Levels Of Volatile Sulfur Compounds Research Articles

Clinical and measurement variables affecting halitosis intensity following cysteine challenge test

The cysteine challenge test is a reliable and efficient method for halitosis diagnosis and assessing treatment effectiveness by measuring the capacity to produce hydrogen sulfide. However, several aspects related to the test including evaluation timing and total duration following cysteine loading has not been investigated in-depth and a standardized protocol is yet to be established. This observational study compared concentrations of volatile sulfur compounds (VSCs) following cysteine challenge at various time points based on different measurement tools to investigate clinical factors influencing the results. Cysteine challenge (rinsing for 30 s with 5 mL of 6 mM L-cysteine solution) was applied in 100 healthy subjects. VSC concentration of oral cavity gas was analyzed with standard and portable gas chromatography (GC) at 5 time points (before, immediately, 10, 20, and 30 min after cysteine challenge). The Community Periodontal Index of Treatment Needs (CPITN), Winkel’s Tongue Coating Index, and salivary flow rate were assessed. VSC levels significantly increased immediately after cysteine challenge (p < 0.001 for hydrogen sulfide, p < 0.001 with standard GC and p < 0.05 with portable GC for methyl mercaptan). Levels significantly decreased at 10 min after cysteine challenge except for methyl mercaptan measured with standard GC (p < 0.001). Subjects still showing VSCs 20 min after cysteine challenge was less than 15% of those initially positive. The amount of tongue coating showed significant association with methyl mercaptan levels immediately after (β = 0.202, p = 0.049) and 10 min following (β = 0.207, p = 0.045) cysteine challenge and CPITN showed acceptable discriminative power for persistent detection of methyl mercaptan (cut-off = 1.5, AUC = 0.668). Cysteine challenge may enhance the possibility of detecting VSCs during halitosis diagnosis. Standardized test protocols should address measurement timing, tools used, and tongue coating levels as clinical factors influencing VSC detection.

The effect of salivary flow rate on the risk of bad breath (halitosis) during the Ramadan fasting

Background: Ramadan fasting is a significant religious practice for Muslims, characterized by abstinence from food and drink from dawn to sunset. This fasting routine induces physiological changes, including reduced salivary flow and altered salivary composition, which may compromise oral health. These changes increase the risk of halitosis and other oral issues due to decreased protective functions of saliva and the proliferation of volatile sulfur compound (VSC)-producing bacteria. Objective: To review the relationship between reduced salivary flow during Ramadan fasting and the risk of halitosis, as well as to identify effective preventive measures to mitigate these effects. Method: A literature review was conducted using secondary data from databases such as PubMed, ScienceDirect, and Google Scholar. The inclusion criteria focused on studies published between 2017 and 2025 that explored salivary flow rate, halitosis, and the effects of Ramadan fasting. Results: The review highlighted a significant reduction in salivary flow, with rates decreasing up to 50% during fasting. This reduction leads to an increase in VSC levels, which are the primary contributors to halitosis. Additionally, fasting affects the composition of saliva, including lower levels of phosphate and calcium, further exacerbating oral health issues. Conclusion: Ramadan fasting significantly influences oral cavity health by reducing salivary flow and altering its composition, increasing the risk of halitosis and other dental issues. Halitosis is primarily caused by volatile sulfur compounds produced by gram-negative anaerobic bacteria thriving in reduced saliva conditions.

Efficacy of Toothpaste Containing Polylysine and Funme Peptide on Oral Microbiome and Oral Health.

To evaluate the effect of the toothpaste containing ε-poly-L-lysine (ε-PL) and funme peptide (FP) as key components on oral microbial composition and oral health. An oral microbiome study was initially carried out to analyze the variation in the oral microbiota before and after use of antimicrobial peptide (AMP) toothpaste. Subsequently, a clinical trial was independently performed to assess the efficacy of AMP toothpaste by measuring the dental plaque index (PLI), volatile sulfur compounds (VSCs) levels, modified bleeding index (mBI), and bleeding on probing rate (BOP%). The application of AMP toothpaste increased the α diversity and modified β diversity of oral microbiome across 3 oral niches. AMP toothpaste increased the relative abundance of the commensal oral microbes, and attenuated the abundance of pathogenic bacteria in gingivitis patients to normal levels. The clinical trial showed 44.33% and 12.29% reductions of PLI scores in the test and control groups, respectively, and the test group exhibited a more pronounced decrease in VSC levels. The test group recorded significant reductions in mBI and BOP% by 39.09% and 24.59%, respectively, exceeding the control group's reductions of 4.63% and -0.97% (P < .05). The formulation of toothpaste with ε-PL and FP recalibrated the oral microbiome's diversity and abundance, and mitigated common oral health issues such as plaque, halitosis, and gingivitis while maintaining well safety. Oral care products containing ε-PL and FP can be used as a new treatment for improving oral microbiota and oral diseases.

