Immobilization of Papain on Chitin and Chitosan and Recycling of Soluble Enzyme for Deflocculation of Saccharomyces cerevisiae from Bioethanol Distilleries

Table 5

Proteolytic activity of the papain in the presence of glutaraldehyde, polyethyleneimine, and tripolyphosphate, for 120 minutes at 27^°C.

Concentration (%)	Glutaraldehyde (U/mL)	Polyethyleneimine (PEI) (U/mL)	Sodium tripolyphosphate (U/mL)
Control	2.04 ± 0.04^a	2.68 ± 0.09^a	2.61 ± 0.07^a
0.1	0.18 ± 0.06^b	3.01 ± 0.04^b	1.68 ± 0.09^b
0.5	0.13 ± 0.01^b	2.25 ± 0.24^c	1.47 ± 0.10^c
1.0	0.12 ± 0.00^b	0.96 ± 0.07^d	1.43 ± 0.09^c
1.5	0.12 ± 0.02^b	0.81 ± 0.08^d	0.88 ± 0.10^d
2.0	0.11 ± 0.02^b	0.58 ± 0.06^d	0.55 ± 0.04^e
5.0	0.01 ± 0.01^c	0.74 ± 0.14^d	0.48 ± 0.09^e
10.0	0.00 ± 0.00^c	0.59 ± 0.27^d	0.34 ± 0.00^e

Obs. different letters indicate that they are statistically different (P < 0.05). Papain concentration was 10 g⋅L⁻¹ (1%—w⋅v⁻¹).