Browse Our Biology and Life Sciences Journals
Biology is a study of living objects and their life processes. It examines all aspects of living organisms such as their occurrence, classification, internal and external structure, nutrition, reproduction, inheritance, etc. The term “biology” is commonly replaced by the terms “life sciences” and “biological sciences.” There are dozens of branches of biology. Some of the major ones include:
Biology and Life Sciences
Abstract
Epigenetic modifications are critical for the regulation of CD4+ T cell differentiation and function. Previously, we identified Acyl-CoA Synthetase Bubble Gum 1 (Acsbg1), a gene involved in fatty acid metabolism, as part of an epigenetic signature that was selectively demethylated in ex vivo isolated T helper 17 (TH17) cells. However, its functional relevance for CD4+ T cells remains incompletely understood. Here, we used in vitro differentiation assays and the adoptive transfer colitis model to investigate the role of Acsbg1 in the differentiation and function of TH1, TH17, and regulatory T (Treg) cells. In vitro, Acsbg1 was expressed in both TH17 and in vitro-induced Treg (iTreg) cells, whereas TH1 cells lacked Acsbg1 expression. Accordingly, Acsbg1 deficiency resulted in impaired TH17 and iTreg differentiation, whereas TH1 differentiation was unaffected. In vivo, upon adoptive transfer of Acsbg1⁻/⁻ Tnaïve cells, immunodeficient recipient mice exhibited an exacerbated colitis, characterized by an altered balance of TH17 and Treg cells, indicating that Acsbg1 expression is essential for optimal TH17 and Treg cell differentiation and function. Our findings highlight the importance of fatty acid (FA) metabolism in maintaining immune homeostasis by regulating T cell differentiation and provide novel insights into the metabolic targeting of inflammatory diseases.
Abstract
Aronia melanocarpa, a main constituent of black chokeberry, provides a rich source of bioactive molecules including polyphenols, flavonoids, and anthocyanins and has been used for long in traditional medicine due to its various health-promoting and disease-alleviating properties. The aim of our literature survey was to provide an actual update of evidence regarding the antibacterial activities exerted by Aronia melanocarpa and its potential application for the treatment of human bacterial pathogenic including food-borne infections. Our survey revealed that distinct ingredients in Aronia melanocarpa do not only inhibit growth of Gram-positive and to a lesser extent of Gram-negative bacteria, but also biofilm formation that is even more pronounced upon combined application. Furthermore, the anti-microbial effects against food-spoiling bacteria underscores the application of defined Aronia-derived molecules in food preservation decreasing the risk for transmission of food-borne pathogens and thereby, improving food safety. Notably, in vivo studies revealed that prophylactic Aronia juice application alleviated murine Listeria monocytogenes-induced enteritis, dampened growth of streptococci involved in dental caries development, and decreased the incidence of urinary tract infections in nursing home residents. In conclusion, Aronia-derived bioactive molecules exhibit promising anti-bacterial and disease-alleviating effects that should be further elucidated in clinical studies.
Abstract
Conventional laboratory mice are protected from oral Campylobacter jejuni infection due to colonization resistance (CR) mediated by their host-specific gut microbiota. Here, we used differential effects of distinct antibiotics on gut microbiota composition to identify microbial groups associated with CR against C. jejuni. Therefore, specific pathogen-free (SPF) mice were subjected to ampicillin plus sulbactam (A/S), ciprofloxacin (CIP), or vancomycin (VAN) via the drinking water for 28 days or left untreated before peroral C. jejuni challenge. Cultural analyses revealed that CR displayed by untreated mice was abrogated by A/S treatment, but only reduced in mice treated with CIP or VAN. Notably, differential analysis of antibiotic-induced microbiota changes and C. jejuni colonization dynamics identified lactobacilli and Clostridium leptum as key microbial groups that were associated with CR. Notably, the complete eradication of intestinal bacteria in A/S treated mice supported high intestinal C. jejuni colonization levels which triggered apoptosis and inflammatory responses accompanied by enhanced expression of matrix-degrading gelatinases in the colon. In conclusion, A/S treated mice represent a valuable infection model for the study of campylobacteriosis and the treatment of mice with specific antibiotics support the investigation of molecular mechanisms involved in CR against enteropathogens.
Abstract
The main problem in incorporating probiotics to hurdle matrix of foodstuffs is mitigation of viable count in the gastrointestinal tract. This study investigated the effects of various dairy matrices (sterilised milk, doogh, UF cheese, and yoghurt) on the viability of different probiotics under simulated gastrointestinal conditions. The results showed that the highest and the lowest viability in milk were related to Lacticaseibacillus paracasei and Bifidobacterium lactis, respectively. In doogh samples, no significant difference was observed. In cheese, the highest viability was observed in Lactobacillus acidophilus followed by Bifidobacterium longum, and L. paracasei. The viability of probiotics in yoghurt was less than in cheese and control treatment. These results indicated that milk and doogh are efficient delivery matrices for carrying probiotic cells.
Abstract
Natural preservatives are a suitable alternative to chemical preservatives in the food industry. To overcome its hydrophobic nature, insolubility in water, and degradation of free essential oils, liposomal encapsulation can be applied. In this study, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of free as well as liposomal rosemary essential oils (REO) were measured using disk diffusion and serial dilution method for Escherichia (E.) coli, Staphylococcus (S.) aureus, Salmonella (S.) enterica, Lactiplantibacillus (L.) plantarum, Aspergillus (A.) niger, and Saccharomyces (S.) cerevisiae. The antimicrobial properties of free and encapsulated essential oils were compared with sodium benzoate during thirty days of storage. Also, the release pattern of REO from liposomes was studied using dialysis membranes during the 30 days of storage. The results showed that the MIC of free and encapsulated REO is in the range of 3.5–5% and 5–6.5%, respectively. Gram+ Staphylococcus aureus was identified as the most sensitive, while Escherichia coli was the most resistant among the tested microorganisms to the essential oils. During refrigerated storage, free REO and sodium benzoate did not show any significant difference in antimicrobial properties (P > 0.05), while encapsulated REO significantly reduced the number of microorganisms in stored salad dressing (P ≤ 0.05).
