Deodorizing Mechanism of (–)-Epigallocatechin Gallate against Methyl Mercaptan

Yasuda, Hideyuki; Arakawa, Tsutomu

doi:10.1271/bbb.59.1232

Cited by 64 publications

(62 citation statements)

References 8 publications

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“…A factor of much importance while testing deodorant activity might be the surface area of the product in contact with the environment inside the test tube. The green tea was provided in powdered form to begin with and thus had a large surface area; therefore, the reaction of CH3SH with the hydroxyl groups in the B ring of EGCg could proceed quickly (14). On the other hand, the toothpaste was in a semi-solid form but demonstrated complete deodorant activity against H2S; vaporized mint oil or similar compounds in toothpaste might react with H2S very quickly.…”

Section: Discussionmentioning

confidence: 99%

“…Green tea is heated after harvesting to stop this reaction; otherwise green teas would be easily oxidized and become fermented teas such as an ordinary tea or black tea. The B ring of EGCg is perhaps necessary for reaction with VSCs, more so than the galloyl moiety (14). Therefore, if this ring undergoes a dehydration reaction with another molecule, such as tannin, or if the B ring is altered, it can no longer form the transition state and thus may not react with VSCs to form a stable benzene ring via resonance.…”

Section: Discussionmentioning

confidence: 99%

“…There are some reports to suggest the effect of green tea or tea catechins on oral malodor (14,32). A clinical study has shown a large reduction of oral malodor by tea catechin (32).…”

Section: Discussionmentioning

confidence: 99%

“…Green tea contains tea catechins in which ( Ϫ )-epigallocatechin gallate (EGCg) is known to dominate ( 10 ). To explain the deodorant activity of ECGs, Yasuda and Arakawa ( 14 ) proposed a pathway whereby EGCg reacted with CH 3 SH with the hydroxyl groups in the B ring instead of those on the galloyl moiety, increasing the reaction. However, the effect of green tea on oral malodor has not yet been described in an in vivo study.…”

mentioning

confidence: 99%

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Effect of Green Tea on Volatile Sulfur Compounds in Mouth Air

Lodhia

Yaegaki

Khakbaznejad

et al. 2008

J Nutr Sci Vitaminol

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Summary Many food products are claimed to be effective in controlling halitosis. Halitosis is caused mainly by volatile sulfur compounds (VSCs) such as H 2 S and CH 3 SH produced in the oral cavity. Oral microorganisms degrade proteinaceous substrates to cysteine and methionine, which are then converted to VSCs. Most treatments for halitosis focus on controlling the number of microorganisms in the oral cavity. Since tea polyphenols have been shown to have antimicrobial and deodorant effects, we have investigated whether green tea powder reduces VSCs in mouth air, and compared its effectiveness with that of other foods which are claimed to control halitosis. Immediately after administrating the products, green tea showed the largest reduction in concentration of both H 2 S and CH 3 SH gases, especially CH 3 SH which also demonstrated a better correlation with odor strength than H 2 S; however, no reduction was observed at 1, 2 and 3 h after administration. Chewing gum, mints and parsley-seed oil product did not reduce the concentration of VSCs in mouth air at any time. Toothpaste, mints and green tea strongly inhibited VSCs production in a saliva-putrefaction system, but chewing gum and parsley-seed oil product could not inhibit saliva putrefaction. Toothpaste and green tea also demonstrated strong deodorant activities in vitro, but no significant deodorant activity of mints, chewing gum or parsley-seed oil product were observed. We concluded that green tea was very effective in reducing oral malodor temporarily because of its disinfectant and deodorant activities, whereas other foods were not effective.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

“…There are some reports to suggest the effect of green tea or tea catechins on oral malodor (14,32). A clinical study has shown a large reduction of oral malodor by tea catechin (32).…”

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Effect of Green Tea on Volatile Sulfur Compounds in Mouth Air

Lodhia

Yaegaki

Khakbaznejad

et al. 2008

J Nutr Sci Vitaminol

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show abstract

“…Similarly, o-quinone generated by polyphenol oxidase have been shown to play a critical role in the methyl mercaptan capturing properties of mushroom 18 . In addition, o-quinones were found to be intermediates that produced methylthio adducts in the case of catechins, such as epigallocatechin gallate EGCG 19 . These reactions were considered to be the main factors responsible for the deodorizing activities observed.…”

Section: Evaluation Of Deodorizing Activitymentioning

confidence: 99%