The purpose of this study was to investigate the degradation mechanism of Bifidobacterium on breast milk oligosaccharides (HMOs) and its application in infant nutrition. The composition and characteristics of HMOs were introduced, and the degradation mechanism of HMOs by Bifidobacterium was described, including intracellular and extracellular digestion and species-specific differences. The interaction between Bifidobacterium and Bacteroides in the process of degrading HMOs and its effect on intestinal microecology were analyzed. The effects of HMO formula milk powder on the intestinal microbiota of infants were discussed, including simulating breast milk composition, regulating intestinal flora and immune function, infection prevention, and brain development. Finally, the research results are summarized, and future research directions are proposed to provide directions for research in the field of infant nutrition.

The purpose of this paper is to comprehensively review the research progress of nattokinase in lowering blood lipid, including its source, structure and physicochemical properties, mechanisms of functions, clinical research status, and safety considerations, so as to provide reference for further research on the application of nattokinase in the treatment of dyslipidemia. Natto is a traditional Japanese fermented food, which is made from soybeans fermented by Bacillus natto. During the fermentation process, natto will produce a variety of biologically active substances, including nattokinase. Nattokinase (NK) is a serine protease with stable enzyme activity and good freeze–thaw tolerance, which exerts lipid-lowering and anti-atherosclerotic effects by activating hormone-sensitive lipase (HSL), inhibiting hydroxymethylglutaryl monoacyl coenzyme A reductase (HMG-CoA reductase), and enhancing lipoprotein lipase (LPL) activity. Large-scale clinical trials have confirmed that nattokinase significantly improves the lipid profile and reduces the atherosclerotic plaque area and intima-media thickness with a favorable safety profile. Compared with traditional lipid-lowering drugs (e.g., statins and fibrates), nattokinase has a multifaceted lipid-lowering mechanism and lower risk of side effects, which makes it suitable for patients intolerant of traditional drugs; when combined with natural products such as statins, fibrates, red yeast, and lifestyle interventions, it can play a synergistic role and further reduce the risk of cardiovascular disease. There are various types of nattokinase preparations on the market, and consumers should choose regular products with high activity and purity, and pay attention to their safety and applicable population.

The acceleration of industrialization and urbanization have led to the increasingly serious problem of waste gas pollution. Pollutants such as sulfur dioxide (SO₂), nitrogen oxides (NOx), volatile organic compounds (VOCs), ammonia (NH₃), formaldehyde (HCHO), and hydrogen sulfide (H₂S) emitted from industrial production, transportation, and agricultural activities have posed a major threat to the ecological environment and public health. Although traditional physical and chemical treatment methods can partially reduce the concentration of pollutants, they face three core bottlenecks of high cost, high energy consumption, and secondary pollution, and it is urgent to develop sustainable alternative technologies. In this context, probiotic waste gas treatment technology has become an emerging research hotspot due to its environmental friendliness, low energy consumption characteristics, and resource conversion potential. Based on the databases of PubMed, Web of Science Core Collection, Scopus, Embase, and Cochrane Library, this paper systematically searched the literature published from 2014 to 2024 according to the predetermined inclusion and exclusion criteria (such as research topic relevance, experimental data integrity, language in English, etc.). A total of 71 high-quality studies were selected from more than 600 studies for review. By integrating three perspectives (basic theory perspective, environmental application perspective, and waste gas treatment facility perspective), the metabolic mechanism, functional strain characteristics, engineering application status, and cost-effectiveness of probiotics in waste gas bioconversion were systematically analyzed. The main conclusions include the following: probiotics achieve efficient degradation and recycling of waste gas pollutants through specific enzyme catalysis, and compound flora and intelligent regulation can significantly improve the stability and adaptability of the system. This technology has shown good environmental and economic benefits in multi-industry waste gas treatment, but it still faces challenges such as complex waste gas adaptability and long-term operational stability. This review aims to provide useful theoretical support for the optimization and large-scale application of probiotic waste gas treatment technology, promote the transformation of waste gas treatment from ‘end treatment’ to ‘green transformation’, and ultimately serve the realization of sustainable development goals.

There is a lack of research on screening new strains of high-efficiency ammonia nitrogen degrading bacteria and treating high-concentration ammonia nitrogen aquaculture wastewater using immobilized composite bacteria. In this study, two strains capable of degrading ammonia nitrogen and nitrite were isolated from surface water. The species of the strains were accurately identified using ITS sequencing technology. Scp1 was identified as Pseudomonas and Scr1 as Rhodococcus erythropolis. Both strains were preserved. When the initial concentration of ammonia nitrogen was 1.50 mg/L, the degradation efficiency of ammonia nitrogen after 4 days of inoculation with Scp1, Scr1, and a combination of Scp1 and Scr1 was 90%, 93.3%, and 99.99%, respectively. Similarly, when the initial concentration of nitrite was 0.25 mg/L, the degradation efficiency after 4 days of inoculation with Scp1, Scr1, and a combination of Scp1 and Scr1 was 60%, 82%, and 97.2%, respectively. In addition, when the initial concentration of COD was 20 mg/L, the degradation efficiency after 6 days of inoculation with Scp1, Scr1, and a combination of Scp1 and Scr1 was 59%, 59.4%, and 93.75%, respectively. The results demonstrated that the combined bacteria, Scp1 and Scr1, had a better degradation effect on ammonia nitrogen, nitrite, and COD. Furthermore, a degradation test was conducted in a Penaeus vannamei breeding base, which showed good degradation effects. These findings provide theoretical support for the treatment of high ammonia nitrogen wastewater in aquaculture and have important practical applications.