Search Results (6,429)

The anticancer activity of two novel microbial lipopeptide biosurfactants, amphisin and viscosinamide, was evaluated against human (A375) and murine (B16 4A5) melanoma cells. Normal human dermal fibroblasts (NHDFs) were used as a control. Cell viability was assessed using the MTT assay, while membrane integrity was analysed by the lactate dehydrogenase (LDH) release test. Early and late stages of apoptosis were investigated using Annexin V-FITC and Hoechst 33342 staining, respectively. In addition, the expression of apoptosis-related genes bax and bcl-2 was quantified by RT-qPCR. Finally, the wound healing (scratch) assay was performed to evaluate the effect of the tested lipopeptides on the migratory ability of melanoma cells. Both lipopeptides inhibited melanoma cell proliferation in a concentration- and time-dependent manner and exhibited significantly lower cytotoxicity toward NHDF cells, indicating selective antitumor activity. Viscosinamide exhibited stronger cytotoxic activity than amphisin. LDH release and fluorescence microscopy confirmed that the main mechanism of cytotoxicity was cell membrane damage and induction of apoptosis, including phosphatidylserine externalization and characteristic changes in the cell nucleus, such as chromatin condensation and cell nucleus fragmentation. Gene expression analysis demonstrated increased levels of bax and decreased levels of bcl-2, indicating activation of the intrinsic mitochondrial pathway of apoptosis. In addition, tested compounds effectively inhibited cell migration. The studies show that amphisin and viscosinamide exhibit selective anticancer potential related to the cell membrane and are promising molecules for further development as melanoma treatments. Full article

Fish are nutritionally valuable foods but are also highly perishable, representing a major research focus for the development of effective preservation strategies to delay spoilage while maintaining microbiological acceptability. In this context, edible coatings have gained increasing attention as clean-label tools to extend the shelf life of perishable foods. In this study, an alginate-based emulsion containing oregano essential oil (OEO) was applied to commercial frozen–thawed ready-to-cook (RTC) hake fillets, intentionally selected as a reproducible model system to evaluate coating performance under refrigerated conditions. Coated and uncoated fillets, stored at 4 °C for up to 7 days, were monitored over time for microbiological and physicochemical parameters, including microbial loads, pH, weight loss, and lipid oxidation (TBARS). Compared to uncoated samples, fillets treated with the alginate–OEO emulsion exhibited a marked delay in spoilage-related microbial growth, with a consistent inhibition of Pseudomonas spp. throughout the experimental period, while maintaining microbiological acceptability. Emulsion-based coated fillets also exhibited reduced lipid oxidation, a more uniform surface appearance with only minor visible color changes, and the absence of unpleasant off odors during the refrigerated storage. Overall, the results demonstrate that the alginate–OEO coating could represent an effective strategy for improving the microbiological and oxidative stability of RTC fish fillets under refrigerated conditions, with potential implications for extended shelf life and a reduction in food waste. Full article

Objectives: This randomized, controlled, parallel-group study was conducted to evaluate the effectiveness of daily almond consumption on acne lesion counts, skin hydration, sebum production, and skin microflora composition in 18–35-year-old young adults with acne vulgaris in Mumbai, India. Methods: A defined amount of whole, unsalted almonds with skin (60 g) was provided to the experimental group (n = 36). The control group (n = 38) received isocaloric cereal-pulse-based snack varieties. The primary endpoints were changes in inflammatory, non-inflammatory, and total acne lesion counts after 20 weeks of supplementation. Secondary endpoints included changes in facial sebum, hydration levels, skin morphology and microflora, and selected biochemical parameters. Results: At week 20, the almond group showed greater reductions in total lesion counts (−22.2% vs. −9.8%), inflammatory lesion counts (−8.3% vs. +12%), and non-inflammatory lesion counts (−26.1% vs. −20.4%) than controls. Objective lesion volume, area, and height measures for both single and clustered acne decreased in the almond group (p ≤ 0.001). Microbial diversity increased, with the Shannon index (2.6 to 3.4 (p = 0.039) and the Chao1 richness index (266.9 → 835.2; p < 0.001) showing improvements at endline. Moreover, significant post-intervention changes in the psychosocial outcomes, such as the acne-related quality of life scores (p < 0.001) and anxiety symptoms (p = 0.016), were observed in the almond group. Conclusions: Daily almond consumption reduced acne lesion count and improved skin microbial diversity and acne-specific quality of life, highlighting its potential to complement standard acne treatments and support skin health. Full article

