Search Results (124)

To explore an industrial fermentation approach for traditional mung bean sour pulp, this study isolated core microorganisms including lactic acid bacteria and yeasts from naturally fermented samples and constructed a synthetic microbial community. The optimized community consisted of Lactiplantibacillus pentosus, Lactococcus garvieae, and Cyberlindnera jadinii at a ratio of 7:3:0.1 and was used to ferment cooked mung bean pulp with a material-to-water ratio of 1:8 and 1% sucrose addition. Under these conditions, the final product exhibited significantly higher levels of protein (4.55 mg/mL), flavonoids (0.10 mg/mL), polyphenols (0.11 mg/mL), and vitamin C (7.75 μg/mL) than traditionally fermented mung bean sour pulp, along with enhanced antioxidant activity. The analysis of organic acids, free amino acids, and volatile compounds showed that lactic acid was the main acid component, the bitter amino acid content was reduced, the volatile flavor compounds were more abundant, and the level of harmful compound dimethyl sulfide was significantly decreased. These results indicate that fermentation using a synthetic microbial community effectively improved the nutritional quality, flavor, and safety of mung bean sour pulp. Full article

The nuclear receptors pregnane X receptor (PXR), constitutive androstane receptor (CAR), and farnesoid X receptor (FXR) regulate the hepatic metabolism of androstenone, a testicular steroid that accumulates in the fat of intact male pigs and causes boar taint. This study evaluated natural product-derived compounds and conventional agonists targeting these nuclear receptors for their effects on androstenone metabolism in primary hepatocytes from slaughter-weight boars, to assess their potential as treatments for boar taint. Cells were incubated with natural products, conventional agonists, or dimethyl sulfoxide (DMSO; control), then being treated with androstenone. Culture media and cells were analyzed to assess changes in androstenone metabolism and gene expression. UGT1A6 was upregulated by treatments targeting both PXR and CAR and downregulated by FXR agonists. Additionally, PGC1α and NR2F1 were downregulated by compounds targeting PXR/CAR, while FXR and NR0B2 were upregulated and HNF4α downregulated by treatments acting on FXR. The natural products diallyl sulfide (DAS) and (Z)-guggulsterone (GUG) increased overall androstenone metabolism (DAS, GUG) and the production of Phase I androstenol metabolites (DAS), but only in hepatocyte culture replicates that responded positively to these treatments. Although gene expression was similar between positive-response and negative/non-responsive replicates following treatments, negative/non-responsive replicates for several treatments had higher basal expression of UGT2B31, UGT2A1, and SIRT1 and lower basal expression of FXR, PXR, and NR0B1 compared to positive-response replicates. These findings suggest that DAS and GUG may be promising treatments for boar taint, specifically in animals with lower basal rates of androstenone metabolism and higher expression of key nuclear receptors. Full article

Conventional methods for isolating extracellular vesicles (EVs) are often limited by long processing times, a low purity, and a reliance on specialized equipment. To overcome these challenges, we developed the DeSEI (amine-functionalized Diatomaceous earth-based Syringe platform for EV Isolation), a novel platform employing low-cost, amine-functionalized diatomaceous earth (ADe) within a simple syringe–filter system. The capture mechanism leverages the electrostatic interaction between the positively charged ADe and the negatively charged EV surface, enabling a rapid and efficient isolation. The optimized 30 min protocol yields intact EVs with morphology, size, and protein markers comparable to those from ultracentrifugation, ensuring minimal cellular contamination. Notably, DeSEI exhibited a nearly 60-fold higher recovery efficiency of EV-derived miRNA compared to ultracentrifugation. The platform further proved its versatility with a rapid one-step miRNA extraction protocol and a user-friendly cartridge format. The direct miRNA extraction capability is particularly advantageous for a streamlined biomarker analysis, while the cartridge design illustrates a clear pathway toward developing point-of-care diagnostic tools. The DeSEI offers a promising alternative to existing methods for EV-based research by providing a combination of speed, simplicity, and procedural flexibility that does not require specialized equipment. Full article

