Search Results (179)

The chemical composition and bioactivities of dry methanol extracts from roots, leaves and fruits of Prangos trifida (Apiaceae), collected in Serbia, were investigated. LC-DAD-QTOF-MS/MS analysis revealed 30 compounds, primarily polyphenols and coumarins. The root and leaf extracts were rich in chlorogenic and/or 3,5-di-O-caffeoylquinic acid (18.20–26.14 mg/g extract), and the fruit extract in oxypeucedanin hydrate and prantschimgin (46.50 and 71.64 mg/g). The leaf extract exhibited the highest total phenolic content (62.86 mg quercetin equivalents/g), total antioxidant activity (FRAP = 0.71 mmol Fe²⁺/g) and DPPH radical scavenging ability (44.08 mg quercetin equivalents/g). Antimicrobial activity testing (11 bacteria and three yeasts, microdilution method) showed that the most active were the root and leaf extracts against Micrococcus luteus, Staphylococcus aureus, S. epidermidis and Candida albicans (MIC = 0.625–5 mg/mL). The fruit extract showed the strongest cytotoxicity against tested stomach, colon and hypopharynx cancer cell lines (MTT test), with the highest selectivity toward hypopharynx cancer FaDu cells (selectivity index 4.71; determined in relation to non-cancerous VERO cells). No antiviral activity against herpesvirus type 1 was found. The results indicate that P. trifida represents a promising source of polyphenols and coumarins, notably expanding current knowledge on its chemical composition and supporting its potential relevance for pharmaceutical and food industry applications. Full article

Chemical investigation of the marine sponge-derived Streptomyces xiamenensis 1310KO-148 afforded six polycyclic tetramate macrolactams (PTMs), including three known compounds (1–3) and three previously undescribed chlorohydrin-containing analogues, chlokamycins B–D (4–6). Their planar structures were elucidated by extensive analysis of 1D and 2D NMR spectra and HR-ESIMS data, while the relative configurations were assigned using NOESY correlations. The absolute configurations were further confirmed by electronic circular dichroism (ECD) calculations. Compounds 3–6 exhibited significant cytotoxic activity against 14 human cancer cell lines (GI₅₀ = 2.68–24.92 μM) and antibacterial activity against Staphylococcus aureus (MIC = 16.00–32.00 μg/mL) and Micrococcus luteus (MIC = 4.00–32.00 μg/mL) among six tested bacterial strains. Full article

Lactic acid bacteria (LAB) are widely used in food systems; among them, bacteriocin-producing strains have attracted attention for their potential in the biopreservation of dairy products. This study started from the detection of bacteriocin-encoding genes in eight probiotic Leuconostoc mesenteroides subsp. mesenteroides strains, previously isolated, identified, and characterized for antimicrobial activity. Results confirmed the presence of bacteriocin genes across the strains, with Ln.F5 harboring both mesB and lcnA genes, and three other strains, including the Ln.M14 strain, exclusively carrying the lcnA gene. The two strains, Ln.F5 and Ln.M14, were used, in single and mixed cultures, for the first time, as adjunct cultures in a model cheese. Their impact against Listeria spp., Staphylococcus aureus, Escherichia coli, Micrococcus luteus, and Brochothrix thermosphacta, and on volatile organic compounds (VOCs), during ripening and storage, was evaluated. Results showed high viability (9.2 Log CFU/g) of Leuconostoc spp. in model cheese, up to 60 days of storage, and Pulsed-Field Gel Electrophoresis (PFGE) profiles of the re-isolated bacteria confirmed the survival of the added strains. Furthermore, results indicated the inhibition of E. coli and Listeria spp. started from the 15th day of ripening in samples differently inoculated with the two Leuconostoc strains. Listeria spp. was completely inhibited starting from 15 days by Ln.M14, in single culture. The complete inhibition of S. aureus, M. luteus, and B. thermosphacta was detected after 30 days of ripening in samples differently inoculated with Ln.F5 and Ln.M14. The VOC analyses revealed more complex aromatic profiles in samples inoculated with Leuconostoc strains, which, along with the development of cheese eyes, confirmed the effect of the Leuconostoc strains in enhancing quality traits of cheeses. Full article

