Snail slime is commercially obtained from the common garden snail species Helix aspersa, which produces a secretion rich in proteins of high and low molecular weight hyaluronic acid and antioxidants. The secretion of the snail supposedly has a double function when applied to human skin: on one hand it is claimed to stimulate the formation of collagen, elastin and dermal components that repair the signs of photoaging and, second, is claimed to minimize the damage generated by free radicals that are responsible for premature skin aging.
Snail enzyme is a high-efficacy active ingredient comprised of proteins, glycolic acids and elastin commonly found in skin creams and sheet masks.This trusted slime is derived from the same stuff snails produce to heal cuts on their soft bodies from rocks and other rough surfaces. In beauty products, snail mucin firms and restores skin by replenishing moisture and supporting cell regeneration (which helps fade acne scars, smooth uneven complexions and reduce hyperpigmentation).
Since it is a complex mixture of glycolic acids, protein, hyaluronic acid, peptides, and other beneficial elements, the slime that is extracted from live snails can be an extremely powerful aid in moisturizing and healing skin. According to several studies “snail extract improves skin condition by increasing the dermis’ natural ability to take up and hold water… and suggest that the slime might have topical wound healing properties.”
Read this article from marie Claire magazine - http://www.marieclaire.com/beauty/a13977/popular-ingredients-youll-find-in-asian-korean-skincare/