Lipase de Aspergillus niger foi imobilizada por deposição utilizando Celite e as atividades de hidrólise e esterificação, a estabilidade e a enantioseletividade das formas livre e imobilizada foram comparadas. Ambas as preparações mostraram propriedades bioquímicas similares, com atividade máxima em pH 6,0 e temperatura de 30-40 ºC. Não foram observadas diferenças na atividade hidrolítica em função do pH para as duas formas da enzima. Os efeitos mais importantes observados após a imobilização foram a estabilidade térmica e a melhoria da atividade de esterificação na reação do (R,S)-ibuprofeno com 1-propanol em presença do isooctano. Além disso, a lipase na forma imobilizada manteve, pelo menos, 73% de sua atividade de esterificação após 5 dias de armazenamento a 40 ºC e pôde ser reciclada e reutilizada por pelo menos 6 vezes.

Aspergillus niger lipase was immobilized by deposition on Celite and the hydrolytic and esterification activities, stability and enantioselectivity of both free and immobilized enzyme were compared. Both the free and immobilized preparations showed similar biochemical properties, with maximum activity at pH 6.0 and a temperature of 30-40 ºC. The most important effects observed when the lipase was immobilized were thermal stability and an improved esterification activity during the reaction of (R,S)-ibuprofen with 1-propanol in isooctane. Moreover, immobilized Aspergillus niger lipase maintained an esterification activity of at least 73% after 5 days of storage at 40 ºC and can be recycled and reused at least 6 times.

Given the inherent dangers associated with racemic pharmaceuticals, exhaustive studies of techniques designed to separate enantiomers have been conducted. This paper reports a brief review of the different physical, chemical, and enzymatic methods used for the enantiomeric separation of rac-ibuprofen. The possible contribution of each technique to the preparation of enantiomerically pure drugs is reviewed in the context of competitive approaches that depend on the scale of application, with special emphasis on the recent progress achieved in this particular area.