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Öğe Biological Activity of Extracts of Traditional Wild Medicinal Plants from the Balkan Peninsula(ELSEVIER, 2019) Vujanovic, Milena; Zengin, Gökhan; Durovic, Saša; Maskovic, Pavle; Cvetanovic, Aleksandra; Radojkovic, MarijaThe aim of the present study was to investigate antioxidant, cytotoxic and enzyme-inhibitory activities of wild growing medicinal herbs in the Balkan Peninsula (Morus nigra L., Symphytum officinale L., Sambucus nigra L., Teucrium chamaedrys L. and Teucrium montanum L.). Notably, antioxidant activity of investigated plant species was confirmed through several assays including free radical scavenging (ABTS), reducing power (CUPRAC), phosphomolybdenum and metal chelating test. Cytotoxic activity was evaluated using three different cell lines: Hep2c, RD and L2OB. S. officinale L. and S. nigra L. showed the highest cytotoxic activity. All studied extracts exhibited remarkable inhibitory effects on tested enzymes. S. nigra L. and T. chamaedrys L. exhibited the strongest tyrosinase inhibitory effects (26.62 +/- 0.77 extract and 14.72 +/- 0.41 mgKAEs/g, respectively), while S. officinale L. was the most potent in terms on a-glucosidase inhibition (11.47 +/- 0.05 mmol ACAE/g extract). The obtained results indicate that the extracts of the tested wild grown plants could be used which can be explored as natural medicines for the promotion of health. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.Öğe Chemical and biological insights on aronia stems extracts obtained by different extraction techniques: From wastes to functional products(ELSEVIER SCIENCE BV, 2017) Cvetanovic, Aleksandra; Svarc-Gajic, Jaroslava; Zekovic, Zoran; Maskovic, Pavle; Durovic, Sasa; Zengin, Gokhan; Delerue-Matos, CristinaThe present study aimed to evaluate chemical and biological potential of aronia stems for providing new raw material for food and pharmaceutical industries. Aqueous extracts of aronia stems were prepared by three different techniques (microwave-assisted, ultrasound-assisted and subcritical water extraction). For biological activities, antioxidant, antimicrobial and cytotoxic activities were evaluated. For chemical characterisation, phenolic compounds and essential elements were analysed as well as total phenolic contents. Subcritical water extracts exhibited the strongest antioxidant activity with the highest content of phenolics. Minimum inhibitory concentrations for analysed extracts were in the range from 9.76 to 156.25 mu g/mL in antimicrobial assays. The extracts exerted prominent cytotoxicity against different cell lines. Rutin was detected as the major compound in the studied extracts and these extracts were also rich in essential elements. Our study suggested that subcritical water extract of aronia stem could be considered as a new raw material in developing novel functional/industrial products.Öğe Effects of Orange Leaves Extraction Conditions on Antioxidant and Phenolic Content: Optimization Using Response Surface Methodology(TAYLOR & FRANCIS INC, 2018) Uysal, Şengül; Cvetanovic, Aleksandra; Zengin, Gökhan; Durovic, Sasa; Zekovic, Zoran; Aktümsek, AbdurrahmanIn the last few years, bioactive components or their extraction techniques are gaining special interest in scientific areas. In this framework, orange leaves were used for preparation of extracts with high content of biologically active compounds. To optimize the extraction process, three levels and three variables of Box-Behnken design with response surface methodology were applied. Investigated responses were the total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, cupric ion reducing antioxidant capacity (CUPRAC), and ferric reducing antioxidant power (FRAP). Independent variables were methanol concentration (10-90%), temperature (20-60 degrees C), and extraction time (60-180min). Experimentally obtained results were fit into a second-order polynomial model with multiple regression. Analysis of variance was used to estimate model fitness and determine optimal conditions for processing. Estimated optimal conditions were 90% methanolic solution, 60 degrees C and 180min using these parameters; the predicted values of investigated responses were 43.19mg GAE/g (GAE: gallic acid equivalents), 43.04mg TE/g (TE: trolox equivalents), 139.34 and 93.76mg TE/g for TPC, DPPH, CUPRAC, and FRAP, respectively. The obtained optimal conditions could be considered as an alternative strategy for developing novel functional products.