Volatile sulfur compounds and salivary parameters in patients undergoing head and neck cancer treatment: A preliminary study

BackgroundTreatment for head and neck squamous cell carcinoma (HNSCC) is often associated with various adverse effects, including changes in salivary parameters and complaints of halitosis. This study aimed to investigate changes in volatile sulfur compound (VSC) levels and salivary parameters in patients undergoing treatment for HNSCC. MethodsThis prospective longitudinal study was conducted at a Brazilian oncology center, where a convenience sample of 24 HNSCC patients undergoing radiotherapy or chemoradiotherapy were evaluated for VSC levels, salivary flow, pH, viscosity, dry mouth, and tongue coating. Assessments were performed at the beginning and end of antineoplastic therapy. VSC levels were measured using an Oral Chroma™ gas chromatograph. Data were analyzed descriptively and analytically. ResultsNo significant changes were found in overall VSC levels. However, a statistically significant reduction in salivary flow (p < 0.001) and pH (p = 0.017) and an increase in salivary viscosity (p = 0.037) were noted post-treatment. Patients who reported halitosis after treatment exhibited significantly higher hydrogen sulfide levels (p = 0.045). Tongue coating and VSC levels showed no significant changes. ConclusionTreatment for HNSCC results in reduced salivary flow, altered pH, and increased salivary viscosity. Although self-reported halitosis correlates with elevated hydrogen sulfide levels post-treatment, no significant changes in overall VSC concentrations were observed.

Halitosis in oral lichen planus patients

To investigate the halitosis level in oral lichen planus (OLP) patients and OLP-free participants. This cross-sectional study recruited 70 participants at the New Zealand's National Centre for Dentistry. Halitosis was determined using the objective measurements (parts per billion (ppb) volatile sulphur compounds (VSCs) in the exhaled air) and subjective measurement (self-reported halitosis questionnaire). The VSCs values of OLP participants (mean ± SD: 144.64 ± 23.85 ppb) were significantly greater than that in the OLP-free participants (105.52 ± 22.31ppb) (mean difference: 39.12 ppb;p< 0.05; 95% CI: 27.95, 50.29). The VSCs value of hyperplastic (mean difference: 34.11; 95% CI: 20.07, 48.15;p< 0.05) and erosive/ulcerative (mean difference: 57.47; 95% CI: 34.19, 80.76;p< 0.05) OLP participants were statistically greater than that of OLP-free participants. No statistical significance was found between hyperplastic and erosive/ulcerative OLP (p> 0.05). 'Type (OLP-free/OLP)' has a significant effect on the dependent variable VSCs. 78.6% of OLP and 90.5% of OLP-free brushed their teeth at least twice daily, with a statistically significant observation (Mean square: 1.61; F: 13.13;p< 0.05). The levels of VSCs were greater in participants with hyperplastic and erosive/ulcerative OLP than that in the OLP-free participants.

Development and validation of the Thai Halitosis Associated Life-Quality Test (T-HALT): an evaluation of psychometric properties.

