沼液和香蕉秆压榨汁生产单细胞蛋白菌株的筛选

由于全球蛋白质缺乏,单细胞蛋白(Single cell protein,SCP)作为一种安全的食品添加剂和饲料,越来越受到人们的重视。尽管SCP大规模生产历史已有近百年,但是对各种优良生产菌株、潜在底物以及最优发酵条件的研究仍然是世界各国研究的热点。基于此,本研究以沼液和香蕉秆压榨汁为研究对象,对能利用其生长的菌株进行筛选,为进一步的单细胞蛋白生产提供参考。实验结果表明:酵母菌、芽孢杆菌都能利用沼液和香蕉秆压榨汁生长,但香蕉秆压榨汁不易保存,因此不宜作为发酵底物;热带假丝酵母Candida tropicalis在沼液中的生长能力强于酿酒酵母Saccharomyces cerevisiae Y49和毕赤酵母Pichia pastoris GS115;芽孢杆菌在沼液中的生长无规律,且易染杂菌,不适合实际生产应用。因此,沼液作为热带假丝酵母单细胞蛋白生产的培养基,不仅能为单细胞蛋白的生产提供原料,也有利于沼液的妥善处理,实现经济效益和环境效益的双赢。

Screening of Single Cell Protein Producing Strains by Biogas Slurry and Banana Pseudostem Pressed Juice

Due to the global shortage of protein,single cell protein (SCP) has been paid more and more attention as a safe food additive and feed. Although the history of large-scale production of SCP has been nearly a hundred years, the research on various excellent production strains, potential substrates, and optimal fermentation conditions is still a hotspot in the world. Based on this, this study selected biogas slurry and banana pseudostem pressed juice as research objects to screen strains which can be used to grow, providing a reference for the production of single cell protein in the future. The results show that both yeast and bacillus can grow in the biogas slurry and banana pseudostem pressed juice, but banana pseudostem pressed juice is not easy to preserve, so it should not be used as a fermentation substrate. The growth capacity of Candida tropicalis in biogas slurry is stronger than that of Saccharomyces cerevisiae Y49 and Pichia pastoris GS115. The growth of bacillus in biogas slurry is irregular and easy to be contaminated, so it is not suitable for practical production. Therefore, biogas slurry can be used as a culture medium for the production of single cell protein of C.tropicalis,which not only provides sufficient raw materials for the production of single cell protein, but also facilitates the proper disposal of biogas slurry, so as to achieve a win-win situation of economic and environmental benefits.