Abstract：
The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH adjustment. The results showed that pH 8 was considered to be the most suitable condition for acid production, especially for the formation of acetic acid and propionic acid. The average value of total volatile fatty acid at pH 8 was 8814 mg COD/L, 1.5 times of that under blank condition. The average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L, respectively. The activities of key functional enzymes such as phosphotransacetylase, acetokinase, oxaloacetate transcarboxylase and succinyl-coA transferase were all enhanced. To further explore the regulatory mechanisms within the system, the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing, results indicating that the relative abundances of Clostridiales, Bacteroidales, Chloroflexi, Clostridium, Bacteroidetes and Propionibacteriales, which were great contributors for the hydrolysis and acidification, increased rapidly at pH 8 compared with the blank group. Besides, the proportion of genes encoding key enzymes was generally increased, which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.
摘要：
在pH值调节下，对预处理后的餐厨垃圾进行了厌氧产酸实验。结果表明,pH8被认为是最适宜的产酸条件,特别是形成乙酸和丙酸。总挥发性脂肪酸在pH8时的平均值为8814mgCOD/L,空白条件下的1.5倍。乙酸和丙酸的平均产率分别为3302mgCOD/L和2891mgCOD/L，分别。关键功能酶的活性，如磷酸转乙酰酶，乙酰激酶，草酰乙酸转羧化酶和琥珀酰辅酶A转移酶均增强。进一步探索体制内的调控机制,通过微生物测序获得不同水平微生物在发酵系统中的分布，结果表明，梭菌的相对丰度，拟杆菌,氯氟菌,梭菌属,拟杆菌和丙酸杆菌,它们是水解和酸化的重要贡献者，与空白组相比，在pH为8时迅速增加。此外,编码关键酶的基因比例普遍增加，进一步验证了pH调节下水解酸化和乙酸生产有机物的机理。