The human skin microbiome has gained considerable attention as a resource for the development of innovative probiotics for cosmetic purposes or promoting skin health. However, the evaluation of new probiotic strains to ensure their “generally recognized as safe” (GRAS) status remains challenging. Here, we have subjected the annotated draft genome sequences of four human skin-derived bacterial strains, namely Bacillus subtilis MBF10-19J, Micrococcus luteus MBF05-19J, Staphylococcus hominis MBF12-19J, and Staphylococcus warneri MBF02-19J, to bioinformatic analyses to detect the genes associated with important probiotic traits, as well as undesirable characteristics such as antibiotic resistance, virulence factors, and toxic metabolites. Each bacterium harbors at least one type of adhesin-encoding gene, while only S. hominis MBF12-19J and S. warneri MBF02-19J contain the putative genes encoding enzymes for metabolism improvement. In vitro assays, including antibiotic susceptibility and antimicrobial activity testing, revealed strain-specific safety characteristics that complement the genomic findings. With regard to antibiotic resistance determinants, S. hominis MBF12-19J showed the most favorable profile, S. warneri MBF02-19J and M. luteus MBF05-19J appeared suitable when used with appropriate caution, and B. subtilis MBF10-19J exhibited amoxicillin resistance, i.e., warrants careful evaluation. Further in vivo validation is needed to determine whether these strains do indeed comply with GRAS evaluation frameworks. Full article

Background: The scalp represents a distinct ecological niche within the skin, and the structure of its microbiota, together with the factors shaping it, is considered important for the maintenance of scalp health. Methods: This study systematically analyzed the bacterial and fungal community structures on the scalps of 63 healthy Chinese women aged 18–25, and examined their associations with scalp type, sensitivity, and lifestyle factors. Scalp samples were collected, questionnaire surveys were administered, scalp physiological parameters were measured, and high-throughput sequencing of 16S rRNA and ITS genes was performed. Results: The results showed that, in this unique scalp skin niche, the dominant bacterial phylum was Actinobacteria, while the dominant fungal phylum was Ascomycota. The predominant bacterial genera were Cutibacterium and Staphylococcus, and the fungal community was dominated by Malassezia. When scalp types were categorized according to sebum content, dry scalps showed enrichment of Micrococcus, Streptococcus, Delftia, Staphylococcus aureus, and Staphylococcus hominis, whereas oily scalps, on the other hand, are primarily colonized by Cutibacterium and Staphylococcus species. In addition, we observed microbial interactions under different physiological conditions. The relative abundance of Cutibacterium decreased with increasing scalp sensitivity. Higher psychological stress, insufficient sleep, and high-sugar/high-fat dietary patterns tended to coincide with shifts in the relative abundance of Malassezia, implying that these influences may act through fungal rather than bacterial components of the scalp microbiota. Scalp sensitivity showed the strongest association with β-diversity among the variables examined, although the effect size was modest and did not reach conventional significance in the multivariable PERMANOVA. Conclusions: In young women, the scalp constitutes a distinct cutaneous niche whose microbiota is jointly shaped by sebum level, barrier sensitivity, and lifestyle factors, with sensitivity emerging as one of the more influential dimensions of community variation. These findings provide guidance for future in-depth research on the scalp microbiome network and offer a foundational reference for preventing suboptimal and pathological scalp conditions. Full article

Antibacterial thin-film coatings are of increasing interest for enhancing hygiene in controlled environments such as commercial greenhouses. Phytopathogens including Pseudomonas syringae, and human pathogens such as Escherichia coli, Micrococcus luteus, and Staphylococcus aureus, frequently contaminate greenhouse environments. The present study aimed to develop and evaluate multifunctional magnetron-sputtered glass coatings with strong antimicrobial performance, deposited by physical vapor deposition to achieve precise control of film composition and uniform coverage of large substrates (≥0.25 m²), ensuring industrial-scale applicability. Thin films were fabricated by magnetron sputtering using multi-alloy targets composed of Cu, Sn, Zn, Al, Ni, Fe, Ti, Mn, Nb, or Co. Fourteen distinct coating compositions were characterized using high-resolution transmission electron microscopy, scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Antibacterial performance was evaluated against the following strains: E. coli (PCM 2560), M. luteus (PCM 525), S. aureus (PCM 2602), and P. syringae pv. tomato (IOR2146). Coatings prepared from 90%Cu-10%Sn, 90%Cu-10%Zn, and 80%Cu-20%Ti targets exhibited one of the highest antibacterial efficiencies. These coatings also showed strong mechanical durability and corrosion resistance. Our results indicate that coatings obtained from Cu-based multi-alloy targets by magnetron sputtering are promising candidates for use as durable, antimicrobial inner glass surfaces in future greenhouse applications. Full article

