Resumo

Incorporation of enzymes in products and processes is a growing tendency. To equilibrate demand, availability and cost it is necessary to improve the fermentations and study the producing strains. This work aimed to evaluate growth and enzyme production (lipases, cellulases, amylases) by new Penicillium sp. isolates. Growth and sporulation of strains T9.1 and T10.5 were analyzed in agar Czapek, Vogel Minimal Medium (MMV), potato dextrose agar (PDA) and yeast extract glucose agar (YAG) for 21 days at room temperature and 30 ºC. Growth was also determined in media supplemented with glucose, starch, carboximetilcellulose, glycerol, soy and olive oils. Enzyme activities were determined for 7 days by revealing the zone of substrate degradation in solid media, and expressed as enzyme ratios (ER = enzyme activity zone/ colony diameter). All experiments were done at least in triplicate. Penicillium sp. T9.1 grew better in MMV at room temperature, and its sporulation was intense after 7 days of cultivation in this condition. Cellulase activity of strain T9.1 (ER^cel = 1.0; 2 dias; IE^cel = 1.7; 4 dias) was higher than its lipase (ER^lip = 1.0; 3 days, soy oil; ER^lip = 1.0; 4 days, soy oil) and amylolitic (ER^am = 1.0; 7 days) activities. Soy oil induced the lipase activity earlier (3 days) than olive oil (4 days). Among all substrates, glycerol supported the highest growth of strain T9.1, followed by soy oil. Maximum growth and sporulation (14 days) of Penicillium sp. T10.5 occurred in PDA at 30º C. ER^lip of strain T10.5 was similar to that of T9.1, however, its lipase activity was induced only after 4 days by soy and olive oils. Strain T10.5 showed a higher ER^am (1.2; 4 days) whereas its expression was faster (ER^am = 0.98; 3 days) than that of T9.1 (ER^am = 0.5; 4 days). Thus, T9.1 and T10.5 presented remarkable differences regarding requirements for growth and sporulation, such important information to produce inoculum for fermentation processes. According to the results, strain T10.5 may be more adequate for amylase production, while T9.1 showed perspective for lipase and cellulase production in shorter fermentations. Thus, studying the growth and potential of two new Penicillium sp. isolates provided essential knowledge to further develop and adjust fermentation processes for enzyme production.