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1.
Nat Prod Res ; 34(9): 1311-1314, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30618269

RESUMEN

Volatile oil composition of leaves and fruits of Terminalia arjuna (Roxb.) was reported for the first time. Oils were extracted by microwave assisted hydrodistillation where yield of both oils were found to be 0.20% and their GC-MS analyses led to the identification of 65 and 48 constituents, respectively. Major constituents of leaves were carvacrol (11.17%), thymol (6.52%), α-terpinyl acetate (5.92%) and anethole (5.13%) while that of fruits were (E)-isoeugenol (11.48%), furfural (8.25%), p-vinylguaiacol (6.8%) and p-ethylguaiacol (5.72%) that demonstrated a significant difference between composition of its aerial parts, however, 33 constituents were identical that showed similarity characteristics in quality of these oils. Both leaf and fruit oils were found active against pathogenic and drug-resistant microbes: E. coli, Methicillin-resistant S. aureus, P. aeruginosa, Total-drug-resistant P. aeruginosa and K. pneumoniae with MIC values of 0.32, 0.32, 0.64, 0.64, 2.56 mg/mL and 0.16, 0.16, 0.32, 0.64, 1.28 mg/mL, respectively.


Asunto(s)
Antibacterianos/farmacología , Aceites Volátiles/análisis , Terminalia/química , Antibacterianos/análisis , Cimenos/análisis , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Klebsiella pneumoniae/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Componentes Aéreos de las Plantas/química , Hojas de la Planta , Pseudomonas aeruginosa/efectos de los fármacos , Terpenos/análisis , Timol/análisis
2.
RSC Adv ; 8(41): 22952-22962, 2018 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35540134

RESUMEN

Gasoline-ethanol (gasohol) fuel blends have gained considerable attention in the petroleum and energy sectors as relatively cheaper and greener high-octane alternative fuels with gasoline-comparable efficiency in modern transportation vehicles. However, due to different combustion rates the relative concentration of ethanol in gasohol fuel blends may vary over time. Furthermore, there is a need to monitor ethanol concentration in fuel blends for quality control applications. This article reports a miniaturized electronic sensor based on an interdigital capacitor (IDC) as the transducer and a dual-imprinted titania-polyaniline composite film as the receptor. The device has an active surface area of 0.9 cm2 and is easy to fabricate. The receptor material is synthesized by imprinting ethanol in both titania sol (EITS, the matrix) and polyaniline nanoparticles (EIPani, the filler), and subsequently mixing them to obtain a dual-imprinted EITS-EIPani composite. The structural and morphological characteristics of the receptor layers are determined with Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM), respectively. The IDC devices are fabricated with pristine EITS and dual-imprinted EITS-EIPani composite to test their metrological sensor characteristics in standard ethanol solutions and real-time gasohol fuel blends. The instant shift in capacitance is measured upon exposure to different concentrations of ethanol. These devices show excellent sensitivity and selectivity patterns and demonstrate reliable sensor response toward ethanol in different gasohol fuel blends with 1-10 vol% ethanol. The results of this study reveal that these miniaturized ethanol sensors are potentially useful for rapid analysis of ethanol in gasohol and may be optimized for onboard fuel quality control applications.

3.
Life Sci ; 83(19-20): 633-7, 2008 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-18834893

RESUMEN

AIMS: In primates, changes in nutritional status affect the hypothalamic-pituitary-gonadal (HPG) axis by still poorly understood mechanisms. Recently, hypothalamic kisspeptin-GPR54 signaling has emerged as a significant regulator of this neuroendocrine axis. The present study was designed to examine whether suppression of the reproductive function by acute food-restriction in a non-human primate is mediated by decreased responsiveness of the HPG axis to endogenous kisspeptin drive. MAIN METHODS: Five intact adult male rhesus monkeys habituated to chair-restraint, received intravenous boli of human kisspeptin-10 (KP10, 50 microg), hCG (50 IU), and vehicle (1 ml) in both fed and 48-h fasting conditions. Plasma concentrations of glucose, cortisol and testosterone (T) were measured by using enzymatic and specific RIAs, respectively. KEY FINDINGS: The acute 48-h fasting decreased plasma glucose (P<0.01) and T (P<0.005) levels, and increased cortisol levels (P<0.05). KP10 administration caused a robust stimulation of T secretion in both fed and fasted monkeys. However, mean T concentration and T AUC after KP10 administration were significantly (P<0.01-0.005) reduced in fasted monkeys. Likewise, the time of the first significant increase in post-KP10 T levels was also significantly (P<0.01) delayed. T response to hCG stimulation was similar in fed and fasted monkeys. SIGNIFICANCE: The present results indicate that under fasting conditions the KP10 induced T response is delayed and suppressed. These data support the notion that fasting-induced suppression of the HPG axis in the adult male rhesus monkey may involve, at least in part, a reduction in the sensitivity of the GnRH neuronal network to endogenous kisspeptin stimulation.


Asunto(s)
Ayuno/fisiología , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/fisiología , Proteínas Supresoras de Tumor/farmacología , Animales , Área Bajo la Curva , Glucemia/metabolismo , Gonadotropina Coriónica/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Hidrocortisona/sangre , Ketamina/farmacología , Kisspeptinas , Macaca mulatta , Masculino , Radioinmunoensayo , Testosterona/sangre
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