Vitamin B is not a single vitamin but a complex of several water-soluble vitamins, each with its own unique properties. The term "vitamin B" encompasses a group of eight B vitamins, often referred to as the B-complex vitamins. Each of these vitamins was identified by different scientists over time:
1. **Thiamine (Vitamin B1)**: Thiamine was the first B vitamin to be discovered. It was isolated and identified by the Polish biochemist Casimir Funk in 1912.
2. **Riboflavin (Vitamin B2)**: Riboflavin was isolated and identified by the British chemist Richard Kuhn in the 1930s.
3. **Niacin (Vitamin B3)**: Niacin was first isolated by American biochemist Conrad Elvehjem in the 1930s.
4. **Pantothenic Acid (Vitamin B5)**: The identification of pantothenic acid is attributed to American biochemist Roger J. Williams in the 1930s.
5. **Pyridoxine (Vitamin B6)**: The discovery of pyridoxine is credited to American scientist Paul Gyorgy in the 1930s.
6. **Biotin (Vitamin B7)**: Biotin was identified by various researchers in the early 20th century, but its structure was elucidated by Vincent du Vigneaud in the 1940s.
7. **Folic Acid (Vitamin B9)**: Folic acid was discovered by American biochemist Lucy Wills in the 1930s, and its chemical structure was established later.
8. **Cobalamin (Vitamin B12)**: The discovery of vitamin B12 is attributed to several scientists, including George Whipple, George Minot, and William Murphy, who collectively identified its importance in the treatment of pernicious anemia in the 1920s.
The collective work of these scientists over the years led to the identification and understanding of the various B-complex vitamins, each of which plays a crucial role in maintaining human health.