Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.865
Filtrar
1.
Gene ; 758: 144950, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32683078

RESUMO

Sunflower (Helianthus annuus L.) is an important oil crop, the secondary metabolites of it include many compounds such as flavonoids and lignin. However, the research on the biosynthesis of phenolic compounds in sunflowers is still scarce. Cinnamate 4-hydroxylase (C4H) belongs to the cytochrome P450-dependent monooxygenase family and is involved in the synthesis of many phenolic compounds, but C4H in sunflowers has not yet been cloned and functionally characterized. In this study, we screened three C4H genes from the sunflower transcriptome and genomic databases, named HaC4H1, HaC4H2, and, HaC4H3, respectively. In heterologous expression experiments, we had improved a method from previous studies by the addition of restriction sites to make it easier to express multiple C4H functions and suitable for in vitro activity verification. HaC4Hs without the N-terminal membrane anchor region was fused with a redox partner of Arabidopsis thaliana cytochrome P450 enzyme (CYP450) by the method and functionally expressed in E. coli and the results showed that these three enzymes catalyzed the formation of p-coumaric acid. To further investigate whether our fusion protein approach is applicable to other C4Hs, we used this method to explore the functions of C4H from Peucedanum praeruptorum and Angelica decursiva, and they can also convert trans-cinnamic acid to p-coumaric acid. The gene expression profile showed that all three HaC4H genes showed the highest transcription levels in the roots and might be up-regulated by MeJA. In summary, these results reveal the function of HaC4Hs in sunflower and provide a simpler way to explore C4H and even other cytochrome P450 enzymes in prokaryotic expression systems.


Assuntos
Helianthus/enzimologia , Propionatos/metabolismo , Transcinamato 4-Mono-Oxigenase/genética , Transcinamato 4-Mono-Oxigenase/metabolismo , Sequência de Aminoácidos , Angelica/genética , Apiaceae/genética , Arabidopsis/genética , Clonagem Molecular , Proteínas Recombinantes de Fusão/genética , Alinhamento de Sequência , Transcriptoma/genética
2.
Chemosphere ; 258: 127386, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32559495

RESUMO

Contamination of agricultural land with heavy metal is a serious biological and environmental issue. Such threat can be challenged by exploring the plant symbiotic microbes that can improve plant growth through phyto-hormones secretion and chromate chelation. In the current study, chromate resistant rhizospheric Staphylococcus arlettae strain MT4 was isolated from the rhizosphere of Malvestrum tricuspadatum L. The strain showed potential to secrete phytohormones and plant growth promoting secondary metabolites under induced chromate stress, making it a best suitable candidate in chromate stress alleviation. Moreover, the rhizobacterium MT4 significantly promoted the net assimilation and relative growth rate of sunflower grown in the presence of chromate (100 ppm). Chromate stress alleviation strategy of MT4 strain was three-fold. MT4 alleviated chromate stress and promoted the sunflower growth by suppressing the chromate intake by the host, modulating phytohormones and strengthening of the host's antioxidant system. The improved antioxidant system was confirmed by noticing lower ROS accumulation and improved ROS scavenging, lower peroxidase activity and higher accumulation of phenols and flavonoids.


Assuntos
Antioxidantes/metabolismo , Cromatos/toxicidade , Helianthus/efeitos dos fármacos , Reguladores de Crescimento de Planta/metabolismo , Rizosfera , Poluentes do Solo/toxicidade , Staphylococcus/crescimento & desenvolvimento , Biodegradação Ambiental , Cromatos/metabolismo , Helianthus/metabolismo , Helianthus/microbiologia , Oxirredução , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Poluentes do Solo/metabolismo , Staphylococcus/metabolismo
3.
PLoS One ; 15(6): e0235415, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598354

RESUMO

To better understand the mechanism of inherent salt resistance in Jerusalem artichoke (Helianthus tuberosus L.), physiological and metabolic responses of tubers at the initiation stage of sprouting under different salt stress levels were evaluated in the present study. As a result, 28 metabolites were identified using proton nuclear magnetic resonance (1H-NMR) spectroscopy. Jerusalem artichoke tubers showed minor changes in metabolic response under moderate salt stress when they had not yet sprouted, where metabolism was downregulated at the start of sprouting and then upregulated significantly after plants became autotrophic. However, mild and severe salt stress levels caused different metabolic response patterns. In addition, the accumulation of fructose and sucrose was enhanced by moderate salt stress, while glucose was highly consumed. Aspartate and asparagine showed accelerated accumulation in sprouting Jerusalem artichoke tubers that became autotrophic, suggesting the enhancement of photosynthesis by moderate salt stress.