Background: Halitosis is frequently observed in patients undergoing orthodontic treatment with multibracket appliances, primarily due to volatile sulfur compounds (VSCs) produced by oral anaerobic bacteria. Cetylpyridinium chloride (CPC) is a widely used antimicrobial agent in oral care products and may help alleviate halitosis.This study aimed to evaluate the effects of 0.05% CPC mouthwash on halitosis, oral hygiene indices, and the tongue microbiota in orthodontic patients with elevated VSC levels. Methods: In this randomized, double-blind, placebo-controlled clinical trial, 30 orthodontic patients with elevated VSCs (≥150 ppb) were assigned to a CPC mouthwash group or a placebo group. Participants used the assigned mouthwash three times daily for 1 month. Halitosis was quantitatively assessed by gas chromatography (Oral Chroma™), and oral hygiene parameters including Plaque Index (PI), Gingival Index (GI), Tongue Coating Index (TCI), and unstimulated salivary flow rate were evaluated at baseline and after the intervention. The tongue microbiota was analyzed by 16S rRNA sequencing. Results: The CPC mouthwash group showed significant reductions in total VSCs, hydrogen sulfide, methyl mercaptan, PI, GI, and TCI (p < 0.05), while salivary flow rate and dimethyl sulfide remained unchanged. Microbiome analysis revealed decreases in halitosis-associated genera (Actinomyces, Corynebacterium, Tannerella) and increases in beneficial species such as Streptococcus salivarius. Conclusions: CPC mouthwash (0.05%) effectively reduced halitosis and improved oral hygiene parameters in orthodontic patients, likely through modulation of the tongue microbiota. This mouthwash may serve as a safe and practical adjunct to conventional oral hygiene practices during orthodontic treatment. Full article

This study evaluated the odor mitigation potential of rice husk biochar in a simulated dairy bedded pack over 21 days. Biochar was incorporated into a dairy manure–sawdust mixture at 5% and 10% dry weight. Emissions of key odorous compounds—ammonia (NH₃), sulfur compounds, volatile fatty acids, phenol, p-cresol, and indole—were evaluated. Odor units were assessed to determine perceived odor reduction. Biochar significantly reduced NH₃ and dimethyl sulfide (DMS) emissions: NH₃ by 27% and 43%, and DMS by 53% and 75%, at 5% and 10% application, respectively. The NH₃ reduction was attributed to ammoniacal nitrogen adsorption, while the DMS reduction likely resulted from enhanced air permeability suppressing anaerobic bacterial activity. The 5% biochar treatment, achieving 63% and 70% of the NH₃ and DMS reductions attained by the 10% treatment, respectively, offers a more practical and cost-effective option. Other odorous compounds were not significantly affected. A temporary reduction in odor units was observed on day 7. Rice husk biochar contains 14.5% atomic Si, primarily as silica, which supports structural stability but hinders pore development, reducing adsorption efficiency. These findings demonstrate the importance of biochar’s physicochemical properties in odor mitigation. Future research should evaluate long-term field performance, microbial interactions, and silica modification strategies. Full article

The evaluation of region-specific aroma characteristics in green tea remains critical for quality control. This study systematically analyzed eight Tongcheng Xiaohua tea samples (standard and premium batches) originating from four distinct regions using sensory analysis, electronic nose (E-nose), headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS), and chemometrics. The E-nose results demonstrated that the volatile characteristics of Tongcheng Xiaohua tea exhibit distinct geographical signatures, confirming the regional specificity of its aroma. HS-SPME-GC-MS identified 66 volatile metabolites across samples, with 18 key odorants (OAV > 1) including linalool, geraniol, (Z)-jasmone, and β-ionone driving aroma profiles. The partial least squares–discriminant analysis (PLS-DA) model, combined with variable importance in projection (VIP) scores and OAV, identified seven compounds that effectively differentiate the origins, among which α-pinene and β-cyclocitral emerged as novel markers imparting unique regional characteristics. Further comparative analysis between standard and premium grades revealed 2-methyl butanal, 3-methyl butanal, and dimethyl sulfide as main differential metabolites. Notably, the influence of geographical origin on metabolite profiles was found to be more significant than batch effects. These findings establish a robust analytical framework for origin traceability, quality standardization, and flavor optimization in tea production, providing valuable insights for the tea industry. Full article

