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El uso de películas comestibles es una tecnología para alargar la vida útil de los alimentos. La adición de nanopartículas de plata (AgNPs) podría mejorar el desempeño de películas comestibles y evitar el crecimiento de microorganismos que podrían afectar a los alimentos. El objetivo fue elaborar y caracterizar AgNPs mediante síntesis verde y evaluar el efecto de su adición sobre las propiedades mecánicas y de barrera de películas formadas a partir de proteína de Cajanus cajan y goma de la semilla de Tamarindus indica. Para la síntesis de AgNPs se utilizó extracto acuoso de Annona muricata. Tres diferentes formulaciones de películas se elaboraron las cuales contenían AgNPs, extracto acuoso de guanábana y agua (control). Las películas fueron evaluadas en términos de su permeabilidad al vapor de agua (WVP), color, opacidad y propiedades mecánicas. Las AgNPs incrementaron el doble el módulo de Young de las películas (0.0675 MPa) y la fuerza de tensión (2.84 MPa) con respecto al control. Además, las AgNPs influyeron estadísticamente en el color y opacidad de la película. Sin embargo, no se observaron diferencias en la PVA. La adición de AgNPs a recubrimientos podría ser una opción para incrementar la vida útil de alimentos.

In Chiapas, Mexico, there are high-yielding coffee plants adapted to the local climatic conditions. The presence of microorganisms in the explants makes developing protocols for cloning these genotypes in vitro difficult. The objective of this work was to evaluate how field and in vitro microorganism management affected asepsis and the induction of callogenesis in leaf explants of agronomically important coffee plants. Drought-tolerant genotypes were obtained from aseptic explants and cell cultures using a participatory study, agronomic, and in vitro techniques. Five accessions (ITTGj 1-5) were selected from a 21-year-old Borbon cultivar. The present study was conducted over two flowering cycles, evaluating the effect of field management on explant asepsis on the first and the callogenic response caused by the culture medium, the transport solution, and the genotype, on the second. Sixty days before explant collection, biweekly applications of calcium polysulfide (10 % v v-1), copper oxychloride (2 g L-1), and Zingiber officinale extract (20 g L-1) reduced fungal contamination by 100 % and bacterial contamination by 90 %. Field explant transportation in 200 mg L-1 citric acid and ascorbic acid solution reduced oxidation in explants and in vitro cultures. Proembryogenic friable corns were formed with the combination of 4.4 µM BAP (6-benzylaminopurine) and 7.25 µM 2,4-D (2,4-dichlorophenoxyacetic acid) at 45 days of culture, with genotype four showing the best response. Field management was effective for the aseptic establishment of Coffea arabica cultures in vitro, and the combination of BAP and 2,4-D used was an appropriate growth regulator for the induction of callogenesis.

The improvement of the symbiosis generated by arbuscular mycorrhizal fungi (AMF) against pathogenic microorganisms has been described, however, the ef fect of AMF in peanut crops is of interest due to the value of the productive chain that has not been fully attended. Therefore, this research work evaluated six treatments: (T1) Control plants without AMF, (T2) Plants with vermicompost leachate, (T3) Plants inoculated with commercial mycorrhizae, (T4) Plants inoculated with native mycorrhizae, (T5) Plants inoculated with commercial mycorrhizae + leachate and (T6) Plants inoculated with commercial mycorrhizae + native mycorrhizae; in this sense, mycorrhizal fungi were isolated, identifying Rhizoglomus clarum, Acaulospora alpina and Acaulospora af f. bireticulata, and inoculated in peanut plants in an area of 144 m2 in the open, so that, to corroborate the incidence of the treatments evaluated, agronomic variables such as height, width of biomass, foliar damage by Cercospora personata, number of f lowers, were evaluated during the pre-harvest every 15 days and the post-harvest variables were; leaf area index, root length, fruit and lipid yield, as well as the prof ile of fatty acids present in the fruit. Finally, peanut quality was evaluated according to CODEX STAN 200-1995, showing that the best treatment was leaching + commercial mycorrhizae, reporting yields of 65.05% of fruits and 58% of total lipids, mostly monounsaturated fatty acids (52 % oleic acid) followed by polyunsaturated (21% linoleic acid), f inally according to CODEX STAN 200-199 the peanuts obtained correspond to the basic quality with dimensions of 4 to 4.5 cm wide and long respectively, these peanuts cannot be exported but they can be marketed in the country for agro-industrial transformation, allowing improved agricultural practices by reducing the use of agrochemicals.