Halitosis appears to have significant impacts on quality of life, necessitating reliable assessment tools. The Halitosis Associated Life-Quality Test (HALT) has been validated in various populations, but not among Thai people. While HALT provides a valuable foundation, there is a need for a culturally adapted and expanded instrument for the Thai context. Consequently, this study aimed to develop and validate a comprehensive questionnaire for assessing halitosis-related quality of life in Thai populations, incorporating a Thai version of HALT (T-HALT) as a core component. This cross-sectional study involved 200 dental patients at Mahidol University. The original HALT was translated into Thai using forward-backward translation. Cultural adaptation and psychometric properties of T-HALT were evaluated through multiple approaches. Content validity was ensured through expert reviews, while face validity was assessed by patient feedback. Reliability was examined via test-retest and internal consistency measures. Criterion and discriminant validity was evaluated by correlating T-HALT scores with self-perceived halitosis and volatile sulfur compound (VSC) measurements, respectively. VSCs were quantified using the OralChroma™ device, which analyzes breath samples collected directly from patients' mouths. Construct validity was assessed through exploratory (EFA) and confirmatory factor analysis (CFA), providing insights into the questionnaire's underlying structure. T-HALT demonstrated excellent internal consistency (Cronbach's alphas = 0.940-0.943) and test-retest reliability (ICC = 0.886). Criterion validity was supported by a significant correlation between T-HALT scores and self-perceived halitosis (r = 0.503, P < 0.001). Discriminant validity was confirmed by the absence of a significant correlation between T-HALT scores and VSC levels (r = 0.071, P = 0.32). EFA revealed a four-factor structure, which was subsequently confirmed by CFA. However, Items 1 and 7 were excluded due to poor standardized factor loadings. T-HALT demonstrates good reliability and validity for assessing halitosis-related quality of life in Thai populations. It performs well as a unidimensional measure, but its multidimensional application requires modifications. Future research should validate a modified version excluding Items 1 and 7 across diverse Thai populations, potentially enhancing its cultural specificity.

A retrospective analysis of patients suffering from halitosis over a 17-year period.

Halitosis is a socially avoided topic with an increasing worldwide prevalence. This study aimed to investigate the correlation between the different forms of halitosis and factors such as: gender, smoking, stress, and oral hygiene. We analysed data from patients registered at the Center of Salivary Diagnostics, Hyposalivation and Halitosis at the University Center for Dental Medicine Basel over a 17-year period, using both subjective and objective approaches to determine the presence of halitosis. The data was statistically analysed using chi-squared and Wilcoxon rank-sum tests. Although halitosis is of multifactorial origin, an oral cause was found in 3 out of 4 patients. Men showed higher values of volatile sulfur compounds (VSC) (p = 0.002) indicative of halitosis than women, while women displayed better oral hygiene (p < 0.001), yet were twice as likely to suffer from halitophobia than males. Patients with higher tongue coating scores (p < 0.001) and periodontitis (p < 0.001) had higher levels of VSC, contributing to bad breath, whereas patients with symptoms such as stress (p = 0.81) or smoking (p = 0.28) did not reveal significantly altered measurements. This study sheds light on the complex and multifactorial nature of halitosis over a long period of time. It further underlines the importance of individualized treatment strategies, given halitosis' multifactorial nature, in order to contribute to the patients' treatment needs.

The Influence of Probiotics in Halitosis and Cariogenic Bacteria: A Systematic Review and Meta-Analysis

Background: The aim of this systematic review was to evaluate the therapeutic potential of probiotics in patients with halitosis and to assess whether probiotics can also be implemented as a preventative tool in oral health. Secondary objectives included the effect of probiotics on oral-health-related quality of life, as well as their safety. Materials and methods: An electronic literature search in Medline (PubMed), Scopus, Web of Science, and the Cochrane library was carried out for the identification and selection of relevant randomized controlled trials. Eligibility was based on inclusion criteria, which included RCTs published after 2013, and the outcome variables were volatile sulfur compound (VSC) levels, organoleptic scores, plaque, or saliva samples to assess cariogenic bacteria counts and/or pH levels. Results: Out of 192 identified records, 16 randomized controlled trials were included. Ten of those studied the effects of probiotics on halitosis and the other six analyzed the effect of probiotics on oral health parameters, such as cariogenic bacteria counts, pH levels, and salivary flow and quality. A total of 921 patients were evaluated. The risk of bias was assessed using the Cochrane risk-of-bias assessment tool version 2. Conclusions: Probiotics exhibit the potential for oral health management by reducing VSC levels, improving saliva quality, and enhancing oral-health-related quality of life. Combining probiotics with tongue scraping may sustain VSC reduction, while symbiotics show potential in reducing tongue coating. However, different bacterial strains have been used in the included studies; hence, the conclusions cannot be generalized, being one of the main limitations of this review. Future research should explore the probiotics’ potential to persist in the oral cavity post-treatment and employ standardized methodologies for conclusive efficacy assessment.

Lavandula angustifolia Essential Oil Inhibits the Ability of Fusobacterium nucleatum to Produce Volatile Sulfide Compounds, a Key Components in Oral Malodor.