The increasing scarcity of traditional nectar sources due to climate change has led beekeepers to explore alternative floral sources. This study investigates the volatile profile, sensory characteristics, and consumer acceptability of monofloral honey derived from Capparis spinosa L., a drought-resistant Mediterranean plant. Honey samples produced by Apis mellifera ssp. sicula on Aeolian Islands (Sicily, Italy) were analyzed. Volatile organic compounds (VOCs) were extracted using headspace solid–phase microextraction (HS-SPME) and identified by gas chromatography–mass spectrometry (GC–MS), revealing 59 compounds, with dimethyl sulfide being the predominant one. Sensory evaluation using quantitative descriptive analysis (QDA) and Time Intensity (TI) analysis identified distinctive descriptors such as sweet-caramel, cabbage/cauliflower, and pungent notes. Statistical analyses confirmed correlations between specific VOCs and sensory perceptions. A consumer acceptability test involving 80 participants showed lower preference scores for caper honey in terms of aroma and overall acceptability compared to commercial multifloral honey, with differences observed across age groups. The unique aromatic profile and consumer feedback suggest that caper honey has strong potential as a niche, high-quality product, particularly within the context of climate-resilient beekeeping, offering valuable opportunities for innovation and diversification in sustainable apiculture. Full article

WO₃/V₂O₅/TiO₂ (W_xV₅TiO₂) catalysts were prepared via a wet incipient method with a V/Ti mass ratio = 0.05 and a W/Ti mass ratio varying from 0 to 0.10. The catalysts were calcined in air for 24 h at temperatures of 400 °C, 500 °C, 550 °C, and 600 °C. The presence of WO₃ on W_xV₅TiO₂ catalysts inhibits morphological and crystal structure transformations as the calcination temperature increases from 400 °C to 600 °C. The results of this study give evidence that the active component of the catalyst is V on anatase TiO₂. Therefore, the incorporation of WO₃ onto an anatase TiO₂ support widens the temperature range at which the WO₃/V₂O₅/TiO₂ catalyst maintains the anatase crystal structure and, hence, the performance of the catalyst. The catalytic oxidation of dimethyl sulfide (DMS) was used as a probe reaction to evaluate catalytic activity. The results indicate that WO₃/V₂O₅/TiO₂ catalysts are capable of effectively oxidizing DMS at relatively low reaction temperatures (250 °C), even under conditions of an elevated DMS concentration in air (1.6 vol%). Full article

Numerical simulation studies of the dispersion of dimethyl sulfide (DMS) in the air have increased over the last two decades in parallel with the interest in understanding its role as a precursor of non-sea salt aerosols in the lower to middle levels of the troposphere. Here, we review recent numerical modeling studies that have included DMS emissions, their atmospheric oxidation mechanism, and their subsequent impacts on air quality at regional and global scales. In addition, we discuss the available methods for estimating sea–air DMS fluxes, including parameterizations and climatological datasets, as well as their integration into air quality models. At the regional level, modeling studies focus on the Northern Hemisphere, presenting a large gap in Antarctica, Africa, and the Atlantic coast of South America, whereas at the global scale, modeling studies tend to focus more on polar regions, especially the Arctic. Future studies must consider updated climatologies and parameterizations for more realistic results and the reduction in biases in numerical simulations analysis. Full article

