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1.
Biomed Chromatogr ; 34(1): e4705, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31629370

RESUMO

Lithocarpus polystachyus leaves exhibit antidiabetic activity and is consumed as a herbal tea in China. In this study, phytochemical profiles of L. polystachyus leaves were identified and characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight-MS in both positive and negative ion modes. A total of 17 compounds were tentatively characterized and identified by accurate mass and characteristic fragment ions. The total phenolic contents in the leaf extracts ranged from 9.0 to 13.4 g gallic acid equivalents/100 g of dry weight (DW). In addition, the effect of these extracts on inhibiting the activities of α-glucosidase and protein tyrosine phosphatase 1B (PTP1B) were evaluated. L. polystachyus extracts demonstrated significant inhibition of α-glucosidase (more than 88.1% at a concentration of 1.25 mg/mL) and acarbose (93.6% at a concentration of 5 mg/mL) while the PTP1B inhibition rate was over 84.3%. The antioxidant capacities of the leaf extracts were determined using 2,2-diphenyl-1-picrylhydrazyl, ABTS, and ferric reducing ability of plasma methods and ranged from 50.5 to 72.5 g trolox, from 43.2 to 77.7 g trolox, and from 5.0 to 10.6 g butylated hydroxytoluene (BHT; equaling trolox or BHT per 100 g of DW), respectively. Based on these results, L. polystachyus can be considered as a functional food owing to its antidiabetic and antioxidative activities, which are attributed to its rich phenolic and dihydrochalcone contents.


Assuntos
Fagaceae , Compostos Fitoquímicos , Extratos Vegetais , Antioxidantes , Cromatografia Líquida de Alta Pressão/métodos , Inibidores de Glicosídeo Hidrolases/química , Humanos , Espectrometria de Massas/métodos , Fenóis/análise , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores
2.
Mol Genet Genomics ; 295(1): 107-120, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31506717

RESUMO

The oriental gall wasp Dryocosmus kuriphilus represents a limiting pest for the European Chestnut (Castanea sativa, Fagaceae) as it creates severe yield losses. The European Chestnut is a deciduous tree, having major social, economic and environmental importance in Southern Europe, covering an area of 2.53 million hectares, including 75,000 ha devoted to fruit production. Cultivars show different susceptibility and very few are resistant to gall wasp. To deeply investigate the plant response and understand which factors can lead the plant to develop or not the gall, the study of transcriptome is basic (fundamental). To date, little transcriptomic information are available for C. sativa species. Hence, we present a de novo assembly of the chestnut transcriptome of the resistant Euro-Japanese hybrid 'Bouche de Bétizac' (BB) and the susceptible cultivar 'Madonna' (M), collecting RNA from buds at different stages of budburst. The two transcriptomes were assembled into 34,081 (BB) and 30,605 (M) unigenes, respectively. The former was used as a reference sequence for further characterization analyses, highlighting the presence of 1444 putative resistance gene analogs (RGAs) and about 1135 unigenes, as putative MiRNA targets. A global quantitative transcriptome profiling comparing the resistant and the susceptible cultivars, in the presence or not of the gall wasp, revealed some GO enrichments as "response to stimulus" (GO:0050896), and "developmental processes" (e.g., post-embryonic development, GO:0009791). Many up-regulated genes appeared to be transcription factors (e.g., RAV1, AP2/ERF, WRKY33) or protein regulators (e.g., RAPTOR1B) and storage proteins (e.g., LEA D29) involved in "post-embryonic development". Our analysis was able to provide a large amount of information, including 7k simple sequence repeat (SSR) and 335k single-nucleotide polymorphism (SNP)/INDEL markers, and generated the first reference unigene catalog for the European Chestnut. The transcriptome data for C. sativa will contribute to understand the genetic basis of the resistance to gall wasp and will provide useful information for next molecular genetic studies of this species and its relatives.


