Biologically active materials Bioactive

Project A involves the synthesis of novel biologically active materials for testing in the preservation of the latex used in the manufacture of paint. From past experience, it is known that the chemicals that are likely to be active in this environment will be those based on heterocycles containing sulphur. Therefore for this Project the particular Skill Requirement is the ability to design and synthesise sulphur-containing heterocycles that will show bioactivity in this industrial outlet. The two people who will be required for this task are available in the cur-... 

This subject can be considered in terms of five different types of molecules or materials (a) biologically inert, water-insoluble polymers (b) water-insoluble polymers that bear biologically active surface groups (c) water-swellable polymeric gels, or amphiphilic polymers that function as membranes (d) water-insoluble but bioerodable polymers that erode in aqueous media with concurrent release of a linked or entrapped bioactive molecule and (e) water-soluble polymers that bear bioactive agents as side groups. 

Research of biologically active silicone materials continues. The synthesis and characterization of polysiloxanes having bioactive pendant groups,556 557 and the preparation of bioactive porous organic-inorganic hybrids for medical applications,558 have been reported. 

The collection procedure itself is straightforward. After cataloguing and identification, 1-2 kg of the plant material is dried, or stored in alcohol and brought back to the lab. The plant material is crushed and extracted with various solvents (most plant-derived bioactive molecules are low molecular mass substances, soluble in organic solvents of varying polarity). After removal of the solvent, the extracts are screened for desirable biological activities (e.g. inhibition of microbial growth, selective toxicity towards various human cancer cell lines, etc.). 

Great amount of marine fish species have been identified with potential nutraceutical and medicinal values. Consequently, a number of bioactive compounds have been identified including fish muscle proteins, peptides, collagen and gelatin, fish oil, fish bone. Bioactive peptides derived from various fish muscle proteins have shown various biological activities including antihypertensive, antibacterial, anticoagulant, anti-inflammatory, and antioxidant activities, and hence they may be a potential material for biomedical and... 

Once it was established that pheromone biosynthesis was regulated by a peptide produced in the SEG, the next goal was to identify the peptide. In the purification of any biologically active factor, each purification step requires a sensitive bioassay to measure the active material. In the purification of PBAN, the bioassay consisted of head ligated females that were injected with bioactive fractions. After a 1-3 h period of incubation, the pheromone gland was excised and titers of pheromone determined by gas chromatography (GC). The first PBAN was purified and identified from H. zea (Raina el ah, 1989). Dissection of about 5000 brain-SEG complexes followed by several steps of HPLC purification resulted in a pure peptide that could be sequenced. It was found to be a 33 amino acid peptide with a C-terminal amide (Table 5.1). The peptide was synthesized and was shown to be active in the bioassay in a dose as low as 2 pmol (Raina et al., 1989). In the same year, a PBAN from B. mori was purified and sequenced (Kitamura et al.,... 

Chemical fractionation of whole products and by-products from synthetic fuel production affords a logical first step in the evaluation of these materials for biological activity and the subsequent prediction of health hazards. Aliphatic and aromatic hydrocarbons, along with smaller amounts of heteroatomic species, constitute the bulk of all crude product materials and define a primary class separation need. Subfractionation of these fractions can lead to identification of bioactive components, Aliphatics are separated from the entire sample by a simple liquid chromatographic elution scheme. Aromatic compounds can be isolated by a cyclo-hexane-dimethylsulfoxide solvent partitioning scheme, A Sephadex LH-20 gel separation scheme appears feasible for the fractionation of crude liquids into aliphatic-aromatic, lipophilic-hydrophilic, polymeric, and hydrogen bonding classes of compounds. 

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