Selenium nanoparticles (SeNPs) are gaining importance in the food and medical fields due to their antibacterial properties. The microbial inhibition of these kinds of particles has been tested in a wide range of Gram (+) and Gram (−) pathogenic bacteria. When SeNPs are synthesized by biological methods, they are called biogenic SeNPs, which have a negative charge caused by their interaction between surface and capping layer (bioorganic material), producing their high stability. This review is focused on SeNPs synthesis by bacteria and summarizes the main factors that influence their main characteristics: shape, size and surface charge, considering the bacteria growth conditions for their synthesis. The different mechanisms of antimicrobial activity are revised, and this review describes several biosynthesis hypotheses that have been proposed due to the fact that the biological mechanism of SeNP synthesis is not fully known.

This research explored the potential of plant antimicrobial compounds as natural alternatives to synthetic antimicrobials in the food and pharmaceutical industries, emphasizing the urgent need to combat antimicrobial resistance. It detailed various mechanisms by which these plant-derived compounds inhibit microbial growth, including disrupting cell membrane integrity, impeding cell wall and protein synthesis, and preventing biofilm formation, ultimately leading to bacterial cell death. This study highlighted the specific effects of plant antimicrobials on bacterial cells, such as inhibiting biofilm formation, cellular respiration, and cell motility, while also modulating oxygen consumption and reactive oxygen species generation, which are vital in addressing biofilm-mediated infections. Additionally, these compounds can regulate the expression of virulence factors and efflux pumps, enhancing antibiotic efficacy. A bibliometric analysis revealed a growing trend in research output and international collaboration, particularly from China and the United States, with key journals including “Frontiers in Microbiology” and “Antimicrobial Agents and Chemotherapy.” The analysis identified six clusters related to plant antimicrobial research, underscoring the need for further investigation into the mechanisms and applications of these bioactive compounds. In conclusion, understanding the action of plant antimicrobials is important for their effective application in combating antimicrobial resistance.

Health benefits of probiotics and production of inhibitors of angiotensin converting enzyme (ACE) released during milk fermentation are well known. That is why in this investigation the proteolytic profile and ACE inhibitory capacity of peptide fractions from protein hydrolysis of milk during fermentation processes was analyzed. Milk fermentation was carried out inoculating 10⁶ CFU of L. rhamnosus GG, S. thermophilus SY-102 and with both bacteria. The proteolytic profile was determined using: TNBS, SDS-PAGE and SEC-HPLC techniques. In vitro ACE inhibition capacity was measured. The pH of 4.5 was reached at 56 h when the milk was fermented with L. rhamnosus, at 12 h with S. thermophillus and at 41 h in the co-culture. Production of free amino groups corresponded with the profile of low molecular weight peptides observed by SDS-PAGE and SEC-HPLC. Co-culture fermentation showed both the highest concentration of low molecular weight peptides and the ACE inhibitory activity (>80%). Results indicated that the combination of lactic cultures could be useful in manufacture of fermented milk with an added value that goes beyond basic nutrition, such as the production of ACE-inhibitory peptides.

Many studies have reported the benefits of probiotic microorganisms and the production of angiotensin-converting enzyme (ACE) inhibitors. Determining the proteolytic and ACE inhibition capacities during whey fermentation was the goal of the study. Lacticaseibacillus rhamnosus GG, Streptococcus thermophilus SY-102, and both bacteria together were initially inoculated into whey, reaching an initial concentration of 10⁸ CFU per milliliter in each fermentation system. Through the use of TNBS, SDS-PAGE, and SEC-HPLC methods, the proteolytic profile was examined. An in vitro investigation was performed to test the ACE inhibition capacity. With S. thermophilus, the logarithmic phase of microbial development was shorter than with L. rhamnosus (6 and 12 h, respectively). The logarithmic phase in the co-culture fermentation, however, was extended to 24 h. There were no significant differences in pH between the fermentations. However, the co-culture had a greater concentration of protein hydrolysis (453 ± 0.06 μg/mL), as indicated by the amount of free amino groups. Similarly, this fermentation produced more low molecular weight peptides. The higher inhibition activity, which increased at the conclusion of the fermentation with the co-culture and reached 53.42%, was influenced by the higher peptide synthesis. These findings highlighted the significance of creating useful co-culture products.

This work analyzed the antidiabetic activity of peptides from whey proteins after hydrolysis by Lactobacillus rhamnosus GG and Streptococcus thermophilus SY-102, emphasizing the differences between the proteolytic systems of both bacteria. Peptide fractions from whey proteins may have biological functions, such as antidiabetic functions, which inhibit the DPP-IV enzyme, and lactic acid bacteria could release them. A whey solution of 10% was fermented with selected lactic acid bacteria in monoculture and coculture, analyzing kinetic parameters and the proteolytic profile, using the 2,4,6-trinitrobenzene sulfonic acid technique for free amino groups’ determination and Tris-tricine polyacrylamide gel electrophoresis. An in vitro inhibition assay of the DPP-IV enzyme was used. The kinetic parameters showed a faster duplication rate in the monoculture with L. rhamnosus GG than in the co-culture, which was related to lactic acid production. Co-culture does not have the highest production of free amino groups and peptides. Still, peptide fractions with lower molecular weight (<2 kDa) were found and showed a high DPP-IV inhibitory capacity that was maintained from the middle of the fermentation to the end (55.4%). In comparison, the monoculture of L. rhamnosus GG increased from 0 to 63.3%. This demonstrates that the proteolytic capacity and the proteolytic system of each lactic acid bacteria determine the structure of the released peptides.

Background: Colorectal cancer (CRC) is the second and third most frequent cancer in women and men, respectively; indeed, CRC is placed as the fourth world's most deadly cancer (after lung, liver, and stomach cancer). The incidence of CRC is strongly influenced by nutrition and the high fat/high carbohydrate Western-style diet. CRC is one of the most intensively studied cancer types, partly because of its high prevalence, but also because of the existence of its precursor lesions, tubular or villous adenomas, and more recently serrated adenomas. The morphological steps in the adenoma-carcinoma sequence have been elucidated at a molecular level, which has allowed the identification of the genes responsible for CRC. Review and Conclusions: The main aim of this review is to provide data regarding the pathophysiological characteristics, molecular mechanisms as well as carcinogenic and chemopreventive agents for CRC, with emphasis on evidence supporting their efficacy. These compounds may modulate multiple signaling pathways involved in cell proliferation and apoptosis in transformed cells, they also enhance the host immune system and favor an effective treatment. Despite promising results from experimental studies, only a limited number of these compounds have been tested in clinical trials. The mechanistic spectrum and specificity of the action of phytochemicals represent a complex and evolving field of research.