Assuntos
Frutose/metabolismo , Glucose/metabolismo , Helianthus/metabolismo , Tubérculos/metabolismo , Estresse Salino , Sacarose/metabolismo , Helianthus/crescimento & desenvolvimento , Fotossíntese , Tubérculos/crescimento & desenvolvimento
4.
Sci Total Environ ; 740: 140003, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32559533

RESUMO

Produced water (PW), a wastewater resulting from hydraulic fracturing and oil and gas production, has been utilized in arid regions for irrigation purposes and potentially presents a new water source for crop irrigation in areas of increasing water scarcity. However, there is a potential for both synthetic and geogenic contaminants in these waters to accumulate in irrigated food crops. This study assessed how water treatment technologies targeted at removal of salinity (i.e., total dissolved solids) and organic chemical content (i.e., dissolved organic carbon) from PW to achieve agricultural irrigation standards altered the impact of inorganic contaminants and nutrient uptake on two salt-tolerant food crops, sunflower (Helianthus annuus) and wheat (Triticum aestivum). The impacts of the treatment technologies on inorganic contaminant loadings in the irrigated soils were also assessed. Treatment technologies to improve PW quality decreased the adverse impacts on plant health; however, plant health was more affected by dilutions of PW than by the treatment technologies employed. Phenotypically, plants irrigated with 90% dilution (low) treatment groups, regardless of treatment technology, were comparable to controls; however, plants watered with high proportions (50%) of raw or treated PW displayed stunted growth, with reduced height and leaf area, and sunflower seed saw 100% yield loss. Although phenotypically similar, plants of the low treatment groups exhibited changes in the ionome, illustrating the influence of PW on plant uptake, translocation, and accumulation of metals, salts, and micronutrients. In addition, bioavailability of metals and nutrients was impacted by the unique and complex PW matrix: bioconcentration factors traditionally used to evaluate risk may therefore over or underestimate accumulation.


Assuntos
Helianthus , Purificação da Água , Irrigação Agrícola , Metais , Solo , Triticum , Águas Residuárias
5.
Phytochemistry ; 177: 112430, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32516579

RESUMO

Despite intensive research in recent years, the biosynthetic route to costunolide in sunflower so far remained obscured. Additional P450 sequences from public sunflower transcriptomic database were screened to search for candidate enzymes which are able to introduce the 6α-hydroxy-group required for the esterification with the carboxy group of germacarane A acid, the final step in costunolide formation. CYP71BL9, a new P450 enzyme from sunflower was shown to catalyze this hydroxylation, hence being identified as HaCOS. Phylogentically, HaCOS is closer related to HaG8H than to any other known costunolide synthase in Asteraceae.The enzyme was successfully employed to reconstruct the sunflower biosynthesis of costunolide in transformed tobacco. Contrary, in yeast, only minor amounts of sesquiterpene lactone was produced, while 5-hydroxyfarnesylic acid was formed instead. HaCOS in combination with HaG8H produced 8ß-hydroxycostunolide (eupatolide) in transformed plants, thus indicating that sunflower possesses two independent modes of eupatolide synthesis via HaCOS and via HaES. The lack of HaCOS expression and of costunolide in trichomes suggests that the enzyme triggers the costunolied synthesis of the inner tissues of sunflower and might be linked to growth regulation processes.


