966 research outputs found
Optimization of a method for preparing solid complexes of essential clove oil with beta-cyclodextrins
Essential CO was successfully solubilized in aqueous solution by forming inclusion complexes with beta-cyclodextrins (beta-CDs). Moreover, phase solubility studies demonstrated that essential CO also forms insoluble complexes with beta-CDs. Based on these results, essential CO-beta-CD solid complexes were prepared by the novel approach of microwave irradiation (MWI) followed by three different drying methods: vacuum oven drying (VO), freeze drying (FD) or spray drying (SD). Quantification of the solid complexes formed pointed to the not involving heat, FD, as the best drying method, followed by VO and SD, which led to significantly lower amounts of encapsulated essential CO.Ciencias de la Alimentació
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Vitiligo-like lesions located over In-transit metastases of malignant melanoma as a clinical marker of complete response to pembrolizumab.
Anti-programmed cell death (PD)-1 therapies in metastatic tumors have a high incidence of immune adverse events, including cutaneous manifestations such as vitiligo-like lesions. This side effect is associated with increased survival and it is a clinical marker of response to treatment. This case report is a graphic representation of the appearance of vitiligo-like lesions over in-transit metastases of malignant melanoma linked to a complete response to treatment with pembrolizumab
Complexation of Eugenol (EG), as Main Component of Clove Oil and as Pure Compound, with β- and HP-β-CDs
Eugenol, both in its pure form (EG) and included in essential clove oil (CO) was successfully solubilized in aqueous solution by forming inclusion complexes with β-cyclodextrins (β-CDs) and its modified hydroxypropyl-β-CDs (HP-β-CDs). To investigate the molecular association between β-CDs/HP-β-CDs with pure EG and essential CO, phase solubility studies were undertaken. Essential CO formed insoluble complexes with β-CDs, but not with HP-β-CDs. The work clearly demonstrates complexes formation follow an order higher than 1:1 when high essential CO and β-CDs concentrations were used, however it was 1:1 in the case of essential CO-HP-β-CDs complexes. When pure EG was studied the results indicated that EG could form 1:1 inclusion complexes with β-CDs and HP-β-CDs. Based on the studies, the Kc values for pure EG were 4555 ± 225 M−1 and 10,633 ± 614 M−1 for β-CDs and HP-β-CDs, respectively, and 2005 ± 199 M−1 for essential CO-HP-β-CDs. These finding indicate that CDs are suitable for encapsulating EG.Ciencias de la Alimentació
Encapsulación de Aceites Esenciales de Clavo para su Aplicación en la Industria Alimentaria
Essential oils and extracts of various species of edible and medicinal plants, herbs, and spices constitute very potent biological active agents. They have a complex composition, containing from a few to several hundred constituents, mainly hydrocarbons and oxygenated compounds. Both, hydrocarbons and oxygenated compounds are responsible for odors and flavors, generated by aromatic plants as secondary metabolites (Ebrahimi et al., 2008).
Clove oil (CO) is an essential oil contained in the dried flower buds, leaves and stem of the tree Syzygiu aromaticum (Eastern Hemisphere) or Eugenia caryophyllata and Eugenia aromaticum (Western hemisphere) (Schmid, 1972). It has been used for centuries as an anesthetic for toothaches, headaches and joint pain (Shelef, 1983; Soto et al., 1995). Clove has received attention as an ideal fish anesthetic (Ackerman et al., 2002; Wagner et al., 2003; Hoskonen and Pirhonen, 2004; Roubach et al, 2005) and it has been used as a fragrant and flavoring agent in a variety of food and cosmetic products (Atsumi et al., 2001; Fujisawa et al., 2002., Ito et al., 2005).
Eugenol (EG) (4-allyl-2-methoxyphenol) is the principal constituent of the essential CO, accounting for 90-95% of the total oil amount (Briozzo et al., 1989; Gulcin et al., 2010). It has a strong phenolic smell and sharp acrid taste (Mouchreck, 2000; Ozturz et al., 2005). This phenolic compound has shown several biological activities such as anti-inflammatory activity, analgesic activity, anti-oxidative activity and anti-bacterial activity.
