Efficient Keratin Degradation Anaerobe And Effect On Methane Produce

According to the difficult degradable keratin international hot issues, by the anaerobic biological technology and in high temperature condition, high efficient degrading-keratin anaerobic mixedmicroorganisms were domesticated for the first time in laboratory. The microbial community composition of the mixedmicroorganisms M1-18 were analysised by DGGE technology and T/A clone library technology. Efficiency degrading-keratin anaerobic new bacteria named 18D-TA was isolated from the mixedmicroorganisms M1-18 through anaerobic membrane. The bacteria 18D-TA was the first reported bacteria of degrading-keratin ability in its place of general. The bacteria 18D-TA provided fresh microorganism resources to explore the degrading-keratin anaerobic mechanisms and offered a theoretical and technological infrastructure for the comprehensive utilization in many other industries, such as feed, amino acid fertilizer, leather hair removal pharmaceutical industries et al ,which was to make abandoned keratin reutilized, to have the important meaning to green sustainable development in our country economy.The results concluded: (1) Three high efficiency keratin-degrading anaerobe were builded from different biological environment by Hungate technique. The mixedmicroorganisms M1-18 was in-depth researched. The mixedmicroorganisms M1-18 could completely degrade unpretreated feathers during 15-16 hours in 55℃anaerobic condition. It could degrade cattle hair,pig hair, human hair, nail. The optimum temperature in feather keratin fermentation was 55℃, the optimal pH was 8.0-8.5. Intermediate metabolites of keratin fermentation were first key-studied, which focused on the content changing rule, such as sulfur elements, protein and amino acids, organic acid and ammonium nitrate nitrogen. Microbial components of the mixedmicroorganisms M1-18 was analyzed by DGGE technology, which belonged to Clostridiaceae family and Incertae Sedis XI family from Clostridiales order. (2) A keratin-degrading anaerobic bacteria was isolated from M-18, named 18D-TA. The sequence of M-18 shared 94.5% with Tepidimicrobium ferriphilum. The strains18D-TA could degrade unpretreatment feathers during 20h in 55℃anaerobic condition, which was first reported bacterium having the ablity of degrading-feathers in the Tepidimicrobium genera. Based on the physiological, biochemical characteristics and phylogenetic analysis ,the strain 18D-TA may be suspectedly identified as one of new strain of Tepidimicrobium genera, but some further identify were needed ,such as DNA-DNA hybridization.(3)These tests were researched that the influence of degrading-keratin anaerobic bacterium to different substrates ferment producing methane.35℃, the anaerobic degrade-keratin bacterium could greatly improve decomposition rate and biological conversion of the proteins in the pig mature, which had stimulative effect to methanogenesis in anaerobic fermentation, but had side effects to chicken-feather fermentation; 55℃, the degrading-keratin bacterium could degrade feathers in short time, improve feathers utilization ratio and biological conversion ratio, which had significantly stimulative effect, but the effect to pig manure fermentation were relatively weak. Degrading-Keratin anaerobic bacterium had different effects in different temperature for different substrates, and the phenomenon was very interesting, which was worth in-depth research on studying the influence of different temperature and matrix to the degrading-feather anaerobic bacterium ,so as to explore the mystery of the keratin anaerobic degraded and provide theoretical foundation for degrading-keratin anaerobic bacterium in many potential applications.