The use of phytonanoparticles in agriculture could decrease the use of fertilizers and therefore decrease soil contamination, due to their size being better assimilated in plants. It is important to mention that the nanofertilizer is slow-releasing and improves plant physiological properties and various nutritional parameters. The influence of soil and foliar applications of phytonanoparticles of ZnO with the Moringa oleifera extract under three concentrations (25, 50, and 100 ppm) was evaluated on the cherry tomato crop (Solanum lycopersicum L.). Synthesis of the phytonanoparticles was analyzed with ultraviolet-visible spectroscopy (UV-Vis) and infrared transmission spectroscopy with Fourier transform (FT-IR), as well as the analysis with the dynamic light scattering (DLS) technique. The morphometric parameters were evaluated before and after the application of the nanoparticles. The minerals’ content of fruits was done 95 days after planting. Results showed that soil application was better at a concentration of 25 ppm of phytonanoparticles since it allowed the greatest number of flowers and fruits on the plant; however, it was demonstrated that when performing a foliar application, the fruit showed the highest concentrations for the elements Mg, Ca, and Na at concentrations of 511, 4589, and 223 mg kg−1, respectively.

A modified method for the direct extraction of DNA from alkaline-saline soils with minimum DNA fragmentation and a possible reduction in chimera formation during polymerase chain reaction (PCR) was developed. The commercial extraction kit Power Soil DNA (Mo Bio™ Laboratories, Inc.) was used as a reference technique. The method reported here was based on cell lysis employing ethylenediaminetetraacetic acid (EDTA), sodium dodecyl sulfate (SDS), and cell disruption with mechanical force with FastPrep-24™ equip followed by one cycle of freezing at -40 °C for 60 min and thawing at 65 °C for 20 min. The extraction method was tested for allophonic soils with large concentrations of organic matter, fulvic and humic acids, electrolytic conductivity (EC) ranging between 2.6 dS m-1 and 39.9 dS m-1, and pH between 8.8 and 10.9. The yield of DNA extracted depended on soil type, i.e., DNA extracted from soil varied between 2.35 (Texcoco-2) to 3.66 (Texcoco-1) μg DNA g-1 soil. The proposed method in this study produced enough DNA with yield and quality for PCR amplification of 16S rDNA when bovine serum albumin (BSA) was added to the reaction buffer. The DNA obtained had sufficient quality and yield for later use for 16S sequencing or possible use in other sequencing technologies, e.g. whole metagenome shotgun sequencing.

Agave (Agave tequilana var. azul) is considered a crop with low genetic diversity because it has been propagated vegetatively for centuries for commercial purposes, and consequently, it could be equally susceptible to pests and diseases. However, the present study employs plant material derived from field-grown plants exhibiting phenotypic variability in susceptibility to agave wilt. The offshoots from rhizomes of these plants were reproduced in vitro and classified as potentially resistant or susceptible. Amplified fragment length polymorphism analysis confirmed wide genetic differences among individuals, but these differences were not correlated with the observed phenotypic variability in resistance. Propagated plantlets were inoculated with Fusarium solani in two time-lapse confrontations for 72 h and 30 days. The early biochemical response showed statistically superior levels in the accumulation of shikimic acid, phenolic compounds, and chitinase activity in potentially resistant plantlets. There was an inverse correlation of these early biochemical responses and salicylic acid and the incidence of diseased root cells in isogenic plantlets in the 30-day confrontation with F. solani, suggesting that these activities and accumulation of molecules were primordial in the defence against this pathogen.

Las enfermedades causadas por Fusarium en Agave aumentan, lo cual significa importantes pérdidas económicas. Es necesario entonces buscar alternativas en la prevención y control de pató­genos para reducir el uso de fungicidas químicos, y así promo­ver un tipo de control de enfermedades que sea amigable con el ambiente. Los aceites y extractos de hojas de algunas plantas son eficientes en el control de plagas y enfermedades. Piper auritum (“hierba santa”) contiene aceites esenciales que cumplen funcio­nes ecológicas, como las de atraer polinizadores y causar efectos alelopáticos. Baccharis glutinosa (“jarilla”) también se usa en el tratamiento de diversas enfermedades infecciosas. Hay diferentes extractos de plantas que tienen una actividad biológica contra microorganismos que afectan cultivos importantes. El objetivo de esta investigación fue evaluar la actividad antimicrobiana del aceite esencial y extractos de dos plantas con uso tradicional en el estado de Chiapas sobre los hongos fitopatógenos (Fusarium spp.) de Agave spp. Los extractos de P. auritum y B. glutinosa se probaron contra los hongos fitopatógenos, como parte de un di­seño experimental completamente aleatorizado. Un ANOVA se realizó con seis tratamientos y tres repeticiones por tratamiento, utilizados en tres especies de Fusarium. El aceite esencial extraí­do de las hojas de Piper auritum tuvo el mayor efecto inhibi­dor significativo (96 h) sobre Fusarium oxysporum f. sp. comiteca (75.32%), Fusarium oxysporum f. sp. tequilana (86.57%) y Fu­sarium solani f. sp. comiteca (63.36%). Por lo tanto, P. auritum mostró un claro efecto fungistático.

