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1.
New Phytol ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256934

RESUMO

Advances in bryophyte genomics and the phylogenetic recovery of hornworts, mosses, and liverworts as a clade have spurred considerable recent interest in character evolution among early embryophytes. Discussion of stomatal evolution, however, has been incomplete; the result of the neglect of certain potential stomate homologues, namely the two-celled epidermal gametophytic pores of hornworts (typically referred to as 'mucilage clefts'). Confusion over the potential homology of these structures is the consequence of a relatively recent consensus that hornwort gametophytic pores ('HGPs' - our term) are not homologous to stomates. We explore the occurrence and diverse functions of stomates throughout the evolutionary history and diversity of extinct and extant embryophytes. We then address arguments for and against homology between known sporophyte- and gametophyte-borne stomates and HGPs and conclude that there is little to no evidence that contradicts the hypothesis of homology. We propose that 'intergenerational heterotopy' might well account for the novel expression of stomates in gametophytes of hornworts, if stomates first evolved in the sporophyte generation of embryophytes. We then explore phylogenetically based hypotheses for the evolution of stomates in both the gametophyte and sporophyte generations of early lineages of embryophytes.

2.
J Exp Bot ; 75(2): 584-593, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37549338

RESUMO

Drought is a major threat to food security worldwide. Recently, the root-soil interface has emerged as a major site of hydraulic resistance during water stress. Here, we review the impact of soil drying on whole-plant hydraulics and discuss mechanisms by which plants can adapt by modifying the properties of the rhizosphere either directly or through interactions with the soil microbiome.


Assuntos
Resistência à Seca , Solo , Raízes de Plantas , Secas , Produtos Agrícolas
3.
Phytopathology ; 114(8): 1832-1842, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38748933

RESUMO

Colletotrichum gloeosporioides is the causal agent of poplar anthracnose, which induces major economic losses and adversely affects the ecosystem services of poplar forests. The appressorium serves as a penetration structure for many pathogenic fungi, including C. gloeosporioides. The production of mucilage and the formation of penetration pegs are critically important for the appressorium-mediated penetration of host tissues. We previously found that CgPmk1 is a key protein involved in appressorium formation, penetration, and pathogenicity. Although CgSte12, which is a transcription factor that functions downstream of CgPmk1, regulates the formation of penetration pegs, its role in C. gloeosporioides appressorium development and pathogenicity has not been elucidated. Here, we developed C. gloeosporioides CgSTE12 mutants and characterized the molecular and cellular functions of CgSTE12. The results showed that mycelial growth and morphology were not affected in the CgSTE12 knockout mutants, which produced normal melanized appressoria. However, these mutants had less mucilage secreted around the appressoria, impaired appressorial cone formation, and the inability to form penetration pores and pegs, which ultimately led to a significant loss of pathogenicity. Our comparative transcriptome analysis revealed that CgSte12 controls the expression of genes involved in appressorium development and function, including genes encoding cutinases, NADPH oxidase, spermine biosynthesis-related proteins, ceramide biosynthesis-related proteins, fatty acid metabolism-related proteins, and glycerophospholipid metabolism-related proteins. Overall, our findings indicate that CgSte12 is a critical regulator of appressorium development and affects C. gloeosporioides pathogenicity by modulating the structural integrity of appressoria.


Assuntos
Colletotrichum , Proteínas Fúngicas , Doenças das Plantas , Populus , Fatores de Transcrição , Colletotrichum/patogenicidade , Colletotrichum/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Populus/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Virulência , Regulação Fúngica da Expressão Gênica , Mutação
4.
BMC Anesthesiol ; 24(1): 34, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254013

RESUMO

BACKGROUND: Dyclonine hydrochloride mucilage is a topical anaesthetic formulated for mucosal surfaces. It is employed frequently for topical anaesthesia of the pharynx prior to endoscopic examinations such as electronic gastroscopy, and few adverse reactions have been reported. This article describes a patient who experienced a transient but severe disturbance of consciousness following oral dyclonine hydrochloride mucilage administration. CASE PRESENTATION: A 75-year-old female presenting with gastrointestinal bleeding was examined by electronic gastroscopy. Six minutes after oral dyclonine hydrochloride mucilage administration, the patient entered a comatose-like state accompanied by loss of limb muscle tone and profuse perspiration. This response was not accompanied by changes in cardiac rhythm, blood pressure, or respiration rate, suggesting an effect on higher brain centres. After ten minutes, the patient's symptoms were alleviated. CONCLUSION: We suggest that sites of dyclonine hydrochloride mucilage use be equipped with appropriate rescue devices for these rare events.