Assuntos
Helianthus , Sesquiterpenos , Lactonas , Tricomas
6.
Ying Yong Sheng Tai Xue Bao ; 31(2): 508-514, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476344

RESUMO

The effects of root abscisic acid (ABA) signal on Na+ transport and photosystem 2 (PS2) in Jerusalem artichoke (Helianthus tuberosus) under salt stress (150 mmol·L-1 NaCl) were examined by applying ABA synthesis inhibitor sodium tungstate to roots. Sodium tungstate inhibited ABA synthesis in roots, reduced root Na+ efflux, and increased the efficiency of Na+ transport from roots to leaves under salt stress. Salt stress increased leaf Na+ content and did not affect leaf membrane lipid peroxidation, PS2 reaction center protein and PS2 maximum photochemical efficiency (Fv/Fm ). The inhibition on root ABA synthesis significantly increased leaf Na+ accumulation, aggravated leaf membrane lipid peroxidation, impaired PS2 reaction center protein, decreased Fv/Fm, and induced PS2 photoinhibition. In conclusion, root ABA signal was beneficial to reducing leaf Na+ accumulation and preventing PS2 oxidative damage by inducing root Na+ efflux and inhibiting Na+ transport to the aerial part in H. tuberosus under salt stress.


Assuntos
Ácido Abscísico , Helianthus , Complexo de Proteína do Fotossistema II , Folhas de Planta , Raízes de Plantas , Estresse Salino
7.
Environ Sci Pollut Res Int ; 27(24): 29954-29966, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32445141

RESUMO

Soil pollution is rapidly increasing due to industrialization and urbanization. Heavy metal pollution raised concern because of its possible impact on plants and humans. Helianthus annuus L. is a good hyperaccumulator plant, used for the removal of heavy metals because of its phytoremediation efficiency. In the present study, we cultivated H. annuus plants in industrial contaminated soil collected from various industries like plastic, paper, dye, and textile of different areas of Jaipur (Rajasthan), Kashipur, Jaspur, and Bajpur (Uttrakhand), India. Plantlets accumulated a different range of Pb, Cd, Zn, Cu, Fe, and As (0.62-158.29, 0.8-59.6, 0.81-166.5, 0.09-101.89, 2.06-53.25, and 0.002-2.55 mg kg-1, respectively) from the industrial soil samples. Heavy metal analysis was done using flame and graphite furnace atomic absorption spectrophotometer. The effects of heavy metals were analyzed by studying the morphological, biochemical, and antioxidant enzymatic analysis. The results revealed that industrial contaminated soil had a significant impeding effect on the plantlets of H. annuus as noticed by the reduction in growth parameters compared to the standard. Furthermore, one-way ANOVA and principal component analysis (PCA) were applied for statistical analysis and to determine the correlation between plant growth parameters, removed heavy metals, and biochemical. Thus, this study will be helpful for the decontamination of highly affected industrial soil.


Assuntos
Helianthus , Metais Pesados/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Humanos , Índia , Solo
8.
J Anim Sci ; 98(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32277699

RESUMO

Leptin genotypes can be identified as homozygous normal (CC), homozygous mutant (TT), and heterozygous (CT) based on a single-nucleotide polymorphism in exon 2 of the leptin gene, which has been associated with feed intake and fat deposition in cattle. The experiment was designed as 2 × 2 × 2 factorial with three main factors: (1) genotype (CT or TT) and diets fed 2) with or without triticale dried distiller's grains with solubles (DDG), and 3) with either flaxseed (FS) or high-oleate sunflower seed (SS). Evaluations included growth performance, subcutaneous fat deposition, adipocyte cellularity, meat quality, and fatty acid (FA) profile of various depots. Beef steers (n = 40, 459 ± 31 kg) of either CT or TT genotypes were housed in individual pens with ad libitum access to one of the four diets: 75% steam-rolled barley + 10% barley silage with 10% FS or SS (non-DDG diets, NDG) and 46.5% barley + 10% barley silage + 30% DDG, with 8.5% FS or SS, all on a dry matter basis. Growth performance, ultrasound subcutaneous fat thickness, rib eye area (REA), and plasma FA were measured prior to and during the finishing period. At slaughter, samples of subcutaneous fat, perirenal fat, and Longissimus thoracis (LT) muscle were collected for FA analysis and carcass and meat quality were measured. Compared with CT cattle, TT tended to have less (P = 0.06) C18:2-c9,t11 (rumenic acid) in plasma and subcutaneous fat and a greater proportion (P < 0.05) of C18:0 in subcutaneous, perirenal, and LT fat. Cattle with TT genotype also tended (P < 0.1) to have more total saturated and less unsaturated (USFA) and monounsaturated fats (MUFA) and had less (P = 0.04) linoleic acid in LT. Ultrasound fat thickness, REA, and average diameter of adipocytes in subcutaneous fat at 12 wk were not affected (P > 0.39) by genotype. Generally, carcass and meat quality were similar (P > 0.1) among diets, although adding FS tended to increase (P = 0.06) total USFA of subcutaneous fat including omega-3 FA (P < 0.001). For the high-fat diets evaluated, CT cattle would have more potential to produce beef with enhanced health benefits than would TT cattle.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Ácidos Graxos/análise , Leptina/genética , Carne Vermelha/normas , Adipócitos/metabolismo , Animais , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Linho , Genótipo , Helianthus , Hordeum , Masculino , Ácido Oleico/análise , Sementes , Silagem/análise , Gordura Subcutânea/química , Triticale
9.
Mycorrhiza ; 30(2-3): 373-387, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32227272

