Light micrograph (LM) of Vitamin B6 (pyridoxine) and Vitamin B2 (riboflavin) crystals. Vitamin B6 is a water-soluble vitamin that is needed for more than 100 enzymes involved in protein metabolism. It is also essential for red blood cell metabolism. The nervous and immune systems need vitamin B6 to function efficiently, and it is also needed for the conversion of tryptophan to niacin (Vitamin B3). Vitamin B6 deficiency can result in pyroluria. Vitamin B2 (riboflavin) is a soluble and heat stable factor in B complex vitamins. Like the other B vitamins, it supports energy production by aiding in the metabolism of fats, carbohydrates, and proteins. Vitamin B2 is also required for red blood cell formation and respiration, antibody production, and for regulating human growth and reproduction. Riboflavin also helps in the prevention or treatment of many types of eye disorders, including some cases of cataracts. Magnification: x25 when shortest axis printed