Kiranmayi M Usha, Poda Sudhakar, Vijayalakshmi M, Krishna P V
Department of Microbiology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, 522 510, India.
J Environ Biol. 2011 Nov;32(6):695-9.
The objective of this study was to determine the influence of natural biowaste substrates such as banana peel powder and coir powder at varying environmental parameters of pH (4-9) and temperature (20-50 degrees C) on the cellulase enzyme production by Aspergillus niger. The cellulase enzyme production was analyzed by measuring the amount of glucose liberated in IU ml(-1) by using the dinitrosalicylic acid assay method. The substrates were pretreated with 1% NaOH (alkaline treatment) and autoclaved. The maximum activity of the enzyme was assayed at varying pH with temperatures being constant and varying temperatures with pH being constant. The highest activity of the enzyme at varying pH was recorded at pH 6 for banana peel powder (0.068 +/- 0.002 IU ml) and coir powder (0.049 +/- 0.002 IU ml(-1)) and the maximum activity of the enzyme at varying temperature was recorded at 35 degrees C for both banana peel powder (0.072 +/- 0.001 IU ml(-1)) and coir powder (0.046 +/- 0.003 IU ml(-1)). At varying temperatures and pH the high level of enzyme production was obtained at 35 degrees C and pH 6 by using both the substrates, respectively. However among the two substrates used for the production of cellulases by Aspergillus niger banana peel powder showed maximum enzymatic activity than coir powder as substrate.
本研究的目的是确定天然生物废料底物（如香蕉皮粉和椰壳粉）在不同的pH值（4 - 9）和温度（20 - 50摄氏度）环境参数下对黑曲霉产生纤维素酶的影响。通过使用二硝基水杨酸测定法测量以国际单位每毫升（IU ml⁻¹）释放的葡萄糖量来分析纤维素酶的产生。底物用1%氢氧化钠进行预处理（碱性处理）并进行高压灭菌。在温度恒定且pH值变化以及pH值恒定且温度变化的情况下测定酶的最大活性。在不同pH值下，香蕉皮粉（0.068 ± 0.002 IU ml）和椰壳粉（0.049 ± 0.002 IU ml⁻¹）在pH 6时记录到酶的最高活性，在不同温度下，香蕉皮粉（0.072 ± 0.001 IU ml⁻¹）和椰壳粉（0.046 ± 0.003 IU ml⁻¹）在35摄氏度时记录到酶的最大活性。在不同温度和pH值下，分别使用两种底物在35摄氏度和pH 6时获得了高水平的酶产量。然而，在用于黑曲霉生产纤维素酶的两种底物中，香蕉皮粉作为底物时显示出比椰壳粉更高的酶活性。
