# Human axillary odors and their precursors in normal and stressful situations **URL:** \ **Category:** Studies & Abstracts\ **Created:** [January 13, 2007, 3:09am UTC](https://pheromonetalk.com/t/human-axillary-odors-and-their-precursors-in-normal-and-stressful-situations/1543 "2007-01-13T03:09:10Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Socrates](https://avatars.discourse-cdn.com/v4/letter/s/3bc359/32.png) [@Socrates](https://pheromonetalk.com/u/Socrates)\ **Post date:** [January 13, 2007, 3:09am UTC](https://pheromonetalk.com/t/human-axillary-odors-and-their-precursors-in-normal-and-stressful-situations/1543/1 "2007-01-13T03:09:10Z")
[http://www.achems.org/clientuploads/Abstracts2006Meeting.pdf?PHPSESSID=43d2ed12f6b4ee1ca08f68333e4dcf6d](http://www.achems.org/clientuploads/Abstracts2006Meeting.pdf?PHPSESSID=43d2ed12f6b4ee1ca08f68333e4dcf6d) ANALYSES OF HUMAN AXILLARY ODORS AND THEIR PRECURSORS IN NORMAL AND STRESSFUL SITUATIONS Yabuki M.1, Takeuchi K.1, Hagura T.1, Hasegawa Y.1 1Tokyo Research Laboratory, Kao Corporation, Tokyo, Japan Our laboratory previously reported the 3-Hydroxy-3-methylhexanoic acid (3H3MH) and 3-methyl-3-sulfanylhexan-1-ol (3M3SH) as key odorants in human axillary sweat (Hasegawa, 2004). We had also elucidated the occurrence of cysteine-linked precursor of 3M3SH on the axillary skin and applied for a patent for the use of body odor indicator (Yabuki, 2004). One objective of this study is to analyze amino acid linked axillary odor precursors quantitatively. A second objective is to evaluate the effect of mentally stressful situation on axillary odor. In this study, we evaluated axillary odor of healthy American women (n = 26, aged 18-63) and collected their sweat samples in both normal (day 1. and mentally stressful situation (day 2). During 10-minute stress session trained moderator asked math, trivia and word questions to subjects continuously. LC-MS/MS analyses showed there was correlation between the precursor levels on skin surface and odor intensity. Whereas the ratios of glutamine-linked two odor precursors, Gln-3H3MH to Gln-3M2H (3-Methyl-2-Hexenoic acid) were approximately 7:1 with no inter-subject variation, the ratios of Gln- 3H3MH to Cys-3M3SH were unique to subjects. This finding indicates a presence of common synthetic pathway for the glutamine-linked 3H3MH and 3M2H. The temperature and other circumstances remained unchanged for testing two days. However, 70% of subjects of the day 2 had higher odor and precursor levels compared to day 1. Some subjects had more than three times higher amounts of precursors. This result suggests mental stress induced perspiration acts as an accelerator for strong odor formation.