Pei Yaxin, Zhao Sijie, Chen Xiang, Zhang Jiran, Ni Hongyuhang, Sun Mengxiao, Lin Hui, Liu Xinyu, Chen Hongge, Yang Sen
Department of Microbiology, School of Life Sciences, Henan Agricultural University, Key Laboratory of Agricultural Microbial Enzyme Engineering (Ministry of Agriculture), Zhengzhou, China.
Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
Front Nutr. 2022 May 19;9:880488. doi: 10.3389/fnut.2022.880488. eCollection 2022.
Insects are a potential alternative protein source to solve the food shortage crisis. Previous studies have illustrated that probiotics can improve the substrate conversion efficiency of insects and increase insect protein content. However, the effects of probiotics on insect physiology and nutrient metabolism are still not well understood. Here, the black soldier fly larvae (BSFL), (Diptera: Stratiomyidae), was used as a study subject to deeply investigate the specific interaction among a novel probiotic, EEAM 10B (10B), intestinal microbiota, and the host. In this study, the effects of 10B on the survival and physiology of BSFL were first analyzed. It shows that 10B significantly elevated the substrate conversion rate, average dry weight, and protein content of BSFL by 5%, 0.13 g/pc, and 8%, respectively. Then, we assessed the effect of 10B on the microbial community composition in the gut and frass of BSFL using Illumina Miseq sequencing. It shows that 10B significantly altered the microbial composition of the gut, but not that of the frass. Pearson's correlation analysis further showed that the , , and were positively correlated with the survival rate, crude protein content, and substrate conversion rate of BSFL. To further investigate the effect of 10B on host metabolism, metabolic analyses on germ-free BSFL, monobacterial intestinal BSFL, and natural BSFL were also performed. The results proved that 10B (i) played a vital role in the survival of BSFL; and (ii) regulated the amino acid synthetic and metabolic process of BSFL, thus leading to the rise of the protein content of BSFL. In addition, vitamin backfill assays verified that the BSFL survival rate was significantly improved by supplying the germ-free BSFL with riboflavin, which further suggests that 10B determines the survival of BSFL delivering riboflavin. Overall, this study provides a reference for understanding the comprehensive contribution of a specific probiotic to its host.
昆虫是解决粮食短缺危机的一种潜在替代蛋白质来源。先前的研究表明，益生菌可以提高昆虫的底物转化效率并增加昆虫蛋白质含量。然而，益生菌对昆虫生理和营养代谢的影响仍未得到充分了解。在此，以黑水虻幼虫（双翅目：水虻科）作为研究对象，深入探究一种新型益生菌EEAM 10B（10B）、肠道微生物群和宿主之间的具体相互作用。在本研究中，首先分析了10B对黑水虻幼虫生存和生理的影响。结果表明，10B显著提高了黑水虻幼虫的底物转化率、平均干重和蛋白质含量，分别提高了5%、0.13克/只和8%。然后，我们使用Illumina Miseq测序评估了10B对黑水虻幼虫肠道和粪便中微生物群落组成的影响。结果表明，10B显著改变了肠道微生物组成，但未改变粪便中的微生物组成。Pearson相关性分析进一步表明，[具体微生物名称1]、[具体微生物名称2]和[具体微生物名称3]与黑水虻幼虫的存活率、粗蛋白含量和底物转化率呈正相关。为了进一步研究10B对宿主代谢的影响，还对无菌黑水虻幼虫、单菌肠道黑水虻幼虫和天然黑水虻幼虫进行了代谢分析。结果证明，10B（i）在黑水虻幼虫的生存中起着至关重要的作用；（ii）调节了黑水虻幼虫的氨基酸合成和代谢过程，从而导致黑水虻幼虫蛋白质含量的增加。此外，维生素回填试验证实，通过向无菌黑水虻幼虫提供核黄素，其存活率显著提高，这进一步表明10B通过输送核黄素决定了黑水虻幼虫的生存。总体而言，本研究为理解特定益生菌对其宿主的综合贡献提供了参考。
