Odor steroid

Nixon A., Mallet A.I., et al. (1988). Simultaneous quantification of five odorous steroids 16-Androstenes, in the axillary hair of men. J Steroid Biochem 29, 505-510. 

Laska, M., Wieser, A. and Salazar, L.T.H. (2005) Olfactory responsiveness to two odorous steroids in three species of nonhuman primates. Chem. Sens. 30, 505-511. 

In other species, especially the Gottingen miniature pig, Booth established that androgens promote the abundant appearance of distinctive metabolites of testosterone, often exceeding 2 mmol/g wet weight [23]. The primary products are odorous steroids of the unusual 16a-androstene series, especially 3a-androstenol, 5a-... 

Whatever the physiology of odor perception may be, the sense of smell is keener than that of taste (22). If flavors are classed into odors and tastes as is common practice in science, it can be calculated that there are probably more than 10 possible sensations of odor and only a few, perhaps five, sensations of taste (13,21,35—37). Just as a hereditary or genetic factor may cause taste variations between individuals toward phenylthiourea, a similar factor may be in operation with odor. The odor of the steroid androsterone, found in many foods and human sweat, may eflcit different responses from different individuals. Some are very sensitive to it and find it unpleasant. To others, who are less sensitive to it, it has a musk or sandalwood-like smell. Approximately 50% of the adults tested cannot detect any odor even at extremely high concentrations. It is befleved that this abiUty is genetically determined (38). 

In a 250 ml Erlenmeyer flask covered with aluminum foil, 14.3 g (0.0381 mole) of 17a-acetoxy-3j5-hydroxypregn-5-en-20-one is mixed with 50 ml of tetra-hydrofuran, 7 ml ca. 0.076 mole) of dihydropyran, and 0.15 g of p-toluene-sulfonic acid monohydrate. The mixture is warmed to 40 + 5° where upon the steroid dissolves rapidly. The mixture is kept for 45 min and 1 ml of tetra-methylguanidine is added to neutralize the catalyst. Water (100 ml) is added and the organic solvent is removed using a rotary vacuum evaporator. The solid is taken up in ether, the solution is washed with water and saturated salt solution, dried over sodium sulfate, and then treated with Darco and filtered. Removal of the solvent followed by drying at 0.2 mm for 1 hr affords 18.4 g (theory is 17.5 g) of solid having an odor of dihydropyran. The infrared spectrum contains no hydroxyl bands and the crude material is not further purified. This compound has not been described in the literature. 

Cellular functions are controlled by extracellular signals such as hormones, neurotransmitters, odorants, light and other chemical or physical stimuli. Only a few of these signal molecules, e.g., the highly lipid-soluble steroids or thyroid hormones, can diffiise across the... 

Here is a bit of a complication there is a lot of individual variation in the sense of human olfaction. Not everything smells the same to everyone. This holds both for the intensity of the perceived smeU as well as for its quality pleasant, floral, skunky, sweaty, or no odor at all. Andreas Keller has recently demonstrated that some significant part of this individual variation in the sense of smell derives from genetic variation in human odorant genes. Specifically, two single nucleotide polymorphisms (SNPs), leading to two amino acid substitutions in an odorant receptor, have dramatic affects on the perception of the odor of androstenone, a steroid derived from testosterone. 

Besides steroids, axillary odor also contains normal, branched, unsaturated aliphatic acids with 6 to 11 carbon members. Most abundant is (E)-3-methyl-2-hexenoic acid. Both this compound and its (Z)-isomer are found in the aqueous phase hydrolysate and the aqueous phase incubated with bacteria. It is assumed that precursors are water soluble and converted to odoriferous compounds by the axillary flora (Zeng etal., 1992). 

Male odor accelerates puberty in the domestic pig. The two steroids 5a-androstenone (5o -androst-16-en-3-one) and 3a-androstenol (5o -androst-16-en-3-ol) play a role in this effect (Booth, 1984). 

Male axillary odor, thought to arise from volatile acids and volatile steroids, was collected on pads worn in the armpit for 6-9 hours. Alcohol extract of these samples was applied to the upper lip of each subject and left there for at least 6 hours. The cycles of women receiving the axillary extract three times per week for an average of 13.5 weeks became less variable and the number of aberrantly long cycles was reduced. 

Gower, D. B., Watkins, J., Mallett, A. L, Rennie, P. J., and Holland, K. T. (1989). Transformations of odorous 16-androstene steroids by human axillaiy coiyneform bacteria. Chemical Senses 14,208. 

A very specific relationship exists between chemical structure and odor quality this has been defined for a number of odorant classes, for example steroids and mu compounds (76). The chirality as well as the flexibility of a molecule is also important in deling the odor. A structure that can assume different conformations could interact with more than one receptor type and elicit more than one odor quality. Thus one typically observes several odor descriptors used for compounds... 

Virtually all people lack the ability to detect some specific odors. A striking example of such an anosmia is the inability to smell the volatile steroid androsten-one (5a-androst-16-en-3-one), a constituent of perspiration, of some pork products, truffles, and celery.922... 

Table I summarizes the various meats, meat constituents, and other related substances which have been analyzed, including substances reported on previously (6) as well as those for which new data are given. The substances chosen are intended to provide a cross-section of the type of inherently related material from which volatile irradiation odor and flavor compounds might be expected to form. Thus, in addition to several whole meats, the volatile irradiation products from a number of protein and lipid substances have been analyzed. Among the lipid substances included are typical whole fats and separate moieties such as triglycerides, fatty acid esters, and cholesterol, as an example of a steroid. Among the proteinaceous substances included are a protein, a polypeptide, and some individual amino acids. Finally, beef itself has been separated into a protein, a lipid, and a lipoprotein fraction, and these have been separated, irradiated, and analyzed.

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