Mention the contribution of microbes in the production of antibiotics.

(N/A) Antibiotics produced by microbes are regarded as one of the most significant discoveries of the $20^{th}$ century and have greatly contributed to the welfare of human society.
- The term 'Antibiotic' is derived from two Greek words: 'anti' meaning 'against' and 'bio' meaning 'life'. Together, they mean 'against life' in the context of disease-causing organisms.
- However, with reference to human beings, they are 'pro-life' and not against life.
- Antibiotics are chemical substances produced by some microbes that can kill or retard the growth of other disease-causing microbes.
- Penicillin was the first antibiotic to be discovered.
- While working on $Staphylococci$ bacteria, Alexander Fleming observed a mould growing in one of his unwashed culture plates around which $Staphylococci$ could not grow. He discovered that this was due to a chemical produced by the mould, which he named 'penicillin' after the mould $Penicillium \text{ } notatum$.
- The full potential of penicillin as an effective antibiotic was established much later by Ernest Chain and Howard Florey.
- This antibiotic was extensively used to treat American soldiers wounded in World War-$II$.
- Fleming, Chain, and Florey were awarded the Nobel Prize in $1945$ for this discovery.
- After penicillin, many other antibiotics were purified from various microbes.
- Antibiotics have greatly improved our capacity to treat deadly diseases such as plague, whooping cough, diphtheria, and leprosy, which used to kill millions of people all over the globe.