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In this study, the kinetic of lipopeptide biosurfactant production by Bacillus subtilis LAMI005 and its tensoactive and emulsifier properties were evaluated. The influence of the concentrations of nitrogen ((NH4)2SO4) and carbon source (glucose and fructose) on biosurfactant production, using a mineral medium, were evaluated. A production of about 930 mg · L−1 of surfactin was observed for mineral medium supplied with total reducing sugars (16.55 g · L−1) and (NH4)2SO4 (1 g · L−1) as carbon and nitrogen sources, respectively. The crude biosurfactant exhibited its potential as tensoactive, presenting the capability to reach surface tension of about 28 mN ⋅ m−1 for water and exhibiting low CMC (~14–20 mg · L−1). The analysis of emulsifying activity showed a greater stability of emulsion formed in motor oil (3.5 U), soybean oil (2.0 U), and biodiesel (1.5 U). The emulsion formulated on motor oil remained stable for more than 200 h, which was explained by its average drop diameter (~0–10 μm). The surface‐active properties of surfactin did not seem to be affected by different NaCl concentrations, which may promote its applicability in high salt environments, such as oil spills in marine areas.

RESUMO -Apesar das vantagens e aplicabilidade, os maiores entraves da produção de biossurfactantes em larga escala residem nos elevados custos de produção. Substratos (meio de cultivo) equivalem a 30% dos custos de produção de biossurfactantes. A utilização de resíduos agroindustriais como substratos apresentam algumas vantagens como redução de custos no processo de produção dos biossurfactantes, além de reduzir possíveis impactos destes resíduos se fosse aplicados ao meio ambiente. O objetivo deste estudo visa avaliar substratos de baixo custo para a produção de biossurfactante como glicerol, soro de leite, suco de caju clarificado e óleo de girassol. Substratos como óleo de girassol e glicerol são apresentados como potenciais fontes de carbono para produção de biossurfactante pela cepa ICA56, obtendo concentrações de 870 mg.L -1 e 1420 mg.L -1 do produto de interesse, na sua forma bruta, respectivamente.

Semi-synthetic beta-lactam antibiotics are the most important class of antibacterial agents. Their use in veterinary and human medicine is in continuous expansion. Calcium phosphate bioceramics have been used in medicine and dentistry for nearly 30 years. Calcium phosphate ceramics (CPC) are nowadays being widely used as drug delivery systems because of their desirable properties such as biocompatibility, bioresorbability, controlled release etc. In recent years In this work, kinetic models to describe ampicillin adsorption from CPC were investigated. Calcium phosphate bioceramic are analogous to the mineral component of bones, its properties make it suitable for implant materials and delivery agents of drugs

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