Assuntos
Fagaceae/genética , Transcriptoma/genética , Vespas/patogenicidade , Animais , Europa (Continente) , Fagaceae/parasitologia , Perfilação da Expressão Gênica/métodos , Repetições de Microssatélites/genética , Anotação de Sequência Molecular/métodos , Doenças das Plantas/parasitologia , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética , Árvores/genética , Árvores/parasitologia , Regulação para Cima/genética
3.
J Sci Food Agric ; 100(3): 1265-1273, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31709548

RESUMO

BACKGROUND: The aim of this work was to evaluate the effect on chemical composition, physico-chemical properties, cooking characteristics, fatty acid profile, lipid oxidation, and sensory acceptability of an oil-in-water emulsion gel that was prepared with chestnut flour, chia oil, gellan gum, and water (CEG), used as a fat replacer in pork burgers. The original mixture was used as a control sample (CS). The other samples were formulated partially replacing pork backfat with 5% of CEG (CEG5%) and 10% of CEG (CEG10%). RESULTS: Proximate analysis of samples showed several differences between samples. The CEG addition was found to be effective for improving the cooking yield while diameter reduction and thickness increase were positively affected. As regards lipid oxidation, in cooked burger, the 2-thiobarbituric acid (TBA) values for CS, CEG5% and CEG10% were 0.46, 0.57, and 0.59 mg malonaldehyde/kg sample, respectively. The linolenic and linolenic acid content of pork burger increased as CEG addition increased. Sensory properties for CS and CEG5% were similar whereas CEG10% showed the highest sensory scores. CONCLUSIONS: A combination of chestnut flour and chia oil could be used as a novel ingredient to develop pork burgers with a better nutritional profile without diminishing their sensory and physico-chemical properties. © 2019 Society of Chemical Industry.


Assuntos
Fagaceae/química , Substitutos da Gordura/análise , Farinha/análise , Produtos da Carne/análise , Óleos Vegetais/análise , Salvia/química , Animais , Culinária , Emulsões/química , Aditivos Alimentares/análise , Géis/química , Humanos , Suínos , Paladar
4.
Ecotoxicol Environ Saf ; 187: 109750, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655412

RESUMO

Drought and nitrogen (N) deposition are important components of global climate and environmental change. In this greenhouse study, we investigated the ecophysiological responses of the seedlings of three subtropical forest plant species (Schima superba, Castanopsis fissa, and Michelia macclurei) to short-term experimental drought stress, N addition, and their interaction. The results showed that drought stress reduced the activities of antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)] and total antioxidant capacity (T-AOC), but increased the malondialdehyde (MDA), abscisic acid (ABA), and proline (PRO) contents in plants. The PRO content, T-AOC, and antioxidant enzyme activities were increased, and ABA and MDA contents were decreased by N addition alone. Furthermore, N addition under drought stress increased antioxidant enzymes activities, PRO content, and T-AOC. The treatments, however, did not significantly affect the chlorophyll fluorescence parameters of the species. T-AOC was positively correlated with antioxidant enzyme activities in each species, indicating that antioxidant enzymes were important for plant resistance to oxidative stress. MDA content increased with the increase of ABA content, indicating that ABA may help regulate stomatal movement and drought-induced oxidative injury in plants. T-AOC was positively correlated with PRO content, probably because PRO participated in osmotic regulation of cells and increased osmotic stress resistance. These results indicate that N addition can reduce drought stress of subtropical forest plants and will help researchers predict how evergreen broad-leaved forests will respond to global change in the future.


Assuntos
Poluentes Atmosféricos/toxicidade , Antioxidantes/metabolismo , Secas , Compostos de Nitrogênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Árvores/efeitos dos fármacos , China , Monitoramento Ambiental , Fagaceae/efeitos dos fármacos , Fagaceae/metabolismo , Florestas , Osmose/efeitos dos fármacos , Pressão Osmótica/efeitos dos fármacos , Árvores/metabolismo , Clima Tropical
5.
Science ; 366(6467)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31727802

RESUMO

Denk et al agree that we reported the first fossil Fagaceae from the Southern Hemisphere. We appreciate their general enthusiasm for our findings, but we reject their critiques, which we find misleading and biased. The new fossils unequivocally belong to Castanopsis, and substantial evidence supports our Southern Route to Asia hypothesis.


