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1.
Braz. j. biol ; 83: e251075, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339401

RESUMO

Abstract Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.


Resumo Produtos derivados de plantas podem auxiliar no processo de cicatrização de feridas cutâneas. Foi demonstrado que o látex de Hancornia speciosa apresenta atividades angiogênicas, osteogênicas, antiinflamatórias e antioxidantes. Então, este biomaterial pode contribuir para o processo de cicatrização de feridas. No entanto, produtos naturais em contato com a pele podem causar dermatites. O objetivo deste trabalho foi avaliar o potencial alérgico e irritante do látex da fração soro de H. speciosa por meio de ensaios in vitro. Os resultados obtidos mostraram que o látex da fração do soro de H. speciosa possui um potencial pouco irritante e não é citotóxico nem alergênico para células humanas. Além disso, foi identificado uma notável baixa quantidade de proteínas neste material em comparação ao látex de Hevea brasiliensis. Esse resultado poderia explicar o potencial não alergênico do látex da fração soro de H. speciosa, pois as proteínas presentes no látex são as principais responsáveis ​​pela alergia. Este biomaterial pode ser utilizado como fonte não alergênica para desenvolvimento de novos medicamentos.


Assuntos
Humanos , Apocynaceae , Hevea , Cicatrização , Materiais Biocompatíveis , Alérgenos , Látex
2.
Environ Res ; 216(Pt 3): 114775, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370812

RESUMO

The current study emphasizes the activated carbon fabrication from rubber fig leaves, the establishment of its composite with iron oxide nanoparticles (RFAC@Fe2O3), and its relevance in the adsorptive elimination of tetracycline. The physical and functional properties of RFAC@Fe2O3 nanocomposite were uncovered by multiple approaches. Elemental analysis portrayed the existence of carbon, oxygen, and iron, while FESEM analysis revealed that Fe2O3 nanoparticle agglomerates were entrenched in the activated carbon matrix rendering it a rough abrasive texture. FT-IR analysis reported the presence of functional groups attributing to CC, -OH, crystalline iron oxide, and Fe-O stretching vibrations, and XRD corroborated graphitic crystalline structure, oxygenated functional groups attached to carbon accompanied by crystalline plane corresponding to Fe2O3 nanoparticles. XPS spectra depicted signature peaks for C, O, and Fe, while VSM studies designated its superparamagnetic nature. The high surface area (662.73 m2/g), pore size (3.12 nm), and mesoporous nature of RFAC@Fe2O3 make it apt for the adsorption of pollutants from contaminated samples. The adsorption of tetracycline (50 ppm) by RFAC@Fe2O3 was maximum at pH 4.0. As the nanocomposite dosage and stirring speed increased to 2.0 g/L and 150 rpm, maximum adsorption was observed due to more active binding sites and improved mixing. Freundlich isotherm along with pseudo-second-order model well described adsorption process divulging that tetracycline was adsorbed onto RFAC@Fe2O3 composite in multi-layers by chemisorption. Thermodynamic analysis signified negative values for ΔG°, while positive values for ΔH° and ΔS were obtained, indicating spontaneous feasible endothermic adsorption.


Assuntos
Ficus , Hevea , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Borracha , Árvores , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Cinética , Tetraciclina/química , Água , Termodinâmica , Antibacterianos/análise , Folhas de Planta , Fenômenos Magnéticos , Concentração de Íons de Hidrogênio
3.
Molecules ; 27(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36364185

RESUMO

The secondary metabolites of the phytopathogenic fungus Corynespora cassiicola CC01 from Hevea brasiliensis were investigated. As a result, two new compounds, 5-acetyl-7-hydroxy-6- methoxybenzofuran-2(3H)-one (1) and (S)-2-(2,3-dihydrofuro [3,2-c]pyridin-2-yl)propan-2-ol (2), together with seven known compounds, 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (3), 3,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (4), curvulin acid (5), 2-methyl-5-carboxymethyl- 7-hydroxychromone (6), tyrosol (7), p-hydroxybenzoic acid (8) and cerevisterol (9), were isolated from the fermentation extract by comprehensive silica gel, reverse phase silica gel, Sephadex-LH20 column chromatography and high-performance liquid chromatography (HPLC). The structures of these compounds were identified by using high-resolution electrospray mass spectrometry (HRESIMS), nuclear magnetic resonance spectroscopy (NMR), optical rotation, ultraviolet and infrared spectroscopy techniques and a comparison of NMR data with those reported in the literature. Compounds 1 and 2 were new compounds, and compounds 3-9 were discovered from this phytopathogenic fungus for the first time. Compounds 1-9 were tested for phytotoxicity against the fresh tender leaf of Hevea brasiliensis, and the results show that none of them were phytotoxic. Additionally, these compounds were subjected to an antimicrobial assay against three bacteria (E. coli, methicillin-resistant Staphylococcus aureus and Micrococcus luteus), but they showed no activity.


