Comparative analysis of different groups of phenolic compounds in fruit and leaf extracts of Aronia sp.: A. melanocarpa, A. arbutifolia, and A. ×prunifolia and their antioxidant activities

Eur Food Res Technol DOI 10.1007/s00217-017-2872-8 ORIGINAL PAPER Comparative analysis of different groups of phenolic compounds in fruit and leaf extracts of Aronia sp.: A. melanocarpa, A. arbutifolia, and A. ×prunifolia and their antioxidant activities Agnieszka Szopa1 · Adam Kokotkiewicz2 · Paweł Kubica1 · Piotr Banaszczak3 · Agnieszka Wojtanowska‑Krośniak4 · Mirosław Krośniak4 · Urszula Marzec‑Wróblewska5 · Anna Badura5 · Paweł Zagrodzki4,6 · Adam Bucinski5 · Maria Luczkiewicz2 · Halina Ekiert1 Received: 26 September 2016 / Revised: 28 February 2017 / Accepted: 10 March 2017 © The Author(s) 2017. This article is an open access publication Abstract Anthocyanins, flavonols, and phenolic acids were estimated in methanolic extracts from the fruits and leaves of three chokeberries—Aronia melanocarpa, Aronia arbutifolia, and Aronia ×prunifolia. The fruits contained significant amounts of cyanidin glycosides (0.3– 323.2 mg/100 g DW) and two phenolic acids: chlorogenic acid (16.3–273.5 mg/100 g DW) and neochlorogenic acid (92.3–212.6 mg/100 g DW). The leaf extracts contained high amounts of flavonols: quercetin, quercitrin, and rutin (62.1–367.0 mg/100 g DW), as well as chlorogenic acid, Electronic supplementary material The online version of this article (doi:10.1007/s00217-017-2872-8) contains supplementary material, which is available to authorized users. * Agnieszka Szopa 1 Chair and Department of Pharmaceutical Botany, Jagiellonian University, Medical College, ul. Medyczna 9, 30‑688 Kraków, Poland 2 Chair and Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Gdansk, al. gen. J. Hallera 107, 80‑416 Gdańsk, Poland 3 Rogów Arboretum, Forest Experimental Station, Warsaw University of Life Sciences, ul. Leśna 5b, 95‑063 Rogów, Poland 4 Department of Food Chemistry and Nutrition, Jagiellonian University, Medical College, ul. Medyczna 9, 30‑688 Kraków, Poland 5 Department of Biopharmacy, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, ul. dr A. Jurasza 2, 85‑089 Bydgoszcz, Poland 6 Department of Nuclear Physical Chemistry, Institute of Nuclear Physics, ul. Radzikowskiego 152, 31‑342 Kraków, Poland neochlorogenic acid, and rosmarinic acid (max. 724.2, 482.7, 154.7 mg/100 g DW, respectively). Of the examined materials, A. arbutifolia leaves were characterized by the highest total phenolics content (9148.2 mg gal. ac. Eq./100 g DW) and showed the highest antioxidant activity in DPPH and FRAP assays. The results demonstrate that fruits of A. arbutifolia and A. ×prunifolia are a rich source of antioxidants and can be used as plant raw materials, alternatively to A. melanocarpa berries. Leaves of the investigated species are of potential therapeutic and dietary interest because of their high flavonol and phenolic acid content. Keywords Anthocyanins · Flavonols · Phenolic acids · Antioxidant activity · Total phenols · Black chokeberry · Red chokeberry · Purple chokeberry Introduction The fruit of Aronia melanocarpa (Michx.) Elliott (black chokeberry) is a well-known plant raw material used as a foodstuff, food supplement, and an ingredient in medicinal products and cosmetics. Numerous scientific studies have demonstrated antioxidant [1–3], anti-inflammatory [4], hepatoprotective, gastroprotective, UV protective [5], hypoglycemic, antimutagenic, and anticancer [6–9] properties of extracts from the fruits of black chokeberry. Scientific studies have also confirmed their beneficial effect on the cardiovascular system [2, 10, 11] and eye functioning [12]. The above-mentioned biological activities are attributed to phenolic compounds, mainly anthocyanins, flavonols, tannins, phenolic acids, organic acids, vitamins, and bioelements [13–16]. The fruit of A. melanocarpa proved to be extremely useful not only in phytotherapy, but also in 13 Vol.:(0123456789) Eur Food Res Technol the food industry, especially as an ingredient of functional foods. Two other chokeberries, Aronia arbutifolia (L.) Pers. (red chokeberry) and Aronia ×prunifolia (Marsh.) Rhed. (purple chokeberry), are less studied and hence little utilized by the pharmaceutical and agricultural crop industries [13]. All of three chokeberries analyzed in this study grow as shrubs in their natural habitats in North America. They are also successfully cultivated in Europe and Asia [13, 15, 17]. These chokeberries are similar in terms of growth habit, but some morphological features allow them to be distinguished. Ripe berries of A. melanocarpa are black, with a thick waxy coating. By comparison, the berries of A. ×prunifolia are purple black, while those of A. arbutifolia are smaller and bright red. Moreover, which is characteristic, the berries of A. arbutifolia remain durable in the winter time as they do not shrivel [13]. The chokeberry of particular interest is A. ×prunifolia which is a polyploid hybrid of A. melanocarpa and A. arbutifolia. It shows the intermediate morphological features between parent species, but is much closer to A. melanocarpa with almost the same blackish fruits and is often hardly determinable within the natural populations of that species. Furthermore, the individuals of A. ×prunifolia often show tendency to apomixis, which is also the reason for the high stability of this hybrid [18–20]. Aronia melanocarpa was originally exploited as a source of colorants for food and pharmaceutical industry and subsequently became the most popular and widely cultivated Aronia species [21]. A. arbutifolia and A. ×prunifolia, on the other hand, remained largely underutilized, and consequently, the reports on their chemical composition are scarce. Only a few studies demonstrated the presence of anthocyanins, phenolic acids, and flavonols in fruits of both plants [15, 19]. However, their polyphenol profile is not yet fully known and requires further studies [13]. The aim of this study was to comprehensively analyze, for the first time, the three chokeberry species: A. melanocarpa, A. arbutifolia, and A. ×prunifolia with respect to the most important groups of secondary metabolites they contain: anthocyanins, flavonols, and phenolic acids which are responsible for biological properties of aronia plants. The study involved mature fruits of arboretum-grown plants (black, purple, and red chokeberries, as well as fruits of A. melanocarpa used by some Polish herbal companies for the production of food supplements). Since leaves of several berry plants were demonstrated to contain substantial amounts of antioxidants for potential use in food and pharmaceutical industries [22], it was also decided to examine the leaves of the three Aronia species for the presence of aforementioned constituents. As harvest date was previously shown to affect secondary metabolite content of chokeberry leaves [23], these were collected at two 13 fruit maturation stages. A comprehensive insight into the qualitative and quantitative profiles of t (...truncated)