Assuntos
Encéfalo , Estado de Consciência , Propiofenonas , Feminino , Humanos , Idoso , Administração Oral , Anestesia Local
5.
Ecotoxicol Environ Saf ; 285: 117130, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39366303

RESUMO

Environmental pollution poses a major problem now a day. Several dyes, in the form of industrial waste, pollute water body and may cause adverse effects to human health. In this paper ADME and toxicity of fives Phenothiazinium group of dyes Methylene blue (MB), Azure A (AA), Azure B (AB), Azure C (AC) and Toluidine Blue O (TBO) were predicted using Swiss ADME and Protox II tools. Results showed these dyes may herm for living organism due to their carcinogenic, mutagenic and hepatotoxic properties. Removal efficiency of these dyes using okra plant product were determined using spectroscopic, thermodynamic and molecular modeling study. It was revealed that these dyes adsorb on the surface of okra leaf mostly at pH 7.0 and the adsorption isotherms were found to fit in Langmuir and Freundlich isotherm model, while Temkin model fails to do this. Mucilage present in different parts of okra plant plays a significant role on removal of these dyes and is able to remove near about 71-92 % of dyes from water body by itself. As this process did not fit in any of above said adsorption isotherm model, it may be suggested that some other mechanism may happen. Further studies explore that these dyes bound to the hydrophobic pocket of mucilage with binding affinity in the order of 105 M-1 and the bindings were exothermic in nature with enthalpy change in the range of - 2.94 to - 4.28 kcal/mole. Molecular docking study validate all the experimental results obtained from spectroscopic and thermodynamic study and enlighten the role of structure of dyes on their binding affinity to mucilage. This paper will help to systematically understand the role of okra plant products on removal efficiency of Phenothiazinium group of dyes with their structural variations.


Assuntos
Corantes , Termodinâmica , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Corantes/química , Adsorção , Abelmoschus/química , Mucilagem Vegetal/química , Modelos Moleculares , Folhas de Planta/química
6.
Phytother Res ; 38(2): 662-693, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37966040

RESUMO

Diabetes mellitus is a globally metabolic endocrine syndrome marked by a deficiency of insulin secretion (type-1 DM) or glucose intolerance arising from insulin response impairment (type-2 DM) leading to abnormal glucose metabolism. With an increasing interest in natural dietary components for diabetes management, the identification of novel agents witnessed major discoveries. Plant-derived mucilage, pectin, and inulin are important non-starch polysaccharides that exhibit effective antidiabetic properties often termed soluble dietary fiber (SDF). SDF affects sugar metabolism through multiple mechanisms affecting glucose absorption and diffusion, modulation of carbohydrate metabolizing enzymes (α-amylase and α-glucosidase), ameliorating ß-pancreatic cell dysfunction, and improving insulin release or sensitivity. Certain SDFs inhibit dipeptidyl peptidase-4 and influence the expression levels of genes related to glucose metabolism. This review is designed to discuss holistically and critically the antidiabetic effects of major SDF and their underlying mechanisms of action. This review should aid drug discovery approaches in developing novel natural antidiabetic drugs from SDF.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/química , Inulina , Pectinas/farmacologia , Pectinas/uso terapêutico , Frutanos , Polissacarídeos , Insulina , Glucose , Diabetes Mellitus Tipo 2/tratamento farmacológico
7.
Phytochem Anal ; 35(1): 87-92, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37581346

