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La nochebuena (Euphorbia pulcherrima Willd. ex Klotsch) crece de manera silvestre en los bosques tropicales mexicanos en forma arbustiva y con brácteas rojas llamativas y con menor frecuencia presenta brácteas blancas. El uso principal de la nochebuena nativa es el ornamental, poco se ha estudiado acerca de las propiedades nutrimentales o nutracéuticas de la planta. El objetivo del presente estudio fue determinar el perfil de flavonoides y ácidos fenólicos presentes en los extractos metanólico-acuosos en brácteas de cinco variedades de nochebuena de sol para conocer sus propiedades nutrimentales y promover su consumo. Se utilizaron brácteas secas (0.5 g por muestra). La extracción de los compuestos se hizo a partir de una solución de metanol/agua (80:20 v/v). Se llevó a cabo un perfil de ácidos fenólicos y flavonoides por cromatografía de líquidos de alta resolución (CLAR) acoplado a un detector de arreglo de diodos. Los ácidos gálico y siringico fueron los que presentaron las concentraciones más altas en las variedades analizadas. El flavonoide rutina se encontró en altas concentraciones en todas las variedades, sin embargo, en la variedad Juan Pablo no se logró detectar floridzina y floretina. Estos resultados sugieren que las brácteas de nochebuena pueden aportar antioxidantes importantes al consumirse.

Background: Fruit yield in vanilla cultivation depends on climatic and genetic factors and management practices; however, studies on the influence of the environment on management systems for vanilla production are still limited. Objective: To evaluate the yield of vanilla fruit in three different management systems in correlation with their climate parameters. Methodology: 16 fruit yield components were evaluated in at least 10 repetitions; in addition, temperature, relative humidity, photosynthetically active radiation, and accumulated precipitation were recorded during the production cycle. The analysis of variance, Tukey´s test (α=0.05), and canonical correlation between yield components and climate parameters were performed under a randomized complete block design. Results: Vanilla fruit yield was influenced by the management system. The intensive system in shade mesh with an inert tutor (Barriles) had the highest yield of three evaluated sites, however, its fruits had lower weight and size than the system in acahual (20 Soles) and shade mesh with a living tutor (Solteros de Juan Rosas). The acahual system had a middle yield and the largest and heaviest fruits. The cultivation in shade mesh with living tutors in Solteros had low yield, attributable to high relative humidity and low photosynthetically active radiation during the cultivation cycle due to excessive shading of living tutors that as a whole could cause low floral induction and environmental stress promoting the development of diseases and premature fruit drop. Nevertheless, the fruits harvested in Solteros had physical characteristics similar to those of acahual (20 Soles). The effect of climate parameters was mainly reflected in inflorescences and fruit density. Implications: The incorporation of more study sites and cultivation cycles are necessary to extend the research, however, the information provided may be useful for producers to modify some of their management practices. Conclusions: The yield and size of vanilla fruits is influenced by the management system, since the highest yield occurred in the intensive system of shade mesh with inert tutors. The presence of diseases is a factor that could influence low fruit yield. Relative humidity and photosynthetically active radiation are the climate parameters with the greatest influence on fruit yield, particularly on fruits and inflorescences density in vanilla cultivation.

There are few studies in Mexico aimed at evaluating the genetic variability of Sechium spp. Despite certain biological variants are reported with very high potential to develop antineoplastic supplements to treat public health conditions. Using the Amplified Fragment Length Polymorphism (AFLP) technique, the genetic variability of a sample of 95 accessions of three species of Sechium (S. edule, S. chinantlense, S. compositum) was evaluated, with leaf DNA from the Banco Nacional de Germoplasma de Sechium edule en Mexico. Four combinations of AFPL were applied (EcoRI + ACC/MseI + CAC, EcoRI + ACC/MseI + CAT, EcoRI + ACC/MseI + CGC, and EcoRI + ACC/MseI + CGG). DNA samples were classified into three groups based on the flavour of the fruit (sweet, neutral, bitter). An average of 47.91% polymorphism, 0.16 heterozygosity, 32.83 number of polymorphic bands, and a zero Wright fixation index (Fst) was obtained. The evidence showed that the domesticated accessions (sweet, neutral) were separated from the bitter-taste genotypes. A monophyletic tree was generated with the genetic distance matrix and the neighbour-joining methodology. Analyses showed S. edule as the root taxon, deriving S. compositum and S. chinantlense as subgroups, and suggesting that there is not enough differentiation to treat them as separate species. The evaluated sample showed that there is no apparent reproductive barrier for genetic cross breeding. Genotypes behaved as a complex with evolutive dynamism; that genetic complexity would allow the design of new variants.

Pitaya (Stenocereus pruinosus) fruits, particularly those of the red variant, contain betalains that can be used to pigment foods and provide tonalities in the range of red–purple to orange-yellow. If betalains are separated into betacyanins (Bc) and betaxanthins (Bx), the potential for using them can be improved. Betalains are usually mixed with sugars, which limit their use since sugars can alter sensorial properties, and with other bioactive compounds, such as polyphenols, which can be beneficial due to their antioxidant potential. The objective was to separate betalains and soluble phenols from pitaya fruits and conduct the partition of betalains into Bc and Bx by multistage aqueous two-phase systems (ATPS). Pulp of pitaya fruits (294.25 μg/g betalains, 146.63 μg/g soluble phenols, and 34.31 mg/g sugars) were processed at 25 °C with ATPS prepared with 6.57–34.05% sodium citrate (Na3Cit) and 4.21–60.54% 1-propanol. Soluble phenols and sugars remained mainly in the bottom phases of ATPS with concentrations of 69.33–190.90 μg/mL and 20.89–45.88 mg/mL, respectively. The extraction efficiency of betalains was higher than 90% and these were separated into Bc and Bx, where Bc concentrated in the bottom phase and Bx in the top phase. Fractions with Bx/Bc ratios of 10.25 and 0.46 were obtained through multistage processing of top and bottom phases, which allowed recoveries of 45.94% Bx and 53.93% Bc, although the latter was in mixture with low concentrations of soluble phenols and sugars. ATPS has the potential to separate betacyanins and betaxanthins from pitaya fruits. Kewwords: Aqueous two-phase systems, Betalain partitioning, Pitaya fruit polyphenols, Sugar elimination from pigment

The efficacy of plant growth regulators (PGRs) has been demonstrated in the flowering of economically significant orchid hybrids, but studies of their effects in wild species with commercial potential are scarce. The effect of three doses of gibberellic acid (GA3) and 6-benzyladenine (BA), individually or in combination, and a control without PGRs, were evaluated during three flowering periods in Laelia anceps subsp. anceps, in the temporal behavior of flowering, morpho-floral quality parameters and in potential residual effects and malformations. Significant effects were observed between the experimental periods and doses used, with a single application of PGRs in the first period reducing the days to visible flower induction (DVFI), days to anthesis (DAN) and days of flower life (DFL), mainly in the first period. There were no significant differences between doses for morpho-floral quality parameters within each period, but differences existed between experimental periods, where the life and size of the flower increased in the first period, and the number of flowers and flower stems increased significantly in the second period. The doses of 2.37 mg · L−1 BA + 100 mg · L−1 GA3 showed highest significant consistency in the reduction of DVFI, DAN and increase of DFL and flower stems in the study. There were no floral malformations, and a positive residual effect was observed in temporal variables in the second period. Most of the doses used encourage beneficial effects in the various aspects of flowering evaluated.