Hydrocarbon contamination cause serious environmental damage and human health problems, therefore, to resolve this problem has been proposed diversely remediation techniques friendly with the environment i.e. bioaugmentation, biostimulation, natural attenuation and phytoremediation. Among options, the phytoremediation causes minimum alterations to soil, low cost, it has proved good eff iciency and gained public acceptation. In the present study, the capacity of Mimosa pigra to restore a contaminated soil with both anthracene and phenanthrene was evaluated, along with the soil physicochemical changes due to both plant and contaminant presence in the soil. A silt-loam contaminated soil with 100 mg kg-1 (dry weight) anthracene and 200 mg kg-1 (dry weight) phenanthrene was used in all three treatments: Contaminated soil with M. pigra (C1), contaminated soil without M. pigra (C2), and not contaminated soil with M. pigra (C0) as control. After 70 days of experimentation both biomass and height of M. pigra was not affected due to soil contaminants. There was no difference among treatments for some physicochemical characteristics e.g. soil pH, electrolytic conductivity, soil-texture, and total nitrogen content throughout the experiment. M. pigra increased the soil water holding capacity after 50 and 70 days of the experiment, however, total organic carbon content was lower after 70 days compared to the control treatment. The higher contaminant removal rate was before 7 days of experimentation for all treatments. Anthracene and phenanthrene content were lower in treatments with the presence of M. pigra: 92% of phenanthrene and 80% of anthracene were removed in C1 while nearly 77% of phenanthrene and 60% of anthracene were removed in C2. This suggest a greater removal of contaminants using M. pigra. Total removal of contaminants was not achieved. However, M. pigra was able to accumulate both compounds, showing the M. pigra capability for bioremediation use in contaminated soils.

El chile xcat´ik (Capsicum annuum L.) es el segundo más consumido en la península de Yucatán, después del habanero. Los biofertilizantes microbianos son una opción factible de integrarse a los sistemas de producción para disminuir el uso de fertilizantes químicos. El objetivo del trabajo se basó en la evaluación del efecto de la aplicación de Bacillus subtilis, Trichoderma harzanium y un consorcio microbiano en las características agronómicas de la planta y la calidad del fruto del chile xcat´ik. El experimento se realizó en condiciones de invernadero, a través de un diseño experimental de bloques completos al azar con cuatro repeticiones. De acuerdo a los resultados se encontró que la aplicación de B. subtilis incrementó significativamente la altura de plantas respecto al testigo, así mismo la aplicación de B. subtilis y T. harzanium incrementó el volumen de raíz. Se observó que existen diferencias estadísticas en los contenidos de lípidos y proteínas en el fruto de plantas biofertilizadas con T. harzanium, y que en los frutos de plantas tratadas particularmente con B. subtilis y T. harzanium se acumulan mayores cantidades de fósforo.

Yam bean (Pachyrhizus erosus (L.) Urb.) tuber has a low carbohydrate content and contains several aminoacids, but contains few active compounds, such as vitamins and antioxidants. Anthocyanins are antioxidants found in Rubus fructicosus L. The osmotic drying is a technique that can be used to impregnate antioxidants in a matrix, so the objective of this study was to impregnate yam bean tuber slices with anthocyanin. The effect of temperature (40, 50 and 60oC), sucrose content (40, 50 and 60oBrix) and vacuum pulse (0, 300 and 600 mbar) on water loss (WL), solid gain (SG), color changes (ΔΕ) and anthocyanin concentration (ΔA) during osmotic drying of yam bean slices was determined. Polynomial equations were used to determine changes in WL, SG, ΔΕ and ΔA of yam bean slices after 6 h of osmotic drying. An osmotic solution at 60oC with a SC of 40oBrix, applying a vacuum pulse of 12 mbar maximized anthocyanin impregnation (6.67 mg anthocyanin per g initial dry matter) in tuber slices. The Page equation predicted optimum WL, SG and ΔA of yam bean tuber slices during osmotic drying. No relation was found between temperature, sucrose content and vacuum pulse with K and n parameters in the Page equation.