RESUMO

Arbuscular mycorrhizal fungi (AMF) play a fundamental role in plant growth and nutrition in natural and agricultural ecosystems. Despite the importance of such symbionts, the different developmental changes occurring during the AMF life cycle have not been fully elucidated at the molecular level. Here, the RNA-seq approach was used to investigate Rhizoglomus irregulare specific and common transcripts at two different time points of mycorrhizal establishment in Helianthus annuus in vivo. Four days after inoculation, transcripts related to cellular remodeling (actin and tubulin), cellular signaling (calmodulin, serine/threonine protein kinase, 14-3-3 protein, and calcium transporting ATPase), lipid metabolism (fatty acid desaturation, steroid hormone, and glycerophospholipid biosynthesis), and biosynthetic processes were detected. In addition to such transcripts, 16 days after inoculation, expressed genes linked to binding and catalytic activities; ion (K+, Ca2+, Fe2+, Zn2+, Mn2+, Pi, ammonia), sugar, and lipid transport; and those involved in vacuolar polyphosphate accumulation were found. Knowledge of transcriptomic changes required for symbiosis establishment and performance is of great importance to understand the functional role of AMF symbionts in food crop nutrition and health, and in plant diversity in natural ecosystems.


Assuntos
Glomeromycota , Helianthus , Micorrizas , Ecossistema , Raízes de Plantas , RNA-Seq , Simbiose
10.
Sci Total Environ ; 724: 138259, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32247981

RESUMO

The improvement and development of saline-alkali soils is currently a hot economic and scientific issue, and exploring the correlation between rhizosphere microorganisms of plants growing on saline-alkali soils and their salt tolerance has become the key point of related research. In our study, the community structure of microorganism and various properties of saline soils were characterized in which Jerusalem artichoke grown along a soil salinity gradient. A variety of basic soil properties were measured and the amplicon was performed as well as metagenomic sequencing on coastal saline soils using various techniques (such as RDA analysis and the assembly of genomes) to evaluate microbial functions. In addition, WGCNA (Weighted gene coexpression network analysis) method was used to identify the species related to salt stress and the sequence binning to assemble two enriched putative bacterial genomes. The research showed the cultivation of Jerusalem artichoke on saline soil changed soil physico-chemical and enzymatic properties; most of the rapidly changing as well as the long-term stable properties differed significantly between the rhizosphere and bulk soils. The amplicon and metagenomic sequencing revealed the function and structure of microorganisms varied between the rhizosphere and bulk soils, with greater microbial diversity in the rhizosphere. Catalase activity and the moisture content were the factors with the greatest impact on microorganisms. The putative genomes of two species of microorganisms (belong to Nitrospira and Gemmatimonas) were assembled, identified microbial species that were highly responsive to salt stress and that may play a key role in saline soil, stressed the important role of archaea in microbial communities in response to salt stress. The study provides a comprehensive understanding of the microbial community structure in the rhizosphere of Jerusalem artichoke to enable the improvement and economic development of saline land.


