All of this is achievable through highly researched acid-based ingredients, also called actives in skincare. Here are some actives to look out for in trending skincare products. Emerging Acid-based Skincare Ingredients: Source, Application, and Product Acid Derived from Application Product Polyglutamic acid (PGA) Produced by microbial fermentation, including fermentation associated with soybeans Hydration, moisture retention, smoother-looking skin and reducing surface water loss The INKEY List Polyglutamic Acid Serum; Minimalist Hyaluronic + PGA 2% Face Serum. Caffeic acid Naturally found in coffee, grapes, berries, olives and various vegetables Antioxidant protection and research into photoageing and inflammation Ariul Green Vitamin C Toning Ampoule lists caffeic acid in its ingredient list. Gallic acid Found in gallnuts, tea, grapes, berries and other plant materials Antioxidant protection and formulations targeting visible signs of environmental stress and uneven skin tone Cetaphil Advanced Daily Defense Serum and Cetaphil Repair & Renew Serum feature a gallic-acid and vitamin E antioxidant complex. Succinic acid Occurs naturally in plant and animal tissues; can also be produced through fermentation or chemical synthesis Blemish-focused products, oily-skin care and formulations targeting visible breakouts The INKEY List Succinic Acid Acne Treatment combines succinic acid with sulfur and salicylic acid. Lactobionic acid Produced from lactose through oxidation Gentle exfoliation, hydration, antioxidant care and formulations for dry or sensitive skin Oriflame Novage+ Proceuticals Micro Essence Multi Mist; Be Neude C-Bionic 20% Vitamin C Face Serum. Shikimic acid Naturally occurs in star anise and other plants; also produced through industrial biosynthesis Exfoliation, skin-texture refinement and formulations targeting uneven tone NEORETIN Discrom Control Lightening Peel lists shikimic acid alongside glycolic and citric acids. Rosmarinic acid Found in rosemary, sage, lemon balm and other herbs Antioxidant and soothing formulations, particularly those targeting visible redness and skin discomfort Allies of Skin Molecular Multi Nutrient & Dioic Cream is listed among products containing rosmarinic acid. Research has also backed the presence of certain actives in PGA and rosmarinic acid. Recent research on the viability of these acid-based ingredients is listed below: Poly-γ-glutamic Acid: Effects on Skin Barrier Function and Hyaluronic Acid Synthesis Acid Polyglutamic Acid (PGA) Research Focus Investigating the effects of microbially produced PGA on skin-barrier function, moisture retention and hyaluronic acid synthesis Key Findings Preclinical testing showed increased skin-barrier marker expression and hyaluronic acid synthesis in cultured skin cells and reconstructed skin models Published International Journal of Molecular Sciences (2025) Research on Rosmarinic Acid and TRPV3 Ion Channel Inhibition in Skin Acid Rosmarinic Acid Research Focus Investigating the effects of rosmarinic acid and related compounds on the TRPV3 ion channel and inflammatory signalling associated with skin sensitivity Key Findings Laboratory experiments indicated inhibition of TRPV3 activity, suggesting potential for skin-soothing formulations. Further human studies are needed to confirm these effects. Published Journal of Biological Chemistry Share this article