Parameter optimization of the SPME technique for the purpose of evaluating the aroma of the fruit of cucumber of transgenic lines with a gene of thaumatin II

Mikroekstrakcja do fazy stałej (SPME) jest nowoczesną techniką izolacji związków lotnych i może stanowić alternatywę dla metod tradycyjnych. Była ona z powodzeniem stosowana w analizie różnych surowców roślinnych i produktów spożywczych. Przedmiotem zainteresowania autorów był aromat transgenicznego ogórka modyfikowanego genem taumatyny II. Do tej pory nie publikowano wyników badań oceniających wpływ tego typu modyfikacji genetycznej na profil zapachowy surowca. Celem pracy był dobór parametrów techniki SPME do oceny aromatu ogórka. Optymalizacja parametrów techniki SPME obejmowała wybór: rodzaju włókna, temperatury, czasu ekstrakcji i wysalania próby. Zastosowanie SPME pozwoliło na identyfikację związków lotnych odpowiedzialnych za aromat ogórka. Ponadto zaobserwowano zróżnicowanie ilościowe zawartości związków lotnych pomiędzy liniami transgenicznymi a niemodyfikowaną linią kontrolną.Solid phase microextraction (SPME) is a modern technique to isolate volatile compounds and it can be an alternative to traditional methods. It was successfully applied to analyse different plant fruit and food products. The authors of this paper focused their attention on the aroma of transgenic cucumber modified using a gene of thaumatin II. Until now, no results have been published of any studies dealing with the evaluation of the effect of this type of genetic modification on the volatile profile of raw material. The objective of this study was to select parameters of the SPME technique for evaluating the aroma of cucumber. The parameter optimization of the SPME technique comprised the selection of: type of fibre, temperature, extraction time, and salting out the sample. Owing to the application of the SPME technique, it was possible to identify volatile compounds responsible for the aroma of cucumber. Moreover, it was found that the contents of volatile compounds in the fruit of transgenic lines and in the non-modified control line differed

An adequate mathematical model of four-rotor flying robot in the context of control simulations

In this paper a model of the dynamics of four-rotor flying robot is described in details. Control design must be preceded by the modeling and subsequent analysis of the robot behavior in simulator. It is therefore necessary to develop the mathematical model as accurate as it is possible. The paper contains a detailed derivation of the mathematical model in the context of physics laws affecting the quadrocopter. The novelty of presented notation is an extention of Coriolis forces in linear acceleration and the gyroscopic effect on angular acceleration. In the validation phase, the mathematical model was verified with the use of proposed control algorithms. Simulation studies have demonstrated the adequacy of a MATLAB model to properly reflect the real quadrocopter dynamics. This would allow for its use in the simulator and afterwards to implement and verify of control laws on the real fourrotor flying robot

Titanium Dioxide Nanoparticles in Food and Personal Care Products—What Do We Know about Their Safety?

Titanium dioxide (TiO2) is a material of diverse applications commonly used as a food additive or cosmetic ingredient. Its prevalence in products of everyday use, especially in nanosize, raises concerns about safety. Current findings on the safety of titanium dioxide nanoparticles (TiO2 NPs) used as a food additive or a sunscreen compound are reviewed and systematized in this publication. Although some studies state that TiO2 NPs are not harmful to humans through ingestion or via dermal exposure, there is a considerable number of data that demonstrated their toxic effects in animal models. The final agreement on the safety of this nanomaterial has not yet been reached among researchers. There is also a lack of official, standardized guidelines for thorough characterization of TiO2 NPs in food and cosmetic products, provided by international authorities. Recent advances in the application of ‘green-synthesized’ TiO2 NPs, as well as comparative studies of the properties of ‘biogenic’ and ‘traditional’ nanoparticles, are presented. To conclude, perspectives and directions for further studies on the toxicity of TiO2 NPs are proposed

Nanocomposites of Titanium Dioxide and Peripherally Substituted Phthalocyanines for the Photocatalytic Degradation of Sulfamethoxazole.

peer reviewedPhthalocyanines (Pcs) are often used in photosensitization of titanium(IV) oxide, a commonly employed photocatalyst, as such an approach holds the promise of obtaining highly stable and efficient visible light-harvesting materials. Herein, we report on the preparation, characterization and photoactivity of a series of composites based on TiO2 and peripherally modified metallophthalocyanines: either tetrasulfonated or 4,4′,4′′,4′′′-tetraazaphthalocyanines, with either copper(II), nickel(II) or zinc(II) as the central metal ion. Physicochemical characterization was performed using UV-Vis diffuse reflectance spectroscopy, hydrodynamic particle-size analysis, surface-area analysis using N2 adsorption-desorption measurements and thermogravimetry combined with differential scanning calorimetry. The band-gap energy values were lower for the composites with peripherally modified phthalocyanines than for the commercial TiO2 P25 or the unsubstituted zinc(II) phthalocyanine-grafted TiO2. TG–DSC results confirmed that the chemical deposition, used for the preparation of Pc/TiO2 composites, is a simple and efficient method for TiO2 surface modification, as all the Pc load was successfully grafted on TiO2. The photocatalytic potential of the Pc/TiO2 materials was assessed in the photocatalytic removal of sulfamethoxazole—a commonly used antibacterial drug of emerging ecological concern. To compare the activity of the materials in different conditions, photodegradation tests were conducted both in water and in an organic medium