Search Results (2,915)

The gut microbiota of insects, shaped by extensive coevolution, plays a crucial role in host adaptability and ecological expansion. The fall armyworm (Spodoptera frugiperda J.E. Smith), a highly polyphagous and migratory invasive pest, infests more than 350 plant species worldwide, resulting in substantial crop losses and increased reliance on pesticide applications. In this study, we employed 16S rRNA high-throughput sequencing to investigate diet-induced alternations in the gut microbial communities of larvae fed corn, rice, or an artificial diet. The results showed that diet significantly influenced microbial diversity, with rice-fed larvae exhibiting the highest richness. Firmicutes, Proteobacteria, and Cyanobacteria were the predominant bacterial phyla. Genus-level analysis revealed notable diet-dependent shifts, with Enterobacter and other genera (e.g., Ochrobactrum and Allorhizobium–Neorhizobium–Pararhizobium–Rhizobium) only detected in plant-fed groups. Additionally, current findings suggest that gut microbial genera are more prevalent when S. frugiperda larvae feed on rice plants than on corn plants or an artificial diet and are closely linked to their metabolic activities. Dominant microbial genera are expected to support essential metabolic processes and exhibit increased abundance on rice. These results indicate that the gut microbiome of S. frugiperda is diet-driven reorganization, potentially facilitating its polyphagy. This study extends the current understanding by elucidating the specific gut microbial taxa and their putative metabolic associations that are responsive to diet in S. frugiperda, thereby providing a theoretical basis for its polyphagous capability and underscoring microbiota-based strategies for sustainable pest management. Full article

Herbivorous animals rely on complex gastrointestinal systems and microbial communities to efficiently digest plant-based diets, extract nutrients, and maintain health. Recent advances in metagenomic technologies have enabled high-resolution, culture-independent analysis of gut microbiota composition, functional potential, and host–microbe interactions, providing insights into microbial diversity across the herbivore digestive tract. This review summarizes key findings on the gastrointestinal microbiota of herbivores, focusing on ruminant foregut and non-ruminant hindgut fermentation. Ruminants like cattle, sheep, and goats host microbiota enriched with fibrolytic and methanogenic microbes that facilitate fiber degradation and volatile fatty acid production, contributing significantly to energy balance. In contrast, non-ruminants such as horses and rabbits rely on hindgut fermentation, with distinct microbial taxa contributing to carbohydrate and protein breakdown. The review further explores how specific microbial taxa, including Prevotella, Fibrobacter, and Ruminococcus, correlate with improved feed efficiency and growth performance, particularly in ruminants. Additionally, the roles of probiotics, prebiotics, and symbiotics in modulating gut microbial composition and enhancing productivity are discussed. Despite significant advances, challenges remain in microbial sampling, functional annotation, and understanding the integration of microbiota with host physiology. The review emphasizes the potential of metagenomic insights in optimizing herbivore gut microbiota to improve feed efficiency, health, and sustainable livestock production. Full article

Ectropis grisescens (Lepidoptera: Geometridae) is a destructive pest in tea plantations, leading to significant economic losses through defoliation. Existing control strategies, including chemical insecticides and biological agents, are often limited by environmental concerns, resistance, and variable efficacy. Recent evidence suggests that bacteria influence insect physiology and could be leveraged for pest management, but the postmortem microbial ecology of E. grisescens remains uncharacterized. In this study, we employed 16S rRNA sequencing to investigate temporal changes in the bacterial communities of E. grisescens cadavers at 0, 7, and 21 days following cryogenic mortality. Our results indicate a time-dependent decline in microbial diversity, while species richness initially increased before subsequent reduction. The dominant endosymbiont Wolbachia gradually diminished after host death, whereas Enterobacter remained abundant. Notably, non-dominant genera including Lysinibacillus and Sporosarcina exhibited a transient increase in abundance at day 7 before reverting to control levels by day 21. This study presents the first comprehensive analysis of postmortem microbial succession in a lepidopteran system, highlighting dynamic shifts in bacterial composition and offering potential avenues for microbiome-based pest management strategies. Full article

