Characterization of biotechnological processes and products using high‐performance liquid chromatography (HPLC). III. Quantitative analysis of organic acids in the α‐ketoglutaric acid synthesis

Abstract

A HPLC technique for the ancllys,is of organic acids in the production of a-ketoglutaric acid was developed. The method was applied and optimized for the quantitative determination of citric acid, pyruvic acid, iaocitric acid and a-ketoglutoric acid in fermentation solutions.As microorganism the yeast Yarroroia lipolytk and as substrates glucose or paraffins were used. The chromatographic separations were carried out by means of 50 and 1 0 0 x 8 m m i.d. glass columns packed with an anion-exchange resin based on an 8% cross-linked polystyrene-divinylbenzene copolymer. The relative errors ranged from 2.1% (a-ketoglutaric acid) to 5.2% (isocitric acid). The percent recovery values varied between 94.4% (isocitric acid) and 107.7% (pyruvic acid). The contents of organic acids in fermentation solutions after the microbial synthesis based on paraffins or glucose were compared.

Screening of a thiamine-auxotrophic yeast for α-ketoglutaric acid overproduction

“…The supernatant was diluted 50 times and filtered through a membrane (pore size = 0·22 μm). α‐KG and pyruvate were simultaneously determined by HPLC (Agilent 1100 series, Santa Clara, CA, USA) with a C18 column, StableBond (Shiseido Co. Ltd, Tokyo, Japan); with mobile phase, 0·1% phosphoric acid aqueous solution; flow rate, 1·0 ml min −1 ; column temperature, 28°C; injection volume, 10 μl; and detection, UV (210 nm) (Gey et al. 1988).…”

Characterization of biotechnological processes and products using high‐performance liquid chromatography (HPLC) VI. Determination of lactic acid and short‐chain carboxylic acids C1–C5

“…formic acid cannot be analyzed in small concentrations. More recently, HPLC has become the method of choice for simultaneous determinations of volatile and non-volatile organic acids [16--301 in biological samples [18,20,[28][29][30]. However, anion-exchange chromatography [22, 27, 281 used as a n effective and efficient method, e.g.…”

A simple and versatile system for fermentation control by on‐line HPLC analysis of medium components

“…-12,[16][17][18][19][20][21][22][23][24][25]. Before entering the analytical instrument, insoluble material and cells must be removed necessarily from the sample.…”