negative regulation of androgen biosynthetic process
negative regulation of androst-4-ene-3,17-dione biosynthetic process
negative regulation of bile acid biosynthetic process
negative regulation of cobalamin metabolic process
negative regulation of estrogen biosynthetic process
negative regulation of helvolic acid biosynthetic process
negative regulation of L-ascorbic acid biosynthetic process
negative regulation of progesterone biosynthetic process +
negative regulation of retinoic acid biosynthetic process
negative regulation of steroid hormone biosynthetic process +
negative regulation of sterol biosynthetic process +
negative regulation of testosterone biosynthetic process
negative regulation of thiamine biosynthetic process
negative regulation of thiamine diphosphate biosynthetic process
negative regulation of vitamin D biosynthetic process
Any process that decreases the rate, frequency or extent of a vitamin D biosynthetic process. Vitamin D biosynthesis is the chemical reactions and pathways resulting in the formation of vitamin D, any of a group of related, fat-soluble compounds that are derived from delta-5,7 steroids and play a central role in calcium metabolism. Specific forms of vitamin D include calciferol (ergocalciferol; vitamin D2) and cholecalciferol (calciol; vitamin D3).
positive regulation of vitamin D biosynthetic process