Wax components

The composition of montan wax depends on the material from which it is extracted, but all contain varying amounts of wax, resin, and asphalt. Black montan wax may be further processed to remove the resins and asphalt, and is known as refined montan wax. White montan wax has been reacted with alcohols to form esters. The wax component of montan is a mixture of long-chain (C24—C q) esters (62—68 wt %), long-chain acids (22—26 wt %), and long-chain alcohols, ketones, and hydrocarbons (7—15 wt %). Cmde montan wax from Germany typically has a melting point of 80°C, an acid number of 32, and a saponification number of 92. 

Knob (southern Canterbury Administrative Region see Fig. 2.11) and cycloartenol methyl ether [58] was found in plants from Clarke River, whereas four other collections failed to yield any TMEs. Similarly, populations of C. rigida (Raoul) Zotov from eastern South Island do not synthesize TMEs, whereas those from western South Island were shown to accumulate p-amyrin methyl ether [59]. An additional difference between populations from these two sites lies in the capacity of the former to produce short-chain wax components, as opposed to long-chain compounds from the latter (Cowlishaw et al., 1983). Different chemodemes were also described for C. cheesemanii (Hackel ex Cheesem.) Zotov plants from North Island exhibited lupeol methyl ether as the dominant compound along with lesser amounts of arun-doin and two unidentified compounds, whereas populations from the South Island had arundoin as the major compound with lesser amounts of lupeol methyl ether. 

Evershed R.P., Heron C., Goad L.J., Epicuticular wax components preserved in potsherds as chemical indicators of leafy vegetables in ancient diets, Antiquity, 1991, 65, 540 544. 

Waxes are biosynthesized by plants (e.g., leaf cuticular coatings) and insects (e.g., beeswax). Their chemical constituents vary with plant or animal type, but are mainly esters made from long-chain alcohols (C22-C34) and fatty acids with even carbon numbers dominant (Fig. 7.11). They may also contain alkanes, secondary alcohols, and ketones. The majority of wax components are fully saturated. The ester in waxes is more resistant to hydrolysis than the ester in triacylglycerols, which makes waxes less vulnerable to degradation, and therefore more likely to survive archaeologically. 

Waxes are found in animal and insect secretions and the cell walls of some bacteria. The stored fat of marine animals has a high wax component which forms an energy reserve. Waxes are extracted and used commercially in the preparation of creams, cosmetics, polishes, lubricants and protective coatings for surfaces. 

Use of carbon tetrachloride to extinguish a wax fire caused an explosion. This was attributed to a violent reaction between unsaturated wax components and carbon tetrachloride initiated by radicals from decomposing peroxides [1], Perhaps a more likely explanation could be that contact of the cold low-boiling liquid with the hot molten wax led to the physical effect of a vapour explosion, rather than the chemical explosion postulated [2],... 

Uses. Solvent for naphthalene, fats, resins, oils alternate for turpentine in lacquers, shoe polishes, and waxes component in motor fuels and lubricants... 

Cutin-Wax Interactions. In order to obtain a more complete structural picture of plant cuticle, 13C CPMAS data were also obtained for the polymeric assembly prior to removal of waxes (Figure 5). A second (CH2)n peak appeared in the spectrum, and additional signal intensity in the carboxyl region produced a single broadened peak. Bulk methylene carbons from cutin and wax components exhibited identical values of Tip(H), indicating that they were mixed intimately and shared a common 1H spin reservoir... 

Ukishima, Y., Masui, T., Matsubara, S., Goto, R., Okada, S., Tsuji, K., and Kosuge, T. (1987). Wax components of escolar (Lepidocybium flavobrunneum) and its application to base of medicine and cosmetics. Yakugaku Zasshi 107, 883-890. 

Within given molecular weight limits, wax components having higher melting points crystallize in plates. Low-melting-point components crystallize in needles. Others crystallize in mal-shaped conformation. This process is independent of the fuel or oil in which the crystals form. 

An example of artificial orientation was the orientation attained in cell walls of cork tissue by compression, which gives rise to orientation of the walls in a plane perpendicular to the direction of pressure. Irradiation with the beam in the plane of orientation resulted in a fibre pattern from which the orientation in the walls of the ali-cyclic wax component (friedelin) could be determined ( ). 

Table 16.1 Wax components from web in Agelenidae (Prouvost et al., 1999) and in Amaurobiidae (Trabalon and Assi-Bessekon, 2008).

Table 16.2 Wax components from cuticle o/Tegenaria sp. (Agelenidae) (Trabalon et al 1996, 1997 Prouvost et al., 1999).

Erosion and wax degradation also occurs in the cuticle of rice in contact with Helminthosporium oryzae germlings (AA) and the fungus produces excessive amounts of an extracellular matrix around germ tubes and appressoria. The extracellular sheath or matrix also was shown to adhere tenaciously to the cuticle and associated wax components. 

Important solvent properties are volatility, viscosity, surface tension, and lipid solubility. The first three determine the area over which a given volume of solvent spreads the larger the area of contact between insecticide and outer cuticle layers, the larger its total penetration rate will be. Acetone does not spread very far from the site of application, because it is so volatile. Lipid solubility affects the dissolution of the wax components of the epicuticle. By disrupting this layer, e.g., depositing a drop of acetone, the insecticide could bypass the epicuticular barrier. All these effects together may explain why an optimal balance of solvent properties is necessary to obtain maximal penetration rates (Welling and Patterson, 1985). 

Neutral Degras. [Fanning] Fatty esters of wool grease lubricant, dasticizer for tvire drawing compds., slushing and cutting oils, rust preventative, adhesives textite inhibits crystallization of wax components. 

These results were interpreted as an indication that the relatively high molecular weight, nonvolatile tobacco wax components were the major precursors in tobacco of the PAHs in smoke, whereas the moderate to low molecular weight and volatile flavorful components in tobacco did not contribute significantly to the PAH levels in smoke. 

Addition of the organic solvent-soluble tobacco components, for example, long-chained aliphatic hydrocarbon fraction, solanesol, or p-sitosterol, to unextracted (control) tobacco increased the levels of the total and some individual PAHs in the CSC. Thus, removal of tobacco wax components reduced the levels of both the total and individual PAHs in CSC, whereas addition of tobacco wax components increased the levels of both the total and individual PAHs in CSC (3251, 3269). 

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