Production of a-amylase in Bacillus sp. by solid state fermentation (SSF) technique using Musa textilis (banana) husk

Recently, the usage of enzymes in biotechnology become to take importance.One of these enzymes a-amylase is among the important biotechnological enzymes. a-Amylases are used at industry such as food, detergent, textil, paper and beer for hidrolisis of starch. The ratio of a-amylase activity was tested at different SSF sources such as banana, water melon and melon husk, wheat and lentil bran and maize used as subtrates by Bacillus sp. which is isolated from soil. The enzyme production from highest to the least is found as follows; banana husk > water melon husk > lentil bran > wheat bran > melon husk >maize. As the highest activity was seen with the banana husk, it was used as substrat in later studies. By SSF process, Bacillus sp. using banana husk as substrat a-amylase activity has been determined at different incubation time. The appropriate incubation time has been found 72. hours. By SSF process, Bacillus sp. using banana husk as substrat the effect of the addition of % 2 carbon sources on the a-amylase activity has been examined. The highest activity has been found at starch and the lowest one at glucose. Sucrose didn't effect the a-amylase activity. Glucose, mannose, galactose and arabinose were found to be lower than the control. By SSF process, Bacillus sp. using banana husk as substrat the effect of the addition of % 10 nitrogen sources on the a-amylase activity has been examined. Amonium sulfate, bacto casamino acid, bacto liver and methionin are found higher than the control. NH4CI and NH4N03 are found to be lower than the control. There was not seen any enzyme activity at urea. The highest enzyme activity has been observed at amonium sulfate. Some properties of a-amylase were examined on the supernatant of Bacillus sp. grow on NB medium. The a-amylase activity was tested between pH 4 -1 1. Optimum pH was found to be 6. The a-amylase activity was tested between 25 °C to 95 °C. Optimum temperature was found to be 60 °C. a- Amylase activity was carried out for determination of enzyme stability measurements over a period of time ( 30-240 minutes ) at 60 °C. The enzyme activity was increased between 15-90 minutes. Then between the minutes 90 and 240 a decrease in the enzyme activity was observed. However there was no change in enzyme activity after 240 minutes. The effects of 0.2 % detergents (SDS, CHAPS and Omo Matik) on enzyme activity over a period of time ( 15-90 minutes ) were tested and the order of inhibition effect from most to least was found as SDS > Omo Matik > CHAPS.