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Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk

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Asian Pacific journal of Tropical Medicine 2018年第12期11卷 676-681页

作者： Adriana Méndez-Flores Ayerim Hérnandez-Almanza Aidé sáenz-Galindo jesús Morlett-Chávez Cristóbal N Aguilar juan ascacio-valdés Bioprocesses and Bioproducts Research Group Food Research Department School of Chemistry Autonomous University of Coahuila Organic Chemistry Department School of Chemistry Autonomous University of Coahuila Molecular Biology Laboratory School of Chemistry Autonomous University of Coahuila

Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/EsI/Ms. The antioxidant activity was carried out by ABTs, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/EsI/Ms analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTs, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.

关键词： Mexican variety rambutan Ultra-sound assisted extraction Antioxidant polyphenolic compounds HPLC/EsI/Ms

Polyphenolic content, in vitro antioxidant activity and chemical composition of extract from Nephelium lappaceum L.(Mexican rambutan) husk

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Asian Pacific journal of Tropical Medicine 2017年第12期10卷 1201-1205页

作者： Cristian Hernández juan ascacio-valdés Heliodoro De la Garza jorge Wong-Paz Cristóbal Noé Aguilar Guillermo Cristian Martínez- ávila Cecilia Castro-López Antonio Aguilera-Carbó Department of Animal Nutrition Universidad Autónoma Agraria Antonio NarroCol. BuenavistaCalzada Antonio Narro No. 1923Saltillo25315CoahuilaMexico Food Research Department School of ChemistryUniversidad Autónoma de CoahuilaBlvd. Venustiano CarranzaCol. RepúblicaSaltillo25280CoahuilaMexico Chemistry and Biochemistry Laboratory Faculty of AgronomyUniversidad Autónoma de Nuevo LeónFrancisco I. Madero S/NHacienda el Canada66050General EscobedoNLMexico

Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/EsI/Ms characterization of extract from Nephelium lappaceum L.(Mexican rambutan).Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI *** vitro antioxidant activity was performed using ABTs and ferric reducing antioxidant power ***: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTs and ferric reducing antioxidant power *** HPLC/EsI/Ms assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample;the mineral composition was also ***: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potential applications as bioactive antioxidant agents for the treatment of diseases.

关键词： Mexican rambutan Polyphenolic compounds Ellagitannins HPLC/EsI/Ms

Antifungal ellagitannin isolated from Euphorbia antisyphilitica Zucc

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Asian Pacific journal of Tropical Biomedicine 2013年第1期3卷 41-46页

作者： juan ascacio-valdés Edgardo Burboa Antonio F Aguilera-Carbo Mario Aparicio Ramón Pérez-schmidt Raúl Rodríguez Cristóbal N Aguilar Department of Food science and Technology Universidad Autónoma de Coahuila Department of Forest Engineering Universidad Autonoma Indigena de Mexico Department of Food science and Technology Universidad Autonoma Agraria "Antonio Narro" Agilent Technologies Inc.Varian's EduCare Training Program Instrumentation Analitica sA de CV Department of Food science and Technology Universidad Autonoma de Coahuila Department of Food science and Technology Universidad Autonóma de Coahuila

Objective:To study antifungal activity of a new ellagitannin isolated from the plant residues of Euphorbia antisyphilitica(***)Zucc in the wax extraction ***:An extract was prepared from dehydrated and pulverized residues and fractionated by liquid chromatography on Amberilte XAD-16,until obtained an ellagitannin-rich ethanolic fraction which was treated by rotaevaporation to recover the ellagitannin as fine *** aqueous solution was prepared and treated through ionic exchange liquid chromatography(Q XL)and gel permeation chromatography(G 25).The ellagitannin-rich fraction was thermogravimetrically evaluated(TGA and DTA)to test the thermo-stability of ellagic acid(monomeric unit).Then ellagitannin powder was analyzed by infrared spectrospcopy to determinate the functional groups *** mass spectroscopy was used to determine the molecular ***:The principal functional groups of ellagitannin were determined,the molecular weight was 860.7 g/mol;and an effective antifungal activity against phytopathogenic fungi was ***:It can be concluded that the new ellagitannin(860.7 g/mol)isolated from *** Zucc is an effective antifungal agent against Alternaria alternata,Fusarium oxyzporum,Colletotrichum gloeosporoides and Rhizoctnia solani.

