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1.
Braz. arch. biol. technol ; 55(5): 647-652, Sept.-Oct. 2012. ilus, tab
Article in English | LILACS | ID: lil-651646

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.

2.
Braz. arch. biol. technol ; 55(3): 465-470, May-June 2012. ilus, tab
Article in English | LILACS | ID: lil-640198

ABSTRACT

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.

3.
Braz. arch. biol. technol ; 52(2): 457-464, Mar.-Apr. 2009. ilus, graf, tab
Article in English | LILACS | ID: lil-513267

ABSTRACT

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 2² 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 percent of bromelain activity was recovered. Ultra-filtration retained 100 percent 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.


A concentração do suco de abacaxi é necessária para manter a atividade da bromelina e padronizar a composição e atividade proteolítica. Assim, este trabalho objetivou a obter um extrato de bromelina pura do suco do Ananas comosus L. Merril por processos de separação por membranas. Um planejamento experimental do tipo 2² foi feito para estudar a influência do pH a da pressão transmembranar sobre a recuperação da atividade por micro-filtração usando uma membrana plana. Em uma segunda etapa, purificou-se a enzima alvo por ultra-filtração usando um "kit millipore" de 10 kDa. A melhor condição para a concentração da bromelina foi a pH 7,5 e pressão transmembranar de 0,05 bar, onde 85 por cento da atividade da bromelina foi recuperado. A ultra-filtração manteve 100 por cento da atividade proteolítica e concentrou em 10 vezes o extrato de bromelina. A eletroforese via SDS-PAGE mostrou que o ultra-filtrado teve alta pureza e a bromelina da polpa do Ananas comosus tem um peso molecular de 24.5 kDa.

4.
Braz. arch. biol. technol ; 50(4): 713-718, July 2007. graf, tab
Article in English | LILACS | ID: lil-464344

ABSTRACT

This work aimed to study the pH and the transmembrane pressure effects during the recovery of alpha and beta amylases enzymes from corn malt (Zea mays) by hollow fiber membrane. The optimal condition was obtained for a statistical model, established by response surface methodology (RSM). The response surface analysis showed that the best operation condition for amylolitics enzymes recovery by hollow fiber membrane was 0.05 bar and pH 5.00, while the enzymes were purified about of 26 times.


Este trabalho objetivou estudar o efeito do pH e da pressão trans-membrana durante a recuperação das enzimas alfa e beta amilases do malte de milho (Zea mays) por membranas de fibras ocas, a obtenção das condições ótimas foi feita por um modelo estatístico, estabelecido pela metodologia de superfície de resposta (RSM). A análise da superfície de resposta mostrou que as melhores condições operacionais para a recuperação das enzimas amiloliticas por membranas de fibras ocas foi 0,05 bar e pH 5,00; onde as enzimas foram purificadas cerca de 26 vezes.

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