Effect of Ensilaging and Organic Solvent Treatment on Activity of Proteases from Chicken Intestine

Studies were carried out to assess the extractability
of proteins from chicken intestine and to determine
the activity of proteases in crude extract. Further, the
activity of proteases was evaluated in acid and fermented
chicken intestinal silage as well as in organic solventtreated
intestinal samples. Extractability of proteins was in
the range of 3.85–4.06 mg/ml and was not affected (p≥
0.05) by the four different extractants, viz., distilled water,
phosphate buffer, and 1% potassium chloride with or
without 0.1 M Na2EDTA. The specific activity of acidic
and alkaline proteases were in the range of 4.78–7.26 and
19.31–24.07 units, respectively, and was not affected (p≥
0.05) by the type of extractant used. The pH profile for
activity showed higher activity in the alkaline pH range.
Addition of acid or ingredients for fermentation reduced the
extractability of protein significantly (p≤0.05). During
storage of silage, the reduction in enzyme activity was
higher in acid silage compared with fermented silage.
Treatment of chicken intestine with organic solvents
enhanced the enzyme activity and higher increase was
observed with isopropyl alcohol-treated intestine. During
storage of solvent-treated powders up to 3 months, the
activity of proteases reduced in all the solvent-treated
samples highest being in acetone-treated powder.