Oral malodor still constitutes a major challenge worldwide. A strong effort is invested in eliminating volatile sulfur compound-producing oral bacteria through organic natural products such as essential oils. Fusobacterium nucleatum is a known volatile sulfur compound-producing bacteria that inspires oral malodor. The aim of the present study was to test the effect of lavender essential oil on the bacterium's ability to produce volatile sulfide compounds, the principal components of oral malodor. Lavender (Lavandula angustifolia) essential oil was extracted by hydrodistillation and analyzed using GC-MS. The minimal inhibitory concentration (MIC) of lavender essential oil on Fusobacterium nucleatum was determined in a previous trial. Fusobacterium nucleatum was incubated anaerobically in the presence of sub-MIC, MIC, and above MIC concentrations of lavender essential oil, as well as saline and chlorhexidine as negative and positive controls, respectively. Following incubation, volatile sulfur compound levels were measured using GC (Oralchroma), and bacterial cell membrane damage was studied using fluorescence microscopy. Chemical analysis of lavender essential oil yielded five main components, with camphor being the most abundant, accounting for nearly one-third of the total lavender essential oil volume. The MIC (4 µL/mL) of lavender essential oil reduced volatile sulfur compound secretion at a statistically significant level compared to the control (saline). Furthermore, the level of volatile sulfur compound production attributed to 1 MIC of lavender essential oil was in the range of the positive control chlorhexidine with no significant difference. When examining bacterial membrane damage, 2 MIC of lavender essential oil (i.e., 8 µL/mL) demonstrated the same, showing antibacterial membrane damage values comparative to chlorhexidine. Since lavender essential oil was found to be highly effective in hindering volatile sulfur compound production by Fusobacterium nucleatum through the induction of bacterial cell membrane damage, the results suggest that lavender essential oil may be a suitable alternative to conventional chemical-based anti-malodor agents.

Halitosis in young patients with chronic kidney disease: findings from a randomized controlled trial

BackgroundChronic kidney disease (CKD) directly affects oral health. Yet data about halitosis in young CKD patients and the impact of dental prophylaxis is limited. Therefore, as part of this randomized clinical trial, halitosis in young CKD patients undergoing intensive or standard oral preventive procedures was to be explored.MethodsThree volatile sulfur compounds (hydrogen sulfide, methyl mercaptan and dimethyl sulfide) were measured in 30 young patients with CKD (mean age 14.2 years; 16 males, 14 females). Breath samples were taken after 3 and 6 months and analyzed with selective gas chromatography (OralChroma). Tongue coating (Winkel Index) and clinical indices to determine local inflammation or oral hygiene (Papillary Bleeding Index and Quigley-Hein Index) were assessed. Within an extended anamnesis, patients and their mothers and nurses were questioned about the perceived halitosis. Corresponding quotes were noted verbatim. Patients were randomized to either intensive need-related oral health care measures (oral preventative program, OPP) or a one-stage standard prevention (treatment as usual, TAU).ResultsWhile there were no differences in volatile sulfur compound levels between TAU and OPP at the three time points of measurements (p > 0.05), there was a tendency towards a reduction in dimethyl sulfide and hydrogen sulfide of affected patients within the OPP group over time. Looking at potential differences between both groups with regard to tongue coating, significant differences were observed between baseline and 3 months after study start in the OPP group, and between baseline and 6 months after study start in the TAU group (p < 0.05). The burden of halitosis was frequently reported by patients’ mothers and nurses.ConclusionsYoung CKD patients regularly suffered from halitosis and dimethyl sulfide was its main source. Preventive measures mainly resulted in a reduction of tongue coating. Trial registration: The German Clinical Trial Register (# DRKS00010580).

Efficacy of a mouthwash containing ε-poly-L-lysine, funme peptides and domiphen in reducing halitosis and supragingival plaque: a randomized clinical trial

