Variation of the chemical and biochemical responses to salinity during germination and early growth of seedlings of two populations of Agave durangensis Gentry

Agave durangensis (Asparagaceae) sustains a mescal industry in Mexico. The main reproductive strategy of the species is by seeds. The increased demand for agave-based beverages encourages producers to seek new cultivation areas. However, more than half of the territory of the country includes arid and semiarid zones, which are highly affected by salinity. The aim of the current study was to determine if salinity triggers different seed germination potential and variable biochemical and chemical responses in seedlings of two populations of A. durangensis, that might confer different tolerance to salinity. Seeds from each population were irrigated with four salinity treatments. Germination potential, as well as growth parameters and biochemical and chemical attributes of seedlings, were determined. Although with reduced germinability and germination speed, seeds of the two populations were able to germinate even under the strongest NaCl concentration (100 mM) evaluated. Effects in the growth parameters were registered; however, the seedlings of both populations survived throughout the experiments, increasing chlorophyll content and cell viability in most saline treatments. The enzymatic defense mechanism and the accumulation of proline were activated in a salt-dependent manner, which did not occur with the phenolic compounds; however, monomeric anthocyanin accumulation was outstanding under the two strongest NaCl concentrations evaluated. Important interpopulation differences were registered in each type of response, which were differently regulated under variable NaCl concentrations, some of them being more important than others under a particular saline condition. Seeds from the population Durango were more sensitive to salinity

Variation of the phenolic composition and a-glucosidase inhibition potential of seeds, soaked seeds, and sprouts of four wild forms and four varieties of common bean (Phaseolus vulgaris)

The determination of the changes in the composition of bioactive phenolic compounds of germinating seeds which accumulate high levels of these compounds could contribute to the understanding of the germination mechanism and the development of markers for the selection of plant genotypes. In the current study, the changes in the phenolic composition and a-glucosidase inhibition activity, taking place during the germination of four wild forms and four varieties of common bean (Phaseolus vulgaris L.) from Durango Mexico, were determined. A total of 66 phenolic compounds (19 phenolic acids, 18 isoflavones, 18 flavonol glycosides, 3 flavonol aglycones, 3 flavones, 2 dihydroflavonoids, 2 chalcones and one non-identified type) were found by HPLC-DAD, which were differentially accumulated by the seeds, 24 h-soaked seeds, and 4 day-sprouts of each genotype. The accumulation of the flavonol aglycones, myricetin, quercetin and kaempferol was distinctive of the wild seeds. Soaking not only caused leaching and degradation but also triggered the synthesis of new phenolic compounds whereas germination diversified the composition of isoflavones and flavonol glycosides. The seeds of all genotypes analyzed were important inhibitors of a-glucosidase, improving their potential after soaking and germination. The results suggested that the structure rather than the concentration of the flavonoids and phenolic acids determined the inhibitory potential of a-glucosidase of samples. The principal component analysis and cluster analysis revealed HPLC-DAD phenolic profiles as genotype-specific chemomarkers at any of the states (seeds, soaked seeds, and sprouts). The results have wide implications on agronomy and food quality

Effect of salinity on DNA methylation and antioxidant phenolic compounds of wild watercress (Rorippa nasturtium aquaticum)

Epigenetic changes are involved in plant responses to stress. Cytosine methylation is one of the most important epigenetic changes, regulating gene expression. In this paper, the MSAP (methylation-sensitive amplification polymorphism) method was used to find out how the watercress (Rorippa nasturtium aquaticum) genome changed in response to 0, 60, 80, and 100 mM NaCl and how that affected phenylalanine ammonium lyase (PAL) activity, phenolic content, and antioxidant capacity. The results showed an inverse correlation between methylation levels and PAL activity and the contents of total phenolics and flavonoids, indicating salt stress-induced reprogramming of the methylation pattern of watercress, which has a negative effect on the synthesis of phenolics. The results revealed a significant decrease in phenolic contents and antioxidant activity under low and moderate salinity compared to control and an increase under strong salinity compared to moderate salinity. The findings of this study contribute to our understanding of the reprogramming of DNA methylation under salinity and its effect on watercress phenolic metabolism