Further understanding is needed regarding how biochar, over the long term, influences N₂O release and the associated communities of nitrifiers and denitrifiers in paddy soils. This field study examined the responses of these microbial communities to biochar applied for different durations (2016 or 2023) and at different doses (15 or 45 t·ha⁻¹), alongside a control (CK) without biochar addition. Relative to the control (CK), all biochar amendments led to a comprehensive enhancement of soil physicochemical properties. However, their impacts on N₂O fluxes diverged: cumulative emissions rose by 18.44% under the high-rate (45 t·ha⁻¹), first-year application (NB45) in 2023, but were suppressed across all other biochar treatments. Microbial community composition diverged markedly between treatment chambers, with the abundances of Nitrospira and Chloroflexota showing distinct patterns. In 2016, the two bacterial species exhibited significantly high abundance proportions, with maximum shares of 23.55% (2016, 45 t·ha⁻¹) and 12.16% (2016, 45 t·ha⁻¹), the most abundant in nitrification and denitrification, respectively, which influenced the certainty of changes in the microbial community structure. Biochar enhances nitrogen metabolism in nitrifying microorganisms but inhibits denitrification processes, with the biochar applied in 2023 having a remarkable effect. Overall, biochar application effectively enhances soil physicochemical properties, mitigates N₂O emissions over the long term, and modulates the community structure and functional traits of nitrifying and denitrifying microorganisms. These combined effects contribute to promoting environmental security for sustainable development within agricultural production systems while reducing the carbon footprint. Full article

Natural plant-derived extracts are increasingly recognized for their antimicrobial, antioxidant, and anti-inflammatory properties, making them promising candidates for the prevention and/or treatment of various diseases. Camellia sinensis Azorean Black Tea (ABT) and spent coffee grounds (SCG) were selected due to their high content of bioactive compounds, including catechins, theaflavins, chlorogenic acids, and caffeine, which have demonstrated potential against microbial infections. ABT and SCG extracts were applied to the hallux (big toe) skin of healthy volunteers for 8 h. Samples were collected before and after exposure and cultured on blood agar to determine colony-forming units (CFU), which were normalized to CFU/cm² of skin. No macroscopic skin alterations, thermographic changes, or early signs of inflammation were observed following exposure to these extracts. While the humid control and ABT exposure groups exhibited increased bacterial proliferation, SCG exposure resulted in bacterial levels statistically comparable to those of the dry control, with significantly lower bacterial growth than the humid control and ABT exposure groups. Overall, these findings add to the growing evidence supporting the use of natural extracts as sustainable options for skin protection and the regulation of microbial proliferation. Full article

The interruption of primary conservation procedures during food handling and preparation represents a critical operational phase for food microbiological safety, especially in environments characterized by repeated manipulation and continuous human presence. This study investigates the application of visible blue–violet light irradiation as a non-thermal process to mitigate microbial proliferation during post-processing handling of raw meat. Raw beef hamburgers, selected as the food model substrate, were subjected to irradiation using a blue–violet LED system operating in the 405–420 nm range and compared with non-irradiated controls under ambient and refrigerated conditions representative of real handling scenarios. Microbiological dynamics were evaluated through time-resolved enumeration of total aerobic mesophilic bacteria and Enterobacteriaceae, while concurrent measurements of moisture loss, texture, and color were performed to assess process-related effects on macroscopic product quality. Visible-light irradiation significantly reduced the rate of microbial growth during handling, with irradiated samples consistently exhibiting lower microbial loads than controls, particularly under ambient conditions (e.g., twofold after 24 h). Under refrigeration, irradiation contributed to stabilizing microbial levels over time, indicating a synergistic effect with low-temperature storage. From a process perspective, irradiation induced moderate and progressive changes in physicochemical attributes, primarily associated with surface dehydration and color variation, without abrupt quality degradation. These results demonstrate that visible blue–violet light irradiation can be integrated as a continuous, non-UV intervention to enhance the microbiological safety of raw meat during post-processing handling, supporting its potential role as an environmental control strategy in food-handling systems. Full article

