Acids, organic terpene derived

A considerable number of mycotoxins that show high toxicity to vertebrates and/ or invertebrates are produced by organisms associated with crop plants (Flannigan 1991). There are many known cases of human poisoning caused by such compounds. There are three broad categories of mycotoxins represented here, based on the structures of the intermediates from which these secondary metabolites are derived. They are (1) compounds derived from polyketides, (2) terpenes derived from mevalonic acid, and (3) cyclic peptides and derivatives thereof. 

The term lipid is frequently used to denote a wide variety of natural products fatty , oily or waxy substances of animal and vegetable origin that are easily soluble in organic solvents readily satisfy this loose definition. Thus, such diverse compounds as fatty acids and their derivatives, triglycerides, sterols, phosphatides and sphingolipids, carotenoids, bile acids, vitamins A, D, E, and K, long-chain alcohols, terpenes, etc., may be included. Studies of these substances by GC are indeed numerous a comprehensive survey of this field is beyond the scope of this... 

Christie (2) noted that a variety of diverse eompounds generally soluble in organic solvents are usually classified as lipids, i.e., fatty acids and their derivatives, steroids, terpenes, carotenoids, and bile acids. He suggested that many of these diverse compounds have little in the way of structure or function to make them related, and that many substances regarded as lipids may be more soluble in water, e.g., glycolipids, gangliosides, than in organic solvents. Table 1 provides a list of diverse lipophilic substances that have been examined by TLC. It includes typical sorbents, solvent systems, and references for these lipophilic substances. 

Classical organic chemistry provides a wide variety of potential analytes for electron ionization, the only limitation being that the analyte should be accessible to evaporation or sublimation without significant thermal decomposition. These requirements are usually met by saturated and unsaturated aliphatic and aromatic hydrocarbons and their derivatives such as halides, ethers, acids, esters, amines, amides etc. Heterocycles generally yield useful El spectra, and flavones, steroids, terpenes and comparable compounds can successfully be analyzed by El, too. Therefore, El represents the standard method for such kind of samples. 

Organic aerosols formed by gas-phase photochemical reactions of hydrocarbons, ozone, and nitrogen oxides have been identified recently in both urban and rural atmospheres. Aliphatic organic nitrates, such dicarboxylic acids as adipic and glutaric acids, carboxylic acids derived from aromatic hydrocarbons (benzoic and phenylacetic acids) and from terpenes emitted by vegetation, such as pinonic acid from a pinene, have been identified. The most important contribution in this held has been that of Schuetzle et al., who used computer-controlled... 

The term lipid includes all compounds that release fatty acids on digestion, so that this definition is more extensive than that of fat. Compounds which are insoluble in water, soluble in organic solvents but not derived from fatty acids have been termed non-saponifiable lipids. They include steroids, terpenes and ubiquinone. 

Organic components of polishes are widespread. Thus most products emit complex VOC mixtures that may consist of alkanes, various alcohols, acetates, C2-C4-benzenes, terpenes and derivatives of naphthalene. This is illustrated by the range of compounds emitted by a furniture polish (Figure 15.2b) and a shoe polish (Figure 15.2c). Many modern floor waxes are based on natural ingredients like alkyd resins. On oxidative degradation of unsaturated fatty acids, volatile aliphatic aldehydes (C5-C11) with unpleasant smell (Ruth, 1986) are formed and the emission rates may remain at high levels over months and even years (Salthammer, 1999). 

During the early stages of our bee biomonitoring project, we chemically profiled each component that was used in the construction of our instrumented hive condos (Table 2.4). Unpainted pine boards were rich in terpene peaks. In fact, using artificial neural networks, we were often able to identify from which hive a sample came, based heavily on their individual terpene fingerprints [112, 113]. Vinyl screens gave rise to several ethers. Polyethylene parts released various aromatic and aliphatic derivatives. The application of white paint to the exterior surfaces of hive boxes added some organic acids, alcohols, and additional hydrocarbons to the hive environment. 

Plant essential oils are the low molecular weight volatile mixtures, biosynthesized in various plant organs. The chemical nature of essential oils belongs to the composition of terpene compounds (mono-, sesqui-, and diterpenes), which are mainly obtained as hydrocarbon compounds or the derivatives of oxygen molecule. A few components of the essential oil are nitrogenous or sulfury in nature which are found as alcohols, acids, esters, epoxides, aldehydes, ketones, amines, and... 

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