Differences between primary and secondary metabolite:

PRIMARY METABOLITE:

1. Required for the growth and maintenance of cellular functions.
2. Starting substrates of a medium.
3. Consist of vitamins, amino acids, nucleotides etc.
4. Necessary at log phase of microbial growth.
5. Produced to perform physiological functions and support in development of cell.
6. Same in every species means they produce same product.
7. Produced in large quantities.

SECONDARY METABOLITE:

1. Not required for growth.
2. End products of primary metabolite.
3. Consist of antibiotics, steroids, toxins etc.
4. Produced during stationary phase of cell growth.
5. Important in ecological and other activities of the cell.
6. Varies in different species.
7. Produced in small quantities.