With the widespread application of aniline, its improper discharge in industrial production and accidental leaks during production and transportation have led to contamination of soil and groundwater environments. Persulfate advanced oxidation technology shows great potential for remediating organic compound pollution. This study focused on a specific aniline-contaminated site to identify oxidants and activators, optimize their ratios, and investigate the effects of relevant factors on oxidative remediation. It also examined changes in the microbial communities at the site before and after contamination, as well as before and after oxidative remediation. We found that the removal efficiency of aniline was most significant when the molar ratio of the optimal oxidant (sodium peroxydisulfate (Na₂S₂O₈)) to the optimal activator (sodium hydroxide (NaOH)) was 1:1. When the initial aniline concentration in the soil reached 1000 mg/kg, it was necessary to increase the amount of the oxidant appropriately to maintain efficient removal. Environmental temperature and the content of organic matter in the soil had a relatively minor impact on the oxidation reaction. Following oxidation, the soil ammonia nitrogen content decreased, whereas nitrate and nitrite concentrations increased, with a significant rise in nitrate levels and substantial production of sulfate ion. Moreover, after aniline contamination, the microbial diversity in the soil of the site decreased, and the abundance of the genus Hydrogenophilus significantly increased. It is noteworthy that following oxidation treatment, the soil microbial community demonstrated a rapid trajectory of functional and structural recovery. Within five days of oxidant application, the community composition shifted from being predominantly composed of aniline-degrading taxa to closely resembling the original site in both community structure and inferred functional potential. Full article

Global climate change is intensively altering precipitation regimes, with profound consequences for the structure and function of various terrestrial ecosystems. Soil microbes are a key driver of organic matter decomposition and nutrient cycling; however, their response mechanisms to precipitation variations in fragile ecosystems remain poorly understood. We conducted an in situ precipitation manipulation experiment in a savanna ecosystem within the Yuanjiang dry-hot valley of southwest China since January 2014. We established three treatments: a control plot with natural precipitation (NP), precipitation exclusion by 50% (PE50), and precipitation addition by 50% (PA50). Soil samples were collected in mid-April and mid-August 2025. Using high-throughput sequencing technology, we systematically examined how precipitation variations affected soil microbial community structure and the underlying environmental drivers. The study results showed that both PA50 and PE50 treatments significantly altered the α- and β-diversity of bacterial and fungal communities (PERMANOVA, p < 0.05), marking a clear separation in overall soil microbial community structure among treatments. The bacterial community response was more pronounced to precipitation variations than the fungal community, and exhibited a non-linear response pattern. Both PE50 and PA50 treatments increased bacterial richness. In contrast, shifts in fungal diversity were season-dependent. The analysis results of Linear discriminant analysis Effect Size (LEfSe) revealed that the PE50 treatment enriched drought-tolerant taxa, such as Actinobacteria and Ascomycota. Conversely, the PA50 treatment favored moisture-preferring taxa, including Acidobacteria and Basidiomycota. Redundancy analysis (RDA) identified soil moisture (SM), dissolved organic nitrogen (DON), and soil organic carbon (SOC) as the key factors driving these community shifts. The relative importance of these drivers varied seasonally: SM was dominant in the dry season, while SOC and nutrient-related factors prevailed during the rainy season. This study elucidates the non-linear and seasonally contingent response mechanisms of soil microbial communities to precipitation variations in a fragile savanna ecosystem. Our findings provide a critical theoretical framework for predicting how the structure and function of vulnerable ecosystems may evolve under future climate change. Full article

Root-associated microbes play a crucial role in plant growth, stress resistance and the accumulation of secondary metabolites. In this study, LC-MS analysis revealed that soil provenance exerts a decisive influence on the content of flavonoids and astragalosides in Astragalus membranaceus. Transplant assays revealed that each soil type acted as a selective filter, assembling distinct microbial communities in both the rhizosphere and root of Astragalus membranaceus. The rhizosphere taxa selected from Yangling soil specifically enhanced flavonoid levels, whereas the root taxa selected from TanChang soil drove higher astragaloside accumulation. SourceTracker revealed that seedling root-endosphere ASVs served as the primary inoculum for later communities, confirming strong priority effects among early colonizers. Keystones tightly linked to both metabolite contents and biomass belonging to Caulobacteraceae, Acidimicrobiia, Sutterellaceae, Bradyrhizobium, Sphingomonas and Mesorhizobium were isolated, and the SynComs were constructed. In Tanchang soil, SynComs inoculation raised Astragaloside IV (AST IV) and Calycosin-7-glucoside (CAG) contents by 52.30% and 55.73%, respectively; in Yangling soil, the same consortium increased Astragaloside I (AST I), Astragaloside II (AST II), AST IV and CAG by 29.38%, 39.04%, 54.97% and 58.98% compared to the uninoculated controls. Collectively, our work charts the transplantation-driven dynamics of root-associated bacterial communities and medicinal metabolites, pinpoints keystones that govern ingredient accumulation and delivers validated microbial strains for enhancing the quality and pharmaceutical value of Astragalus mongholicus. Full article

