Plant-derived pharmaceuticals, commercial

Plant derived pharmaceuticals are estimated to have an annual value of 9 billion in the U.S. alone (4). Flavors and fragrances have a current worldwide market of about 1.5 billion. Market data for insecticides and other fine chemicals such as pigments are not readily available. The first example, and the only current commercial process based on plant cell culture, is for the production of shikonin in Japan. This compound is both used in medicine and as a pigment (5-7. ... 

Commercialization of Plant-Derived Natural Products as Pharmaceuticals A View from the Trenches... 

A reading of the preceding series of news items and articles indicates that the investigations are mostly limited to synthetic chemicals rather than plant-derived substances, with pharmaceutical companies being heavily involved. However, if biotechnology is a business proposition, it is nevertheless a risky one. The statistic is supplied that for 1400 biotechnology companies located in North America, fewer that 50 products have been successfully commercialized. The quote is added that biotech is one of the worst investments on the street. ... 

One possible alternative production method is through chemical synthesis. Examples of the total chemical synthesis of many natural, plant-derived anticancer drugs have been reported in the literature [3-6]. However, in terms of commercial production, the total chemical synthesis is still not economical and sustainable, mainly because it involves many reaction steps, uses harsh solvents, and usually ends up with a low yield of the target product that is often mixed with various structurally similar byproducts. Instead, semi-chemical synthesis procedures are favored for generating derivatives that present better pharmaceutical properties from either extracted natural products or metabolic intermediates [7]. 

It is important to emphasize that conversion of plant-derived starting materials into chemical products must ultimately lead to industrial-scale processes that yield chemical products at a manufacturing cost that is competitive with their current production from petroleum-derived carbon. Ultrafine chemicals and smaller-volume fine chemicals provide an invaluable proving ground for such activities. Because of the inherent value-added nature of these chemicals, the fundamentals of yield and titer considerations can be elaborated and then scaled up to syntheses commercially practiced by the pharmaceutical and fiavor and fragrance industries. The lessons learned will be critical to the large-scale, microbe-catalyzed conversions needed for cost-effective manufacture of pseudocommodity and commodity chemicals from plant-derived feedstocks. 

M.F. Balandrin, Commercial utilizatitm of plant-derived saponins an overview of medicinal, pharmaceutical and industrial applicatitm, in G.R. Waller, K. Yamasaki (Eds.), Saponins Used in Traditional and Modem Medicine, Plennm Press, New York, 1996, pp. 1-14. 

The classical techniques for the solvent extraction of chemical compounds from vegetable material are based upon the correct choice of solvent and conditions e. g. heating or agitation. A range of commercially important pharmaceuticals, flavours and colourants are now derived from vegetable sources. It has been shown that the solvent extraction of organic compounds contained within the body of plants and seeds is significantly improved by the use of power ultrasound [25]. 

To summarise the arguments, the majority of NPs foimd in plants and microbes are unlikely to possess potent biological activity and even less likely to contain specific, potent biological activity that could be usefully exploited for pharmaceutical use. Furthermore, even when a naturally derived chemical is found to give a good lead, the chemical complexity so characteristic of NPs may make commercial production expensive or impossible. It is surely significant that culturable microbes have been so important as producers of NPs of pharmaceutical value to humans because they can be selected to overproduce complex molecules that humans would find impossible to make. 

Determining the molecular sites of action of bioactive medicinal plant constituents is clearly important for establishing the chemical and physiological basis for herbal medicinal efficacy, for quality control of commercial herbal preparations and for the discovery of lead compounds for synthetic (or semi-synthetic) pharmaceutical development. Of course, it must be recognized that medicinal plant efficacy may derive from complex synergistic effects or even from quasi-placebo effects connected with the taste, mild effects and appearance of the preparation. While recognizing these possible holistic complications, in order to find out how such preparations work, it is clearly important to initially isolate, structurally characterize and define the biochemical targets of plant bioactive substances. 

Enzymes used in food processing are often called commercial enzymes and may be derived from plant, animal or microbial sources. These enzymes are produced in large quantities and are not highly refined. In contrast, the highly refined enzymes produced for pharmaceutical or research purposes, are often crystalline enzymes sold in milligram and gram quantifies by firms that are specialised in fine chemicals . 

Many clinically important pharmaceuticals and initial drug candidates are derived from natural sources such as microbes and plants (96). In most cases, the structural complexity of these drugs precludes chemical synthesis as a practical approach to commercially produce them. This consequently contributes to the dearth of derivatives of these compounds for evaluation as potential drug candidates. Also, slow generation time and low quantities of the drugs from their natural producers are usually major obstacles to contend with. 

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