Current Trends in Natural Sciences Vol. 11, Issue 22, pp. 06-18, 2022 https://doi.org/10.47068/ctns.2022.v11i22.001 Current Trends in Natural Sciences (on-line) Current Trends in Natural Sciences (CD-Rom) ISSN: 2284-953X ISSN: 2284-9521 ISSN-L: 2284-9521 ISSN-L: 2284-9521 http://www.natsci.upit.ro *Corresponding author, E-mail address: sinacosmulescu@hotmail.com 6 EXTRACTION TIME INFLUENCE ON THE PHENOLIC AND CAROTENOID LEVEL, AND THE DYNAMICS OF ANTIOXIDANT ACTION OF CHOKEBERRY DRY RESIDUE Ivona Cristina Enescu (Mazilu) 1, 2 , Sina Cosmulescu 3, * , Daniela Giosanu 4 , Loredana Elena Vijan 4 1 Research Institute for Fruit Growing Marului 402, 117450, Maracineni, Arges Romania 2 University of Craiova, Doctoral School of Plant and Animal Resources Engineering Horticulture Faculty, Alexandru Ioan Cuza 13, 200585, Craiova, Romania 3 University of Craiova, Horticulture Faculty, Department of Horticulture and Food Science, Craiova, Alexandru Ioan Cuza 13, 200585, Craiova, Romania 4 University of Pitesti, Targu din Vale 1, 110040, Pitesti, Romania Abstract This study aimed to analyze the extraction time influences on some phenolics and carotenoids determined in the chokeberry dehydrated residue. In addition, the dynamics of the DPPH· radical reduction under the influence of the different amounts of chokeberry extract and reaction time were registered. For this purpose, fruits belonging to the ’Melrom’ and ’Nero’ cultivars grown in the experimental plots of the Research Institute for Fruit Growing Maracineni - Arges were harvested at full maturity, in the middle of August 2021 and pressed for juice extraction. The resulting pomace was subjected to convective dehydration at 45ºC. Values of 12286.11-16560.88 mg GAE/100g DW for TPC, 6567.96-9428.90 mg GAE/100 g DW for TTC, and 3293.74-5109.63 mg CE/100 g DW for TFC were registered. Lycopene and -carotene ranged between 0.78-1.43 mg/100 g DW and 0.21-0.37 mg/100 g DW. Longer ultrasound treatment led to higher TPC and TFC, while TTC decreased after 60 minutes. Raising the extraction time by at least 24 hours resulted in higher amounts of carotenoids. The lowest remanent radical activity (A=20.55%) was determined for the 50 and 60 μL extract doses. In this case, A% was minimal after 20 minutes of the DPPH reduction reaction (12.62- 12.94 %), but not significantly different compared to the values determined after the first 8 minutes of the reaction (17.59-19.11 %). Keywords: Aronia melanocarpa, flavonoids, lycopene, polyphenols, tannins, -carotene 1. INTRODUCTION Plant chemical constituents focused attention in the very early days of modern science since plants were used for many purposes besides food, such as medical treatment and cloth dying. Anthocyanins were first investigated in 1664, while plant alkaloids were first isolated in crystalline form between1817-1820. Still, the large world of plant chemicals was brought to be known after de Second World War, through the development of new elaborated analysis techniques (Harborne, 1999). Recently many studies regarding plants' biochemical components and their biological activities were conducted and their results showed that an increased intake of food rich in natural antioxidants is associated with lower risks of degenerative diseases, particularly cardiovascular diseases and cancer (Pérez-Jiménez et al., 2008).