Which of the following antimicrobial drugs is synthetic?

• A. Vancomycin
• B. Streptomycin
• C. Ciprofloxacin
• D. Penicillin G

Answer: (C)

Verified step by step guidance

1. Understand the difference between natural, semi-synthetic, and synthetic antimicrobial drugs. Natural antibiotics are directly produced by microorganisms, semi-synthetic antibiotics are chemically modified natural antibiotics, and synthetic antibiotics are completely man-made through chemical synthesis.
2. Identify the origin of each drug listed: Vancomycin is a natural antibiotic produced by the bacterium Amycolatopsis; Streptomycin is a natural antibiotic produced by Streptomyces griseus; Penicillin G is a natural antibiotic produced by the mold Penicillium notatum.
3. Recognize that Ciprofloxacin is a synthetic antimicrobial drug, belonging to the fluoroquinolone class, which is chemically synthesized in the laboratory rather than extracted from natural sources.
4. Confirm that Ciprofloxacin is synthetic by noting that it does not originate from a microorganism but is designed and produced through chemical processes to target bacterial DNA gyrase and topoisomerase IV.
5. Conclude that among the options, Ciprofloxacin is the synthetic antimicrobial drug, while the others are natural antibiotics.