As a major source of microbes and their numerous beneficial effects, the gut microflora/microbiome is intimately linked to human health and disease. The exclusion of enteric pathogens by these commensal microbes partially depends upon the production of bioactive compounds such as short-chain fatty acids (SCFAs) and polyunsaturated fatty acids (PUFAs). These key intestinal microbial byproducts are crucial to the maintenance of a healthy gut microbial community. Moreover, SCFAs and PUFAs play multiple critical roles in host defense and immunity, including anti-cancer, anti-inflammation, and anti-oxidant activities, as well as out-competition of enteric bacterial pathogens. In this review article, we hereby aim to highlight the importance of SCFAs and PUFAs and the microbes involved in production of these beneficial intestinal components, and their biological functions, specifically as to their immunomodulation and interactions with enteric bacterial pathogens. Finally, we also advance potential applications of these fatty acids with regards to food safety and human gut health.

肠道菌群/微生物组是微生物及其众多有益作用的主要来源，与人类健康和疾病有着密切的联系。这些共生微生物对肠道病原体的排斥部分取决于生物活性化合物的生产，例如短链脂肪酸（SCFA）和多不饱和脂肪酸（PUFA）。这些关键的肠道微生物副产物对于维持健康的肠道微生物群落至关重要。此外，SCFA和PUFA在宿主防御和免疫中起着多种关键作用，包括抗癌，抗炎和抗氧化活性，以及​​肠细菌病原体的竞争优势。在这篇评论文章中，我们的目的是强调SCFA和PUFA以及生产这些有益肠成分所涉及的微生物的重要性，及其生物学功能，特别是它们的免疫调节以及与肠道细菌病原体的相互作用。最后，我们还推进了这些脂肪酸在食品安全和人体肠道健康方面的潜在应用。