RESUMO

INTRODUCTION: Nanoparticles are used in various fields such as chemistry, pharmacy, biotechnology, and food science since they provide higher sensitivity than traditional optical detection methods. Recently, synthesis of nanomaterials using green chemistry has become popular. Many phytochemical components are used in the synthesis of nanoparticles, including vitamins, proteins, polysaccharides, glycosides, essential oils and phenolic compounds. OBJECTIVE: A novel green nanotechnology-based method using quince seed mucilage (QSM) was designed for the determination of ascorbic acid in pharmaceutical preparations. QSM, a natural polysaccharide, was used as a bioreducing and stabilizing reagent in the proposed silver nanoparticle (SNP)-based method. METHOD: In the first stage of the developed method, silver(I) is reduced to silver(0) via QSM and spherical, homogeneous SNPs were prepared (QSM-SNPs). In the second stage of the developed method, SNPs nuclei were enlarged with the addition of ascorbic acid. The developed method was validated by performance parameters (linearity, recovery, and precision). Ascorbic acid determination was performed by measuring increase in absorbance at 420 nm. RESULTS: The limit of detection and limit of quantification for ascorbic acid were, respectively, found to be at 0.27 and 0.90 µM. The QSM-SNP-based method was successfully applied to effervescent tablets containing ascorbic acid. The standards of the excipients frequently used in pharmaceutical preparations did not interfere with the developed method. CONCLUSION: The developed QSM-SNP-based method satisfies the requirements of green nanotechnology. The developed QSM-SNP-based method is simple, fast, eco-friendly and low-cost.


Assuntos
Nanopartículas Metálicas , Rosaceae , Ácido Ascórbico/análise , Prata/análise , Prata/química , Nanopartículas Metálicas/química , Rosaceae/química , Sementes/química , Polissacarídeos/análise , Preparações Farmacêuticas/análise
8.
Int J Mol Sci ; 25(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256222

RESUMO

The Acyl-activating enzyme (AAE) 3 gene encodes an oxalyl-CoA synthetase that catalyzes the conversion of oxalate to oxalyl-CoA as the first step in the CoA-dependent pathway of oxalate catabolism. Although the role of this enzyme in oxalate catabolism has been established, its biological roles in plant growth and development are less understood. As a step toward gaining a better understanding of these biological roles, we report here a characterization of the Arabidopsis thaliana aae3 (Ataae3) seed mucilage phenotype. Ruthidium red (RR) staining of Ataae3 and wild type (WT) seeds suggested that the observed reduction in Ataae3 germination may be attributable, at least in part, to a decrease in seed mucilage accumulation. Quantitative RT-PCR analysis revealed that the expression of selected mucilage regulatory transcription factors, as well as of biosynthetic and extrusion genes, was significantly down-regulated in the Ataae3 seeds. Mucilage accumulation in seeds from an engineered oxalate-accumulating Arabidopsis and Atoxc mutant, blocked in the second step of the CoA-dependent pathway of oxalate catabolism, were found to be similar to WT. These findings suggest that elevated tissue oxalate concentrations and loss of the oxalate catabolism pathway downstream of AAE3 were not responsible for the reduced Ataae3 seed germination and mucilage phenotypes. Overall, our findings unveil the presence of regulatory interplay between AAE3 and transcriptional control of mucilage gene expression.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Sementes , Arabidopsis/genética , Germinação/genética , Oxalatos , Fenótipo , Polissacarídeos , Sementes/genética , Proteínas de Arabidopsis/genética
9.
Int J Mol Sci ; 25(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38279320

RESUMO

Carnivorous plants can survive in poor habitats because they have the ability to attract, capture, and digest prey and absorb animal nutrients using modified organs that are equipped with glands. These glands have terminal cells with permeable cuticles. Cuticular discontinuities allow both secretion and endocytosis. In Drosophyllum lusitanicum, these emergences have glandular cells with cuticular discontinuities in the form of cuticular gaps. In this study, we determined whether these specific cuticular discontinuities were permeable enough to antibodies to show the occurrence of the cell wall polymers in the glands. Scanning transmission electron microscopy was used to show the structure of the cuticle. Fluorescence microscopy revealed the localization of the carbohydrate epitopes that are associated with the major cell wall polysaccharides and glycoproteins. We showed that Drosophyllum leaf epidermal cells have a continuous and well-developed cuticle, which helps the plant inhibit water loss and live in a dry environment. The cuticular gaps only partially allow us to study the composition of cell walls in the glands of Drosophyllum. We recoded arabinogalactan proteins, some homogalacturonans, and hemicelluloses. However, antibody penetration was only limited to the cell wall surface. The localization of the wall components in the cell wall ingrowths was missing. The use of enzymatic digestion improves the labeling of hemicelluloses in Drosophyllum glands.


