Browsing Química by Procedence
Now showing items 1-20 of 41
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A Metabolic Widget Adjusts the Phosphoenolpyruvate-Dependent Fructose Influx in Pseudomonas putida
(2016)Fructose uptake in the soil bacterium Pseudomonas putida occurs through a canonical phosphoenolpyruvate (PEP)-dependent sugar transport system (PTSFru). The logic of the genetic circuit that rules its functioning is puzzling: ... -
Aceptación de un jugo de mora endulzado con estevia en contraste con otros edulcorantes
(2017)El objetivo de la presente investigación fue desarrollar un jugo de mora (Rubus adenotrichus), endulzado con esteviolglucósidos (glucósidos obtenidos a partir de las hojas de Stevia rebaudina Bertoni) como una bebida ... -
Adipostatins E-J, new potent antimicrobials identified as inhibitors of coenzyme-A biosynthesis
(2020-01)Phosphopantetheine is a key structural element in biological acyl transfer reactions found embedded within coenzyme A (CoA). Phosphopantothenoylcysteine synthetase (PPCS) is responsible for installing a cysteamine group ... -
Aggregation Pheromone of Coconut Rhinoceros Beetle, Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae)
(1995-10)Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. ... -
ArsH protects Pseudomonas putida from oxidative damage caused by exposure to arsenic
(2020-03-23)The two As resistance arsRBC operons of Pseudomonas putida KT2440 are followed by a downstream gene called arsH that encodes an NADPH‐dependent flavin mononucleotide reductase. In this work, we show that the arsH1 and (to ... -
Bocaparvovirus, Erythroparvovirus and Tetraparvovirus in New World Primates from Central America
(2020)Parvoviruses in the genera Bocaparvovirus (HBoV), Erythroparvovirus (B19) and Tetraparvovirus (PARV4) are the only autonomous parvoviruses known to be associated with human and non‐human primates based on studies and ... -
Composition, Chemical Fingerprinting and Antimicrobial Assessment of Costa Rican Cultivated Guavas (Psidium friedrichsthalianum (O. Berg) Nied. and Psidium guajava L.) Essential Oils from Leaves and Fruits
(2016-07-28)The essential oil of two related tree species, P. friedrichsthalianum and P. guajava, where obtained. A total of six different oil samples were recovered including leaves in dry/rainy season and fruits of both plant species. ... -
Concomitant prediction of environmental fate and toxicity of chemical compounds
(2020)The environmental fate of many functional molecules that are produced on a large scale as precursors or as additives to specialty goods (plastics, fibers, construction materials, etc.), let alone those synthesized by the ... -
Crystal structure of (E)-2-(tert-butylamino)-4-(tertbutylimino)naphthalen-1(4H)-one
(2018)The title compound, C18H24N2O, is the first example of a naphthoquinone imine derivative isolated in the 4-imine/2-amine tautomeric form having bulky alkyl substituents at the N atoms. The molecular conformation is stabilized ... -
Crystal structure of 4-[(adamantan-1-yl)amino]naphthalene-1,2-dione
(2019)The title compound, C20H21NO2, an example of a stable 1,2-naphthoquinone, was determined by single-crystal X-ray diffraction analysis at 100 K. This structure illustrates steric buttressing of the adamantanyl group, forcing ... -
Efficient syntheses of streptocarpone and (±)-a-dunnione
(2007)An efficient divergent synthesis of both streptocarpone and racemic α-dunnione from lawsone are described. A one-pot, formal [3+2] cyclization to form a furanonaphthoquinone directly provided a common intermediate. -
Essential oil from leaves of Myrcianthes fragrans (Myrtaceae) from Costa Rica. A new chemotype?
(2017)Myrcianthes is a Myrtaceous genus of flowering plants of about 30 to 40 species, distributed in the American continent. The aim of this work was to study the chemical composition of the foliar essential oil from M. fragrans ... -
Essential oils of Baccharis trinervis (Asteraceae) from Costa Rica
(2017)Baccharis is an Asteraceae genus of flowering plants, which has about 340 to 400 species, ranging from the Southern United States to the Southern extreme of Argentina and Chile through Central America and the Caribbean ... -
Estrogenic and serotonergic butenolides from the leaves of Piper hispidum Swingle (Piperaceae)
(Journal of Ethnopharmacology 129(2): 220–226, 2010)Ethnopharmacological relevance: Our previous work has demonstrated that several plants in the Piperaceae family are commonly used by the Q’eqchi Maya of Livingston, Guatemala to treat amenorrhea, dysmenorrhea, and pain. ... -
Ethyl propionate: Synergistic kairomone for african palm weevil,Rhynchophorus phoenicis L. (Coleoptera: Curculionidae)
(1994-04)Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of ... -
General Chemistry Without Orbitals
(2020)We illustrate the solutions of Schroedinger's equation for the hydrogen atom in coordinates of all four systems, and differentiate the applicability of orbitals in these four systems. We present reasons that future textbooks ... -
Microbial Community Structure Alogn a Horizontal Oxygen Gradient in a Costa Rican Volcanic Influeced Acid Rock Drainage System
(2020-06-22)We describe the geochemistry and microbial diversity of a pristine environment that resembles an acid rock drainage (ARD) but it is actually the result of hydrothermal and volcanic influences. We designate this environment, ... -
Neutral organic redox pairs based on sterically hindered hydroquinone/benzoquinone derivatives for dye-sensitized solar cells
(2018-06)Substituted derivatives of hydroquinone/benzoquinone were studied as organic redox mediators in the electrolyte for dye-sensitized solar cells (DSSCs). Thus, di-tert-butylhydroquinone (DTHQ), thymohydroquinone (ThymHQ) and ... -
Optimization of semiochemical-based trapping of Metamasius hemipterus sericeus (Olivier) (Coleoptera: Curculionidae)
(1996-08)Response of adults of the West Indian sugarcane weevil,Metamasius hemipterus sericeus, to various semiochemical treatments and physical trap designs was studied in southern Florida in field-grown banana and Canary Island ... -
Oral administration of Costa Rican guava (Psidium friedrichsthalianum) juice induces changes in urinary excretion of energy-related compounds in Wistar rats determined by 1H NMR
(2020-08)Introduction: Psidium friedrichsthalianum fruits have in vitro antioxidant activity and their intake has been suggested to have potential health benefits; however, there is still no evidence on the potential in vivo effect ...