Studies on Production and Kinetic Properties of α-amylase from Rhizopus sp.This is some sample text.

1*Oparaji, Emeka, H., 3Chukwudozie, Izuchukwu, C.,  3Arazu, Amarachukwu, V., 2Oyibo, Okpanachi, N., 2Nworie Martin, B., 2Eze, Sabinus, O. and 2Chilaka, C. Ferdinand.This is some sample text.

Page No. 78-95

α-amylase producing Rhizopus was isolated from soil collected from Zoological Garden, University of Nigeria Nsukka, Enugu state. Biochemical test and microscopy mounting was used to confirm the strain as Rhizopus. The α-amylase producing ability of Rhizopus was determined using p-NPG as standard substrates. Rhizopus showed positive colouration on the substrates yellow colouration after two days of incubation. Optimization of the physiologic conditions for α-amylase production from Rhizopus was carried out in solid state fermentation system. α-amylase production peaked at pH 6.0.  Studies on the effect of incubation time on α-amylase production showed that the highest α-amylase production was obtained on the 5th day of fermentation. Crude proteins were precipitated using 80% saturation of ammonium sulphate salt with specific activity of 171.52 U/mg. Specific activity of 244.1 U/mg was obtained after gel filtration chromatography. α-amylase was purified upto 1.54 folds after the gel filtration with percentage yield of 2.4 %. The specific activity of the enzyme increased from 160.2 to 244.1 U/mg after gel filtration. Characterization of α-amylase gave optima pH and temperature of 5.0 and 60°C respectively. Km and Vmax of 4.5 mg/ml and 250 μmol/min were obtained respectively at various starch concentrations.  Ca2+ and Co2+enhanced α-amylase activity in the presence of Mn and Fe.
Keywords: α-amylase, Rhizopus, p-NPG, optimization, solid state fermentation.