Background: Fusobacterium nucleatum is a pathobiont that plays a dual role as both a commensal and a pathogen. The oral cavity typically harbors this anaerobic, Gram-negative bacterium. At the same time, it is closely linked to colorectal cancer due to its potential involvement in tumor progression and resistance to chemotherapy. The mechanism by which it transforms from a commensal to a pathogen remains unknown. For this reason, we investigated the role of oxidative status as an initiatory factor in changing the bacterium’s pathogenicity profile. Methods: A clinical strain of F. nucleatum subsp. animalis biofilm was exposed to different oxidative stress levels through varying subinhibitory amounts of H₂O₂. Subsequently, we investigated the bacterium’s behavior in vitro by infecting the HT-29 cell line. We evaluated bacterial colonization, volatile sulfur compounds production, and the infected cell’s oxidative status by analyzing HMOX1, pri-miRNA 155, and 146a gene expression. Results: The bacterial colonization rate, dimethyl sulfide production, and pri-miRNA 155 levels all increased when stressed bacteria were used, suggesting a predominant pathogenic function of these strains. Conclusions: The response of F. nucleatum to different oxidative conditions could potentially explain the increase in its pathogenic traits and the existence of environmental factors that may trigger the bacterium’s pathogenicity and virulence. Full article

Parasitic nematodes, particularly those in the Rhabditidae family, are vital components of belowground ecosystems, contributing to pest regulation and sustainable agriculture. This study investigated the chemotactic responses of three nematode species—Phasmarhabditis papillosa, Oscheius myriophilus, and O. onirici—to volatile organic compounds (VOCs) emitted by Brassica nigra roots under herbivory by Delia radicum larvae. Using a chemotaxis assay, the effects of five VOCs (dimethyl sulfide, dimethyl disulfide, allyl isothiocyanate, phenylethyl isothiocyanate, and benzonitrile) were tested at two concentrations (pure and 0.03 ppm) and two temperatures (18 °C and 22 °C). The results revealed that VOCs and temperature significantly influenced nematode responses, while nematode species and VOC concentration showed limited effects. Benzonitrile consistently demonstrated strong chemoattractant properties, particularly for O. myriophilus and O. onirici. Conversely, allyl isothiocyanate exhibited potent nematicidal effects, inhibiting motility and causing mortality. Dimethyl disulfide and dimethyl sulfide elicited moderate to strong attractant responses, with species- and temperature-dependent variations. Significant interactions between VOCs, temperature, and nematode species highlighted the complexity of these ecological interactions. These findings emphasize the ecological roles of VOCs in mediating nematode behavior and their potential applications in sustainable pest management. Benzonitrile emerged as a promising candidate for nematode-based biocontrol strategies, while allyl isothiocyanate showed potential as a direct nematicidal agent. The study underscores the importance of integrating chemical cues into pest management systems to enhance agricultural sustainability and reduce reliance on chemical pesticides. Full article

Volatile chemicals containing nitrogen and sulfur as key odors in dry-cured meat products have extremely low odor thresholds. These compounds play an important part in the overall uniqueness and characteristic flavor of dry-cured meat products, contributing to savory and toasted aroma sensations, respectively. In this review, we define the different volatiles and aroma compounds related to the flavor of dry-cured meat products. Moreover, the main differences regarding volatiles, aromas, and flavor profiles from non-fermented and fermented dry-cured meat products are summarized. Comparisons using the same volatile extraction techniques revealed that dry loins contained the most sulfur- and nitrogen-containing compounds, while complex flavor and aroma compounds in fermented sausages were greatly impacted by the fermentation process. The screening and quantification of savory and toasted odors showed that methionol, dimethyl sulfide, and 2-methyl-3-(methylthio)furan were mainly reported in non-fermented products, whereas pyrazines were mainly detected in fermented meat products. Finally, the different mechanisms in the generation of savory and toasted aromas, including chemical reactions and biochemical reactions by microorganisms (bacteria, yeast, and molds), are discussed. These discussions will help to better understand the complex flavor of dry-cured meat products. Full article