关键词： Isolated Ellagitannin Euphorbia antisyphilitica Zucc Antifungal activity

Growth plasticity of conifers did not avoid declining resilience to soil and atmospheric droughts during the 20th century

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Forest Ecosystems 2023年第2期10卷 238-251页

作者： Tong Zheng jordi Martínez-Vilalta Raúl García-valdés Antonio Gazol j.julio Camarero Changcheng Mu Maurizio Mencuccini Northeast Forestry University Harbin150040China CREAF E08193 Bellaterra(Cerdanyola del Vallès)CataloniaSpain Universitat Autònoma de Barcelona E08193 Bellaterra(Cerdanyola del Vallès)CataloniaSpain Centre de Ciència i Tecnologia Forestal de Catalunya(CTFC) E-25280SolsonaSpain Department of Biology GeologyPhysics and Inorganic ChemistryRey Juan Carlos University28933MóstolesMadridSpain Instituto Pirenaico de Ecologia(IPE-CsIC) Zaragoza50059Spain ICREA 08010BarcelonaSpain

Background:Plasticity in response to environmental drivers can help trees cope with ***,our understanding of the importance of plasticity and physiological adjustments in trees under global change is ***:We used the International Tree-Ring Data Bank(ITRDB)to examine 20th century growth responses in conifer trees during(resistance)and following(resilience)years of severe soil and atmospheric droughts occurring in isolation or as compound *** resilience indices were calculated using observed growth divided by expected growth to avoid spurious correlations,in which the expected values were obtained by the autoregressive moving average(ARIMA)*** used high atmospheric vapour pressure deficit(VPD)to select years of atmospheric drought and low annual values of the standardized Precipitation-Evapotranspiration Index(sPEI)to select years with soil *** acquired the sensitivities(i.e.,the slopes of the relationships)by fitting the resilience indices as a function of environmental drivers,and assessed how these sensitivities changed over time for different types of drought events using linear mixed *** also checked whether plasticity in growth responses was sufficient to prevent long-term trends of growth reductions during or after severe *** acknowledge that by focusing on the response of surviving trees from the ITRDB we are potentially biasing our results towards higher resilience,as stand level responses(e.g.,mortality)may result in lowered competition after the disturbance ***:sensitivities of resilience to VPD and sPEI changed throughout the 20th century,with the directions of these changes often reversing in the second half of the *** the 1961–2010 period,changing sensitivities had positive effects on resilience,especially following years of high-VPD and compound events,avoiding growth losses that would have occurred if sensitivities had remained *** sensitivity changes,resilience

关键词： Tree rings Growth Drought Vapor pressure deficit Plasticity Acclimation

Changes in the Production of salicylic and jasmonic Acid in Potato Plants (<i>solanum tuberosum</i>) as Response to Foliar Application of Biotic and Abiotic Inductors

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American journal of Plant sciences 2015年第11期6卷 1785-1791页

作者： Esmeralda González-Gallegos Elan Laredo-Alcalá juan ascacio-valdés Diana jasso de Rodríguez Francisco Daniel Hernández-Castillo Departamento de Parasitología Agrícola Universidad Autónoma Agraria Antonio Narro Saltillo México

An alternative to the use of chemical fungicides is to enhance the defensive response of plants by appropriate stimulation, a phenomenon known as induction of resistance. The aim of this study was to determine the changes of endogen levels of salicylic acid (sA) and jasmonic acid (jA) in potato plants as response to foliar application of biotic and abiotic inductors. Treatments T1 = Best Ultra F (Bacillus spp. 108 cfu/mL and Pseudomonas fluorescens 108 cfu/mL) 0.5%, T2 = FullKover HF (microbial jasmonic acid 1500 ppm) 0.2%, T3 = T1 0.5% + T2 0.1%, T4 = Milor® (Chlorothalonil + Metalaxyl) 0.5% and T5 = control (water) were applied in potato plants. The application of biotic and abiotic inductors improved the sA and jA production in potato plants. The production of salicylic acid in potato plants was observed by application of Bacillus spp. and Pseudomonas fluorescens (T1) and fungicide Milor® (T4). The application of T1 Best Ultra F, T2 FullKover HF (microbial jA), T3 (T1 + T2) and T4 Milor® improved the jA production in potato plants.

关键词： salicylic Acid jasmonic Acid Bacillus spp. Pseudomonas fluorescens

Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in North Central Mexico

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journal of Arid Land 2014年第1期6卷 80-96页

作者： Carlos A AGUIRRE-sALADO Eduardo j TREVIO-GARZA Oscar A AGUIRRE-CALDERóN javier jIMNEZ-PREZ Marco A GONZLEZ-TAGLE josé R valdZ-LAZALDE Guillermo sNCHEZ-DíAZ Reija HAAPANEN Alejandro I AGUIRRE-sALADO Liliana MIRANDA-ARAGóN Faculty of Forest sciences Autonomous University of Nuevo Leon Faculty of Engineering Autonomous University of San Luis Potosi Forestry Program Postgraduate College Haapanen Forest Consulting Faculty of Agronomy and Veterinary Autonomous University of San Luis Potosí

As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest ***,national governments are interested in developing forest-monitoring strategies using geospatial *** statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical *** derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the *** of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out *** results indicate that the Most similar Neighbor(MsN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the *** findings confirm the predictive potential of the MsN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).

