3.5. Skin irritation evaluation
The quantitative evaluation of irritation was done by determining the changing levels of index “a*”
and TEWL after 4 weeks of daily topical application of samples.
As shown in Fig. 5, the change of “a*” and TEWL after hesperetin microemulsion applied was lower than that of control (non-treatment),
indicating that hesperetin microemulsion had an inhibition irritation effect.
This might be attributed to the anti-inflammatory effect of flavonoids.