Öğe Influence of different extraction techniques on the chemical profile and biological properties of Anthemis cotula L.: Multifunctional aspects for potential pharmaceutical applications(ELSEVIER SCIENCE BV, 2019) Sut, Stefania; Dall'Acqua, Stefano; Zengin, Gokhan; Senkardes, Ismail; Bulut, Gizem; Cvetanovic, Aleksandra; Stupar, Alena; Mandić, Anamarija; Picot-Allain, Carene; Dogan, Ahmet; Sinan, Kouadio Ibrahime; Mahomoodally, FawziThe phytochemical composition of different extracts obtained from stinking chamomile (Anthemis cotula L) was investigated. Ethanol was used as solvent and accelerated solvent extraction (ASE), microwave assisted extraction (MAE), maceration, soxhlet extraction (SE), and ultrasound assisted extraction (UAE) were applied on plant material. Comparison of the phytochemical contents, antioxidant, and enzyme inhibitory properties were performed. The most abundant sesquiterpene in the extracts was anthecotuloide, while the most present phenolics were caffeoyl quinic acid, quercetin, and kaempferol derivatives. UAE extract was the most efficient in the extraction of sesquiterpenoids and polyphenols. Considering the assays on antioxidant activity and enzyme inhibition, ASE extract showed highest phenolic content (62.92 mg gallic acid equivalent/g extract). Likewise, this extract showed highest radical scavenging (103.44 mg trolox equivalent [TE]/g extract and 155.70 mg TE/g extract, for DPPH and ABTS assays respectively) and reducing power potential (435.32 and 317.89 mg TE/g extract, for CUPRAC and FRAP assays, respectively). The different extracts showed similar results in the enzyme inhibition assays suggesting that the extraction methods used have no effect on observed enzyme activities. Novelty of our findings are the inhibitory action of the ethanol extract of A. cotula aerial parts on key enzymes associated with Alzheimer's disease (acetyl cholinesterase, butyryl cholinesterase), type 2 diabetes (alpha-amylase, alpha-glucosidase), and skin hyperpigmentation disorders (tyrosinase). Data collected from the present work further appraises the multiple potential biological properties of stinking chamomile suggesting the need for further investigation on its constituents. (C) 2019 Elsevier B.V. All rights reserved.Öğe The influence of the extraction temperature on polyphenolic profiles and bioactivity of chamomile (Matricaria chamomilla L.) subcritical water extracts(ELSEVIER SCI LTD, 2019) Cvetanovic, Aleksandra; Svarc-Gajic, Jaroslava; Zekovic, Zoran; Jerkovic, Jelena; Zengin, Gokhan; Gasic, Urog; Tesic, Zivoslav; Mašković, Pavle; Soares, Cristina; Barroso, M. Fatima; Delerue-Matos, Cristina; Đurović, SašaThe main goal of this research was to determine the relationship among chemical structure, bioactivity and temperature of chamomile during subcritical water extraction in isobaric conditions (45 bar) at seven different temperatures (65-210 degrees C). The influence of temperature on phenolic profiles was defined by UHPLC-HESI-MS/MS. The overall results indicate that the presence of conjugated double bonds, side chains, glucose moiety or ether moiety in molecules influence the efficiency of polyphenols' extraction in subcritical water. In terms of antioxidant activity, the extracts were the most active towards ABTS radicals (IC50 = 7.3-16.8 mu g/mL), whereby temperature of 150 degrees C was optimal. On the other hand, the extracts obtained at 115 degrees C showed highest cytotoxicity. Inhibition of alpha-amylase and alpha-glucosidase was the highest at 65 and 85 degrees C, i.e. 0.51 and 4.13 mmolAE/g, respectively. Activity against tyrosinase was the highest at 210 degrees C (17.92 mgKAE/g). The data showed that different non-phenolic compounds may also participate in bio-activities of the extracts.Öğe Isolation of apigenin from subcritical water extracts: Optimization of the process(ELSEVIER SCIENCE BV, 2017) Cvetanovic, Aleksandra; Svarc-Gajic, Jaroslava; Gasic, Uros; Tesic, Zivoslav; Zengin, Gokhan; Zekovic, Zoran; Durovic, SasaApigenin is a phytochemical which has been associated with numerous beneficial health effects. However, due to its low concentration and poor bioavailability, isolation from natural sources is very difficult. Subcritical water (SCW) is an excellent solvent for the extraction of moderately polar and non-polar flavonoids. Carefully balanced moderate hydrolytical potential of SCW was used in this work to liberate apigenin from its bound forms. In this research simultaneous extraction and hydrolysis of apigenin bound forms from chamomile have been performed. Optimal operation parameters for maximum yields of apigenin have been investigated and defined (solvent-to-sample ratio 1:30; agitation rate 3 Hz; pressure 45 bar; temperature 115 degrees C; time 30 min). Apigenin was further isolated in its pure form from water extracts obtained under optimal conditions using column chromatography. The purity of isolated compound was confirmed by spectroscopic analysis. Biological activity of extracts obtained under optimal conditions were determined as well. In order to identify polyphenolic compounds UHPLC-HESI-MS/MS analysis was performed. (C) 2016 Elsevier B.V. All rights reserved.