Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak, 124001, Haryana, India.
J Ind Microbiol Biotechnol. 2013 Aug;40(8):891-9. doi: 10.1007/s10295-013-1277-3. Epub 2013 May 8.
Among three hundred isolates of filamentous fungi, Aspergillus oryzae SBS50 secreted higher phytase activity at pH 5.0, 35 °C and 200 rpm after 96 h of fermentation. Starch and beef extract supported the highest phytase production than other carbon and nitrogen sources. A nine-fold improvement in phytase production was achieved due to optimization. Supplementation of the medium with inorganic phosphate repressed the enzyme synthesis. Among surfactants tested, Tween 80 increased fungal growth and phytase production, which further resulted in 5.4-fold enhancement in phytase production. The phytase activity was not much affected by proteases treatment. The enzyme resulted in the efficient hydrolysis of insoluble phytate complexes (metal- and protein-phytates) in a time dependent manner. Furthermore, the hydrolysis of insoluble phytates was also supported by scanning electron microscopy. The enzyme, being resistant to trypsin and pepsin, and able to hydrolyze insoluble phytates, can find an application in the animal food/feed industry for improving nutritional quality and also in combating environmental phosphorus pollution and plant growth promotion.
在 300 株丝状真菌的分离株中，米曲霉 SBS50 在发酵 96 小时后，在 pH5.0、35°C 和 200rpm 的条件下分泌更高的植酸酶活性。淀粉和牛肉提取物比其他碳源和氮源支持更高的植酸酶产量。通过优化，植酸酶产量提高了九倍。培养基中添加无机磷酸盐会抑制酶的合成。在所测试的表面活性剂中，吐温 80 增加了真菌的生长和植酸酶的产生，从而使植酸酶的产量进一步提高了 5.4 倍。蛋白酶处理对植酸酶活性的影响不大。该酶能有效地水解不溶性植酸盐复合物（金属和蛋白质植酸盐），并具有时间依赖性。此外，扫描电子显微镜也支持不溶性植酸盐的水解。该酶能抵抗胰蛋白酶和胃蛋白酶，且能水解不溶性植酸盐，可在动物食品/饲料工业中用于改善营养质量，还可用于防治环境磷污染和促进植物生长。