En la mosca blanca Trialeurodes vaporariorum, plaga de importancia económica en hortalizas, su manejo con insecticidas sintéticos ha generado resistencia con efectos adversos para el ambiente. En la búsqueda de alternativas de manejo, se planteó esta investigación con el objetivo de cuantificar la repelencia de adultos con extractos crudos (metanol, etanol, diclorometano y hexano), aceites esenciales (AE) y compuestos mayoritarios de clavo y pimienta. En un vaso con 10 mL de agua, se colocó una hoja de tomate tratada a concentraciones de 1,0 a 0,000001 % y se introdujeron 20 adultos de 2 d de edad. Luego, de las 3 a las 72 h, se cuantificaron los adultos posados y por diferencia se determinó la repelencia. Los extractos crudos, AE y compuestos mayoritarios de clavo y pimienta repelieron entre 32,5 y 90,2 % la población de adultos de las 3 a las 72 h. Los AE de clavo y pimienta presentan mejor efecto repelente que los extractos crudos y compuestos secundarios, ya que lograron repeler de 46,2 a 100 %; el AE de clavo a la concentración de 1,0 % logró 100 % de repelencia a las 48 y 72 h y el AE de pimienta alcanza 97,5 % a las 72 h. En la práctica, se debe utilizar extracto crudo etanólico de ambas plantas a la concentración de 0,000001 % ya que logran repeler entre 38,7 y 87,5 % de adultos, de las 3 a las 72 h, y su efecto repelente persiste; además, es más fácil de conseguir, más seguro para el operador, distribuidor y consumidor; y está considerado en las normas de agricultura orgánica como solvente para la extracción de compuestos secundarios.

Jaltomata procumbens is a semidomesticated plant species used as food, and the presence of several types of secondary metabolites are detected in one of its forms. Growth conditions, the electrical conductivity (EC) of the nutrient solution, and the pruning management may influence the secondary metabolite content. The objective was to evaluate the effects of EC and pruning on the metabolite content of 2 J. procumbens forms, in greenhouse and hydroponics. Treatments included 2 forms (erect and decumbent), 3 EC levels (1, 2, and 3 dS m−1), and 2 pruning levels (with and without pruning). The contents of phenolic acids, flavonoids, and terpenoids were evaluated. EC and pruning management differentially influenced the contents of each group of metabolites in both forms in a combined and individual manner, with EC exerting a stronger effect than pruning. A total of 7 phenolic acids, 4 flavonoids, and 5 terpenoids were detected: the erect form contained significant amounts of syringic acid, rutin, and carnosol at 33.44, 36.43, and 0.26 mg 100 g−1 of dry weight, respectively, whereas the decumbent form had high contents of gallic and rosmarinic acids and morin at 59.03, 28.31, and 61.54 mg 100 g−1 of dry weight, respectively. Considering the variability observed depending on the metabolite group of interest, the specific management of EC and pruning is required for each form.

Objective: To identify the main alkaloids present in the seeds, calyx, and corolla of E. americana and E. coralloides (Fabaceae) using HPLC-MS. Design/methodology/approach: The seeds, calyx, and corolla of both species were separated; the crude alkaloid extracts were prepared according to the method described by Games et al. (1974). The crude alkaloid extracts were analyzed using a high-performance liquid chromatograph interfaced to a quadrupole ion trap mass spectrometer. Results: The lactonic alkaloids -a-erythroidine and b-erythroidine were the main alkaloids found in E. americana, whereas the presence of erythrinine and 8-oxo erythraline is typical of E. coralloides. These compounds can be used to distinguish both species. Limitations on study/implications: The use of the HPLC-MS technique allowed the detection of a large numbers of alkaloidal structures in different parts of the plants; however, this technique is not available in any laboratory. Findings/conclusions: A large number of erythrinane-like alkaloids were found in seed, calyx, and corolla. The use of seeds and flowers in the preparation of diverse traditional dishes can cause soothing and sedating effects in consumers, as a result of the presence of lactonic alkaloids. The HPLC-MS method allowed the detection of alkaloidal structures in flowers and seeds that had not been identified in previous studies about this species.

Natural products are in great demand because certain secondary metabolites (SMs) are sources of antioxidants, flavorings, active substances, or anticancer agents with less aggressiveness and selectivity, among which triterpenes and flavonoids are of importance because they inhibit carcinogenesis. For Sechium spp. P. Br. (chayotes), there is scientific evidence of antiproliferative activity that has occurred when cancer cell lines have been treated with this fruit. In order to compare future therapeutic designs and identify new and ancestral characteristics, triterpenes and flavonoids were determined in contrasting Sechium genotypes. The obtained data were analyzed via a cladistics approach, with the aim of identifying the characteristics and state of phytochemicals and genetic variables. The concentrations of flavonoids and triterpenes were determined, and a more complex composition of secondary metabolites was found in the wild types as compared to their domesticated genotypes. Bitter fruits contained a higher number of SMs, followed by those with a neutral and sweet flavor. A cladogram showed the differentiation of the three groups based on the flavor of the fruits. The diversity of SMs decreases in evolutionary terms, in response to domestication and environmental adaptation. Therefore, genotypes can be feasibly selected based on fruit flavor for gross-breeding, and cytotoxicity can be reduced without losing possible therapeutic effects.

Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) is a polyphagous insect pest native to America. Due to its capacity for adaptation and migration, it is currently located in Africa, Asia, and Oceania, where it threatens agricultural crops. The ability of S. frugiperda to develop resistance to insecticides is one of the reasons for the continuous search for more effective, low-cost, and environmentally friendly control products. In the present work, the insecticidal activity of ethanolic and hexane extracts obtained from fresh and dehydrated leaves of Piper auritum Kunth (Piperales: Piperaceae), Piper umbellatum L. (Piperales: Piperaceae), and Cedrela odorata L. (Sapindales: Meliaceae) was studied against first instar larvae of S. frugiperda. The ethanolic extracts of the dehydrated leaves of C. odorata and P. auritum presented insecticidal activity as high (100% mortality at a concentration of 92 mg/cm2) as that obtained with the positive control, Melia azedarach L. (Sapindales: Meliaceae). The GC-MS analysis of the extracts revealed the presence of phytochemicals classified mainly into the groups of monoterpenes, sesquiterpenes, diterpenes, phenylpropanoids, alcohols, and fatty acids. P. auritum grows and propagates rapidly. In addition, due to its low toxicity in mammals and non-target insects, it is a plant with the potential to be used as a botanical insecticide. The exposure of S. frugiperda larvae to low concentrations of ethanolic extract of P. auritum allowed us to observe their biological activity in the development of this insect. The LC50 was 22.1 mg/cm2. At sublethal concentrations (LC21 and LC35) the low fertility of the emerging adults was noticeable.

A profile of endogenous hormones and sugars in leaves and pseudobulbs of

Several plant extracts exhibit anti-virulence properties due to the interruption of bacterial quorum sensing (QS). However, studies on their effects at the preclinical level are scarce. Here, we used a murine model of abscess/necrosis induced by Pseudomonas aeruginosa to evaluate the anti-pathogenic efficacy of 24 plant extracts at a sub-inhibitory concentration. We analyzed their ability to inhibit QS-regulated virulence factors such as swarming, pyocyanin production, and secretion of the ExoU toxin via the type III secretion system (T3SS). Five of the seven extracts with the best anti-pathogenic activity reduced ExoU secretion, and the extracts of Diphysa americana and Hibiscus sabdariffa were identified as the most active. Therefore, the abscess/necrosis model allows identification of plant extracts that have the capacity to reduce pathogenicity of P. aeruginosa. Furthermore, we evaluated the activity of the plant extracts on Chromobacterium violaceum. T3SS (ΔescU) and QS (ΔcviI) mutant strains were assessed in both the abscess/necrosis and sepsis models. Only the ΔescU strain had lower pathogenicity in the animal models, although no activity of plant extracts was observed. These results demonstrate differences between the anti-virulence activity recorded in vitro and pathogenicity in vivo and between the roles of QS and T3S systems as virulence determinants.

Natural products are in great demand because certain secondary metabolites (SMs) are sources of antioxidants, flavorings, active substances, or anticancer agents with less aggressiveness and selectivity, among which triterpenes and flavonoids are of importance because they inhibit carcinogenesis. For

Resumen Introducción. Jaltomata procumbens (Cav.) J. L. Gentry, de uso alimenticio, se considera una especie semi-domesticada (poblaciones que han tenido un proceso de selección artificial pero aún tienen la capacidad de sobrevivir y reproducirse sin la intervención del ser humano) y que cumple con los criterios para su futuro uso. Objetivo. Evaluar caracteres agronómicos de dos poblaciones de J. procumbens, en invernadero e hidroponía. Materiales y métodos. La investigación se realizó en el Colegio de postgraduados, Campus Montecillo, Texcoco, Estado de México, de julio a diciembre de 2019. Se aplicaron los siguientes tratamientos en un sistema hidropónico abierto: dos poblaciones (erguida y decumbente), tres niveles de conductividad eléctrica (CE): 1, 2 y 3 dS m-1 y dos niveles de poda (con y sin poda). Las variables evaluadas fueron: altura de planta (AP), diámetro de tallo (DT), número de hojas (NH) y de racimos (NR), flores por racimo (FLR), frutos por racimo (FR), peso de fruto (PF), rendimiento (REND) y lecturas SPAD. Resultados. Para ambas poblaciones, su cultivo en condiciones de invernadero e hidroponía promovieron el desarrollo en altura de planta, diámetro de tallo y peso de fruto. Se observó una variabilidad dentro y entre poblaciones para poda y conductividad eléctrica; el cultivo a 3 dS m-1 registró la menor altura de planta y el mayor diámetro de tallo, mientras que con 1 dS m-1 se obtuvo el mayor rendimiento; para el tratamiento con poda, los valores más altos se presentaron en flores por racimo, frutos por racimo y peso de fruto. Conclusiones. Ambas poblaciones presentaron el potencial para ser consideradas en estudios en ambientes controlados. Abstract Introduction. Jaltomata procumbens (Cav.) J. L. Gentry, used as food, is considered a semi-domesticated species (populations that have had a process of artificial selection but still have the ability to survive and reproduce without human intervention) and meets the criteria for future use. Objective. To evaluate agronomic traits of two J. procumbens populations, in greenhouse and hydroponics. Materials and methods. The research was carried out at the Colegio de Postgraduados, Campus Montecillo, Texcoco, State of Mexico, from July to December 2019. The following treatments were applied in an open hydroponic system: two populations (erect and decumbent), three electrical conductivity levels (CE): 1, 2, and 3 dS m-1 and two pruning levels (with and without pruning). The variables evaluated were: plant height (AP), stem diameter (DT), number of leaves (NH) and clusters (NR), flowers by clusters (FLR), fruits by clusters (FR), fruit weight (PF), yield (REND), and SPAD readings. Results. For both populations, their cultivation under greenhouse and hydroponic conditions promoted development in plant height, steam diameter, and fruit weight. Variability within and between populations was observed for pruning and electrical conductivity; the crop at 3 dS m-1 recorded the lowest plant height and the highest steam diameter, while at 1 dS m-1 the highest yield was obtained; for the pruning treatment, the highest values in flowers by cluster, fruit by cluster, and fruit weight were presented. Conclusion. Both populations showed the potential to be considered for studies in controlled environments.

Se estudió la evolución de la maduración de frutos de zapote mamey después de su tratamiento con gas etileno a 50 y 176 µL L-1 por 24 horas a 20 y 25º C. Todos los frutos presentaron el típico patrón climatérico de respiración y producción de etileno, cuyos valores máximos ocurrieron un día antes en la temperatura de 25 oC que a 20 oC. La aplicación de etileno exógeno afectó poco la velocidad de maduración pero mejoró la calidad de los frutos en el contenido de azúcares totales; el etileno tampoco afecto los cambios en firmeza, color (índice Tan-1 a/b), contenido de fenoles, ni las pérdidas de peso en relación al testigo.