Intense training loads alter the skin microbiome and defence mechanisms in athletes, yet adaptation profiles remain insufficiently characterised. This study evaluated the relationships between skin bacterial microbiome structure, antimicrobial activity, dermcidin levels, and acne severity in male professional hockey players compared with amateur athletes and non-athletes. One hundred men (18–57 years) were examined and allocated to six subgroups by exercise intensity and acne status. Microbiota composition was assessed by culture-based methods and MALDI-TOF identification, antimicrobial activity measured spectrophotometrically, dermcidin quantified by ELISA, and sweat proteome characterised by HPLC-MS. Staphylococcus epidermidis and Micrococcus luteus predominated in all groups. Exercise intensity, rather than acne, was the main determinant of total bacterial colonisation, which increased approximately tenfold from non-athletes to professional hockey players. In non-athletes, higher antimicrobial activity correlated with greater acne severity, whereas in professionals this relationship was absent and dermcidin levels showed an inverse association with acne severity. Proteomic analysis identified 17 polypeptides; dermcidin and prolactin-inducible protein were dominant in all groups, and calprotectin (S100-A8/A9) was detected exclusively in healthy professionals. Full article

Multidrug-resistant (MDR) pathogens and biofilm-associated infections represent a major global health concern, particularly in the context of medical devices such as catheters, tubing, and blood sampling devices. Biofilms, responsible for up to 85% of human infections, confer a high level of microbial resistance and compromise device performance and patient safety. In this study, the antibiofilm potential of Syzygium aromaticum (clove) essential oil was investigated through an in vitro assay. GC–MS analysis revealed eugenol (72.77%) as the predominant compound, accompanied by β-caryophyllene (14.72%) and carvacrol (2.09%). The essential oil exhibited notable antimicrobial activity, producing inhibition zones of 30.5 ± 4.5 mm against Staphylococcus aureus, 24.5 ± 0.5 mm against Micrococcus luteus, 16.0 ± 2.0 mm against Escherichia coli, 13.0 ± 1.0 mm against Pseudomonas aeruginosa, 23.5 ± 1.5 mm against Candida albicans, and 24.0 ± 2.0 mm against C. glabrata. A marked reduction in biofilm biomass observed on polyvinyl chloride (PVC) surfaces. The application of clove essential oil as a coating for PVC-based medical devices remains a future possibility that requires formulation and in vivo testing. This strategy is proposed as potentially eco-safe, although environmental toxicity and biocompatibility have not yet been evaluated. It could contribute to the prevention of biofilm formation in arterial sampling systems and other healthcare-related materials, thereby enhancing device safety and longevity. Full article

Atopic dermatitis (AD) is associated with microbial dysbiosis and impaired skin barrier function. Topical therapies, such as moisturisers and antimicrobial fragrance compounds, may modulate the skin microbiome and support disease management. The objective was to evaluate how a moisturiser and a fragrance compound (farnesol) influence skin microbiome composition in individuals with AD and healthy controls. In a randomised, controlled, operator-blinded study, 15 AD patients and 15 healthy controls applied a moisturiser, farnesol, moisturiser + farnesol, or no treatment to defined skin areas over 7 days. Microbiome composition, alpha/beta diversity, and core taxa were analysed using shotgun metagenomics. At baseline, AD patients exhibited distinct microbial profiles, including elevated Staphylococcus aureus and Micrococcus luteus. Neither moisturiser nor farnesol significantly altered richness, beta diversity, or core taxa in either AD patients or controls. However, moisturiser use in healthy individuals modestly increased Shannon diversity, reflecting improved microbial evenness. Despite clear microbiome differences between AD and healthy skin, short-term topical treatment did not markedly shift microbial composition. The observed stability underscores the resilience of the skin microbiome and suggests that longer interventions or more targeted formulations may be necessary to influence microbial dysbiosis in AD. Full article