Spinal cord injury (SCI) is a devastating neurological state that could lead to motor, sensory, and autonomic dysfunction. In addition to its direct impact on the central nervous system, SCI exerts systemic effects, including disruption of gut homeostasis and alterations in the gut microbiota, which can contribute to sustained inflammation and hinder functional recovery. While antibiotic administration during the acute phase of SCI is clinically indicated, it may exacerbate microbial dysbiosis. In this study, we investigate the combined effects of SCI and cefazolin treatment on the gut microbiome of female rats. Animals were assigned to three groups: NAÏVE (no intervention), SHAM (cefazolin only), and INJURY (T10 spinal cord contusion plus cefazolin). Cefazolin was administered for seven days after the injury, fecal samples were collected at baseline (day 0), and on days 7, 14, 21, and 28 post-SCI. DNA was extracted and subjected to 16S rRNA gene amplicon sequencing, followed by bioinformatic analysis. Our findings revealed significant microbial dysbiosis in the INJURY group, including reduced alpha diversity and distinct shifts in microbial composition. These changes were most prominent during the acute phase post-SCI. Our findings highlight the compounding effects of spinal trauma and antibiotic exposure on the gut microbiome and suggest that maintaining microbial stability may represent a promising avenue to support recovery after SCI. Full article

Chrysanthemum morifolium Ramat. is a major ornamental crop that suffers from diverse fungal, bacterial, viral, and insect pests, causing significant yield and quality losses. Between 2015 and 2025, rapid progress in molecular biology, genomics, and ecological regulation has advanced both fundamental research and applied control strategies. Multi-locus sequencing, multiplex PCR, and next-generation sequencing refined the identification of fungal and bacterial pathogens, while functional studies of WRKY, MYB, and NAC transcription factors revealed key resistance modules. Hormone-mediated signaling pathways, particularly those of salicylic acid, jasmonic acid, and abscisic acid, were shown to play central roles in host defense. Despite these advances, durable genetic resistance against bacterial pathogens and broad-spectrum defense against viruses remains limited. Novel technologies, including virus-free propagation, RNA interference, and spray-induced gene silencing, have shown promising outcomes. For insect pests, studies clarified the damage and virus-vectoring roles of aphids and thrips, and resistance traits linked to trichomes, terpenoids, and lignin have been identified. Biocontrol agents such as Trichoderma spp., Bacillus spp., predatory mites, and entomopathogenic fungi have also demonstrated efficacy. Future efforts should integrate molecular breeding, genome editing, RNA-based tools, and microbiome management to achieve sustainable chrysanthemum protection. Full article

Bovine respiratory disease complex (BRDC) is a leading cause of morbidity and mortality in pre-weaned calves, yet the role of commensal nasal microbiota in outbreak severity remains poorly understood. This study characterized nasal bacterial communities during two BRDC outbreaks of differing severity (moderate vs. severe) and at ~30 days post-treatment. Nasal swabs were collected from calves and analyzed using 16S rRNA gene sequencing (V1–V3 regions, Illumina MiSeq) and quantitative PCR targeting three major BRDC pathogens. Microbial community profiles differed between outbreak groups and across timepoints. Calves in the severe outbreak group exhibited lower microbial diversity compared to those in the moderate outbreak. In both groups, diversity significantly increased from outbreak to post-treatment. At the time of disease, nasal communities were dominated by the genera Mycoplasmopsis, Mesomycoplasma, and Caviibacter, with qPCR confirming Mycoplasma bovirhinis as the predominant species. These findings indicate that BRDC outbreaks in pre-weaned calves are associated with reduced microbial diversity and the dominance of pathogenic Mycoplasma species, with recovery characterized by greater bacterial diversity. Shifts in nasal microbiome composition between outbreak and post-treatment may reflect pathogen-driven disruption during disease and subsequent microbial community rebalancing. Full article

The gut microbiome possesses a diverse range of biological properties that play a role in maintaining host health and preventing disease. Gut microbial metabolites, including short-chain fatty acids, natural purine nucleosides, ellagic acid derivatives, and tryptophan metabolites, have been observed to have complex and multifaceted roles in the gut and in wider body systems in the management of disease, including cancer. Triple-negative breast cancer is the most aggressive subtype of breast cancer, with restricted treatment options and poor prognoses. Recently, preclinical research has investigated the antiproliferative potential of gut microbial metabolites against this type of breast cancer with promising results. However, little is understood about the mechanisms of action and molecular pathways driving this antiproliferative potential. Understanding the complex mechanisms of action of gut microbial metabolites on triple-negative breast cancer will be instrumental in the investigation of the combined administration with standard chemotherapeutic drugs. To date, there is a paucity of research studies investigating the potential synergistic interactions between gut microbial metabolites and standard chemotherapeutic drugs. The identification of synergistic potential between these compounds may provide alternate and more effective therapeutic options in the treatment and management of triple-negative breast cancer. Further investigation into the mechanistic action of gut microbial metabolites against this breast cancer subtype may support the administration of more cost-effective treatment options for breast cancer, with an aim to reduce side effects associated with standard treatments. Additionally, future research will aim to identify more potent metabolite–drug combinations in the mitigation of triple-negative breast cancer progression and metastasis. Full article