ObjectiveTo evaluate the antibacterial effectiveness of a combination of ε-poly-L-lysine (ε-PL), funme peptide (FP) as well as domiphen against oral pathogens, and assess the efficacy of a BOP® mouthwash supplemented with this combination in reducing halitosis and supragingival plaque in a clinical trial.Materials and methodsThe minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the compound against Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans were determined by the gradient dilution method. Subsequently, the CCK-8 assay was used to detect the toxicity of mouthwash on human gingival fibroblastst, and the effectiveness in reducing halitosis and supragingival plaque of the mouthwash supplemented with the combination was analyzed by a randomized, double-blind, parallel-controlled clinical trial.ResultsThe combination exhibited significant inhibitory effects on tested oral pathogens with the MIC < 1.56% (v/v) and the MBC < 3.13% (v/v), and the mouthwash containing this combination did not inhibit the viability of human gingival fibroblasts at the test concentrations. The clinical trial showed that the test group displayed notably lower volatile sulfur compounds (VSCs) at 0, 10, 24 h, and 7 d post-mouthwash (P < 0.05), compared with the baseline. After 7 days, the VSC levels of the and control groups were reduced by 50.27% and 32.12%, respectively, and notably cutting severe halitosis by 57.03% in the test group. Additionally, the Plaque Index (PLI) of the test and control group decreased by 54.55% and 8.38%, respectively, and there was a significant difference in PLI between the two groups after 7 days (P < 0.01).ConclusionsThe combination of ε-PL, FP and domiphen demonstrated potent inhibitory and bactericidal effects against the tested oral pathogens, and the newly formulated mouthwash added with the combination exhibited anti-dental plaque and anti-halitosis properties in a clinical trial and was safe.Trial registrationThe randomized controlled clinical trial was registered on Chinese Clinical Trial Registry (No. ChiCTR2300073816, Date: 21/07/2023).

Effect of sleeve gastrectomy on the levels of oral volatile sulfur compounds and halitosis-related bacteria

BackgroundThe association between sleeve gastrectomy and halitosis remains relatively unknown. Therefore, this study aimed to evaluate the effect of sleeve gastrectomy on halitosis and the oral bacterial species associated with halitosis in patients with obesity. MethodsThis was a prospective longitudinal cohort study that examined patients before and after sleeve gastrectomy and followed the patients at three time intervals (1, 3, and 6 months) after sleeve gastrectomy. Clinical periodontal measurements (plaque index [PI], gingival index [GI], and probing depth [PD]) were obtained. In addition, plaque samples were collected for quantification of the periodontopathogenic bacteria: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum using real-time quantitative polymerase chain reaction (qPCR). In addition, breath samples were collected to analyze the concentration of volatile sulfur compounds (VSCs), namely hydrogen sulfide (H2S), methyl mercaptan (CH3SH), and dimethyl sulfide (CH3SCH3), via portable gas chromatography (Oral Chroma™). ResultsOf the 43 patients initially included, 39 completed the study, with a mean age of 32.2 ± 10.4 years. For PI and GI repeated measurements one way analysis of variance showed a significant increase (p-value < 0.001 for both) one month after surgery, with mean values of 1.3 and 1.59, respectively, compared to the baseline. During the same period, the number of P. gingivalis increased, with a p-value = 0.04. Similarly, the levels of hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) increased significantly in the first month after surgery (p-value = 0.02 and 0.01, respectively). ConclusionThis study demonstrated that sleeve gastrectomy may lead to increased halitosis one month post-surgery, attributed to elevated and P. gingivalis counts, contributing to the development of gingivitis in obese patients who underwent sleeve gastrectomy. This emphasizes the importance of including oral health professionals in the multidisciplinary team for the management of patients undergoing bariatric surgery

Preliminary investigation of a combined herbal extract of Aruncus dioicus, Cirsium nipponicum, and Ocimum basilicum for halitosis.

Halitosis, the unpleasant odor in the oral cavity, has garnered increased attention and concern due to the growing significance of social interaction. SGE-107, a blend of 3 botanical drugs-Korean goat's beard, Cirsium tanakae, and Basil-with caffeic acid as its indicator component. This study aims to investigate the efficacy of SGE-107 in treating halitosis in patients with mild gastrointestinal symptoms. We enrolled 25 participants with oral malodor and dyspeptic symptoms. We assessed the severity of halitosis using the visual analog scale. Throughout a 4-week period of administering SGE-107, we evaluated both objective and subjective parameters, including the halitosis-associated life-quality test, the Korean gastrointestinal symptom rating scale, levels of volatile sulfur compounds, salivary flow rate, oral moisture, tongue index, Winkel tongue coating index, and tongue temperature. After the intervention period, both the visual analog scale (5.88 ± 1.03 vs 2.38 ± 0.93, P < .001) and the scores of the halitosis-associated life-quality test (31.21 ± 11.78 vs 13.83 ± 6.38, P < .001) showed significant reductions. The proportion of participants with abnormal levels of methyl mercaptan (a volatile sulfur compound) also significantly decreased (17, 70.8% vs 9, 37.5%, P = .039). Furthermore, there were significant improvements in reflux, constipation, diarrhea, and the total scores on the Korean gastrointestinal symptom rating scale. Throughout the study period, only 2 participants experienced mild adverse events. SGE-107 appears to be a safe and effective treatment for halitosis-associated with gastrointestinal symptoms; nevertheless, the limited sample size necessitates further large-scale randomized, controlled studies to confirm our findings.

