Mints Mentha spp

HAUDENSCHILD, C., SCHALK, M., KARP, F., CROTEAU, R. Functional expression of regiospecific cytochrome P450 limonene hydroxylases from mint (Mentha spp.) in Escherichia coli and Saccharomyces cerevisiae, Arch. Biochem. Biophys., 2000,379, 127-136. 

Menthol is a well-known terpenoid from the essential oil of mint Mentha spp.) (15), and is described here as a representative of the different acyclic and cyclic plant monoterpenoids. Because of its pleasant odor, taste, and anesthetic and antimicrobial effects, (-)-menthol is an industrially important terpenoid and is produced commercially in large scale both from the essential oils of Mentha spp. and by asymmetric synthesis. The essential oil is produced in glandular trichomes, which are secretory cells that number in the thousands on Mentha leaves. The presence of these specialized cells, which easily can be separated physically from other cell types, has greatly facilitated studying (-)-menthol biosynthesis. 

Some of the more interesting and attractive groups of native species include the skullcaps (Scutellaria spp.), physostegias (Physostegia spp.), hemp-nettles (Stachys spp.), sages (Salvia spp.), horse-mints or bergamots (Monarda spp.), bugle-weeds (Lycopus spp.), and tme mints (Mentha spp.). 

The most recent group of botanical products that have seen some commercial success as insecticides are the plant essential oils. Though some of these have traditional uses dating back decades, if not longer, commercialization has only taken place in the past 7-8 years. Plants producing essential oils that have been exploited for insect control include a number of herbs, most notably from the mint family (Lamiaceae), such as garden thyme Thymus vulgaris L.), rosemary Rosmarinus officinalis), and various species of mint Mentha spp.). ... 

Mint Mentha spp. menthol, pulegone Tetranychus urticae [14]... 

These are almost universal in essential oils, acting also as precursors of the more complex, oxidised terpenes. Limonene, for example, is the precursor of the main constituents of the monoterpenes in mints, Mentha spp. (Lamiaceae), including carvone and menthol... 

The most important compounds are menthadienes, derived from p-menthane, which differ in the positions of the double bonds (8-5). A common hydrocarbon is limonene (p-mentha-1,8-diene), which typically occurs in many essential oils (such as essential oils of citruses, mints and conifers) and turpentine. For example, the (-1-)-limonene isomer is the major component (>90%) ofessentialoilsof citrus peels, (-)-Kmonene is a component of essential oils of different types of mint Mentha spp., Lamiaceae) and conifers. Racemate, which is trivially known as dipentene, occurs in many essential oils. Other important menthadienes include a-terpinene (p-mentha-1,3-diene), y-terpinene (p-mentha-1,4-diene), a-phellandrene... 

Analysis of individual forms is also important to determine the authenticity of foods or essential oils. The presence of certain forms, such as the geometrical (E)-isomers, is often evaluated as an off-flavour. For example, (-F)-(E)-Hmonene (8-5) is a natural component of citrus essential oils and has a citrus smell like oranges. The isomer (-)-(S)-limonene (8-5), which is the main component of essential oils of silver fir Abies alba, Pinaceae), other conifers and various types of mints Mentha spp.), has a smell reminiscent of turpentine. The alcohol (-)-(E)-Hnalool, also known as licareol (8-18) has a strong woody smeU like lavender, but (-F)-(S)-isomer, also known as coriandrol (8-18) has a sweet smell with lavender tones. Another alcohol (-)-(E)-oct-l-en-3-ol (8-16), has an intense smell of fresh mushrooms, but (-F)-(S)-isomer (8-16) has a smell resembling vegetables with faint mushroom notes. The ketone (-)-(E)-carvone (8-50) has a mint-like smell (and is the main component of spearmint essential oil), while its isomer (-F)-(S)-... 

C oH,gO, Mr 154.25, liquid. Monocyclic monoter-pene ketones, the four optically active forms occur in nature. (-)-M. (ca. 35%) occurs in the essential oil of field mint (Mentha arvensis, Lamiaceae), (-i-)-M. in Micromelia biflora (Lamiaceae) ca. 56%, (-i-)-iso-M. in Micromelia abyssinica ca. 42%, and (-)-iso-M. in geranium oil (Pelargonium spp., Geraniaceae). p-M. is used in perfumes as a mixture with other fragrance substances. 

Synonyms Cyclohexanol, 2-isopropyl-5-methyl- Cyclohexanol, 5-methyl-2-(1-methylethyl)- Hexahydrothymol 2-lsopropyl-5-methylcyclohexanol 3-p-Menthanol p-Menthan-3-ol 5-Methyl-2-isopropylcyclohexanol 5-Methyl-2-isopropyl hexahydrophenol 5-Methyl-2-(1-methylethyl) cyclohexanol Peppermint camphor Racemic menthol Classification Diterpene alcohol Definition Alcohol obtained from diverse mint oils, Mentha spp. or prepared synthetically may be levorotatory (I-), from natural or syn. sources, or racemic (dl-)... 

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