土霉素菌渣源酵母菌的筛选及其培养条件的优化

Screening of yeast from oxytetracycline fermentation residue and optimization of the fermentation conditions

【背景】随着制药行业的蓬勃发展,中国每年产生大量的抗生素菌渣,已造成了不可忽视的环境污染和资源浪费等问题。由于抗生素菌渣中含有丰富的蛋白质等有机物质,利用其蛋白质等进行二次生产或将成为解决抗生素菌渣处理问题的一种有效方法。【目的】从土霉素菌渣中筛选出天然酵母菌菌株,并利用土霉素菌渣作为酵母菌生长的主要培养基成分,通过其培养条件的优化,实现土霉素菌渣的资源化利用。【方法】以土霉素菌渣为样品,运用稀释涂布法进行酵母菌的筛选,通过其形态学观察和18S rRNA基因序列分析等方法对菌株进行鉴定。通过单因素试验与Box-Behnken Design试验结合,对培养条件进行优化,确定筛选菌株在以土霉素菌渣为主要成分培养基中的最佳生长条件。【结果】筛选的土霉素菌渣源酵母菌为一株希腊接合囊酵母菌(Zygoascus hellenicus)Y1,其最佳培养条件为:土霉素菌渣添加量为5%,葡萄糖添加量为0.5%,接菌量为2%,在pH 5.0、32℃、160 r/min条件下培养24 h。【结论】筛选到一株希腊接合囊酵母菌Y1,该菌能够很好地利用土霉素菌渣进行生长,实现了土霉素菌渣的资源化利用,大大减少了菌渣的排放,也为后续制备菌渣酵母膏奠定了基础。

[Background]With the development of pharmaceutical industry,an enormous amount of antibiotic fermentation residue is produced every year in China,which has caused environmental pollution and waste of resources.However,the residue is rich in proteins and other nutrients which can be used for secondary production,making it possible for effective utilization of the residue.[Objective]To screen yeast from oxytetracycline fermentation residue and optimize the culture conditions of the yeast in the medium with the residue as the main component for resource utilization of oxytetracycline fermentation residue.[Methods]Yeast strain was screened from oxytetracycline fermentation residue with the serial dilution-agar plating method.The strain was then identified through morphological observation and 18S rRNA sequence analysis.Single-factor experiment and Box-Behnken design were used to optimize the culture conditions and determine the optimal growth conditions of the strain in the medium with oxytetracycline fermentation residue as the main component.[Results]The Zygoascus hellenicus Y1 strain was screened out.The optimum culture conditions are as follows:oxytetracycline fermentation residue at 5%,glucose at 0.5%,inoculum at 2%,pH 5.0,32℃,160 r/min,24 h.[Conclusion]Y1,which can make full use of the oxytetracycline fermentation residue for growth,was screened out,realizing the resource utilization of the residue and reducing the discharge of bacterial residue.The result lays a foundation for the preparation of yeast extract with oxytetracycline fermentation residue.