Plant compounds, camphor

Camphor" is the common name for Cinnamomum camphora and the name of the compound that gives this plant its distinctive smell. The compound camphor is frequently used in topical personal care products. The compound camphor comprises approximately 50% of camphor essential oil (Stubbs et al. 2004). 

The isoprene unit exists extensively in nature. It is found in terpenes, camphors, diterpenes (eg, abietic acid), vitamins A and K, chlorophyll, and other compounds isolated from animal and plant materials. The correct stmctural formula for isoprene was first proposed in 1884 (7). 

Perhaps the most interesting arthropodan defensive compounds from the point of view of structural diversity are the alkaloids. While alkaloids had long been believed to arise only as a consequence of plant secondary metabolism, it has become apparent over the last few decades that arthropods are both prolific and innovative alkaloid chemists. The millipede Polyzonium rosalbum, once thought to secrete camphor (20), in fact gives off a camphoraceous/earthy aroma produced by the spirocyclic isoprenoid imine polyzonimine (21). 

Synthetic camphor, 24 540 Synthetic compounds, as plant growth regulators, 13 39-56 Synthetic crude oil, 13 640 Synthetic cyclic molecules, 24 35 Synthetic diamond, 3 530-543 catalyzed synthesis, 3 531-535 crystal growth, 3 535 crystal morphology, 3 534-535 crystal structure, 3 537-538 direct graphite-to-diamond process, 3 535-538... 

Isoprene metabolism in plants is very complex. Plants can synthesize many types of aromatic substances and volatile oils from isoprenoids. Examples include menthol (1= 2 ), camphor (1 = 2), and citronellal (1 = 2). These Cio compounds are also called monoterpenes. Similarly, compounds consisting of three isoprene units (1 = 3) are termed sesquiterpenes, and the steroids (1 = 6) are called triterpenes. 

Monoterpenes, 10-carbon-containing terpenoids, are composed of two isoprene units, and found abundantly in plants, e.g. (+)-limonene from lemon oil, and (—)-linalool from rose oil. Many monoterpenes are the constituents of plant volatile oils or essential oils. These compounds are particularly important as flavouring agents in pharmaceutical, confectionery and perfume products. However, a number of monoterpenes show various types of bioactivity and are used in medicinal preparations. For example, camphor is used in liniments against rheumatic pain, menthol is used in ointments and liniments as a remedy against itching, bitter-orange peel is used as an aromatic bitter tonic and as a remedy for poor appetite and thymol and carvacrol are used in bactericidal preparations. 

The odor of a freshly crushed mint leaf, like many plant odors, is due to the presence in the plant of volatile C10 and Ci5 compounds, which are called terpenes. Isolation of these substances from the various parts of plants, even from the wood in some cases, by steam distillation or ether extraction gives what are known as essential oils. These are widely used in perfumery, as food flavorings and medicines, and as solvents. Among the typical essential oils are those obtained from cloves, roses, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, cedar, and turpentine. Such substances are of interest to us here because, as was pointed out by Wallach in 1887 and reemphasized by Ruzicka in 1935, the components of the essential oils can be regarded as derived from isoprene ... 

Terpenes were originally named after turpentine, the volatile oil from pine trees used in oil painting, whose major constituent is a-pinene. The term was rather vaguely used for all the volatile oily compounds, insoluble in water and usually with resiny smells from plants. The oils distilled from plants, which often contain perfumery or flavouring materials, are called essential oils and these too contain terpenes. Examples include camphor from the camphor tree, used to preserve clothes from moths, humulene from hops, which helps to give beer its flavour, and phytol, found in many plants. 

Oregano Origanum virens L. is an perennial herb with 40-70 cm high and very aromatic. This plant grows in open and dry countries, at altitudes lower than 500-700 m. The major components of essential oil from Origanum virens L. are terpineol, a-pinene, camphor, thymol, carvacrol and cineole. Compounds such as alcohols and dipentene are also present. 

