The correct answer is option (2) Chloramphenicol.
Chloramphenicol is a broad-spectrum antibiotic that was originally isolated from the soil bacterium Streptomyces venezuelae. It is effective against a wide range of bacteria and has been used to treat various bacterial infections, including typhoid fever.
Here is a detailed explanation of Chloramphenicol:
1. Chemical Structure:
Chloramphenicol has a complex chemical structure. It contains a chlorine atom, which is important for its antibacterial activity.
2. Mechanism of Action:
Chloramphenicol works by inhibiting bacterial protein synthesis. It specifically targets the 50S subunit of the bacterial ribosome, preventing the formation of peptide bonds during protein synthesis.
This interference with protein synthesis disrupts the growth and multiplication of bacteria, leading to their eventual death.
3. Activity Against Typhoid Fever:
Chloramphenicol has historically been used in the treatment of typhoid fever, a systemic infection caused by the bacterium Salmonella typhi.
Typhoid fever is a serious illness characterized by prolonged fever, headache, nausea, and abdominal pain. If left untreated, it can be fatal.
4. Administration:
Chloramphenicol can be administered orally or intravenously, depending on the severity of the infection.
In the case of typhoid fever, where systemic treatment is often required, intravenous administration may be preferred.
5. Drawbacks and Limitations:
While Chloramphenicol is effective, its use has declined over the years due to the availability of other antibiotics and concerns about potential side effects.
One significant concern is the risk of a rare but serious adverse reaction called aplastic anemia, which can affect the bone marrow and lead to a decrease in red and white blood cell counts.
6. Regulation and Monitoring:
Due to the potential for serious side effects, the use of Chloramphenicol is now more restricted, and its administration is closely monitored.
In many countries, it is considered a second-line or reserve antibiotic, used when other, less toxic antibiotics are not suitable or available.
7. Alternatives:
Other antibiotics, such as fluoroquinolones and third-generation cephalosporins, are often preferred for the treatment of typhoid fever in modern medical practice. These alternatives are considered safer and have fewer side effects.
In summary, Chloramphenicol is an antibiotic that has been historically used, including in the treatment of typhoid fever. However, its use has decreased over time due to concerns about potential side effects, and it is now reserved for specific situations where alternative antibiotics may not be suitable. | 
