Search Results (56)

To clarify the microbial contamination and wood degradation risk of the Nanhai No. 1 shipwreck hull and verify on-site antibacterial agent effectiveness, microbial samples were collected and analyzed via SEM, metagenomic sequencing, bacterial isolation, enzyme activity detection, and antibacterial experiments. The results showed that Actinomycetota was the dominant phylum, and Brachybacterium, Microbacterium, and Brevibacterium were the dominant genera. Seven bacterial strains were isolated and purified, among which Brevibacterium sp. (NH.SH-B6) had the strongest wood degradation ability, possessing cellulase, LiP, MnP, and Lac activities. When cultured with hull wood as the sole carbon source, LiP was the dominant degrading enzyme of NH.SH-B6, and its maximum enzyme activity was achieved under the optimal conditions of pH = 7, 10% NaCl, 1000 mg/L FeSO₄, and no PEG400 added. 50 mg/mL cinnamaldehyde and 0.5% isothiazolinone K100 had good inhibitory effects on the isolated bacteria, and bacterial proliferation was due to incomplete antibacterial agent spraying. This study clarifies the microbial degradation risk of the Nanhai No. 1 shipwreck hull and provides a scientific basis for optimizing the on-site protection strategy of the shipwreck. Full article

Copper supplements are prominent antibiotic alternatives in livestock production, but their excessive use poses environmental risks, necessitating safer substitutes. Potassium diformate (KDF), an organic acid salt, has shown potential as a feed additive, yet its effectiveness in copper-unsupplemented diets remains unclear. This study compared the effects of copper glycinate (Cu_Gly) and KDF on weaned piglets fed a copper-unsupplemented basal diet. Forty-five Meishan piglets were allocated to a control group (basal diet), a Cu_Gly group (basal diet + 60 mg/kg Cu_Gly), or a KDF group (basal diet + 10 g/kg KDF). The KDF group exhibited a lower feed conversion ratio (FCR) than the control group. Although no significant differences in average daily gain were observed, KDF supplementation significantly enhanced immune function by increasing plasma IgG and decreasing IgM, IL-6, and IL-1 levels compared to the control. 16S rRNA sequencing analysis revealed that the Control group was enriched with pathogenic genera (Staphylococcus, Escherichia-Shigella, Brevibacterium) in the ileum and cecum. Cu_Gly supplementation enriched Bacillus, Longispora, and Terrisporobacterin the ileum, while KDF increased the abundance of beneficial taxa (TM7, Nesterenkoniain the ileum; Lachnospiraceae_UCG-007 in the cecum). Correlation analysis showed that the abundances of Escherichia-Shigella and Staphylococcus were negatively correlated with IgG but positively correlated with IgM and IL-6. Cecal Lachnospiraceae_UCG-007 (enriched in the KDF group) was negatively correlated with IL-1. In summary, KDF improved feed efficiency and demonstrates superior immunomodulatory effects compared to Cu_Gly. The enrichment of bacteria linked to metal resistance in the Cu_Gly group suggested a potential drawback not associated with KDF. Therefore, KDF represented a viable and sustainable alternative to copper supplements, offering a combination of improved gut health, enhanced immunity, and a reduced environmental risk profile. Full article

Some microorganisms present in the cultivation environment serve as biocontrol agents and contribute to enhanced mushroom production. However, the native bacteria naturally associated with commercial cultivation bags of Pleurotus ostreatus, as well as their growth-promoting roles and underlying mechanisms, remain poorly understood. This study aimed to identify native bacteria that promote Pleurotus ostreatus development and to investigate the underlying mechanisms. Four native bacteria, including Brevibacterium epidermidis (P6), Acinetobacter soli (A7), Pseudomonas parafulva (A8), and Pseudomonas hunanensis (A12), were isolated based on their ability to promote mycelial growth of P. ostreatus. B. epidermidis P6 shortened complete mycelial colonization time from ~30 d to 14 d in dual cultivation bags. All four strains increased fresh mushroom yield, with B. epidermidis P6, A. soli A7, and P. parafulva A8 increasing the number of basidiomata, while P. hunanensis A12 enhanced their size. These strains produced exopolysaccharides that enhanced mycelial growth. Additionally, B. epidermidis P6, A. soli A7, and P. parafulva A8 also secreted extracellular crude proteins that also promoted mycelial growth. Bi-plates and further gas chromatography–mass spectrometry analysis demonstrated that volatile organic compounds from P. hunanensis A12, including acetone, 2-butanone, benzaldehyde, and 1-undecene, enhanced fungal mycelial growth. The mycelial growth rates of Ganoderma lucidum and Pleurotus pulmonarius were also enhanced by these four strains. These results reveal that four native bacterial strains promote mushroom development through complex mechanisms. Full article

