Symphytum Officinale Callus Culture Extract Good Antioxidant Anti-Ageing Symphytum Officinale Callus Culture Extract at a glance Stem cell extract from the comfrey plant Has antioxidant and soothing properties Helps improve some visible signs of aging Does not present the same problems for skin as pure comfrey Symphytum Officinale Callus Culture Extract description _Symphytum officinale_ callus culture extract is the cell extract from the roots of a plant commonly known as comfrey. Specifically, it’s the cell extract from a root callus, soft tissue that forms over a wounded plant surface and can produce growth itself; essentially, a stem cell extract. Much has been made in recent years of plant stem cells’ abilities to rejuvenate skin. Though a lot of it is overstated, research finds that _Symphytom officinale_ callus culture extract does exhibit antioxidant and calming abilities that help fight visible signs of aging. The phenolic compounds within this extract make it a worthwhile ingredient to consider in anti-aging formulas. One note: while comfrey extract itself has alkaloid content that can irritate skin, the same is not true of its callus culture extract. As of the time of this writing, the independent Cosmetic Ingredient Review panel has not reported on the safety of _Symphytum officinale_ callus culture extract as used in cosmetics. According to the supplier, use levels of _Symphytum officinale_ callus culture extract ranges from 0.4–1% in a water base that also contains isomalt, lecithin, and sodium benzoate. Related ingredients: Comfrey Extract