CAJ | 학술논문

[目的]研究酸性α-淀粉酶高产菌株B-5的发酵特性并对B-5菌株进行细菌鉴定,为进一步挖掘该菌株的应用价值奠定基础.[方法] 以B-5菌株为研究对象,通过菌体形态、菌落特征、生理生化特性以及16S rDNA同源性分析对其进行菌种鉴定.以单因素法和正交试验法对培养基进行优化,确定B-5菌株的最适发酵条件.[结果]通过传统细菌鉴定方法和分子生物学方法将B-5菌株初步鉴定为芽孢杆菌(Bacillus sp.).以可溶性淀粉、玉米粉、小麦粉作为碳源时,都有利于B-5菌株产酶,从工业化生产降低成本的角度考虑,选用玉米粉作为发酵产酶的碳源.而以胰蛋白胨作为氮源时产酶活力最高,故选用胰蛋白胨作为发酵产酶的氮源.正交试验结果表明,2%玉米粉和2%胰蛋白胨的培养基组成最有利于发酵产酶,酶活为74.6 U/ml.B-5菌株在60 h时,发酵液中酶活力达到最高,随着时间的延长,酶活力逐渐降低.[结论] B-5菌株虽然产酶活力还有限,尚不能满足工业化生产的需要,但该菌株的酸性α-淀粉酶性质优异,通过对其菌种的鉴定则可以方便地获取该酸性α-淀粉酶的基因以尝试酸性α-淀粉酶的工程菌生产.
[목적]연구산성α-정분매고산균주B-5적발효특성병대B-5균주진행세균감정,위진일보알굴해균주적응용개치전정기출.[방법] 이B-5균주위연구대상,통과균체형태、균락특정、생리생화특성이급16S rDNA동원성분석대기진행균충감정.이단인소법화정교시험법대배양기진행우화,학정B-5균주적최괄발효조건.[결과]통과전통세균감정방법화분자생물학방법장B-5균주초보감정위아포간균(Bacillus sp.).이가용성정분、옥미분、소맥분작위탄원시,도유리우B-5균주산매,종공업화생산강저성본적각도고필,선용옥미분작위발효산매적탄원.이이이단백동작위담원시산매활력최고,고선용이단백동작위발효산매적담원.정교시험결과표명,2%옥미분화2%이단백동적배양기조성최유리우발효산매,매활위74.6 U/ml.B-5균주재60 h시,발효액중매활력체도최고,수착시간적연장,매활력축점강저.[결론] B-5균주수연산매활력환유한,상불능만족공업화생산적수요,단해균주적산성α-정분매성질우이,통과대기균충적감정칙가이방편지획취해산성α-정분매적기인이상시산성α-정분매적공정균생산.
[Objective] The basis of the value of an acidic bacteria strain-B-5 of α-amylase-producing was further laid through the study on its high-yielding fermentation characteristics and its identification. [Method] The strain-B-5 being taken as the research object, its identification was done through the morphology, colony characteristics, physiological and biochemical characteristics and the analysis of 16S rDNA homology. The best fermentation condition of the strain was determined based on the optimum culture medium through the method of single-factor method and orthogonal test. [Results] The bacteria strain was identification as bacillus(Bacillus sp.) with the traditional method and molecular biological method. With soluble starch, corn flour or wheat flour as a carbon source, the strain-B-5 contributed to enzyme-producing. From the viewpoint of the cost reduction in industrial production, the corn flour could be adopted as a carbon source in its fermentation. And the tryptone was selected as nitrogen source because the highest activity of enzyme in its fermentation was produced by the nitrogen source. The orthogonal experiment results showed that it was most conducive to fermentation when the component of corn flour and tryptone in medium was 2%, respectively, with the activity of enzyme of 74.6 U/ml. The highest activity of enzyme in the B-5 fermentation appeared at the treatment time of 60th hour and the activity of enzyme was gradually decreased with time-lasting. [Conclusion] The activity of the enzyme of strain-B-5 was still limited, which yet could not meet the needs of industrial production, although nature of the acidic α-amylase produced by the strain was excellent. It was beneficial to the production of the bacteria strain of acidic α-amylase-producing for its industrialization through the identification of the gene in the strain.