CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China.
CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
Sci Total Environ. 2022 Jul 15;830:154783. doi: 10.1016/j.scitotenv.2022.154783. Epub 2022 Mar 24.
In this study, microbes were added to food waste compost in order to investigate the bioaugmentation mechanism of Humic acid (HA) formation. Thermogravimetric analysis, structural equation model, Fourier transform infrared spectroscopy and statistical analysis were utilized to explain the bioaugmentation mechanism. The results showed that bioaugmentation increased humification rate and degree. Bioaugmentation not only promoted the formation of aromatic structures and CC bonds but also brought different change orders of functional groups in HA. The HA obtained in bioaugmentation group (BA, 7.51 g/kg) was significantly higher compared to the control group (CK, 2.37 g/kg). Similarly, the HA/FA of BA (1.90) was also higher than that of CK (0.62), and peaked at 2.34 on day 40. The polyphenol humification pathway played a major role regardless of the addition of inoculant. However, the exogenous microbes promoted protein and carbohydrate degradation in the initial stage, and the abundance of precursors (amino acids and reducing sugars) enhanced both Maillard and polyphenol humification pathways. When polyphenol was insufficient in later stage, bioaugmentation mainly embodied in the strengthening of Maillard humification pathway. This finding benefited the practice of directional humification process of food waste composting.
在本研究中，向食物垃圾堆肥中添加微生物，以研究腐殖酸（HA）形成的生物增强机制。采用热重分析、结构方程模型、傅里叶变换红外光谱和统计分析来解释生物增强机制。结果表明，生物增强提高了腐殖化率和腐殖化度。生物增强不仅促进了芳香结构和 CC 键的形成，还带来了 HA 中官能团不同的变化顺序。与对照组（CK，2.37 g/kg）相比，生物增强组（BA，7.51 g/kg）获得的 HA 明显更高。同样，BA 的 HA/FA（1.90）也高于 CK（0.62），并在第 40 天达到峰值 2.34。多酚腐殖化途径起着主要作用，而不管是否添加接种物。然而，外源微生物在初始阶段促进了蛋白质和碳水化合物的降解，前体（氨基酸和还原糖）的丰度增强了美拉德和多酚腐殖化途径。在后期多酚不足时，生物增强主要体现在美拉德腐殖化途径的加强上。这一发现有利于定向腐殖化过程在食物垃圾堆肥中的应用。