Background: The pathogenesis of various colon-related pathologies, including irritable bowel syndrome, uncomplicated diverticulitis, and tubular adenoma, remains unknown, primarily due to their multifactorial nature. These gastrointestinal diseases are increasing in prevalence in Western countries and are common conditions worldwide. Objective: To identify intestinal microbiota signs and their associations with the development of colonic pathologies, such as irritable bowel syndrome, uncomplicated diverticulitis, and tubular adenoma. Materials and Methods: An observational, prospective, cross-sectional study was conducted to compare the microbiome among three conditions via 16S rRNA sequencing of biopsy samples obtained via colonoscopy. Results: The microbiome of individuals with tubular adenoma was less diverse than that of patients with diverticulitis and irritable bowel syndrome, with a lower abundance of commensal bacterial genera, such as Catenibacterium, Bifidobacterium, and Faecalibacterium, and an increase in several genera with known pathogenic roles, including Escherichia–Shigella, Fusobacteria, Prevotella, and Haemophilus. No significant association was found between the type of pathology and the total pathogenic or commensal disease score; however, a ratio of 2.54 to pathogenic/commensal was observed in the IBS patient group. In contrast, in the diverticulitis and adenoma patient groups, this ratio was 8. Conclusions: These results provide evidence supporting the proposal that alterations in the colonic microbiome could be involved in various colonic pathogeneses and that an imbalance between commensal and pathogenic populations could be directly related to pathogenesis in the microsystem. It is important to highlight the need for future studies. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its progressive form, metabolic dysfunction-associated steatohepatitis (MASH), have become the leading causes of chronic liver disease worldwide, with increasing rates of cirrhosis, hepatocellular carcinoma, and cardiovascular complications. Pathogenesis involves a complex interplay of dietary excess, sedentary lifestyle, insulin resistance, adipose tissue dysfunction, and alterations in the gut microbiome, which collectively lead to hepatocellular stress, inflammation, and fibrogenesis. Despite ongoing advances in pharmacotherapy, lifestyle intervention remains the cornerstone of management. Evidence shows that sustained weight loss of ≥5% reduces hepatic steatosis, ≥7% improves necroinflammation, and ≥10% stabilizes or reverses fibrosis. Dietary strategies, including Mediterranean-style patterns, high-protein approaches, and intermittent fasting, have been shown to be effective in improving insulin sensitivity and reducing intrahepatic triglycerides. Exercise interventions, focusing on both aerobic fitness and resistance training, enhance metabolic flexibility and combat sarcopenia, thereby improving hepatic and systemic outcomes. Equally important are behavioral support, digital health tools, and multidisciplinary approaches that enhance adherence and address barriers such as socioeconomic disparities, limited access, and patient engagement issues. Personalized nutrition plans, integrating physical activity, and ongoing support for behavioral change are essential for long-term disease management. This review synthesizes current evidence on the roles of macronutrients, micronutrients, dietary quality, physical activity, and adjunctive behavioral strategies in managing MASLD. By translating mechanistic insights into practical, evidence-based recommendations, we aim to provide clinicians, dietitians, and exercise professionals with effective frameworks to slow disease progression and improve outcomes across diverse patient populations. Full article

This study determined the efficacy of in-feed supplementation of a medium-chain fatty acid, caprylic acid (CA), on the cecal colonization of multidrug-resistant (MDR) Salmonella Heidelberg (SH) and its effect on the cecal microbiome of commercial broilers. A total of 24, 4-week-old commercial Ross 708 chickens were randomly allocated to two replicates of four treatment groups in eight BSL2 isolators (3 birds/isolator): Negative control (NC), Positive Control (PC), Antibiotic group (AB), and caprylic acid (CA) groups. The birds received a Salmonella-free standard corn–soy-based diet, with the broilers in the AB receiving 50 g/ton bacitracin methylene disalicylate, and the CA group receiving caprylic acid (1% w/w), in feed from days 1 to 35. All birds, except those in the NC group, were challenged with ~3.7 log₁₀ CFU of MDR SH/5 mL by crop gavage on day 29. Cecal samples were collected 7 days after the challenge for SH recovery by direct plating and enrichment, as well as for DNA extraction for 16S rRNA gene amplicon sequencing. Compared to the PC group, a 3.6 log₁₀ CFU/g reduction in SH was observed in the CA group (p < 0.05). Although no significant effect of CA on cecal microbial composition was observed, a significant difference in taxonomic α- and β-diversities was observed in the AB. CA also resulted in significant differences in hub taxa compared to PC in the network association analysis, indicating a potential role for microbiome modulation in its mechanism of action. Full article

