Identification of flavonoids in Hymenaea martiana Hayne (Fabaceae) by HPLC-DAD-MSn analysis.

Hymenaea martiana is a native tree known in Brazil as 'jatobá' and used in folk medicine to treat pain and inflammation. The aim of this work was to identify the flavonoids present in the crude ethanolic extract and ethyl acetate fraction using HPLC-DAD and LC-MSn analysis. The ethanolic extract was partitioned to obtain the ethyl acetate fraction. The analysis of astilbin content also was carried out by HPLC analysis. HPLC-DAD-ESI/MSn analysis of the ethanolic extract and ethyl acetate fraction revealed the presence of eleven peaks in the chromatograms, and all these peaks were identified: taxifolin, eucryphin, astilbin and 3 diastereoisomers, engeletin and 2 diastereoisomers, quercitrin and 2,6,3',4'-tetrahydroxy-2-benzylcoumaran-3-one. The ethyl acetate fraction had a higher astilbin concentration (151.87 µg/mL) than the ethanolic extract (40.13 µg/mL). In conclusion, the species could be considered a good source of flavonoids, which can be related to the main chemotaxonomic markers for the genus Hymenaea.

The Fatty Acid Composition of Vegetable Oils and Their Potential Use in Wound Care.

OBJECTIVE: To evaluate the similarities among fatty acid compositions of vegetable oils sold in the Brazilian market and those present in a reference health product used to treat wounds. METHODS: The relative amounts of fatty acids in 21 types of vegetable oils, purchased in the Brazilian market, were assessed using gas chromatography-mass spectrometry and flame ionization detection. MAIN RESULTS: The studied oils had similar fatty acid compositions to the reference product (caprylic acid, 18.8%; capric acid, 17.4%; oleic acid, 27.5%; and linoleic acid, 28.1%). The presence of caprylic acid (10.45% ± 0.07%), capric acid (5.8% ± 0.75%), lauric acid (45.63% ± 0.93%), and myristic acid (16.33% ± 2.23%) were detected in all the vegetable oils tested. Oleic acid (52.94% ± 12.54%) was present in andiroba, avocado, canola, copaiba, olive, palm, pequi, and pracaxi oils and featured prominently in olive oil (75.8%). Linoleic acid (57.09% ± 8.47%) was present in corn, cottonseed, grapeseed, passion fruit, and sunflower oils and in mixed oils (olive with soybean and sunflower with corn and canola). CONCLUSIONS: Most of the vegetable oils tested are products of plants from tropical climates, where they are abundant and easy to cultivate. It is possible that a balanced composition of fatty acids obtained from natural sources could be an effective alternative treatment for wounds.

Dereplication of Flavonoid Glycoconjugates from Adenocalymma imperatoris-maximilianii by Untargeted Tandem Mass Spectrometry-Based Molecular Networking.

The interpretation of large datasets acquired using high performance liquid chromatography coupled with tandem mass spectrometry represents one of the major challenges in natural products research. Here we propose the use of molecular networking to rapid identify the known secondary metabolites from untargeted MS/MS analysis of Adenocalymma imperatoris-maximilianii plant extracts. The leaves, stems and roots of A. imperatoris-maximilianii were extracted using different solvents according to Snyder selectivity triangle. The samples were analyzed by HPLC coupled with ion trap mass spectrometer in a collision-induced dissociation MS/MS configuration in both positive and negative electrospray ionization modes. Molecular networking simultaneously organized the spectra by cosine similarity. The chemical identification was performed based on the systematic study of the main fragmentation pathways observed for the resulting network. The untargeted tandem mass spectrometry-based molecular networking allowed for the identification of 63 metabolites, mainly mono-, di- and tri-, C- and/or O-glycosyl flavones. Molecular networking was capable not only to dereplicate known flavonoids, but also to point out related prenyl derivatives, described for the first time in Adenocalymma species. The gas-phase reaction route to form the characteristic [M-H2O-(30/60/90)]+ fragments in C-glycosyl flavones was suggested as sequential sugar ring opening followed by retro-aldol elimination involving aldose-ketose isomerization. The use of molecular networking with LC-CID-MS/MS assisted the identification of various isomeric and isobaric flavonoid glycoconjugates by establishing clusters according to the fragmentation similarities. Additionally, the proposed cross-ring sugar cleavages can contribute to the identification of C-glycosides by MS/MS analysis.