Effects of Lactiplantibacillus plantarum CCFM1214 and Ligilactobacillus salivarius CCFM1215 on halitosis: a double-blind, randomized controlled trial.

The purpose of this study was to evaluate the effects of known probiotic species Lactiplantibacillus plantarum CCFM1214 and Ligilactobacillus salivarius CCFM1215 on halitosis, the oral status, and the oral microbiome. In a double-blind, randomized controlled trial that lasted for five weeks, 43 participants were divided into an oral probiotics group and a control group and given probiotics or control powder for the first four weeks, with the fifth week being the discontinuation period. 33 participants (probiotics group = 21, control group = 12) completed the entire experiment in the end. Oral samples were taken as part of oral health examinations during the baseline period (day 0) and four weeks after (day 28). The nucleotide sequence of the V3-V4 region of 16S rRNA was determined to examine the impact of intervention and time on the oral microbiome. The effects of L. plantarum CCFM1214 and L. salivarius CCFM1215 on the number of Fusobacterium nucleatum in gingival crevicular fluid (GCF) samples of participants were detected by quantitative PCR. After the intervention, L. plantarum CCFM1214 and L. salivarius CCFM1215 significantly reduced the levels of volatile sulfur compounds (VSCs) and the quantity of F. nucleatum in GCF samples, where the average DNA copy number per ng (log) of F. nucleatum decreased from 7.12 ± 0.04 to 6.01 ± 0.09. The β diversity of the probiotics group, on the whole, tended to be more concentrated and stable after the intervention. In addition, after probiotic intervention, the abundance of Lactobacillus and Bifidobacterium increased, while the abundance of Fusobacterium, Acinetobacter, Porphyromonas, and Aggregatibacter decreased significantly. In general, L. plantarum CCFM1214 and L. salivarius CCFM1215 can alleviate halitosis and considerably lower the value of VSCs and improve the oral microbiota in participants with halitosis.

Phyllanthus emblica fruit extract alleviates halitosis and reduces the inflammatory response to oral bacteria.

To assess the efficacy of Phyllanthus emblica extract in alleviating halitosis and reducing the inflammatory response to halitosis-related bacteria. This investigation, using Phyllanthus emblica fruit extract (PE), involved four aspects. First, we evaluated the effect on growth and aggregation of halitosis-related bacteria, including Fusobacterium nucleatum, Porphyromonas gingivalis, and Solobacterium moorei, using a microdilution assay and scanning electron microscopy. Second, volatile sulfur compound (VSC) levels were measured on individuals with halitosis in randomized short-term (26 participants) and double-blind randomized long-term trials (18 participants in each group) after rinsing with PE for 3, 6, and 12 h, and 28 days. Third, we analyzed pro-inflammatory cytokine expression in TR146 cells using quantitative real-time PCR and enzyme-linked immunosorbent assays. Lastly, we assessed pro-inflammatory cytokine secretion and Toll-like receptor (TLR) 2 mRNA expression via the same experimental methods in a three-dimensional oral mucosal epithelial model (3D OMEM). PE extract dose-dependently inhibited the growth of F. nucleatum (50% inhibition concentration [IC50]=0.079%), P. gingivalis (IC50=0.65%), and S. moorei (IC50=0.07%) and effectively prevented bacterial aggregation. Furthermore, VSC contents decreased significantly at 3, 6, and 12 h after rinsing with 5% PE compared with those in the control. Long-term use of mouthwash containing 5% PE for 28 days led to a significant decrease in VSC contents. PE attenuated the F. nucleatum- or P. gingivalis-stimulated mRNA expression and protein release of interleukin (IL)-6 and IL-8 in TR146 cells. It also suppressed IL-8 and prostaglandin E2 secretion and TLR2 mRNA expression in F. nucleatum-induced OMEMs. Our findings support the use of PE in oral care products to alleviate halitosis and it may reduce inflammation.

Therapeutic effect of aged garlic extract on gingivitis in dogs.