The carrot is considered a model system in plant cell culture. Spray drying represents a widely used technology to preserve microorganisms, such as bacteria and yeasts. In germplasm conservation, the most used methods are freeze drying and cryopreservation. Therefore, the aim of this work was to evaluate the effect of spray drying on the viability and totipotency of somatic carrot cells. Leaf, root and stem explants were evaluated to induce callus with 2 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D). Calli obtained from the stem were cultivated in a liquid medium with 1 mg/L of 2,4-D. Cell suspensions were spray dried with maltodextrin-gum Arabic and maltodextrin-xanthan gum mixtures, two outlet air temperatures (50 and 60 °C) and 120 °C inlet air temperature. Results showed that carrot cells were viable after spray drying, and this viability remained for six months at 8 °C. The totipotency of the microencapsulated cells was proven. Cells that were not spray dried regenerated 24.6 plantlets, while the spray dried cells regenerated 19 plantlets for each gram of rehydrated powder. Thus, spray drying allowed researchers to obtain viable and totipotent cells. This work is the first manuscript that reported the spray drying of plant somatic cells.

Agave (

Moringa oleifera is a highly versatile plant with potential use in the agro-food and biochemical industry. The goals of this study were to evaluate the effect of chemical fertilization and vermicompost on plant growth, and to analyze the metabolomic profile of M. oleifera crops cultivated over agricultural and native soils. The extracts were obtained from 90-day-old leaves via extraction with a hydroalcoholic mixture. Multivariate data analyses, such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA), were used to differentiate the distribution of leaf metabolites according to the soils or types of fertilizers used for the cultivation of Moringa oleifera. The results indicated that there was no significant effect on parameters such as plant height, root length and dry weight of leaves (p &lt, 0.05). UPLC-ESI-MS/MS analysis of leaf extracts revealed a wide range of flavonoids, alkaloids and organic acids. The results of PCA and PLS-DA confirmed that the type of fertilizer had an effect on the metabolomic profile of M. oleifera leaves. The application of vermicompost induced changes in the metabolomic profile, but not in the morphometric variables of Moringa oleifera. These results are important for metabolite production via organic cultures and over different soil types in the industrialization of Moringa.

This work was conducted with the objective to evaluate the effect of vermicompost application on chemical characteristics, energetic parameters and amino acids prof ile of hybrid race corn grain cultivated under open-f ield and rained conditions. The experiment was accomplished under a randomized complete design with three repetitions. Three treatments were evaluated: 1) Maize after inoculation with a commercial mycorrhizal arbuscular fungi mixture (Tec Myc 60®) plus vermicompost (V+M); vermicompost (V) and chemical fertilization (CF). Starch content in grain was 1.9% higher in V+M treatment in comparison with chemical, whereas crude protein, ether extract, crude f iber, acid detergent f iber, neutral detergent f iber, total phosphorous and phytic phosphorous were not different between treatments. Energetic parameters were not different between three treatments. 17 amino acids were evaluated of wich only tryptophan, leucine, valine, histidine and aspartic acid were higher in CF and V treatments in comparison with V+M treatment. In conclusion, it is possible to cultivate maize using vermicompost as fertilizer because chemical characteristics, energetic parameters and amino acids prof ile in maize grain were not affected compared with the maize cultivated with vermicompost added with biofertilizers (V+M) or with corn cultivated with chemical fertilizers (CF).

The objective of this work was to determine the effect of spray drying on the microbial survival of lactic acid bacteria (LAB), acetic acid bacteria (AAB) and yeast (Y), as well as on the volatile compounds retention of the “taberna”. Different mixtures of maltodextrin, gum arabic, xanthan gum and sodium alginate as coating materials, different proportions coating material:"taberna" (1:1, 1:2 and 1:3 v/v), as well as the effect of the feeding flow (3, 6 and 9 mL/min) and the inlet air temperature (80, 90 and 100 °C) in the dryer were evaluated on the efficiency of microencapsulation, microbial survival, water activity and the morphology of the microcapsules. Optimal conditions for the encapsulation of "taberna" to maximize microbial survival and microencapsulation efficacy were: feed flow of 3 mL/min, inlet air temperature of 97 °C and a mixture of MD-AG using a coating material:“taberna” ratio of 1:1 (v/v). With these conditions, in addition to maintaining the viability of the three microbial groups, most of the aromatic compounds of the "taberna" were retained.

Soy milk is a food rich in proteins, phenolic compounds and lactose-free. However, due to organoleptic and anti-nutritional characteristics, soy milk is not very popular among the population. The objective of this article is to evaluate the changes in the activity of α-galactosidase and β-glucosidase, as well as phytates, isoflavones, phenolic compounds contents and antioxidant activity of soy milk during the fermentation with Lactobacillus plantarum BAL-03-ITTG and Lactobacillus fermentum BAL-21-ITTG. Soy milk was fermented for 24 h with L. plantarum and L. fermentum separately, with an increase of 1.2 to 1.4 log CFU g-1 for both strains. The results showed that the strains are able to produce β-glucosidase, carrying out the conversion of β-glucosides in their corresponding aglycones, with an increase of 420 to 490 %. In addition, the strains can decrease approximately 20 % of the content of phytate in soy milk during fermentation. Therefore, both strains could be used in future works to obtain food from fermented soy milk.

