The acid protease was isolated from the culture broth of the Penicillum sp. grown in the wheat bran media. 'quot;The crude purification of this enzyme was carried out by extraction with distilled water and precipitated with saturated ammonium sulfate....
The acid protease was isolated from the culture broth of the Penicillum sp. grown in the wheat bran media. 'quot;The crude purification of this enzyme was carried out by extraction with distilled water and precipitated with saturated ammonium sulfate. " The activity of this enzyme was found to be very strong by Folin′s colorimetric method. The results were as follows. 1. The optimum pH of the enzyme activity was at 3.0 and its optimum temperature was 5$0^{\circ}C$. 2. Although the enzyme activity to hydrolyze casein was maximal at 5$0^{\circ}C$, its activity decreased rapidly by about 50%, treated at 5$0^{\circ}C$ for 30 min. When treated at 4$0^{\circ}C$ for 60 min, the enzyme activity decreased to 75% of original value and did not decrease any more. 3. The enzyme was stable at pH 2.0 to 6.0. 4. This enzyme activity was not effected by metal ions; C $d^{++}$, Z $n^{++}$, $Co^{++}$, H $g^{++}$, M $n^{++}$, P $b^{++}$, $Mg^{++}$, L $i^{+}$, C $u^{++}$, $Ba^{++}$, A $g^{+}$, $Al^{+++}$, $Ca^{++}$, F $e^{++}$, and F $e^{++}$ 5. Also, it was not effected by treatemnt of EDTA.