Hydrolyzed Extensin

Hydrolyzed extensin is a plant-derived hydrolyzed glycoprotein used as a film-forming/conditioning ingredient, typically at low percentages (about 0.1–2%) in moisturizers and soothing serums. Hydrolyzed proteins of this type are generally well-tolerated and not inherently irritating, but they carry a small, documented risk of irritation or sensitization in highly reactive or eczema-prone individuals due to their botanical protein nature. Given the low typical use levels and overall good tolerability but non-zero allergy potential, it fits best as very gentle rather than inert. Safety Notes: Hydrolyzed extensin (a hydrolyzed plant glycoprotein/“extensin” film-former used for conditioning/skin-feel) is typically dosed at very low levels in mass-market leave-on lotions/serums and rinse-off cleansers where it appears near the end of the INCI list (commonly around 0.001–0.1%). Higher-strength consumer products marketed for firming/tightening, lifting, or biomimetic protein film-forming effects (leave-on masks/serums) have been observed using about 0.5–2% depending on supplier activity and solids, with >2% being uncommon due to viscosity, tack/film feel, and cost constraints; no specific FDA/EU concentration limit is established beyond general cosmetic safety requirements.