for one-half maximal growth these organisms required the addition of one of the active forms of the b6 vitamin , pyridoxal with hcl ( 0.16-1.45 mug/ml ) or pyridoxamine dihydrochloride ( 0.67-2.0 mug/ml ) , or addition of l-cysteine ( 0.235-0.425 mg/ml ) to routine bacteriological media .
C0087162
b6 vitamin
C0034263
pyridoxal