Application of ionising radiation for the stabilisation of Trichoderma viride cellulases

Abstract

The solutions of cellulolytic enzymes designated as standards for the cellulase activity assay were exposed in sealed glass ampoules (containing at least 100 Cx-units per ml in 30% w/w glycerol) to gamma radiation within the dose interval of 0-18 kGy. Glycerol was found to be the best enzyme stabiliser, however, the dose for the decontamination had to be increased in comparison with the original solution because glycerol protected also the contaminating microflora. The preparation after such treatment (30% of glycerol, dose 7 kGy) retained about 95% of the initial enzymatic activity without any decrease taking place in the following 6 months. The loss of the side activities did not exceed 10.5% and no bacterial contamination was detected either after 6 months of storage following the irradiation. No difference was found in the immunoreactivity of cellulases or in protein chromatografic (FPLC) pattern between the original and the irradiated enzyme preparations.