Autolysis of rice bran phytate in long-term study on batch fermentor

Microorganisms especially bacteria produce a diverse of phytate-degrading enzymes. Rice bran is excellent media for bacterial growth and enzymes secretion. The aim of the study was autolysis of rice bran phytate (6%) in long-term on batch fermentor (with constant agitator speed (300 rpm) and fixed air flow rate (0.5kg/cm2). The phytase production in the fermentor was with gradual color change from initial light green to dense green during the fermentation processes. The pH and temperature changes during production of phytase in the rice bran media over 10 weeks were observed. Initial 3 weeks, a reduction in pH from pH 6 to pH 4.2. After the middle of 4thweek and 5thweek considerable increase in pH towards the neutral range was observed i.e. from pH 6.2 to pH 6.99. In the 5thand6thweeks the pH range was found to be pH 7 to pH 7.9. Starting from the beginning of 8thweek to 10thweek pH was in the near alkaline range pH 8-pH 8.2. The temperature of the media during the initial stages of fermentation for first 3 weeks was 22-25°C. Increase in temperature was noticed after the end of the third week. The remaining weeks from 3 to 10 the temperature range was 25°C-29°C. The temperature of the media inside the fermentor was in between 22°C and 29°C throughout the study (environment temperature 20-40°C). Enzymatic partitional hydrolyzed of rice bran phytate into lower myoinsitolphosophates will have many health benefits applications

Optimization of the conditions for rice bran phytate degradation by their own phytases

The rice bran by-product of rice during milling process chemically contains moisture, ash, crude protein (12%), crude fat (15%), crude fiber 7%, crude carbohydrate (31.1%), and energy. It contains high phytate and dietary fiber contents. The cereal whole paddy after milling produces 8% of rice bran. Rice bran amino acid profile has been normally suggested to be superior to cereal grain proteins. Existing phytase within the rice bran generally improves phytate phosphorus utilizations. The present study has been conducted to find the effect of phytase activity of rice bran against five different temperatures and also the effect of phytase activity of rice bran against five different temperatures at optimum pH 5.5. The results showed that as the concentration of rice bran increases from 0 to 20%, the phytase activity also increased. The optimum phytase activity was found at 10% concentration of rice bran at 37°C. Moreover, an increase in phytase activity at the same concentration of rice bran was observed while adjusting the pH at pH 5.5. The four concentrations of rice bran showed gradual increase in activity at 50°C which was directly proportional to the concentrations of rice bran and comparatively better while adjusting the pH at pH 5.5. Around two-fold increase in activity was observed at room temperature and 50°C when the concentration of rice bran was increased from 5 to 20% with and without pH 5.5 adjustments