ISOLATION OF LIPASE-PRODUCING MICROORGANISMS TO OBTAIN BIODIESEL IN MÉXICO

Abstract

Microorganisms that produce lipases are generally known as lipolytic, and can be found in different habitats, such as plant and soil residues. This indicates that the same environment offers a wide potential for the isolation of new sources of lipases with novel properties. In this sense, the search for optimal conditions for their growth and exploitation is essential. The capacity for colony formation in soil samples from Chiapas, México, was evaluated, which were inoculated with three different levels of dilution in two culture mediums (nutritional medium and Potato Dextrose Agar), each one with a pH adjustment of 4, 7, and 9, and incubation temperatures of 20, 30, and 40 °C. The best combination of factors was
validated in 40 soil samples from 10 localities. The optimal condition which favored the growth of microorganisms in the soil sample was nutritional medium, with pH 7, incubation at 30 °C, and dilution factor of 1:1000. A marked effect of the soil collection site on the UFC average was identified. The collection sites from the municipality of Pijijiapan, Chiapas, presented the highest UFC averages, isolating 75 lipolytic colonies, of which 60 % were chemically characterized as Gram positive.