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bioRxiv · 10.1101/2020.07.24.220400

Development and validation of an HPLC method to quantify 2-Keto-3-deoxy-gluconate (KDG), a major metabolite in pectin and alginate degradation pathways

Martis B, S.·Droux, M.·Deboudard, F.·Nasser, W.·Meyer, S.·Reverchon, S.
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Abstract

A rapid and sensitive High Performance Liquid Chromatography (HPLC) method with photometric and fluorescence detection is developed for routine analysis of 2-Keto-3-deoxy-gluconate (KDG), a catabolite product of pectin and alginate. These polysaccharides are primary-based compounds for biofuel production and for generation of high-value-added products. HPLC is performed, after derivatization of the 2-oxo-acid groups of the metabolite with o-phenylenediamine (oPD), using a linear gradient of trifluoroacetic acid and acetonitrile. Quantification is accomplished with an internal standard method. The gradient is optimized to distinguish KDG from its close structural analogues such as 5-keto-4-deoxyuronate (DKI) and 2,5-diketo-3-deoxygluconate (DKII). The proposed method is simple, highly sensitive and accurate for time course analysis of pectin or alginate degradation. HighlightsA fluorescent based-HPLC method report the quantification of KDG, a metabolite originating from alginate and from pectin degradation pathways, using derivatization with o-phenylenediamine (oPD)

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Martis B, S., Droux, M., Deboudard, F., Nasser, W., Meyer, S., Reverchon, S.. 2020-07-25. Development and validation of an HPLC method to quantify 2-Keto-3-deoxy-gluconate (KDG), a major metabolite in pectin and alginate degradation pathways. https://doi.org/10.1101/2020.07.24.220400

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