Hot springs represent unique geothermal ecosystems where extreme physicochemical conditions intersect with remarkable microbial diversity and metabolic innovation. These natural laboratories harbor specialized communities of thermophilic and hyperthermophilic microorganisms that have evolved exceptional adaptations to elevated temperatures, extreme pH, and high salinity. This review synthesizes current understanding of hot spring systems as multifunctional natural resources, examining their roles in fundamental microbiology, biotechnology, and sustainable development. We explore the ecological principles governing microbial community assembly, the taxonomic and functional diversity of prokaryotic and eukaryotic microorganisms, and the genomic mechanisms underlying thermophilic adaptation. Hot springs yield enzymes revolutionizing molecular biology and industrial catalysis, bioactive metabolites with pharmaceutical potential, and novel bioremediation capabilities including plastic degradation. Beyond biological significance, these systems contain valuable minerals and rare earth elements, supporting an emerging bioeconomy integrating wellness tourism, bioprospecting, and sustainable resource extraction. However, critical knowledge gaps remain regarding viral ecology, horizontal gene transfer, eukaryotic diversity, and climate change impacts. We emphasize that hot springs merit renewed interdisciplinary attention as model systems for understanding extremophile physiology, early life evolution, and the development of nature-based biotechnological solutions. Realizing their full potential requires balanced management strategies that preserve ecosystem integrity while enabling responsible utilization of these irreplaceable geobiological resources. Full article

Continuous monocropping of cassava (Manihot esculenta Crantz) often leads to soil degradation and yield decline, commonly referred to as continuous cropping obstacles (CCOs), which are closely linked to changes in soil physicochemical properties and microbial communities. Biochar has been widely used as a soil amendment to improve soil quality and microbial activity and is considered a potential strategy for alleviating CCOs. Understanding the effects of biochar on soil bacteria and metabolites under field conditions is essential, as it provides insights into its practical effectiveness in reducing CCOs and improving soil health in cassava cultivation systems. In this study, a field experiment was conducted in a continuous cassava system to investigate the effects of a single biochar application rate on soil bacterial diversity, community composition, and metabolite profiles in both rhizosphere and bulk soils. High-throughput 16S rRNA gene sequencing and UHPLC–MS/MS-based non-targeted metabolomics were employed to analyze soil bacterial and metabolic patterns. Biochar was associated with increased α-diversity in rhizosphere soil and distinct shifts in β-diversity. Biochar increased the relative abundance of Chloroflexi and Actinobacteriota in the bulk soil, while Cyanobacteria and Nitrospirota were more abundant in the rhizosphere. Network analysis revealed the compartment-specific differences after biochar application, with higher network complexity in the rhizosphere and lower complexity in the bulk soil relative to the control. Metabolomic profiling identified 402 metabolites in positive ion mode and 357 in negative ion mode. In the rhizosphere, biochar-treated soil exhibited higher relative abundances of alkaloids (e.g., trigonelline, berberine, vincristine) and flavonoids (e.g., catechin, naringin, rutin, and taxifolin), which are commonly linked to plant stress responses. In the bulk soil, biochar application resulted in lower levels of several anthropogenic organic compounds (e.g., monobutyl phthalate, terephthalic acid, and p–toluenesulfonic acid). These findings provide preliminary field evidence that biochar application can lead to compartment-specific changes in soil bacterial communities and metabolite profiles. Such changes are closely related to soil quality and nutrient cycling, pointing to a possible role of biochar in mitigating soil degradation under continuous cassava cultivation. Full article

Age-related changes throughout the lifespan are known to influence gut microbiota composition, microbial functional potential, and host-associated metabolic processes. Understanding these age-related variations is important for elucidating their potential physiological implications at different life stages. However, information regarding the gut microbiome and metabolomic characteristics of super-geriatric captive giant pandas (Ailuropoda melanoleuca) remains limited. In this study, fecal samples were collected from adult and super-geriatric captive giant pandas and analyzed using metagenomic sequencing combined with untargeted metabolomics. The gut microbiota of super-geriatric individuals exhibited a marked decrease in Bacillota and an enrichment of Pseudomonadota compared with adult individuals. Functional profiling revealed age-associated shifts in microbial metabolic potential, with a transition from biosynthesis-dominated pathways toward pathways related to substrate degradation and energy utilization. Metabolomic analyses further revealed pronounced metabolic alterations in super-geriatric giant pandas, including elevated levels of unsaturated fatty acids and changes in bile acid–related metabolites. Alterations in gut microbiota composition, particularly the relative enrichment of Pseudomonadota-associated taxa, were associated with inflammation-related metabolic features. Collectively, these findings indicate coordinated changes in gut microbial composition and metabolic profiles during aging. Overall, this study characterizes age-associated alterations in gut microbiota structure and fecal metabolic signatures in super-geriatric captive giant pandas, providing a scientific basis for future studies on microbiota–metabolism interactions and for improving nutritional management and health monitoring strategies in aged individuals of this endangered species. Full article

