-This paper provides an overview regarding the main aspects of seed lipases, such as the reactions catalyzed, physiological functions, specificities, sources and applications. Lipases are ubiquitous in nature and are produced by several plants, animals and microorganisms. These enzymes exhibit several very interesting features, such as low cost and easy purification, which make their commercial exploitation as industrial enzymes a potentially attractive alternative. The applications of lipases in food, detergents, oils and fats, medicines and fine chemistry, effluent treatment, biodiesel production and in the cellulose pulp industry, as well as the main sources of oilseed and cereal seed lipases, are reviewed.

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The use of enzymes in juice industry has contributed in increasing the yield and production of various types of juices. The addition pectinases aims in particular to degrade the pectic substances, in the cell wall and middle lamella of the cells of plants, aiming to minimise the impacts of these compounds on the characteristics of the final product, such as colour, turbidity and viscosity. Enzymes able to remove bitterness of citrus juice, extract pigments, among other applications, have also had great interest in the juice industry.

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This study concerned the production, purification and application of extracellular chitinase from Cellulosimicrobium cellulans strain 191. In shaken flasks the maximum yield of chitinase was 6.9 U/mL after 72 h of cultivation at 25 o C and 200 rpm. In a 5 L fermenter with 1.5 vvm aeration, the highest yield obtained was 4.19 U/mL after 168 h of fermentation at 25 o C and 200 rpm, and using 3 vvm, it was 4.38 U/mL after 144 h of fermentation. The chitinase (61 KDa) was purified about 6.65 times by Sepharose CL 4B 200 gel filtration with a yield of 46.61%. The purified enzyme was able to lyse the cell walls of some fungi and to form protoplasts.

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Objective. To determine if acid-etched, cross-linked dentin can be dehydrated without lowering bond strength below that of cross-linked wet-bonded dentin in vitro.Methods. Using extracted human third molars, control acid-etched dentin was bonded with Single Bond Plus, using either the wet-or dry-bonding technique. Experimental acid-etched dentin was treated with 5 mass% grape seed extract (GSE) in different solvents for 1 min before undergoing wet vs dry resin-dentin bonding with Single Bond Plus. Completely demineralized dentin beams were treated with 5% GSE for 0, 1 or 10 min, before measuring stiffness by 3-point flexure. Other completely demineralized beams were treated similarly and then incubated in buffer for 1 week to measure the collagen solubilization by endogenous dentin proteases.Results. 24 h microtensile bond strengths (TBS) in wet and dry controls were 53.5 ± 3.6 and 9.4 ± 1.8 MPa, respectively (p < 0.05). 5% GSE in water gave TBS of 53.7 ± 3.4 and 39.1 ± 9.7 MPa (p < 0.05), respectively, while 5% GSE in ethanol gave TBS of 51.2 ± 2.3 and 35.3 ± 2.0 MPa (p < 0.05). 5% GSE in 5% EtOH/95% water gave wet and dry TBS of 53.0 ± 2.3 and 55.7 ± 5.1 MPa (p > 0.05). Cross-linking demineralized dentin with 5% GSE increased stiffness of dentin and decreased collagen degradation (p < 0.05).