Assuntos
Fagaceae , Floresta Úmida , Ásia , Fósseis
6.
Phytopathology ; 109(12): 2055-2063, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31411547

RESUMO

Intraspecific cryptic invasions may occur when new strains of an invasive species are introduced into an area where this species had already been introduced previously. In plant pathogens, such invasions are not well studied, even if, potentially, they can have severe consequences. Here, we investigated the effects of a potential intraspecific invasion in Europe of Cryphonectria parasitica, the causal agent of chestnut blight. Specifically, we tested the hypotheses that (i) non-European strains are more virulent on Castanea sativa than those already present in Europe because they have never encountered this new host, and (ii) the variation in virulence among strains is higher within native than within introduced populations. In a greenhouse, 2-year-old C. sativa seedlings were inoculated with Cryphonectria parasitica strains from South Korea, the United States, and Switzerland, and lesion development and seedling mortality were recorded weekly. Additionally, growth and sporulation of the strains were measured in vitro on agar medium at 15 and 24°C. Although lesion growth was similar for all strains, seedlings inoculated with strains from South Korea and Switzerland died faster than seedlings inoculated with strains from the United States. Moreover, in vitro strains from South Korea grew faster and produced more spores at both temperatures than the strains from the other two countries. In conclusion, our results did not support the two hypotheses. All strains, regardless of their origin, were found to be highly virulent on the inoculated chestnut seedlings. Nevertheless, current phytosanitary measures to avoid the introduction of new genotypes of C. parasitica into Europe should be further implemented.


Assuntos
Ascomicetos , Fagaceae , Ascomicetos/patogenicidade , Europa (Continente) , Fagaceae/microbiologia , Doenças das Plantas/microbiologia
7.
Exp Appl Acarol ; 79(1): 47-68, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31388896

RESUMO

We compared the life cycles and diapause attributes among three closely related spider mites, Oligonychus castaneae on Castanea crenata, and O. gotohi and O. amiensis on Lithocarpus edulis. The lower thermal thresholds from egg to egg were 10.5, 8.5 and 8.9 °C, respectively, and the thermal constants were 177.8, 229.5 and 232.5 degree-days, respectively. The cumulative hatching rates of diapause eggs of O. castaneae and O. gotohi increased as the season progressed in and after early-to-mid January, which indicates diapause termination. In contrast, O. amiensis showed higher hatching rates in December and January, but hatchability gradually decreased in and after February because some of the eggs died from the cold. Oligonychus castaneae and O. gotohi females produced diapause eggs in response to the short photoperiod in late September to early October and in early-to-late October, respectively, which corresponded to the times predicted by the critical photoperiods (at 15 °C) of 12 h 15 min and 11 h 15 min for the respective species. Oligonychus castaneae showed at least a single population peak over the 3-year observation period, but the time of peak population varied from mid-July to mid-September. The population of O. gotohi was higher between November and May when diapause eggs were present on host plants in early winter and the first-generation females laid eggs on leaves in spring. The population of O. amiensis, which is a non-diapause species, was only high between September and December, because eggs were laid on leaves in autumn to winter and then gradually disappeared and/or died during winter. Natural enemies were observed as the number of spider mites declined, and the density suppression effect by natural enemies was confirmed in the field.


Assuntos
Diapausa , Cadeia Alimentar , Fotoperíodo , Tetranychidae/fisiologia , Animais , Fagaceae , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Óvulo/crescimento & desenvolvimento , Dinâmica Populacional , Estações do Ano , Especificidade da Espécie , Tetranychidae/crescimento & desenvolvimento
8.
Molecules ; 24(14)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323897

RESUMO

Chestnut fruit abounds in carbohydrates, proteins, unsaturated fatty acids, fiber, polyphenolic compounds, as well as vitamins and micronutrients, that are behind the health-promoting properties of this plant. The purpose of the discussed research was to obtain innovative gluten-free pasta from rice and field bean flour enriched with a various addition of chestnut flour. Regarding the studied pasta, the following were determined: the content of free phenolic acids, total polyphenols, and antioxidant properties. Chromatographic analysis (HPLC-ESI-MS/MS (high-performance liquid chromatography-electrospray ionization tandem mass spectrometry)) revealed a wide variety of phenolic acids. In a sample with 20% and higher content of chestnut flour, as many as 13 acids were detected. Isoferulic acid prevailed. The total content of free phenolic acids and total polyphenols increased along with the increasing chestnut content. Moreover, in most cases, the content of individual acids increased with the addition of chestnut flour. Besides, the antioxidant activity was positively correlated with the addition of chestnut fruit flour, the content of free phenolic acids, and total polyphenols. Our research has demonstrated that our innovative gluten-free pasta, with the addition of chestnut flour, has a potential to be a source of polyphenolic compounds, including free phenolic acids, that are valuable for human health.


