This review paper provides an overview regarding the main aspects of microbial lipases production. The most important microbial lipase-producing strains for submerged and solid-state fermentations are reviewed as well as the main substrates, including the use of agroindustrial residues. Current process techniques (batch, repeated-batch, fed-batch, and continuous mode) are discussed and the main bioreactors configurations are also presented. Furthermore, the present review paper shows a general overview about the development of mathematical models applied to lipase production. Finally, some future perspectives on lipase production are discussed with special emphasis on lipase engineering and the use of mathematical models as a useful tool for process improvement and control.

No abstract

Current studies about lipase production by solid-state fermentation involve the use of agro-industrial residues towards developing cost-effective systems directed to large-scale commercialization of enzyme-catalyzed processes. In this work, lipase production and partial characterization of the crude enzymatic extracts obtained by Penicillium verrucosum using soybean bran as substrate was investigated. Different inductors were evaluated and the results showed that there is no influence of this variable on the lipase production, while temperature and initial moisture were the main factors that affected enzyme production. The optimized cultivation temperature (27.5 degrees C) and initial moisture of substrate (55%) were determined using the response surface methodology. Kinetics of lipase production was followed at the optimized growth conditions. Optimum lipase yield was 40 U/g of dry bran. The crude enzymatic extract showed optimal activity in the range from 30 to 45 degrees C and in pH 7.0.

No abstract

This work was aimed at producing inulinase by solid-state fermentation of sugarcane bagasse, using factorial design to identify the effect of corn steep liquor (CSL) and soybean bran concentration, particle size of bagasse and size of inoculum. Maximum inulinase activity achieved was 250 U per g of dry substrate (gds) at 20% (w/w) of CSL, 5% (w/w) of soybean bran, 1 x 10(10) cells mL(-1) and particle size of bagasse in the range 9/32 mesh. The use of soybean bran decreased the time to reach maximum activity from 96 to 24 h and the maximum productivity achieved was 8.87 U gds(-1) h(-1). The maximum activity was obtained at pH 5.0 and 55.0 degrees C. Within the investigated range, the enzyme extract was more thermostable at 50.0 degrees C, showing a D-value of 123.1 h and deactivation energy of 343.9 kJ gmol(-1). The extract showed highest stability from pH 4.5 to 4.8. Apparent K(m) and V(max) are 7.1 mM and 17.79 M min(-1), respectively.

The essential oil of Eucalyptus sp. presented insecticidal and repellency against Sitophilus zeamais Motschulsky (Coleoptera, Curculionidae). Although from an economic point of view synthetic chemicals are still more frequently used as repellents, natural products (essential oils) have the potential to provide efficient and safer repellents for humans and the environment.

This work aimed at evaluating the conditions of growth and the recovery of total carotenoids produced by Sporidiobolus salmonicolor (CBS 2636). Optimization of carotenoid production was achieved by experimental design technique. A Plackett-Burman design was used, followed by a complete second-order design, to optimize the concentration of total carotenoids in a conventional medium. Maximum concentration of 1,019 μg l −1 of total carotenoids was obtained in a medium containing 40 g l −1 glucose, 10 g l −1 malt extract, and 14 g l −1 peptone, at 180 rpm, 25°C, and initial pH of 4.0. So far, no previous systematic study using microorganisms of the genus Sporobolomyces (formerly Sporidiobolus) for production of carotenoids has been reported. In this study, very good yields of carotenoids (1 mg l −1 ) could be obtained after optimization of fermentation medium and operation conditions.

No abstract