Navegando por Palavras-chave "GC-MS"

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    Antispasmodic activity from Serjania caracasana fractions and their safety
    (Soc Brasileira Farmacognosia, 2017) Silva, Fabiana L.; da Silva, Joelmir L. V.; Silva, Jucileia M.; Marcolin, Luiza S. A.; Nouailhetas, Viviane L. A. [UNIFESP]; Yoshida, Massayoshi; Vendramini, Pedro H.; Eberlin, Marcos N.; Barbosa-Filho, Jose M.; Moreno, Paulo R. H.
    In a previous study, we reported the antispasmodic and gastroprotective effects of the Serjania caracasana (Jacq.) Willd., Sapindaceae, extract. In the present study, we evaluated the LD50, hemolytic and antispasmodic activities of its fractions and characterized its major constituents by isolation and GC-MS. The animals showed non-toxic symptoms with oral doses up to 2000 mg/kg, suggesting a safe oral administration. Furthermore, a low hemolytic activity was detected for the saponin fraction. Antispasmodic activity of the fractions was evaluated through carbachol-induced contractions in rat ileum. The hexane fraction was the most potent (IC50 68.4 +/- 5.9 mu g/ml) followed by the dichloromethane fraction (IC50 161.3.4 +/- 40.7 mu g/ml). Butanol fraction was the less effective (IC50 219.8 +/- 60.3 mu g/ml). The phyto-chemical study of the S. caracasana fractions afforded the isolation of friedelin, beta-amyrin, allantoin and quercitrin. This is the first time that the presence of allantoin and quercitrin in the Serjania genus has been reported. Among the isolated compounds and those characterized by GC-MS, beta-amyrin and beta-sitosterol were present in the most active fractions, hexane and dichloromethane, and they may be related to its antispasmodic activity. In addition, spathulenol was only found in the hexane fraction and its presence might justify the highest antispasmodic activity observed for this fraction. (C) 2017 Sociedade Brasileira de Farmacognosia. Published by Elsevier Editora Ltda.
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    Determination of eight fatty acid ethyl esters in meconium samples by headspace solid-phase microextraction and gas chromatography-mass spectrometry
    (Wiley-Blackwell, 2010-07-01) Roehsig, Marli; Louzada de Paula, Daniela Mendes; Moura, Sidnei; Albuquerque Diniz, Edna Maria de [UNIFESP]; Yonamine, Mauricio; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
    A number of fatty acid ethyl esters (FAEEs) have recently been detected in meconium samples. Several of these FAEEs have been evaluated as possible biomarkers for in utero ethanol exposure. in the present study, a method was optimized and validated for the simultaneous determination of eight FAEEs (ethyl laurate, ethyl myristate, ethyl palmitate, ethyl palmitoleate, ethyl stearate, ethyl oleate, ethyl linoleate and ethyl arachidonate) in meconium samples. FAEEs were extracted by headspace solid-phase microextraction. Analyte detection and quantification were carried out using GC-MS operated in chemical ionization mode. the corresponding D5-ethyl esters were synthesized and used as internal standards. the LOQ and LOD for each analyte were <150 and <100 ng/g, respectively. the method showed good linearity (r(2)>0.98) in the concentration range studied (LOQ -2000 ng/g). the intra- and interday imprecision, given by the RSD of the method, was lower than 15% for all FAEEs studied. the validated method was applied to 63 authentic specimens. FAEEs could be detected in alcohol-exposed newborns ( >600 ng/g cumulative concentration). Interestingly, FAEEs could also be detected in some non-exposed newborns, although the concentrations were much lower than those measured in exposed cases.
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    Estudo da biodegradação de hidrocarbonetos por bactérias provindas de mar profundo
    (Universidade Federal de São Paulo, 2017-08-10) Souza, Cindi Espada de [UNIFESP]; Vasconcellos, Suzan Pantaroto de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Oil seeps are locations with gas and oil infiltration occurring above ground or offshore structures (deep sea). Offshore exploration of these environments has been limited, due to their in situ sampling and observation difficulties. The advent of submarines and remotely operated vehicles (ROVs), recently, allowed the investigation of biological communities related to different physiological processes in oil seeps. In this context, the present work had the privilege to obtain samples for this environment, from developed expeditions at the Atlantic ocean region, known as São Paulo Plateau. It was possible to have 162 isolates of bacteria, those were submitted to fast screenings to verify abilities to survive using hexadecane as sole carbon source. It was also possible to select strains able to produce metabolites with emulsifying activity under automotive motor oil. The hydrocarbon biodegradation ability was evaluated by chromatographic analysis (GC-MS). In this context, three (3) isolates (Csh 01, Csh 26 and Csh 28A) were selected, showing hydrocarbon biodegradation indexes above to 50 %. Phylogenetically, these bacteria were affiliated to the genus Bacillus sp., closely related to Bacillus cereus species. Two (2) isolates (Csh 31 and Csh 32B) were selected about their emulsifying abilities, above to 50 %. The isolated Csh31 was characterized as Klebsiella oxytoca, while Csh 32B was identified as Bacillus pumilus.