Assuntos
Helianthus , Microbiota , Rizosfera , Solo , Microbiologia do Solo
11.
Plant Physiol Biochem ; 150: 254-262, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171164

RESUMO

Iron (Fe)-deficiency causes chlorosis and growth inhibition in sunflower, an important commercial crop. This study examines whether and how arbuscular mycorrhizal fungi (AMF) ameliorate Fe-deficiency symptoms in Fe-deficiency sensitive sunflower plants. AMF supplementation showed a significant improvement in plant biomass, chlorophyll score, Fv/Fm (quantum efficiency of photosystem II), and Pi_ABS (photosynthesis performance index), suggesting its beneficial effect under Fe deficiency. This AM-driven amelioration of Fe deficiency was further supported by the improvement of biochemical stress indicators, such as cell death, electrolyte leakage, superoxide anion, and hydrogen peroxide. In this study, the AMF supplementations resulted in significant improvement in Fe as well as Zn concentrations in root and shoot of sunflower under Fe deficiency. One of the primary Strategy-I responses, ferric reductase activity along with the expression of its respective gene (HaFRO1), significantly increased in roots due to AMF ensuring Fe availability in the rhizosphere under Fe deficiency. Our qPCR analysis also showed a significant upregulation of HaIRT1, HaNramp1, and HaZIP1 in roots of sunflower in the presence of AMF, suggesting that Fe and Zn transporters are concurrently involved with AMF-mediated alleviation of Fe deficiency. Further, AMF accelerates the activities of CAT and SOD, predominantly in roots to protect sunflower plants from Fe-deficiency reactive oxygen species (ROS). This study unveils the mechanistic basis of AMF to limit Fe deficiency retardation in sunflower.


Assuntos
Helianthus , Micorrizas , Eletrólitos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Helianthus/metabolismo , Helianthus/microbiologia , Ferro/deficiência , Micorrizas/fisiologia , Oxirredutases/metabolismo
12.
Food Chem ; 320: 126631, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222660

RESUMO

Effect of superfine grinding on pectin extraction was investigated. Sunflower heads were grinded into microparticles of ~50 µm, thus pectin chains were fully exposed due to cell wall breakdown. A good pectin yield of 14.5 ± 0.36% (w/w) was subsequently achieved at mild conditions (pH 5.0, 25 °C, 2 h) associated with 0.8% (w/v) sodium citrate (SC). However, the molecule weight of pectin was greatly reduced (Mw = 7.87 ± 0.21 kDa) due to the action of endo-pectinases. With heating (pH 5.0, 85 °C for 20 min, 25 °C for 1.5 h) the endo-pectinases were effectively inhibited, thus Mw was increased to 338.07 ± 12.37 kDa. With superfine grinding, pectin extracted with different conditions presented various properties. Pectin extracted at pH 2.5 had higher esterification degree (DE, ~40%) and gelled at 3% (w/v) concentration. In contrast, pectin extracted under mild condition with low DE (21%) cannot gel at the same concentration. Conclusively, superfine grinding has potential application in pectin extraction.


Assuntos
Helianthus/química , Pectinas/química , Esterificação , Temperatura Alta , Peso Molecular , Pectinas/isolamento & purificação
13.
Plant Mol Biol ; 103(4-5): 373-389, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166486