Artisanal raw milk cheeses harbour complex microbial communities that drive cheese making and shape sensory quality. Previous work on Idiazabal cheese identified rennet as a major microbial source, although all reservoirs contributed to varying degrees. However, their impact in terms of enzyme-encoding genes related to technological quality of cheese remained unexplored. Building on that, this study draws on metagenome-assembled genomes (MAGs) from cheeses and dairy environments to comprehensively identify enzyme-encoding genes involved in key biochemical processes. In cheese MAGs (Lacticaseibacillus paracasei), protease-encoding genes were dominated by ATP-dependent metalloproteases (M41), carbohydrate-active enzyme-encoding genes (CAZymes) by glycoside hydrolases (GH) and glycosyltransferases (GT), while esterase, lipase, and related-enzyme-encoding genes were restricted to sparse ‘GDXG’, type-B and esterase D families. Dairy environments emerged as major reservoirs of enzyme-encoding genes, with notable differences among sample types (p ≤ 0.001). The richest sources of protease-encoding genes were grass (610 genes), linked primarily to Pantoea agglomerans, and rennet (318), mainly related to Basfia sp. and Moraxella sp., dominated by metalloproteases (M23, M38) and serine proteases (S15). The largest reservoirs of CAZyme-encoding genes were food contact surfaces (1550), associated mainly with Salinisphaera sp. and Dietzia sp., and rennet (1505), related to, e.g., Bacteroides pyogenes, Alloprevotella sp., and Lentilactobacillus buchneri. Food contact surfaces were also the richest source of esterase, lipase and related-enzyme-encoding genes (1209), mainly linked to Dietzia sp., Corynebacterium sp., and Brevibacterium aurantiacum. Similarly, aroma-related enzyme-encoding genes (e.g., oppA, pepA, GH13, esterase D) were consistently detected in environmental matrices. These results provide novel insights into dairy microbiomes as functional reservoirs of aroma precursors, revealing their relevance for artisanal PDO cheese production and future biotechnological applications. Full article

The vaginal microbiome plays a crucial role in maintaining host health by preserving a balanced microenvironment. Nevertheless, the definition of a “normal” vaginal microbiome remains controversial, as its composition varies depending on factors such as ethnicity and geographical origin. In most cases, members of the genus Lactobacillus predominate in healthy vaginal microbiomes, protecting against potential pathogens through specific mechanisms such as the secretion of lactic acid and bacteriocins, among others. A reduction in Lactobacillus abundance, accompanied by an increase in anaerobic organisms, predisposes the host to the development of various pathologies. Among these pathologies is infection with human papillomavirus (HPV) and the subsequent development of cervical cancer. A progressive decline in Lactobacillus has been observed as the lesion advances in different populations worldwide. In the case of the Mexican population, several Lactobacillus have been reported in healthy microbiomes: L. gasseri, L. fermentum, L. rhamnosus, L. jensenii, L. crispatus, L. delbrueckii, L. acidophilus, and L. brevis. In contrast, genera reported in dysbiosis include Sneathia, while Brevibacterium aureum and Brachybacterium conglomeratum have been associated with HPV16 infection and/or SIL. The mere presence of some bacteria is not sufficient to modulate the cellular activity of host cells; therefore, the expression, production and activity of different proteins could be affected by the vaginal microbiome. The impact of the microbiome on host cell function is the result of different metabolites produced by the bacteria, which suppress or activate different signaling and metabolic pathways. The molecular interactions between the host and microbiome, as well as their role in cervical carcinogenesis, are still unknown. In this review, we focus on the vaginal microbiome, HPV, and the impact that the interaction of the microbiome with HPV has in cervical cancer development. Full article

