P-Myrcene

In archaeological findings the occurrence of a high abundance of 28-norolean-17-en-3-one has been correlated to smouldering or burning processes undergone by Pistacia resins [94,123,124]. Mastic also contains a polymeric fraction (15 20%) identified as cw-1,4-poly-p-myrcene [128]. 

K.J. van der Berg, J. ven der Horst, J.J. Boon, 0.0. Sudmeijer, Cis 1,4 poly P myrcene the structure of the polymeric fraction of mastic resin (Pistacia lentiscus) elucidated, Tetrahedron... 

Sampling time 60 min extraction temperature 80°C. Monoterpenes a-pinene, p-myrcene, a-phellandreneand limonene sesquiterpenes a-cubebene, a-copaene, p-elemene, p-caryophyllene, a-humulene, y-muurolene, p-eudesmene and caryophyllene oxide diterpenes cembrene A and isoincensole acetate. 

The essential oil is a pale yellowish green with a sweet, sharp refreshing citrus odour. Its chemical composition is very high in the monoterpene limonene (85-98%) with other monoterpenes P-myrcene (1.2-1.7%),... 

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-... 

Both an aqueous phase and an oily phase (including waxes and essential oils) were extracted from the herbs. These were collected separately as described in the next section. The essential oils in the oily extract were camphor, verbenone, P-myrcene, 1,8 cineole and limonene for Rosemary and thymol, geraniol and geranyl acetate,carvocrol and borneol for Thyme. 

C1 p-Myrcene C2 a-Myrcene C3 (Z)-a-Ocimene C4 (E>a-Ocimene C5 (Z)-p-Ocimene C6 (E)-p-Ocimene... 

Floral volatiles could play many roles instead of or in addition to pollinator attraction. For example, many terpenes, including P-myrcene, ( )-P-ocimene, linalool, and ( )-P-caryophyllene, react readily with ozone and other reactive oxygen species (27). Thus, floral volatiles could function to protect the reproductive organs from oxidative damage. A variety of monoterpenes and sesquiterpenes is reported to have antimicrobial activity (28). Hence, floral terpenes could help defend floral organs, like the moist stigma, from bacterial or fungal infection. 

A grouping of the compounds showed that aldehydes and terpenoids, respectively, made up 41-57% and 6-21% of the volatiles in root tissue, 19-24% and 46-58% of leaf volatiles and 6-14% and 81-91% of the stem volatiles (Mazza and Cottrell, 1999). P-Myrcene was the predominant aerial part volatile among Echinacea species (Table 8.4), but in roots, it was found only in E. pallida. An ethanol extract of the achene followed by steam distillation resulted in a P-myrcene content of 6.8% and... 

The photo-NOCAS process has also been reported with P-myrcene (57) as the reactant. The resultant radical cation, generated using dicyanobenzene as the sensitiser, affords the five products (58-62) shown and cyclization within the myrcene radical cation is an essential feature of this reaction sequence. SET photochemistry of aliphatic electron donors can provide a source of radicals. Thus irradiation of donors such as (63), (64), (65) and (66) results in bond fission and the formation of alkyl radicals which undergo addition to alkenes e.g. 67) or alkynes e.g. 68) to give the adducts (69) and (70), respectively. ... 

Figure 4. Cardamom 1 - a- pinene, 2 - sabinene, 3 - P-myrcene, 4 - 1,8-cineole, 5 - y-terpinene, 6 - a-terpinolene, 7 - 4-terpineol, 8 - terpinyl acetate.

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