Safety evaluation of phosphodiesterase derived from Leptographium procerum

5'-Phosphodiesterase is produced by fermentation of the fungus Leptographium procerum and is used to hydrolyse yeast RNA to produce flavour enhancers. To establish the safety in use of this enzyme preparation a number of studies have been performed: analysis for the potential of the production strain to produce toxic secondary metabolites, 28-days oral toxicity study of the preparation in the rat, bacterial mutation assay and in vitro mammalian chromosome aberration test in human lymphocytes. The production strain did not produce any secondary metabolites that may be of significance in food. Administration of dosage levels of 1250, 2500 and 5000 mg/kg body weight/day to rats for 28 day did not result in any toxicological significant changes. The enzyme preparation showed no mutagenic activity in the bacterial mutation assay and no clastogenic potency in an in vitro test. These results together with existing knowledge of the production organism and the chemical and microbiological characterisation of the enzyme preparation lead to the conclusion that the enzyme preparation containing 5'-phosphodiesterase activity from Leptographium procerum can safely be used for the production of flavour enhancers from bakers yeast at the anticipated intake levels for these uses.