Assuntos
Caryophyllales , Parede Celular , Animais , Folhas de Planta , Plantas , Membrana Celular
10.
Molecules ; 29(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38731509

RESUMO

The aim of this study was to develop microcapsules containing juniper or black pepper essential oils, using a combination of faba bean protein and chia seed polysaccharides (in ratios of 1:1, 1:2, 2:1). By synergizing these two polymers, our goal was to enhance the efficiency of essential oil microencapsulation, opening up various applications in the food industry. Additionally, we aimed to investigate the influence of different polymer mixing ratios on the properties of the resulting microcapsules and the course of the complex coacervation process. To dissolve the essential oils and limit their evaporation, soybean and rapeseed oils were used. The powders resulting from the freeze-drying of coacervates underwent testing to assess microencapsulation efficiency (65.64-87.85%), density, flowability, water content, solubility, and hygroscopicity. Additionally, FT-IR and DSC analyses were conducted. FT-IR analysis confirmed the interactions between the components of the microcapsules, and these interactions were reflected in their high thermal resistance, especially at a protein-to-polysaccharide ratio of 2:1 (177.2 °C). The water content in the obtained powders was low (3.72-7.65%), but it contributed to their hygroscopicity (40.40-76.98%).


Assuntos
Cápsulas , Composição de Medicamentos , Óleos Voláteis , Proteínas de Plantas , Polissacarídeos , Salvia , Sementes , Vicia faba , Polissacarídeos/química , Sementes/química , Vicia faba/química , Composição de Medicamentos/métodos , Óleos Voláteis/química , Proteínas de Plantas/química , Salvia/química , Cápsulas/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
11.
Molecules ; 29(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38257357

RESUMO

Eating practices are changing due to awareness about meat consumption associated with social, ethical, environmental, and nutritional issues. Plant-based meat analogs are alternatives to conventional meat products that attempt to mimic all the inherent characteristics of meat fully. Therefore, the search for raw materials that provide these characteristics is increasing. Chia seeds have excellent potential as a functional ingredient in these products since they are a source of proteins, lipids, and fibers. Allied with this, the full use of chia through the seed and its fractions highlights the numerous beneficial characteristics of the formulation regarding nutritional characteristics and techno-functionality. Therefore, this review aims to highlight the potential of chia seed and its fractions for applications in meat-like products. Chia seeds are protein sources. Chia oil is rich in polyunsaturated fatty acids, and its application in emulsions ensures the oil's nutritional quality and maintains its technological characteristics. Defatted chia flour has a high protein content and can be used to extract chia mucilage. Due to its high emulsification capacity, chia mucilage is an effective ingredient for meat products and, consequently, meat-like products. Therefore, this literature review demonstrates the strategic potential of using chia seeds and their fractions to develop meat analogs.


Assuntos
Substitutos da Carne , Extratos Vegetais , Salvia hispanica , Sementes , Carne , Farinha
12.
Entropy (Basel) ; 26(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38785629

RESUMO

The goal of the research is to describe the aggregation process inside the mucilage produced by plant seeds using molecular dynamics (MD) combined with time series algorithmic analysis based on the recurrence plots. The studied biological molecules model is seed mucilage composed of three main polysaccharides, i.e. pectins, hemicellulose, and cellulose. The modeling of biological molecules is based on the assumption that a classical-quantum passage underlies the aggregation process in the mucilage, resulting from non-covalent interactions, as they affect the macroscopic properties of the system. The applied recurrence plot approach is an important tool for time series analysis and data mining dedicated to analyzing time series data originating from complex, chaotic systems. In the current research, we demonstrated that advanced algorithmic analysis of seed mucilage data can reveal some features of the dynamics of the system, namely temperature-dependent regions with different dynamics of increments of a number of hydrogen bonds and regions of stable oscillation of increments of a number of hydrophobic-polar interactions. Henceforth, we pave the path for automatic data-mining methods for the analysis of biological molecules with the intermediate step of the application of recurrence plot analysis, as the generalization of recurrence plot applications to other (biological molecules) datasets is straightforward.