Pesticide by-products found in soil are usually more toxic and persistent than the pesticides themselves. For example, Endosulfan lactone (EL) (a by-product of the organochloride pesticide endosulfan). EL is created by the enzymatic activity (and related oxidative processes) of microorganisms in the soil. A sustainable method of EL removal is the introduction of Eisenia fetida earthworm. In this paper, it will be demonstrated the impact of vermicomposting process related to Eisenia fetida earthworm on EL by measuring initial and final concentrations of the compound and overall enzymatic activity in sterile and non-sterile solid substrate over 56 days. As a baseline, it be observed there were higher EL removals in non-sterile solid substrate (90.86%) at day 5 than in sterile solid substrate (83.86%) at day 14. In samples with Eisenia fetida, the presence of EL in non-sterile solid substrate was 36%, however in sterile solid substrate it was only 18% at day 1 and 7, with a maximum enzyme activity of 0.4659 mmol/mg protein per min at day 7. The evidence found in this study suggests that EL removal in a non-sterile solid substrate is higher when a vermicomposting is present and that the influence of microorganisms from the solid substrate with the earthworm, increases removal.

La quitinasa y B-1,3-glucanasa desempeñan una función importante en la reacción de defensa contra patógenos fúngicos. En Agave americana existe poca información sobre el comportamiento de estas proteínas en respuesta a la infección de Fusarium oxysporum. En este estudio, se realizó un análisis de microscopía electrónica de barrido (MEB) en raíces de A. americana infectadas con F. oxysporum y se evaluó la actividad de quitinasa y B-1,3-glucanasa en raíces de A. americana a 0, 7, 15 y 30 días después de inoculación con F. oxysporum. MEB reveló que 15 días después de la inoculación (DDI) son suficientes para que el hongo infecte las raíces de A. americana. La actividad de quitinasa en plantas infectadas incrementó significativamente a los 15 DDI con respecto a las plantas no infectadas, mientras que la actividad de B-1,3 glucanasa no presentó diferencia estadística significativa con plantas testigo. Los resultados sugieren que, en respuesta a la infección por F. oxysporum, A. americana activa proteínas PRs de tipo quitinasas.

Las plantas utilizan diversos mecanismos para defenderse del ataque de hongos patogenos. Algunos de estos mecanismos incluyen el aumento de metabolitos secundarios, antioxidantes, enzimas hidroliticas y polisacaridos que causan la muerte o reducen la progresion de hongos patogenos. Hemileia vastatrix (roya del cafe) es un hongo biotrofo que causa graves danos a las plantaciones de cafe. Ocasionalmente, se pueden observar plantas con ausencia de sintomas. El estudio de estas plantas asintomaticas es de suma importancia para la conservacion y mejoramiento del germoplasma resistente a H. vastatrix . Para el estudio, aquellas plantas que durante la incidencia de la enfermedad no presentaban sintomas fueron denominadas no infectadas (Ni) y las que si los presentaban como infectadas (i). Se evaluaron dos periodos: antes de la infeccion por roya y durante esta, en plantas de Coffea arabica Ni e i cultivadas en campo bajo un sistema de produccion organico. Se determino la actividad enzimatica de quitinasa, β-1-3 glucanasa y peroxidasa; ademas, de la cuantificacion de fenoles totales, acido clorogenico (3-CQA), acido criptoclorogenico (4-CQA), acido neoclorogenico (5-CQA), acido ferulico (AF), acido cafeico (AC), acido galico (AG) y cafeina (Caf). No se encontraron diferencias (p

El Chichón is an active volcano located in the Chiapas Volcanic Arc characterized by high temperatures, low pH, and large heavy metal concentrations. High temperatures are known to affect microorganisms, so the bacterial community structure was investigated in crater-lake sediment at a ‘low’ 50 °C and a ‘high’ 92 °C by sequencing the 16S rRNA bacterial gene. Most metal concentrations, and bacterial richness, and diversity indexes were higher at 50 °C than at 92 °C. Fifteen phyla were found in the sediment at 50 °C dominated by Actinobacteria (33.1%), Proteobacteria (29.1%) and Acidobacteria (20.1%). Nine phyla dominated by Firmicutes (52.7%, mostly Alicyclobacillus and Sulfobacillus) and Proteobacteria (44.8%, mostly Bradyrhizobium, Methylobacterium, Sediminibacterium) were detected in the sediment at 92 °C. The predictive functional profiling indicated metabolic pathways related to amino acid metabolism, membrane transport, replication, and repair as the most important. It was found that although a large number of bacterial groups were well adapted to 92 °C, the higher temperature reduced strongly, the bacterial diversity and species richness in the El Chichón volcano crater-lake system, and altered the bacterial community structure and their functionality.

