The polyphenoloxidase activity of nine bean (Phaseolus vulgaris L.) cultivars (Aruã, Aporé, A774, Carioca, Diamante Negro, Ouro Branco, Pérola, RAO 33 e Rudá) were studied. The crude enzyme extract of the nine cultivars was found to have optimum pH in 7.2 using catechol as substrate. No PPO activity in beans (Phaseolus vulgaris L.) was observed using D,L DOPA and gallic acid as substrate.
gallic acid; catechol; D,L-DOPA; beans; pyrogallol; polifenoloxidase