Effects of matsutake mushroom scent compounds on tyrosinase and murine B16-F10 melanoma cells.

Tyrosinase-catalyzed l-tyrosine oxidation is a key step in melanogenesis, and intense melanin formation is often a problem in chemotherapies or food preservation. Here we report that methyl cinnamate one of the constituents characterized from mycelium and sporocarp of American matsutake mushroom Tricholoma magnivelare inhibits both enzymatic and cellular melanin formation. Methyl cinnamate inhibits mushroom tyrosinase-catalyzed l-tyrosine oxidation while the oxidation of l-3,4-dihydroxyphenylalanine (l-DOPA) was not inhibited. In subsequent cellular assays, methyl cinnamate significantly suppressed melanogenesis of murine B16-F10 melanoma cells without affecting cell growth. However, methyl 3-phenylpropionate, a dihydro-derivative of methyl cinnamate, did not possess melanogenesis, indicating that the double bond in the enone moiety is a key Michael reaction acceptor to elicit the activity. In addition, a rather rare chlorinated benzaldehyde derivative, 3,5-dichloro-4-methoxybenzaldehyde isolated from the same source, was found to show potent cytotoxicity, and the chlorine atom reduced a tyrosinase inhibitory activity but enhanced cytotoxicity. Our findings suggest that methyl cinnamate is a novel melanogenesis inhibitor from natural sources.

Synthesis and antimicrobial activity of long-chain 3,4-Epoxy-2-alkanones.

3,4-Epoxy-2-dodecanone, a major component in the preorbital gland of the African grey duiker (Sylvicapra grimmia), showed antimicrobial activity in preliminary tests. The C(11) to C(17) homologues of this compound were prepared and their activity against several pathogenic dermal bacteria and fungi was tested. 3,4-Epoxy-2-dodecanone and 3,4-epoxy-2-tridecanone inhibited the growth of Trichophyton mentagrophytes at 25 Îg/mL. Moderate inhibition of the growth of the bacteria Propionibacterium acnes and the lipophilic yeast, Pityrosporum ovale, was seen for several of the homologues.

Antimicrobial activity of long-chain (E)-3-alken-2-ones.

(E)-3-tridecen-2-one, a compound identified from the interdigital glands of black-tailed deer (Odocoileus hemionus columbianus), has been shown to inhibit the growth of bacteria and fungi. Homologues of (E)-3-tridecen-2-one were prepared and screened for antimicrobial activity. For the fungus, Trichophyton mentagrophytes, the minimum inhibitory concentration (MIC) of (E)-3-Tetradecen-2-one was 12.5 microg/mL, and for the bacteria, Propionibacterium acnes, the MIC of (E)-3-heptadecen-2-one was 3.13 microg/mL.

Volatile compounds in shoulder gland secretions of male flying foxes, genus Pteropus (Pteropodidae, Chiroptera).

The shoulder gland secretions of captive males of the Indian flying fox (Pteropus giganteus), the little golden-mantled flying fox (P. pumilus), the island flying fox (P. hypomelanus), and the large flying fox (P. vampyrus) were examined by gas chromatography-mass spectrometry. Sixty-five compounds, including hydrocarbons, carboxylic acids, alcohols, aldehydes, ketones, esters, and amides, were identified among the four species. Many of these compounds, such as squalene, cholesterol, and C5-C16 straight- and branched-chain carboxylic acids, are typical of tetrapod epidermal products. Aldehydes, which were detected in all four Pteropus species, and some straight- and branched-chain ketones, which were detected in P. hypomelanus and P. pumilus, are known from other mammalian skin glands. Acetophenone, 4-acetoxyacetophenone, and 4-hydroxyacetophenone were observed in P. pumilus; the last compound comprised 37.1% of the total ion current. 2,3-Butanediol, a prominent component (5.2-19.3%) in the secretions of P. giganteus, P. hypomelanus, and P. pumilus, and C10 and C12 isopropyl esters and C10-C14 1-methylbutyl esters, observed in P. hypomelanus and P. vampyrus, have not previously been reported from vertebrates. alpha-Methyl-4-methoxybenzyl alcohol and dihydro-5-phenyl-2(3H)-furanone, from P. giganteus and P. pumilus, are new natural products. 1-Chloro-3-methyl-2-butene, another new natural product, and five C5 compounds exhibiting a similar isoprenoid structure were observed in P. giganteus. Striking contrasts were observed in the chemical profiles of the species we examined, with even general chemical classes differentially represented among them.

Volatile compounds from anal glands of the wolverine, Gulo gulo.