Background/Objectives: The vaginal microbiota constitutes a highly dynamic microbial ecosystem shaped by the distinct mucosal, hormonal, and immunological environment of the female genital tract. Accumulating evidence suggests that shifts in cervical microbial composition and function may influence host–microbe interactions and contribute to gynecological disease risk. Within this framework, the present study aimed to perform an in-depth genomic characterization of the cervical microbiota in a well-defined cohort of Greek women. The primary objective was to explore the functional microbial landscape by identifying dominant bacterial taxa, taxon-specific signatures, and potential microbial pathways implicated in cervical epithelial homeostasis, immune modulation, and disease susceptibility. Methods: Microbial genomic DNA was isolated from 60 cervical samples using the Magcore Bacterial Automated Kit and analyzed through full-length 16S rRNA gene sequencing using the Nanopore MinION™ platform, allowing high-resolution taxonomic assignment and enhanced functional inference. In parallel, cervical samples were screened for 14 HPV genotypes using a real-time PCR-based assay. Results: The cervical microbial communities were dominated by Lactobacillus iners, Lactobacillus crispatus, and Aerococcus christensenii, collectively representing over 75% of total microbial abundance and suggesting a functionally protective microbiota profile. A diverse set of low-abundance taxa—including Stenotrophomonas maltophilia, Stenotrophomonas pavanii, Acinetobacter septicus, Rhizobium spp. (Rhizobium rhizogenes, Rhizobium tropici, Rhizobium jaguaris), Prevotella amnii, Prevotella disiens, Brevibacterium casei, Fannyhessea vaginae, and Gemelliphila asaccharolytica—was also detected, potentially reflecting niche-specific metabolic functions or environmental microbial inputs. No HPV genotypes were detected in any of the cervical samples. Conclusions: This genomic profiling study underscores the functional dominance of Lactobacillus spp. within the cervical microbiota and highlights the contribution of low-abundance taxa that may participate in metabolic cross-feeding, immune signaling, or epithelial barrier modulation. Future large-scale, multi-omics studies integrating metagenomics and host transcriptomic data are warranted to validate microbial functional signatures as biomarkers or therapeutic targets for cervical health optimization. Full article

Drinking water pipe biofilms, comprising viable microorganisms, microbial residues, and organic/inorganic particulates, pose significant risks to water safety by promoting the proliferation of opportunistic pathogens, pipe corrosion, and degradation of water quality. Their formation is strongly influenced by environmental conditions within the piping system. However, there is a lack of systematic research investigating the potential correlations between biofilm microbiota and the oral microbiomes of intensively farmed swine, as well as the age-dependent regulatory mechanisms shaping aquatic microbial communities. This pioneering study conducted a comparative analysis of biofilm microbiota from swine house water pipes and oral microbiomes across three growth stages (30-day BBF, 70-day NBF, and 110-day FBF groups), yielding three key findings. First, the biofilm biomass and dominant bacterial genera (e.g., Brevibacterium in BBF vs. Brevundimonas in FBF) exhibited stage-specific variations associated with swine age. Second, while the oral microbiomes showed no significant taxonomic divergence at the phylum or genus level, they shared characteristic phyla, including Actinobacteria and Bacteroidetes, with pipe biofilms, indicating potential cross-habitat microbial interactions. Third, the antibiotic resistance gene (ARG) adeF was consistently detected at high prevalence across all biofilm groups. These findings offer new insights into microbial transmission dynamics and inform risk mitigation strategies for livestock water supply systems. Full article