Öğe Metabolomic profile of Salvia viridis L. root extracts using HPLC-MS/MS technique and their pharmacological properties: A comparative study(ELSEVIER SCIENCE BV, 2019) Zengin, Gokhan; Mahomoodally, Fawzi; Picot-Allain, Carene; Diuzheva, Alina; Jeko, Jozsef; Cziaky, Zoltan; Cvetanovic, Aleksandra; Aktumsek, Abdurrahman; Zeković, Zoran; Rengasamy, Kannan R.R.Several Salvia species have received due scientific attention regarding their therapeutic virtues, yet little is known about the pharmacological potential of Salvia viridis L. roots. This study, therefore, attempts to explore the phytochemical composition, enzyme inhibitory potential, and antioxidant activities of S. viridis ethanolic root extracts obtained by different extraction methods, namely microwave-assisted extraction, maceration, supercritical fluid extraction, Soxhlet extraction, and ultrasonic assisted extraction. The extract produced by ultrasonic assisted extraction possessed the highest phenolic and flavonoid contents (111.41 mg gallic acid equivalent/g extract and 23.46 mg rutin equivalent/g extract). S. viridis ethanolic root extract obtained by ultrasonic assisted extraction showed highest radical scavenging (240.00 and 302.85 mg Trolox equivalent TE/g for DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid) assays, respectively) and reducing (970.74, 704.27 mg TE/g, and 2.84 mmol TE/g for CUPRAC (cupric reducing antioxidant capacity), FRAP (ferric reducing antioxidant power), and phosphomolybdenum assays, respectively) activities. Chemical profiles of these extracts were investigated by HPLC MS/MS, and the profiles (23 components) of the supercritical fluid extract was different from other extraction techniques. The study reports for the first time, the inhibitory action of ethanolic root extract of S. viridis on key enzymes related to Alzheimer's disease (acetylcholinesterase, butyrylcholinesterase), diabetes (a-amylase, a-glucosidase), and skin hyperpigmentation disorders (tyrosinase). Data generated from this study appraises the multiple biological activities of plants belonging to the Salvia genus. Scientific evidence gathered in this study support further investigations which might lead to the development of new pharmaceutical entities for the management of diabetes, Alzheimer's disease, and skin hyperpigmentation conditions.Öğe Multidirectional Approaches on Autofermented Chamomile Ligulate Flowers: Antioxidant, Antimicrobial, Cytotoxic and Enzyme Inhibitory Effects(ELSEVIER, 2019) Cvetanovic, Aleksandra; Zekovic, Zoran; Zengin, Gökhan; Maskovic, Pavle; Petronijevic, Mirjana; Radojkovic, MarijaIn the frame of the present paper the enzymatic transformation of apigenin-glucosides into free aglycone was achieved by autofermentation of chamomile ligulate flowers (CLF). Antioxidant properties of the autofermented CLF (A-CLF) extract were evaluated by their radical scavenging activity against hydroxyl radicals and inhibition of lipid peroxidation. Obtained results showed that A-CLF extract in a concentration of 0.84 mg/mL was able to inhibit 50% of hydroxyl radicals, while IC50 value in the case of inhibition of lipid peroxidation was 5.21 mg/mL. Antimicrobial activity was done by measuring minimal inhibitory concentration (MIC) values for eight microbial strains. Obtained MIC values (9.75-156.25 mu g/mL) confirmed high antibacterial and antifungal activities of the extract. Cytotoxic activity was done by using three histological different cell lines: Hep2C; RD and L2OB. Obtained IC50 values for these cell lines were: 28.72; 17.31 and 10.92, respectively. Furthermore, in vitro investigation of the A-CLF ability to inhibit selected enzymes (alpha-amylase, alpha-glucosidase, tyrosinase) was done as well. Determined activities against alpha-amylase and alpha-glucosidase were 0.94 and 3.24 mmol ACAE/g, respectively. Further, measured activity against tyrosinase was 0.69 mg KAEs/g indicating high enzyme-inhibitory activity of examined sample. Results demonstrated that A-CLF extracts showed considerable pharmacological activity. