VARIATION OF LIPOLYTIC ACTIVITY IN THE GENUS ACINETOBACTER

Abstract

Four Acinetobacter isolates (SY1, SYD, BO2, IB2) were studied concerning lipolytic activity titrated on olive oil, biomass production, temperature and culture medium agitation. Fractionation of enzyme production was also investigated, as well as the effects of various temperatures on reaction speed and stability after heating. Finally, a series of substrates were tested so as to determine various capacities for lipid degradation. The biomass production was approximately identical for SY1, SYD and BO2 but slightly lower for IB2. On the other hand, lipolytic activity on olive oil was very variable among isolates, SY1 being the outstanding one in this field. As for temperature, SY1 and SYD had a maximum activity at 25°C and their enzymes were shortly degraded by heating, while BO2 and IB2 had a maximum activity at 45-50°C. All isolates were able to hydrolyze various substrates in the form of solution or emulsion, which warrants efficiency in the biodegradation of fats in wastewater treatment.