Tyrosinase Inhibitory and Antioxidant Activity of Wild Prunus spinosa L. Fruit Extracts as Natural Source of Bioactive Compounds

In recent years, naturally derived tyrosinase inhibitors and antioxidants have become very important, since the synthetic ones are related with several side effects. As wild fruits are rich source of bioactive compounds, this study focused on the examination of Prunus spinosa L. (blackthorn) fruit extracts, widely distributed in our country. However, blackthorn extracts are not enough investigated, and there are only a few published works. Extraction efficiency of P. spinosa ultrasonic fruit extracts obtained by using different solvents (methanol, 70% (v/v) ethanol, 45% (w/w) propylene glycol and water) was evaluated, regarding polyphenolic profile, tyrosinase inhibitory and antioxidant activity. Results suggested that extracts with 45% propylene glycol and water were particularly rich in polyphenolic compounds (especially phenols, flavonoids and anthocyanins). The highest extraction yield was for 45% propylene glycol extract. This extract showed higher tyrosinase inhibitory and antioxidant activity compared to others, while the methanolic extracts had the highest chelating capacity. Therefore, P. spinosa fruit extracts, especially extracts obtained by ultrasonic extraction with 45% propylene glycol, have a great potential to be incorporated in some pharmaceutical formulations for obtaining tyrosinase inhibitory and antioxidant effects.