El icaco (Chrysobalanus icaco L.) es una planta nativa, poco domesticada de América y África, distribuida en algunas zonas tropicales del mundo; sus usos son como alimento, medicinal y ornamental, principalmente. Sus frutos se caracterizan por tener diferencias morfológicas, particularmente en la pigmentación debida a la presencia de antocianinas. La identificación de estos compuestos serviría de base para estudios posteriores en el área quimiotaxonómica, ecológica y fisiológica. Por medio de técnicas cromatográficas en papel descendente y espectrales, se identificaron de forma cualitativa las antocianinas de los exocarpos de frutos rojos como cianidina 3-arabinósido y a la delfinidina 3,5-diglucósido en los de frutos morados, por comparación con estándares obtenidos de fuentes conocidas.

Diseases, such as cancer, peptic ulcers, and diabetes, as well as those caused by drug-resistant infectious agents are examples of some of the world’s major public health problems. Amphipterygium adstringens (Schltdl.) Schiede ex Standl is an endemic tree to Mexico. Its stem bark has been used medicinally since pre-Hispanic times, but in recent decades it has been scientifically proven that it has properties that help counteract some diseases; extracts with organic solvents of the plant are outstanding for their anticancer, gastroprotective, and antimicrobial properties; terpenes and long-chain phenols have been identified as the main active compounds. Currently, overharvesting is causing a sharp reduction in natural populations due to an increase in demand for the stem bark by people seeking to improve their health and by national and transnational companies seeking to market it. Because of the growing interest of the world population and the scientific community, we reviewed recent studies on the bioactive properties of A. adstringens. Through the orderly and critical compendium of the current knowledge of A. adstringens, we provide a reference for future studies aimed at the rational use and protection of this valuable endemic natural resource.

Blocking virulence is a promising alternative to counteract Pseudomonas aeruginosa infections. In this regard, the phenomenon of cell-cell communication by quorum sensing (QS) is an important anti-virulence target. In this field, fatty acids (FA) have gained notoriety for their role as autoinducers, as well as anti-virulence molecules in vitro, like some saturated FA (SAFA). In this study, we analyzed the anti-virulence activity of SAFA with 12 to18 carbon atoms and compared their effect with the putative autoinducer cis-2-decenoic acid (CDA). The effect of SAFA on six QS-regulated virulence factors and on the secretion of the exoenzyme ExoU was evaluated. In addition, a murine cutaneous infection model was used to determine their influence on the establishment and damage caused by P. aeruginosa PA14. Dodecanoic (lauric, C12:0) and tetradecanoic (myristic, C14:0) acids (SAFA C12-14) reduced the production of pyocyanin by 35–58% at 40 and 1,000 µM, while CDA inhibited it 62% at a 3.1 µM concentration. Moreover, the SAFA C12-14 reduced swarming by 90% without affecting biofilm formation. In contrast, CDA reduced the biofilm by 57% at 3 µM but did not affect swarming. Furthermore, lauric and myristic acids abolished ExoU secretion at 100 and 50 µM respectively, while CDA reduced it by ≈ 92% at 100 µM. Remarkably, the coadministration of myristic acid (200 and 1,000 µM) with P. aeruginosa PA14 induced greater damage and reduced survival of the animals up to 50%, whereas CDA to 500 µM reduced the damage without affecting the viability of the PA14 strain. Hence, our results show that SAFA C12-14 and CDA have a role in regulation of P. aeruginosa virulence, although their inhibition/activation molecular mechanisms are different in complex environments such as in vivo systems.

A profile of endogenous hormones and sugars in leaves and pseudobulbs of Laelia anceps subsp. anceps (Orchidaceae) plants induced and non-induced to flowering by the effect of different doses of exogenous gibberellic acid (GA3), considering the current and back growth structures (CGS and BGS), were investigated. A factorial experiment with five doses of GA3 and two growth structures was designed. Adult plants with undifferentiated vegetative buds were selected and sprayed with doses of 0, 400, 600, 800, and 1000 mg GA3 L−1. The main results showed a strong interaction between GA3 dose and growth structures, which promoted the highest kinetin (KIN) concentration in CGS. Exogenous GA3 increased endogenous GA3 in leaves and pseudobulbs induced (I-Leaf and I-PSB) and non-induced (NI-Leaf and NI-PSB) to flowering. For sugar concentration, the 400 mg L−1 GA3 dose promotes significant interaction with the CGS in NI-PSB. In general, the hormone profile revealed opposite balances of endogenous hormone concentrations for KIN, zeatin (ZEA), trans-zeatin (T-ZEA), indoleacetic acid (IAA), indole-3-butyric acid (IBA) and GA3, not only for growth structures but also for vegetative organs analyzed, depending on whether the plants were induced or not induced to flowering, with the highest concentration of endogenous hormones in pseudobulbs. Likewise, different sugar concentration balances were observed. These balances of both endogenous hormones and sugars are likely to be involved in the flowering of L. anceps.

Introducción: La vainilla (Vanilla planifolia Jacks. ex Andrews), es una orquídea cuyo fruto beneficiado presenta características organolépticas sobresalientes, siendo la segunda especia más costosa después del azafrán y utilizada como saborizante y aromatizante. Debido a cambios en el patrón climático en la región productora del Totonacapan, en Veracruz, México, la productividad de la vainilla ha disminuido, pero en otras regiones como la Huasteca Potosina, la producción comercial representa una opción para los productores locales. Por lo anterior en este estudio se evaluó la calidad de la vainilla procedente de 14 sitios de once localidades, pertenecientes a ocho municipios de la Huasteca Potosina, San Luis Potosí, México.Método: Se cosecharon frutos de vainilla de cada localidad, en madurez fisiológica de 32 semanas de edad (224 días después de polinización), y se sometieron a un mismo proceso de beneficio y posteriormente se evaluaron variables como dimensión, porcentaje de humedad, actividad de agua, contenido de azúcares solubles totales y compuestos del aroma en el fruto beneficiado.Resultados: Se encontró que el azúcar predominante en frutos de vainilla beneficiado fue la glucosa, con 1.55-4.28 %. Los frutos provenientes del 60% de los lugares de colecta cumplieron con la norma de longitud mínima. El ácido vaníllico fue el componente del aroma con mayor variación. El contenido de vainillina de los frutos provenientes de todos los municipios tuvieron más de 1.2 %, y solo las muestras de fruto de dos sitios (Tixcuayuca3 y Tamala) cumplieron con el mínimo de 2.0 % que exige la NOM-182-SCFI-2011.Discusión y conclusión: Existe una variación significativa en el contenido de compuestos aromáticos, con una baja relación entre los compuestos del aroma (p-hidroxibenzóico, ácido vaníllico y p-hidroxibenzaldehído) y vainillina de 6.97-11.87 de los frutos de vainilla beneficiadas procedentes de 14 sitios de la Huasteca Potosina, México. Estas diferencias se consideran el resultado de la interacción del medio con la especie, condiciones del cultivo, nutrición, entre otras. A pesar de esto se pueden encontrar frutos que sobresalen por su calidad organoléptica, principalmente por el contenido de vainillina, como los frutos procedentes de los municipios de Matlapa, Xilita y Tamazunchale.

