Although aged black garlic has various biological activities such as anti-allergy, anti-inflammation and neuroprotection, effect of aged black garlic on chemically contact dermatitis is unclarified.

To evaluate anti-dermatitic activity of aged black garlic extract, we investigated effects of a fraction of aged black garlic extract (BG10) on both in vivo and in vitro .

BG10 almost inhibited formation of nitric monoxide and interleukin-6 (IL-6; IC₅₀, 7.07 µg/mL) at 25 µg/mL, and dose-dependently reduced production of tumor necrosis factor-α (TNF-α; IC₅₀, 52.07 µg/mL) and prostaglandin E₂ (IC₅₀, 38.46 µg/mL) in lipopolysaccharide-stimulated RAW264.7 cells. In addition, BG10 significantly inhibited the expression of inducible nitric oxide synthase, cyclooxygenase-2 and nuclear NF-κB, and improved that of cytosolic levels of NF-κB and IκBα in the cells. Consistent with in vitro studies, BG10 (0.5 mg/mL) not only reduced ear edema but also suppressed the formation of IL-6 and TNF-α induced by 12- O -tetradecanoylphorbol-13-acetate in ear tissues of mice.

These findings suggest BG10 has anti-dermatitic activity through inhibiting activation of macrophages. Therefore, such effects of BG10 may provide information for the application of aged black garlic for prevention and therapy of contact dermatitis.