Valentino Francesco, Morgan-Sagastume Fernando, Campanari Sabrina, Villano Marianna, Werker Alan, Majone Mauro
Department of Chemistry, Sapienza University of Rome, p.le Aldo Moro 5, 00185 Rome, Italy.
Veolia Water Technologies AB (AnoxKaldnes), Klosterängsvägen 11A, 22647, Lund, Sweden.
N Biotechnol. 2017 Jul 25;37(Pt A):9-23. doi: 10.1016/j.nbt.2016.05.007. Epub 2016 Jun 8.
Polyhydroxyalkanoates (PHA) are biodegradable polyesters that can be produced in bioprocesses from renewable resources in contrast to fossil-based bio-recalcitrant polymers. Research efforts have been directed towards establishing technical feasibility in the use of mixed microbial cultures (MMC) for PHA production using residuals as feedstock, mainly consisting of industrial process effluent waters and wastewaters. In this context, PHA production can be integrated with waste and wastewater biological treatment, with concurrent benefits of resource recovery and sludge minimization. Over the past 15 years, much of the research on MMC PHA production has been performed at laboratory scale in three process elements as follows: (1) acidogenic fermentation to obtain a volatile fatty acid (VFA)-rich stream, (2) a dedicated biomass production yielding MMCs enriched with PHA-storing potential, and (3) a PHA accumulation step where (1) and (2) outputs are combined in a final biopolymer production bioprocess. This paper reviews the recent developments on MMC PHA production from synthetic and real wastewaters. The goals of the critical review are: a) to highlight the progress of the three-steps in MMC PHA production, and as well to recommend room for improvements, and b) to explore the ideas and developments of integration of PHA production within existing infrastructure of municipal and industrial wastewaters treatment. There has been much technical advancement of ideas and results in the MMC PHA rich biomass production. However, clear demonstration of production and recovery of the polymers within a context of product quality over an extended period of time, within an up-scalable commercially viable context of regional material supply, and with well-defined quality demands for specific intent of material use, is a hill that still needs to be climbed in order to truly spur on innovations for this field of research and development.
聚羟基脂肪酸酯（PHA）是可生物降解的聚酯，与基于化石的生物难降解聚合物不同，它可以通过生物过程利用可再生资源生产。研究工作一直致力于确定使用混合微生物培养物（MMC）以残余物为原料生产PHA的技术可行性，这些残余物主要包括工业生产废水和污水。在这种情况下，PHA的生产可以与废物和废水的生物处理相结合，同时实现资源回收和污泥减量化。在过去的15年中，关于MMC生产PHA的研究大多在实验室规模下在以下三个工艺环节进行：（1）产酸发酵以获得富含挥发性脂肪酸（VFA）的物流；（2）专门的生物质生产，产生富含PHA储存潜力的MMC；（3）PHA积累步骤，其中将（1）和（2）的产出物在最终的生物聚合物生产生物过程中合并。本文综述了从合成废水和实际废水中生产MMC PHA的最新进展。本次批判性综述的目标是：a）突出MMC生产PHA三个步骤的进展，并提出改进空间；b）探索在市政和工业废水处理现有基础设施中整合PHA生产的思路和进展。在MMC生产富含PHA的生物质方面，已有许多技术进步和成果。然而，要在产品质量方面、在区域材料供应的可扩大规模的商业可行背景下、以及在针对特定材料用途的明确质量要求下，清晰展示聚合物的生产和回收，仍是该研发领域真正推动创新之前仍需跨越的一座山峰。
