Fujian Huitian Biological Pharmacy Co., Ltd.

Trimethoprim (TMP) is an antibacterial agent, a lipophilic weak base, and its chemical structure belongs to the pyrimethamine class. It has antibacterial activity against Escherichia coli, Klebsiella, Proteus mirabilis, Salmonella, and Shigella, but has no obvious antibacterial effect on Streptococcus pneumoniae, Neisseria gonorrhoeae, and Neisseria meningitidis, and has no effect on Pseudomonas aeruginosa. The mechanism of action of this product is to interfere with bacterial folic acid metabolism. It mainly selectively inhibits the activity of bacterial dihydrofolate reductase, so that dihydrofolate cannot be reduced to tetrahydrofolate, and synthetic folic acid is the main component of nucleic acid biosynthesis. Therefore, this product prevents the synthesis of bacterial nucleic acids and proteins, and the binding of this product to bacterial dihydrofolate reductase is 50,000 to 60,000 times tighter than that to mammalian enzymes. The combination of this product and sulfonamides can double block the bacterial folic acid synthesis metabolism, have a synergistic effect, enhance the antibacterial activity of sulfonamides, and convert the antibacterial effect into a bactericidal effect, reducing the production of drug-resistant strains.

Aminoglycoside antibiotics have good antibacterial effects on various Gram-negative and Gram-positive bacteria, and inhibit bacterial protein synthesis by binding to the bacterial ribosome 30S subunit.

Aminoglycoside antibiotics have good antibacterial effects on various Gram-negative and Gram-positive bacteria. The mechanism of action is to bind to the 30S subunit of the bacterial ribosome and inhibit the synthesis of bacterial proteins. In recent years, the number of Gram-negative bacteria resistant to gentamicin has increased significantly.

Kanamycin sulfate is an aminoglycoside antibiotic. It has good antibacterial effects on most Enterobacteriaceae such as Escherichia coli, Klebsiella, Enterobacter, Proteus, Shigella, Salmonella, Citrobacter, Providencia, Yersinia, etc.; influenza bacillus, Brucella, meningococci, gonococci, etc. are also mostly sensitive to this product. Kanamycin also has a certain effect on Staphylococcus (methicillin-sensitive strains) and Mycobacterium tuberculosis, but is ineffective against Pseudomonas aeruginosa. Other Gram-positive bacteria such as hemolytic streptococci, Streptococcus pneumoniae, Enterococcus and anaerobic bacteria are mostly resistant to this product. This product mainly binds to the 30S subunit of the bacterial ribosome and inhibits bacterial protein synthesis. In recent years, the number of resistant strains has increased significantly, because some bacteria produce aminoglycoside inactivating enzymes, which make them lose their antibacterial activity. Kanamycin has complete cross-resistance with streptomycin and neomycin, and may have partial cross-resistance with other aminoglycosides.

This product has a broad-spectrum antimicrobial effect in vitro, including aerobic Gram-negative and Gram-positive bacteria, anaerobes, Rickettsia, spirochetes and Chlamydia. It has bactericidal effects on the following bacteria: influenza bacillus, Streptococcus pneumoniae and Neisseria meningitidis. It only has antibacterial effects on the following bacteria: Staphylococcus aureus, Streptococcus pyogenes, Streptococcus viridans, group B hemolytic Streptococcus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella typhi, Salmonella paratyphi, Shigella, Bacteroides fragilis and other anaerobic bacteria. The following bacteria are usually resistant to chloramphenicol: Pseudomonas aeruginosa, Acinetobacter, Enterobacter, Serratia marcescens, indole-positive Proteus, methicillin-resistant Staphylococcus and Enterococcus. This product is an antibacterial agent. Chloramphenicol is fat-soluble and enters bacterial cells by diffusion, and reversibly binds to the 50S subunit of the bacterial ribosome, which blocks the growth of the peptide chain (possibly due to the inhibition of the action of transpeptidase), thereby inhibiting the formation of peptide chains and preventing protein synthesis.