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    Orange juice affects acylcarnitine metabolism in healthy volunteers as revealed by a mass-spectrometry based metabolomics approach
    (Elsevier Science Bv, 2018) Moreira, Vanessa [UNIFESP]; Brasili, Elisa; Fiamoncini, Jarlei; Marini, Federico; Miccheli, Alfredo; Daniel, Hannelore; Lee, Jennifer Ji Hye; Hassimotto, Neuza Mariko Aymoto; Lajolo, Franco Maria
    Citrus juices, especially orange juice, constitute rich sources of bioactive compounds with a wide range of health-promoting activities. Data from epidemiological and in vitro studies suggest that orange juice (OJ) may have a positive impact on lipid metabolism. However, the effect of orange juice intake on blood lipid profile is still poorly understood. We have used two different blood samples, Dried Blood Spots (DBS) and plasma, to assess the effect of two-week orange juice consumption in healthy volunteers by a mass-spectrometry based metabolomics approach. DBS were analysed by liquid chromatography mass spectrometry (LC-MS) and plasma samples were analysed by the gas chromatography mass spectrometry (GC-MS). One hundred sixty-nine lipids including acylcarnitines (AC), lysophosphatidylcholines (LysoPC), (diacyl- and acyl-alkyl-) phosphatidylcholines (PC as and PC ae) and sphingomyelins (SM) were identified and quantified in DBS. Eighteen fatty acids were identified and quantified in plasma. Multivariate analysis allowed to identify an increase in C3:1, C5-DC(C6-OH), C5-M-DC, C5:1-DC, C8, C12-DC, lysoPC18:3, myristic acid, pentadecanoic acid, palmitoleic and palmitic acid and a decrease in nervonic acid, CO, C2, C10, C10:1, C16:1, C16-OH, C16:1-OH, C18-OH, PC as C40:4, PC ae C38:4, PC ae C42:3, PC ae C42:4 and cholesterol levels after orange juice intake. A two-week period of orange juice intake could affect fatty acids beta-oxidation through mitochondrial and peroxisomal pathways, leading to an increase of short-chain acylcarnitines and a decrease of medium and long-chain acylcarnitines. This is the first report analyzing the effect of orange juice intake in healthy volunteers using a dried blood spot-based metabolomics approach.
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    Perfil químico dos óleos voláteis de indivíduos jovens de Nectandra megapotamica (Spreng.) Mez (Lauraceae) sob déficit hídrico 2018
    (Universidade Federal de São Paulo, 2018-11-23) Santos, Valdilene Maria dos [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    In this work the chemical composition of the volatile oils of the leaves of young individuals of Nectandra megapotamica under normal conditions of cultivation and under water deficit was carried out under three conditions: plants irrigated every two days (group I), every seven (group II) and every 15 days (group III). The study was conducted during 60 days in greenhouse, with biweekly collections, being repeated in three distinct periods, covering the four seasons of 2017 (summer/autumm, autumn/winter and spring). The qualitative and quantitative analysis of the constituents present in the volatile oils was performed using gas chromatography with flame ionization detector (GC/FID) and gas chromatography coupled to mass spectrometry (GC/ MS). 25 Compounds were identified, four monoterpenes (Δ 3 -carene, o-cymene, d-limonene and bornila acetate), eighteen sesquiterpenes (δ-elemene, α-copaene, βelemene, Z-α-bergamotene, β-caryophyllene, α-humulene, alloaromadendrene , germacrene D, δ-selinene, β-bisabolene, α-bisabolene, α-elemol, E-nerolidol, espatulenol, globulol, rosifoliol, alismol and α-bisabolol), as well as two diterpenes (caurene and E-phytol) and one phenylpropanoid (E-asarone). The summer/autumm and fall-winter experiments responded more strongly to the water deficits imposed, especially autumn-winter, in which the lowest water potential (-1.0 MPa) was observed. The contents of the constituents of the volatile oils of N. megapotamica underwent quantitative/qualitative variation throughout the experiment, being the most intense observed for the summer/autumm and fall-winter. The reductions in the relative proportions of the constituents were more evident for the oxygenated sesquiterpenes, especially for the plants with greater water restriction (group III). In addition, a systematic study was carried out throughout the year 2017, covering the summer/fall, autumn/winter and spring seasons, where relative variations of the constituents present in N. megapotamica volatile oils were observed. water deficiency treatments imposed. In order to understand which constituents had similarities and / or differences among them as a result of the treatments, principal component analyzes (PCA) were performed. It was possible to establish some relationships such as, in the summer/autumm experiment the α-bisabolol oxygen sesquiterpene was related to samples with higher water availability, whereas germacrene D was more relevant in samples with low water availability. Physiological analyzes (water potential, relative water content and growth rate) were also carried out to verify if the plants were responding to the treatments. In view of the obtained results, it can be suggested that the controlled conditions can be an alternative to select substances with biological activity of interest and commercially aggregated value, thus allowing the choice of Keywords: PCA, GC-FID, GC-MS, Water deficit, N. megapotamica, volatile oils, chemical composition. a better period to obtain them.