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Ionic liquids bring a promise of a wide range of "green" applications that could replace conventional volatile solvents. However, before these applications become large-scale, their toxicity needs to be investigated in order to predict the impact on human health and environment. In this study we assessed the cytotoxicity of imidazolium ionic liquids (in the concentrations between 0.1 mmol L -1 and 10 mmol L -1 ) in the ovarian fi sh cell line CCO and the human tumour cell line HeLa using the MTT cell viability assay. Our results showed that the most cytotoxic ionic liquid was 1-n-butyl-3-methylimidazolium bis(trifl uoro methylsulphonyl)imide, [BMIM][Tf 2 N], followed by 1-n-butyl-3-methylimidazolium tetrafl uoroborate [BMIM] [BF 4 ], 1-n-butyl-3-methylimidazolium hexafluorophosphate [BMIM] [PF 6 ], and 1,3-dimethylimidazolium hexafl uorophosphate [MMIM] [PF 6 ]. Generally, the effects were concentrationdependent. They also depended on the type of anion and the n-alkyl chain length. The comparison between the fi sh CCO and human HeLa cell lines suggests that CCO cells provide a good biological system for initial toxicity testing of ionic liquids that could replace in vivo bioassays.

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The effect of independent variables of microwave-assisted extraction (MAE), extraction temperature (50-90°C), microwave power (100-200 W), solvent concentration (methanol/water, 50-90%, v/v) and extraction time (1-27 min) on total phenolics and flavonoids contents as well as antioxidant activity of broccoli extracts was investigated. Response surface methodology was successfully applied for optimisation and the high correlation of the mathematical model indicated that a quadratic polynomial model could be used for optimisation of investigated responses. Considering the maximum amount of extracted total phenolics, total flavonoids and antioxidant activity expressed as ORAC value, the optimal conditions for all three investigated responses were obtained (temperature À71.11°C; microwave power À167.03 W; solvent concentration À75.95%; and extraction time 16.34 min), which is in agreement with optimal conditions obtained for each investigated responses. The development of simultaneously MAE methods for total phenolics, total flavonoids and antioxidant activity of broccoli extracts might simplify assessment of broccoli as valuables source of antioxidants.

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