Lignocellulose Biotechnology Laboratory, Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India.
BMC Microbiol. 2013 May 7;13:99. doi: 10.1186/1471-2180-13-99.
Composting is microbial decomposition of biodegradable materials and it is governed by physicochemical, physiological and microbiological factors. The importance of microbial communities (bacteria, actinomycetes and fungi) during composting is well established. However, the microbial diversity during composting may vary with the variety of composting materials and nutrient supplements. Therefore, it is necessary to study the diversity of microorganisms during composting of different agricultural byproducts like wheat bran, rice bran, rice husk, along with grass clippings and bulking agents. Here it has been attempted to assess the diversity of culturable bacteria during composting of agricultural byproducts.
The culturable bacterial diversity was assessed during the process by isolating the most prominent bacteria. Bacterial population was found to be maximum during the mesophilic phase, but decreased during the thermophilic phase and declined further in the cooling and maturation phase of composting. The bacterial population ranged from 10(5) to 10(9) cfu g(-1) compost. The predominant bacteria were characterized biochemically, followed by 16S rRNA gene sequencing. The isolated strains, both Gram-positive and Gram-negative groups belonged to the order Burkholderiales, Enterobacteriales, Actinobacteriales and Bacillales, which includes genera e.g. Staphylococcus, Serratia, Klebsiella, Enterobacter, Terribacillus, Lysinibacillus Kocuria, Microbacterium, Acidovorax and Comamonas. Genera like Kocuria, Microbacterium, Acidovorax, Comamonas and some new species of Bacillus were also identified for the first time from the compost made from agricultural byproducts.
The use of appropriate nitrogen amendments and bulking agents in composting resulted in good quality compost. The culture based strategy enabled us to isolate some novel bacterial isolates like Kocuria, Microbacterium, Acidovorax and Comamonas first time from agro-byproducts compost. These bacteria can be used as potential compost inoculants for accelerating composting process.
堆肥是可生物降解材料的微生物分解，由物理化学、生理和微生物因素控制。微生物群落（细菌、放线菌和真菌）在堆肥过程中的重要性已得到充分证实。然而，堆肥过程中的微生物多样性可能因堆肥材料和养分补充的种类而异。因此，有必要研究不同农业副产品（如麦麸、米糠、稻壳、草屑和膨松剂）在堆肥过程中的微生物多样性。在这里，我们试图评估在农业副产品堆肥过程中可培养细菌的多样性。
通过分离最突出的细菌来评估堆肥过程中的可培养细菌多样性。在中温阶段，细菌种群最多，但在高温阶段减少，在堆肥的冷却和成熟阶段进一步减少。细菌种群范围从 10(5)到 10(9)cfu g(-1)堆肥。优势细菌通过生化特征进行了表征，然后进行 16S rRNA 基因测序。分离的菌株，包括革兰氏阳性和革兰氏阴性菌，属于伯克霍尔德氏菌目、肠杆菌目、放线菌目和芽孢杆菌目，其中包括葡萄球菌属、沙雷氏菌属、克雷伯氏菌属、肠杆菌属、Terribacillus 属、Lysinibacillus Kocuria 属、微杆菌属、食酸菌属和丛毛单胞菌属等属。还首次从农业副产品制成的堆肥中鉴定出了 Kocuria、微杆菌属、食酸菌属、丛毛单胞菌属和一些新的芽孢杆菌属等属。
在堆肥中使用适当的氮添加剂和膨松剂可以获得高质量的堆肥。基于培养的策略使我们能够首次从农业副产品堆肥中分离出一些新的细菌分离株，如 Kocuria、微杆菌属、食酸菌属和丛毛单胞菌属。这些细菌可以用作潜在的堆肥接种剂，以加速堆肥过程。
