What are the ingredients in B-Minus sourced from?

Ingredient	Source
Thiamin (as thiamine hydrochloride), Riboflavin (as riboflavin-5'-phosphate sodium), Niacin (as inositol hexanicotinate and niacin USP), Vitamin B6 (as pyridoxal-5'-phosphate sodium), Biotin,  Pantothenic Acid (as d-calcium pantothenate)	Synthetic