Among the listed antibiotics, which cephalosporin shows greater activity than penicillin against various Salmonella species?

Introduction / Context:Cephalosporins are beta-lactam antibiotics with a broader Gram-negative spectrum than many penicillins. This question asks which cephalosporin, among the options, is known to be more active than penicillin against Salmonella species.

Given Data / Assumptions:

• Focus organisms: Salmonella spp. (Gram-negative).
• Comparison baseline: penicillin activity.
• Compounds listed include cephalosporin C and N, and Synnematin (not a standard cephalosporin reference for Salmonella therapy).

Concept / Approach:Cephalosporin C is a natural cephalosporin with better inherent activity against many Gram-negative rods than classic penicillins. While cephalosporin N is penicillin-like and historically considered closer to a penicillin derivative, cephalosporin C exhibits the broader Gram-negative profile aligning with Salmonella susceptibility compared to early penicillins.

Step-by-Step Solution:Recognize Salmonella as Gram-negative enteric bacteria.Recall that cephalosporin C shows improved Gram-negative activity over early penicillins.Note that cephalosporin N is less distinct from penicillins in activity spectrum.Select cephalosporin C as the better option against Salmonella.

Verification / Alternative check:Historical antimicrobial spectra summaries place cephalosporin C ahead of baseline penicillin against many enteric Gram-negatives in vitro, consistent with the question’s framing.

Why Other Options Are Wrong:Cephalosporin N: more penicillin-like; not superior to penicillin across Salmonella.Synnematin: not a standard cephalosporin used for Salmonella and not superior to penicillin in this context.Both (a) and (c): includes incorrect elements.

Common Pitfalls:Assuming all cephalosporins outperform penicillins on every Gram-negative organism; activity varies by agent and species.

Final Answer:Cephalosporin C