Antibacterial substances

Murexine and related compounds have marked actions on the nicotine receptor as expected from choline esters (87-89). Toxins from the digestive glands of nudi-branchs have marked effects on the cardiovascular system of the rat (23). Antiviral and antibacterial substances have been obtained from molluscs (90,91). 

SAKANAKA s, KIM M, TANiGUCHi M and YAMAMOTO T (1989) Antibacterial substances in Japanese green tea extract against Streptococcus mutans, a cariogenic bacterium , Agric Biol Chem, 53, 2307-11. 

The history of penicillin, which is produced from molds, is different. Penicillin is a powerful antibacterial substance that came into extensive use during World War II. There still is no known synthetic way of producing penicillin economically. If the pharmaceutical companies had refused to mass-produce this drug by fermentation because they feared it would soon be synthesized, then millions of people would have been deprived of its healing powers, and those who could have obtained it would have spent ten to one hundred times more for it. 

Not all neomycin salts, however, possess advantages such as a reduced toxicity. In fact, the orotic acid(1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidine carboxylic acid) salt was reported to have a greater toxicity than neomycin itself74f75. some uncertainty of this fact is apparent as other authors have reported the two compounds to be of a similar toxicity 6. The salt of neomycin with usnic acid(an antibacterial substance found in lichens) has been reported to have less antibacterial activity than the neomycin used in the preparation of the salt. 

Synthesis of aminopolysaccharides, therefore, is one of the important research areas in the field of functional materials, examples of biorelated polymers, antibacterial substance, and biodegradable polymers as well as materials for drugs and matrices of drug delivery systems. Only a few methods, however, such as ring-opening polymerization and enzymatic polymerization have been available for the precision synthesis of aminopolysaccharides [4,5],... 

A detailed study on the catalytic use of Pd/TPPTS catalyst in aqueous Sonogashira couplings revealed, that it is possible to obtain unsymmetrical diynes with moderate to good yields in aqueous methanol, with Cul as promoter and Et2NH as base (Scheme 6.18) [44]. The same authors describe a short synthesis of Eutypine, which is an antibacterial substance isolated from the culture medium of Eutypa lata. The fungus E. lata is held responsible for a vinyard disease known as eutyposis, so obviously this synthesis is of great interest. 

Before the 1930s bacterial diseases were a major cause of death. Pneumonia and tuberculosis were major killers. Since the advent of the sulfa drugs and penicillins many bacterial diseases have been controlled. The antibacterial drugs will be discussed by type. We will see that some of these are antibiotics, an antibacterial substance produced by a living organism such as a bacterium or fungus, rather than synthesized in the laboratory. 

Penicillin was discovered in 1928 by Alexander Fleming, who noticed that one of his experimental cultures of staphylococcus was contaminated with mold, which caused the bacteria to lyse. Since mold belonged to the family Penicillium, he named the antibacterial substance penicillin. 

Boll, P. M., Lillevik, H. A., Gottshall, R. Y. and Lucas, E. H. 1955. Antibacterial substances in seed plants against tubercle bacilli. III. Solanocapsine, the antibacterial alkaloid of Solanum pseudocapsicum. Antibiotics Annales, 255-259. 

DC026 Gottshall, R. Y., E. H. Lucas, A. Lickfeldt, and ]. M. Roberts. The occurrence of antibacterial substances active against Mycobacterium tuberculosis in seed plants. J Clin Invest 1949 28 920-923. 

Paul Ehrlich demonstrated the effective use of methylene blue in the treatment of malaria. He also synthesized arsenical compounds (neoarsphenamine) effective in the treatment of syphilis. The synthesis of newer and powerful antibacterial substances gave the recognition to Paul Ehrlich as the father of modern chemotherapy and awarded the Nobel prize of medicine in 1909. 

Established in 1947, the Japanese Food Sanitation Law, which describes standards and criteria of foods, was the first essential law in Japan on food safety. According to this law, meat, eggs, milk, dairy products, fish, and shellfish should not contain any antibiotic or synthetic antibacterial substances. 

Gosio discovered mycophenolic acid an antibacterial substance produced by microbes (too toxic for use as antibiotic). 

Nobel prize winner in 1952) and professor at Rutgers University. He was the first to use the term antibiotic to designate the mold produced antibacterial substances discovered by Fleming in 1928. He became the outstanding authority ill tills field. 

Sawada T, Aono M, Asakawa S, Ito A, Awano K (2000) Structure Determination and Total Synthesis of a Novel Antibacterial Substance, AB0022A, Produced by a Cellular Slime Mold. J Antibiotics 53 959... 

Bogdanov, S. (1997). Nature and origin of the antibacterial substances in honey. LWF Food Sci. Technol. 30, 748-753. 

Throughout his career Fleming was intensely interested in naturally occurring antibacterial substances, and penicillin was actually the second antibiotic that he discovered. In 1922 he described the antibacterial properties of lysozyme, a substance found in egg whites, mucus, and tears, which lysed, or dissolved, certain bacteria. Fleming found that lysozyme could turn a thick, milky white suspension of bacteria into a clear solution in a matter of seconds. 

Toure, R., Kheadr, E., Lacroix, C., Maroni, O., and Fliss, I. (2003). Production of antibacterial substances by Bifidobacterial isolates from infant stool active against Listeria moncyto-genes. ]. Appl. Microbiol. 95(5), 1058-1069. 

A related antibacterial substance is nata-mycin, identical to pimaricin. Natamycin is effective in controlling the growth of fungi but has no effect on bacteria or viruses. In fermentation industries, natamycin can be used to control mold or yeast growth. It has a low solubility and therefore can be used as a surface treatment on foods. Natamycin is used in the production of many varieties of cheese. 

Alexander Fleming (1881-1955). He researched for years on antibacterial substances that would not be harmful to humans. His findings on penicillin were made at St Mary s Hospital, London. 

From 1935 to 1939 he worked on snake venoms, tumor metabolism, the mechanism of lysozyme action, and the invention and development of methods for biochemical microanalysis. In 1939 he began a systematic study of antibacterial substances produced by microorganisms and the reinvestigation of penicillin. Later he worked on the isolation and elucidation of the chemical structure of penicillin and other natural antibiotics. 

Cer-O-Cillin [Pfizer]. TM for an antibacterial substance that differs from penicillin G in that the benzyl group is replaced with an allylmercapto-methyl group. In concentrations up to 500,000 units per cc in sterile water for injection, sterile sodium chloride for injection, or sterile 5% dextrose. 

CAS 154-21-2. C18H34N206S. An antibacterial substance produced by Streptomyces lincolnensis. The hydrochloride is stable in the dry state and in aqueous solution for at least 24 months, soluble in water at room temperature in concentrations up to 500 mg/ mL. 

Fleming spent several years investigating the novel antibacterial substance and showed it to have significant antibacterial properties and to be remarkably non-toxic to humans. Unfortunately, the substance was also unstable and Fleming was unable to isolate and purify the compound. He therefore came to the conclusion that penicillin was too unstable to be used clinically. 

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