Table 1 - Enzymological characterization of pineapple extract for potential application in oak tasar (Antheraea proylei J.) silk cocoon cooking and reeling

Table 1: Comparison between the pineapple extract prepared in distilled water and that prepared in cocoon extract with respect to proteinase activity and thermal inactivation behaviour.

Pineapple extract		Proteinase activity (ΔAbs at 420 nm / 30 min)*		% Residual activity of thermal inactivation at 60ºC
Pineapple extract		At room temperature (26-31ºC)	At 60ºC	After 30 min incubation	After 60 min incubation
Pineapple extract prepared in distilled water	Without sodium carbonate	0.146	0.357	87.2	82.6
Pineapple extract prepared in distilled water	With 9.8 mM sodium carbonate	0.350	0.399	95.2	79.9
Pineapple extract prepared in cocoon extract	Without sodium carbonate	0.167	0.312	93.8	83.1
Pineapple extract prepared in cocoon extract	With 9.8 mM sodium carbonate	0.327	0.408	81.4	51.4

*The proteinase activity in pineapple extract was assayed by a modification of the azocasein method of Rowan and Buttle, 1994 described in Proteinase assay given in the text.

Pineapple extract