RESUMO

KEY MESSAGE: Even a point mutation in the psaA gene mediates chlorophyll deficiency. The role of the plastid signal may perform the redox state of the compounds on the acceptor-side of PSI. Two extranuclear variegated mutants of sunflower, Var1 and Var33, were investigated. The yellow sectors of both mutants were characterized by an extremely low chlorophyll and carotenoid content, as well as poorly developed, unstacked thylakoid membranes. A full-genome sequencing of the cpDNA revealed mutations in the psaA gene in both Var1 and Var33. The cpDNA from the yellow sectors of Var1 differs from those in the wild type by only a single, non-synonymous substitution (Gly734Glu) in the psaA gene, which encodes a subunit of photosystem (PS) I. In the cpDNA from the yellow sectors of Var33, the single-nucleotide insertion in the psaA gene was revealed, leading to frameshift at the 580 amino acid position. Analysis of the photosynthetic electron transport demonstrated an inhibition of the PSI and PSII activities in the yellow tissues of the mutant plants. It has been suggested that mutations in the psaA gene of both Var1 and Var33 led to the disruption of PSI. Due to the non-functional PSI, photosynthetic electron transport is blocked, which, in turn, leads to photodamage of PSII. These data are confirmed by immunoblotting analysis, which showed a significant reduction in PsbA in the yellow leaf sectors, but not PsaA. The expression of chloroplast and nuclear genes encoding the PSI subunits (psaA, psaB, and PSAN), the PSII subunits (psbA, psbB, and PSBW), the antenna proteins (LHCA1, LHCB1, and LHCB4), the ribulose 1.5-bisphosphate carboxylase subunits (rbcL and RbcS), and enzymes of chlorophyll biosynthesis were down-regulated in the yellow leaf tissue. The extremely reduced transcriptional activity of the two protochlorophyllide oxidoreductase (POR) genes involved in chlorophyll biosynthesis is noteworthy. The disruption of NADPH synthesis, due to the non-functional PSI, probably led to a significant reduction in NADPH-protochlorophyllide oxidoreductase in the yellow sectors of Var1 and Var33. A dramatic decrease in chlorophyllide was shown in the yellow sectors. A reduction in NADPH-protochlorophyllide oxidoreductase, along with photodegradation, has been suggested as a result of chlorophyll deficiency.


Assuntos
Apoproteína(a)/genética , Clorofila A/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Helianthus/genética , Complexo de Proteína do Fotossistema I/metabolismo , Mutação Puntual , Clorofila A/química , DNA de Plantas , Genoma de Planta , Fenótipo , Complexo de Proteína do Fotossistema I/genética , Pigmentação
14.
Food Chem ; 319: 126563, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32172048

RESUMO

Enzymatic hydrolysis of proteins produces bioactive peptides that have the potential to provide health benefits. This study examined the inflammatory- and immune-modulating properties of a flavourzyme-derived sunflower protein hydrolysate (SPH) and peptides. The SPH was fractionated into <1, 1-3, 3-5, and >5 kDa peptides by membrane ultrafiltration. The SPH blunted IL-1ß stimulated NFκB activation and boosted IL-4/GM-CSF induced expression of surface markers CD14 and CD86, indicating maturation into a dendritic cell (DC) phenotype. Testing of SPH membrane ultrafiltration and HPLC fractions indicated that smaller and non-polar peptides were the most potent, respectively. Four novel peptides (YFVP, SGRDP, MVWGP and TGSYTEGWS) were identified and all of them blunted IL-1ß stimulated NFκB activation. The peptides also boosted IL-4/GM-CSF induction of CD14, while only MVWGP and TGSYTEGWS boosted the expression of CD86. MVWGP was the most potent immune-modulatory peptide across all cellular assays, which was attributed to the presence of a methionine residue.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Helianthus/metabolismo , Monócitos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Peptídeos/farmacologia , Hidrolisados de Proteína/farmacologia , Linhagem Celular Tumoral , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Humanos , Monócitos/citologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Peptídeos/metabolismo , Hidrolisados de Proteína/metabolismo
15.
Food Chem ; 318: 126476, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32143132

RESUMO

A pilot-scale extraction of sunflower pectin with 0.74% (w/v) sodium citrate (72 °C, 194 min) and different procedures of purification including alcohol precipitation, ultrafiltration (UFDF) and microfiltration (MFDF) with diafiltration were carried out. Considering the alcohol treatment, the yields were similar at laboratory and pilot-scale (~8.9%), demonstrating the efficiency of the scale-up. With respect to membrane processes, the best results were obtained with UFDF, showing the highest yield (13.3%) and pectin concentration higher than 90%. In all cases, pectins presented very low amount (~1%) of glucose and mannose, monosaccharides not included in the pectin structure. Detailed NMR analysis and functional properties (emulsifying and viscosity) that were also assessed corroborated the good quality of UFDF obtained pectin. These results point out that the obtainment of sunflower pectin of good quality can be achieved at pilot-scale by the extraction with sodium citrate and purification with membrane separation, eco-friendly alternatives to conventional procedures.


