ANTI-NUTRITIONAL CONSTITUENT OF COLOCASIA ESCULENTA ...

A.A.3 Enzyme trypsin
10 mg bovine-pancreas trypsin type I was dissolved in 0.001 M HCl. The enzyme was
stable in a refrigerator for two weeks.
100 mg protease was dissolved in 1 litre of tris-HCl buffer, pH 8.0, (i.e. a-ehymotrypsin
type vii from bovine pancreas, protease type xiv from Streptomyces Griseus, proteinase
type xviii from Rhizopus species and protease type xiii fungal from Aspergillus SaitOI).
A.A.4 0.001 M BAPNA (Benzoyl-DL-arginine-p-nitroaniline)
43.5 mg of benzoyl-DL-arginine-p-nitroaniline (BAPNA) was dissolved in I ml of
dimethyl sulfoxide (DMSO) solution. This was diluted to 100 ml with 0.05 M tris-HCl
buffer pH 8.6, containing 0.02 M calcium chloride. Care was taken to dissolve all BAPNA
in the DMSO, as the presence of any crystals causes precipitation to occur on standing. A
constant temperature was maintained throughout preparation.
A.A.5 Phosphate buffer pH 6.9
18.73 g of sodium dihydrogen orthophosphate and 8.15 g of disodium hydrogen
orthophosphate were mixed, dissolved together in a litre of distilled water and the pH was
adjusted to 6.9.
A.A.6 Soluble starch
1 gofsoluble starch was dissolved in 100 ml ofphosphate buffer.
A.A.7 Dinirrosalicylic acid (DNS)
1 g of3.5 dinitrosalicylic acid was dissolved in 20 ml of2 M NaOH and 50 ml of distilled
water. 30 g ofRochelle salt was added and made up to 100 ml with distilled water.
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