Purification and Partial Characterization of Major Viscous Protein from Yam (Dioscorea opposita Thunb.) Tuber Mucilage tororo

Figures & data

Figure 1 Purification of viscous protein from yam (Dioscorea opposita Thunb.) tuber mucilage tororo. (A) Phenyl-Toyopearl 650M column chromatography. (B) DEAE-Toyopearl 650M column chromatography of the Phenyl-Toyopearl 650M fraction. (C) CM-Toyopearl 650M column chromatography of the DEAE-Toyopearl 650M fraction.

Table 1 Purification of viscous protein from yam tuber mucilage tororo.

Fraction	Volume (mL)	Total protein (mg)	Kinematic viscosity (cSt)	Specific kinematic viscosity (cSt/mg protein)	Yield (%)	Purification (fold)
Crude extract	160.0	302.4	15.3	0.05	100	1
Phenyl -Toyopearl 650M	21.0	103.1	3.1	0.03	20.3	0.6
DEAE-Toyopearl 650M	15.2	17.8	1.9	0.11	12.4	2.1
CM-Toyopearl 650M	11.6	10.4	1.9	0.18	12.4	3.6

Figure 2 Nondenaturating polyacrylamide gel electrophoresis of the purified viscous protein from yam (D. opposita Thunb.) tuber mucilage tororo. (A) Molecular weight markers; (B) Purified viscous protein.

Figure 3 Estimation of molecular weight of the purified viscous protein from yam (D. opposita Thunb.) tuber mucilage tororo by gel filtration on Toyopearl HW-55F column (1.5 × 70 cm). The column was eluted with 10 mM sodium phosphate buffer (pH 6.0). The standard proteins used were as indicated.

Figure 4 SDS-polyacrylamide gel electrophoresis of molecular weight markers and purified viscous protein from yam (D. opposita Thunb.) tuber mucilage tororo. (A) Low molecular weight markers; (B) purified protein without reducing reagent; (C) purified protein with reducing reagent; (D) High molecular weight markers.

Figure 5 Carbonic anhydrase activity staining of crude extracts, DEAE-Toyopearl 650M fraction, and the purified viscous protein from yam (D. opposita Thunb.) tuber mucilage tororo. (A) crude extracts without reducing reagent; (B) crude extracts with reducing reagent; (C) DEAE-Toyopearl 650M fraction without reducing reagent; (D) DEAE-Toyopearl 650M fraction with reducing reagent; (E) purified protein without reducing reagent; (F) purified protein with reducing reagent.

Figure 6 Inhibition experiments of carbonic anhydrase activity of the purified protein from yam (D. opposita Thunb.) tuber mucilage tororo. (A) without inhibitor; (B) with inhibitor.

Figure 7 Effects of pH and temperature on the purified viscous protein from yam (D. opposita Thunb.) tuber mucilage tororo. (A) optimum pH; (B) pH stability; (C) optimum temperature; (D) thermal stability.