Assuntos
Antioxidantes/farmacologia , Dieta Livre de Glúten , Fagaceae/química , Farinha , Fenóis/farmacologia , Antioxidantes/química , Cromatografia Líquida , Farinha/análise , Espectrometria de Massas , Fenóis/química , Polifenóis/química , Polifenóis/farmacologia
9.
Int J Biol Macromol ; 137: 712-720, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279891

RESUMO

Large and small granules were separated from C-type starches of four Chinese chestnut varieties growing in the same environment. They had similar amylose contents from 17.7% to 20.2% and showed C-type crystallinity. The large granules had relative crystallinity from 19.2% to 20.3%, ordered degree from 0.672 to 0.706, and lamellar peak intensity from 233.2 to 267.1, but small granules had relative crystallinity from 16.2% to 18.2%, ordered degree from 0.635 to 0.663, and lamellar peak intensity from 201.6 to 213.1. The gelatinization peak temperatures ranged from 62.6 to 65.7 °C in large granules but from 60.3 to 61.7 °C in small granules, and enthalpy variation did from 12.5 to 13.7 J/g in large granules but from 10.1 to 11.7 J/g in small granules. Both large and small granules showed biphasic hydrolysis. Though small granules had significantly higher hydrolysis rate than large granules, but they had similar total hydrolysis extent during whole hydrolysis. The granule size had significantly positive relationships with relative crystallinity, ordered degree, lamellar peak intensity, and gelatinization temperature and enthalpy variation, but was negatively correlated to hydrolysis rate. The principal component analysis was conducted to reveal the interrelationships among different starch properties and the variations among different starches.


Assuntos
Fagaceae/química , Amido/química , Temperatura Ambiente , Amilose/análise , Hidrólise
10.
Science ; 364(6444)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31171664

RESUMO

The beech-oak family Fagaceae dominates forests from the northern temperate zone to tropical Asia and Malesia, where it reaches its southern limit. We report early Eocene infructescences of Castanopsis, a diverse and abundant fagaceous genus of Southeast Asia, and co-occurring leaves from the 52-million-year-old Laguna del Hunco flora of southern Argentina. The fossil assemblage notably includes many plant taxa that associate with Castanopsis today. The discovery reveals novel Gondwanan history in Fagaceae and the characteristic tree communities of Southeast Asian lower-montane rainforests. The living diaspora associations persisted through Cenozoic climate change and plate movements as the constituent lineages tracked post-Gondwanan mesic biomes over thousands of kilometers, underscoring their current vulnerability to rapid climate change and habitat loss.


Assuntos
Evolução Biológica , Fagaceae/classificação , Fósseis , Floresta Úmida , Argentina , Ásia , Chile , Mudança Climática , Folhas de Planta
11.
Food Chem ; 297: 124979, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253311

RESUMO

Oak honeydew and chestnut honeys often share the same production area in Atlantic landscapes. Consequently these honeys have common physicochemical properties and pollen composition, making their differentiation by routine methods, a difficult task. The increase in the demands of consumers for clear honey labelling, identifying floral make-ups and the substantial health properties of both honey types, make it necessary to improve methods to differentiate the honeys. Statistical multivariate techniques were used to study the differences in the physicochemical composition and pollen spectra between chestnut honey and oak honeydew honey. Palynological analysis, moisture, pH, electrical conductivity, hydroxymethylfurfural, diastase number, colour, phenolic content, minerals and sugars were used for this purpose. The variables that had more weight in the differentiation by principal component analysis were Castanea, Cytisus type, CIELab coordinates (a* and L), RSA, Mg and trehalose; 97.6% of the honey samples were correctly classified by linear discriminant analysis.


Assuntos
Fagaceae/química , Mel/classificação , Minerais/análise , Quercus/química , Açúcares/análise , Geografia , Mel/análise , Análise Multivariada , Pólen/química , Análise de Componente Principal
12.
J Sci Food Agric ; 99(13): 6060-6065, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31226223

RESUMO

BACKGROUND: Chestnuts are gluten-free, low-fat, cholesterol-free products. Postharvest decay reduces chestnut shelf life and can cause severe economic losses. In this study we investigated the effect of ozone (O3 ) gaseous treatment on chestnut rot caused by Gnomoniopsis castanea and the quality parameters of chestnuts. RESULTS: The results showed that ozone treatment (150 ppb during the day, and 300 ppb during the night) reduced the decay of chestnuts and had a fungistatic effect on isolates of G. castanea. The exposure of chestnuts to ozone did not alter weight losses, sugar content and titratable acidity. The concentration of total phenolics decreased during the storage period, both for treated and untreated nuts. However, after 150 days of treatment the polyphenol content of the chestnuts exposed to ozone was significantly higher than in control nuts. CONCLUSIONS: Our results suggested that ozone is an appropriate and economical tool to maximize the quality of chestnut shelf life, enabling it to be stored for long periods. © 2019 Society of Chemical Industry.