The aim of the present work is to evaluate the changes on the phenylalanine ammonia lyase (PAL) activity, phenolic compounds accumulation and photochemical efficiency in leaves of P. glandulosa treated with Cd2+ (0.001 M) and Cu2+ (0.52 M) concentrations for 96 h under hydroponic conditions. The results showed that only leaves treated with copper had a decrease in photochemical efficiency and leaf epidermal polyphenols in P. glandulosa leaves after 96 h of exposure. On the other hand the reverse-phase HPLC analysis revealed higher levels of phenolic compound (gallic, vanillic and caffeic acids) and flavonoids (rutin and kaempferol-3-O-glucosides) in plant leaves from Cu and Cd-treatments with respect to control plants. Finally, highest increments in PAL activity was observed in extracts of leaves treated with Cu and Cd (about 205 and 284%), respectively, with respect to control plants after 96 h treatment. These suggest that activation of phenylpropanoid pathway represent a source of nonenzymatic antioxidants that protect at P. glandulosa against oxidative stress when exposed to cadmium and copper. Hence future studies are necessary to elucidate the participation of phenylpropanoid pathway in the reduction of metal toxicity in Prosopis species.

Olive trees are one of the most important oil crops in the world due to the sensorial and nutritional characteristics of olive oil, such as lipid composition and antioxidant content, and the medicinal properties of its leaves. In this paper, callus formation was induced using nodal segments of olive tree (Olea europaea cv. cornicabra) as explants. Fatty acid profile, total phenolic compounds and total flavonoid compounds were determined in callus culture after 15 weeks and compared with leaf and nodal segments tissues. There was no statistical difference in phenolic compounds among leaf, nodal segments and callus culture, whereas flavonoid compounds were higher in leaf. Fatty acid profile was similar in leaf, nodal segments and callus culture and was constituted by hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, cis-9,12-octadecadienoic acid, cis-9,12,15-octadecatrienoic acid. Hexadecanoic acid was the main fatty acid in callus, leaf and nodal segments with 35.0, 39.0 and 40.0% (w/w), of the lipid composition, respectively. With this paper, it is being reported for the first time the capacity of callus culture to accumulate fatty acids. Our results could serve to continue studying the production of fatty acids in callus cultivation as a biotechnological tool to improve different olive cultivars.

The effect of metals on the photosynthetic activities and epidermal polyphenol content of Prosopis glandulosa and Prosopis juliflora leaves was investigated by the tissue tolerance test. Foliar tissues of Prosopis glandulosa and Prosopis juliflora were incubated with Cd2+ (0.001 M) or Cu2+ (0.52 M) concentrations for 96 h. The results showed that significant reductions (p < 0.05) of photochemical efficiency in P. juliflora leaves were found after 96 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and controls. In contrast, P. glandulosa leaves showed a progressive increase on photochemical efficiency at 72 h after Cu-treatment. The results also showed a significant decrease (p < 0.05) of epidermal polyphenols in P. juliflora leaves after 24 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and control leaves. On the other hand, the values of leaf epidermal polyphenols observed in P. glandulosa exposed to copper and cadmium did not show any difference with respect to control. These findings are very important and suggest that these compounds could be considered as a protection mechanism of P. glandulosa when is treated with these heavy metals. Finally, the results of bioaccumulation showed that the copper concentration in P. glandulosa was higher than the values detected in P. juliflora Nevertheless, the cadmium concentration in foliar tissues of P. juliflora was significantly higher than P. glandulosa after 96 h of exposure to Cu2+ or Cd2+. Therefore, future studies are necessary to elucidate the effects of heavy metals on the biosynthesis of flavonoids and participation of these compounds in the reduction of metal toxicity in Prosopis species.

In vitro antiviral effect of a crude methanol extract and six fractions isolated from Rhoeo discolor against pandemic influenza A (H1N1) evaluated herein. The phytochemical analysis to identify the main classes of secondary metabolites was performed by thin layer chromatography (TLC). The cytotoxic effect and cell viability was determined in MDCK cells, and the antiviral activity was evaluated by qRT-PCR to detect influenza virus nucleoprotein (NP) gene. Finally a metabolomic analysis was performed using UPLC-MS. The phytochemical analysis revealed the presence of coumarins, tannins, saponins and flavonoids in the methanol extracts. Cytotoxicity related to 50% cell viability indicated concentrations of 1μg/mL for the crude extracts. Fraction MF1 inhibited synthesis of viral NP at co-treatment level at a concentration of 0.02 + 0.07 g/mL with a selectivity index (SI) of 32. The metabolomic analysis identified the presence of five flavonoids kaempferol, quercetin, isoquercetin luteolin-5-glucoside and rutin. Antiviral activity of flavonoids from R. discolor against the influenza AH1N1 virus are reported for the first time.