Assuntos
Helianthus/química , Pectinas/química , Pectinas/isolamento & purificação , Fracionamento Químico , Emulsificantes/química , Citrato de Sódio/química , Ultrafiltração/métodos , Viscosidade
16.
Arch Microbiol ; 202(6): 1459-1467, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32189017

RESUMO

Sunflower is one of the most economically important oil crops. Recently, sunflower anthracnose caused by Colletotrichum destructivum was reported and suggested to be a potential threat to the quality of oil and edible seeds derived from sunflower in the field and even on the ornamentals in the residential gardens. Colletotrichum destructivum, as the causal agent of sunflower anthracnose, has been rarely studied. In this study, the vegetative growth and sporulation of this fungal species were investigated by assessing the requirements of nutrition and other environmental conditions, such as temperature, ambient pH, and lightness regime. Additionally, the sensitivity of C. destructivum to several fungicides was assessed. The results will provide a baseline for better understanding of the biology and etiology of C. destructivum. This study will be the first reference for a sustainable management strategy according to the occurrence and prevalence of the sunflower anthracnose.


Assuntos
Colletotrichum/crescimento & desenvolvimento , Fungicidas Industriais/farmacologia , Helianthus/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Colletotrichum/classificação , Colletotrichum/efeitos dos fármacos , Colletotrichum/isolamento & purificação
17.
Ecotoxicol Environ Saf ; 191: 110242, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004945

RESUMO

A novel green approach was utilized to fabricate sulfur nanoparticles (SNPs) with the aid of Ocimum basilicum leaves extract. The effective formation of the synthesized SNPs was examined and approved using UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. The average particle size was 23 nm with spherical shape and crystalline in nature. In the pot experiment, the synthesized SNPs were applied with different concentrations (12.5, 25, 50, 100 and 200 µM) as pre-soaking to Helianthus annuus seeds and irrigated with 100 mM MnSO4. As a result of manganese (Mn) exposure, the harvested 14-day sunflower seedlings showed a significant decline in the growth parameters (shoot length, leaf area and the relative water content of both shoot and root), photosynthetic pigments, mineral content (N, P, K, Ca, and Mg), and protein content compared to the control. The root length, electrolyte leakage, Na and Mn levels, metabolites content (amino acids, protein, glycine betaine, proline, and cysteine) were greatly raised as affected by Mn stress. Mn toxicity reduction using SNPs was demonstrated, as the medium doses enhanced seedlings growth, photosynthetic pigments, and mineral nutrients. Application of SNPs decreased Mn uptake and enhanced S metabolism through increasing cysteine level. Likewise, SNPs elevated seedlings water content and eliminated physiological drought via increasing osmolytes such as amino acids and proline. It can be concluded that green-synthesized SNPs had the potential to limit the deleterious effects of Mn stress.


Assuntos
Helianthus , Manganês/toxicidade , Nanopartículas/química , Ocimum basilicum/química , Enxofre/farmacologia , Química Verde , Helianthus/efeitos dos fármacos , Helianthus/crescimento & desenvolvimento , Tamanho da Partícula , Fotossíntese/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Prolina/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Enxofre/química , Água/metabolismo
18.
Food Chem ; 317: 126423, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097824

RESUMO

The impact of pH (6-9) and NaCl concentration (0-0.5 mol.L-1) on sunflower protein extraction was studied through design of experiments. The considered criteria were protein extraction yield (total proteins, helianthinin and albumins), chlorogenic acids covalently bound to proteins, and free chlorogenic acid concentration in the aqueous extract. Statistical analysis showed that the obtained by design of experiments the polynomial models of each extraction criteria were reliable for predicting the responses. They were employed in an original multi-objective optimization methodology. The optimal conditions revealed to be pH 7.3/0.3 mol.L-1 NaCl yielded 46.83% and 59.16% of total protein and albumin extraction yield, 1.730 and 1.998 mg.g-1 of chlorogenic acids covalently bound to helianthinin and albumins in aqueous extract, respectively. The sunflower protein isolate obtained after extraction in this condition had good solubility (40-80% at pH 5-8), functional properties (foaming and emulsifying) and a satisfying color.


