Apple and pear are important fruit trees in Slovenia. During the annual cut and orchards renovation waste (branches and wood) is formed, which is mulched or used as firewood. This waste could be useful source for the production of phenolic antioxidants, as the cosmetics industry follows the trend of using natural ingredients. Therefore, we wanted to check the content of total phenols and the anti-oxidative activity in branches of apple in pear trees. We were also interested in which fruit species and their variety have a higher content of phenolic compounds and anti-oxidative activity, or are there differences between various branch thickness in the total phenol content and anti-oxidative activity, and whether the content of phenolic compounds and the anti-oxidative activity is different during the growing season or winter dormancy. Since the process is long, we wanted to check whether the total phenols content and anti-oxidative activity are changing with the extension of time from branch cutting to analysis. According to the Folin - Ciocalteu method, we determined the content of total phenols, and with DPPH and ABTS methods we determined the anti-oxidative activity. We found that in the content of phenolic compounds there were no statistically significant differences between fruit species, but anti-oxidative activity was higher for extracts made from pear branches. Varieties, both for apple and pear, did not affect the content of phenolic compounds; there was no difference in anti-oxidative activity in pear varieties, while apple variety 'Granny Smith' had the highest anti-oxidative activity. The thickness of the branches does not affect the content of phenolic compounds and anti-oxidative activity, which is advantageous for the use of waste branches and wood for industrial purposes. In the hollow ball stage (right before blooming), both fruit species have a higher anti-oxidative activity, while there were no differences in the content of total phenols. It is recommended that additional analyses of individual phenols and anti-oxidative activity are carried out, which will more precisely explain the anti-oxidative potential and the content of phenolic compounds in the branch extract of apple and pear trees.
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