Assuntos
Fagaceae/química , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Nozes/química , Ozônio/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Carboidratos/química , Fagaceae/microbiologia , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/química , Armazenamento de Alimentos , Nozes/microbiologia , Ozônio/química , Fenóis/química , Controle de Qualidade
13.
Plant Biol (Stuttg) ; 21(5): 783-795, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31081234

RESUMO

Fagaceae can be found in tropical and temperate regions and contain species of major ecological and economic importance. In times of global climate change, tree populations need to adapt to rapidly changing environmental conditions. The predicted warmer and drier conditions will potentially result in locally maladapted populations. There is evidence that major genera of the Fagaceae are already negatively affected by climate change-related factors such as drought and associated biotic stressors. Therefore, knowledge of the mechanisms underlying adaptation is of great interest. In this review, we summarise current literature related to genetic adaptation to abiotic environmental conditions. We begin with an overview of genetic diversity in Fagaceae species and then summarise current knowledge related to drought stress tolerance, bud burst timing and frost tolerance in the Fagaceae. Finally, we discuss the role of hybridisation, epigenetics and phenotypic plasticity in adaptation.


Assuntos
Fagaceae/fisiologia , Adaptação Fisiológica/genética , Mudança Climática , Fagaceae/genética , Variação Genética , Estresse Fisiológico
14.
Mycorrhiza ; 29(4): 313-324, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129728

RESUMO

Restoration of the American chestnut (Castanea dentata) is underway using backcross breeding that confers chestnut blight disease resistance from Asian chestnuts (most often Castanea mollissima) to the susceptible host. Successful restoration will depend on blight resistance and performance of hybrid seedlings, which can be impacted by below-ground fungal communities. We compared fungal communities in roots and rhizospheres (rhizobiomes) of nursery-grown, 1-year-old chestnut seedlings from different genetic families of American chestnut, Chinese chestnut, and hybrids from backcross breeding generations as well as those present in the nursery soil. We specifically focused on the ectomycorrhizal (EcM) fungi that may facilitate host performance in the nursery and aid in seedling establishment after outplanting. Seedling rhizobiomes and nursery soil communities were distinct and seedlings recruited heterogeneous communities from shared nursery soil. The rhizobiomes included EcM fungi as well as endophytes, putative pathogens, and likely saprobes, but their relative proportions varied widely within and among the chestnut families. Notably, hybrid seedlings that hosted few EcM fungi hosted a large proportion of potential pathogens and endophytes, with possible consequences in outplanting success. Our data show that chestnut seedlings recruit divergent rhizobiomes and depart nurseries with communities that may facilitate or compromise the seedling performance in the field.


Assuntos
Fagaceae/microbiologia , Fungos/isolamento & purificação , Microbiota , Micorrizas/isolamento & purificação , Doenças das Plantas/imunologia , Biodiversidade , Resistência à Doença , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Fagaceae/genética , Fagaceae/imunologia , Fungos/classificação , Fungos/genética , Hibridização Genética , Micorrizas/classificação , Micorrizas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Microbiologia do Solo
15.
Virology ; 533: 99-107, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31146252

RESUMO

Field-collected US strain C18 of Cryphonectria parasitica, the chestnut blight fungus, was earlier reported to be infected by a double-stranded RNA virus, mycoreovirus 2 (MyRV2). Next-generation sequencing has revealed co-infection of C18 by a positive-strand RNA virus, hypovirus 4 (CHV4). The current molecular and genetic analyses showed interesting commensal interactions between the two viruses. CHV4 facilitated the stable infection and enhanced vertical transmission of MyRV2, which was readily lost during subculturing and showed reduced vertical transmission in single infections. Deletion of a key antiviral RNA silencing gene, dcl2, in isolate C18 increased stability of MyRV2 in single infections. The ability of CHV4 to facilitate stable infection with MyRV2 appears to be associated with the inhibitory effect of CHV4 on RNA silencing via compromising the induction of transcriptional up-regulation of dcl2. These results suggest that natural infection of isolate C18 by MyRV2 in the field was facilitated by CHV4 co-infection.


