In Vitro Synergistic Antibacterial and Anti-Inflammatory Effects of Nisin and Lactic Acid in Yogurt against Helicobacter pylori and Human Gastric Cells.

Helicobacter pylori is a bacterium that naturally thrives in acidic environments and has the potential to induce various gastrointestinal disorders in humans. The antibiotic therapy utilized for treating H. pylori can lead to undesired side effects, such as dysbiosis in the gut microbiota. The objective of our study was to explore the potential antibacterial effects of nisin and lactic acid (LA) in yogurt against H. pylori. Additionally, we investigated the anti-inflammatory effects of nisin and LA in human gastric (AGS) cells infected with H. pylori. Nisin and LA combination showed the strongest inhibitory activity, with confirmed synergy at 0.375 fractional inhibitory concentration index. Also, post-fermented yogurt with incorporation of nisin exhibited antibacterial effect against H. pylori. The combination of nisin and LA resulted in a significant reduction of mRNA levels of bacterial toxins of H. pylori and pro-inflammatory cytokines in AGS cells infected with H. pylori. Furthermore, this also increased bacterial membrane damage, which led to DNA and protein leakage in H. pylori. Overall, the combination of nisin and LA shows promise as an alternative therapy for H. pylori infection. Additionally, the incorporation of nisin into foods containing LA presents a potential application. Further studies, including animal research, are needed to validate these findings and explore clinical applications.

Optimizing hormonal and amino acid combinations for enhanced cell proliferation and cell cycle progression in bovine mammary epithelial cells.

OBJECTIVE: The number of bovine mammary epithelial cells (BMECs) is closely associated with the quantity of milk production in dairy cows; however, the optimal levels and the combined effects of hormones and essential amino acids (EAAs) on cell proliferation are not completely understood. Thus, the purpose of this study was to determine the optimal combination of individual hormones and EAAs for cell proliferation and related signaling pathways in BMECs. METHODS: Immortalized BMECs (MAC-T) were treated with six hormones (insulin, cortisol, progesterone, estrone, 17ß-estradiol, and epidermal growth factor) and ten EAAs (arginine, histidine, leucine, isoleucine, threonine, tryptophan, lysine, methionine, phenylalanine, and valine) for 24 h. RESULTS: Cells were cultured in a medium containing 10% fetal bovine serum (FBS) as FBS supplemented at a concentration of 10% to 50% showed a comparable increase in cell proliferation rate. The optimized combination of four hormones (insulin, cortisol, progesterone, and 17ß-estradiol) and 20% of a mixture of ten EAAs led to the highest cell proliferation rate, which led to a significant increase in cell cycle progression at the S and G2/M phases, in the protein levels of proliferating cell nuclear antigen and cyclin B1, cell nucleus staining, and in cell numbers. CONCLUSION: The optimal combination of hormones and EAAs increased BMEC proliferation by enhancing cell cycle progression in the S and G/2M phases. Our findings indicate that optimizing hormone and amino acid levels has the potential to enhance milk production, both in cell culture settings by promoting increased cell numbers, and in dairy cows by regulating feed intake.

Apoptosis-Inducing Effects of Short-Chain Fatty Acids-Rich Fermented Pistachio Milk in Human Colon Carcinoma Cells.

Pistachio milk (PM), an extraction product of pistachio, is protein- and fat-dense food. Short-chain fatty acids (SCFAs) are known for inducing cytotoxicity and apoptosis in colon carcinoma cells. This study aimed to find an optimal combination of probiotics that can produce a higher amount of SCFAs in PM. In addition, the anti-cancer effect of fermented PM on human colon carcinoma cells (Caco-2) was determined. The combinations of probiotics were as follows: Streptococcus thermophilus + Lactobacillus bulgaricus (C); C + Lactobacillus acidophilus (C-La); C + Lactobacillus gasseri (C-Lg); C + Bifidobacterium bifidum (C-Bb). The results indicated that fermented PM was produced after a short fermentation time in all the probiotics combinations. C-Bb produced up to 1.5-fold more acetate than the other probiotics combinations did. A significant amount of cytotoxicity, i.e., 78, 56, and 29% cell viability was observed in Caco-2 cells by C-Bb-fermented PM at 1, 2.5 and 5%, respectively. C-Bb-fermented PM (5%) induced early and late apoptosis up to 6-fold. Additionally, Caco-2 cells treated with C-Bb-fermented PM significantly induced the downregulation of α-tubulin and the upregulation of cleaved caspase-3, as well as nuclear condensation and fragmentation. Our data suggest that fermented PM, which is rich in acetate, may have the potential as a functional food possessing anti-colon cancer properties.

Effects of Chitosan and Duck Fat-Based Emulsion Coatings on the Quality Characteristics of Chicken Meat during Storage.

Chicken meat is a popular food commodity that is widely consumed worldwide. However, the shelf-life or quality maintenance of chicken meat is a major concern for industries because of spoilage by microbial growth. The aim of this study was to evaluate the effects of chitosan and duck fat-based emulsion coatings on the quality characteristics and microbial stability of chicken meat during refrigerated storage. The coated chicken meat samples were as follows: control (non-coated), DFC0 (coated with duck fat), DFC0.5 (coated with duck fat and 0.5% chitosan), DFC1 (coated with duck fat and 1% chitosan), DFC2 (coated with duck fat and 2% chitosan), and SOC2 (coated with soybean oil and 2% chitosan). The results showed that the apparent viscosity and coating rate were higher in DFC2 than in other groups. Physicochemical parameters (pH, color, and Warner-Bratzler shear force) were better in DFC2 than those in other groups during 15 days of storage. Moreover, DFC2 delayed lipid oxidation, protein deterioration, and growth of microorganisms during storage. These data suggest that chitosan-supplemented duck fat-based emulsion coating could be used to maintain the quality of raw chicken meat during refrigerated storage.

Toxicity Assessment of a Single Dose of Poly(ethylene glycol) Diglycidyl Ether (PEGDE) Administered Subcutaneously in Mice.

Poly(ethylene glycol) diglycidyl ether (PEGDE) is widely used to cross-link polymers, particularly in the pharmaceutical and biomaterial sectors. However, the subcutaneous toxicity of PEGDE has not yet been assessed. PEGDE samples (500-40,000 µg/mouse) were subcutaneously injected into the paraspinal dorsum of BALB/c male mice. Cage-side observations were carried out with measurement of organ weight, body weight variation, and feed intake, as well as histopathological characterization on day 28 post-exposure. Mice that received 40,000 µg of PEGDE showed severe toxic response and had to be euthanized. Subcutaneous injection of PEGDE did not alter feed intake and organ weight; however, the body weight variation of mice injected with 20,000 µg of PEGDE was significantly lower than that of the other groups. Exposure to 10,000 and 20,000 µg of PEGDE induced epidermal ulcer formation and hair loss. The histology of skin tissue in mice administered with 20,000 µg of PEGDE showed re-epithelialized or unhealed wounds. However, the liver, spleen, and kidneys were histologically normal. Collectively, PEGDE, particularly above 10,000 µg/mouse, caused subcutaneous toxicity with ulceration, but no toxicity in the other organs. These results may indicate the optimal concentration of subcutaneously injected PEGDE.