Department of Environmental Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-ku, Kyoto 615-8540, Japan.
Bioresour Technol. 2011 Nov;102(21):9933-41. doi: 10.1016/j.biortech.2011.08.060. Epub 2011 Aug 24.
The objective of this study was to evaluate the promotion effect of ammonia on the biodegradation of polylactide (PLA) under hyperthermophilic (80°C) and thermophilic (55°C) anaerobic condition. The results showed that PLA was transformed to lactic acid under hyperthermophilic conditions, but that the transformation ratio was negligible under thermophilic conditions. The hydrolysis process can be markedly increased with ammonia addition and microorganism activity. The maximum transformation ratios of the two kinds of PLA used in this study were 65.2% and 51.8%, respectively, with ammonia addition of 4 g N/L over 3 days treatment of anaerobic sludge. After the hyperthermophilic pretreatment, the hydrolysis products were converted to methane by methanogens under the thermophilic and anaerobic conditions. The final methane conversion ratios of the two kinds of PLA after 22 days treatment were 81.8% and 77.0%, respectively.
本研究旨在评估氨在高温（80°C）和嗜热（55°C）厌氧条件下对聚乳酸（PLA）生物降解的促进作用。结果表明，PLA 在高温条件下转化为乳酸，但在嗜热条件下转化率可忽略不计。添加氨和提高微生物活性可显著促进水解过程。两种 PLA 的最大转化率分别为 65.2%和 51.8%，在 3 天的厌氧污泥处理中添加 4 g N/L 的氨。高温预处理后，水解产物在嗜热和厌氧条件下由产甲烷菌转化为甲烷。两种 PLA 经 22 天处理后的最终甲烷转化率分别为 81.8%和 77.0%。