This study aimed to evaluate the impact of autochthonous strains (Pediococcus pentosaceus 128b, Latilactobacillus sakei S15, Lactiplantibacillus plantarum S91, L. plantarum S24 and Staphylococcus carnosus G109) used as mono and mixed starter cultures on the quality attributes of traditionally produced sucuk, a Turkish dry fermented sausage, in a local small-scale facility. At the end of ripening, samples underwent comprehensive microbiological and physicochemical analyses. The use of autochthonous starter cultures (ASC) showed no statistically significant influence on thiobarbituric acid-reactive substances and water activity value. Lower pH values were observed in groups with autochthonous lactic acid bacteria strains (ALABS) compared to the control group. However, ALABS inhibited Micrococcus/Staphylococcus growth by rapidly lowering the pH, except in the groups with S. carnosus G109. The use of ASC led to an increase in the L* values of sucuk samples, except monoculture L. plantarum S91. The correlation heat map illustrating the relationships between the starter cultures and volatile compounds revealed that all groups containing L. plantarum S91 exhibit a volatile compound profile different from other single or mixed cultures. According to the results of the principal component analysis performed to determine the relationship between the chemical groups of the starter cultures and volatile compounds, the groups containing L. plantarum S91 differed from the other groups and showed positive correlations with phenols, furans, acids, terpenes, aromatic hydrocarbons, ketones, nitrogenous compounds, esters, and aliphatic hydrocarbons. Full article

Sucuk, a type of dry fermented sausage, is generally consumed cooked, unlike many fermented sausage types. Therefore, alternative applications to prevent nitrosamine formation in fermented sausages such as sucuk are of great importance. This study aimed to determine the effects of black garlic (BG) and cooking time (0, 1, or 3 min at 180 °C) in sucuk. For this purpose, four different sucuk batters were prepared: FG1 (1% fresh garlic-control), BG1 (1% BG), BG2 (2% BG), and BG3 (3% BG). After ripening, the samples were cooked for different durations and subjected to nitrosamine analysis. Additionally, the study investigated the effect of BG on the qualitative properties of the ripened samples (uncooked). The results showed that the use of BG in sucuk led to a decline in lactic acid bacteria and Micrococcus/Staphylococcus counts (p < 0.05). The pH and residual nitrite levels in BG2 and BG3 were lower than those in FG1 and BG1 (p < 0.05). The TBARS value increased with increasing usage rate of BG (p < 0.05). BG2 and BG3 increased N-Nitrosodimethylamine (NDMA) compared to FG1 and BG1 (p < 0.05). Garlic treatment had no significant effect on the N-Nitrosodiethylamine (NDEA) (p > 0.05). As the cooking time increased, the NDMA and NDEA content increased (p < 0.05). The interaction between treatment and cooking time affected only N-Nitrosopiperidine (NPIP), and at the 3 min cooking time, BG3 exhibited a higher NPIP content than FG1, BG1, and BG2 (p < 0.05). As a result, BG2 and BG3 had a negative effect on some quality properties of sucuk, while FG1 and BG1 generally showed similar results. Additionally, BG2 and BG3 showed similar increases in NDMA content. Nitrosamine content increased with increasing cooking time, but BG3 was more effective in NPIP formation than BG2 after 3 min of cooking. Full article

In the current research a series of new copper(II) complexes with novel acylhydrazone ligands were synthesized and their antibacterial and anticancer activities were determined. The complexes were characterized by molecular spectroscopy (FT-IR and UV-Vis) and conductivity measurements. Additionally, their structure was confirmed by single-crystal X-ray analysis. The crystallographic data revealed that all compounds are mononuclear Cu(II) species. The Cu(II) ion is four-coordinated by the ONO donor set from mono-deprotonated hydrazone ligand and one Cl^¯ anion, forming distorted square-planar geometry. The biological studies revealed that the compounds exhibit high antimicrobial activity, especially against Gram-positive bacteria, in some cases greater than the reference substances, and better activity than free ligands. The tested complexes possessed the lowest MIC and MBC values towards Staphylococcus epidermidis ATCC 12228 and Micrococcus luteus ATCC 10240. Furthermore, they showed no toxicity towards normal cell lines. Full article