Marine-derived Actinomycetota have emerged as promising sources of bioactive natural products, particularly filamentous actinomycetes (e.g., Streptomyces). However, members from non-filamentous genera have showed potential biotechnological importance. In this study, we performed a comprehensive genomic characterization of two bioactive Brevibacterium strains, Brevibacterium luteolum (B. luteolum) 26C and Brevibacterium casei (B. casei) 13A, isolated from two Red Sea sponges. Whole-genome sequencing and taxonomic analysis confirmed species-level identification, marking the first documented report of these species within the Red Sea ecosystem. The two strains displayed antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans. Additionally, functional annotation revealed multiple genomic islands (GIs) enriched with genes conferring heavy metal resistance, DNA repair enzymes, nutrient acquisition, and mobile genetic elements, highlighting potential evolutionary adaptations to the harsh physicochemical conditions of the Red Sea. Genome mining identified biosynthetic gene clusters, including those encoding ε-poly-L-lysine, tropodithietic acid, ectoine, and carotenoids. The comparative analysis of orthologous gene clusters from both strains and their counterparts from terrestrial ecosystems highlighted potential marine adaptive genetic mechanisms. This study highlights the biosynthetic potential of B. luteolum 26C and B. casei 13A and their ecological role as active competitors and potential defensive associates within the sponge microbiome. Full article

Previous studies of direct-fed microbial (DFM) supplements showed variable effects on the microbiota and physiology of dairy cows. The main aims of this study were to investigate the milk microbiota of cows supplemented with a lactobacilli-based DFM compared to untreated cows; describe the changes; and quantify the association between the taxa and cow productivity. The study followed seventy-five Holstein–Friesian dairy cows supplemented with a DFM over 16 months compared to seventy-five non-supplemented cows. Twenty-five cows from each group were sampled for microbiota analysis. The top taxa significantly associated with the variables were as follows: Age (Mammaliicoccus_319276, Turicibacter), milk production (Turicibacter, Bifidobacterium_388775), DIM (Stenotrophomonas_A_615274, Pedobacter_887417), milk fat percentage (Pseudomonas_E_647464, Lactobacillus), calendar month (Jeotgalicoccus_A_310962, Planococcus), milk protein percentage (Tistrella, Pseudomonas_E_650325), experimental group (Enterococcus_B, Aeromonas), SCC (Paenochrobactrum, Pseudochrobactrum), and trimester of pregnancy (Dyadobacter_906144, VFJN01 (Acidimicrobiales)). These were identified using multivariable analysis. Twenty-six genera were associated with the differences between experimental groups, including Pseudomonas, Lactococcus and Staphylococcus. Microbial taxa that changed in relative abundance over time included Atopostipes, Brevibacterium and Succinivibrio. Many of these genera were also part of the core microbiota. Supplementation with the DFM significantly altered the milk microbiota composition in the dairy cows, highlighting the impact of long-term DFM supplementation on microbial communities. Full article

Sixteen long-ripened, high-quality Cabrales cheeses from independent producers underwent a comprehensive biochemical and microbiological characterisation. Significant variations in total microbial counts and specific microbial groups were observed among the cheeses. A metataxonomic analysis identified 249 prokaryotic amplicon sequence variants (ASVs) and 99 eukaryotic ASVs, respectively, which were classified into 52 prokaryotic and 43 eukaryotic species. The predominant species included bacteria of the genera Tetragenococcus, Lactococcus (of which Lactococcus lactis was used as a starter), and Staphylococcus, followed by Brevibacterium and Corynebacterium species. The starter mould Penicillium roqueforti was highly abundant in all cheeses; Debaryomyces hansenii, Geotrichum candidum, and Kluyveromyces spp. constituted the subdominant fungal populations. Glutamic acid (≈20 mg g⁻¹) was the most abundant free amino acid in all samples, followed by lysine, leucine, and valine (≈10–13 mg g⁻¹). Moderate-to-high amounts of the biogenic amines tyramine and ornithine were detected. A large variation between cheeses of the main organic acids (lactic, acetic, or butyric) was detected. Differences between samples were also observed for the majority volatile compounds, which included organic acids, alcohols, esters, and ketones. Positive and negative correlations between bacterial and fungal species were detected, as well as between microbial populations and key biochemical markers. Among the latter, Tetragenococcus halophilus correlated positively with ethyl caprylate and hexanoic acid, and Loigolactobacillus rennini correlated positively with γ-aminobutyric acid. Conversely, Staphylococcus equorum showed a strong negative correlation with ethyl caprylate and capric acid. These microbial and biochemical insights enabled us to propose a microbiota-based starter culture comprising prokaryotic and eukaryotic components to enhance Cabrales cheese quality. Full article