In the food industry, clove is often used in the form of ground, extracted essential oil or oleoresin, but always in a small amount due to its intense flavour. However, the use of CO could be a problem in industrial applications due to its high volatility and low stability. Hence, irritation the mucosa and skin, pungent taste, volatility, light sensitivity and poor water solubility make it unsuitable to use as such.
Considering the effectiveness and convenience of the application of essential CO and its main compound EG, the introduction of these compounds into food and cosmetic products has many challenges. These food ingredients are susceptible of degradation due to environmental stress conditions such as temperature, humidity, light, oxygen, interaction with other food ingredients and volatility of the aromatic compounds.
Encapsulation is the technique by which one material or a mixture of materials is coated with or entrapped within another material or system. The coated material is called active or core material, and the coating material is called shell, wall material, carrier or encapsulant. The development of microencapsulation products started in the 1950s with the research on pressure-sensitive coatings for the manufacture of carbonless copying paper (Green and Scheicher, 1955). Encapsulation technology is now well developed and accepted within the pharmaceutical, chemical, cosmetic, foods and printing industries (Augustin et al., 2001; Heinzen, 2002). In food products, fats and oils, aromatic compounds and oleoresins, vitamins, minerals, colorants and enzymes have been encapsulated (Dziezak, 1988; Jackson and Lee, 1991; Shahidi and Han, 1993).
The simplest form of microcapsules may consist of a core surrounded by a wall of uniform or non-uniform thickness. The core material may be composed of just one or several distinct types of ingredients whereas the carrier could be single or multilayered. The microcapsules are generally additives to a larger system and must be adapted to that system. Consequently, there are a number of performance requirements placed on microcapsules. A limited number of encapsulating methods exist (Versic, 1988) (Figure VI.1.1), but an enormous range of di¿erent materials can be used including proteins, carbohydrates (CDs, MDs, gums) and lipids (Brazel, 1999). The choice of wall materials depends upon a number of factors including: expected product objectives and requirements; nature of the core material; process of encapsulation; economics and whether the coating material is approved by the Food and Drug Administration (US) or European Food Safety Authority (Europe) (Amrita et al., 1991)
Being aware of the problems associated with the use of essential CO and its main compound EG, the aim of this study was using encapsulation as a tool in order to protect these sensitive bioactive compounds from degradation, eliminating unwanted effects and improving the effectiveness of their use in the industry.Ciencias de la Alimentació
Oxidative Stress and Antioxidant Defenses Induced by Physical Exercise
This chapter intends to present the physiological and biochemical mechanisms by which exercise induces the appearance of oxidative stress, as well as the characteristics of the physical exercise that involve the appearance of oxidative stress in the human organism
Choosing ICT engineering against the risc of exclusion in the future digital market
[ES] Este artículo analiza desde una perspectiva de género los factores económicos por los que las grandes multinacionales tecnológicas quieren atraer a las mujeres al mercado laboral TIC. El análisis de contexto presenta un sector masculinizado, con un 80% de titulados en ingeniería informática y en el que, de cada cien profesionales, setenta y ocho son hombres. El artículo ahonda en los factores sociales por lo que persiste la segregación ocupacional de género y las relaciones de género que alejan a las mujeres de la tecnología. Las múltiples formas de organizar el trabajo en este sector abren nuevas posibilidades para la conciliación laboral y familiar.[EN] This article analyses from a gender perspective the economic factors by which large technology multinationals want to attract women to the ICT labour market. The context analysis presents a masculinized sector with 80% of graduates in computer engineering and in which, out of every one hundred professionals, seventy-eight are men. The article delves into social factors so that occupational gender segregation persists and gender relations keep women away from technology. The multiple ways of organising work in this sector open up new possibilities for reconciling work and family life
Déficit vocacional en la era digital
