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Tomato waste as a bioresource for lycopene extraction using emerging technologies

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Food Bioscience 2022年第5期49卷 99-108页

作者： J.Y.M´endez-Carmona J.A.Ascacio-Valdes Olga B.Alvarez-Perez Ayerim Y.Hern´andez-Almanza Nathiely Ramírez-Guzman Leonardo Sepúlveda Miguel A.Aguilar-Gonz´alez Janeth M.Ventura-Sobrevilla Crist´obal N.Aguilar School of Chemistry Universidad Aut´onoma de CoahuilaSaltilloMexico School of Biological Sciences Universidad Aut´onoma de CoahuilaTorre´onMexico Center for Interdisciplinary Studies and Research Universidad Aut´onoma de CoahuilaSaltillo25280Mexico Center for Research and Advanced Studies of the National Polytechnic Institute Ramos ArizpeCoahuilaMexico School of Health Sciences Universidad Aut´onoma de CoahuilaPiedras NegrasMexico

Background:Tomato is the second most important vegetable around the *** processing of the fruit generates waste such as damaged tomatoes,pulp,skin,seeds,and tomato-derived products that contain valuable biomolecules with functional and technological *** fruit extracts,mainly from waste,possess bioactive molecules,such as lycopene,with important biological applications in some *** and approach:The objective of this review is to analyze,discuss and synthesize the technologies that have been used for the extraction and recovery of the main lycopene present in tomato *** revised methodologies expose valuable results in the number of carotenoids recovered through the application of solvents,microwave-assisted,ultrasound-assisted,enzymatic-assisted,extraction at high pressure,and supercritical ***,the challenges continue concerning the quality of extracted compounds,economic accessibility,industrial reproducibility,and environmental *** findings and conclusions:The tomato waste contains important bioactive molecules,which are of interest in the food,pharmacological,biotechnological,and cosmetic *** information revised in this contribution pretends to support new research lines concerning the formulation of novel tomato waste bio-based functional ***,it is necessary to further analyze the new extraction and recovery conditions to keep the functional properties of this by-product.

关键词： Tomato waste Carotenoids Techniques for extraction Lycopene

New discriminant-function-based multidimensional discrimination of mid-ocean ridge and oceanic plateau

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Geoscience Frontiers 2020年第5期11卷 1681-1693页

作者： Surendra P.Verma Lorena Diaz-Gonzalez Instituto de Energias Renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco S/no.Col.CentroApartado Postal 34TemixcoMor62580Mexico Centro de Investigacion en Ciencias Universidad Autonoma de Estado de MorelosCuernavacaMorelos62209Mexico

From a compilation of geochemical data for the discrimination of the tectonic settings of mid-ocean ridge(MOR;3730 samples)and oceanic plateau(OP;3656 samples),we present two new discriminant functions and diagrams obtained from censored multivariate discordant outlier-free *** different sets of data(original concentrations as well as isometric log-ratio transformed(ilr)variables;all 10 major(M)elements as well as all 10 major and 6 trace elements MT)were used to evaluate the quality of discrimination from linear discriminant analysis(LDA)and canonical *** selected multidimensional models ilrM(9 ilr transformed variables of multi-normally distributed 10 major elements)and ilrMT(15 ilr transformed variables of multi-normally distributed combined 10 major and 6 trace elements),considered as the best or most representative(total of5650 samples for ilrM and 2858 for ilrMT),provided percent success values,respectively,of 80.9%for the MOR and 81.1%for the OP(ilrM)and 88.5%for the MOR and 90.1%for the OP(ilrMT).Both processes(log-ratio transformation and multi-normality)rendered the percent success values similar for both groups(MOR and OP).The respective discriminant functions were successfully used for four tests from known tectonic settings and four application cases(two for ophiolites and two for Precambrian rocks),documenting thus the utility of the new discrimination procedure for the MOR and OP tectonic ***,we showed that our multidimensional procedure is robust against analytical errors or uncertainties,as well as post-emplacement compositional changes caused by element mobility from both low or high temperature *** robustness against the gain or loss of a single element at a time was also documented,from which the ilrMT model was evaluated as more robust than the ilrM model.A new online computer program MOROPdisc was written in Java Framework ZK,which is freely available for use at our web portal http://***

关键词： MORB Multivariate discordant outliers Log-ratio transformation Multidimensional discrimination Analytical uncertainties Post-emplacement changes

Effects of Hedera helix *** on the understory early regeneration in an oak temperate forest in mexico City

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Ecological Processes 2023年第1期12卷 438-449页

作者： Héctor Adrián Jiménez-Hernández Leticia Bonilla-Valencia Yuriana Martínez-Orea Mara Jessica Zamora-Almazan Francisco Javier Espinosa-García Silvia Castillo-Argüero Facultad de Ciencias Universidad Nacional Autónoma de MéxicoMexico CityMexico Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de MéxicoMichoacánMexico

