3.4.22.33	Ca2+	noncompetitive inhibition at pH 3.5, while both K-and V-type activations of bromelain are observed in the presence of 0.5 mM Ca2+ at pH 4.5 and pH 7.5	15	
3.4.22.33	Cu2+	12% residual activity at 0.16 mM	19	
3.4.22.33	Cu2+	inhibits casein degradation, complete inhibition	19	
3.4.22.33	Cu2+	reduces activity	19	
3.4.22.33	Cu2+	competitive inhibition at pH 3.5 with 0.6 mM Cu2+, which changes to an uncompetitive inhibition at pH 4.5 and pH 7.5	19	
3.4.22.33	cystatin	-	1600	
3.4.22.33	cystatin	an extended AE-rich N-terminal trunk in secreted pineapple cystatin enhances inhibition of fruit bromelain and is posttranslationally removed during ripening, The AE-rich N-terminal trunk is required to inhibit fruit bromelain (above 95%), whereas its removal decreases inhibition to 20%. Recombinant cystatin containing the complete AE-rich N-terminal trunk and recombinant medium pineapple cystatin effectively inhibit bromelain compared to recombinant core pineapple cystatin	1600	
3.4.22.33	Fe3+	reduces activity	70	
3.4.22.33	Hg2+	14% residual activity at 0.16 mM	33	
3.4.22.33	Hg2+	inhibits casein degradation, complete inhibition	33