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1.
Molecules ; 28(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375216

RESUMO

Virgin coconut oil (VCO) is a functional food with important health benefits. Its economic interest encourages fraudsters to deliberately adulterate VCO with cheap and low-quality vegetable oils for financial gain, causing health and safety problems for consumers. In this context, there is an urgent need for rapid, accurate, and precise analytical techniques to detect VCO adulteration. In this study, the use of Fourier transform infrared (FTIR) spectroscopy combined with multivariate curve resolution-alternating least squares (MCR-ALS) methodology was evaluated to verify the purity or adulteration of VCO with reference to low-cost commercial oils such as sunflower (SO), maize (MO) and peanut (PO) oils. A two-step analytical procedure was developed, where an initial control chart approach was designed to assess the purity of oil samples using the MCR-ALS score values calculated on a data set of pure and adulterated oils. The pre-treatment of the spectral data by derivatization with the Savitzky-Golay algorithm allowed to obtain the classification limits able to distinguish the pure samples with 100% of correct classifications in the external validation. In the next step, three calibration models were developed using MCR-ALS with correlation constraints for analysis of adulterated coconut oil samples in order to assess the blend composition. Different data pre-treatment strategies were tested to best extract the information contained in the sample fingerprints. The best results were achieved by derivative and standard normal variate procedures obtaining RMSEP and RE% values in the ranges of 1.79-2.66 and 6.48-8.35%, respectively. The models were optimized using a genetic algorithm (GA) to select the most important variables and the final models in the external validations gave satisfactory results in quantifying adulterants, with absolute errors and RMSEP of less than 4.6% and 1.470, respectively.


Assuntos
Contaminação de Alimentos , Óleos de Plantas , Óleo de Coco , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Fourier , Contaminação de Alimentos/análise , Óleos de Plantas/análise , Análise dos Mínimos Quadrados , Azeite de Oliva/análise
2.
PeerJ ; 10: e13683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35996664

RESUMO

Background: Pulse crops are considered the major sources of proteins, dietary fiber, micronutrients, and bioactive phytochemicals. Among the numerous pulse crops, broad beans (Vicia faba L.) have received particular attention due to their nutraceutical, functional and economic importance. Our attention was mainly focused on the broad bean pods (VFs), which are the primary by-product of the domestic and industrial processing of broad beans and an attractive source of valuable ingredients. Methods: In order to investigate the VFs properties, the flours from broad beans of three different harvest periods were extracted with acetone, methanol and 70% aqueous ethanol and the dried extracts were analyzed, qualitatively and quantitatively, and tested for their antioxidant through DPPH and ABTS assay and anticancer activities using the MTT assay and immunofluorescence analysis. Results: The VF extracts demonstrated a good in vitro radical scavenging activity from the first stage of collection of all the V. faba L. extracts. Additionally, the extracts were tested for their cytotoxicity against a panel of cancer and normal cells and the outcomes indicated the ethanol extract as the most active against the melanoma cell line Sk-Mel-28, without affecting the viability of the normal cells. Finally, we found out that the ethanol extract interfered with the microtubules organization, leading to the cancer cells death by apoptosis.


Assuntos
Antioxidantes , Vicia faba , Antioxidantes/farmacologia , Vicia faba/química , Extratos Vegetais/farmacologia , Fenóis/análise , Sementes/química , Suplementos Nutricionais/análise , Etanol/análise
3.
Rapid Commun Mass Spectrom ; 21(14): 2273-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17577877

RESUMO

Protonated 1,4-benzodiazepines dissociate in the gas phase by the common pathway of CO elimination and by unique pathways dictated by the substituents; the latter typically differentiate one benzodiazepine from another. Protonated 3-dihydro-5-phenyl-1,4-benzodiazepin-2-one, the base diazepam devoid of substituents, dissociates by eliminating CO, HNCO, benzene, and benzonitrile. Mechanisms of these reactions are proposed with ionic products being resonance stabilized. The abundant [MH-CO]+ ion dissociates to secondary products via elimination of benzene, benzonitrile, the NH2 radical, and ammonia, yielding again ionic products that are stabilized by resonance.


Assuntos
Benzodiazepinas/química , Gases/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Benzodiazepinas/análise , Avaliação Pré-Clínica de Medicamentos/métodos , Gases/análise , Transição de Fase , Prótons
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