Bacterial quorum sensing (QS) is a cell-to-cell communication in which specific signals are activated to coordinate pathogenic behaviors and help bacteria acclimatize to the disadvantages. The QS signals in the bacteria mainly consist of acyl-homoserine lactone, autoinducing peptide, and autoinducer-2. QS signaling activation and biofilm formation lead to the antimicrobial resistance of the pathogens, thus increasing the therapy difficulty of bacterial diseases. Anti-QS agents can abolish the QS signaling and prevent the biofilm formation, therefore reducing bacterial virulence without causing drug-resistant to the pathogens, suggesting that anti-QS agents are potential alternatives for antibiotics. This review focuses on the anti-QS agents and their mediated signals in the pathogens and conveys the potential of QS targeted therapy for bacterial diseases.

Alpha-ketoglutarate (AKG) is a crucial intermediate of the Krebs cycle and plays a critical role in multiple metabolic processes in animals and humans. Of note, AKG contributes to the oxidation of nutrients (i.e., amino acids, glucose, fatty acids) and then provides energy for cell processes. As a precursor of glutamate and glutamine, AKG acts as an antioxidant agent as it directly reacts with hydrogen peroxide with formation of succinate, water, and carbon dioxide; meanwhile, it discharges plenty of ATP by oxidative decarboxylation. Recent studies also show that AKG has alleviative effect on oxidative stress as a source of energy and an antioxidant in mammalian cells. In this review, we highlight recent advances in the antioxidative function of AKG and its applications in animals and humans.

Type, quality, and origin of cereals in diets of poultry and pigs could influence gut microbes and affect their diversity and function, thereby impacting the intestinal function of the monogastric animal. In this review, we focus on the major carbohydrates in cereals that interact directly with gut microbes and lead to the production of key metabolites such as short-chain fatty acids (SCFA), and discuss how cereal fiber impact intestinal health of poultry and pigs. An overview of how the cereals and cereals-derived carbohydrates such as beta-glucans, resistant starch, cellulose, and arabinoxylans could promote intestinal health and reduce the use of in-feed antibiotics in animal production are presented. The metabolic pathway utilized by microbes and the mechanism of action underlying the produced SCFA on intestinal health of monogastric animals is also discussed.