Functional bowel disorders (FBDs) are chronic gastrointestinal conditions characterized by recurrent symptoms associated with gut microbiota dysbiosis. Although accumulating evidence suggests that probiotics can improve symptoms in patients with FBD, the underlying mechanisms remain to be fully elucidated. In this randomized, double-blind, placebo-controlled clinical trial, 38 adults meeting the Rome IV diagnostic criteria of functional constipation (FC) and functional diarrhea (FD) received either a multi-strain probiotic complex or placebo for 8 weeks. Clinical outcomes were evaluated using the Irritable Bowel Syndrome Severity Scoring System (IBS-SSS), bowel habits questionnaire, and IBS Quality of Life (IBS-QoL) instrument. Fecal samples were collected at baseline and at week 8 for gut microbiota profiling via 16S rRNA gene sequencing and metabolomic analysis using gas chromatography–mass spectrometry. Probiotic supplementation significantly reduced the severity of abdominal bloating and its interference with quality of life, and improved the body image domain of the IBS-QoL. Beta diversity analysis showed significant temporal shifts in the probiotic group, while 16S rRNA sequencing revealed an increased relative abundance of Faecalibacterium prausnitzii and Blautia stercoris. Fecal metabolomic analysis further indicated elevated levels of metabolites implicated in the gut–brain axis. Multi-strain probiotic supplementation alleviated gastrointestinal symptoms and improved aspects of psychosocial well-being in adults with FBDs, potentially through modulation of the human gut microbiome. Full article

Gut microbial modulation through diet is central to human health and disease. Despite tremendous effort in understanding the impact of nutrients and drugs on the gut microbiota, and attempts to develop dietary strategies that facilitate gut-beneficial effects, several erroneous gut microbiota-associated concepts remain prevalent in popular belief. This article discusses widespread misconceptions about the gut microbiota, contrasting them with contemporary scientific facts. In this article, ten prevalent myths, including the obsolete 10:1 bacteria-to-human-cell ratio, the reductive categorization of microbes as ‘good’ or ‘bad’, and the discredited universal biomarker status of the Firmicutes/Bacteroidetes ratio in relation to metabolic diseases, have been debunked. Essential facts highlighting the context-dependency of the microbiome, considerable inter-individual heterogeneity, and dynamic reactivity to dietary changes are discussed. This questions the assumptions that increased diversity always signifies health, that probiotics are intrinsically safe, that fecal microbiota transplantation is a universal remedy, or that leaky gut syndrome constitutes a clearly defined diagnosis. It is highlighted that eubiosis and dysbiosis do not possess uniform criteria, and microbiome–drug interactions are extremely individualized. The gut microbiota operates as a dynamic, adaptive ecosystem, necessitating sophisticated, evidence-based methodologies for study and therapeutic application, transcending simplistic misconceptions in favor of tailored insights and therapies. Full article