En la vainilla se sintetizan compuestos que presentan actividad antimicrobiana; no obstante, la variacion de fitoquimicos presentes en las estructuras vegetales de esta especie es poco conocida, en relacion con la condicion ambiental y el sistema de cultivo. El objetivo de esta investigacion fue cuantificar la variacion de fitoquimicos en hoja, tallo, flor, fruto verde y fruto beneficiado de dos quimiotipos (QI y QVI) de vainilla cultivados en acahual (vegetacion secundaria nativa e introducida) y malla sombra. Los quimiotipos de vainilla se recolectaron durante el periodo de floracion y a la cosecha en cuatro localidades de la region del Totonacapan, Mexico. La concentracion de compuestos fenolicos totales, taninos totales, taninos hidrolizables, taninos condesados, flavonoides, saponinas y triterpenos se analizo en extractos metanolicos por metodos espectrofotometricos. Los fitoquimicos se acumularon a diferente concentracion en los tejidos de la planta de vainilla en relacion con la condicion del sistema de manejo de cultivo y del quimiotipo. El cultivo en acahual favorecio la concentracion de compuestos fenolicos totales, taninos totales, hidrolizables y condensados, asi como de triterpenos totales; mientras que los valores obtenidos con malla sombra fueron mayores en saponinas. El QVI acumulo la concentracion mayor de fitoquimicos, con excepcion de los taninos hidrolizables que no mostraron diferencia estadistica entre quimiotipos. La condicion ambiental afecto la concentracion de fitoquimicos en las estructuras vegetales de la vainilla. La altitud fue la variable ambiental que mas impacto en la acumulacion de fitoquimicos, ya que mostro un efecto inverso en la concentracion de triterpenos totales, taninos totales y taninos condensados

Antecedentes y Objetivos: La germinación precoz (vivípara) de semillas en frutos de Stenocereus thurberi se ha correlacionado con mayor velocidad de germinación de las semillas remanentes. Esta investigación compara la germinación de cinco poblaciones de Sinaloa, México, para determinar: 1) si existe un patrón asociado con la germinación precoz de las semillas y 2) cuánto contribuye el fenómeno vivíparo a la germinación, dada la variación entre frutos, individuos y poblaciones de esta especie.Métodos: Se revisó el nivel de viviparidad de 194 plantas y se separaron las semillas en cuatro probables fuentes de varianza: poblaciones, categorías reproductivas (VV: vivíparas y NV: no vivíparas), plantas dentro de categorías y frutos dentro de plantas. Las respuestas de germinación final (PGF), tiempo medio (TMG), velocidad (VG) y sincronía de germinación (SG) se evaluaron en bloques al azar con tres repeticiones, en unidades experimentales de 25 semillas. Los datos se analizaron con ANOVA’s jerárquicos bajo un modelo lineal mixto.Resultados clave: Las categorías reproductivas explicaron 5-11% de la varianza y mostraron diferencias significativas a favor de las vivíparas, con PGF de 35 vs 19% y 91 vs 72%, VG de 1.5 vs 0.5 y 7.9 vs 5.4 semillas/día, y SG de 0.3 vs 0.1, 0.7 vs 0.5 y 0.8 vs 0.6. Las poblaciones de Buenavista y Tosalibampo tuvieron mayor porcentaje, velocidad y sincronía de germinación (prueba t de Student, P

El biodiesel producido a partir de semillas de Jatropha curcas es técnicamente viable, aunque existe poca experiencia a nivel nacional. Se desconoce si existe variación en los contenidos químicos de las semillas dependiendo del sitio de crecimiento (interacción genotipo-ambiente). Por tanto, el objetivo del presente estudio fue comparar la variación en características morfológicas y las variaciones en el contenido de aceite, proteína, esteres de forbol, índice de acidez, ácido oleico e índice de saponificación, en semillas de J. curcas recolectadas en diferentes zonas agroecológicas del estado de Veracruz y su réplica establecida en el Banco de Germoplasma (BG) del Campus Veracruz. Las semillas fueron recolectadas en agosto de 2013. Para los análisis químicos se usaron técnicas aprobadas por la AOAC. Para los análisis estadísticos se usó el programa Statistic versión 7 y Excel 2010. Se encontró una correlación significativa (r≤ 1) entre las variables morfológicas de las semillas, particularmente entre la longitud y peso (r≤ 0.75); la menor correlación fue entre ancho y largo (p≤ 0.36). El análisis de correlación entre el contenido de aceite y peso de semillas no fue significativo (p≤ 0.38). El promedio de aceite en Campo y BG fue de 38.5±5.8, de ácido oleico36±4.2, índice de saponificación 194±1.7, índice de acidez7.1±0.8, proteína24.3±3.7, esteres de forbol 0.34±1.04. Se concluye que hubo diferencias significativas para la variable esteres de forbol en las condiciones de campo y BG, siendo mayores las concentraciones en las semillas de campo.

Context: Sechium edule (Jacq.) Sw. (Cucurbitaceae) is used in ethnomedicine, but the diversity of the varietal groups of this species has not often been considered. This is important because we previously reported that different variety of species exhibit different activities across different tumor cell lines. Objective: This study investigates the chemical composition and biological activities of extracts obtained from S. edule var. nigrum spinosum. Materials and methods: The leukemia P388 cell line and mononuclear bone marrow cells (MNCBMs) were treated with the extract at a concentration ranging from 40 to 2370 μg/mL for cytotoxicity and viability assays. CD-1 mice were treated with 8–5000 mg/kg extract and monitored every hour for the first 24 h and subsequently for seven days for signs of toxicity (LD50). In addition, the chromatographic profile of the extract was determined by HPLC. Results: The extract inhibits the proliferation of both P388 cells and MNCBMs, with IC50 values of 927 and 1911 μg/mL, respectively, but reduced the viability and induced the apoptosis of only leukemia cells. The LD50 was higher than 5000 mg/kg, and this concentration did not alter the blood chemistry or cell count but doubled the mitotic index in the bone marrow. The HPLC showed the presence of cucurbitacins, phloridzin, naringenin, phloretin, apigenin, and gallic, chlorogenic, vanillic, p-hydroxybenzoic, caffeic, and p-coumaric acids. Discussion and conclusion: Sechium edule var. nigrum spinosum contains bioactive compounds that explain the antiproliferative and nutraceutical activities, and its lack of physiological side effects constitutes an added value to a widely consumed vegetable.