Nowadays there is a growing interest in alternative technologies to thermal pasteurization (TP) to ensure food microbial safety while minimizing effects on quality attributes like color, enzymatic activity, and bioactive compounds. However, direct comparisons of technologies are often limited to the prospect of microbial reduction levels. In this study, high-pressure processing (HPP), ohmic heating (OH), and TP were comparatively evaluated in red grape juice focusing on several parameters. Process conditions were selected to achieve a comparable 3-log reduction in total aerobic microorganisms as a benchmarking basis. OH and TP resulted in >90% polyphenol oxidase (PPO) inactivation, whereas HPP achieved ~30%. Instrumental color analysis (CIELAB) showed that HPP better preserved juice color, while OH and TP induced significantly darker products compared to fresh juice. Antioxidant capacity (FRAP) and total monomeric anthocyanin content showed modest, non-statistically significant changes across treatments. Conducted under semi-industrial conditions, this assessment highlights technology-specific trade-offs between enzymatic stabilization, color preservation, and bioactive retention. These findings suggest that HPP is superior for preserving heat-sensitive quality attributes, while OH offers an efficient thermal alternative to TP for achieving high enzymatic stability, providing a framework for industrial selection of preservation strategies based on product quality priorities. Full article

Background/Objectives: The effects of thermal drying on the viability of beneficial microorganisms immobilized in biochar, as well as on biochar nutrient retention, remain insufficiently understood. This study aimed to evaluate how drying temperature influences the survival of hyper-ammonia-producing bacteria (HAB) immobilized on pine wood biochar and to assess the impact of subsequent storage on bacterial recovery and nutrient stability. Methods: Biochar was inoculated with HAB and subjected to drying at temperatures ranging from 40 to 60 °C. Following drying, samples were characterized and stored for 30 days. Microbial revival was assessed through reculturing, while changes in surface functional groups were analyzed using FTIR spectroscopy. Nutrient retention, particularly nitrogen content, was also evaluated. Results: Higher drying temperatures resulted in reduced immediate microbial revival during reculturing. However, samples exhibiting limited immediate recovery demonstrated enhanced revival after the 30-day storage period. FTIR analysis revealed that drying temperature modified the availability of surface functional groups associated with microbial attachment and activity. Nutrient analysis indicated only minor reductions in nitrogen retention in biochar dried at temperatures above 55 °C. Conclusions: Drying temperature significantly affects both the short-term survival and post-storage recovery of beneficial microorganisms immobilized in biochar. While elevated temperatures may initially suppress microbial activity, recovery potential during storage remains substantial. Optimizing drying conditions is therefore essential to balance microbial viability with nutrient retention in biochar-based formulations. Full article

Antibiotic-induced dysbiosis has been increasingly implicated in a range of pediatric outcomes, yet the concept remains variably defined and often inconsistently applied. The purpose of this review is to provide an overview and critical evaluation of the available data regarding the effects of early-life exposure to β-lactam antibiotics on the developing microbiome. We conducted a narrative review of experimental and epidemiological studies examining β-lactam exposure during pregnancy, the perinatal period, and early childhood was conducted. β-lactams induce reproducible alterations in microbial composition, diversity, and metabolic function, including decreases in Bifidobacterium and Lactobacillus and a relative increase in Enterobacteriaceae and other facultative anaerobes, especially in early life. Reduced microbial diversity and changed short-chain fatty acid-producing taxa often accompany these compositional changes. However, associations with immune, metabolic, and neurodevelopmental outcomes are heterogeneous and frequently confounded by indication host-related factors. Evidence for causality in humans remains limited despite strong mechanistic support from animal models. Current data support cautious interpretation, even though β-lactam-associated microbiome perturbations may contribute to disease susceptibility during vulnerable developmental windows. While mechanistic and longitudinal evidence continues to develop, antibiotic stewardship focused on appropriate indication and duration is still crucial. Full article