihydroxyacetone from a fermentation broth is described in this paper. The method incorporates a sample derivatization reaction using n-methylimidazole as catalyst in the presence of acetic anhydride. Resulting derivatives are separated on a DB-5 capillary column and flame ionization detector. Results show that 10 μL n-methylimidazole and 75 μL acetic anhydride are sufficient to complete the acetylation for glycerol and dihydroxyacetone at room temperature for 5 min. The present method exhibits good linearity at a concentration range of 1-100 g/L with excellent regression (R(2) > 0.9997). The limits of detection are 0.025 and 0.013 g/L for dihydroxyacetone and glycerol, respectively. The method has been successfully applied to the monitoring and control of the fermentation process, and recoveries are in the range of 95.5-98.8% with relative standard deviations below 1%.
authors.affiliation: New Word Institute of Biotechnology, State Key Lab of Bioreactor Engineering, East China University of Science and Technology, 200237 Shanghai, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.forename: Ming-Hua
authors.initials: MH
authors.lastname: Li
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Lin
authors.forename: Dong-Zhi
authors.initials: DZ
authors.lastname: Wei
mesh_terms: D000089:Acetic Anhydrides / Q000737:chemistry; D000107:Acetylation; D002849:Chromatography, Gas / Q000379:methods*; D004098:Dihydroxyacetone / Q000032:analysis*; D005285:Fermentation; D020600:Gluconobacter oxydans / Q000737:chemistry; D005990:Glycerol / Q000032:analysis*; D007093:Imidazoles / Q000737:chemistry*; D016014:Linear Models; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013696:Temperature
chemical_list: D000089:Acetic Anhydrides; D007093:Imidazoles; C031800:acetic anhydride; D004098:Dihydroxyacetone; C018100:1-methylimidazole; D005990:Glycerol