The emergence of multidrug-resistant microbes presents a serious public health threat that requires new antimicrobial methods. A potential solution to combat resistance involves using metal nanoparticles that possess improved biological characteristics. The researchers have synthesized gold nanoparticles (Au-NPs) using gamma irradiation of Polyacrylamide (PAM) at 5, 10, and 15 kGy doses and through Au/chitosan nanocomposite production methods. They have also assessed the antimicrobial and anticancer functions of the produced nanomaterials by testing them on various microorganisms and cancer cell lines. Gold nanoparticles exhibited strong antibacterial effects against multiple Gram-positive bacterial strains, including Bacillus subtilis, Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus mutans, as well as methicillin-resistant Staphylococcus aureus (MRSA). Escherichia coli showed a significant inhibition zone of 23 mm, and Salmonella spp. showed similar inhibition. The inhibition zone for Klebsiella pneumoniae ATCC 13883 revealed resistance. The Au-NPs/chitosan composite showed moderate antifungal effectiveness against Syncephalis racemosum and Aspergillus niger alongside Candida albicans and several other tested fungi. Au-NPs showed cytotoxicity to breast MCF-7 cells, as well as liver HepG-2 cells and colon HCT-116 cells. The combination of Au-NPs with chitosan demonstrated limited effectiveness in countering hepatitis A virus (HAV-10) and herpes simplex virus type 1 (HSV-1). The combination of gamma-irradiated Au-NPs with biopolymers like chitosan demonstrates significant promise in antimicrobial and anticancer biomedical applications. Full article

Bacteriocins from lactic acid bacteria have attracted considerable attention as natural alternatives to conventional antimicrobial agents. Weissellicin LM85, a bacteriocin purified from Weissella confusa LM85, has been less extensively studied in terms of its mechanism of action and potential applications. In this study, purified weissellicin LM85 exhibited potent inhibitory effects against Gram-positive bacteria, with minimum inhibitory and bactericidal concentrations determined against Micrococcus luteus MTCC106. Time-kill assays and fluorescence staining indicated a concentration-dependent reduction in cell viability, accompanied by membrane disruption. Further analyses revealed potassium ion efflux, dissipation of membrane potential (Δψ) and pH gradient (ΔpH), genomic DNA fragmentation, and pronounced morphological alterations in target cells. These findings are strongly suggestive of membrane-targeted bactericidal activity, likely involving pore-forming effects. In addition, weissellicin LM85 inhibited both growth and biofilm formation of Salmonella enterica subsp. enterica serovar Typhimurium ATCC13311 and Staphylococcus aureus subsp. aureus ATCC25923. Mechanistic analyses revealed the disruption of cell membrane integrity, leakage of potassium ions, cytoplasmic contents, and non-specific DNA degradation, indicating a multifaceted antibacterial mode of action. These findings highlight weissellicin LM85 as a promising natural antimicrobial with potential applications in food preservation and the control of foodborne pathogens and biofilm-associated infections. Further studies on cytotoxicity and in vivo efficacy are required to advance its practical application. Full article

The pharmaceutical industry faces various production challenges. Bioburden control is essential, and appropriate strategies and procedures must be implemented at all stages of production to prevent microbial contamination and comply with regulatory standards. Quality tools can provide important information for data management in production processes. The objective of this study was to compare two types of statistical process control charts (Laney’s U-chart and Bell distribution) in monitoring the bioburden of a buffer solution used as an input to produce an attenuated viral vaccine. Bioburden data for the buffer solution were obtained over a two-year period. The results showed that the analyzed products met the regulatory specifications, as 99% of them presented ≤ 10 colony-forming units (CFU)/100 mL after filtration. Various microorganisms were identified in the buffer solution, including species from the genus Bacillus spp., Micrococcus spp., Kocuria spp., Staphylococcus spp., and Acinetobacter spp. The Bell distribution proved to be statistically more suitable for application in the management of bioburden data for the buffer solution since the limits were closer to the specified value and could more effectively assist in the investigation of process deviations in the production of an attenuated viral vaccine. Full article