13.
Plant J ; 110(5): 1382-1396, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35306706

RESUMO

The exocyst complex is an octameric evolutionarily conserved tethering complex engaged in the regulation of polarized secretion in eukaryotic cells. Here, we focus on the systematic comparison of two isoforms of the SEC15 exocyst subunit, SEC15a and SEC15b. We infer that SEC15 gene duplication and diversification occurred in the common ancestor of seed plants (Spermatophytes). In Arabidopsis, SEC15a represents the main SEC15 isoform in the male gametophyte, and localizes to the pollen tube tip at the plasma membrane. Although pollen tubes of sec15a mutants are impaired, sporophytes show no phenotypic deviations. Conversely, SEC15b is the dominant isoform in the sporophyte and localizes to the plasma membrane in root and leaf cells. Loss-of-function sec15b mutants exhibit retarded elongation of hypocotyls and root hairs, a loss of apical dominance, dwarfed plant stature and reduced seed coat mucilage formation. Surprisingly, the sec15b mutants also exhibit compromised pollen tube elongation in vitro, despite its very low expression in pollen, suggesting a non-redundant role for the SEC15b isoform there. In pollen tubes, SEC15b localizes to distinct cytoplasmic structures. Reciprocally to this, SEC15a also functions in the sporophyte, where it accumulates at plasmodesmata. Importantly, although overexpressed SEC15a could fully complement the sec15b phenotypic deviations in the sporophyte, the pollen-specific overexpression of SEC15b was unable to fully compensate for the loss of SEC15a function in pollen. We conclude that the SEC15a and SEC15b isoforms evolved in seed plants, with SEC15a functioning mostly in pollen and SEC15b functioning mostly in the sporophyte.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Pólen/metabolismo , Tubo Polínico/genética , Tubo Polínico/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sementes/genética , Sementes/metabolismo
14.
Plant Mol Biol ; 112(6): 309-323, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378835

RESUMO

Aerial root mucilage can enhance nitrogen fixation by providing sugar and low oxygen environment to the rhizosphere microbiome in Sierra Mixe maize. Aerial root mucilage has long been documented in sorghum (Sorghum bicolor), but little is known about the biological significance, genotypic variation, and genetic regulation of this biological process. In the present study, we found that a large variation of mucilage secretion capacity existed in a sorghum panel consisting of 146 accessions. Mucilage secretion occurred primarily in young aerial roots under adequately humid conditions but decreased or stopped in mature long aerial roots or under dry conditions. The main components of the mucilage-soluble were glucose and fructose, as revealed by sugar profiling of cultivated and wild sorghum. The mucilage secretion capacity of landrace grain sorghum was significantly higher than that of wild sorghum. Transcriptome analysis revealed that 1844 genes were upregulated and 2617 genes were downregulated in mucilage secreting roots. Amongst these 4461 differentially expressed genes, 82 genes belonged to glycosyltransferases and glucuronidation pathways. Sobic.010G120200, encoding a UDP-glycosyltransferase, was identified by both GWAS and transcriptome analysis as a candidate gene, which may be involved in the regulation of mucilage secretion in sorghum through a negative regulatory mechanism.


Assuntos
Sorghum , Sorghum/genética , Sorghum/metabolismo , Transcriptoma , Açúcares/metabolismo , Estudo de Associação Genômica Ampla , Polissacarídeos/metabolismo , Perfilação da Expressão Gênica , Grão Comestível/genética , Variação Genética
15.
Plant Cell Physiol ; 64(8): 906-919, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37354456

RESUMO

MYB-bHLH-TTG1 (MBW) transcription factor (TF) complexes regulate Arabidopsis seed coat biosynthesis pathways via a multi-tiered regulatory mechanism. The MYB genes include MYB5, MYB23 and TRANSPARENT TESTA2 (TT2), which regulate GLABRA2 (GL2), HOMEODOMAIN GLABROUS2 (HDG2) and TRANSPARENT TESTA GLABRA2 (TTG2). Here, we examine the role of PECTIN METHYLESTERASE INHIBITOR14 (PMEI14) in seed coat mucilage pectin methylesterification and provide evidence in support of multi-tiered regulation of seed coat mucilage biosynthesis genes including PMEI14. The PMEI14 promoter was active in the seed coat and developing embryo. A pmei14 mutant exhibited stronger attachment of the outer layer of seed coat mucilage, increased mucilage homogalacturonan demethylesterification and reduced seed coat radial cell wall thickness, results consistent with decreased PMEI activity giving rise to increased PME activity. Reduced mucilage release from the seeds of myb5, myb23, tt2 and gl2, hdg2, ttg2 triple mutants indicated that HDG2 and MYB23 play minor roles in seed coat mucilage deposition. Chromatin immunoprecipitation analysis found that MYB5, TT8 and seven mucilage pathway structural genes are directly regulated by MYB5. Expression levels of GL2, HDG2, TTG2 and nine mucilage biosynthesis genes including PMEI14 in the combinatorial mutant seeds indicated that these genes are positively regulated by at least two of those six TFs and that TTG1 and TTG2 are major regulators of PMEI14 expression. Our results show that MYB-bHLH-TTG1 complexes regulate mucilage biosynthesis genes, including PMEI14, both directly and indirectly via a three-tiered mechanism involving GL2, HDG2 and TTG2.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mucilagem Vegetal , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Mutação , Pectinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Sementes/genética , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas , Mucilagem Vegetal/metabolismo
16.
Planta ; 257(5): 89, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36988700