La resina de Liquidambar styraciflua (Altingiaceae) fue colectada en temporada de sequía y lluvia durante 2013, en las comunidades Santa Lucía, Tianguistengo, Xochimilco y Xalapa en el estado de Hidalgo, México. El aceite esencial de la resina se obtuvo por hidrodestilación. Xalapa obtuvo el mejor rendimiento de aceite esencial con 9.3 %, en época de sequía. La resina y el aceite se analizaron por cromatografía en capa fina y cromatografía de gases acoplada a espectrometría de masas, respectivamente. El análisis por cromatografía en capa fina mostró mayor número de compuestos en época de sequía. Se calculó la relación de frentes en ambas temporadas, algunos valores coincidieron con los valores reportados para los ácidos cinámico y benzoico, así como del cinamato de cinamilo. Un total de 52 compuestos fueron encontrados por cromatografía de gases acoplada a espectrometría de masas, los cuales variaron en cada temporada. Los compuestos mayoritarios correspondieron al alcohol dihidro cinámico, estireno, cardeno, alcohol de cinamilo y alfa-pineno. Tres de los compuestos encontrados han sido reportados en el aceite esencial de hojas y tallos de L. styraciflua , estos son el beta-mirceno, allo-aromadendreno y gama-cadineno. Los compuestos principales encontrados en los aceites esenciales coinciden entre las diferentes procedencias, por lo que el aprovechamiento comercial del styrax mexicano debe ser viable desde el punto de vista de su composición.

Fruits of chayote [Sechium edule (Jacq.) Swartz] are widely consumed in Mesoamerica, but little is known about the nutraceutical potential. This study aimed to determine the chemical compositions, antioxidant activities from the juice fruits from two commercial varieties of chayote cultivated in Mexico, as well as a proposal for the elaboration of chayote juices with stevia leaves and pineapple juice. The physicochemical properties of juice from virens levis (VL) and nigrum spinosum (NS) varieties were determined using standard methods. The juice of the two varieties differ significantly regarding the concentrations of total soluble solids, total sugars, but not vitamin C. The total concentration of phenolics in NS extracts was slightly higher than in VL (1005 and 856 mg 100 g−1 dry-weight, respectively) but the total flavonoid contents were similar (27 and 26 mg 100 g−1 dry-weight, respectively). Cucurbitacin D was predominant in both varieties. The radical scavenging capacities of VL and NS extracts varied slightly (IC50 = 0.45 to 0.65 mg mL−1), while the antioxidant activities were similar (~80%). The NS variety is particularly promising regarding nutraceutical application. The chayote juice combined with stevia and pineapple maintain the original nutraceutical characteristics from the fruit, but enhanced the organoleptic characteristics like density and sugar/acidity balance.

La hidrodestilacion, extraccion con disolvente organico y enfleurage son tecnicas comunes para la extraccion de aceites esenciales a partir de muestras vegetales. Un factor que influye en el rendimiento de la extraccion de aceite esencial es el metodo utilizado. El objetivo de este estudio fue el de comparar tres metodos para la extraccion de aceite esencial de capitulos de calendula, con base en el rendimiento de aceite, el tiempo de procesamiento, y el numero de compuestos extraidos, con fines de investigacion centrados en caracterizacion genotipica de este tipo de materiales. Los rendimientos de los aceites esenciales obtenidos por hidrodestilacion, extraccion con disolvente organico y enfleurage fueron 0.9 ± 0.1, 6.7 ± 0.2 y 7.1 ± 0.15 g de aceite por 100 g de material floral seco, respectivamente. El metodo que proporciona el aceite de mas alta calidad (sin pigmentos) fue la hidrodestilacion, que tambien contuvo la mayor cantidad de compuestos no polares, aunque requiere mucho tiempo para procesar muchas muestras de forma simultanea. La extraccion con disolventes organicos y enfleurage son mas rapidos para su procesamiento, pero los aceites extraidos a traves de ellos contienen pigmentos. La tecnica mas conveniente para procesar muchas muestras en un corto periodo de tiempo fue el enfleurage, porque proporciono un rendimiento de aceite siete veces mayor que la hidrodestilacion y un aceite con menos pigmentos que la extraccion con disolvente organico. Ademas, el aceite obtenido por enfleurage contenia los dos compuestos principales en flores de calendula, α–cadineno y δ–cadineno

"In vanilla, compounds that exhibit antimicrobial activity are synthesized; however, the variation in phytochemicals present in the plant structures of this species is little known, in relation to the environmental condition and the crop system. The objective of this research was to quantify the variation in phytochemicals in leaf, stem, flower, green fruit and cured fruit from two vanilla chemotypes (QI and QVI) grown in acahual (native and introduced secondary vegetation) and shade mesh systems. Vanilla chemotypes were collected during the flowering period and at harvest in four locations in the Totonacapan region, Mexico. The concentration of total phenolic compounds, total tannins, hydrolysable tannins, condensed tannins, flavonoids, saponins and triterpenes was analyzed in methanolic extracts by spectrophotometric methods. The phytochemicals accumulated at different concentrations in the vanilla plant tissues in relation to the condition of the crop management system and the chemotype. Acahual cultivation favored the concentration of total phenolic compounds, total, hydrolysable and condensed tannins, and total triterpenes, while the values ​​obtained with shade mesh were higher in saponins. QVI accumulated the highest concentration of phytochemicals, with the exception of hydrolysable tannins that showed no statistical difference between chemotypes. The environmental condition affected the phytochemical concentration of phytochemicals in the plant structures of vanilla. Elevation was the environmental variable that most impacted the accumulation of phytochemicals, since it showed an inverse effect on the concentration of total triterpenes, total tannins and condensed tannins."

Domestication is an evolutionary process that culminates with the origin of individuals or populations that are morpho-physiologically, chemically and genetically different from their wild, congeneric relatives. The aim of the present study was to quantify the inter- and intra-specific variation in fruit biomass, number of seeds, and physical characteristics of seeds in O. streptacantha Lem., O. hyptiacantha F.A.C. Weber, O. megacantha Salm-Dyck, O. albicarpa Scheinvar and O. ficus-indica (L.) Mill., the least, intermediate, and most highly domesticated species. The hypothesis was that selecting larger fruits with fewer and softer seeds (normal and aborted) during domestication reduced the interspecific variation in fruit biomass, number of seeds, and physical characteristics of seeds in Opuntia spp., Cactaceae. For fruits of 89 variants of the Southern Mexican Plateau, total biomass and biomass of pulp with seeds was quantified; seed length, width, thickness and dehydrated mass were measured, as well as hardness of normal seeds. The total number of seeds was quantified and normal and aborted seeds were counted separately. A randomized design, with 89 treatments (variants) and six replicates and a fruit as experimental unit per treatment was used. The data were analysed by ANOVA, Tukey’s multiple comparison test (p ≤ 0.05), multivariate ordination (principal components analysis) and classification (clustering analysis). Inter-specific analysis indicated that fruits of the most highly domesticated variants (O. albicarpa and O. ficus-indica) had higher biomass (p ≤ 0.05), followed by those of O. hyptiacantha and O. megacantha and wild variants of O. streptacantha, and non-significant differences existed in seed thickness or hardness. Fruit and pulp biomass were positively and significantly correlated with seed biomass. Species with greater domestication clustered according to their larger fruits (≥117.83 g) and the greater number of aborted seeds (≥65). Domestication of Opuntia has also modified seed dimensions and increased the number of aborted seeds per fruit (≤11 to ≥65).

