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  • Author: Joanna Zielonka-Brzezicka x
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Open access

Anna Muzykiewicz, Joanna Zielonka-Brzezicka and Adam Klimowicz

Summary

Introduction: Quince (Cydonia oblonga Mill.) is a plant of which both the fruits and the leaves are sources of compounds with antioxidant potential. Such activity could be helpful to prevent the development of so-called oxidative stress.

Objective: The aim of the study was to evaluate the antioxidant properties of ethanolic, methanolic and acetonic extracts of mature and immature quince fruits, as well as leaves.

Methods: The extracts were prepared using ultrasound-assisted extraction, for 15, 30 and 60 minutes. The antioxidant activity was assessed by DPPH, FRAP, ABTS and Folin-Ciocalteu (F-C) methods.

Results: Antioxidant activity of all of the evaluated extracts were observed. The highest potential determined with each method was found for leaf extracts. Moreover, higher activity of unripe fruit extracts compared to ripe fruit was observed. Taking into account the applied extractants, the highest antioxidant capacity was found for methanolic extracts, extracted for 60 and 30 minutes. By contrast, the lowest potential was observed mainly for ethanolic extracts (extraction time 15 minutes).

Conclusion: Quince extracts, particularly alcoholic extracts of leaves, seem to be a valuable source of anti-oxidants. Factors as extraction time, the type of solvent and degree of fruit maturity may influence the antioxidant activity of extracts.

Open access

Anna Muzykiewicz, Joanna Zielonka-Brzezicka and Adam Klimowicz

Summary

Introduction: Antioxidants, isolated from different plant parts, are widely used due to their ability to prevent the development of so-called oxidative stress. Sea buckthorn (Hippophae rhamnoides L.) is one of the plants with expected antioxidant properties.

Objective: The aim of the study was to evaluate the antioxidant activity of ethanolic, methanolic and acetonic extracts of H. rhamnoides leaves, ripe and unripe fruits obtained by ultrasound-assisted extraction.

Methods: To estimate the antioxidant potential of the extracts the DPPH, FRAP, ABTS and Folin-Ciocalteu methods were applied. Moreover, the influence of the extrahent, as well as extraction time, on this activity was evaluated.

Results: Sea buckthorn leaf extracts showed higher activity, contrary to the fruit extracts. Moreover, higher activity of ripe fruit extracts compared to unripe material extracts was found. To obtain the highest content of antioxidants in the extracts, ultrasound-assisted extraction for 60 min with methanol should be applied.

Conclusions: The presented in vitro results could lead to the conclusion that H. rhamnoides seems to be a valuable source of antioxidants to be applied in various branches of industry.