Castro-Ramos Job Jonathan, Solís-Oba Aida, Solís-Oba Myrna, Calderón-Vázquez Carlos Ligne, Higuera-Rubio Jesús Mireya, Castro-Rivera Rigoberto
Instituto Politécnico Nacional, Centro de Investigación en Biotecnologia Aplicada, 90700, Tepetitla de Lardizábal, Tlaxcala, Mexico.
Universidad Autónoma Metropolitana, Unidad Xochimilco, Ciudad de Mexico, Mexico.
AMB Express. 2022 Dec 28;12(1):162. doi: 10.1186/s13568-022-01486-8.
Anaerobic digestion (AD) has recently been studied to obtain products of greater interest than biogas, such as volatile fatty acids (VFAs) and phytoregulators. The effect of the initial pH of cow manure and the fermentation time of the AD on the microbial composition, VFAs, indole-3-acetic acid (IAA) and gibberellic acid (GA) production was evaluated. The cow manure (7% solids) was adjusted to initial pH values of 5.5, 6.5, 7.5, and 8.5, and the AD products were analyzed every four days until day 20. The initial pH and the fermentation time had an important effect on the production of metabolites. During AD, only the hydrolytic and acidogenic stages were identified, and the bacteria found were from the phyla Firmicutes, Bacteroidetes, Actinobacteria, and Spirochaetes. The most abundant genera produced in the four AD were Caproiciproducens, Clostridium sensu stricto 1, Romboutsia, Paeniclostridium, Turicibacter, Peptostreptococcaceae, Ruminococcaceae and Fonticella. The highest amount of VFAs was obtained at pH 8.5, and the production of the acids was butyric > acetic > propionic. The maximum production of GA and IAA was at an initial pH of 6.5 on day 20 and a pH of 5.5 on day 4, respectively. There was a strong correlation (> 0.8) between the most abundant microorganisms and the production of VFAs and GA. The anaerobic digestion of cow manure is a good alternative for the production of VFAs, GA and IAA.
最近对厌氧消化（AD）进行了研究，以获得比沼气更具吸引力的产物，如挥发性脂肪酸（VFAs）和植物调节剂。评估了牛粪初始pH值和AD发酵时间对微生物组成、VFAs、吲哚-3-乙酸（IAA）和赤霉素（GA）产量的影响。将牛粪（7%固体含量）调节至初始pH值5.5、6.5、7.5和8.5，并每四天分析一次AD产物，直至第20天。初始pH值和发酵时间对代谢产物的产生有重要影响。在AD过程中，仅鉴定出水解和产酸阶段，发现的细菌来自厚壁菌门、拟杆菌门、放线菌门和螺旋体门。四个AD中产生的最丰富的属是产己酸菌属、严格梭菌1、罗姆布茨菌属、类芽孢杆菌属、Turicibacter、消化链球菌科、瘤胃球菌科和丰蒂塞拉菌属。在pH 8.5时获得的VFAs量最高，酸的产生顺序为丁酸＞乙酸＞丙酸。GA和IAA的最大产量分别在第20天初始pH值为6.5时和第4天pH值为5.5时。最丰富的微生物与VFAs和GA的产生之间存在很强的相关性（＞0.8）。牛粪的厌氧消化是生产VFAs、GA和IAA的良好替代方法。
