Su Haijia, Liu Luo, Wang Shaojie, Wang Qingfeng, Jiang Yixin, Hou Xiaocong, Tan Tianwei
Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, No.15, Beisanhuan East Road, Beijing, 100029 People's Republic of China.
Biotechnol Biofuels. 2015 Feb 5;8:13. doi: 10.1186/s13068-015-0197-z. eCollection 2015.
As an efficient disposal method of food waste, anaerobic digestion (AD) for biogas production is widely used. In order to understand the enhanced efficiency and stability of AD by appropriate amounts of ammonia and volatile fatty acids (NH4 (+)/VFAs), the characteristics of the corresponding microbial community with ammonium acetate supplement were investigated by denatured gradient gel electrophoresis (DGGE) and pyrosequencing analyses of samples, with or without supplement of NH4 (+)/VFAs.
In this study, four different supplement strategies of adding ammonium acetate were investigated, including a blank group (without supplement of ammonium acetate), a low group (L group, 0.7 g/L/d), a moderate group (M group, 1.0 g/L/d) and a high group (H group, 1.3 g/L/d), respectively. The average daily gas production was 1,839 mL/d, 1,655 mL/d, 1,448 mL/d and 1,488 mL/d for L, M, H and blank groups, respectively. The results reveal that the absence or overload of NH4 (+)/VFAs leads to the inhibition or failure of the AD operation. The blank and H groups were selected for further investigation of the microbial community by DGGE and pyrosequencing analyses. A significant difference of the microbial communities at different AD stages was observed between the blank and H groups.
Ammonium acetate, as an efficient supplement, significantly influences the characteristics of a semi-continuous AD operation. The DGGE and pyrosequencing analyses indicated that the different bacterial and archaeal communities occurred in the blank and H groups at different AD stages. Thus, an appropriate ammonium acetate supplement may maintain the balance of the microbial community and could be applied to adjust the AD operation and microbial composition towards optimal biogas production.
作为一种高效的食物垃圾处理方法，厌氧消化（AD）用于沼气生产已被广泛应用。为了解适量的氨和挥发性脂肪酸（NH4(+)/VFAs）对厌氧消化效率和稳定性的提升作用，通过变性梯度凝胶电泳（DGGE）和焦磷酸测序分析，研究了添加醋酸铵前后样本中相应微生物群落的特征。
本研究考察了四种不同的醋酸铵添加策略，分别为空白组（不添加醋酸铵）、低剂量组（L组，0.7 g/L/d）、中剂量组（M组，1.0 g/L/d）和高剂量组（H组，1.3 g/L/d）。L组、M组、H组和空白组的日均产气量分别为1839 mL/d、1655 mL/d、1448 mL/d和1488 mL/d。结果表明，NH4(+)/VFAs的缺失或过量会导致厌氧消化运行受到抑制或失败。选择空白组和H组通过DGGE和焦磷酸测序分析进一步研究微生物群落。空白组和H组在不同厌氧消化阶段的微生物群落存在显著差异。
醋酸铵作为一种有效的添加物，对半连续厌氧消化运行的特征有显著影响。DGGE和焦磷酸测序分析表明，空白组和H组在不同厌氧消化阶段存在不同的细菌和古菌群落。因此，适当添加醋酸铵可以维持微生物群落的平衡，并可用于调整厌氧消化运行和微生物组成，以实现最佳沼气生产。
