Characterization of Microbes Degrading Organic Acids of Peatsoils

Abstract

The aim of the study was to isolate and characterize the growth of low pH tolerant-microbes being able to degrade and utilize organic acid extracted from peatsoil. Among 39 strains of fungi, bacteria and yeast isolated from various sources that grown at pH 3.8, strain FS2 was found to be the best isolate to degrade organic acid including p-hydroxybenzoic acid and increase pH-medium up to 5.9 within 36 hour. The optimum degradation of organic acid and pH increment were achieved when FS2 was grown on the medium containing 33.1 mN-NaOH organic acid, 2 g/l (NH4)2SO4, 0.5 g yeast extract, 1 g/liter KH2PO4, and 0.5 g/l MgSO47H2O at initial pH of 3.8. The maximum growth rate as observed by rate of organic acid comsumption and its pH increment were achieved at 6 to 12 hour of fermentation. The results revealed that an acid-tolerant strain FS2 was a prominent strain that is able to degrade organic acid and subsequently increase pH at high rate.