摘要
[目的] 对从陕北花马盐湖嗜盐真菌中筛选出的1株产纤维素酶菌株进行鉴定,研究该菌株的产酶条件,为嗜盐纤维素酶资源的利用提供理论依据。[方法] 利用刚果红培养基从陕北花马盐湖嗜盐真菌中筛选产纤维素酶菌株,并对其进行形态学和ITS序列鉴定,在单因素试验基础上,采用L9(34)正交试验,优化该产酶菌株的最佳培养基配方和最佳发酵条件,并研究该产酶菌株的NaCl耐受性。[结果] 从陕北花马盐湖嗜盐真菌中筛选出1株高产纤维素酶菌株6MA1,根据形态学和ITS序列系统发育分析,将该菌鉴定为黑曲霉(Aspergillus niger)。菌株产纤维素酶的最佳培养基配方是,玉米芯粉22.0g/L,蛋白胨6.0g/L,NaCl 4.0g/L,MgSO4·7H2O 0.55g/L,K2HPO40.5g/L;最佳发酵条件是,发酵温度28℃,发酵时间6d,起始pH 6.0,种子液接种量18%(体积分数),在此条件下菌株6MA1的CMCase活力为47.8U/mL。此外,该菌株在含0~15.0%(体积分数)NaCl的培养基中仍具有产纤维素酶活力。[结论] 从陕北花马盐湖筛选出1株产纤维素酶菌株6MA1,并得到了该菌株产酶的最佳条件。
[Objective] One cellulase-producing fungus screened from fungi in Huama Salt Lake in northern Shaanxi was identified and its fermentation conditions were tested to provide theoretical basis for the utilization of halophilic cellulase resources. [Method] First,Congo red medium was used to screen cel- lulase producing strain from halophilic fungi in Huama Salt Lake in northern Shaanxi and it was identified through morphology and ITS sequence. Then, the optimized medium and liquid-fermented conditions were obtained by L9 (34) orthogonal design. The NaC1 tolerance of obtained enzyme producing strain was studied as well. [Result] The cellulose-producing strain,6MAl,was isolated from halophilic fungi in Huama Salt Lake in northern Shaanxi. This isolate was classified as Aspergillus niger. The optimal medium contained the following components (g/L) : corncob powder 22.0, peptone 6.0, NaC1 4.0, MgSO4 · 7 H2 O 0.55, and KzHPO4 0. 5. The optimal liquid-fermented conditions were:initial medium pH 6.0,inoculum 18% ,at 28 ℃ for 6 days. Its CMCase activity reached 47.8 U/mL. In addtion, 6MA1 still produced cellulase when sub- mergerd in liquid media with 0-15.0G NaCl. [Conclusion] The study screened out a cellulase-produeing strain from Huama Salt Lake in northern Shaanxi and optimized its fermentation conditions.
出处
《西北农林科技大学学报(自然科学版)》
CSCD
北大核心
2016年第4期149-156,167,共9页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金青年基金项目(31100017)
陕西省青年科技新星科研计划项目(2013KJXX-76)
关键词
陕西花马盐湖
纤维素酶
嗜盐真菌
产酶条件
Huama Salt Lake in northern Shaanxi
cellulase
fungi
enzyme production conditions