Tliis study describes the isolation and bioassay against insects of six compounds from the Peruvian plant Alchornea trlplinervia. The compounds anthranilic acid, cinnamic acid, and camphor showed significant inhibition of the growth of the tobacco budworm. Anthranilic acid, gentisic acid, senecioic acid, cinnamic acid, and cinnamaldehyde demonstrated low to moderate activity in the boll weevil antifeedant bioassay. Cinnamaldehyde, a constituent of the spice cinnamon, showed the highest level of inhibition to boll weevil feeding. 

Figure 5.1 Examples of terpenoids that are of commercial importance or whose functional role in plants has recently been investigated. Isoprene may stabilize membranes at high temperatures. Camphor, artemisinin and paclitaxel (taxol) are valuable pharmaceuticals. The other three compounds appear to be involved in plant defence pulegone is toxic to herbivores polygodial is a herbivore feeding deterrent and (3 )-4,8-dimethyl-1,3,7-nonatriene, a Cn homoterpene, functions to attract herbivore enemies to herbivore-damaged plants.

Artemisia vulgaris (common wormwood) contains the toxic lactone, santonin, which was formerly used as an antihelminthic drug, but has now been superseded by other less toxic compounds. Depending on the origin of the plant, 1,8-cineole, camphor, hnalool, and thujone may all be major components. Allergic skin reactions (12) and abortive activity have been described. 

Terpenes are are a class of compounds whose chemical structures are based on a number of isoprene units , derived from the hydrocarbon CH2=C(CH3)-CH=CH2 they may themselves be hydrocarbons, but may also contain alcohol (OH), aldehyde/ketone (CO) and carboxylic acid (COOH) groups. Monoterpenes are Cm compounds derived from two isoprene units, sesquiterpenes (Cu) are derived from three isoprene units, diterpenes (C20) from four and tritepenes (C30) from six. Terpenes are widespread in plants, where they are largely responsible for the odor, and they are the major constituents of plant-derived essential oUs . Among the best known terpenes are 3-pinene (turpentine), camphor, menthol and citroneUal (aU monoterpenes) and farnesol (a sesquiterpene that is a constituent of the essential oils of many plants). Certain terpenes have important biological roles vitamin A, for example, is a diterpene, and steroid hormones have a structure related to triterpenes (and are biosynthesized by a similar route). 

An example of a DHS application is the determination of aroma-active compounds in bambuu shoots. In this study, compoimds such as p-cresol, methional, 2-heptanoI, acetic acid, ( ,Z)-2,6-nonadienal, linalool, phenyl acetaldehyde, were extracted from the bambuu shoot samples and analysed by GC. The required sample amount was 10 g, and the extraction temperature was 60°C, using a 30 min extraction time. The stripped analytes were first trapped into a cooled adsorbent tube (VOCARB 3000, at 0 °C), and then thermally desorbed to GC. In DTD, the sample amount required for the analysis is typically smaller than in solid head-space (SHS). In the determination volatile components such as camphor, 1,8-cineoIe and 2,3,S,S-tetramethyl-4-methylene-2-cyclopenten-l-one, from Lavandula luisieri, only 10-20 mg of (dry) plant sample was required for the analysis. The volatiles were desorbed fi om the sample under a helium flow and then cryofocused on a Tenax TA trap at -30 °C. The trap was then quickly heated and the desorbed volatiles were transferred directly to the GC column through a heated fused-silica line (85). 

Among typical organic compounds found in Nature are marsh gas and all the constituents of natural petroleums acetic, lactic, tartaric, benzoic, and a very large number of other acids carbohydrates, including sugars, starches, and celluloses the constituents of plant and animal fats, and waxes the proteins organic bases, such as quinine, strychnine, and other alkaloids indigo, alizarin, and other natural dyes camphor, citral, and other constituents of the... 

Phytochemistry The plant contains tanshinones (Sairafianpour et al. 2001). Water-distiUed essential oils from leaves collected in Arslonbob (Kyrgyzystan) contained cineole, pinene, epi-13-manool, bomyl acetate, camphene, camphor, caryo-phyllene, caryophyUene oxide, humulene, caryophylladienol, bomeol, and other compounds (Basher et al. 1997). 

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