Asiri Fahad, Chen Chih-Hung, Hwangbo Myung, Shao Yiru, Chu Kung-Hui
Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, Texas 77843-3136, United States.
Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
ACS Omega. 2020 Sep 17;5(38):24158-24168. doi: 10.1021/acsomega.9b04002. eCollection 2020 Sep 29.
Poly(3-hydroxybutyrate) (PHB)-a renewable and biodegradable polymer-is a promising alternative to nonbiodegradable synthetic plastics that are derived from petrochemicals. The methods currently employed for PHB production are costly, in part, due to the expensive cultivation feedstocks and the need to sterilize the culture medium, which is energy-intensive. This study investigates the feasibility of nonsterile PHB production from several saline organic wastes using a salt-tolerant strain, ZD1 (referred to as strain ZD1). Factors such as the pH, salinity, carbon/nitrogen (C/N) ratio, nitrogen source, and electron acceptor that might affect the growth of strain ZD1 and its PHB production were determined. Our results showed successful nonsterile PHB production by growing the strain ZD1 on nonsterile synthetic crude glycerol, high-strength saline wastewater, and real municipal wastewater-activated sludge under saline conditions. The PHB production was significantly enhanced when the levels of salts and nitrate-nitrogen in the culture medium were increased. This study suggested a promising low-cost nonsterile PHB production strategy from organic wastes using strain ZD1.
聚（3-羟基丁酸酯）（PHB）——一种可再生且可生物降解的聚合物——是源自石化产品的不可生物降解合成塑料的一种有前景的替代品。目前用于生产PHB的方法成本高昂，部分原因在于昂贵的培养原料以及对培养基进行灭菌的需求，而这一过程能耗巨大。本研究使用耐盐菌株ZD1（简称菌株ZD1）探究了利用几种含盐有机废物进行非无菌生产PHB的可行性。确定了可能影响菌株ZD1生长及其PHB产量的因素，如pH值、盐度、碳氮（C/N）比、氮源和电子受体。我们的结果表明，在含盐条件下，通过使菌株ZD1在非无菌合成粗甘油、高强度含盐废水和实际城市污水活性污泥上生长，成功实现了非无菌生产PHB。当培养基中的盐和硝酸盐氮含量增加时，PHB产量显著提高。本研究提出了一种利用菌株ZD1从有机废物中生产低成本非无菌PHB的有前景的策略。
