Suppression of microbial metabolic pathways inhibits the generation of the human body odor component diacetyl by Staphylococcus spp.
Diacetyl (2,3-butanedione) is a key contributor to unpleasant odors emanating from the axillae, feet, and head regions. To investigate the mechanism of diacetyl generation on human skin, resident skin bacteria were tested for the ability to produce diacetyl via metabolism of the main organic acids contained in human sweat. L-lactate metabolism by Staphylococcus aureus and Staphylococcus epidermidis produced the highest amounts of diacetyl, as measured by high-performance liquid chromatography. Glycyrrhiza glabra root extract (GGR) and α-tocopheryl-L-ascorbate-2-O-phosphate diester potassium salt (EPC-K1), a phosphate diester of α-tocopherol and ascorbic acid, effectively inhibited diacetyl formation without bactericidal effects. Moreover, a metabolic flux analysis revealed that GGR and EPC-K1 suppressed diacetyl formation by inhibiting extracellular bacterial conversion of L-lactate to pyruvate or by altering intracellular metabolic flow into the citrate cycle, respectively, highlighting fundamentally distinct mechanisms by GGR and EPC-K1 to suppress diacetyl formation. These results provide new insight into diacetyl metabolism by human skin bacteria and identify a regulatory mechanism of diacetyl formation that can facilitate the development of effective deodorant agents.
Technical Development Center, Mandom Corp., Osaka, Japan.
Takeshi
T
Hara
Technical Development Center, Mandom Corp., Osaka, Japan.
Hiroshi
H
Matsui
Technical Development Center, Mandom Corp., Osaka, Japan.
Hironori
H
Shimizu
D002247:Carbon Isotopes / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D019343:Citric Acid / Q000737:chemistry; D003358:Cosmetics; D003931:Diacetyl / Q000737:chemistry*; D005227:Fatty Acids / Q000737:chemistry; D006019:Glycolysis; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D008297:Male; D008855:Microscopy, Electron, Scanning; D009812:Odorants; D019289:Pyruvic Acid / Q000737:chemistry; D012867:Skin / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000378:metabolism*; D013212:Staphylococcus epidermidis / Q000378:metabolism*; D013542:Sweat / Q000737:chemistry*
D002247:Carbon Isotopes; D003358:Cosmetics; D005227:Fatty Acids; D019343:Citric Acid; D019344:Lactic Acid; D019289:Pyruvic Acid; D003931:Diacetyl