Background Hedera helix *** an invasive weed species introduced in several regions of the world,so it is relevant to study its effects on the plant community and the changes occurring after its *** established invaded(with/without removal of ***)and non-invaded(with/without removal of the understory)plots to compare some community attributes in an oak forest in mexico City and monitored them every 2 months for 1 year,taking soil samples to compare some edaphic variables between the *** invasive species negatively affect natural regenera-tion,seedlings of native species would be less abundant in plots invaded by *** than in the non-invaded *** invasive species modify the soil microbiota through exudates and often allelochemicals,soil chemical variables would differ between invaded and non-invaded *** The abundance of native species was lower in the invaded plots,but the richness and diversity of species were not statistically *** composition of the two invaded plots was similar to each other and more alike to that of the non-invaded *** species composition of the invaded plots was associated with soil potassium and phosphorus concentrations,whereas that of the non-invaded plots was more associated with soil nitrogen *** Following the removal of ***,several native species were registered,leading to a similar species composition as in the non-invaded plots,suggesting that some vegetation recovery can be expected following *** removal in 1 year.

关键词： Ivy Invasive plant Mechanical control Diversity Species composition

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Hardness-Lattice Parameter Correlation for Aged Al-Zn-Mg Alloys

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Journal of Materials Science & Technology 2010年第12期26卷 1083-1088页

作者： P.Fernandez G.Gonzalez I.Alfonso I.A.Figueroa Instituto de Investigaciones en Materiales Universidad Nacional Aut'onoma de M'exicoCircuito ExteriorCd.UniversitariaDel.Coyoac'anM'exicoDF.04510Mexico

Two ternary Al-2.2Zn-0.95Mg and ***-2.1Mg （in wt pct） alloys, with Zn：Mg ratios close to 2.5 were produced by conventional ingot casting metallurgy. The ingots were solution heat treated at 500℃ for 0.5 h and aged at 180℃ for times between 0.5 and 80 h. The structural characterization was carried out by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, selected area electron diffraction （SAED） and Vickers mierohardness measurements （HV）. The study was focused on the investigation of the precipitates formation and the relationship between hardness and lattice parameter for α-Al. The results showed that there was an inverse correlation for all the experimental conditions, and the aged peaks coincided with lattice parameter minima. Significant precipitates formation only occurred for the alloy containing 5.5 wt pct Zn and 2.1 wt pct Mg, provoking an important strengthening and variations in the lattice parameter, however, this was not observed for the alloy containing 2.2 wt pct Zn and 0.95 wt pct Mg. A plausible explanation of the increment of hardness values could be the presence of a well distributed η phase （MgZn2）. At initial stages of the precipitation process, η′ was the most abundant precipitate while the phase τ- was observed at overaged conditions. These results showed that the aging response of the conventionally cast Al-Zn-Mg alloys could be obtained using the lattice parameter of the α-Al matrix, even for alloy systems with low precipitates formation.

关键词： Aluminum alloy X-ray diffraction Precipitation Lattice parameter Hardness

Phase equilibrium modelling of the amphibolite facies metamorphism in the Yelapa-Chimo Metamorphic Complex, mexico

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Geoscience Frontiers 2021年第1期12卷 293-312页

作者： Fabian Gutierrez-Aguilar Peter Schaaf Gabriela Solís-Pichardo Gerardo F.Arrieta-García Teodoro Hernandez-Trevino Carlos Linares-Lopez Posgrado en Ciencias de la Tierra Instituto de GeofísicaUniversidad Nacional Autonoma de MexicoAv.Universidad 3000Ciudad de Mexico04510Mexico Laboratorio Universitario de Geoquímica Isotopica(LUGIS) Instituto de GeofísicaUniversidad Nacional Autonoma de MexicoAv.Universidad 3000Ciudad de Mexico04510Mexico Laboratorio Universitario de Geoquímica Isotopica(LUGIS) Instituto de GeologíaUniversidad Nacional Autonoma de MexicoAv.Universidad 3000Ciudad de Mexico04510Mexico Instituto de Geofísica Universidad Nacional Autonoma de MexicoAv.Universidad 3000Ciudad de Mexico04510Mexico