Fruits of chayote [Sechium edule (Jacq.) Swartz] are a non-traditional vegetable widely consumed in Latin America, with the state of Veracruz, México being the world’s main producer, but little is known about the nutraceutical potential. This study aimed to determine the chemical compositions and antioxidant activities from the juice fruits from two commercial varieties of chayote cultivated in Mexico, as well as a proposal for the elaboration of chayote juices with stevia leaves and pineapple juice. The physicochemical properties of juice from virens levis (VL) and nigrum spinosum (NS) varieties were determined using standard methods. The juice of the two varieties differ significantly regarding the concentrations of total soluble solids and total sugars, but not vitamin C. The total concentration of phenolics in NS extracts was slightly higher than in VL (1005 and 856 mg 100 g−1 dry-weight, respectively), but the total flavonoid contents were similar (27 and 26 mg 100 g−1 dry-weight, respectively). Cucurbitacin D was predominant in both varieties. The radical scavenging capacities of VL and NS extracts varied slightly (IC50 = 0.45 to 0.65 mg mL−1), while the antioxidant activities were similar (~80%). The NS variety is particularly promising regarding nutraceutical application. The chayote juice combined with stevia and pineapple maintained the original nutraceutical characteristics of the fruit, but enhanced the organoleptic characteristics like density and sugar/acidity balance.

Resumen es: La pulpa del fruto de zapote mamey contiene cantidades considerables de carotenoides y compuestos fenolicos, recientemente el consumo de estos metabolit...

Bioenergy production combined with phytoremediation has been suggested to help in solving two critical world problems: the gradual reduction of fossil fuels and soil contamination. The aim of this research was to investigate the potential for the use of Ricinus communis L. (castor oil plant) as an energy crop and plant species to remediate metal-polluted sites. This study was performed in mine tailings containing high concentrations of Cu, Zn, Mn, Pb and Cd. Physico-chemical characterization, total, DTPA-extractable and water-soluble metals in rhizospheric tailings heap samples were carried. Metal concentrations in plant tissues and translocation factors (TFs) were also determined. The Ricinus seed-oil content was high between 41 and 64%, seeds from San Francisco site 6 had the highest oil content, while these from site 7 had the lowest. No trend between oil yield vs seed origin site was observed. Seed-oil content was negatively correlated with root concentration of Cu, Zn, Pb and Cd, but no correlation was observed with the extractable-metals. According to its shoot metal concentrations and TFs, castor bean is not a metal accumulator plant. This primary colonizing plant is well suited to cope with the local toxic conditions and can be useful for the stabilization of these residues, and for then decreasing metal bioavailability, dispersion and human health risks on these barren tailings heaps and in the surrounding area. Our work is the first report regarding combined oil production and a phytostabilization role for Ricinus plants in metal mine tailings and may give a new value to suitable metal-polluted areas.

This paper describes the implementation of a strategy to develop identification of Lupinus cultivars with fatty acid methyl esters relation about alkaloids. The genus Lupinus is abundant in Mexico, Lupinus uncinatus is an endemic plant of Mexico, and this has not been studied in terms of chemical composition and information about length, width and weight from seeds. This work is focused on analyzing the content of fatty acids methyl esters from L. uncinatus seeds. Where it was determined percentage oil as well as the concentration of twenty two fatty acid methyl esters and their corresponding equivalence TUFA (Total Saturated Fatty Acid), MUFA (Monounsaturated Fatty Acids) and PUFA (Polyunsaturated Fatty Acid). As a result of the analysis of lupine seeds, it was observed that the behavior of sweet spices versus bitter species has an ongoing relationship, with a higher content of PUFA (bitter) to higher MUFA (sweet) and measures of seeds.

Existe poca información acerca del uso de dietas con baja proteína cruda (PC) para cerdos en iniciación. Por tanto, se realizaron dos experimentos para determinar el porcentaje mínimo de PCen dietas sorgo-pasta de soya que no afecte el comportamientoproductivo, utilizando urea en plasma como indicador. En el experimento 1, los tratamientos (% PC) fueron: T1) testigo 20.5;T2) 19.0; T3) 17.5; T4) 16.0; T5) 14.5, y se aplicaron a 10 cerditasen iniciación usando un diseño cruzado con periodos de 7 d. El último día de cada periodo se obtuvo una muestra de sangre de la vena cava para determinar urea. La menor concentración deeste metabolito indicó que la PC en la dieta puede reducirse hasta 16%. Mediante regresión no lineal exponencial se determinó que la PC en la dieta se puede reducir hasta 14.86% y aumentar hasta 20.12% para obtener la mínima y máxima concentración de urea en plasma. En el experimento 2, los tratamientos(%PC y Mcal EM kg #8722;1) fueron: T1) dieta estándar, 20.5 y 3.265;T2) 20.5 y 3.165; T3) 16 y 3.265; T4) 16 y 3.165; T5) 14.5 y3.265; T6) 14.5 y 3.165, para 24 machos castrados usando undiseño en bloques completos al azar. El menor nivel de proteína redujo la urea en plasma, mientras que al reducir la energía disminuyó la grasa dorsal y aumentó la conversión alimenticia. Lo anterior indica que la urea se reduce al disminuir la PC en ladieta; que la grasa dorsal es menor al bajar la energía; y queotros factores como el peso inicial también influyen en la respuesta de los cerdos en iniciación.

