Production and Biochemical Characterization of a High Maltotetraose (G4) Producing Amylase from Pseudomonas stutzeri AS22
Figure 6
Thin-layer chromatography (a) and GPC (b) analysis of the soluble starch hydrolysates by crude α-amylases of P. stutzeri AS22. The reaction mixture containing 0.2 U of α-amylase activity and 1% substrate in 0.1 M Tris-HCl buffer (pH 8.0) was incubated at 60°C. (a) Lane 1: standard maltooligosaccharides (G1–G7), lane 2: starch used as substrate, and lanes 3–9: soluble starch hydrolyzed by P. stutzeri AS22 after 2 min, 10 min, 30 min, 1 h, 2 h, 4 h, and 6 h. (b) End products analysis after 6 h hydrolysis of soluble starch. GPC analysis was performed on a Bio-Gel P2 column (1.5 × 200 cm) eluted with water at a rate of 30 mL/h. The different oligosaccharides released after starch hydrolysis were fractionated and quantified in comparison with standard oligosaccharides ranging from G1 to G7. G1: glucose, G2: maltose, G3: maltotriose, G4: maltotetraose, G5: maltopentaose, G6: maltohexaose, and G7: maltoheptaose. V0: the void volume.
