猪粪堆肥过程中泰乐菌素去除及其微生态研究

发布时间：2018-04-24 16:23

  本文选题：猪粪 + 泰乐菌素　； 参考：《广西大学》2017年硕士论文

【摘要】：抗生素不仅用于人类疾病的治疗,同时被广泛应用于家畜畜禽的饲养当中,其产生的环境污染问题不容忽视,逐渐得到了广泛关注。大多数抗生素并不能够完全被动物充分利用,有相当一部分通过动物所产生的粪便或者是尿液等各种途径进入到了土壤、水体当中,还有随着有机肥的使用进入到农作物,最终会进入人体当中。因此其对养殖业、农业的可持续发展以及人类的健康会产生难以估量的影响。本研究针对家禽牲畜养殖当中所产生的粪便当中存在泰乐菌素的问题,首先在实验室内通过筛选得到两株具有较强泰乐菌素降解能力的菌株,在此基础上进一步细化研究,明确了两株菌对泰乐菌素的降解特性。根据前期实验室的研究成果,在室外以泰乐菌素作为大环内酯类抗生素模式抗生素,系统探究了添加外源的具有泰乐菌素能力的微生物对于猪粪堆肥当中泰乐菌素降解以及堆肥理化性质的影响,同时利用高通量测序,从基因水平上研究了猪粪堆肥过程中泰乐菌素去除的分子生物学机理。得到的主要结果如下:(1)通过对菌库当中的17株菌株进行泰乐菌素的筛选,筛选出A、B两株对泰乐菌素降解率最高的菌株。在对A、B菌株进行的培养基浓度、泰乐菌素浓度、温度、转速、pH、接种量对泰乐菌素的降解特性研究试验中,得到的对泰乐菌素降解效果的优化条件是:培养基浓度1/1 MM,泰乐菌素浓度50～200 mg·L-1,温度30～40℃,转速 150～170 rpm,pH 6～10,接种量 1%。(2)添加外源的微生物菌剂可以显著增加堆肥当中泰乐菌素的降解率,对堆肥的温度、含水率、pH值等也均具有一定的影响,而且能够降低堆肥完成时堆肥产品的毒性,对于堆肥的彻底完成具有一定的促进作用,堆肥最终完成时,添加外源微生物菌剂的处理小麦GI值为95.43%,显著高于其他处理。添加入微生物菌剂可以明显降低氮的流失,保障氮的再利用,堆肥最终完成时总氮的含量减少了30.05%,而TYL处理总氮降低了 32.14%,CK处理总氮降低了32.63%。微生物多样性测序结果表明,堆肥结束之后,堆体细菌群落多样性在属水平上的相对丰度有明显提高。其中,芽孢杆菌属(Bacillus)和假糖球芽孢杆菌属(Pseudogracilibacillus)可能对泰乐菌素的降解具有很好的促进作用。可以说,加入微生物在一定程度可以提高了堆肥当中泰乐菌素的去除效率,降低了堆体当中的毒害性。
[Abstract]:Antibiotics are not only used in the treatment of human diseases, but also widely used in the raising of livestock and poultry. The environmental pollution caused by antibiotics can not be ignored, and has been paid more and more attention. Most antibiotics can't be fully used by animals. Quite a few enter the soil through faeces or urine produced by animals, water bodies, and crops with the use of organic fertilizer. Will eventually enter the human body. Therefore, it will have incalculable effects on aquaculture, sustainable development of agriculture and human health. In order to solve the problem of the presence of tylosin in the feces produced in poultry livestock, two strains with strong degradation ability of tylosin were obtained by screening in the laboratory, and further detailed studies were carried out on this basis. The degradation characteristics of two strains of Tylosin were determined. Based on previous laboratory results, tylosin was used as a model antibiotic for macrolides outside. The effects of exogenous microbes with tylosin ability on the degradation of tylosin and physicochemical properties of pig manure compost were investigated systematically. Meanwhile, high-throughput sequencing was used to study the effects of adding exogenous microbes on the degradation of tylosin and the physical and chemical properties of the compost. The molecular biological mechanism of tylosin removal in pig manure composting was studied at the gene level. The main results were as follows: (1) by screening 17 strains of Tylosin from the bank, two strains of AHB with the highest degradation rate of tylosin were selected. In this paper, the degradation characteristics of Tylosin were studied by medium concentration, tylosin concentration, temperature, rotation speed, pH value and inoculation amount. The optimum conditions for the degradation of tylosin were as follows: the concentration of 1 / 1 MMM, the concentration of 50 ~ 200 mg / L ~ (-1) of tylosin, and the temperature of 30 ~ 40 鈩，

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