Journal of Applied Botany and Food Quality 87, 175 - 181 (2014), DOI:10.5073/JABFQ.2014.087.025 1 Department of Pharmacy, Faculty of Medicine, University of Niš, Serbia 2 Institute for Biology and Human genetics, Faculty of Medicine, University of Niš, Serbia 3 Department of Ecology and Biology, Faculty of Sciences, University of Niš, Serbia Assessment of polyphenol content, in vitro antioxidant, antimicrobial and toxic potentials of wild growing and cultured rue Dragana R. Pavlović 1* , Marija Vukelić 2 , Stevo Najman 2 , Milica Kostić 1 , Bojan Zlatković 3 , Tanja Mihajilov-Krstev 3 , Dušanka Kitić 1 (Received March 12, 2014) * Corresponding author Summary Ruta graveolens L. (rue) is an edible medicinal plant that is tradition- ally used in various countries. This study aimed to investigate and compare the phenolic content, antioxidant capacity, antibacterial and cytotoxic activities of the methanolic and ethanolic extracts of wild growing and cultured rue. The total phenolic content of the tested ex- tracts varied from 57.90 to 166.91 mg of catechin equivalent (CE)/g of extract and the total favonoid content from 4.18 to 26.87 mg of rutin equivalent (Ru)/g of extract. All the tested samples exhibited signifcant antioxidant potential in DPPH radicals scavenging and lipid peroxidation inhibition assays (comparable with activity of rutin in the same test systems), antimicrobial activity determined by microdilution method (particularly against Gram (+) bacteria strains) and ability to induce inhibition of HeLa cells growth and prolife- ration (up to 71.81 %). In addition, rue-treated HeLa cells showed various morphological changes after 72 h of incubation with rue ex- tracts. Extracts from wild growing rue with the highest polyphenol, tannin and favonoid contents demonstrated the strongest activities in all tested systems. The present study also emphasized the fact that the rue leaves and herb should be harvested at the beginning of blos- soming stage in order to achieve the maximal level of secondary metabolites and optimal pharmacological effects. Introduction Ruta graveolens L. (Rutaceae), rue, is a shrub-like herbaceous perennial aromatic plant that is native to Mediterranean region (TOWNSEND, 1968). It is cultivated in the gardens all over the world, though preferably grows in Mediterranean climates. Rue is highly used in the traditional medicine in various countries to treat a variety of ailments, ranging from absence of menstruation to rheumatism and various mental conditions (PDR, 2000; TUCAKOV, 1997). Due to the lack of suffcient evidence of the effcacy of the drug in the proposed indications and the unfavorable ratio of beneft to risk, the Commission E gave the drug, rue leaves and herb, a nega- tive rating. Rue can cause contact dermatitis, phototoxic reactions, severe liver and kidney damage, while serious undesirable effects can occur even after administration of therapeutic doses (BLUMENTHAL, 1998; FRITZ WEISS and FINTELMANN, 2000). This edible plant has been part of East Asian diets for many years and has dual function as food and medicine (YANG et al., 2006). In the European Union, R. graveolens herb may be used as spice and favoring agent in certain food products as for instance baked goods, frozen dairy products, soft candy or non-alcoholic beverages. R. graveolens and its essential oil have been approved for Generally Recognized as Safe status by the United States Food and Drug Administration and may be added to human food as favoring agents (up to 2000 and 10 000 μg/kg, respectively). Rue herb and oil are also allowed in the United States in animal feedstuffs at the same levels (EMA, 1999). The plant contains active compounds like favonoids, alkaloids, cou- marin derivatives, lignans and essential oils (PDR, 2000). The drug (rue herb and/or leaves) is antimicrobial, abortifacient, and photo- sensitizing. As the current information shows, it expresses pharma- cological functions including anti-infammatory, analgesic, antian- drogenic, antihyperlipidemic, antihyperglycemic, xantine oxidase inhibition and anticancer activities, among others (ASGARPANAH and KHOSHKAM, 2012; YANG et al., 2006). VITKOVA and PHILIPOV (1999) conducted a comparative phyto- chemical study of rue with material from natural Bulgarian popula- tions of the species and from cultivated specimens. Their conclusion was that cultivation of rue revealed changes in the second metabolite composition. However, as far as our literature survey could ascertain, our study is the frst comparative study of effects of wild growing and cul- tured Ruta graveolens. The focus of our research was to explore and compare antimicrobial and antioxidant activity alongside phenolic contents of ethanolic and methanolic extracts of plants collected from two different localities (rocky slopes and private garden). Additionally, the antiproliferative/cytotoxic activity of these extracts on the human cervix adenocarcinoma HeLa S3 cell line was includ- ed in this study, due to the fact that rue is well-known traditional uterine remedy (PDR, 2000; TASIĆ et al., 2004; TUCAKOV, 1997). Therefore the study sought to elucidate the impact of plant growth conditions and geographical location on these properties. Material and methods General Plant materials were collected from Ruta graveolens L. (Rutaceae) in 2007 at two different locations: 1) Sićevačka gorge, Sićevo (E Serbia), cca. 590 m a.s.l., rocky and bushy slopes at the limestone ground; GPS Coordinates: 43°20’34.60”N; 22°6’30.79”E; 2) Niš (Novo selo), (SE Serbia), cca. 180 m a.s.l., cultivated in the garden; GPS Coordinates: 43°19’3.39”N; 21°48’44.41”E. The aerial parts of the wild growing and cultivated plants were collected at the beginning of the fowering season and the aerial parts of the wild growing plants were also collected at the end of the fowering sea- son. The plant was identifed and authenticated by the taxonomist Dr. Bojan Zlatković. The voucher herbarium specimens (accession number 3106 HFF) have been deposited in the Herbarium collection of the Faculty of Pharmacy, University of Belgrade. The plant material was reduced to a fne powder and extracted with ethanol (70 %, v/v) or methanol (80 %, v/v) by percolation, as described in European Pharmacopeia 6.0. 10 (Ph. Eur. 6.0, 2007). Ethanolic and methanolic extracts of wild growing plants collected at the beginning (RE and RM) and at the end of the fowering season (R2E and R2M), and of cultured plants (RDE and RDM) were ob- tained after evaporation to the dryness under reduced pressure below 40 ºC. The reference chemicals such as rutin and catechin used for calibra- tion curves were purchased from Sigma-Aldrich (St. Louis, USA), CORE Metadata, citation and similar papers at core.ac.uk Provided by JKI Open Journal Systems (Julius Kühn-Institut)