Relationship between volatile sulphide compounds concentration and oral bacteria species detection in the elderly

Nonvolatile S-alk(en)ylthio-L-cysteine derivatives in fresh onion (Allium cepa L. cultivar)

The L-cysteine derivatives (R)-2-amino-3-(methyldisulfanyl)propanoic acid (S-methylthio-L-cysteine), (R)-2-amino-3-(propyldisulfanyl)propanoic acid (S-propylthio-L-cysteine), (R)-2-amino-3-(1-propenyldisulfanyl)propanoic acid (S-(1-propenylthio)-L-cysteine), and (R)-2-amino-3-(2-propenyldisulfanyl)propanoic acid (S-allylthio-L-cysteine) were prepared from 3-[(methoxycarbonyl)dithio]-L-alanine, obtained from the reaction of L-cysteine with methoxycarbonylsulfenyl chloride. The occurrence of these S-(+)-alk(en)ylthio-L-cysteine derivatives in onion (Allium cepa L.) was proven by using UPLC-MS-ESI(+) in SRM mode. Their concentrations in fresh onion were estimated to be 0.19 mg/kg S-methylthio-L-cysteine, 0.01 mg/kg S-propylthio-L-cysteine, and 0.56 mg/kg (S-(1-propenyllthio)-L-cysteine, concentrations that are about 3000 times lower than that of isoalliin (S-(1-propenyl-S-oxo-L-cysteine). These compounds were treated with Fusobacterium nucleatum, a microorganism responsible for the formation of mouth malodor. These L-cysteine disulfides were demonstrated to predominantly produce tri- and tetrasulfides. Isoalliin is almost entirely consumed by the plant enzyme alliin lyase (EC 4.4.1.4 S-alk(en)yl-S-oxo-L-cysteine lyase) in a few seconds, but it is not transformed by F. nucleatum. This example of flavor modulation shows that the plant produces different precursors, leading to the formation of the same types of volatile sulfur compounds. Whereas the plant enzyme efficiently transforms S-alk(en)yl-S-oxo-L-cysteine, mouth bacteria are responsible for the transformation of S-alk(en)ylthio-L-cysteine.

Relationship between oral status and prevalence of periodontopathic bacteria on the tongues of elderly individuals

Colonization of periodontopathic bacteria is associated with increased risk of systemic diseases. However, few studies have investigated the relationships between oral status factors and health-related quality of life (HR-QOL) and the prevalence of such bacteria in elderly individuals. This study investigated the prevalence of Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola and Tannerella forsythia in 165 community-dwelling functionally independent 85-year-old Japanese individuals (93 dentate, 72 edentulous) and the relationship to oral status, including oral malodour and HR-QOL. All four of the studied periodontopathic bacteria were found more frequently in tongue coating samples from dentate than edentulous subjects, and the prevalence of Porphyromonas gingivalis, Prevotella intermedia and Treponema denticola was significantly related to the number of teeth with a periodontal pocket depth ≥4 mm. These results suggest the existence of a stable circulation of periodontopathic bacteria between the gingival sulcus and tongue coating over time with teeth. In addition, the presence of teeth with a deep pocket and colonization of Treponema denticola were positively related to the level of CH(3)SH, whilst the number of present teeth contributed positively to HR-QOL, especially with regard to mental health. In conclusion, as the dentate state can retain colonization of periodontopathic pathogens in the oral cavity, both periodontal treatment and tongue care are important for maintaining a healthy oral status in the elderly, and possibly result in avoidance of risk for tooth loss and decline in HR-QOL, as well as protecting from systemic diseases.

A review of the current literature on aetiology and measurement methods of halitosis

OBJECTIVES

This work reviews the current knowledge of aetiology and measurement methods of halitosis.

DATA

Halitosis is an unpleasant or offensive odour emanating from the breath. The condition is multifactorial and may involve both oral and non-oral conditions.

SOURCES

A private, monthly with keywords halitosis, malodo(u)r, (a)etiology, measurement, and management from Medline and Pubmed updated database of literature was reviewed.

CONCLUSIONS

In approximately 80-90% of all cases, halitosis is caused by oral conditions, defined as oral malodour. Oral malodour results from tongue coating, periodontal disease, peri-implant disease, deep carious lesions, exposed necrotic tooth pulps, pericoronitis, mucosal ulcerations, healing (mucosal) wounds, impacted food or debris, imperfect dental restorations, unclean dentures, and factors causing decreased salivary flow rate. The basic process is microbial degradation of organic substrates. Non-oral aetiologies of halitosis include disturbances of the upper and lower respiratory tract, disorders of the gastrointestinal tract, some systemic diseases, metabolic disorders, medications, and carcinomas. Stressful situations are predisposing factors. There are three primary measurement methods of halitosis. Organoleptic measurement and gas chromatography are very reliable, but not very easily clinically implemented methods. The use of organoleptic measurement is suggested as the 'gold standard'. Gas chromatography is the preferable method if precise measurements of specific gases are required. Sulphide monitoring is an easily used method, but has the limitation that important odours are not detected. The scientific and practical value of additional or alternative measurement methods, such as BANA test, chemical sensors, salivary incubation test, quantifying beta-galactosidase activity, ammonia monitoring, ninhydrin method, and polymerase chain reaction, has to be established.

Inhibitory effect of Weissella cibaria isolates on the production of volatile sulphur compounds

AIMS

The objective of this study was to characterize the inhibitory effects of Weissella cibaria isolates on volatile sulphur compounds (VSC) production both in vitro and in vivo.

MATERIAL AND METHODS

We isolated and identified three hydrogen peroxide-generating lactobacilli from children's saliva, and assessed their inhibitory effects on VSC production and Fusobacterium nucleatum proliferation. Clinical studies were conducted with 46 subjects in order to measure the VSC of their mouth air.

RESULTS

These lactobacilli were identified as W. cibaria. These isolates inhibited the production of VSC by F. nucleatum (p<0.05). The concentration of F. nucleatum was decreased by 5-log cycles as a result of exposure to the W. cibaria strains (p<0.05), whereas the catalase-treated W. cibaria cultures exerted no evident inhibitory effects on F. nucleatum replication. In the clinical studies, gargling with one isolate resulted in a significant reduction in the levels of H2S and CH3SH by approximately 48.2% (p<0.01) and 59.4% (p<0.05), respectively.

CONCLUSIONS

These results indicate that W. cibaria isolates possess the ability to inhibit VSC production under both in vitro and in vivo conditions, demonstrating that they bear the potential for development into novel probiotics for use in the oral cavity.