Tawfiki Hajji K, Lépine F, Bisaillon J G, Beaudet R
Centre de Microbiologie et de Biotechnologie, Institut National de la Recherche Scientifique- Institut Armand Frappier, Université du Quebec, Ville de Laval, Canada.
Can J Microbiol. 1999 Apr;45(4):318-25.
Two different anerobic consortia, one removing phenol and ortho (o-) cresol and other removing para(p-) cresol, were cultivated in serum bottles using whey as cosubstrate substitute for proteose peptone. Phenol and p-cresol removal with the phenol-removing consortium were the same with 0.0125% (w/v) whey as with 0.05% proteose peptone. For the other consortium, 8 days were required to decrease the p-cresol concentration from 35 to 2 mg/L with 0.025% whey, while 35 days were required to achieve a similar removal with 0.5% proteose peptone. The two consortia were mixed and cultivated with 0.025% whey. Phenolic compound removal with the mixed consortia was as good as that achieved by each of the two initial consortia against their respective substrates. This removal activity was maintained after several transfers. In a continuous upflow fixed-film reactor, the mixed consortia removed over 98% of 150 mg/L of phenol and 35 mg/L of each o- and p-cresol in the influent at 29 degrees C, with 0.025% whey as cosubstrate. The hydraulic retention time (HRT) was 0.25 day, corresponding to a phenolic compound volumic loading rate of 880 mg/(L of reactor x day). Once the continuous flow reactor achieved constant phenolic compound removal, no intermediates were found in the effluent, while in serum bottles, m-toluic acid, an o-cresol intermediate, accumulated. Measurements of the specific activity for the uptake of different substrates demonstrated the presence of all trophic groups involved in methanogenic fermentation. These activities were, in mg of substrate/(g of volatile suspended solids x day), as follows: 849 +/- 25 for the acidogens; 554 +/- 15 for the acetogens; 934 +/- 37 for the aceticlastic methanogens; and 135 +/- 15 for the hydrogenophilic methanogens. Electron micrographs of the mixed consortia showed seven different morphological bacterial types, including Methanotrix-like bacteria.
使用乳清作为蛋白胨的共底物替代物，在血清瓶中培养了两种不同的厌氧菌群，一种去除苯酚和邻甲酚，另一种去除对甲酚。去除苯酚的菌群去除苯酚和对甲酚时，0.0125%（w/v）的乳清与0.05%的蛋白胨效果相同。对于另一个菌群，用0.025%的乳清将对甲酚浓度从35mg/L降至2mg/L需要8天，而用0.5%的蛋白胨达到类似去除效果则需要35天。将这两个菌群混合并用0.025%的乳清培养。混合菌群对酚类化合物的去除效果与两个初始菌群各自对其相应底物的去除效果一样好。经过几次传代后，这种去除活性得以维持。在连续上流式固定膜反应器中，混合菌群在29℃下，以0.025%的乳清作为共底物，去除了进水150mg/L的苯酚以及35mg/L的邻甲酚和对甲酚，去除率超过98%。水力停留时间（HRT）为0.25天，对应酚类化合物的体积负荷率为880mg/（L反应器×天）。一旦连续流反应器实现了稳定的酚类化合物去除，在流出物中未发现中间产物，而在血清瓶中，邻甲酚的中间产物间甲苯酸积累了。对不同底物摄取的比活性测量表明存在参与产甲烷发酵的所有营养菌群。这些活性以mg底物/（g挥发性悬浮固体×天）计，如下：产酸菌为849±25；产乙酸菌为554±15；乙酸裂解产甲烷菌为934±37；嗜氢产甲烷菌为135±15。混合菌群的电子显微镜照片显示有七种不同形态的细菌类型，包括类甲烷鬃菌属细菌。
