Aloe species components

Although A. vera sa.dA.ferox species are the most important commercial in the international markets, it is largely the presence of anthrones and polysaccharides content that determine the plants effectiveness for therapeutic activity. There are other Aloe species that could be promoted for similar purposes when those species contain one or both groups of bioactive compounds. The biological activities of the Aloe sp could be attributed to synergic actions of the components rather than from a single component 16). 

The family, characteristic of Arabia and South Africa with some species in other parts of Africa and Madagascar, has been separated from the Liliaceac. Species have been introduced elsewhere. Several have been used as a source of laxative anthraquinones and as a component of cosmetic preparations. Aloe is one of the oldest drugs. 

The genus Aloe from Africa is highly diverse with hundreds of species, however, only a minor number of these diversity has been explored in search for new bioactive components. Mat r of them are being use extensively by traditional healers, suggesting that the genus can be the source of potential new compounds that are waiting to be discovered or commercialized. A. vera and. ferox are two popular and well species that contain many unique constituents with biological activity and with application to the pharmaceutical, cosmetic, personal care products sectors as well as to the continued uses in traditional medicines. 

Rhodium supported on y-ALOs is an important component of 3-way automotive catalysts and has been studied by a wide variety of methods [1-5] including ESR. In the last 15 years Rh-species introduced into zeolites of different types (Y, X, L, A, SAPO) have also been examined by several techniques [6-9]. However, most of these methods were applied after the specimens were removed from actual reaction conditions and transferred into the respective characterization instruments and the state or behavior of the catalyst in-situ was arrived at indirectly by inference. Also the deactivation processes or the effect of modifiers is seldom, if ever, determined by direct in-situ observations. We have previously devised a method for high-temperature measurement of ESR-active ions under flow conditions and applied it to characterize specimens containing Cu [10] or Cr " [11]. We have extended this method now to specimens containing Rh. Here, we summarize the results of a study of the interaction of Rh/y-ALOB and Rh/ZSM-5 with different gases and gas mixtures (NO, NO2, CO, propene, O2, H2O) at 120-573 °K. The amount of Rh present in the samples is evaluated quantitatively. The effect of copper and lanthanide addition on the stabilization of by the zeolitic matrix was also investigated. 

Although the alkaloids coniine (48) and y-coniceine (51) bear a structural resemblance to the piperidine alkaloids, these compounds are derived from a polyketide pathway (Fig. 29.17). Lysine is a poor precursor, and early attempts to show incorporation of this compound resulted in failure. Acetate is a much better precursor. Coniine is a highly toxic alkaloid and is one of the toxic components of poison hemlock (Conium maculatum, Apiaceae) (Cutler, 1992). Otherwise, alkaloids are very uncommon in the Apiaceae. Coniine does occur in several other plants, for example, Sarracenia (Sarracenia). y-Coniceine is found in several species of Aloe (Liliaceae) (Dring et al., 1984). Coniine is toxic to the aquatic plant Lemna (Wink, 1993). The LDioo p.o. in the... 

Aloe-emodin - l,8-dihydroxy-3-(hydroxymethyl)-9,10-anthra-cenedione - is a component found in the latex of various species of aloe iq.v.) used to prepare the pigment known as aloe brown. It is also found in the roots of various Rehum species as well as in the stamens of Cassia species Merck Index, 1996). 

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