RESUMO

MAIN CONCLUSION: Transcript isoform dynamics, spatiotemporal expression, and mutational analysis uncover that Arabidopsis RabC1 GTPase is required for root length, flowering time, seed size, and seed mucilage. Rab GTPases are crucial regulators for moving different molecules to their specific compartments according to the needs of the cell. In this work, we illustrate the role of RabC1 GTPase in Arabidopsis growth and seed development. We identify and analyze the expression pattern of three transcript isoforms of RabC1 in different development stages, along with their tissue-specific transcript abundance. The promoter activity of RabC1 using promoter-GUS fusion shows that it is widely expressed during the growth of Arabidopsis, particularly in seed tissues such as chalazal seed coat and chalazal endosperm. Lack of RabC1 function led to shorter roots, lesser biomass, delayed flowering, and sluggish plant development. The mutants had smaller seeds than the wildtype, less seed mass, and lower seed coat permeability. Developing seeds also revealed a smaller endosperm cavity and shorter integument cells. Additionally, we found that the knock-out mutant had downregulated expression of genes implicated in the transit of sugars and amino acids from maternal tissue to developing seed. The seeds of the loss-of-function mutant had reduced seed mucilage. All the observed mutant phenotypes were restored in the complemented lines confirming the function of RabC1 in seed development and plant growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sementes , Endosperma/genética , Desenvolvimento Vegetal , Regulação da Expressão Gênica de Plantas
17.
Planta ; 258(6): 112, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935872

RESUMO

MAIN CONCLUSION: Extracellular traps in the primary root of Pinus densiflora contribute to root-associated bacterial colonization. Trapped rhizobacteria induce the production of reactive oxygen species in root-associated, cap-derived cells. Ectomycorrhizal (ECM) woody plants, such as members of Pinaceae and Fagaceae, can acquire resistance to biotic and abiotic stresses through the formation of mycorrhiza with ECM fungi. However, germinated tree seedlings do not have mycorrhizae and it takes several weeks for ectomycorrhizae to form on their root tips. Therefore, to confer protection during the early growth stage, bare primary roots require defense mechanisms other than mycorrhization. Here, we attempted to visualize root extracellular traps (RETs), an innate root defense mechanism, in the primary root of Pinus densiflora and investigate the interactions with root-associated bacteria isolated from ECM and fine non-mycorrhizal roots. Histological and histochemical imaging and colony-forming unit assays demonstrated that RETs in P. densiflora, mainly consisting of root-associated, cap-derived cells (AC-DCs) and large amounts of root mucilage, promote bacterial colonization in the rhizosphere, despite also having bactericidal activity via extracellular DNA. Four rhizobacterial strains retarded the mycelial growth of a pathogenic strain belonging to the Fusarium oxysporum species complex in dual culture assay. They also induced the production of reactive oxygen species (ROS) from host tree AC-DCs without being excluded from the rhizosphere of P. densiflora. Applying three Paraburkholderia strains, especially PM O-EM8 and PF T-NM22, showed significant differences in the ROS levels from the control group. These results reveal the indirect contributions of rhizobacteria to host root defense and suggest that root-associated bacteria could be a component of RETs as a first line of defense against root pathogens in the early growth stage of ECM woody plants.


