French to English Science Chemistry; Chem Sci/Eng

In a text about a skin-whitening product which works through the action of vitamin C derivatives. Context: "Les UVs activent la mélanogénèse par l’intermédiaire de signaux, de type radicalaire et inflammatoire notamment. Pour une action globale de notre essence, deux actifs ont été spécifiquement choisis pour neutraliser ces messagers." Would "notre essence" refer to the product which the text is describing? Would the "signals" be "radical and inflammatory", and could you refer to them in English as "messengers", please? any help gratefully received!