Factors such as slow growth, low rates of sexual and asexual reproduction, and viability of seeds among others limit the massive propagation of Agave americana L. by conventional methods. In this study, callus induction and shoot proliferation was determined in A. americana using Murashige and Skoog (MS) medium supplemented with dicholorophenoxyacetic acid (2,4-D) and 6-benzyl adenine (BA). Meristematic tissue was used as the explants, and were placed on MS medium supplemented with 30.0 g·L−1 sucrose with 0.11, 0.18, or 0.45 μm 2,4-D and 11.0, 22.0, 38.2, 44.0, 58.7, or 73.3 μm BA. Treatments were implemented according to factorial experimental design 3 × 6. After 1 month, the number of explants with callus was determined, whereas the numbers of shoots per explant were monitored after 4, 16, 20, and 36 weeks. The maximum percent of explants with callus was obtained with 0.11 μm 2,4-D and 58.7 and 73.3 μm BA, whereas the maximum numbers of shoots per explant (71) were obtained with 0.11 μm 2,4-D and 73.3 μm BA. The effect of different concentrations of indolebutyric acid (IBA) in the rooting of shoots was evaluated. There were no significant effects of IBA on the number of roots, root length, and axillary roots. Plantlets were acclimatized in the glasshouse and they did not show any phenotypic alteration. This is a highly efficient protocol for the in vitro propagation of A. americana via indirect organogenesis.

In the present study the characterization and properties of silver nanoparticles from Prosopis glandulosa leaf extract (AgNPs) were investigated using UV–Vis spectroscopic techniques, energy dispersive X-ray spectrometers (EDS), zeta potential and dynamic light scattering. The UV–Vis spectroscopic analysis showed the absorbance peaked at 487 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 421 nm with higher stability (−200 mV). The EDS analysis also exhibited presentation of silver element. Additionally, the different concentrations of AgNPs (25, 50, 75 and 100 mg/mL) showed antibacterial activity against Acinetobacter calcoaceticus and Bacillus cereus. Finally, AgNPs from leaf extracts of P. glandulosa may be used as an agent of biocontrol of microorganism of importance medical. However, further studies will be needed to fully understand the antimicrobial activity of silver nanoparticles obtain from P. gland...

The green iguana appears to be a reservoir for bacteria causing gastrointestinal infections in humans. The presence of diarrheogenicE. coli(DEC) pathotypes, however, has not been studied in this reptile. The aim of the current work was to investigate the prevalence of DEC in the intestines of 240 captive green iguanas, their phylogenetic groups, and the antibiotic susceptibility profile.E. colistrains were isolated from 41.7% of the intestinal content of green iguanas. DEC strains was identified in 25.9% of the screened population and were detected in the majority (62%, p=0.009] of those reptiles carryingE. colistrains. Among DEC strains, STEC strains carrying thestx1gene were the most prevalent pathotype isolated (38.7%), followed by EAEC and ETEC (27.4% each). Genetic markers of DEC strains belonging to the EHEC pathotype were not detected. More than a half of DEC strains were classified into the Clade I-II phylogroup (64.5%), followed by the phylogroup A (14.5%). The antibiotic susceptibility method demonstrated that a high proportion of DEC strains were resistance, or non-susceptible, to carbenicillin, amikacin, and ampicillin (85, 74, and 66%, respectively). We conclude that the green iguana kept in captivity is a reservoir of DEC strains bearing resistance to first-line antibiotics, including penicillins. Given the increase presence of the green iguana in Latin American households, these reptiles represent a potential source of transmission to susceptible humans and therefore a potential source of gastrointestinal disease.ImportanceLatin-American countries present a high burden of diarrheal disease. In this part of the world, besides common pathogens, diarrheal diseases are also caused by pathogenic types ofE. colireferred as “diarrheagenicE. coli” (DEC). While inhabitants of Latin American countries suffer of self-limiting diarrhea when infected with DEC, a main target of these strains are tourists from developed countries who are not exposed to DEC strains. Efforts are in place to decrease the burden of DEC-associated diarrheal disease. As such, this study investigated a potential reservoir of DEC strains that had been underestimated, the green iguana. These reptiles are very common in Latin American households and are found virtually everywhere in Mexico, Central and South America. We found that 25% of green iguanas carried DEC strains in their intestines. We also demonstrated a high prevalence of antibiotic resistance in these strains, posing a potential risk to humans.

