Contents Sesquiterpenes

The second chemotype (their Type 1) had, in addition to the Type 0 array, substantial amounts of a-longipinene [297] and an unidentified sesquiterpene alcohol. The third chemotype (their Type 2) was distinguished by the presence of, among other compounds, cedrene isomers, [a-cedrene is shown as 298], and large amounts of the isomeric sesquiterpene alcohols a-acorenol [294] and its P-isomer [295]. The acora-diene isomers [295 and 296] were also identified. Some geographic patterning was observed in the Type 0 chemotype when the data were subjected to numerical analysis a trend in the reduction of caryophyllene content was revealed in a west to east direction. The data sets for Types 1 and 2 were too small to allow for similar analysis. 

These two examples demonstrate clearly the usefulness of SPME to detect volatile compounds in complex mixtures. Among the few sesquiterpenes identified in the SPME extract for the two samples, longifolene can be considered as a biomarker of a substance originating from a conifer tree. The absence of abietane or pimarane diterpenoids is indicative of the use of parts of the tree with low resin content. 

The highest contents of /-/-a-bisabololoxide A (39.9 7.5%) and /-/-a-bisabo-loloxide B (9.75 4.20%) are typical for chamomile plants, which flower anthodia were collected in various places in the East-Slovakian Lowland. In regard to following sesquiterpenes, the chamomile anthodia contain /-/-a-bisabolol (5.09 1.55%) and chamazrrlene (7.65 3.90%). 

The content of valepotriates and sesquiterpenes varies across species of the Valeriana genus. For example, Valeriana officinalis has relatively high content of sesquiterpenes and low content of valepotriates, while Valeriana edulis has a high proportion of valepotriates and low content of sesquiterpenes (Lindahl and Lindwall 1989). 

Barsby RW, Saian U, Knight DW, Houit JR. (1993). Feverfew and vascular smooth muscle extracts from fresh and dried piants show opposing pharmacoiogical profiles, dependent upon sesquiterpene iactone content. Planta Med. 59(1) 20-25. 

The capsules contained a mean of 82 mg feverfew and thus the level of activity calculated as parthenolide can be estimated as 0.67%. Other studies quote 0.87% sesquiterpene lactones calculated as parthenolide [27] and 0.25-0.30% of active (antimicrobial) material [33]. Bohlmann s extraction of individual components from the dried plant yielded 116 mg sesquiterpene lactones/kg dried feverfew which amounts to less than 0.01 % [17]. Another extraction yielded 330 mg endoperoxides/kg and 56 mg canin/kg alone [19] which would amount to a level of sesquiterpene lactones of at least 0.04%. Thus, the level of sesquiterpene lactones appears to vary with different sources of the plant and this could have been due to a number of factors including the conditions in which feverfew was grown, the season in which it was picked and the way in which it was stored. Another important determinant of the parthenolide content of feverfew appears to be the geographical location. A recent survey of commercial preparations found that all the North American commercial products tested contained less that 0.1% parthenolide, wheras much higher values were obtained for British products. A minimum level of 0.2% parthenolide in commercial products has been proposed by the Health Protection Branch of Health and Welfare Canada [71]. 

Quantitative analysis of feverfew with regards to sesquiterpene lactone content has been carried out by TLC [72,73] and HPLC [71,74,75] and H-NMR spectroscopy [75]. Measurements of parthenolide by HPLC correlated well with measurements by bioassays based on 5HT-secretion from platelets [75]. The availability of several techniques for quantitation of parthenolide levels in feverfew, makes some standardization of commercial preparations possible. 

Davidovich-Rikanati R, Lewinsohn E, Bar E, lijima Y, Pichersky E, Sitrit Y (2008) Overexpression of the lemon basil alpha-zingiberene synthase gene increases both mono- and sesquiterpene contents in tomato fruit. Plant J 56 228-238... 

The oils have a high terpene hydrocarbon content (>90%, mainly (+)-limonene), but their content of oxygen-containing compounds differs and affects their quality. Important for aroma are aldehydes, mainly decanal and citral, and aliphatic and terpenoid esters. The sesquiterpene aldehydes a-sinensal [17909-77-2] and/3-sinensal [6066-88-8], which contribute particularly to the special sweet orange aroma, also occur in other citrus oils, although in lower concentration [369-370a, 370d, 394,421, 430-438]. 

The tenacity of the highly complex vetiver oil is attributed to its high sesquiterpene content. The ketones ct-vetivone [15764-04-2] and /3-vetivone [18444-79-6], which usually form more than 10% of the oil, as well as khusimol [16223-63-5] (ca. 15%) and isovalencenol [22387-74-2] are the main constituents. 

Marine organisms have also been intensively examined for their sesquiterpene content. Dysidea herbacea is a sponge species which has yielded new metabolites for more than 20 years, and no doubt further collections from different locations will continue to reveal new chemistry. 

Main actives Sesquiterpene lactones, which are bitter flavoured, triterpenes, steroids, flavonoids, mucilages and an inulin content that varies from 2 to 40% in the autumn. Benefits The bitter components were used to promote the flow of digestive juices in the upper intestinal tract. 

Ginger oil displays considerable compositional diversity but is typically characterized by a high content of sesquiterpene hydrocarbons, including zingiberene, ar-curcumene, (3-bisabolene and (S-sesquiphellandrene. 

The essential oil content during the different stages of leaf growth revealed that the eugenol content in the leaves increased from 38.3 to 95.2% with maturity, while the contents of eugenyl acetate (51.2 to 1.5%) and caryophyllene (6.3 to 0.2%) decreased (Gopalakrishnan and Narayanan, 1988). Clove bud and leaf oil contain various classes of compounds, e.g. monoterpenes, sesquiterpenes, aldehydes and ketones (Vernin et al., 1994), which are indicated in Table 8.8. 

Nutmeg pericarp oil contained 16 monoterpenes (60%), nine monoterpene alcohols (29%), eight aromatic ethers (7%), three sesquiterpenes (1%), six esters (1%) and eight other minor components. The components were similar to those in nutmeg and mace oils but differed substantially in concentration (Table 9.11). The chief constituents were a-pinene, a-ter-pineol and terpinen-4-ol. The sabinene, myristicin and safrole concentrations were much lower, while the terpinen-4-ol and a-terpineol contents were much higher than in nutmeg and mace oils (Choo et al., 1999). The chief volatiles from nutmeg and mace are indicated in Fig. 9.1. 

GC-MS analysis to study the content and composition of extracts of celery revealed the presence of terpenoids, sesquiterpenoids and phthalides in the essential oils and extracts obtained with organic solvents from two celery cultivars (Wolski et al., 2004). The composition of the essential oil obtained from the fruits of three A. graveolens var. dulce cultivars, i.e. Helios, Orient and Zefir, showed that the main components of the essential oil were isoprenoids, including monoterpenes and sesquiterpenes. Essential oil content ranged from 2.5 to 3.0%. The percentage... 

The chief components of the celery leaf oil were limonene, myrcene and cis-ocimene (Bubarova, 1973 Fehr, 1974). The sesquiterpene content of the leaf oil (< 5%) was relatively low compared with that of the fruit oil. The essential oil of leaves contained a higher amount of limonene compared with the roots and a very small amount of carvone (Sipailiene et al., 2005). Studies conducted on the leaf essential oil showed that the matured dry leaf contained essential oil having a composition similar to that of seed oil (Thappa et al., 2003). High... 

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