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Maria Maliarova, Tibor Maliar, Jana Girmanova, Jozef Lehotay and Jan Kraic

. RAKATOARISON, D.A., GRESSIER, B., TROTIN, F., BRUNET, C., DINE, T., LUYCKS, M., VASSEUR, J., CAZIN, M., CAZIN, J.C., PINKAS, M.: Antioxidant activities of polyphenolic extracts from flowers, in vitro callus and cell suspension cultures of Crataegus monogyna . Pharmacol. 57, 1997, 60-63. ROTHWELL, J.A., DAY, A.J., MORGAN, M.R.A.: Experimental Determination of Octanol - Water Partition Coefficients of Quercetin and Related Flavonoids. J.Agric Food Chem. 53, 2005, 4355 - 4360. SCHMITT, M., HARBECK, M., THOMSSEN, C., WILHELM, O., MAGDOLEN, V

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Dasa Kruzlicova, Martina Danihelova and Miroslav Veverka

external validation techniques. J. Chemometr., 24, 2010, 194-201. DAWIDOWICZ, A.L., WIANOWSKA, D., OLSZOWY, M.: On practical problems in estimation of antioxidant activity of compounds by DPPH method (Problems in estimation of antioxidant activity). Food Chem., 131, 2012, 1037-1043. DUTHIE, S.J., COLLINS, A.R., DUTHIE, G.G., DOBSON, V.L.: Quercetin and myricetin protect against hydrogen peroxide-induced DNA damage (strand breaks and oxidised pyrimidines) in human lymphocytes. Mutat. Res., 393, 1997, 223

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Ioanna Karageorgou, Spyros Grigorakis, Stavros Lalas and Dimitris P. Makris

Abbreviations HBA, hydrogen bond acceptor HBD, hydrogen bond donor HP- β -CD, 2-hydroxypropyl β -cyclodextrin LTTM, vlow-transition temperature mixture MoL, M. oleifera leaves References Alvarez-Parrilla E, Laura A, Torres-Rivas F, Rodrigo-Garcia J, González-Aguilar GA (2005) Complexation of apple antioxidants: chlorogenic acid, quercetin and rutin by β -cyclodextrin ( β -CD). J. Inclus. Phenom. Macrocycl. Chem. 53: 121-129. Bi W, Tian M, Row KH (2013) Evaluation of alcohol-based deep eutectic solvent in extraction and

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Agata Zdyb and Stanisław Krawczyk

;5:2112-2122. DOI: 10.1016/j.matpr.2017.09.208. [15] Zdyb A, Krawczyk S. Adsorption and electronic states of morin on TiO 2 nanoparticles. Chem Phys. 2014;443:61-66. DOI: 10.1016/j.chemphys.2014.08.009. [16] Zdyb A, Krawczyk S. Characterization of adsorption and electronic excited states of quercetin on titanium dioxide nanoparticles. Spectrochim Acta Part A: Mol Biomol Spectrosc. 2016;157:197-203. DOI: 10.1016/j.saa.2016.01.006. [17] Kamat PV, Bedja I, Hotchandani S. Photoinduced charge transfer between carbon and semiconductor clusters. One-electron reduction

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Henryk Dębski, Wiesław Wiczkowski, Dorota Szawara-Nowak, Natalia Bączek, Małgorzata Piechota and Marcin Horbowicz

Abstract

Tropospheric ozone forms in photochemical reactions or by refuse burning and combustion of exhaust gases from engines, and during some industrial processes. The mean ambient ozone concentration doubled during the last century, and in many urban areas has reached the phytotoxic level. In the present study, there was determined the effect of ozone fumigation on levels of individual flavonoids, chlorophylls, carotenoids and total phenols in the cotyledons of four common buckwheat cultivars (Hruszowska, Panda, Kora and Red Corolla). Six-day-old buckwheat seedlings were grown in controlled conditions and treated with an elevated dose of ozone (391 μg · m−3) during 5 days for 1 h each day. After the experiment, the cotyledons of the seedlings were analysed for individual flavonoids, chlorophylls, carotenoids and total phenols. Shoot elongation was also measured. Individual types of flavonoids in buckwheat cotyledons were found to respond to an elevated ozone dose in various ways. The response was also dependent on the cultivar evaluated. In the cotyledons of ozonized buckwheat seedlings, contents of C-glucosides of luteolin and apigenin decreased or did not change depending on the cultivar examined. In the case of flavonols, the contents of quercetin-3-O-rhamnosyl-galactoside and rutin (quercetin-3-O-rhamnosyl-glucoside) were markedly reduced in most cultivars. O3 had no effect on the level of anthocyanins and chlorophylls but it decreased carotenoids, and tended to inhibit buckwheat growth. In conclusion, a thesis can be formulated that, due to high reduction in important flavonoids, an elevated level of ambient ozone decreases the nutritional value of common buckwheat seedlings.

