Decomposition of Chloro-organic Acids by Fungi

Abstract

DURING a study of bacterial decomposition of various chloro-substituted organic acids¹ it was observed that certain strains of Trichoderma viride produced small amounts of chloride in synthetic medium with sodium monochloroacetate as sole organic constituent. Extra addition of yeast or soil extract had little effect; but later experiments showed that the fungi became very active when glucose was supplied as an additional carbon source. Ten strains of T. viride were tested in liquid medium containing 0.04 M sodium monochloroacetate, 0.2 per cent glucose, 0.05 per cent ammonium sulphate and dipotassium phosphate, 0.02 per cent magnesium sulphate and calcium sulphate, and 0.005 per cent ferrous sulphate. Cultures were incubated at 25° C., and chloride was determined by titration with 0.01 N silver nitrate, in the presence of potassium chromate as an indicator. The strains proved to comprise two groups, each of five strains. One of these groups (I) was strongly and the other (II) weakly active towards monochloroacetate. In addition, dichloroacetate was decomposed with moderate vigour, but α-monochloropropionate only feebly (Table 1).