Plants screening

Plants and microorganisms produce unique and diverse chemical stmctures, some of which act as immunomodulators (18—28). Of specimens used in traditional medicine, approximately 450 plant species have shown antiviral activity out of 4000 plants screened (19). Several tannins (20) exhibit strong inhibition of tumor promotion experimentally. Pretreatment of mice with small amounts of tannins for several days strongly rejected transplanted tumors. This activity has been claimed to be effected through enhancement of host-mediated antitumor activity. 

Shahandeh H., Hossner L.R. Plant screening for chromium phytoremediation. Int. J. Phytoremediat 2000 2 31-51. 

McLaughlin, J.L. Crown gall tumours on potato discs and brine shrimp lethality two simple bioassays for higher plant screening and fractionation, in Methods in Plant Biochemistry, Hostettmann, K., Ed., Vol. 6, Academic Press, London, 1-32, 1991. 

Many new microbial compounds with potential blocherbicldal activity have been Isolated, chemically characterized, and a portion of their biological activities determined using various bioassay techniques or by direct plant screening. Some of these compounds are virulence factors of plant pathogens, thus Information on these phytotoxins can benefit the development of microbes as herbicides and potentially provide new chemical herbicides. Data on some of these compounds and their structures are presented. Information on source, biological activity, and possible mode of action (when available) Is briefly summarized. 

Knablein J, McCaman M. Modern Biopharmaceuticals - Recombinant Protein Expression in Transgenic Plants. Screening. Trends Drug Discov., 2003 6 33-35. 

Knablein, J., Biotech A New Era In The New Millennium - Fermentation and Expression of Biopharmaceuticals in Plants. SCREENING - Trends Drug Disc. 2003, 4, 14-16. 

Knablein, J. 2003. Biotech a new era in the new millennium Fermentation and expression of biopharmaceuticals in plants. Screening Trends Drug Discov 4, 14—16. 

Knablein, J., McCaman, M. 2003. Modem biopharmaceuticals — recombinant protein expression in transgenic plants. Screening Trends Drug Discov 6, 33—35. 

In busy avenues, the street dust has a lead content ranging from 500 ppm to 2 500 ppm and plant screens are effective to reduce the lead burden in gardens. Some similar results were obtained in British cities (Davies 1978). 

FIGURE 9.7 PFLP protein could be a selection marker for transgenic plant screening of orchid (Oncidium) plants. The survivability of -transgenic lines (AG2, AG7, AGS, and AGIO) and wild-type (WT) orchid plants could be observed after inoculation of soft rot pathogen. 

The most important criterion for a universal in vitro herbicide prescreen is that an active herbicide not be missed. This is not to say that whole plant screens have not missed active herbicides. 

They lack a cuticle. The cuticular penetration barrier prevents ascertaining whether many new chemical groups are toxic. This barrier can later be overcome by synthesis of analogs of active structures or by better formulation. The knowledge that a chemical is toxic if it reaches the plant cell is probably the most important lead available from cell cultures that whole plant screens lack. The absence of cuticle and short diffusion distances in cell cultures, provide a possibility for performing rapid kinetic. 

IDENTIFICATION OF TOXINS IN PLANT SCREENINGS FOR RESEARCH OR DEVELOPMENT PURPOSES... 

Does this plant screen out aluminium waste ... 

In crushing plants, screens with surfaces comprising usually square apertures (formed by a series of wires extending in two directions) or slots (formed by parallel bars these are known as grizzlies) are used for the following purposes ... 

Specific areas discussed include advantages and uses of the stamen-hair system, review of floral and stamen-hair morphology, cultivation of stock plants, screening of untreated plants for abnormally high aberration rates, preparation and handling of cuttings for experimental use, and consideration of flower production and of statistically acceptable numbers of cuttings and stamens rec[uired for a typical experiment. 

The discovery of taxol originated from a screening programme instituted in 1960 by the US national cancer institute. One of plants screened was the Pacific yew tree Taxus brevifolia where extracts were found to have in vitro qrtotoxic activity against tumour cells. Initially, there was a lack of interest in the compound since it was only found in very small amounts in T. brevifolia but eventually better sources were found in other Taxus species. Figure 21.21 shows the important stmctural features for taxol which contribute to its activity. As with the Vinca... 

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