Open access

Katarína Hroboňová, Andrea Špačková and Martina Ondáková

determination of coumarins from complex samples. J. Pharm. Biomed. Anal. 145: 144-150. Machyňáková A, Hroboňová K (2017b) Synthesis and evaluation of molecularly imprinted polymers as sorbents for selective extraction of coumarins. Chromatographia 80: 1015-1024. Molinelli A, Weiss R, Mizaikoff B (2002) Advanced solid-phase extraction using molecularly imprinted polymers for the determination of quercetin in red wine. J. Agric. Food Chem. 50: 1804-1808. Ribéreau-Gayon P, Glories Y, Maujean A, Dubourdieu D (2006) Handbook of Enology, Volume 2: The Chemistry of

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Ottó Dóka, Andrea Brunori, Rezső Schmidt, Dane Bicanic and György Végvári

dietary rutin and quercetin. J. Agr. Food Chem. 51: 6452-6455. Gupta N, Sharma SK, Rana JC, Chauhan RS (2011) Expression of flavonoid biosynthesis genes vis-a-vis rutin content variation in different growth stages of Fagopyrum species. J. Plant Physiol. 168: 2117-2123. Giménez-Bastida JA, Zieliński H (2015) Buckwheat as a functional food and its effects on health. J. Agr. Food Chem. 63: 7896-7913. He J, Klag MJ, Whelton PK, Mo JP, Chen JY, Qian MG, Mo PS, He GQ (1995) Oats and buckwheat intake and cardiovascular disease

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Ng Boon Swan and Muhammad Abbas Ahmad Zaini

;219:88-94. DOI: 10.1016/j.molliq.2016.02.096. [45] Lei C, Pi M, Zhou W, Guo Y, Zhang F, Qin J. Synthesis of hierarchical porous flower-like ZnO-AlOOH structures and their applications in adsorption of congo red. Chem Phys Lett. 2017;687:143-151. DOI: 10.1016/j.cplett.2017.09.018. [46] Satheesh R, Vignesh K, Rajarajan M, Suganthi A, Sreekantan S, Kang M, et al. Removal of congo red from water using quercetin modified α-Fe 2 O 3 nanoparticles as effective nanoadsorbent. Mater Chem Phys. 2016;180:53-65. DOI: 10.1016/j.matchemphys.2016.05.029. [47] Tran HN, You

Open access

Ouroud Fellah, Samir Hameurlaine, Noureddine Gherraf, Amar Zellagui, Tahar Ali, Abdennabi Abidi, Muhammed Altun, Ibrahim Demirtas and Ayse SahinYaglioglu

Abstract

The aerial parts of T. gallica collected from three different locations (arid, humid and semi-arid) were extracted using ethyl acetate. The crude extracts were subjected to phenolic appraisal and antiproliferative activity using ELISA and xCELLigence assays. The total phenolic and flavonoids were evaluated using appropriate techniques to give a yield of total phenolics ranging between 238.46 and 348.56 mg GAE (Gallic acid equivalent)/g dry weight extract. The flavonoids yield was found to vary from 36.6 to 103.14 mg QE (quercetin equivalent)/g dry weight extract. Moreover, the extracts were tested against rat brain tumor (C6) and human cervix carcinoma (HeLa) cell lines and displayed important differences in activity. These disparities highlighted the effect of climatic factors as quality determinants of secondary metabolites and therefore as a key control of the biological therapeutic effect.

Open access

Ibtissem Boulacel, Brahim Harkati, Radia Ayad, Ibrahim Demirtas, Hocine Laouer and Salah Akkal

Abstract

The focus of this paper was to assess the phytochemical composition, the antioxidant and antibacterial activities of the crude extracts of the aerial parts of Ferula lutea. Four new compounds were isolated from this genus, and their structures were primarily established by extensive spectroscopic analysis including 1D and 2D spectroscopic techniques. Total phenolics and flavonoids containing in ethyl acetate (AcOEt) and n-butanol (n-BuOH) extracts were quantified [199.1-184.02 mg gallic acid equivalent / g of dry weight], flavonoids [70.24-65.95 mg quercetin / g dry weight]. DDPH scavenging and phosphomolybdenum methods were used to evaluate in vitro antioxidant activity. The obtained results showed a significant antioxidant activity of the two aerial parts. Correlation analysis between the DPPH values and those for TAC indicates the possibility of the two models for evaluating antioxidants power from medicinal plants. Dichloromethane (CH2Cl2), AcOEt and n-BuOH extracts were screened against two gram-negative [Escherichia coli (E.coli) and Pseudo aeruginosa (P.aer)] and two gram-positive [Staphylococcus aureus (S.aur) and Bacillus (Bacil.)] bacteria using disc diffusion method. The results indicate a good inhibition of CH2Cl2 and EtAct extracts on the growth of (Bacil. and E.coli). Furthermore n-but extract showed a significant inhibitory effect only against E.coli.