In the Red List of Threatened Species, released by International Union for Conservation of Nature (IUCN), Paphiopedilum helenae has been classified as an endangered species. It exhibits exceptional decorative value and germplasm resource potential. To elucidate the ecological adaptation of this species and the characteristics of its rhizosphere microbiome, bacterial 16S rRNA and fungal ITS sequences of three wild populations of P. helenae were investigated using Illumina high-throughput sequencing technology and the microbial community structures and diversities were systematically compared. These three populations were spanned across distinct geographical locations in Longzhou County, Guangxi. The results showed that the bacterial community in the rhizosphere soil of P. helenae comprised 31 phyla, primarily including Actinobacteriota, Proteobacteria, Chloroflexi and Acidobacteriota. On the other hand, the fungal community consisted of 10 phyla, dominated by Ascomycota and Basidiomycota. There were significant differences in the diversity of rhizosphere microbes across different populations of P. helenae. The LG population had the highest bacterial richness (Chao index: 2912.71 ± 131.73; p < 0.05) and diversity (Shannon index: 6.40 ± 0.06; p < 0.01), while the MQ population had the lowest diversity (Shannon index: 3.47 ± 0.24; p < 0.01) of fungi. The degree of variation in fungal β-diversity was significantly higher than that of bacteria. Soil organic matter (SOM) and available nitrogen (AN) contents were the core factors shaping the microbial communities in the rhizosphere soil of P. helenae, which jointly explained 49.87% and 16.39% of variations in the bacterial and fungal communities. Furthermore, population-specific enrichment of functionally significant microorganisms was evident. Population MQ was enriched with plant growth-promoting and stress-resistant fungi, such as Geminibasidium, Trichoderma, etc. Population LG was enriched with oligotrophic bacteria (e.g., Patescibacteria), while population SL exhibited an overwhelming dominance of Ascomycota (93.25%) and enrichment of pathogenic fungal genus Nigrospora. This research revealed the variations in the functional adaptation strategy of P. helenae and the microbial communities in the rhizosphere soils across different geographical locations. This suggests that microbial community imbalance in rhizosphere soil may be one of the factors leading to the endangerment of this plant species. The study proposed a differentiated protection strategy for endangered plant species based on microbial resources. The results provide a theoretical basis for development of a “microorganism-assisted protection” strategy for ecological restoration and sustainable utilization of endangered orchid plants. Full article

Hidradenitis suppurativa (HS) is a chronic, recurrent, and highly debilitating inflammatory disorder of the pilosebaceous unit. Its pathogenesis is considered multifactorial, involving genetic, environmental, hormonal, lifestyle, and microbiome-related factors. The microbiota, defined as the collection of microorganisms, their genomes, and their interactions within a given environment, colonizes multiple sites of the healthy human body, which include the skin and gut, where it contributes to the maintenance of homeostasis. In HS, both skin and gut microbiota exhibit disruptions in composition and diversity, a state referred to as dysbiosis. Alterations in the expression of antimicrobial peptides in HS further implicate the microbiome in disease pathophysiology. In addition, chronic inflammation, bacterial biofilm formation, and dysbiosis are thought to contribute to the severity and recurrence of HS. Although the precise role of dysbiosis in HS pathogenesis remains unclear, several studies have demonstrated a reduction in cutaneous microbial diversity in HS patients, distinguished by an increased abundance of anaerobic and opportunistic bacteria and a reduction in commensal species. The intestinal microbiome has been even less thoroughly investigated, but available evidence suggests decreased overall diversity and richness, with enrichment of pro-inflammatory and depletion of anti-inflammatory bacterial taxa. This review aims to provide an overview of the current knowledge regarding the role of the microbiome in HS, with the goal of informing the direction of future research, including the potential utility of the microbiome as a biomarker for diagnosis and severity stratification in HS. Full article

Clostridioides difficile is an obligate anaerobe and is primarily transmitted via the fecal–oral route. Data characterizing the microbiome changes accompanying transitions from non-colonized to C. difficile colonized subjects are currently lacking. In this retrospective cohort study, we examined 16S rRNA gene sequencing data in a total of 481 fecal samples belonging to 107 patients. Based on C. difficile status over time, patients were categorized as Negative-to-Positive, Negative Control, and Positive Control. A linear mixed effects model was fitted to investigate the changes in the Shannon α-diversity index over time. Zero-inflated negative binomial/Poisson mixed effects models or generalized linear mixed models with negative binomial/Poisson distribution were used to investigate the changes in taxon counts over time among different groups. A total of 107 patients were eligible for the study. The median number of stool samples per patient was 3 (IQR 2–4). A total of 42 patients transitioned from C. difficile negative to positive (Negative-to-Positive), 47 patients remained negative throughout their tests (Negative Control) and 18 were always C. difficile positive (Positive Control). A significant difference in microbiome composition between the last negative samples and the first positive samples were shown in Negative-to-Positive patients, ANOSIM p = 0.022. In Negative-to-Positive patients, the phylum Pseudomonadota and family Enterobacteriaceae increased significantly in the first positive samples compared to the last negative samples, p = 0.0075 and p = 0.0094, respectively. Within the first 21 days, Actinomycetota decreased significantly over time in the Positive Control group compared to the other two groups (p < 0.001) while Bacillota decreased in both the Negative-to-Positive group and Positive Control. These results demonstrate that the transition from C. difficile negative to C. difficile positive is associated with alterations in gut microbial communities and their compositional patterns over time. Moreover, these changes play an important role in both the emergence and intensification of the gut microbiome dysbiosis in patients who transitioned from C. difficile negative to positive and those who always tested positive. Full article