Crude glycerol from biodiesel manufacture can be used as carbon source for microbial fermentations. The production of polyhydroxyalkanoates by manipulating the Sequencing Batch Reactor (SBR) selection stage of microbial mixed cultures (MMC) using high organic loading rates (OLR, 50CmM/day) and different cycles lengths (6, 12 and 24h) were optimized. Batch-production of polyhydroxybutyrate (PHB) presented an accumulation capacity in the high range (0.44g/g) after 3 pulses of 50CmM, with a final content of 59% PHB/wt., for the culture selected with 50CmM/day and a 24h cycle length. These values were in the range to those obtained with pure cultures and higher than the ones for MMC. With this strategy three main advantages in terms of the PHA production can be considered: utilization of a real waste without the resort to pure microbial cultures and a pre-fermentation step, consolidating the role of MMC in the valorisation of complex wastes/by-products.

中文翻译：

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从粗甘油生产聚羟基链烷酸酯的微生物选择策略：OLR 和循环长度的影响

来自生物柴油制造的粗甘油可用作微生物发酵的碳源。通过使用高有机负载率（OLR，50CmM/天）和不同的循环长度（6、12 和 24 小时）操纵微生物混合培养物 (MMC) 的序列分批反应器 (SBR) 选择阶段，对聚羟基链烷酸酯的生产进行了优化。聚羟基丁酸 (PHB) 的批量生产在 3 次 50CmM 脉冲后呈现出高范围 (0.44g/g) 的积累能力，最终含量为 59% PHB/wt。 24 小时循环长度。这些值在纯培养物获得的范围内，并且高于 MMC 的值。通过这种策略，可以考虑在 PHA 生产方面的三个主要优势：