Dichloromethane extracts of wolverine (Gulo gulo, Mustelinae, Mustelidae) anal gland secretion were examined by gas chromatography-mass spectrometry. The secretion composition was complex and variable for the six samples examined: 123 compounds were detected in total, with the number per animal ranging from 45 to 71 compounds. Only six compounds were common to all extracts: 3-methylbutanoic acid, 2-methylbutanoic acid, phenylacetic acid, alpha-tocopherol, cholesterol, and a compound tentatively identified as 2-methyldecanoic acid. The highly odoriferous thietanes and dithiolanes found in anal gland secretions of some members of the Mustelinae [ferrets, mink, stoats, and weasels (Mustela spp.) and zorillas (Ictonyx spp.)] were not observed. The composition of the wolverine's anal gland secretion is similar to that of two other members of the Mustelinae, the pine and beech marten (Martes spp.).

Straight and branched-chain fatty acids in preorbital glands of sika deer, Cervus nippon.

Using GC-MS analysis, 11 major volatile compounds were found in the preorbital gland secretion from a female sika deer, Cervus nippon. These compounds are the C14 through C18 straight-chain fatty acids, (ZZ)-9,12-octadecadienoic acid, 12-methyltridecanoic acid, 13-methyltetradecanoic acid, 14-methylpentadecanoic acid, 14-methylhexadecanoic acid, and 15-methylhexadecanoic acid. The five branched-chain acids make up over 29% of the volatiles in the gland. This is the first time branched-chain carboxylic acids have been reported from ungulate preorbital glands.

Clitolactone: a banana slug antifeedant from Clitocybe flaccida.

Clitolactone, 5-(chloromethyl)-3-methyl-2(5H)-furanone, was isolated from sporocaps of the mushroom Clitocybe flaccida. The structure was determined by HRMS, EIMS, (1)H & (13)C NMR, 2D (1)H-(13)C COSY and (1)H-(1)H COSY. This mushroom is not eaten by the banana slug Ariolimax columbianus (Gould), a mycophagist from the temperate rain forests of the Pacific Northwest. Clitolactone acts as an antifeedant because these slugs rejected 1.0 cm(2) pieces of lettuce treated with 25 µg of clitolactone.

Indole and 3-chloroindole: The source of the disagreeable odor of Hygrophorus paupertinus.

The odor emanating from sporocarps of Hygrophorus paupertinus is disagreeable and fecal-like. Solid phase microextraction (SPME) and analysis by gas chromatography-mass spectrometry (GC-MS) showed 1-octen-3-ol, indole and 3-chloroindole were responsible for the odor. This is the first case in which 3-chloroindole has been identified from a terrestrial organism.

Volatile components in metatarsal glands of sika deer, Cervus nippon.

GC-MS analysis of the metatarsal gland secretion from a female sika deer, Cervus nippon, showed 35 major volatile compounds that included 13 straight-chain carboxylic acids, a single branched-chain carboxylic acid, 9 straight-chain aldehydes, 3 monounsaturated aldehydes, 5 long-chain alcohols, a ketone, and cholesterol. The four most abundant compounds were heptanal, nonanal, octanoic acid, and 6-methyl-2-heptanone. Many of the compounds have previously been found in cervid secretions, but the unsaturated aldehydes, (E)-2-octenal, (E)-2-nonenal, and (E)-2-decenal, have not previously been reported in the glands of any cervid. The compounds in this gland may be pheromones, since metatarsal gland odor has been implicated in chemical communication among conspecifics of other cervids.

Volatile components in defensive spray of the hooded skunk, Mephitis macroura.

GC-MS analysis of the anal sac secretion from the hooded skunk, Mephitis macroura, showed the following seven major components comprised 99% of the volatiles in this secretion: (E)-2-butene-1-thiol, 3-methyl-1-butanethiol, S-(E)-2-butenyl thioacetate, S-3-methylbutenyl thioacetate, 2-phenylethanethiol, 2-methylquinoline, and 2-quinolinemethanethiol. Minor volatile components identified in this secretion are phenylmethanethiol, S-phenylmethyl thioacetate. S-2-phenylethyl thioacetate, bis[(E)-2-butenyl] disulfide, (E)-2-butenyl 3-methylbutyl disulfide, bis(3-methylbutyl) disulfide, and S-2-quinolinemethyl thioacetate. This secretion is similar to that of the striped skunk, Mephitis mephitis, differing only in that it contains four compounds not reported from the striped skunk: phenylmethanethiol, S-phenylmethyl thioacetate, 2-phenylethanethiol, and S-2-phenylethyl thioacetate.