Brevibacterium species are Gram-positive, non-sporulating, coryneform, aerobic rods that are catalase positive and exhibit a distinctive transition from diptheroid to coccoid morphology during culture. Infections by these species are seldom identified. Objective: This narrative review aims to present all the reported cases of Brevibacterium spp. infections in humans, focusing on data about epidemiology, antimicrobial resistance, antimicrobial treatment, and mortality. A narrative review based on a literature search of PubMed/MedLine and Scopus databases was performed. In total, 41 studies providing data on 42 patients with Brevibacterium spp. infections were included in the present analysis. The median age was 48 years, while 57.5% were male. The presence of a central venous catheter and malignancy, and end-stage renal disease on peritoneal dialysis were the main predisposing factors. Bacteremia was the most common type of infection, with peritoneal dialysis-associated infections being the second most common. B. casei was the most commonly identified species. Microbial identification required the use of advanced molecular techniques, such as 16s rRNA sequencing or matrix-assisted laser desorption/ionization time of flight mass spectrometry in most cases. Brevibacterium spp. was highly resistant to the combination of trimethoprim with sulfamethoxazole, clindamycin, and common beta-lactams. The most commonly used antimicrobials were vancomycin and aminoglycosides. The mortality was about 10%. Clinicians and laboratory personnel should consider this pathogen in the differential diagnosis in patients with malignancy or peritoneal dialysis-associated peritonitis. Vancomycin should be used for empirical treatment and while antimicrobial susceptibility testing results are pending. Full article

Histamine is a biogenic amine found across the phylogenetic spectrum, from plants to fish to animals. In farm animal production, the host’s production of histamine within the intestinal tract serves as a neurotransmitter, facilitating communication from the gut to the brain. Histamine functions additionally as a “bridging” chemical between the immune and nervous systems as it facilitates nervous system modulation of host immune response, thereby playing a critical role in host defense within the gut. Increased histamine levels within the gut, whether originating from food-borne sources or produced in situ, can lead to immune dysregulation and consequent physiological harm. As such, control of histamine within the gut can improve overall gut health across a broad range of species. In the present study, we utilized a Microbial Endocrinology-based approach as a platform technology to enable the discovery of unique histamine-degrading bacteria within the gut microbiota. Broiler chickens were fed, or not, a low or high histamine-supplemented diet from one day of age to up to 42 days in order to encourage the increased abundance of putative histamine-degrading bacteria. Intestinal contents were employed in a discovery protocol that involved repeated isolation rounds utilizing a histamine-supplemented minimal medium. We herein report the discovery that the genus Brevibacterium are capable of up to 100% degradation of histamine in vitro. Feeding experiments utilizing one of the identified Brevibacterium spp., a B. sediminis isolate, demonstrated that it reduced the amount of histamine in the gut of broilers fed a histamine-containing diet and enabled an improvement in growth as compared to non-B. sediminis-supplemented animals. As such, this study demonstrates the usefulness of a Microbial Endocrinology-based approach for the discovery of bacteria that may serve as potential probiotic candidates for the control of neurochemical-mediated interactions within the host, thereby improving host health. Full article

