Correa-Galeote David, Argiz Lucia, Val Del Rio Angeles, Mosquera-Corral Anuska, Juarez-Jimenez Belen, Gonzalez-Lopez Jesus, Rodelas Belen
Microbiology Department, Faculty of Pharmacy, University of Granada, 18011 Granada, Spain.
Microbiology and Environmental Technology Section, Water Institute, University of Granada, 18011 Granada, Spain.
Polymers (Basel). 2022 Mar 29;14(7):1396. doi: 10.3390/polym14071396.
The biosynthesis of polyhydroxyalkanoates (PHAs) from industrial wastes by mixed microbial cultures (MMCs) enriched in PHA-accumulating bacteria is a promising technology to replace petroleum-based plastics. However, the populations' dynamics in the PHA-accumulating MMCs are not well known. Therefore, the main objective of this study was to address the shifts in the size and structure of the bacterial communities in two lab-scale sequencing batch reactors (SBRs) fed with fish-canning effluents and operated under non-saline (SBR-N, 0.5 g NaCl/L) or saline (SBR-S, 10 g NaCl/L) conditions, by using a combination of quantitative PCR and Illumina sequencing of bacterial 16S rRNA genes. A double growth limitation (DGL) strategy, in which nitrogen availability was limited and uncoupled to carbon addition, strongly modulated the relative abundances of the PHA-accumulating bacteria, leading to an increase in the accumulation of PHAs, independently of the saline conditions (average 9.04 wt% and 11.69 wt%, maximum yields 22.03 wt% and 26.33% SBR-N and SBR-S, respectively). On the other hand, no correlations were found among the PHAs accumulation yields and the absolute abundances of total , which decreased through time in the SBR-N and did not present statistical differences in the SBR-S. , , , , , , and were key PHA-accumulating genera in both SBRs under the DGL strategy, which was revealed as a successful tool to obtain a PHA-enriched MMC using fish-canning effluents.
通过富含聚羟基脂肪酸酯（PHA）积累细菌的混合微生物培养物（MMC）从工业废料中生物合成聚羟基脂肪酸酯是一种有望替代石油基塑料的技术。然而，PHA积累MMC中菌群的动态变化尚不清楚。因此，本研究的主要目的是通过结合定量PCR和细菌16S rRNA基因的Illumina测序，研究在两个实验室规模的序批式反应器（SBR）中，以鱼罐头废水为原料，在非盐（SBR-N，0.5 g NaCl/L）或盐（SBR-S，10 g NaCl/L）条件下运行时，细菌群落的大小和结构变化。一种双重生长限制（DGL）策略，即限制氮的可用性并使其与碳添加解耦，强烈调节了PHA积累细菌的相对丰度，导致PHA积累增加，且与盐条件无关（SBR-N平均为9.04 wt%和11.69 wt%，最大产量分别为22.03 wt%和26.33%；SBR-S）。另一方面，未发现PHA积累产量与总量的绝对丰度之间存在相关性，总量在SBR-N中随时间下降，在SBR-S中无统计学差异。在DGL策略下，在两个SBR中，[具体菌属名称未给出]是关键的PHA积累菌属，这表明DGL策略是利用鱼罐头废水获得富含PHA的MMC的成功工具。