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.Öğe A new source for developing multi-functional products: biological and chemical perspectives on subcritical water extracts of Sambucus ebulus L.(WILEY, 2018) Cvetanovic, Aleksandra; Zekovic, Zoran; Svarc-Gajic, Jaroslava; Razic, Slavica; Damjanovic, Ana; Zengin, Gokhan; Delerue-Matos, CristinaBACKGROUND: To obtain bioactive fractions from plant material subcritical water is notably advantageous in comparison to any other technique. Excellent solvating properties and selectivity combined with finely tuned reactivity of subcritical water enable exploitation of the potential of plants. Herein subcritical water extraction was used for recovery of bioactive compounds from leaves, roots and fruits of Sambucus ebulus L. Extracts obtained were characterized in terms of biological and chemical fingerprints. RESULTS AND DISCUSSIONR: esults obtained by using several antioxidant assays that focused on different mechanisms showed that subcritical water extracts of Sambucus ebulus were powerful antioxidants. Enzyme inhibitory effects were tested against alpha-amylase, alpha-glucosidase and tyrosinase, and the results showed the anti-diabetic potential of the extracts as well as its possible use with skin disorders. Antiproliferative properties were detected on three cell lines (A-549; LS-174 T; HeLa) and showed prominent cytotoxicity against all tumor cell lines. Inhibitory concentrations obtained were in the range 0.58-8.10 mu g mL(-1). Generally, the SCW extracts from leaves exhibited stronger biological activities with higher levels of phenolic compounds compared with the roots and fruits of Sambucus ebulus. Gallic acid, catechin and caffeic acid were identified as major components in these extracts and these components seem to relate with observed biological activity. CONCLUSION: The results obtained suggest that Sambucus ebulus has great potential for preparing new phyto-pharmaceuticals and functional food ingredients. (C) 2017 Society of Chemical Industry.Öğe Optimization of maceration conditions for improving the extraction of phenolic compounds and antioxidant effects of Momordica Charantia L. leaves through response surface methodology (RSM) and artificial neural networks (ANNs)(TAYLOR & FRANCIS INC, 2019) Uysal, Şengül; Cvetanovic, Aleksandra; Zengin, Gökhan; Zekovic, Zoran; Mahomoodally, Mohamad Fawzi; Bera, OskarThe main goals of this research were the chemical and biological characterization of the bitter melon (Momordica charantia) isolate obtained by traditional (maceration) extraction, as well as optimization of this process using response surface methodology (RSM) and artificial neural networks (ANNs). Experiments were performed using Box-Behnken experimental design on three levels and three variables: extraction temperature (20 degrees C, 40 degrees C, and 60 degrees C), solvent concentration (30%, 50%, and 70%) and extraction time (30, 60, and 90 min). The measurements consisted of 15 randomized runs with 3 replicates in a central point. The antioxidant activity of obtained extracts was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH), cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays while chemical characterization was done in terms of the total phenolic content (TPC). The methodology shows positive influence of solvent concentration on all four observed outputs, while temperature showed a negative impact. RSM showed that the optimal extraction conditions were 20 degrees C, 70% methanol, and an extraction time of 52.2 min. Under these conditions, the TPCs were 20.66 milligrams of gallic acid equivalents (mg GAE/g extract), DPPH 30.22 milligrams of trolox equivalents (mg TE/g extract), CUPRAC 67.78 milligrams of trolox equivalents (mg TE/g extract), and FRAP 45.48 milligrams of trolox equivalents (mg TE/g extract). The neural network coupled with genetic algorithms (ANN-GA) was also used to optimize the conditions for each of the outputs separately. It is anticipated that results reported herein will establish baseline data and also demonstrate that that the present model can be applied in the food and pharmaceutical industries.