In this study, a four-microorganism three-step fermentation process was established for producing medium-chain-length polyhydroxyalkanoate (mcl-PHA) from starch, which was used as the sole carbon source. The four microorganisms used for this process were Aspergillus niger, Saccharomyces cerevisiae L2612, Acetobacter orientalis, and Pseudomonas putida KT2440-acs. The initial carbon source starch concentration was set to 30 g/L, the maximum glucose concentration reached 17.66 g/L at 48 h after starch hydrolysis, and then, 2.36 g/L of acetic acid was obtained at 96 h. The final output of mcl-PHA was 0.5 g/L at 144 h, overall productivity for mcl-PHA was 3.47 mg/(L·h) and the total starch to mcl-PHA yield for the process was 16.67 mg/g. Although the overall yield and conversion rate of this process were not high, this is the first attempt to produce mcl-PHA using starch as a substrate, and it provides a feasible strategy for producing PHA from kitchen waste. The production process of mcl-PHA with a clear flora structure and short fermentation cycle was realized.

在这项研究中，建立了一种四微生物三步发酵工艺，用于以淀粉为唯一碳源生产中等链长的聚羟基链烷酸酯 (mcl-PHA)。用于该过程的四种微生物是黑曲霉、酿酒酵母L2612、东方醋杆菌和恶臭假单胞菌KT2440- acs. 初始碳源淀粉浓度设定为30 g/L，淀粉水解48 h后葡萄糖浓度最高达到17.66 g/L，96 h后得到2.36 g/L醋酸。在 144 小时时 mcl-PHA 的最终产量为 0.5 g/L，mcl-PHA 的总生产率为 3.47 mg/(L·h)，该过程中淀粉对 mcl-PHA 的总产量为 16.67 mg/g。虽然该工艺的整体收率和转化率不高，但这是首次尝试以淀粉为底物生产mcl-PHA，为利用餐厨垃圾生产PHA提供了可行的策略。实现了菌群结构清晰、发酵周期短的mcl-PHA生产工艺。