Periodontal disease is one of the most common dental health problems in dogs. Clinical studies in humans have shown that aged garlic extract (AGE), which contains stable and water-soluble sulfur-containing bioactive compounds, improves the symptoms of periodontal diseases. Our previous study demonstrated that oral administration of AGE in healthy Beagle dogs at 90 mg/kg/day for 12 weeks had no adverse effects such as hemolytic anemia, which is well known to occur as a result of ingestion of Allium species, including onions and garlic, in dogs. However, the therapeutic potential of AGE in canine periodontal disease remains unclear. Accordingly, we investigated the therapeutic effects of AGE in Beagle dogs with mild gingivitis. Feeding 18 mg/kg/day of AGE for 8 weeks resulted in the improvement of gingival index score, level of volatile sulfur compounds in exhaled air, and enzyme activity of periodontal pathogens without any adverse effects on clinical signs and hematological and serum biochemical parameters. Moreover, AGE increased the concentration of salivary cathelicidin, an antimicrobial peptide that contributes to the oral innate immune response. These results suggest that AGE could be a potential therapeutic agent for canine gingivitis.

Antimicrobial Effects of Edible Mixed Herbal Extracts on Oral Microorganisms: An In Vitro Study.

Background and Objectives: The oral cavity is inhabited by pathogenic bacteria, whose growth can be inhibited by synthetic oral drugs, including antibiotics and other chemical compounds. Natural antimicrobial substances that elicit fewer negative side effects may serve as alternatives to synthetic agents for long-term use. Thus, the aim of this study was to evaluate the effects of edible mixed herbal extracts on the growth of oral pathogenic bacteria. Materials and Methods: The yield of each herbal extract was as follows: 5% Schizonepeta tenuifolia Briq (STB), 10.94% Mentha piperascens (MP), 5.47% Acanthopanax sessiliflorus Seem (AS), and 10.66% Glycyrrhiza uralensis (GU). The herbal extracts used included 0.5 mg/mL STB, 1.5 mg/mL MP, 1.5 mg/mL AS, and 2.0 mg/mL GU. Antimicrobial tests, morphological analyses (using scanning electron microscopy), microbial surface hydrophobicity measurements, and oral malodor reduction tests were performed using each extract. Statistical analyses were performed with IBM® SPSS® (version 24), using paired t-tests. Results: The mixed herbal extracts significantly inhibited the growth of Streptococcus mutans, Enterococcus faecalis, Candida albicans, and Porphyromonas gingivalis compared to the control (p < 0.001). Scanning electron microscopy results further revealed altered cellular morphology in the groups treated with the mixed herbal extracts. Additionally, the hydrophobicity assay results showed that the mixed herbal extracts reduced the oral adhesion capacities of bacteria (p < 0.001). Administration of the mixed herbal extracts also reduced the levels of volatile sulfur compounds, the main contributors to oral malodor (p < 0.001). Conclusions: Edible mixed herbal extracts can effectively eliminate oral pathogens and may be useful for improving oral health. The herbal extracts used were effective against all species of oral pathogens studied in this report.

Methanethiol: A Scent Mark of Dysregulated Sulfur Metabolism in Cancer.

In order to cope with increased demands for energy and metabolites as well as to enhance stress resilience, tumor cells develop various metabolic adaptations, representing a hallmark of cancer. In this regard, the dysregulation of sulfur metabolism that may result in elevated levels of volatile sulfur compounds (VSCs) in body fluids, breath, and/or excretions of cancer patients has recently gained attention. Besides hydrogen sulfide (H2S), methanethiol is the predominant cancer-associated VSC and has been proposed as a promising biomarker for non-invasive cancer diagnosis. Gut bacteria are the major exogenous source of exposure to this foul-smelling toxic gas, with methanethiol-producing strains such as Fusobacterium nucleatum highly abundant in the gut microbiome of colorectal carcinoma (CRC) patients. Physiologically, methanethiol becomes rapidly degraded through the methanethiol oxidase (MTO) activity of selenium-binding protein 1 (SELENBP1). However, SELENBP1, which is considered a tumor suppressor, is often downregulated in tumor tissues, and this has been epidemiologically linked to poor clinical outcomes. In addition to impaired removal, an increase in methanethiol levels may derive from non-enzymatic reactions, such as a Maillard reaction between glucose and methionine, two metabolites enriched in cancer cells. High methionine concentrations in cancer cells may also result in enzymatic methanethiol production in mitochondria. Moreover, enzymatic endogenous methanethiol production may occur through methyltransferase-like protein 7B (METTL7B), which is present at elevated levels in some cancers, including CRC and hepatocellular carcinoma (HCC). In conclusion, methanethiol contributes to the scent of cancer as part of the cancer-associated signature combination of volatile organic compounds (VOCs) that are increasingly being exploited for non-invasive early cancer diagnosis.

