What are the active ingredients in Active B12 with L-5-MTHF lozenge derived from? Ceylon Keeslar October 31, 2019 17:22 Updated Follow Vitamin B12 as adenosylcobalamin is from fermentation. Vitamin B12 as methylcobalamin and folate are synthetic. Related articles Does Active B12 with L-5MTHF lozenge contain gluten, soy, or grains? What is the reasoning for each ingredient in Active B12 with L-5MTHF lozenge? How do I take Active B12 with L-5MTHF lozenge? What are the ingredients in Optimal Prenatal derived from? Who is Optimal GI capsules intended for? Comments 0 comments Article is closed for comments.