En frutos de zapote mamey (Pouteria sapota (Jacq.) H. E. Moore and Stearn) se estudió la maduración a temperatura ambiente (20 °C; 50-60 % HR) y el comportamiento de este proceso durante y después del almacenamiento a bajas temperaturas (5, 10 y 15 °C; 80-85 % HR). Durante el cambio de madurez fisiológica a madurez de consumo en los frutos de zapote mamey almacenados a 20 °C por 12 d los fenoles totales disminuyeron de 1653 a 646 mg kg-1 y la actividad de polifenol oxidasa (PFO) se incrementó de 23.8 a 53.1 U g-1, y al mismo tiempo disminuyó la astringencia. La peroxidasa (POD), catalasa (CAT) y superóxido dismutasa (SOD) incrementaron su actividad de la madurez fisiológica a la madurez de consumo, de 383 a 2104, de 11.4 a 21 y de 6.7 a 28.5 U g-1, respectivamente. La proteína soluble aumentó de 82 en la madurez fisiológica a 950 mg kg-1 en la madurez de consumo. El almacenamiento a 5 °C retrasa la disminución de los fenoles totales (555.6 mg kg-1) e inhibió la actividad de PFO (11.2 U g-1) 8 d después de haber sido transferidos a 20 °C; disminuyó la actividad enzimática de CAT (14.5 U g-1) y SOD (6.4 U g-1), así como la concentración de la proteína soluble (251.7 mg kg-1) durante el mismo periodo. POD fue inhibida durante el almacenamiento, pero alcanzó valores similares al testigo (2443.4 U g-1) 8 d después transferirse a 20 °C. El almacenamiento a 10 °C provocó efectos similares que la temperatura de 5 °C pero en menor intensidad. Los frutos almacenados a 15 °C no fueron afectados negativamente en sus actividades enzimáticas, proteína soluble y concentración de fenoles totales. Por tanto, la inhibición de la actividad de enzimas antioxidantes fue afectada negativamente por el almacenamiento a temperaturas menores de 10 °C y estuvo asociada a daños por frío en frutos de zapote mamey.

El cultivo de la papaya (Carica papaya L.) cv. Maradol es afectado por factores de origen biótico y abiótico, que repercuten en el vigor, la sanidad, el rendimiento y la apariencia del fruto. El objetivo de la presente investigación fue evaluar el efecto de la fertilización orgánica e inorgánica al suelo y foliar, sobre algunas variables fisiológicas de plantas de papaya, concentración nutrimental en hojas, rendimiento y características de los frutos producidos. Los resultados obtenidos revelaron que la fertilización mineral afectó significativamente la altura de planta, el diámetro de tallo, los frutos en las secciones inferior y media de la copa, total de frutos y el rendimiento. En cambio, la producción de frutos deformes, frutos en la sección superior de la copa y la altura a primer fruto, no fueron afectados por la fertilización orgánica y mineral al suelo o foliar. Las mayores concentraciones de calcio se encontraron en hojas de plantas con fertilización orgánica (22.4 ¿g g-1), magnesio en plantas con fertilización foliar (11.8 ¿g g-1) y boro en aquéllas con fertilización orgánica (0.133 ¿g g-1) y mineral (0.130 ¿g g-1).

En frutos de zapote mamey (Pouteria sapota (Jacq.) H. E. Moore and Stearn) se estudió la maduración a temperatura ambiente (20 °C) y el comportamiento de este proceso durante y posterior al almacenamiento a bajas temperaturas (5, 10 y 15 °C). Los frutos de zapote mamey almacenados a 20 °C por 12 d con una humedad relativa de 50-60 %, presentaron un máximo de CO2 (85.3 mL kg-1 h-1) y uno de etileno (258.7 µL kg-1 h-1), así como aumentos en la acumulación de acetaldehído y etanol de 21.9 y 6.4 en madurez fisiológica a 62.7 y 99.7 mg kg-1 en madurez de consumo, respectivamente; incremento en la concentración de azúcares totales de 82.7 a 267.3 mg g-1, pérdidas diarias de peso de 1.02 % y disminución de firmeza de 30 a 1-4 N. El almacenamiento a 5 °C y humedad relativa de 85 % por 20 d causó daños por frío en los frutos, debido a aumentos de 72.8 y 47.5 %, en las tasas de respiración y de producción de etileno con respecto al testigo; menor acumulación de etanol y acetaldehído (50 y 46.6 mg kg-1), menor acumulación de azúcares totales (200 mg g-1) y menor ablandamiento (21.8 N), a los 8 d después de haber sido transferidos a temperatura ambiente. Los síntomas visibles del daño por frío fueron la presencia de áreas oscurecidas en la pulpa, incapacidad de desarrollar el color característico, y zonas acuosas y endurecidas cerca de la semilla. El almacenamiento a 10 °C provocó daños por frío en menor intensidad, mientras que los frutos almacenados a 15 °C no presentaron daños por frío. Las pérdidas de peso se elevaron al aumentar la temperatura de almacenamiento, pero después de transferirse a temperatura ambiente las pérdidas diarias de peso fueron de 1.08 % y similares entre tratamientos.

En frutos de zapote mamey (Pouteria sapota (Jacq.) H. E. Moore and Stearn) se estudió la maduración a temperatura ambiente (20 °C; 50-60 % HR) y el comportamiento de este proceso durante y después del almacenamiento a bajas temperaturas (5, 10 y 15 °C; 80-85 % HR). Durante el cambio de madurez fisiológica a madurez de consumo en los frutos de zapote mamey almacenados a 20 °C por 12 d los fenoles totales disminuyeron de 1653 a 646 mg kg-1 y la actividad de polifenol oxidasa (PFO) se incrementó de 23.8 a 53.1 U g-1, y al mismo tiempo disminuyó la astringencia. La peroxidasa (POD), catalasa (CAT) y superóxido dismutasa (SOD) incrementaron su actividad de la madurez fisiológica a la madurez de consumo, de 383 a 2104, de 11.4 a 21 y de 6.7 a 28.5 U g-1, respectivamente. La proteína soluble aumentó de 82 en la madurez fisiológica a 950 mg kg-1 en la madurez de consumo. El almacenamiento a 5 °C retrasa la disminución de los fenoles totales (555.6 mg kg-1) e inhibió la actividad de PFO (11.2 U g-1) 8 d después de haber sido transferidos a 20 °C; disminuyó la actividad enzimática de CAT (14.5 U g-1) y SOD (6.4 U g-1), así como la concentración de la proteína soluble (251.7 mg kg-1) durante el mismo periodo. POD fue inhibida durante el almacenamiento, pero alcanzó valores similares al testigo (2443.4 U g-1) 8 d después transferirse a 20 °C. El almacenamiento a 10 °C provocó efectos similares que la temperatura de 5 °C pero en menor intensidad. Los frutos almacenados a 15 °C no fueron afectados negativamente en sus actividades enzimáticas, proteína soluble y concentración de fenoles totales. Por tanto, la inhibición de la actividad de enzimas antioxidantes fue afectada negativamente por el almacenamiento a temperaturas menores de 10 °C y estuvo asociada a daños por frío en frutos de zapote mamey.