Twenty-one bacterial isolates from soil and compost were obtained by extn. with H2O and used (also as mixts.) for biodegrdn. of fat wastes. The olive, rapeseed oil and lard wastes were treated with individual composite cultures to detn. their lipolytic activity at pH 5-9 and 28-50 degrees C. The mixed cultures were less active than the individual bacterial Isolates. Only the olive oil was better degraded by composites than by pure cultures.