Abstract:For the detection of poly (malic acid) fermentation broth, a reversed phase high performance liquid chromatography method was developed. The samples was analyzed on a column of AlltimaTM C18 (4.6 mm×150 mm, 4 μm) with a mixture of acetonitrile and 0.025 mol/L KH2PO4 buffer (pH 2.5) (5:95, v:v) used as mobile phase at the flow rate of 1.0mL/min. The detection wavelength was 210 nm; the column temperature was 25 ℃ and the volum of injection was 5 μL. Before sampling, the fermentation broth was centrifuged to remove fungis, added with organic solvent to remove polysaccharide and hydrolysed. L-malic acid were completely separated and determined in 3 minutes. The recovery and relative standard deviation (RSD, n=3) of L-malic acid by RP-HPLC method were 98.70%~100.65%, and 0.40%~1.11%, respectively. The recovery and relative standard deviation (RSD, n=3) of L-malic acid by L-malic acid kit were 96.70%~97.23% and 0.57%-1.19%, respectively. The method was proved to be a effective way to determine the poly (malic acid) in fermentation broth.