The Yelapa-Chimo Metamorphic Complex forms part of the Jalisco Block in western mexico and exposes a wide range of Early Cretaceous metamorphic rocks;such as paragneiss,orthogneiss,amphibolites,and ***,the pressure-temperature(P-T)conditions of metamorphism and partial melting remain poorly studied in the *** elucidate metamorphic P-T conditions,phase equilibrium modelling was applied to two sillimanite-garnet paragneisses,one amphibole-orthogneiss,and one ***-garnet paragneisses exhibit a lepidoblastic texture with a biotite+sillimanite+kyanite+garnet+quartz+plagioclase+K-feldspar mineral ***-orthogneiss and amphibolite display a nematoblastic texture with an amphibole+(1)plagioclase+quartz+(1)titanite assemblage and an amphibole+(2)plagioclase+(2)titanite+ilmenite retrograde mineral *** calculated for the two sillimanite-garnet paragneiss samples show P-T peak conditions at~6-7.5 kbar and~725-740℃.The results for amphibole-orthogneiss and the amphibolite yield P-T peak conditions at~8.5-10 kbar and~690-710℃.The mode models imply that metasedimentary and metaigneous units can produce up to~20 vol%and~10 vol%of melt,*** within a closed system during isobaric heating suggests that melt compositions of metasedimentary and metaigneous units are likely to have direct implications for the petrogenesis of the Puerto Vallarta *** new data indicate that the Yelapa-Chimo Metamorphic Complex evolved through a metamorphic gradient between~23-33℃km^-1and the metamorphic rocks formed at depths between~22 km and~30 km with a burial rate of~2.0 km Ma^-***,the P-T data for both metasedimentary and metaigneous rocks provide new constraints on an accretionary framework,which is responsible for generating metamorphism and partial melting in the YelapaChimo Metamorphic Complex during the Early Cretaceous.

关键词： Phase equilibrium modelling Yelapa-Chimo Metamorphic Complex Amphibolite facies Partial melting

Capturing Near-Equilibrium Solutions: A Comparison between High-Order Discontinuous Galerkin Methods and Well-Balanced Schemes

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Communications in Computational Physics 2019年第6期26卷 1-34页

作者： Maria Han Veiga David A.Velasco-Romero Remi Abgrall Romain Teyssier Institute of Computational Science University of ZurichSwitzerland Institute of Mathematics University of ZurichSwitzerland universidad autonoma del Estado de Morelos Mexico Instituto de Ciencias Fisicas Universidad Nacional Aut́onoma de ḾexicoMexico

Equilibrium or stationary solutions usually proceed through the exact balance between hyperbolic transport terms and source terms. Such equilibrium solutions are affected by truncation errors that prevent any classical numerical scheme from capturing the evolution of small amplitude waves of physical significance. In order to overcome this problem, we compare two commonly adopted strategies: going to very high order and reduce drastically the truncation errors on the equilibrium solution, or design a specific scheme that preserves by construction the equilibrium exactly, the so-called well-balanced approach. We present a modern numerical implementation of these two strategies and compare them in details, using hydrostatic but also dynamical equilibrium solutions of several simple test cases. Finally, we apply our methodology to the simulation of a protoplanetary disc in centrifugal equilibrium around its star and model its interaction with an embedded planet, illustrating in a realistic application the strength of both methods.

关键词： Numerical methods benchmark well-balanced methods discontinuous Galerkin methods

Microtextures on quartz grains from the Gulf of mexico and the Mexican Pacific coastal sediments:Implications for sedimentary processes and depositional environment

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Journal of Palaeogeography 2022年第2期11卷 256-274页

作者： Jayagopal Madhavaraju John SArmstrong-Altrin Kandasamy Selvaraj Rathinam Arthur James Estaci on Regional del Noroeste Instituto de GeologíaUniversidad Nacional Aut onoma de MexicoHermosilloSonora 83000Mexico universidad nacional aut onoma de mexico Instituto de Ciencias Del Mary LimnologíaUnidad de Procesos Oce anicosy CosterosCiudad UniversitariaCiudad de Mexico 04510Mexico department of Geological Oceanography and State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen UniversityXiamenChina department of Marine Science Bharathidasan UniversityTiruchirapalli620024Tamil NaduIndia

Microtexture analyes on quartz from coastal sediments of the Gulf of mexico and the Mexican Pacific Coast reveal 35 and 30 types of microtextures,respectively,which were grouped into mechanical,mechanical/chemical and chemical categories based on their mode of *** of chemical origin are rarer in the El Carrizal than in the Manzanillo beach sediments of the Mexican Pacific *** of mechanical origin like straight and curved scratches,pits,broken edges,and V-shaped marks indicate high energy,fluvial to marine depositional *** scarcity to absence of chemical features suggest that the energy level was higher at the Mexican Pacific coast than on the Gulf of mexico coast.V-shaped marks are common in the Gulf of mexico sediments,whereas they are abundant in the quartz grains from the Mexican Pacific *** frequency and density of V-shaped marks are produced by exceedingly high wave velocity during storm events or *** of V-shaped marks with fresh surfaces of quartz grains from the Mexican Pacific coast indicate an extremely high-energy impact *** quartz grains from the El Carrizal beach of the Mexican Pacific coast have abundant closely spaced Vshaped marks with fewer fresh *** high frequency of V-shaped marks is mainly linked to grain-tograin collision,typically associated with high-energy sub-aqueous conditions with a large volume of sedimentary particles in the water column that are produced during a tsunami or storm *** contrast,many quartz grains from the Gulf of mexico have large fresh surfaces with moderate percentages of V-shaped marks that might have been produced by high-energy waves with low sediment concentrations during storm events.

