Menthol, menthone, menthyl acetate menthofuran

Mentha piperita (-)-Menthol, (-)-menthone, (-)-menthyl acetate, (+)-menthofuran, a-pinene, a-phellandrene. 

Lane 1 menthol, menthone lane 2 menthyl acetate, menthofuran lanes 3- 8 peppermint oils from different manufacturers... 

A cultivar of M. arvensis has been reported to contain high concentrations of menthofuran (42%) and lesser amounts of menthol (21%), menthyl acetate (14%), and menthone (0.71%). ... 

Fig. 2 Fluorescence scan of a chromatogram of peppermint oil menthol (1), cineole (2), menthone (3), menthyl acetate (4), menthofuran/terpenes (5).

Composition 30-55% (-)-menthol, 14-32% (-)-menthone, 1.5-10% (-i-)-iso menthone, 2.8-10% menthyl acetate, 3.5-14% 1,8-cineole, 1-9% menthofuran, up to 4% pule-gone [220], as well as 3-octanol, trans-sabinene hydrate, piperitone, viridrflorol, mono- and sesquiterpene hydrocarbons. For further constituents see [221, 222, 223[. On the differentiation between peppermint oils and the detection of dementholised commint oil as a major adulterant see the results of Lawrence et al. [224], The ratio of 1,8-cineole limonene (min. 2) was even implemented in the European Pharmacopoeia. The latter also limits the isopulegol content for Mentha piperita oil to 0.2%. 

As in commint oil, the main component of peppermint oil is (-)-menthol (34— 46%) it also contains (-)-menthone (15-27%) and (-)-menthyl acetate (2.5-7 %). However, peppermint oil, unlike cornmint oil, has a higher content of (+)-menthofuran [17957-94-7] (0.5-6%). These data refer to oils of US type oils of other origins (China, India) may have slightly different compositions [628-6331]. 

Presumably the most studied essential oil plant is peppermint (Mentha x piperita L.). Already in the 1950s Lemli (1955) stated that the proportion of menthol to menthone in peppermint leaves changes in the course of the development toward higher menthol contents. Lawrence (2007) has just recently shown that from immature plants via mature to senescent plants the content of menthol increases (34.8-39.9 8.2%) and correspondingly the menthone content decreases dramatically (26.8-17.4-4.7%). At the same time, also an increase of menthyl acetate from 8.5% to 23.3% of the oil could be observed. At full flowering, the peppermint herb oil contains only 36.8% menthol but 21.8% menthone, 7.7% menthofuran, and almost 3% pulegone due to the fact that the flower oils are richer in... 

Peppermint yields 0.1-1.0% (usually 0.3-0.4%) of volatile oil that is composed mainly of menthol (29 8%), menthone (20-31%), and menthyl acetate (ca. 310%), with smaller amounts of menthofuran (1-7%) and limonene. Other constituents present in... 

Cornmint contains 1-2% volatile oil that consists of a high concentration of menthol (70-95%), menthone (10-20%), menthyl acetate, isomenthone, thujone, api-nene, phellandrene, piperitone, menthofuran, and others (jiangsu list and horhammer ... 

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