Abstract
Brazil produces over than 70,000 ha of pineapple, being the world leader in pineapple production, and Minas Gerais State alone produces over than 600 kt/y. The pineapple is the marketable plant part, which represents only 23 % of the plant itself, and the remaining plant, stem, leaves, bark and crown, being considered an agroindustrial residue. This residue contains great amount of bromelain, a vegetable protease group with several applications in food and pharmaceutical industries, which has high market value. These enzymes performs important role in proteolytic modulation at cellular matrix, and in numerous physiologic processes, including tissue morphogenesis, tissue repair, angiogenesis and tissue modulation, decreasing bruises, swelling, pain and healing time. This work reports the ethanol fractional precipitation of bromelain from pineapple stem, bark and leaves, and its characterization after the recovery process. Aqueous extract of bromelain was prepared by processing pineapple’s stem, bark and leaves in a common juice extractor. Ethanol fractional precipitation studies were performed under refrigeration (4 °C), and it was carried out stepwise, where several concentrations of ethanol were added to perform a fractional precipitation. Bromelain was characterized before and after precipitation to determine its optimal pH, temperature and stability. Results showed that bromelain was precipitated successfully in the 30-70 % ethanol fraction, in which were achieved a purification factor of 2.07 fold and yielded over than 98 % of enzyme recovery. After the purification, the bromelain optimal pH changed from 7.0 to 8.0, and it kept activity even after 60 °C, however its optimum were 50 °C. These results showed that bromelain recovery with ethanol fractional precipitation is a viable process, in which results in a good quality enzyme for industrial applications.
