Cenk Durmuşkahya

Evaluation of linden fibre as a potential reinforcement material for polymer composites

The aim of this study is to characterize linden fibres as a novel cellulose-based fibre to be used as a reinforcement material in composites and to investigate the adhesion property to unsaturated polyester. Up to now, there is no report regarding the potential usability of linden fibre in composite applications. Linden fibres were extracted from the stem of a plant of Tilia rubra DC. subsp. caucasica (Rupr.) V.Engl. Characterization of linden fibres was studied by Fourier transform infrared, X-ray photoelectron spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, tensile and pull-out tests. Morphological properties of the fibres were observed through scanning electron and optical microscopes. Initial degradation temperature of the linden fibre was reported to be 238℃. The tensile strength and the Young’s modulus of the linden fibres were calculated to be 675.4 ± 45.7 MPa and 61.0 ± 9.8 GPa, respectively. The interfacial shear strength of the linden fibre with unsaturated polyester matrix was computed as 26.15 ± 2.27 MPa via pullout test. This study offers an alternative and eco-friendly reinforcement material which may have usability potential in polymeric composites.

Effect of Extracts of the Endemic Plants Centaurea lydia and Phlomis nissolii on Toxoplasma gondii

OBJECTIVE This study aimed to investigate the potential antitoxoplasma activities of extracts of the endemic plants Centaurea lydia and Phlomis nissolii in a fibroblast cell culture infected with T. gondii trophozoites. METHODS WI-38 cell lines treated with plant extracts (55 μg/mL each) and an untreated control were infected with 5×105 T. gondii trophozoites, and the number of parasites in the medium was determined on days 7, 14, and 24. RESULTS No cytotoxic effects of C. lydia and P. nissolii extracts were detected at concentrations of 0.86-55 μg/mL in the WI-38 cell line, and the absence of the cytotoxicity of these extracts on the fibroblast cell line was considered as a positive effect. C. lydia extract at 55 μg/mL had marked activity against T. gondii trophozoites. A 47.5-fold increase was observed in the number of trophozoites in the control group, while a 84-fold decrease was found in the C. lydia extract group. However, a 36-fold increase was detected in the P. nissolii extract group, indicating no antitoxoplasma activity. CONCLUSION The extract of C. lydia, an endemic plant, was found to be a good drug candidate for treating toxoplasmosis. The in vitro activity of the extract of this endemic plant should be further investigated in animal models in vivo.