The unambiguous detection of biosignatures in exoplanet atmospheres is a primary objective for astrobiologists and exoplanet astronomers. The primary methodology is the observation of combinations of gases considered unlikely to coexist in an atmosphere or individual gases considered to be highly biogenic. Earth-like examples of the former include CH₄ and O₃, and the latter includes dimethyl sulfide (DMS). To improve the plausibility of the detection of life, I argue that the isotope ratios of key atmospheric species are needed. The C isotope ratios of CO₂ and CH₄ are especially valuable. On Earth, thermogenesis and volcanism result in a substantial difference in δ¹³C between atmospheric CH₄ and CO₂ of ~−25‰. This difference could have changed significantly, perhaps as large as −95‰ after the evolution of hydrogenotrophic methanogens. In contrast, nitrogen fixation by nitrogenase results in a relatively small difference in δ¹⁵N between N₂ and NH₃. Isotopic biosignatures on ancient Earth and rocky exoplanets likely coexist with much larger photochemical signatures. Extreme δ¹⁵N enrichment in HCN may be due to photochemical self-shielding in N₂, a purely abiotic process. Spin-forbidden photolysis of CO₂ produces CO with δ¹³C < −200‰, as has been observed in the Venus mesosphere. Self-shielding in SO₂ may generate detectable ³⁴S enrichment in SO in atmospheres similar to that of WASP-39b. Sufficiently precise isotope ratio measurements of these and related gases in terrestrial-type exoplanet atmospheres will require instruments with significantly higher spectral resolutions and light-collecting areas than those currently available. Full article

This study investigates the effects of different washing methods and intake concentrations on the removal efficiency of odor gases and particulate matter. Odor concentration (OU value) was used as the evaluation criterion, with three concentration gradients established: high (1000–1100 OU), medium (500–600 OU), and low (200–300 OU). The experiment employed water washing, acidic washing (pH = 4), and alkaline washing (pH = 10) to analyze the removal rates across nine treatments. Results indicated that the removal rate of ammonia significantly increased with higher intake concentrations (p < 0.01), while intake concentration had no significant effect on the removal rates of hydrogen sulfide and volatile organic compounds (VOCs). Acidic washing achieved the highest ammonia removal rate (72.68%) (p < 0.01), whereas alkaline washing showed the highest hydrogen sulfide removal rate (64.87%) (p < 0.01). For VOCs, the removal rates for water washing, acidic washing, and alkaline washing were 50.35%, 59.70%, and 61.56%, respectively, which were significantly lower than those for acidic and alkaline washing (p < 0.01). Alkaline washing demonstrated a significantly higher removal rate for methyl mercaptan compared to water washing and acidic washing (p < 0.01), and also for dimethyl sulfide compared to acidic washing (p < 0.05). Trimethylamine and carbon disulfide removal rates by acidic and alkaline washing were significantly higher than those by water washing (p < 0.01). There was no significant difference in styrene removal rates among different washing methods (p > 0.05), although acidic washing showed the best performance. Neither washing method nor intake concentration significantly affected particulate matter removal. It is recommended to combine acidic and alkaline washing for optimal deodorization. Full article

Dimethyl sulfide (DMS), a low-boiling compound generated during barley germination and wort boiling from the conversion of its main precursor S-methylmethionine (SMM), a functional biomolecule, is detrimental to beer flavor. Vigorous and prolonged boiling, a time-consuming and energy-intensive process, is required to decrease the content of SMM and remove free DMS. The standard model, further validated in this study, assumed wort temperature and pH as the limiting factors of the SMM conversion reaction. This study aimed to assess the specific effect of hydrodynamic cavitation (HC) on the SMM conversion rate in pilot-scale experiments of brewer’s wort boiling. For the first time, the SMM conversion rate was shown to be significantly affected by HC processes. The SMM half-life was reduced by up to 70% and showed remarkable sensitivity to HC regimes. The intensification of the SMM conversion reaction could be attributed to the HC-based generation of hydroxyl radicals. Other wort processes unfolded in compliance with standard specifications, such as the removal of free DMS, the isomerization of hop alpha-acids, and the change in wort color. In conclusion, evidence supported HC for a substantial saving in process time and energy consumption in the brewer’s wort boiling step. Full article