Influence of the toxic compounds present in brewer's spent grain hemicellulosic hydrolysate on xylose-to-xylitol bioconversion by Candida guilliermondii
Influence of the toxic compounds present in brewer's spent grain hemicellulosic hydrolysate on xylose-to-xylitol bioconversion by Candida guilliermondii
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DOI：
10.1016/j.procbio.2005.06.024
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发表时间：
2005-12-01
影响因子：
4.4
通讯作者：
Roberto, IC
中科院分区：
文献类型：
--
作者：
Mussatto, SI;Dragone, G;Roberto, IC
以啤酒糟半纤维素水解液为原料，制备了含有不同浓度有毒物质的发酵培养基，并将其用于季氏假丝酵母（Candida guilliennondii）木糖转化为木糖醇的研究。这样的发酵培养基由水解产物以以下方式组成：原始（RH）;浓缩四倍（CH）;浓缩并用活性炭处理（TCH）;原料补充糖直到浓度高四倍（SRH）;浓缩并随后稀释但补充糖直到浓度高四倍（SDCH）。所有培养基的初始木糖浓度均为85 g/l，RH除外，其含有23 g/l木糖。发酵结果表明，在粗水解液中添加糖有利于木糖醇的产生。然而，由于培养基中存在高浓度的有毒化合物，CH的木糖醇生产受到负面影响。用活性炭处理水解物部分去除了有毒化合物，木糖醇产量高于CH，但不如SRH有效。因此得出结论，为了从BSG水解产物获得有效的木糖至木糖醇的生物转化，必须增加糖浓度，但必须将有毒化合物浓度降低至与粗水解产物中存在的相同水平。(c)2005 Elsevier Ltd.保留所有权利。
Fermentation media containing different concentrations of toxic compounds were prepared from brewer's spent grain (BSG) hemicellulosic hydrolysate, and used for xylose-to-xylitol bioconversion by Candida guilliennondii. Such fermentation media were composed of the hydrolysate in the following ways: raw (RH); concentrated four-fold (CH);. concentrated and treated with activated charcoal (TCH); raw supplemented with sugars until a concentration four-fold higher (SRH); concentrated and subsequently diluted but supplemented with sugars until a concentration four-fold higher (SDCH). All media presented an initial xylose concentration of 85 g/l, except RH, which contained 23 g/ I xylose. Fermentation results revealed that the sugars supplementation to raw hydrolysate favored the xylitol production. Nevertheless, xylitol production from CH was negatively affected due to the high concentration of toxic compounds present in the mediurn. The hydrolysate treatment with activated charcoal partially removed the toxic compounds, and the xylitol production was higher than in CH, but not so efficient as in SRH. It was thus concluded that to obtain an efficient xylose-to-xylitol bioconversion from BSG hydrolysate, the sugars concentration must be increased, but the toxic compounds concentration must be reduced to the same level present in the raw hydrolysate. (c) 2005 Elsevier Ltd. All rights reserved.