一株解磷菌的筛选及其培养条件优化

发布时间：2018-07-12 17:13

  本文选题：解磷菌 + 巨大芽孢杆菌　； 参考：《浙江大学》2015年硕士论文

【摘要】：磷是植物生长发育不可缺少的营养元素之一,然而,我国农田土壤缺磷面积占农田总面积的2/3,施用磷肥是保证农业生产的重要手段。磷素在土壤中极易固定,我国磷肥当季利用率只有10%～20%,导致大量磷素以难溶态磷残留在土壤中,形成巨大的磷库。解磷微生物能够促进难溶性磷溶解,供植物吸收利用,因此,开发高效解磷微生物肥料是目前研究的热点。本研究以筛选高效解磷菌株,并利用食品工业产生的有机废水为营养来源优化其发酵培养条件为主要研究内容,以期为解磷菌的农业应用奠定基础,并实现废弃物的资源化利用。取得的主要研究结果如下:(1)筛选出一株具有较强解磷能力的微生物菌株:巨大芽孢杆菌(Bacillus megaterium)。该菌株摇瓶培养7d,对Ca_3(PO_4)_2的降解率达16.21%,对磷矿粉降解率达6.49%。(2)筛选出以味精发酵废液为主要营养源的巨大芽孢杆菌基础培养基配方;通过正交试验得优化配方为:牛肉膏1.0g、蛋白胨1.0g、味精废液稀释80倍、CaCO_31.0g、MgSO4·7H_2O1.0g、H_3BO_30.02g、H_2O1000mL。(3)单因子摇瓶培养试验结果表明:培养条件参数为:初始pH 7.0～7.5,温度30℃～35℃,培养时间约36h,接种量约5%,装液量约10%,转速180r/min。(4)摇瓶培养补料试验表明,采用优化配方培养9h时再补加原始配方中50%的味精废液,有利于提高巨大芽孢杆菌菌体数。(5)两步控制摇瓶培养试验表明,在培养前中期添加Mn~(2+)或在培养中期添加Ca~(2+)可显著提高巨大芽孢杆菌培养终点芽孢数,但初期添加Ca~(2+)会抑制菌体的生长;适当提高培养中后期的pH、温度及转速均能显著提高芽孢数。
[Abstract]:Phosphorus is one of the essential nutrient elements in plant growth and development. However, phosphorus deficiency in farmland soil accounts for 2 / 3 of the total farmland area in China. Phosphorus fertilizer is an important means to ensure agricultural production. Phosphorus is easy to be fixed in the soil. The utilization rate of phosphorus fertilizer in China is only 10% 20%, which leads to a large amount of phosphorus remaining in the soil with insoluble phosphorus, forming a huge phosphorus pool. Phosphorus-soluble microorganisms can promote insoluble phosphorus dissolution for plant absorption and utilization. Therefore, the development of high efficiency phosphorus-soluble microbial fertilizer is a hot research topic at present. In order to lay a foundation for the agricultural application of phosphorus releasing bacteria, the main research content of this study was to screen high efficient phosphorus releasing bacteria strains, and to optimize the fermentation and culture conditions by using organic wastewater produced by food industry as the nutrient source, in order to lay a foundation for the agricultural application of phosphorus releasing bacteria. And realize the resource utilization of waste. The main results are as follows: (1) Bacillus megaterium)., a microorganism strain with strong phosphorus solubilizing ability, was screened out. After 7 days of culture in shaking flask, the degradation rate of CaStu3 (PO4) 2 was 16.21 and the degradation rate of phosphate rock powder was 6.49. (2) the basic medium formula of Bacillus megaterium with MSG fermentation waste as the main nutrient source was selected. The optimum formula was obtained by orthogonal test as follows: beef paste 1.0 g, peptone 1.0 g, MSG waste liquid 80 times diluted CaCO31.0 g MgSO4 7H 2O 1.0 g H3BO30.02gStaH2O1000mL. (3) single factor shaking flask culture test showed that the culture conditions were as follows: initial pH 7.0, temperature 30 鈩，

本文编号：2117913