Elegir el futuro profesional nunca ha sido tarea fácil para los jóvenes bachilleres. Si a esto le añadimos la inestabilidad del mercado laboral y el cambio de modelo productivo generado por el impacto de las TIC y la globalización, la decisión es mucho más compleja. Lo cierto es que, dentro de unos años, cuando los actuales jóvenes bachilleres inicien su trayectoria laboral en una sociedad tecnológicamente más avanzada, tendrán que elegir profesiones que aún no existen. En parte, esas nuevas profesiones se formarán de la convergencia de importantes áreas de especialización en ciencias y tecnología como la microinformática, la biotecnología y la física cuántica, además del resultado de la transformación digital que está operando transversalmente en otros muchos sectores de actividad como el de la educación, la salud, el transporte, la logística o el financiero. Este artículo forma parte del estudio empírico de mi tesis doctoral sobre el déficit de talento femenino en las ingenierías tecnológicas. En este texto trato de explicar la relación entre la digitalización de la economía, el empleo y la educación con la elección de estudios universitarios y el papel que están haciendo la Unión Europea, el Gobierno de España y otros organismos y asociaciones para motivar a las mujeres a estudiar ingenierías tecnológicas o trabajar en el sector TIC.Choosing the right career has never been an easy task for young high school graduates. If we add to this doubt the instability of the labour market, the productive model changed by the impact of the ITC and globalization, the final decision must be more complex. The truth is that, in a short time, when current students start working in a digital society, they will have to choose careers that do not exist yet. In part, the new careers will be formed by the convergence of three important specialization areas: microcomputation, biotechnology and quantum physics, as well as the result of the digital transformation that is being carried out transversally in many other sectors of activity such as education, health, transportation, logistics, business, etc. This article is an extract from an empirical study which I am developing in my doctoral thesis on the lack of female talent in the ICT engineering. In this text, I try to explain the relationship among the digitalization of the economy, the employment and education, and the selection of university studies and the role that the Spanish Government, the EU and other institutions and academic associations are playing in this area in order to encourage women to study ICT engineering or even to work in the ICT sector
Segunda lengua y su literatura (inglés): problemática y metodología
[Resumen] Programar de forma homogénea y con los mismos parámetros las dis-tintas opciones de Segunda Lengua y su Literatura: Inglés en las Licenciaturas de Filología Hispánica y Filología Francesa es un tarea difícil de llevar a cabo. Ni la
fundamentación ni las bases son las mismas, aunque el Ministerio las haya unifi-
cado con idénticos descriptores. En este trabajo ponemos de manifiesto las difi-
cultades surgidas al intentar programar la asignatura y presentamos dos plantea-
mientos distintos para su programación. El primero corresponde a una metodolo-
gía integrada (la lengua se enseña a través de los textos literarios) para alumnos
con un conocimiento de lengua inglesa avanzado y el segundo, a una metodología
no integrada (la lengua y la literatura forman dos bloques claramente delimitados)
para alumnos con un nivel menor de conocimientos de lengua inglesa.[Abstract] To design a homogeneous syllabus for Segunda lengua su literatura:
Inglés, in French Philology and Spanish Philology is a complex task when we have
to share the same parameters as it is indicated in the official descriptors of the
Ministry of Education for all the Segunda lengua y su literatura subjects. The stu-
dents enrolled in these academic degrees show a different point of departure which
enhances the difficulties in designing a proper syllabus. The aim of this paper is to
present two different approaches to the methodology used to teach the same sub-
ject in these two philologies. The first one proposes an integrated methodology (the
language is taught through literary texts) and is intended for students with an
upper-intermediate/advanced knowledge of the English language. The second,
comprises a non-integrated methodology (language and literature are two comple-
tely separated fields of study), for students with a lower level of English
Aplicación de la Metabonómica a la caracterización metabólica de cultivares de olivo en un programa de mejora genética.
Metabonomics has been applied to stablish a procedure in order to obtain the metabolic fingerprint of olive cultivars in a breeding program. High-resolution magic angle spinning NMR spectroscopy has made feasible the analysis of small pieces of olive intact flesh
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