The concentration of pineapple juice is needed to retain the bromelain activity and to standardize the composition and proteolytic activity. Thus, this work aimed to obtain a pure bromelain extract from the Ananas comosus L. Merril juice by membrane separation process. A 2 2 experimental planning was used to study the influence of pH and transmembrane pressure on the activity recovery by micro-filtration using a plain membrane. In second step, this enzyme was purified by the ultra-filtration using a 10 kDa millipore kit. The best operation condition to bromelain concentration using the plain membrane was at pH 7.5 and transmembrane pressure of 0.05 bar, while 85% of bromelain activity was recovered. Ultra-filtration retained 100% of proteolytic activity and concentrated in 10 fold the bromelain extract. SDS-PAGE electrophoresis showed that the ultra-filtrated had high purity and the bromelain from A. comosus pulp had a molecular weight of 24.5 kDa.

ABSTRACT

This study aimed to obtain the condition of maximum bromalein activity in different parts of pineapple plants produced in vitro, by micropropagation. The sStems and leaves of Pérola and Imperial cultivar plants were evaluated after three and eight months of in vitro cultivation in Murashige and Skoog medium without growth phytoregulator, macerated in potassium phosphate buffer at different pH values (5.7, 6.7 and 7.7). Total protein and proteolytic activity were determined in the samples after three- and eight-month cultivation periods. For both the cultivars, the best results were obtained at pH 5.7 in extraction media. Pérola cultivar, showed higher bromelain activity in the leaves cultivated in vitro for three months (0.0194U/mL) while in the Imperial cultivar, it was higher in the stem after eight months (0.0179 U/mL). Imperial cultivar showed higher bromelain activity than the Pérola's

The aim of this work was to study the production of e bromelain from the Ananas comosus L. Merril, by determining the process conditions using flat membranes. The production system modeling generated a hyperbolical curve and the optimization by response surfaces showed an influence of the transmembrane pressure higher than the pH influence. The cost of the production of bromelain from A. comosus was estimated 9 to 13 times lower than Sigma's retail sales price and 6.5 to 8.5 times lower than when this enzyme was obtained through a liquid-liquid extraction, which showed the economical feasibility of the process.

O processo de separação por membrana é utilizado para recuperar, concentrar e até purificar macromoléculas. Um dos principais fatores limitantes nos processos de separação por membranas é o declínio do fluxo de permeado no decorrer do processo associado a fenômenos como a polarização por concentração, adsorção e fouling. O Ananas comosus L. Merril é uma fonte da enzima bromelina (EC 3.4.22.5), protease de alto valor comercial que não é produzida no Brasil. Neste trabalho, procura-se estudar os parâmetros que ocasionam o declínio do fluxo de permeado durante a recuperação da enzima bromelina, por meio da microfiltração tangencial do suco do Ananás comosus, utilizando membranas planas e de fibras ocas. Os resultados mostraram que a recuperação dessa enzima em pH neutro minimizou os efeitos da adsorção de proteínas e o aumento da pressão de operação contribuiu para o do fouling e para a desnaturação da enzima.