关键词： k-nearest neighbor Mahalanobis most similar neighbor MODIs BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation

Magnetocaloric effect in ErNi2 melt-spun ribbons

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journal of Rare Earths 2020年第6期38卷 612-616页

作者： j.L.sanchez Llamazares P.Ibarra-Gaytan C.F.sanchez-valdes D.Rlos-jara P.Alvarez-Alonso Instituto Potosino de Investigacion Ciendfica y Tecnoldgica A.C. Camino a la Presa San Jose 2055Col.Lomas 4San Luis Potosi.S.LP.78216Mexico CPM-TIP University Pavol Jozef SafarikPark Angelinum 9.04154 KosiceSlovakia Division Multidisciplinaria Ciudad UniversitariaUniversidad Aurdnoma de Ciudad Juarez(UACJ)Calle Jose de Jesus Macias Delgado#18100Ciudad Juarez 32579Chihuahua.Mexico Departamento de Fisica Universidad de OviedoCalvo Sotelo s/n33007 OviedoSpain

ErNi2 ribbons were produced by rapid solidification using the melt spinning *** structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning electron microscopy,magnetization and specific heat *** are single phase with the MgCu2-type crystal structure,a Curie temperature TC of 6.8 K and a saturation magnetization at2 K and 5 T of 124.0 A·m2/*** a magnetic field change μ0△H of 5 T(2 T) ribbons show a maximum magnetic entropy change |△sMpeak| of 24.1(16.9) j/(kg·K),and an adiabatic temperature change △Tadmax of8.1(4.4) K;this is similar to the previously reported literature for bulk alloys that were processed through conventional melting techniques followed by prolonged thermal *** addition,the samples also show slightly wider △sM(T) curves with respect to bulk alloys leading to a larger refrigerant capacity.

关键词： ErNi2 Laves phase Melt-spun ribbons Magnetic entropy change Adiabatic temperature change Rare Earths

Management of specific Complications after Congenital Heart surgery(I)

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Open journal of Pediatrics 2015年第1期5卷 56-66页

作者： A.sánchez Andrés C.González Mino E.valdés Diéguez L.Boni j.I.Carrasco Moreno Pediatric Cardiology Unit Hospital Universitario y Politécnico La FeValenciaSpain Pediatric Intensive Care Unit Hospital General de CastellónCastellonSpain Pediatric surgery Unit Hospital Universitario y Politécnico La FeValenciaSpain

In addition to the general consequences of surgery and cardiopulmonary by-pass, lesion-specific complications can occur after surgery for congenital heart disease. It is important for the pediatric intensive care specialist to fully understand the preoperative anatomy and the intraoperative details of these patients. This allows a timely and appropriate treatment of general and lesion-specific complications. In this article we provide a list of commonly-performed surgical procedures and possible associated problems to be anticipated in the early postoperative period. Then it follows a discussion about the diagnosis and management of these complications, based on their pathophysiological features.

关键词： Congenital Heart Diseases Pediatric Heart surgery Postoperative

specific Injuries Management in the Postoperative of Congenital Heart Diseases(Ⅱ):Univentricular Hearts

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Open journal of Pediatrics 2015年第1期5卷 67-75页

It is very important to understand that the univentricular heart surgery is just palliative, not being in anyway a definitive or curative surgery, but nowadays it’s the best initial treatment of this complex heart disease. The fundamental philosophy of treatment of every univentricular heart is to ensure the flow system and/or restrict the lung flow. Thus, initially a patient with univentricular heart who is undergoing surgery may need to ensure systemic flow (reconstruction of the aortic?arch type Norwood), to restrict the lung flow (pulmonary banding) or to provide enough?pulmonary flow (pulmonary-systemic fistulae). However, some heart diseases with univentricular physiology remain “balanced” autonomously, until the “second” stage of palliation is performed (cavo-pulmonary anastomosis type Glenn), but others require performance of pulmonary banding, if there’s no native lung protection and/or repair of the systemic circuit in a first stage, to reach next palliation steps in the best possible conditions.

关键词： Univentricular heart Postoperative Congenital heart disease Norwood Glenn Fontan