Oral microbiome as a co-mediator of halitosis and periodontitis: a narrative review.

Halitosis or oral malodor is an unpleasant odor from the oral cavity. However, although patients with periodontitis often complain of halitosis, their relationship has not been fully elucidated. We reviewed previous literature based on the hypothesis that the relationship between halitosis and periodontitis is mediated by the oral microbiome. This narrative review sought to provide insight into the causative role of the oral microbiome in influencing halitosis and periodontitis. In addition, we tried to deepen knowledge related to the relationship between halitosis and periodontitis generated by the oral microbiome accumulated over the past 40 years. From 1984 to 2023, a total of 106 papers that carefully and scientifically dealt with halitosis and periodontitis were included in this narrative review. Based on previous results, halitosis and periodontitis were closely related. For decades, researchers have taken an intriguing approach to the question of whether there is a relationship between halitosis and periodontitis. Central factors in the relationship between halitosis and periodontitis include volatile sulfur compounds (VSCs), the oral microbiota that produce VSCs, and the inflammatory response. Taken together, the more severe periodontitis, the higher the level of VSC in halitosis, which may be mediated by oral microbiome. However, the relationship between the occurrence, maintenance, and exacerbation of periodontitis and halitosis is not a necessary and sufficient condition for each other because they are complex interplay even in one individual.

Investigation of volatile sulfur compound level and halitosis in patients with gingivitis and periodontitis

This study aimed to measure the levels of volatile sulfur compounds and investigate the occurrence of halitosis in patients with gingivitis and periodontitis. Additionally, the incidence rates of gingivitis and periodontitis in patients with halitosis were investigated. Through various statistical analyses, we attempted to determine the relationship between periodontal disease and halitosis. One-hundred-and-four participants (52 females and 52 males, mean age: 46.49 ± 16.03 years) were enrolled in this cross-sectional study, comprising 33 healthy controls, 43 patients with gingivitis, and 28 patients with periodontitis. Gas chromatography was used to measure hydrogen sulfide (H2S) and methyl mercaptan (CH3SH), which are representative VSCs. The VSC cut-off values for diagnosing halitosis were 65.79 ppb for women and 79.94 ppb for men. Total VSC level was significantly higher in the gingivitis than the healthy control group (186.72 ± 374.83 ppb vs. 19.80 ± 40.19 ppb, p = 0.035). There was no significant difference between the gingivitis and periodontitis (153.79 ± 278.51 ppb) groups. H2S level was significantly higher in the gingivitis (100.51 ± 183.69 ppb) and periodontitis (91.57 ± 132.06 ppb) groups than in healthy controls (14.97 ± 31.22 ppb), and CH3SH level was significantly higher in gingivitis group (29.31 ± 59.16 ppb) than in the healthy control (5.73 ± 14.10 ppb) (all p < 0.05). Halitosis was found in 3% of healthy controls and 39.5% and 42.9% of patients with gingivitis and periodontitis patients, respectively, making it significantly higher in the gingivitis and periodontitis groups than the healthy controls (p = 0.005). Conversely, among participants with halitosis, 53.1% had gingivitis, 37.5% had periodontitis, and 90.6 incidence had periodontal disease. Multivariate logistic regression analysis to predict the presence of halitosis, found periodontal disease was a significant predictor of halitosis (OR = 3.607, 95% CI 1.023–12.718, p = 0.046). Considering area under curve value for halitosis, the cut-off value of healthy control (H2S:61.5 ppb, CH3SH:3.5 ppb), gingivitis (H2S:50.0 ppb, CH3SH:6 ppb), and periodontitis (H2S:62.0 ppb, CH3SH:3.5 ppb) were (all p < 0.05). Our results emphasize the close and strong relationship between periodontal disease and halitosis through human clinical evidence based on the high co-occurrence rate of mutual diseases. Additionally, the presence of periodontal disease increased the probability of halitosis by 3.607 times. These results suggest that H2S can be used as a biomarker of halitosis in patients with periodontal disease.