Hussain Azhar A, Abdel-Salam Mohamed S, Abo-Ghalia Hoda H, Hegazy Wafaa K, Hafez Safa S
Botany Department, Faculty of Women for Arts, Science and Education, Ain Shams Univ., Egypt.
Microbial Genetics Department, National Research Centre, P.O. 12622, Dokki, Giza, Egypt.
J Genet Eng Biotechnol. 2017 Jun;15(1):77-85. doi: 10.1016/j.jgeb.2017.02.007. Epub 2017 Mar 14.
Cellulase producing bacteria were isolated from both soil and ward poultry, using CMC (carboxymethylcellulose) agar medium and screened by iodine method. Cellulase activity of the isolated bacteria was determined by DNS (dinitrosalicylic) acid method. The highly cellulolytic isolates (BTN7A, BTN7B, BMS4 and SA5) were identified on the basis of Gram staining, morphological cultural characteristics, and biochemical tests. They were also identified with 16S rDNA analysis. The phylogenetic analysis of their 16S rDNA sequence data showed that BTN7B has 99% similarity with , BMS4 has 99% similarity with , SA5 has 99% homology with and BTN7A was 99% similar with . Cellulase production by these strains was optimized by controlling different environmental and nutritional factors such as pH, temperature, incubation period, different volumes of media, aeration rate and carbon source. The cellulase specific activity was calculated in each case. In conclusion four highly cellulolytic bacterial strains were isolated and identified and the optimum conditions for each one for cellulase production were determined. These strains could be used for converting plant waste to more useful compounds.
利用羧甲基纤维素(CMC)琼脂培养基从土壤和家禽饲养场中分离出产纤维素酶的细菌,并采用碘法进行筛选。通过二硝基水杨酸(DNS)法测定分离出的细菌的纤维素酶活性。根据革兰氏染色、形态培养特征和生化试验对高度纤维素分解的分离株(BTN7A、BTN7B、BMS4和SA5)进行鉴定。还通过16S rDNA分析对它们进行了鉴定。对其16S rDNA序列数据的系统发育分析表明,BTN7B与……有99%的相似性,BMS4与……有99%的相似性,SA5与……有99%的同源性,BTN7A与……有99%的相似性。通过控制不同的环境和营养因素,如pH值、温度、培养时间、不同体积的培养基、通气速率和碳源,对这些菌株的纤维素酶生产进行了优化。计算了每种情况下纤维素酶的比活性。总之,分离并鉴定了四株高度纤维素分解的细菌菌株,并确定了每株菌株产生纤维素酶的最佳条件。这些菌株可用于将植物废料转化为更有用的化合物。