Öğe Optimization of the extraction process of antioxidants from loquat leaves using response surface methodology(WILEY, 2017) Uysal, Şengül; Cvetanovic, Aleksandra; Zengin, Gökhan; Durovic, Sasa; Aktümsek, AbdurrahmanThis study is designed to optimize the extraction of polyphenolics and antioxidant potential of loquat leaves using response surface methodology (RSM). Three levels and three variables Box-Behnken experimental design in combination with RSM was applied. Independent variables were solvent concentration (10-90%), temperature (20-60 degrees C) and time (60-180 min), while investigated response was total phenolic content as well as antioxidant activity. The experimental results were fitted to a second-order quadratic polynomial model, and they showed a good fit to the proposed model. In order to assess model fitness and determine optimal conditions, for maximal phenolic content and antioxidant activity, analysis of variance was employed. Determined optimized conditions for maximizing yield of antioxidant compounds were within the experimental range: ethanol concentration of 88.4%, extraction temperature of 28 degrees C, extraction time of 70.8 min. Under these conditions, the predicted maximum values were TP-77.18 mg GAE/g, DPPH-80.42 mg TE/g, CUPRAC-308.87 mg TE/g and FRAP-164.12 mg TE/g. Practical applicationsPlant phenolics have remarkable biological activities including antioxidant, antimicrobial and anticancer. Therefore, their extraction techniques have gained more attention in recent years. This study was designed to detect optimal extraction conditions of independent factors (i.e. solvent concentration, temperature and time) in order to obtain the highest yields of phenolics from loquat leaves as well as antioxidant activity. This study could be valuable for designing new nutraceutical and functional food ingredients in terms of high recovery of phenolics from loquat leaves.Öğe Optimization of the Extraction Process of Antioxidants from Orange Using Response Surface Methodology(SPRINGER, 2016) Maskovic, Pavle Z.; Diamanto, Lazari D.; Cvetanovic, Aleksandra; Radojkovic, Marija; Spasojevic, Miroslav B.; Zengin, GokhanDifferent extraction conditions may significantly influence extraction of particular compound groups. In the present study, response surface methodology (RSM) based on Box-Behnken design was used to define the best combination of extraction temperature (20-60 A degrees C), ethanol concentration (10-90 %) and extraction time (60-180 min) for maximum yield of antioxidant compounds and maximum antioxidant activity of orange extracts. Experimental values of total phenol yields were in the range from 3.10 to 3.72 mgGAE/ml, while total flavonoid content was in the range from 1.42 to 2.13 mgRE/ml. Antioxidant activity expressed as the 50 % inhibition concentration (IC50 value) was in the range from 0.03 to 0.04 mg/ml. The experimental results were fitted to a second-order quadratic polynomial model, and they have shown a good fit to the proposed model (R (2) > 0.90). Determined optimized conditions for maximizing yield of antioxidant compounds were within the experimental range.Öğe Tamarindus indica L. Seed: Optimization of maceration extraction recovery of tannins(SPRINGER, 2020) Cvetanovic, Aleksandra; Uysal, Şengül; Pavlic, Branimir; Sinan, Kouadio Ibrahime; Llorent-Martinez, Eulogio J.; Zengin, GökhanThe seeds of Tamarindus indica L., classified as bio-waste, are powerful sources of bioactive compounds, especially tannins. In order to use its full potential, extraction of such bioactive constituents should be done under the optimized conditions. In the frame of this paper, central-composite experimental design and RSM (response surface methodology) were applied in order to investigate the impact of the maceration parameters on target responses and to optimize extraction process. Extraction was performed under the different levels of extraction solvent (methanol), temperature, and solvent-to-sample ratio. Obtained extracts were evaluated in terms of total phenols, flavanols, and tannin yield and in vitro antioxidant activity (DPPH, FRAP, CUPRAC). Experimental results were fitted to a second-order polynomial model where regression analysis and analysis of variance were used to determine model fitness and optimal extraction conditions. Optimized extraction conditions determined by RSM were methanol concentration of 69.99%, extraction temperature of 23.38 degrees C, solvent-to-sample ratio of 1:20. Chemical characterization of the extract obtained under the optimized conditions was done by using HPLC-ESI-MS/MS technique. The study could provide a scientific baseline for designing novel functional products from T. indica seeds in further studies.