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The most common adulterants found in extra-virgin olive oil are refined olive oil and other vegetable oils, such as sunflower, soybean, corn, and canola. In addition to constituting economic fraud, adulteration can cause serious damage to the health of the consumer. This study focuses on the detection and quantification of the adulteration of extra-virgin olive oil with edible oils, using spectrofluorimetry and chemometrics. The data were analyzed by Principal Components Analysis (PCA) and Partial Least Squares (PLS) analysis. Through PCA, it was possible to separate the samples into two distinct areas, olive oil and other edible oils, based on their chemical composition. The PLS model, built with the spectra of mixtures of soybean oil in extra-virgin olive oil, exhibited an R 2 of 0.99412 and low RMSEP (Root Mean Square Error of Prediction) (3.59), RMSEC (Root Mean Square Error of Calibration) (2.32) and bias (4.77. 10 -7 ) values. Thus, the PLS model was considered exact for calibration and prediction.

In this paper, multivariate calibration models have been developed for determination of common adulterants (kerosene, turpentine and residual oil from fried foods) added to diesel. The samples were analyzed by LED spectrofluorimetry and the multivariate calibration models were developed by Partial Least Squares (PLS). The proposal is suggested as an analytical methodology of low-cost, fast and non-destructive able to quantify the presence of contaminants in the diesel. The results showed that adulterants concentrations were adequately reproduced by the fluorescence spectral data.

Total spectrofluorimetry associated with Principal Component Analysis (PCA) was used to discriminate samples of vegetable oil and animal fat. In addition, a multivariate calibration model was developed that combines spectroflurimetry with Partial Least Squares (PLS) for prediction of concentration of animal fat in mixture with vegetable oil. The multivariate calibration model had an R² value of 0.98098, which indicates the accuracy of the model. This method has potential application in the control of quality of raw material for production of biodiesel. The control of the concentration of animal fat is important because animal fat is more susceptible to oxidation than vegetable oil. Furthermore, high concentrations of animal fats may increase electricity costs for biodiesel production due to the high melting points of saturated fats that solidify at room temperature and cause the fouling and clogging of pipes.

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: Erythroxylaceae is a family composed of four genera being Erythroxylum the only one represented in the Neotropical region. Chemical studies indicate the presence of alkaloids, terpenes, flavonoids and phenolic compounds as main compounds. The incorporation of cytotoxic activity assays of natural products using cell cultures assists in the selection of potential chemotherapeutic agents. In this work we describe a revision of the cytotoxicity evaluation studies performed with extracts and/or pure substances obtained from Erythroxylum species through an integrative review. We have found studies that evaluated the cytotoxic activity of 21 species of Erythroxylum against 45 different cell lines, the analysis of the chemical composition of these species shows that the metabolites present in each species influence the cytotoxic potential of them, especially the presence of disubstituted tropane alkaloids species with the highest cytotoxic potential. MTT and Sulforrodamine B assays were the main in vitro tests used for the evaluation of the cytotoxic activities. From the total of species, less than 10% of the Erythroxylum species have already been evaluated for the cytotoxic activity, four of them showed high cytotoxic activity according to with the criteria of the NCI plant screening program. Thus, this genus represents a potential source of natural products with antitumor activity.