Assuntos
Ascomicetos/genética , Ascomicetos/virologia , Inativação Gênica , Doenças das Plantas/microbiologia , Vírus de RNA/fisiologia , Reoviridae/fisiologia , Ascomicetos/imunologia , Ascomicetos/fisiologia , Fagaceae/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/imunologia , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Reoviridae/genética , Reoviridae/isolamento & purificação
16.
Food Chem ; 294: 378-383, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126477

RESUMO

The quality of starchy foods is highly correlated with their amylose content. After boiling or roasting, the amylose content in cooked chestnut starch decreased to 16.6-26.8%, which was significantly lower than that of raw chestnut starch (26.6-28.1%). After cooking, the pasting temperature and peak time increased, while the breakdown, peak viscosity, final viscosity and setback of starches decreased. The amylose content showed a negative correlation with the pasting characteristics of the starch gel of cooked chestnut. The amylose content negatively affected the springiness and chewiness of starch gel, and positively correlated with its cohesiveness and stringiness. The freeze-thaw stability of starch from cooked chestnut was lower than that of raw chestnut. The amylose content was negatively correlated with freeze-thaw stability and positively correlated with the solubility of starch. The results demonstrated that amylose plays an important role in the pasting and gel texture properties of starch during cooking.


Assuntos
Amilose/química , Fagaceae/química , Amido/química , Amilose/metabolismo , Fagaceae/metabolismo , Congelamento , Géis/química , Nozes/química , Nozes/metabolismo , Solubilidade , Amido/metabolismo , Temperatura Ambiente , Viscosidade
17.
Waste Manag ; 87: 472-484, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31109548

RESUMO

Four kinds of waste from the industrial processing of chestnuts (Castanea sativa), namely leaves, pruned material and burrs from chestnut tree plus chestnut shells, were characterized to determine their content in polymers and thus their potential use in biorefinery processes. Results revealed that chestnut burrs have the highest polysaccharide content being the most promising for carrying out the subsequent stages of acid hydrolysis. Treatment with diluted sulfuric acid (prehydrolysis) allowed the solubilization of xylose, glucose and arabinose, but also some toxic compounds such as furan derivatives, aliphatic acids and phenolic constituents. Xylose, the main component released in the hemicellulosic hydrolyzates, was maximized by using a 3**(2-0) full factorial design combined with desirability function. At optimum conditions set at 130 °C and 3% (w/v) H2SO4, this value was 22.6 g L-1 xylose. Three concentrations of activated charcoal (1, 2.5 and 5% w/v) were evaluated to remove certain unwanted byproducts, and it was found that under the highest dosage, 95.27 ±â€¯0.03% of the color was removed with an almost total reduction of furan derivatives, making this liquor an appropriate basis for the development of suitable culture media for lactic acid bacteria. To validate this hypothesis three lactic acid bacteria, namely Lactobacillus plantarum, Lactobacillus pentosus and Lactococcus lactis were positively tested finding lactic acid yields of 0.89, 0.92 and 0.83 g/L·h respectively.


Assuntos
Fagaceae , Xilose , Hidrólise , Ácido Láctico , Polissacarídeos
18.
Plant Dis ; 103(7): 1631-1641, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31033400

RESUMO

Restoration of American chestnut (Castanea dentata) depends on combining resistance to both the chestnut blight fungus (Cryphonectria parasitica) and Phytophthora cinnamomi, which causes Phytophthora root rot, in a diverse population of C. dentata. Over a 14-year period (2004 to 2017), survival and root health of American chestnut backcross seedlings after inoculation with P. cinnamomi were compared among 28 BC3, 66 BC4, and 389 BC3F3 families that descended from two BC1 trees (Clapper and Graves) with different Chinese chestnut grandparents. The 5% most resistant Graves BC3F3 families survived P. cinnamomi infection at rates of 75 to 100% but had mean root health scores that were intermediate between resistant Chinese chestnut and susceptible American chestnut families. Within Graves BC3F3 families, seedling survival was greater than survival of Graves BC3 and BC4 families and was not genetically correlated with chestnut blight canker severity. Only low to intermediate resistance to P. cinnamomi was detected among backcross descendants from the Clapper tree. Results suggest that major-effect resistance alleles were inherited by descendants from the Graves tree, that intercrossing backcross trees enhances progeny resistance to P. cinnamomi, and that alleles for resistance to P. cinnamomi and C. parasitica are not linked. To combine resistance to both C. parasitica and P. cinnamomi, a diverse Graves backcross population will be screened for resistance to P. cinnamomi, survivors bred with trees selected for resistance to C. parasitica, and progeny selected for resistance to both pathogens will be intercrossed.


