Investigation of the total phenolic content, antioxidant properties and effects of some fruit-vegetables and pulp on enzymatic browning

In this study, total phenolic compounds were extracted from arbutus fruits and leaves, quince peel, seeds and leaves, pomegranate, apple, black carrot pulp, olive pomace, damson peel and rosehip fruit. Their ABTS and DPPH activities, as antioxidant properties, as well as polyphenol oxidase (PPO) inhibitory activities were determined. Moreover, the effects of the extracts on enzymatic browning were investigated by measuring the color parameters by applying dipping and spraying methods on the apple slices. Among these extracts, Arbutus unedo leaf has the highest phenolic content with a value of 226.95±6.35 mg GAE/g extract. In addition, this extract showed the highest DPPH and ABTS activity with IC 50 values of 25.38±0.35 μg/ml and 2.33±0.22 μg/ml, respectively. Extracts from all materials inhibited the PPO enzyme. It was observed that the extract of Arbutus unedo leaf had the highest inhibitory effect with an IC 50 value of 16.90±3.21 µg/ml. It was determined that the extract solutions of the Arbutus unedo fruit and leaf showed the best effect against enzymatic browning by According to the obtained results, it was observed that most of these samples, whichare not widely used in the food industry or are encountered as waste, have antioxidant and PPO inhibitor properties. Due to their properties, it is considered that these materials can be recycled as a value-added product to the economy by applying different processes. Keywords: Antioxidant activity, enzymatic browning, extraction, total phenolic compound