Plants initial extraction

Initial Extraction Technique Continuous extraction apparatus was employed, including an extractor designed to contain the starting plant materials, a distillation flask to hold the solvent mixture, the flask being equipped with a reflux condenser, a drip device to facilitate the removal of the volatilized mixture from the condenser and to percolate it through the continuous extractor, and a Soxhiet type return. Means for heating the continuous extraction system were provided. 

API extracted from plant sources Collection of plants Cutting and initial extraction(s) Introduction of the API Starting Material into process Isolation and purification Physical processing. and packaging... 

Stage of mastitis Plants genera and minerals used to prepare the initial extracts/ solutions for remedies... 

The solubility of these substances in organic solvents facilitates their initial extraction and purification from plant material using, for example, petroleum ether. Subsequent chromatographic fractionation facilitates separation of individual alkaloid components. Many alkaloids are poisonous (and have been used for this purpose), although at lower concentrations they may be useful therapeutic agents. Several of the best known alkaloid-based drugs are discussed below. The chemical structure of most of these is presented in Figure 1.11. 

Traditionally, drug discovery programmes within the pharmaceutical industry relied heavily upon screening various biological specimens for potential drugs. Prior to the 1950s, the vast bulk of drug substances discovered were initially extracted from vascular plants (see also... 

The determination of diazinon in foods is important because this chemical is used as a pesticide on plant crops and, at least in some cases, in pesticide dips for the control of parasitic infestations in animals (Brown et al. 1987 Miyahara et al. 1992). Because animals are exposed to this compound, both via pesticide dips and by ingestion of crops to which diazinon has been applied, some methods have been reported for animal products. The majority of methods, however, deal with the determination of residues in plant products. Most of the analytical methods found that describe the extraction from, and determination of, diazinon residues in various crops (plant materials) were developed as part of multiresidue methods. They are based on homogenization of the sample with an organic solvent (polar or non-polar) the isolation of the residues from this initial extract and, usually, some additional cleanup prior to the analysis of the extract by GC. The most common non-MS modes of detection exploit the... 

Techniques of Purification. The purification techniques have included column and batch adsorption, extraction, dialysis, and column and paper chromatography. Liberal use was made of the fact that the gibberellate anion is not soluble in ethyl acetate, whereas the free acid is soluble, and that charcoal will adsorb GA3 from aqueous solutions but release it with acetone (26). As a rough rule, preliminary concentration by a factor of about 105 was necessary before significant use of paper chromatography could be made. For kudzu vine and pinto bean, a known amount of GA3 was added to an aliquot of the plant extract and taken through the same procedure as the initial extract. These controls are subsequently referred to as "spiked extracts, to differentiate them from the initial or "natural extract. 

For large-scale purification, the Purex Plant solvent extraction bank was used first to separate Am-Cm from the Pu in the target element and then to separate Am-Cm from the A1 in the target element. In each of the four campaigns that have been processed, the Pu in the target element has been purified by the normal Purex flowsheet. In each case, the Am-Cm fraction was initially rejected to the waste (1AW) stream. 

Initially, most of the materials screened were pure compounds of synthetic origin, but the program also recognized that natural products were an excellent source of complex chemicals with a wide variety of biological activities. From 1960 to 1982 over 180,000 microbial-derived, some 16,000 marine organism-derived, and over 114,000 plant-derived extracts were screened for antitumor activity, mainly by the NCI, and, as illustrated above, a... 

Other similar procedures are reported. One reported method11 consisted of the initial extraction from a suspension of aerial plant parts in 12 aqueous NH4OH into toluene and use of benzene-petroleum ether (9 l) saturated with formamide to elute the alumina column. Jovanovics, Szasz et al.12, in a procedure similar to Svoboda s10, extracted the plant parts first with 60 aqueous methanol containing 2 tartaric acid, and then into ethylene dichloride. 

This chapter has four sections that focus on laboratory-scale capture steps solids removal, solvent extraction, solid phase adsorption, and expanded bed adsorption. Although these techniques are widely applicable, most of this chapter is aimed at extraction of microbial fermentation broth. Techniques specific to initial extraction of plants and marine organisms can be found in Chapters 12 and 13, respectively. The first section describes laboratory-scale procedures for batch filtration and centrifugation. The second section describes solvent-extraction procedures with either water-miscible or -immiscible solvents. The third section describes using adsorbents for solid-phase extraction. The fourth section describes a technique known as expanded bed adsorption, which is unique in that it enables resin-column recovery of product directly from unclarified fermentation broth. 

This work is a part of a European research program initiated at the Soultz-sous-Forets site (France) in 1987 which aims to develop a pilot plant for extracting heat accumulated in the deep fractured granitic basement. Heat extraction must be carried out by forced circulating of a fluid between three wells drilled at S km depth. 

Procedures for the extraction of carotenoids from a wide variety of tissues have been reported in the literature. Because of differences in plant materials, no one method can be considered universal. However, the various methods are quite similar in principle. Carotenoids are extracted with an organic solvent such as methanol, ethanol, acetone, hexane, or petroleum ether. These may be used singly or as mixtures of two or more. In some cases, heating has been used to facilitate the extraction, although there is some risk in this as noted above. Grinding or blending has been used with some tissues, and in some cases this has been carried out with the solvent directly. When extracting fresh tissue, the initial extraction must be carried out with a water-miscible solvent such as acetone, methanol, or ethanol. Specific examples of procedures for various tissues are discussed in the review by Davies (1976). 

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