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1.
An Acad Bras Cienc ; 96(3): e20230970, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38985033

RESUMEN

The Irati Formation (Paraná Basin) is a mixed carbonate and organic-rich shale sequence intruded by Jurassic-Cretaceous basic rocks, featuring Brazil's most important oil shale deposits with different maturity levels. For the first time, the distribution of oil shale biomarkers from an outcrop section (quarry) of the Irati Formation in the northernmost Paraná Basin was analyzed by GC-MS and GC-MS/MS to determine the thermal evolution, organic matter origin and the depositional paleoenvironment. The organic-rich shale at the northernmost border of the basin has high similarity with the central and southernmost areas, indicating a primary control able to induce cyclic sedimentation in a broad (106 km2) and restricted environment. PCA and HCA analysis of bulk and molecular parameters showed changes in the organic matter composition and paleoenvironmental conditions throughout the stratigraphic column. Nonetheless, there are significant differences compared to the central-eastern and southern areas of the basin. Contrasting with the southern region, the north, predominates biphytane, low and medium gammacerane index. Pr/n-C17, Ph/n-C18, HI and OI values suggest type II/III kerogen from marine organic matter with freshwater input. Among the steranes, those of stereochemistry ααα 20R predominate over ααα 20S, and the presence of ßTm indicates the shales are less thermally evolved.


Asunto(s)
Biomarcadores , Sedimentos Geológicos , Brasil , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Biomarcadores/análisis , Cromatografía de Gases y Espectrometría de Masas , Lípidos/análisis , Fósiles
2.
Rev. bras. farmacogn ; 22(6): 1259-1267, Nov.-Dec. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-659042

RESUMEN

The essential oil (EO) of aerial parts of Lantana camara L., Verbenaceae, from Simões, Piaui, Northeast of Brazil, were obtained by hydrodistillation and analyzed by GC-FID and GC-MS techniques. In total, 68 compounds were identified. The most representative compounds of the oil were mono and sesquiterpenes. The main compounds found in the oil of the leaves in different months were β-caryophyllene (10.5%, in June of 2009), sabinene (7.98%, in September of 2008), limonene (7.68%, in September of 2008), spathulenol (11.64%, in September of 2008). The oil from stems of L. camara was characterized by a largest amount of sesquiterpenoids, with spatulenol (15.9%) and caryophyllene oxide (17.1% in June of 2009), as main components. β-Gurjunene (32.7%, in September of 2008) was the most prominent compound in the stems oils, which was absent or at very low relative abundance in leaves. L. camara essential oils from leaves were cytotoxic to V79 mammalian cells and also to Artemia salina, showing 50% lethal concentration (LC50) values from 0.23 µg/mL. The in vitro data obtained in this study suggested that EO may also be effective treating yeast infection in patients infected with fluconazole and terbinafine resistant isolates, but its toxicity must be monitored carefully.

3.
Rev. bras. farmacogn ; 19(3): 710-714, jul.-set. 2009. ilus, tab
Artículo en Portugués | LILACS | ID: lil-537914

RESUMEN

Os óleos essenciais de Lantana camara L. e Lantana sp., Verbenaceae, foram obtidos por hidrodestilação e seus componentes analisados por CG/EM. Tal procedimento analítico revelou a predominância dos sesquiterpenos, biciclogermacreno (19,42 por cento), isocariofileno (16,70 por cento), valenceno (12,94 por cento) e germacreno D (12,34 por cento) no óleo de L. camara, enquanto o biciclogermacreno (13,93 por cento), germancreno D (27,54 e β-cariofileno (31,50 por cento), por cento) destacaram-se como majoritários no óleo de Lantana sp. Os dois óleos foram submetidos a avaliação de atividades antibacteriana e de toxicidade usando as larvas de Artemia salina. Os resultados mostraram considerável atividade antibacteriana do óleo de L. camara, principalmente para Proteus vulgaris (ATCC 13315) e Escherichia coli (ATCC 25922). O óleo de Lantana sp. mostrou-se mais significativo contra Sthaphylococcus aureus (ATCC 10390). As atividades de toxicidade CL50 revelaram resultados inferiores ao limite padrão de 1000 μg/mL.


The essential oils from Lantana camara L. and Lantana sp. Verbenaceae, were obtained by hydrodistillation and analyzed by GC/MS. This GC/MS analysis revealed the sesquiterpenoids bicyclogermacrene (19.42 percent), isocaryophyllene (16.70 percent), valencene (12.94 percent) and germacrene D (12.34 percent) as majoritaries in the essential oil of L. camara, and bicyclogermacrene (13.93 percent), germacrene D (27.54 and β-caryophyllene (31.50 percent) in the essential oil from Lantana sp. The two essential oils were evaluated to antibacterial activity and toxicity using Artemia salina. The results revealed considerable antibacterial activity for essential oil from L. camara, meanly for Proteus vulgaris (ATCC 13315) and Escherichia coli (ATCC 25922). The essential oil of Lantana sp. showed major activity for Sthaphylococcus aureus (ATCC 10390). The evaluation of toxicity CL50 revealed results with minor values to limit pattern of 1000 μg/mL.

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