Plant-growth-promoting bacteria (PGPB) have beneficial effects on plants. They can promote growth and enhance plant defense against abiotic stress and disease, and these effects are associated with changes in the plant metabolite profile. The research problem addressed in this study was the impact of inoculation with PGPB on the metabolite profile of Salicornia europaea L. across controlled and field conditions. Salicornia europaea seeds, inoculated with Brevibacterium casei EB3 and Pseudomonas oryzihabitans RL18, were grown in controlled laboratory experiments and in a natural field setting. The metabolite composition of the aboveground tissues was analyzed using GC–MS and UHPLC–MS. PGPB inoculation promoted a reconfiguration in plant metabolism in both environments. Under controlled laboratory conditions, inoculation contributed to increased biomass production and the reinforcement of immune responses by significantly increasing the levels of unsaturated fatty acids, sugars, citric acid, acetic acid, chlorogenic acids, and quercetin. In field conditions, the inoculated plants exhibited a distinct phytochemical profile, with increased glucose, fructose, and phenolic compounds, especially hydroxybenzoic acid, quercetin, and apigenin, alongside decreased unsaturated fatty acids, suggesting higher stress levels. The metabolic response shifted from growth enhancement to stress resistance in the latter context. As a common pattern to both laboratory and field conditions, biopriming induced metabolic reprogramming towards the expression of apigenin, quercetin, formononetin, caffeic acid, and caffeoylquinic acid, metabolites that enhance the plant’s tolerance to abiotic and biotic stress. This study unveils the intricate metabolic adaptations of Salicornia europaea under controlled and field conditions, highlighting PGPB’s potential to redesign the metabolite profile of the plant. Elevated-stress-related metabolites may fortify plant defense mechanisms, laying the groundwork for stress-resistant crop development through PGPB-based inoculants, especially in saline agriculture. Full article

The composition of the intestinal microbiota can influence the metabolism and overall functioning of avian organisms. Therefore, the objective of this study was to evaluate the effect of three different probiotics and an antibiotic on the microbiomes of 1.400 male Cobb^® broiler raised for 42 days. The experiment was conducted with the following treatments: positive control diet (basal diet + antibiotic); negative control diet (basal diet without antibiotic and without probiotic); basal diet + Normal Avian Gut Flora (NAGF); basal diet + multiple colonizing strain probiotics (MCSPs); and basal diet + non-colonizing single strain probiotics (NCSSPs). The antibiotic (enramycin—antibiotic growth promoter) and probiotics were administered orally during all experiment (1 to 42 days), mixed with broiler feed. To determine the composition of the microbiota, five samples of ileal digesta were collected from 42-day-old chickens of each experimental group. The alpha and beta diversity of the ileal microbiota showed differences between the groups. MCSPs presented greater richness and uniformity compared to the positive control, negative control, and NCSSPs treatments, while the negative control exhibited greater homogeneity among samples than NCSSPs. MCSPs also showed a higher abundance of the genus Enterococcus. There were differences between the groups for low-abundance taxa (<0.5%), with NAGF showing higher levels of Delftia, Brevibacterium, and Bulleidia. In contrast, NCSSPs had a higher abundance of Ochrobactrum, Rhodoplanes, and Nitrospira. It was concluded that the treatments analyzed in this study induced modulations in the ileal microbiota of the chickens examined. Full article

In this experiment, we explored the chemical composition and community structure of Mulberry “Wuhedashi” (Morus alba L., hereinafter referred to as WHDS) in different stages and obtained data support for its resource utilisation. Five ripening stages were established: S1, deep-red stage; S2, red with black stage; S3, black with red stage; S4, black stage; S5, overripe stage. The results showed that there were significant differences in the indicators of WHDS in the different stages. Immature WHDS contains high levels of amino acids (2.14 ± 0.15 mg/g), organic acids (43.10 ± 0.75 mg/g), K (3019.52 ± 78.00 mg/L), and Ca (1617.86 ± 24.45 mg/L) and is an important source of amino acid and mineral supplementation for the body. Total phenolic compounds (26.15 ± 0.43 g/L), total flavonoids (2.46 ± 0.03 g/L), total anthocyanins (587.60 ± 7.38 mg/L), the ABTS radical scavenging rate (94.20 ± 2.18%), the DPPH radical scavenging rate (95.13 ± 1.44%), and total flavour compounds (1279.09 ± 33.50 mg/L) peaked at S4, which is the optimal stage for the consumption and processing of WHDS. High-throughput sequencing identified 10 dominant genera, including Bacillus, Brevibacterium, Pseudomonas, and Tatumella. Nesterenkonia was the most highly associated micro-organism. Bacterial genera such as Pantoea and Pseudomonas were significantly positively correlated with esters, enhancing the floral and fruity flavours of wine. The results of the study revealed the characteristics of WHDS in different stages, which can help to target the development of nutritious mulberry derivatives and provide a reference for enhancing the added value of mulberry. Full article