The Study Of Tyrosinase Inhibitor From Moraceae Herbs

As the rate-limiting enzyme causing melanin formation, tyrosinase has a close relation with aging, wounds healing, development of insects and the browning in vegetables and fruits. Therefore, the study of tyrosinase inhibitor is of great practical value, especially in the fields of whitening cosmetics and preservation of vegetables and fruits. To date the study of tyrosinase inhibitor from Moraceae herbs is still less, not alone the comparing study to the common Moraceae herbs.In the study, the inhibition effects on tyrosinase and antioxidation, mechanisms and the strawberry preservation of Moraceae herbs were researched. The key results are shown as below:1. Evaluating the effects of Moraceae herbs on inhibiting tyrosinase and antioxidation. L-Tyrosine and L-Dopa were used as the substrates respectively to study the inhibitory abilities of Moraceae herbs against monophenoloxidase (MPO) and diphenoloxidase (DPO). Besides, their antioxidation abilities were also evaluated using superoxide radicals, DPPH radicals and ABTS radicals, respectively. The results showed that Cortex mori had a significant inhibition effects on tyrosinase and scavenging radical.2. Defining the mechanisms of extracts from Cortex mori in inhibiting tyrosinase. The mechanism was defined as a reversible mixed-type by Lineweaver-Burk plot. And the KI and KIS value was 4.34 mg/mL and 23.26 mg/mL, respectively.3. Studying the preservation abilities of Cortex mori. The preserved solution can effectively reduce the rate of rotting and the weightlessness, as well as the loss of Vitamin C and carbohydrates in strawberries. It also showed that Cortex mori had no evident influence on PPO and POD in strawberries.In summary, Cortex mori is a good tyrosinase inhibitor from moraceae, exhibiting a potentional application value in vegetables and fruits preservation and skin whitening.