Abstract
A successful spray-drying encapsulation is supported by the use of suitable matrix material. This research aimed to study the properties of maltodextrin-alginate matrix solution and its encapsulated iron powder. The study was conducted using the variation of iron concentration (8–20 mg g−1 matrix) and ratio of maltodextrin-alginate (10:0; 10:0.5; 10:1; 10:1.5; 10:2; 0:2). The results showed that a higher iron concentration increased the viscosity of the matrix solution, which led to the formation of higher moisture content particles, but reduced the encapsulation efficiency. Meanwhile, an increased ratio of maltodextrin-alginate allowed an increase in the viscosity of the matrix solution, the encapsulation efficiency, and the moisture content of the particles. However, iron loading capacity improved by increasing iron and alginate concentration. All samples appeared to be amorphous materials with a faster iron release at a pH 6.8 than that at a pH 1.2. In addition, incorporation of alginate improved the particle size, thermal stability, and antioxidant activity of the encapsulated iron powder. In brief, the improvement of the encapsulation efficiency, iron release, and thermal stability of spray-dried iron powder are highlighted in this study, which are important in food fortification and processing.
Abstract
This study successfully microencapsulated bitter gourd juice (EBG) and turmeric powder (ET) using chickpea protein isolate via freeze-drying, achieving encapsulation efficiencies of 85.3% and 89.5%, respectively. Particle size analysis revealed sizes of 3.69 µm for EBG and 4.97 µm for ET. FTIR confirmed the successful entrapment of core materials within the protein matrix. Although unencapsulated samples exhibited higher activity levels, the encapsulated forms also demonstrated significant antioxidant, antidiabetic, and anti-lipidemic properties, with effective protection and controlled release of active components in the gastrointestinal environment. This highlights their potential as functional ingredients for managing type 2 diabetes and hyperlipidaemia in food products.
Abstract
Basil (sweet basil, Ocimum basilicum L.) is an aromatic plant known for its culinary and traditional medicinal uses.
The content of estragole (methyl chavicol), a compound associated with a potential risk to human health, was determined in the essential oils of 12 samples of basil herb by gas chromatography with flame ionisation and mass spectrometry detection (GC-FID/MS) using an external standard method. The essential oils contained estragole at various levels, from 1.85 to 561.01 mg mL−1. Regarding the chemical profile, among the eleven essential oils, the compound with the highest relative proportion was linalool (29.1–70.3%), while estragole dominated in one essential oil with a relative proportion of 45.2%. All essential oils tested correspond to the European chemotype, which is characterised by a high content of linalool or a combination of linalool and estragole.
Given the recommendation for limiting human exposure to estragole, the safety of some essential oils may be of concern due to their high levels of estragole content.
The results indicate the importance of the chemical analysis of basil herb samples and the selection of chemotypes with low estragole content.
Abstract
Quaternary ammonium compounds (QACs) are the most significant disinfectants utilised to control the contamination of Staphylococcus aureus in food establishments. S. aureus is a significant pathogen that carries genes responsible for resistance to QACs, which pose a risk to public health and food safety. The objective of the study was to investigate the prevalence of QAC genes (qacA/B, qacC, qacG, qacH, qacJ, and smr) and benzalkonium minimal inhibitory concentration (MIC) values in S. aureus strains isolated from food products and food production facilities (n = 200). The analysis results indicated that the qacC gene was the most frequently detected, with a prevalence of 12%. The qacA/B, qacG, qacH, qacJ, and smr genes were identified at frequencies of 2%, 3%, 1%, 4.5%, and 5%, respectively. The highest MIC level was identified in the surface sample, which carried the qacG gene, at a concentration of 6.25 μg mL−1. The study's results highlight the potential risks associated with disinfectant resistance in food establishments. To prevent the transfer of disinfectant resistance genes, which have become a global risk, it is imperative that the rules of disinfectant usage are observed rigorously and that scientific research in this field is diversified.
Abstract
Bifidobacteria can maintain the ecological balance of intestinal microorganisms and are closely linked to the onset and progression of acute enteritis. Present research aimed to investigate the alleviation of DSS-induced acute enteritis by bifidobacteria. In vivo colonoscopy was performed in mice to observe the colorectal mucosa and the pathological damage of colon tissue and the colonic expression of tight junction proteins (Occludin, Claudin-1, ZO-1) and inflammatory factors (TNF-α, IL-1b, IL-6). The colon mucosa tissue samples were collected for bacterial 16S DNA sequencing and transcriptome sequencing. The intervention of bifidobacteria could effectively alleviate the trend of weight loss and colonic trauma in mice with DSS-induced acute enteritis. The bifidobacteria effectively restored expression of tight junction proteins (Occludin, Claudin-1, and ZO-1) and decreased expression of pro-inflammatory factors (TNF-α, IL-1b, IL-6). Bifidobacterium longum proved to be the most effective (P < 0.05). The altered composition of gut microbiota was reflected in the increase of the relative abundances of Dubosiella spp. in the B. longum treated group. The results suggested that bifidobacteria could repair intestinal barrier function, relieve the colon inflammation, and improve intestinal microbiota disorder; and B. longum demonstrated the best efficacy in mice with DSS-induced acute enteritis.
