Explore 2 honest Biba de Sousa The Plant Stem Cell Serum With Peptides. Award-winning super rejuvenating serum that started the peptide serum craze. Two peptides, skin loving vitamins, herbal antioxidants and humectants will help you retexture, illuminate and rejuvenate your skin. Acne safe: Brown 1 fl oz video reviews from the Flip community to help you find out if it’s the right product for you.