Food additives are chemical substances added to improve organoleptic characteristics, in this context, there are several synthetic dyes, such as sunset yellow, tartrazine, erioglaucine, allura red, indigo carmine, and new coccine, that can also be identified through different analytical techniques such as infrared spectroscopy, UV-Vis spectrophotometry, high performance liquid chromatography with diode array detector and mass spectrometry. Therefore, the objective of this work was to compare methods developed for different analytical techniques, in order to identify the one that presents greater efficiency in certain applications. For this, the patterns of the dyes were analyzed, as well as their mixtures and foods that had them. As a result, the CLAE-DAD presents excellent selectivity and linearity of the calibration curves, but it presents higher LD and LQ values when compared to the UV-Vis, in turn the infrared provides information regarding functional groups and bonds. Mass spectrometry showed great capabilities in identifying the molecular formula and better selectivity in the absence of the erioglaucine dye. It is not feasible to indicate the best or worst analytical approach, but it is possible to point out which one is more suitable for each application. Regarding the quantification capacity, chromatography and UV-Vis are good alternatives, but in mixtures containing more than one dye, CLAE-DAD is more suitable due to the better selectivity. Regarding the identification capacity, mass spectrometry, especially FT-ICR MS, is the most appropriate technique to propose molecular formulas due to its high resolution and mass accuracy. The advantage of FTIR was the easier sample preparation, being able to analyze the dyes in the solid state.

A new method to identify the authenticity of Brazilian banknotes (R$) is proposed using digital image analysis by a smartphone application, Photometrix®, associated with chemometric tools. Authentic banknotes (n = 4) obtained in local bank and falsified (n = 12) by the author himself by means of three printers (laser-Deskjet®, wax-Color Qube® and inkjet-Deskjet®) were used for the development of the methodology. An experimental planning was performed to evaluate the authenticity of the banknotes determining: the best region (holographic band, tactile region in the lower left and right upper number, effigy microimpressions, lower number left, animal figure, watermark and puzzle); Region of Interest (ROI) (16x16; 32x32 and 64x64 pixels), focal length (8, 12, 15 and 20 cm) and variation of the smartphone (Motorola G5 Plus, Samsung S7 and LG K10). The best regions chosen were effigy microimpressions and round the animal. Promising results were obtained from ROI 16x16 pixels with focal length fixed at 10 cm. Thus, the application presents promising features for analyzing the authenticity of banknotes by digital images making it fast, non-destructive, portable, with low cost, and can be accessed by all society.

A methanol-soluble fraction of the dichloromethane extract from the culture broth of A. alternata AT4303 strain afforded the following five known mycotoxins: alternariol, alternariol monomethyl ether, altenusin, altenuene and altertoxin I. A hexane-soluble fraction of the dichloromethane extract yielded the steroids ergosterol and ergosterol peroxide, and alternariol monomethyl ether. The concentrated ethyl acetate extract afforded the nucleoside uridine, uracil and inosine. The micro-extracts obtained from this strain in solid media were analyzed using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS), and the following five known toxins were identified: ACTG-C, D, E and F and AK-toxin II. The major toxins produced by the tangerine pathotype ACT-toxins appear to be absent in strain AT4303. However, the low concentration of ACT-toxins appears to be responsible for their lack of detection in this study. Some compounds isolated from citrus plants were tested for in vitro activity against this strain. The results indicated that 17.3 µM apigenin-7-O-rutinoside inhibited by 80% conidial germination and appressorium development.