Abstract
The pomegranate phenolics are reported to have cutaneous benefits and to be effective
in treating skin disorders, including hyperpigmentation. In this context, a preparation
method was developed by which to obtain phenolic-rich pomegranate peel extract. Sinapic
acid was presented as the major pomegranate peel phenolics, followed by gallic and
ellagic acids, and 4 additional phenolics. The extract exhibited strong antioxidant
activity with an in vitro tyrosinase inhibitory effect. The skin hyperpigmentation treating potency was confirmed
by the suppression of cellular melanogenesis through tyrosinase and TRP-2 inhibitions
as examined in the B16F10 melanoma cells. Cellular antioxidant and proliferative activities
of the extract toward human dermal fibroblasts were evidenced, as well as an inhibitory
effect against MMP-2. The extract was developed into the stable serum and mask. The
products were proved to be non-irritated in 30 Thai volunteers participating in a
single application closed patch test. A split-face, randomized, double-blind, placebo-controlled
test of the skin lightening effect was evaluated in the 30 volunteers over 28 consecutive
daily treatments and monitored by the Mexameter MX 18. The active serum and mask were
better in facial skin lightening efficacy than the placebo (p < 0.005). That was in
accordance with the sensory evaluation scored by the volunteers. Phenolic-rich pomegranate
peel extract is evidenced as a safe herbal derived material promising for skin hyperpigmentation
treatment. Supportive information regarding chemical and biological profiles is presented
with the confirmed safety and cutaneous benefits in volunteers.
Key words
Punica granatum
- Lythraceae - pomegranate - phenolics -
in vitro activities - cellular activities - skin lightening - clinical trials