Los fenoles del polen del género Zea

The variability of the pollen phenol composition of 32 populations of Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis, and Zea luxurians from Mexico and Guatemala were analyzed. The phenol profiles were assessed by HPLC-DAD, and UPLC-TOF-MS. A total of 23 phenolics (four phenolic acids, 16 flavonols, and three dihydroflavonoids) were found. Quercetin glycosides (seven derivatives besides the quercetin aglycone itself) were the predominant compounds in the pollen of all analyzed species and subspecies. The major compound in all the samples, including the pollen of maize, was identified as quercetin-3,3’-O-diglucoside. The pollen of all the species and subspecies of Zea examined showed very similar patterns of accumulated phenols; however, variation in the minor compounds (phenolic acids and dihydroflavonoids) allowed to discern some inter- and intraspecific variations, although the split of Zea in the sectionsLuxuriantes and Zea was not clearly supported. The low level of variability of the pollen phenol profiles throughout the genus Zea supports the proposal that maize and some teosintes are conspecific groups, and indicates that the pollen phenol composition is highly conserved in the different taxa of Zea.Se analizó la variabilidad de la composición fenólica del polen de 32 poblaciones de Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis yZea luxurians de México y Guatemala. Los perfiles se obtuvieron por cromatografía líquida de alta presión con detector de arreglo de diodos (HPLC-DAD) y cromatografía líquida de ultra resolución acoplada a espectrómetro de masas de tiempo de vuelo (UPLC-TOF-MS). Se encontró un total de 23 compuestos fenólicos (cuatro ácidos fenólicos, 16 flavonoles y tres dihidroflavonoides). Los derivados glicósidos de quercetina (siete derivados, además de la quercetina aglicona misma) fueron las substancias predominantes en todos los analisis realizados. El compuesto principal, el más abundante y presente en la totalidad de las muestras, incluido el maíz, se identificó como quercetina-3,3’-O-diglucósido. El polen de todas las especies y subespecies de Zea analizadas mostraron patrones muy similares de fenoles acumulados; sin embargo, diferencias en los compuestos menores (ácidos fenólicos y dihidroflavonoides) permitieron discernir variaciones inter e intraespecíficas, aunque la división del género en las dos secciones Luxuriantes y Zea no fue claramente sustentada. La baja variación de los perfiles fenólicos del polen dentro del género Zea apoya la propuesta de que el maíz y algunos teocintles son grupos conespecíficos, e indica que la composición fenólica del polen fue altamente conservada en los diferentes taxa de Zea a lo largo del tiempo

FENOLES DEL POLEN DE STENOCACTUS, ECHINOCEREUSY MAMMILLARIA(CACTACEAE)

A variable number of phenolics have beendetected in pollen of the following speciesof Cactaceae: Stenocactus multicostatussubsp. zacatecasensis, Echinocereusenneacanthus, Echinocereus pectinatus,Echinocereus triglochidiatus var.coccineus and Mammillaria heyderi sensulato. The phenolics were characterized by means of chromatographic (HPLC) andspectrometric (UV) properties. The mostabundant flavonols were 3-O-glycosidederivatives of kaempferol and 3-Oglycoside derivatives of quercetin. 3-Oglycoside derivatives of herbacetin werefound in lower abundance. Each species hada particular pollen phenolic profile.Intrapopulation variability in phenolicprofiles was detected in all cases. Thephenolic composition of these species isreported for the first time.Un número variable de compuestosfenólicos ha sido detectado en el polen deStenocactus multicostatus subsp.zacatecasensis (Britton et Rose) U. Guzmánet Vázquez-Benítez, comb. et stat. nov.,Echinocereus enneacanthus Engelm.,Echinocereus pectinatus (Scheidw.)Engelm., Echinocereus triglochidiatus var.coccineus (Engelm.) U. Guzmán, comb. etstat. nov. y Mammillaria heyderi sensulato, todas de la familia Cactaceae. Loscompuestos fenólicos fueron caracterizados por sus propiedades cromatográficas (HPLC) y espectrométricas (UV).Los fenoles encontrados fueron derivadosde ácidos fenólicos y flavonoides. Estosúltimos estuvieron representados porflavonoles, de éstos los más abundantesfueron los 3-O-glicósidos derivados decanferol y quercetina. En menor abundancia se encontraron derivados 3-O-glicósidos deherbacetina. Variabilidad intrapoblacionalen la composición fenólica del polen fueregistrada en todos los casos. Cada unode los taxa presentó un perfil fenólicoparticular. La composición de fenoles delpolen de estas especies es presentada porprimera vez

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

VALOR TAXONOMICO DE LOS PERFILES FENOLICOS DEL POLEN DE ALGUNAS ESPECIES DE LA FAMILIA CACTACEAE

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