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Spirocyclic lactams and curvulinic acid derivatives from the endophytic fungus Curvularia lunata and their antibacterial and antifungal activities
(Fitoterapia, 2020-03-01) [Artigo]
Curvularia lunata, isolated from the capitula of Paepalanthus chiquitensis (Eriocaulaceae), was cultured in potato dextrose broth (PDB) medium. The ethyl acetate extract yielded two new spirocyclic γ-lactams (3 and 4), and ...
1H NMR spectroscopy combined with multivariate data analysis for differentiation of Brazilian lager beer according to brewery
(European Food Research and Technology, 2019-01-01) [Artigo]
In this study, 1H NMR spectroscopy was used to classify samples of beer, considering three categories (Ambev, Heineken, and Grupo Petrópolis), employing chemometric methods: principal component analysis (PCA), partial least ...
Antiprotozoal Sesquiterpene Pyridine Alkaloids from Maytenus ilicifolia
(Journal of Natural Products, 2012-05-01) [Artigo]
As part of a bioprospecting program aimed at the discovery of antiprotozoal agents from the Brazilian flora, two new sesquiterpene pyridine alkaloids, ilicifoliunines A (1) and B (2), along with the known alkaloids ...
Authentication of roasted and ground coffee samples containing multiple adulterants using NMR and a chemometric approach
(Food Control, 2020-06-01) [Artigo]
Brazil is still the world's largest producer and exporter of coffee. In order to maximize profits, some producers may add lower cost materials (such as corn, barley, or even coffee husks) to commercial coffee. In view of ...
Rapid determination of furosemide by combined spot test/diffuse reflectance spectroscopy to detect doping in sport
(Microchemical Journal, 2013-07-01) [Artigo]
This paper describes the development and application of a simple, cheap, and clean method for the quantification of furosemide in urine samples from athletes, to detect doping, using a combined spot test/diffuse reflectance ...
Development of a sensitive potentiometric sensor for determination of fumaric acid in powdered food products
(Food Chemistry, 2012-09-01) [Artigo]
A new potentiometric sensor, namely, Pt vertical bar Hg vertical bar Hg-2 FUM vertical bar graphite, where FUM represents the fumarate ion was developed for the measurement of fumaric acid in foods. The characteristics, ...
Development of a potentiometric sensor for the determination of saccharin in instant tea powders, diet soft drinks and strawberry dietetic jam
(Microchemical Journal, 2008-12-01) [Artigo]
The construction and the analytical evaluation of a potentiometric sensor, namely, Pt vertical bar Hg vertical bar Hg-2(Sac)2 vertical bar Graphite, where Sac stands for saccharinate ion, are described. This electrode has ...
Antibacterial activity of prenylated benzopyrans from Peperomia obtusifolia (Piperaceae)
(Natural Product Research, 2019-01-01) [Artigo]
Peperomia obtusifolia is a herbaceous perennial plant native to the Americas reported as a traditional medicine to treat snake bites and as a skin cleanser. The bioassay-guided fractionation of crude extracts from aerial ...
Antioxidant flavan-3-ols and flavonol glycosides from Maytenus aquifolium
(Phytotherapy Research, 2003-09-01) [Artigo]
TLC autographic assay revealed, in the EtOAc extract obtained from leaves and root bark of Maytenus aquifolium (Celastraceae), the presence of five compounds exhibiting antioxidant properties towards beta-carotene. They ...
Modulation of polyketide biosynthetic pathway of the endophytic fungus, Anteaglonium sp. FL0768, by copper (II) and anacardic acid
(Phytochemistry Letters, 2018-12-01) [Artigo]
In an attempt to explore the biosynthetic potential of endosymbiotic fungi, the secondary metabolite profiles of the endophytic fungus, Anteaglonium sp. FL0768, cultured under a variety of conditions were investigated. In ...