Xylanase enzyme plays an important role in nature as being a part of protecting the environment from pollution. It has also various industrial applications. Marine fungal isolate was recovered from red sea water at Sharm El-Sheikh province, Egypt, and tested for xylanase activity, using different agricultural wastes as a substrate. It was found that rice straw was the best substrate for xylanase production (0.37 U/ml). Thus, it was subjected for identification by 18S rDNA gene. The phylogenetic analysis results indicated that this fungal isolate belonging to Aspergillus species with a similarity of 99% and named as A. oryzae SS_RS-SH (MN894021). The regular two-level factorial design was used to optimize the important medium components, which significantly affected the xylanase production. The model in equation suggested optimal conditions of 2% of rice straw, 8 g/l of yeast extract, 4 g/l of (NH4)2SO4, 2 g/l K2HPO4, and 2.5 g/l MgSO4.7H2O for a maximum xylanase yield. The antifungal activity of crude xylanase on mycelial growth of some pathogenic fungi isolated from different hosts was investigated. The results showed that xylanase T1 had a potent antifungal activity than control. Greenhouse experiments indicated that all treatments with xylanase at different concentrations significantly decreased infection occurrence of beans, which have been effectively infected with root rot pathogens, compared to unprocessed control treatments. Xylanase yield increased 2.43-folds than initial screening. The xylanase had a potential antifungal activity both in vitro and under greenhouse conditions. The outcome of this study ensured that this fungal strain could be used as biological control for plant disease.

中文翻译：

---

使用米曲霉MN894021的不同农业废料对木聚糖酶生产进行统计优化，作为蚕豆根病的生物防治

木聚糖酶作为保护环境不受污染的一部分，在自然界中起着重要作用。它还具有各种工业应用。在埃及沙姆沙伊赫省的红海水中回收了海洋真菌分离物，并使用不同的农业废料作为底物测试了木聚糖酶活性。发现稻草是生产木聚糖酶的最佳底物（0.37 U / ml）。因此，通过18S rDNA基因对其进行鉴定。系统发育分析结果表明，该真菌分离物属于曲霉菌种，具有99％的相似性，命名为米曲霉SS_RS-SH（MN894021）。常规的两级因子设计用于优化重要的培养基成分，从而显着影响木聚糖酶的产量。等式中的模型建议最佳条件为最大木聚糖酶的条件为2％稻草，8 g / l酵母提取物，4 g / l（NH4）2SO4、2 g / l K2HPO4和2.5 g / l MgSO4.7H2O让。研究了粗木聚糖酶对分离自不同宿主的某些致病真菌菌丝生长的抗真菌活性。结果表明，木聚糖酶T1具有比对照强的抗真菌活性。温室实验表明，与未处理的对照处理相比，用不同浓度的木聚糖酶进行的所有处理均显着减少了已被根腐病菌有效感染的豆类感染。木聚糖酶产率比初始筛选提高了2.43倍。木聚糖酶在体外和温室条件下均具有潜在的抗真菌活性。