Faculty of Life and Social Sciences, Environment and Biotechnology Centre, Swinburne University of Technology, Hawthorn 3122, Australia.
World J Microbiol Biotechnol. 2013 Feb;29(2):335-45. doi: 10.1007/s11274-012-1187-y. Epub 2012 Oct 10.
Endophytes are microorganisms that live within plant tissues that are potential sources of novel bioactive compounds, including enzymes. We have identified endophytes of the Australian native plant Eremophilia longifolia which were screened for the production of industrially useful enzymes. Seventeen fungal endophytes were isolated from the leaves of E. longifolia and enzyme production was investigated within a range of pH (3.5, 5.5, 7 and 9) and temperatures (9, 25, 37 and 50 °C). Amylase was the most common enzyme encountered with numerous isolates showing production throughout the temperature and pH ranges. Protease production was also seen over the conditions tested but was more dominant at lower pH and temperature. Activity was not observed for other enzymes including ligninase, xylanase and cellobiohydrolase. Enzymes from isolates of Preussia minima, Alternaria sp. and an unclassified fungus, which showed highest activity in screening assays, were investigated further. Enzyme production was verified by zymography and the amylase activity of P. minima was found to be significantly greater than that of Aspergillus oryzae particularly in alkaline conditions and low temperature which are desirable properties for the detergent industry. This work shows that enzymes with potential use in industry can be readily identified in fungal endophytes.
内生菌是生活在植物组织内的微生物，它们是新型生物活性化合物（包括酶）的潜在来源。我们已经鉴定出澳大利亚本土植物长叶埃默洛菲亚（Eremophilia longifolia）的内生菌，这些内生菌被筛选用于生产工业上有用的酶。从长叶埃默洛菲亚的叶子中分离出了 17 种真菌内生菌，并在一系列 pH 值（3.5、5.5、7 和 9）和温度（9、25、37 和 50°C）下研究了酶的生产。淀粉酶是最常见的酶，许多分离株在整个温度和 pH 范围内都有生产。在测试条件下也观察到了蛋白酶的产生，但在较低的 pH 值和温度下更为占主导地位。其他酶如木质素酶、木聚糖酶和纤维二糖水解酶则没有活性。在筛选试验中表现出最高活性的 Preussia minima、Alternaria sp. 和一种未分类的真菌的分离株的酶进一步进行了研究。通过同工酶电泳验证了酶的生产，发现 Preussia minima 的淀粉酶活性明显大于米曲霉（Aspergillus oryzae），特别是在碱性条件和低温下，这是洗涤剂工业所需要的特性。这项工作表明，内生真菌中很容易鉴定出具有工业应用潜力的酶。