Assuntos
Armadilhas Extracelulares , Micorrizas , Pinus , Micorrizas/genética , Espécies Reativas de Oxigênio , Raízes de Plantas , Bactérias , Árvores/microbiologia
18.
Yeast ; 40(9): 425-436, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37464909

RESUMO

During wet fermentation, mucilage layers in coffee cherries must be removed completely. To explain mucilage degradation, several controversial hypotheses have been proposed. The aim of this work was to improve our understanding of the kinetics of mucilage breakdown. Pulped coffee beans were wet fermented with seven different treatments for 36 h. Endogenous bacteria and yeasts are selectively suppressed, and pectinases or lactic acid are added. They also involve maintaining the beans at pH 7 throughout fermentation and using spontaneous fermentation without additives as a control. During spontaneous fermentation, yeast and lactic acid bacteria were detected and significantly increased to 5.5 log colony-forming units (CFU)/mL and 5.2 log CFU/mL, respectively. In the first 12 h of fermentation, there was a significant degree of endogenous pectinolytic activity, which resulted in partly destroyed beans in the absence of microorganisms. By adding pectinase and lactic acid to the fermentation mass, the breakdown process was accelerated in less than 8 h. When yeast was present throughout the fermentation, complete degradation was achieved. Bacteria played no critical role in the degradation. Klebsiella pneumoniae and Erwinia soli were found in a lower population and showed weaker pectinolytic activities compared to Hanseniaspora uvarum and Pichia kudriavzevii. During wet fermentation, mucilage degradation appears to be mediated by endogenous enzymes at the early stage, whereas microbial contributions, mainly yeasts, occur subsequently. H. uvarum and P. kudriavzevii may be promising candidates to be tested in future studies as coffee starter cultures to better control the mucilage degradation process.


Assuntos
Coffea , Fermentação , Coffea/química , Coffea/metabolismo , Coffea/microbiologia , Leveduras/metabolismo , Bactérias/metabolismo , Polissacarídeos , Ácido Láctico/metabolismo
19.
Biopolymers ; 114(8): e23561, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37435955

RESUMO

Mucilage, a polysaccharide-containing hydrogel, is hypothesized to play a key role in the rhizosphere as a self-organized system because it may vary its supramolecular structure with changes in the surrounding solution. However, there is currently limited research on how these changes are reflected in the physical properties of real mucilage. This study examines the role of solutes in maize root, wheat root, chia seed, and flax seed mucilage in relation to their physical properties. Two purification methods, dialysis and ethanol precipitation, were applied to determine the purification yield, cation content, pH, electrical conductivity, surface tension, viscosity, transverse 1 H relaxation time, and contact angle after drying of mucilage before and after purification. The two seed mucilage types contain more polar polymers that are connected to larger assemblies via multivalent cation crosslinks, resulting in a denser network. This is reflected in higher viscosity and water retention ability compared to root mucilage. Seed mucilage also contains fewer surfactants, making them better wettable after drying compared to the two root mucilage types. The root mucilage types, on the other hand, contain smaller polymers or polymer assemblies and become less wettable after drying. However, wettability not only depends on the amount of surfactants but also on their mobility, as well as the strength and mesh size of the network structure. The changes in physical properties and cation composition observed after ethanol precipitation and dialysis suggest that the polymer network of seed mucilage is more stable and specialized in protecting the seeds from unfavorable environmental conditions. In contrast, root mucilage is characterized by fewer cationic interactions and its network relies more on hydrophobic interactions. This allows root mucilage to be more flexible in responding to changing environmental conditions, facilitating nutrient and water exchange between root surfaces and the rhizosphere soil.


Assuntos
Rizosfera , Sementes , Sementes/química , Extratos Vegetais , Polissacarídeos/química , Água/química
20.
Int J Mol Sci ; 24(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37108546

RESUMO

Nanoencapsulation can increase the stability of bioactive compounds, ensuring protection against physical, chemical, or biological degradations, and allows to control of the release of these biocompounds. Chia oil is rich in polyunsaturated fatty acids-8% corresponds to omega 3 and 19% to omega 6-resulting in high susceptibility to oxidation. Encapsulation techniques allow the addition of chia oil to food to maintain its functionality. In this sense, one strategy is to use the nanoemulsion technique to protect chia oil from degradation. Therefore, this review aims to present the state-of-the-art use of nanoemulsion as a new encapsulation approach to chia oil. Furthermore, the chia mucilage-another chia seed product-is an excellent material for encapsulation due to its good emulsification properties (capacity and stability), solubility, and water and oil retention capacities. Currently, most studies of chia oil focus on microencapsulation, with few studies involving nanoencapsulation. Chia oil nanoemulsion using chia mucilage presents itself as a strategy for adding chia oil to foods, guaranteeing the functionality and oxidative stability of this oil.


Assuntos
Óleos de Plantas , Salvia , Óleos de Plantas/química , Salvia/química , Polissacarídeos/análise , Extratos Vegetais/análise , Sementes/química
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