关键词： Microtextures Quartz grains V-shaped marks Tsunami and storm events Sedimentary processes

Airborne bacteria associated with particulate matter from a highly urbanised metropolis:A potential risk to the population’s health

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Frontiers of Environmental Science & Engineering 2022年第9期16卷 99-114页

作者： María del Carmen Calderón-Ezquerro Elizabeth Selene Gómez-Acata Carolina Brunner-Mendoza Instituto de Ciencias de la Atmósfera y Cambio Climático Universidad Nacional Autónoma de MéxicoCiudad de México 04510Mexico Facultad de Medicina Universidad Nacional Autónoma de MéxicoCiudad de México 04510Mexico

Bacteria in the air present patterns in space and time produced by different sources and environmental *** studies have focused on the link between airborne pathogenic bacteria in densely populated cities,and the risk to the population’s *** associated with particulate matter(PM)were monitored from the air of mexico City(mexico).We employed a metagenomic approach to characterise bacteria using the 16S rRNA *** bacteria sampling was carried out in the north,centre,and south of mexico City,with different urbanisation rates,during *** added to the particles were sampled using high-volume PM_(10) *** ascertain significant differences in bacterial diversity between zones and seasons,the Kruskal-Wallis,Wilcoxon tests were done on alpha diversity ***-three air samples were collected,and DNA was sequenced using next-generation *** results indicated that the bacterial phyla in the north and south of the city were Firmicutes,Cyanobacteria,Proteobacteria,and Actinobacteria,while in the central zone there were more *** were no differences in the alpha diversity indices between the sampled *** to the OTUs,the richness of bacteria was higher in the central *** diversity was higher in the rainy season than in the dry season;the Shannon index and the OTUs observed were higher in the central zone in the dry *** bacteria such as Kocuria,Paracoccus,and Micrococcus predominated in both seasonal times,while Staphylococcus,Corynebacterium,and Nocardioides were found during the rainy season,with a presence in the central zone.

关键词： Airborne bacteria Urbanisation PM10 mexico City Microbiome

Assessing conservation practices in Amalacaxco Gorge (Izta-Popo National Park, Central mexico) using fallout 137Cs and Optically Stimulated Luminescence (OSL)

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Journal of Mountain Science 2018年第3期15卷 447-460页

作者： MUNOZ-SALINAS E CASTILLO M departamento de Geología Regional Universidad Nacional Autónoma de México Ciudad UniversitariaCiudad de MexicoMexico Laboratorio nacional de Geoquimicay Mineralogia Ciudad Universitaria Ciudad de Mexico Mexico

This study aims to assess conservation practices in Izta-Popo National Park(Central mexico) by evaluating the mechanisms of sediment transfer. We applied a methodology based on fallout ^(137)Cs and optically stimulated luminescence(OSL) analysis. This was tested in the upper catchment of Amalacaxco Gorge, selected for being one of the sectors of the park in which man-made actions have been implemented in last decades to favor forest growth in the alpine grassland and to reduce the effect of water runoff. We quantified the ^(137)Cs activity using gamma and beta spectrometry of fine sediment grains extracted from the surface of parcels of 0.4 m2 in areas of natural forest, natural alpine grassland, alpine grassland with conservation practices, ravines and trails. In general, ^(137)Cs values increases as local slope decreases as it was expected. The natural forest is the most stable area in terms of soil erosion and sediment accumulation and, mean ^(137)Cs activity was taken as reference to assess cumulative zones, with higher ^(137)Cs values and erosive, with lower. We found that trails are accumulative surfaces but in other areas, erosion predominates. Man-made ditches, trenches and afforestation in the alpine grassland have higher ^(137)Cs values than thenatural grassland, which indicates that conservation practices are limiting the sediment transfer from hillslopes to channels, however, soil retention is less than in the natural grassland. Additionally, we evaluated the luminescence(OSL) values obtained from samples extracted from the sediment transported in ravines that are cutting into different sectors of the study area to assess the grade of resetting of fluvial materials. These luminescence results indicated that the sediment transported in ravines that are cutting into the natural forest and alpine grassland is bleached more efficiently than the sediment transported in the alpine grassland with conservation practices. Results of fallout ^(137)Cs and luminesce

关键词： Sediment transfer Soil erosion Natural protected areas Alpine grassland Caesium-137 Optically stimulated luminescence