Affiliation:
1. University of Nigeria, Department of Microbiology, Industrial Microbiology and Biotechnology Laboratory, Nsukka, Nigeria
Abstract
Production of linamarase and the effects of media composition on enzyme
production were studied. A total of eight linamarase-producing bacteria were
isolated from fermenting cassava tubers and soil samples. Selection of the
isolates was based on their high growth in media containing 800 mg/L
potassium cyanide solution. Eight of the isolates which showed very high
growth in the growth medium as demonstrated by increase in their optical
density readings to at least 0.6 in the cyanide containing media were
selected for further studies. The isolates were identified as Lactobacillus
plantarum, Lactobacillus fermentum, Lactobacillus amylovorus, Lactobacillus
cellobiosus, Leuconostoc mesenteroides, Pseudomonas stutzeri, Bacillus
pumilus and Bacillus subtilis. All the isolates were grown in media
containing Tween 80 solution and in control media without the surfactant.
Best enzyme activity of 6.82 U/mL was obtained in the medium containing Tween
80 solution and Lactobacillus fermentum as the test bacterium. Comparatively,
linamarase production by the isolates in media without Tween 80 showed lower
enzyme productivity. Cassava endogenous and microbial enzymes were tested for
their abilities to hydrolyze cyanide in cassava flour samples pretreated to
either remove the endogenous or microbial enzyme. Residual cyanide in cassava
flour samples treated with linamarase of Lactobacillus plantarum was
undecteded in 30 h, while in contrast, the residual cyanide in cassava flour
samples treated with endogenous linamarase was 0.39 mg/10g cassava flour
after 80 h. Residual cyanide in the untreated control sample was 1.98 mg HCN
/10g cassava flour after 80 h. The results from this finding demonstrated
improved cassava cyanide degradation with microbial linamarase as compared to
endogenous cassava linamarase. Massive inoculation of fermenting cassava
tubers with the isolates reported in this study would enable better control
of the cassava fermentation process and may lead to the production of
standardized and non-toxic cassava food products.
Publisher
National Library of Serbia
Subject
General Chemical Engineering,General Chemistry
Cited by
5 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献