Endosulfan lactone is a metabolite obtained from the biological oxidation of the insecticide endosulfan by action of the microorganisms present in the soil. This metabolite is more toxic and persistent than the parent compound. Therefore, it is extremely important to be able to determine the presence of this metabolite in the soil. However, accessible methods for extraction of endosulfan lactone in soil were not found in published literature. For this reason, the aim of this study was to evaluate two conventional methods of liquid–solid extraction for the determination of endosulfan lactone in solid substrate using two solvents (ethyl acetate and acetonitrile) and HPLC UV-VIS. The acetonitrile and rotary agitation extraction method was the one with the highest efficiency (97%), optimized using a factorial 32 response surface design, and validated in terms of linearity and precision. The linearity shown was r &gt, 0.999 in a wide spike level (0.15–100 mg kg−1), with the detection limit (DL) of 0.045 mg kg−1 and quantification limit (QL) of 0.15 mg kg−1. The extraction of endosulfan lactone in solid substrate using acetonitrile was more efficient than that used with ethyl acetate, so this method could be used to extract and quantify endosulfan lactone in agricultural soil.

The effect of plant growth-promoting bacteria inoculation on plant growth and the sugar content in Agave americana was assessed. The bacterial strains ACO-34A, ACO-40, and ACO-140, isolated from the A. americana rhizosphere, were selected for this study to evaluate their phenotypic and genotypic characteristics. The three bacterial strains were evaluated via plant inoculation assays, and Azospirillum brasilense Cd served as a control strain. Phylogenetic analysis based on the 16S rRNA gene showed that strains ACO-34A, ACO-40 and ACO-140 were Rhizobium daejeonense, Acinetobacter calcoaceticus and Pseudomonas mosselii, respectively. All of the strains were able to synthesize indole-3-acetic acid (IAA), solubilize phosphate, and had nitrogenase activity. Inoculation using the plant growth-promoting bacteria strains had a significant effect (p < 0.05) on plant growth and the sugar content of A. americana, showing that these native plant growth-promoting bacteria are a practical, simple, and efficient alternative to promote the growth of agave plants with proper biological characteristics for agroindustrial and biotechnological use and to increase the sugar content in this agave species.

Los protocolos actuales para la micropropagacion de Agave americana L. tienen limitaciones para su aplicacion comercial debido al bajo numero de plantas producidas por cada explante. La organogenesis indirecta podria ser una alternativa, sin embargo, es necesario optimizar los reguladores de crecimiento vegetal para maximizar el numero de plantas. El objetivo del trabajo fue optimizar la concentracion de acido 2,4-diclorofenoxiacetico (2,4-D) y de 6-bencil adenina (BA) sobre la induccion de callos embriogenicos en A. americana usando meristemos apicales como explante para maximizar el numero de brotes por callo, utilizando un diseno experimental de superficie de respuesta. Se utilizo el medio Murashige Skoog (MS) adicionado con 30 g l-1 de sacarosa, y con 0,11;0,18; 0,45 o 2,26 μM de 2,4-D, y 11,0; 22,0; 38,2 o 44,0 μM de BA. Se implementaron 9 tratamientos con 3 repeticiones y el numero de brotes por callo fue evaluado despues de 4, 16, 20 y 36 semanas. Se indujo el enraizamiento in vitro usando medio MS adicionado con acido indolbutirico (AIB). Se obtuvo un maximo de 74 plantulas por callo, usando 2,26 μM de 2,4-D y 38,2 μM de BA. En conclusion, la organogenesis indirecta podria ser una alternativa para la micropropagacion de A. americana L con fines comerciales.

In the present study the production of phenolic acids and flavonoid compounds by E. gracilis exposed to two cadmium concentrations (0.02 and 0.14 mM) was evaluated using high-performance liquid chromatography (HPLC). The results showed that E. gracilis exposed to 0.02 mM Cd+2 increased significantly the total content of phenolic compounds (798.46 ± 12.61 μg GA/g) and total flavonoids (241.34 ± 47.63 μg QE/g) with respect to the control (137.34 ± 19.80 μg QE/g DW and 549.00 ± 8.57 μg GA/g DW, respectively). However, no significant increase in the total content of phenolic compounds (568.54 ± 17.42 μg GA/g DW) and total flavonoids (141.11 ± 9.36 μg QE/g DW) were observed in E. gracilis exposed to 0.14 mM Cd+2. Further research is necessary to determine the specific role of flavonoids in E. gracilis exposed to high concentrations of Cd+2.