P-bisabolene

Aerial parts of N. sintenisii yielded 0.3% of a clear yellowish oil. Forty constituents (96.5% of the total oil) were identified. The main components were 4aP,7a,7aP-nepetalactone (23.4%), elemol (16.1%), E- -farnesene (9.5%), 1,8-cineole (8.2%), cw-sabinene hydrate (6.5%), P-bisabolene (4.2%), germacrene-D (3.5%), P-sesquiphellandrene (2.8%), P-bourbonene (1.5%) and a-epi-cadinol (1.3%). According to available data, Nepeta species can be divided into two groups of nepetalactone-containing and nepetalactone-free species. The results of this study indicate that the compositions of volatile oil of N. sintenisii are similar to the other Nepeta genus and this plant could be classified in the group which 4aP,7a,7aP-nepetalactone is the major component of their oils. 

A pale olive green essential oil with a sharp, warm, woody spicy odour. Principal constituents are monoterpenes limonone (15-17%), sabinene (9-19%), (l-pinene (5-14%), a-pinene (2-11%), P-myrcene (1.5-2.5%), carene (0.2-14.0%), a-phellandrene (0.5-5.0%), sesquiterpenes P-caryphyllene (9-31%), P-bisabolene (0.1-5.1%) and p-farnescene (1-3%). Box 7.15 shows a chemical analysis and Box 7.16 is a material safety data sheet from a sup-... 

Composition Main constituent is zingiberene (>30%) followed by P-sesquiphelland-rene. (-H)-ar-curcumene, (E,E)-a-famesene and (-)-P-bisabolene are further important sesquiterpene hydrocarbons. a-Terpineol and citral (up to 9% in Australian ginger) result in the citrus note, whereas nerolidol is responsible for the woody-soapy taste [115]. Further constituents are camphene, limonene, phellandrene, bomeol, 1,8-cine-ole, linalool, a-bisabolene, oxygenated sesquiterpene hydrocarbons, etc. For recent analytical data see [116, 117, 118]. 

A low yield synthesis of p-bisabolene (104) has been achieved by reaction of ( +)-limonene with acetic acid and acetic anhydride in the presence of manganese (III) acetate to give the acid (105) which could be converted into p-bisabolene in... 

Figure 3. Ginger 1 - 1.8-cineole, 2 - oc-terpinolene, 3 - zingiberene, 4 - P-bisabolene, 5 - y-cadinene, 6 -P-sesquiterpene.

C Zingiberis rhizoma (2a). The commercial oil is characterized by the high amount of the blue THC zone at the solvent front (zingiberene, P-bisabolen, sesquiphellandrene) and the blue zones at Rf 0.45-0.5 (e.g. cltral). Pungent principles are not detectable in the essential oil (compare with sample 2, Fig. 3C). 

Urzua et al. reported that a terpenoid mixture from a nonpolar fraction of the roots of A. chilensis completely inhibited the germination of lettuce and wheat seeds, partially the germination of onion and carrot seeds and is inactive with raddish and beans [312], The principal components of the terpenoid mixture, (-)-P-bisabolene (264) and (+)-P-sesquiphyllandrene (266), showed different inhibitory properties from those of the mixture. 

Compounds 8-11 belonged to the bisabolane family of sesquiterpenes. Bisabolane sesquiterpenes are not typical microbial metabolites. Most compounds of this skeletal class have been isolated from numerous terrestrial plants, a basidiomycete [101], sponges [102-103], octocoral [104, 105], and red algae [106], To our knowledge there have been two reports of bisabolanes from fungi. The first report in 1989 was of a mycotoxin from Fusarium sambucinum [107], More recently, mass spectral analysis of the volatile constituents of toxigenic Penicillium roqueforti strains yielded P-bisabolene [108]. 

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