Produção, purificação e caracterização de a-galactosidase fungica. Hidrolise de oligossacarides do extrato de soja

AUTOR(ES)
DATA DE PUBLICAÇÃO

1983

RESUMO

The production, of α-galactcsidase by a strain of Aspergillus orizas was observed either by sub merged culture method or Koji method. The enzyme was slightly induced by raffinose and stacchyosef while in a previously fermented oligosaccharides extract from soybean with 3.7 per cent of total sugar the yield was greatly increased. The partially purified α-gaiactosidase showed a Km value of 2.04 and 140 mMole respectively for PNPG and melihiose. The Vm value was 0.36 µMole of PNP and 0.54 of glucose/rain/mg, of protein for the same substrates. The molecular weight was estimated in 200 000 by gel filtration in Sephadex G-200 and the enzyme was competitively inhibited by galactose and fructose and non competitively by glucose. Ag+, Hg+ and p-Chloromercuribenzoats remarkdly inhibited the enzyme activity suggesting the presence of SH groups in the active site. The optimum pH was 4,0 and more them 70% of the maximum activity was found in pH 6.3. No loss of activity was shown when submitted to heat treat: meant between 35 – 50º C, for 15 minutes. Enzymatic filtrate substantially de creased the contents of raffinose and stacchyose from soybean milk suggesting the possibility of its application to eliminate soybean galactooligosccharydes responsible for flatulence troubles.

ASSUNTO(S)

soja como alimento galactose oligossacaridio

ACESSO AO ARTIGO

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