Streptomycin antimicrobial activity

In 1939 the isolation of a mixture of microbial products named tyrotbricin from a soil bacillus was described. Further investigation showed this material to be a mixture of gramicidin and tyrocidine. In rapid succession the isolation of actinomycin (1940), streptothricin (1942), streptomycin (1943), and neomycin (1949), produced by Streptomjces were reported and in 1942 the word antibiotic was introduced. Chloramphenicol, the first of the so-called broad spectmm antibiotics having a wide range of antimicrobial activity, was discovered in 1947. Aureomycin, the first member of the commercially important tetracycline antibiotics, was discovered in 1948. 

Tetracyclines are a family of antibiotics which display a characteristic 4-fused-core ring structure (Figure 1.16). They exhibit broad antimicrobial activity and induce their effect by inhibiting protein synthesis in sensitive microorganisms. Chlortetracycline was the first member of this family to be discovered (in 1948). Penicillin G and streptomycin were the only antibiotics in use at that time, and chlortetracycline was the first antibiotic employed therapeutically that retained its antimicrobial properties upon oral administration. Since then, a number of additional tetracyclines have been discovered (all produced by various strains of Streptomyces), and a variety of semi-synthetic derivatives have also been prepared (Table 1.18). 

Published studies on the effect of storage and cooking on aminoglycoside residues are limited to streptomycin and neomycin. In most studies, streptomycin was shown to be fairly resistant to storage. No measurable loss of the antimicrobial activity of streptomycin residues in meat was observed after storage at either 4 C or 18 C for 14 days (1, 2). 

Cooking can cause some loss of the antimicrobial activity of streptomycin and neomycin, the loss being dependent on both the temperature and the matrix. When milk and water matrices were heated at 100 C for 30 min, the microbiological inactivation of neomycin was determined at 25% and 35%, respectively. 

Little or no loss of antimicrobial activity was further observed after fermentation of raw sausages containing streptomycin (6). However, smoking/scalding processes could cause a 32-45% reduction of the streptomycin activity (7). When semi- or fully preserved sausages were heated at 90-95 C for 1 h, the microbiological activity of the contained streptomycin exhibited a 50% reduction of the initial dose (8) however, some of the initial activity could be demonstrated in the juices exuded from the heated sausages even when the temperature was raised to 120-125 C. 

Resistance to streptomycin. Streptomycin [209] is produced by Strep-tomyces griseus. It is a tri-acidic base consisting of three components streptidine, streptose and N-methylglucosamine (Figure 7. II). The compound has a broad spectrum of antimicrobial activity, including Ps. aeruginosa (Table 7.13). 

The fact deserves mention that the antimicrobial activity of the samples is lower at Bio/Str ratio of 1/2 than at Bio/Str of 1/1, where an increasing amount of coupled streptomycin is noticed. 

Ross SA, Milner JA (2007) Garhc the mystical food in health promotion. In WUdman REC (ed) Handbook of neutraceuticals and functional foods, 2nd edn. CRC Press, Boca Raton Saavedra MJ, Borges A, Dias C, Aires A, Bennett RN, Rosa ES, Simoes M (2010) Antimicrobial activity of phenolics and glucosinolate hydrolysis products and their synergy with streptomycin against pathogenic bacteria. Med Chem 6 174-183... 

Carbenicillin has a broader range of antimicrobial activity than any other known penicillin. It is not absorbed orally and must be given by injection. Carbenicillin is synergistic with gentamicin colistin and streptomycin. ... 

Kanamycin A is similar to streptomycin and neomycines and has a broad spectrum of antimicrobial action. It is active with respect to most Gram-positive as well as Gram-negative microorganisms (staphylococci, gastric bacilli, rabbit fever, Fridlender s bacillus, proteus, shigella, salmonella). 

Streptomycin is used for the treatment of certain unusual infections usually in combination with other antimicrobial agents. Because it is less active than other members of the class against aerobic gram-negative rods, it has fallen into disuse. Streptomycin may be administered by deep intramuscular injection or intravenously. The dose of streptomycin is 15 mg/kg/day for patients with creatinine clearances above 80 mL/min. It typically is administered as a 1000-mg single daily dose or 500 mg twice daily. The daily dose should be reduced in proportion to creatinine clearance for creatinine clearances >30 mL/min (Table 45-1). 

Synthesis of new l,10-diethoxy-l//-pyrano[3, 3]quinolines and their antimicrobial studies were reported by Dhanabal et al. [27]. All the compounds exhibited moderate antibacterial activity. Interestingly the compound 6-methoxy substituted pyranoquinoline showed better activity than the standard Streptomycin in case of Escherichia coli. 

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