This is a single-center, double-blinded, placebo-controlled, prospective clinical study designed to evaluate the skin barrier repair efficacy and local tolerance of topical cosmetic formulations containing a botanical extract. Skin barrier challenge is induced via standardized tape stripping on the volar forearm of healthy subjects. The study will evaluate and compare the repair kinetics of two concentrations of the active formulation, a vehicle, and an untreated control zone over a 14-day application period.

Healthy female subjects will undergo a standardized skin barrier challenge (tape-stripping) on designated zones of their volar forearms at baseline. Formulations containing different concentrations of a botanical extract (Active Formulation A and Active Formulation B), a vehicle control, and an untreated control will be assigned to the randomized zones. Products will be applied topically twice daily for 14 days. Skin barrier repair efficacy will be assessed using clinical gradings and instrumental measurements, including Trans-Epidermal Water Loss (TEWL) and skin hydration. Local tolerance will be evaluated via clinical grading. Non-invasive skin surface biomaterial collection may be performed at designated time points for skin proteomics and lipidomics analysis.

Inclusion Criteria:

1. Chinese women aged 35 to 60 years in good general health.
2. Self-reported dry skin type.
3. a hydration index < 35 and a trans-epidermal water loss (TEWL) ≥ 6g.m-2.h-1 on both anterior sides of the forearms at screening.
4. Willingness to avoid excessive sun exposure and comply with all study procedures including tape stripping and biosampling.
5. Bilateral forearms clear of scars, wounds, or significant pigment spots.

Exclusion Criteria:

1. Current pregnancy, breastfeeding, or planning to become pregnant.
2. Current smokers or history of smoking within the last 6 months (including e-cigarettes/nicotine products).
3. History of facial cosmetic procedures (fillers, lasers, implants, Botox, etc.).
4. Active systemic or localized skin diseases (acne, eczema, psoriasis, atopic dermatitis).
5. Allergies to cosmetics, personal care products, or their ingredients.
6. Excessive UV exposure or frequent sauna/water sports usage.
7. Use of antihistamines, antibiotics, corticosteroids, or NSAIDs within the relevant washout periods.
8. Participation in any other clinical trial within the past 30 days.