Assuntos
Ascomicetos , Cruzamento , Resistência à Doença , Fagaceae , Phytophthora , China , Resistência à Doença/genética , Fagaceae/microbiologia , Fagaceae/parasitologia , Phytophthora/fisiologia , Plântula , Árvores/microbiologia , Árvores/parasitologia , Estados Unidos
19.
Int J Mol Sci ; 20(7)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934840

RESUMO

Chestnut (Castanea mollissima) is a deciduous tree species with major economic and ecological value that is widely used in the study of floral development in woody plants due its monoecious and out-of-proportion characteristics. Squamosa promoter-binding protein-like (SPL) is a plant-specific transcription factor that plays an important role in floral development. In this study, a total of 18 SPL genes were identified in the chestnut genome, of which 10 SPL genes have complementary regions of CmmiR156. An analysis of the phylogenetic tree of the squamosa promoter-binding protein (SBP) domains of the SPL genes of Arabidopsis thaliana, Populus trichocarpa, and C. mollissima divided these SPL genes into eight groups. The evolutionary relationship between poplar and chestnut in the same group was similar. A structural analysis of the protein-coding regions (CDSs) showed that the domains have the main function of SBP domains and that other domains also play an important role in determining gene function. The expression patterns of CmmiR156 and CmSPLs in different floral organs of chestnut were analyzed by real-time quantitative PCR. Some CmSPLs with similar structural patterns showed similar expression patterns, indicating that the gene structures determine the synergy of the gene functions. The application of gibberellin (GA) and its inhibitor (Paclobutrazol, PP333) to chestnut trees revealed that these exert a significant effect on the number and length of the male and female chestnut flowers. GA treatment significantly increased CmmiR156 expression and thus significantly decreased the expression of its target gene, CmSPL6/CmSPL9/CmSPL16, during floral bud development. This finding indicates that GA might indirectly affect the expression of some of the SPL target genes through miR156. In addition, RNA ligase-mediated rapid amplification of the 5' cDNA ends (RLM-RACE) experiments revealed that CmmiR156 cleaves CmSPL9 and CmSPL16 at the 10th and 12th bases of the complementary region. These results laid an important foundation for further study of the biological function of CmSPLs in the floral development of C. mollissima.


Assuntos
Fagaceae/crescimento & desenvolvimento , Fagaceae/genética , Flores/crescimento & desenvolvimento , Flores/genética , Giberelinas/farmacologia , MicroRNAs/genética , Família Multigênica , Proteínas de Plantas/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , Fagaceae/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Inflorescência/efeitos dos fármacos , Inflorescência/genética , MicroRNAs/metabolismo , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Filogenia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Reprodutibilidade dos Testes
20.
Glob Chang Biol ; 25(6): 2030-2042, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30912234

RESUMO

Climate change is affecting the distribution of species and the functioning of ecosystems. For species that are slow growing and poorly dispersed, climate change can force a lag between the distributions of species and the geographic distributions of their climatic envelopes, exposing species to the risk of extinction. Climate also governs the resilience of species and ecosystems to disturbance, such as wildfire. Here we use species distribution modelling and palaeoecology to assess and test the impact of vegetation-climate disequilibrium on the resilience of an endangered fire-sensitive rainforest community to fires. First, we modelled the probability of occurrence of Athrotaxis spp. and Nothofagus gunnii rainforest in Tasmania (hereon "montane rainforest") as a function of climate. We then analysed three pollen and charcoal records spanning the last 7,500 cal year BP from within both high (n = 1) and low (n = 2) probability of occurrence areas. Our study indicates that climatic change between 3,000 and 4,000 cal year bp induced a disequilibrium between montane rainforests and climate that drove a loss of resilience of these communities. Current and future climate change are likely to shift the geographic distribution of the climatic envelopes of this plant community further, suggesting that current high-resilience locations will face a reduction in resilience. Coupled with the forecast of increasing fire activity in southern temperate regions, this heralds a significant threat to this and other slow growing, poorly dispersed and fire sensitive forest systems that are common in the southern mid to high latitudes.


Assuntos
Mudança Climática , Fogo , Floresta Úmida , Cupressaceae , Ecossistema , Fagaceae , Tasmânia
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