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论文类型：期刊论文

发表时间：2016-07-01

发表刊物：ELECTRONIC JOURNAL OF BIOTECHNOLOGY

收录刊物：SCIE、EI、Scopus

卷号：22

页面范围：1-8

ISSN号：0717-3458

关键字：Align; Bacillus amyloliquefaciens; Central-Composite Design; Plackett-Burman design; Sea cucumber

摘要：Background: The alga Laminaria japonica is the most economically important brown seaweed cultured in China, which is used as food and aquatic animal feedstuff. However, the use of L. japonica as a feedstuff in Apostichopus japonicas farming is not ideal because A. japonicas does not produce enough enzyme activity for degrading the large amount of algin present in L. japonica. In this study, semi solid fermentation of the L. japonica feedstuff employing a Bacillus strain as the microbe was used to as a mean to degrade the algin content in L. japonica feedstuff.
   Results: The Bacillus strain, Bacillus amyloliquefaciens WB1, was isolated by virtue of its ability to utilize sodium alginate as the sole carbon source. Eight factors affecting growth and algin-degrading capacity of WB1 were investigated. The results of Plackett-Burman design indicated that fermentation time, beef extract, and solvent to solid ratio were the significant parameters. Furthermore, the mutual interaction between the solvent to solid ratio and beef extract concentration was more significant than the other pairs of parameters on algin degradation. Optimal values obtained from Central-Composite Design were 113.94 h for fermentation time, 0.3% (w/v) beef extract and 44.87 (v/w) ratio of solvent to feedstuff. Under optimal conditions, 56.88% of the algin was degraded when a 50-fold scale-up fermentation was carried out, using a 5-L fermenter.
   Conclusions: This study provides an alternative and economical way to reduce the algin content in L. japonica through degradation by WB1, making it a promising potential source of feed for cultured L. japonica. (C) 2016 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. All rights reserved.