Assuntos
Helianthus/metabolismo , Extração Líquido-Líquido/métodos , Proteínas de Plantas/isolamento & purificação , Extração em Fase Sólida/métodos , Albuminas/análise , Albuminas/isolamento & purificação , Albuminas/metabolismo , Ácido Clorogênico/química , Ácido Clorogênico/metabolismo , Concentração de Íons de Hidrogênio , Isomerismo , Extração Líquido-Líquido/instrumentação , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Polifenóis/análise , Polifenóis/metabolismo , Ligação Proteica , Cloreto de Sódio/química , Extração em Fase Sólida/instrumentação
19.
Gene ; 738: 144460, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32045659

RESUMO

MicroRNA390 (miR390), an ancient and highly conserved miRNA family in land plants, plays multiple roles in plant growth, development and stress responses. In this study, we isolated and identified MIR390, miR390, TAS3a/b/c, tasiARF-1/2/3 (trans-acting small interfering RNAs influencing Auxin Response Factors) and ARF2/3/4 in Jerusalem artichoke (Helianthus tuberosus L.). Treatment with 100 mM NaCl induced expression of miR390, increased cleavage of TAS3, produced high levels of tasiARFs, and subsequently enhanced cleavage of ARF3/4, which was most likely associated with salt tolerance of the plants. In contrast, treatment with 300 mM NaCl inhibited expression of miR390, attenuated cleavage of TAS3, produced a small amount of tasiARFs, and reduced cleavage of ARF3/4. We proposed that ARF2, one of the targets of tasiARFs, induced under salinity was likely to play an active role in salt tolerance of Jerusalem artichoke. The study of the miR390-TAS3-ARF model in Jerusalem artichoke may broaden our understanding of salt tolerance mechanisms, and provides a theoretical support for further genetic identification and breeding crops with increased tolerance to salt stress.


Assuntos
Helianthus/metabolismo , MicroRNAs/metabolismo , Estresse Salino/fisiologia , Regulação da Expressão Gênica de Plantas , Helianthus/genética , MicroRNAs/genética , Raízes de Plantas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Salinidade , Estresse Salino/genética , Tolerância ao Sal/genética
20.
J Vis Exp ; (155)2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32065151

RESUMO

Plant adaptation to biotic and abiotic stresses is governed by a variety of factors, among which the regulation of stomatal aperture in response to water deficit or pathogens plays a crucial role. Identifying small molecules that regulate stomatal movement can therefore contribute to understanding the physiological basis by which plants adapt to their environment. Large-scale screening approaches that have been used to identify regulators of stomatal movement have potential limitations: some rely heavily on the abscisic acid (ABA) hormone signaling pathway, therefore excluding ABA-independent mechanisms, while others rely on the observation of indirect, long-term physiological effects such as plant growth and development. The screening method presented here allows the large-scale treatment of plants with a library of chemicals coupled with a direct quantification of their transpiration by thermal imaging. Since evaporation of water through transpiration results in leaf surface cooling, thermal imaging provides a non-invasive approach to investigate changes in stomatal conductance over time. In this protocol, Helianthus annuus seedlings are grown hydroponically and then treated by root feeding, in which the primary root is cut and dipped into the chemical being tested. Thermal imaging followed by statistical analysis of cotyledonary temperature changes over time allows for the identification of bioactive molecules modulating stomatal aperture. Our proof-of-concept experiments demonstrate that a chemical can be carried from the cut root to the cotyledon of the sunflower seedling within 10 minutes. In addition, when plants are treated with ABA as a positive control, an increase in leaf surface temperature can be detected within minutes. Our method thus allows the efficient and rapid identification of novel molecules regulating stomatal aperture.


Assuntos
Helianthus/fisiologia , Imageamento Tridimensional , Transpiração Vegetal/fisiologia , Temperatura , Análise de Dados , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Estômatos de Plantas/fisiologia , Plântula/fisiologia , Água/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA