Table 1.

Partitioning of elastase and cells from Bacillus sp. fermentation broth in PEG-salt ATPSs

Salts	Recovery of elastase (%)	Kelastase	Kcell	Purification factor
MgSO4·7H2O	43.6±3.0c	2.84	1.27	1.23±0.05
(NH4)2SO4	65.0±2.9b	6.88	1.90	1.22±0.09
K2HPO4	64.4±2.0b	9.34	0.51	0.74±0.03
KH2PO4-K2HPO4	77.9±2.4a	11.73	0.26	1.17±0.08

Each ATPS was composed of 20% (w/w) PEG 2000 and 13.2% (w/w) inorganic salt at pH 7.5; After elastase recovery, experiments were conducted to estimate the experimental error;

^astand for the significant difference between each treatment as revealed by Duncan’s multiple range test (P=0.05)

^bstand for the significant difference between each treatment as revealed by Duncan’s multiple range test (P=0.05)

^cstand for the significant difference between each treatment as revealed by Duncan’s multiple range test (P=0.05)