Assuntos
Ascomicetos , Hevea , Staphylococcus aureus Resistente à Meticilina , Hevea/química , Sílica Gel , Escherichia coli
4.
Int J Mol Sci ; 23(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36293447

RESUMO

The RPW8s (Resistance to Powdery Mildew 8) are atypical broad-spectrum resistance genes that provide resistance to the powdery mildew fungi. Powdery mildew of rubber tree is one of the serious fungal diseases that affect tree growth and latex production. However, the RPW8 homologs in rubber tree and their role of resistance to powdery mildew remain unclear. In this study, four RPW8 genes, HbRPW8-a, b, c, d, were identified in rubber tree, and phylogenetic analysis showed that HbRPW8-a was clustered with AtRPW8.1 and AtRPW8.2 of Arabidopsis. The HbRPW8-a protein was localized on the plasma membrane and its expression in rubber tree was significantly induced upon powdery mildew infection. Transient expression of HbRPW8-a in tobacco leaves induced plant immune responses, including the accumulation of reactive oxygen species and the deposition of callose in plant cells, which was similar to that induced by AtRPW8.2. Consistently, overexpression of HbRPW8-a in Arabidopsis thaliana enhanced plant resistance to Erysiphe cichoracearum UCSC1 and Pseudomonas syringae pv. tomato DC30000 (PstDC3000). Moreover, such HbRPW8-a mediated resistance to powdery mildew was in a salicylic acid (SA) dependent manner. Taken together, we demonstrated a new RPW8 member in rubber tree, HbRPW8-a, which could potentially contribute the resistance to powdery mildew.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ascomicetos , Hevea , Arabidopsis/metabolismo , Hevea/genética , Hevea/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Expressão Ectópica do Gene , Filogenia , Espécies Reativas de Oxigênio/metabolismo , Látex/metabolismo , Doenças das Plantas/microbiologia , Ascomicetos/fisiologia , Erysiphe , Ácido Salicílico/metabolismo , Tabaco/metabolismo , Resistência à Doença/genética
5.
Poult Sci ; 101(12): 102212, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36283140

RESUMO

This study is part of a series of studies on the possibility of substituting alternative protein source supplements to the diet of guinea fowl in order to improve food security in the fight against poverty on the African Continent. This study assesses the identified sensory characteristics of guinea fowl meat and consumer preferences to determine if the possible alternative supplements identified result in a product acceptable to consumers and if consumer preference was evident. Indigenous guinea fowl or selected breed (Galor animals) were fed a control diet C, a commercial diet I (diet used for guinea fowl in Côte d'Ivoire), or one of 2 experimental diets N (diet C supplemented with 15% cashew nut meal) or diet H (diet C supplemented with 15% detoxified hevea seed meal). Meat samples were assessed by 120-trained people using 18 sensory attributes. Principal component analysis (PCA) showed that meats from guinea fowl fed diet C or diet I were clearly distinguished from guinea fowl fed N or H diets and that meat of indigenous guinea fowl or Galor animals were also clearly distinguished. The results of the hierarchical group analysis showed that meat from guinea fowl fed diet H was the preferred guinea fowl meat. A first partial least squares regression PLSR1 identified the relationships between guinea fowl meat samples, their sensory attributes and consumer preference and showed that 82.6% of the sensory data of the first 2 principal components accounted for 95.5% of the preference. The PLSR2 identified the relationships between guinea fowl samples, their sensory attributes, and their biochemical characteristics and showed that the fat content of the meat determined the intensity of flavor, odor, juiciness, and tenderness of the meat. Our results showed that meat from birds fed diet H was preferred, and thus emphasized the existence of a place for the use of hevea seed meal in guinea fowl diet in Côte d'Ivoire.


Assuntos
Anacardium , Galliformes , Hevea , Animais , Comportamento do Consumidor , Anacardium/química , Ração Animal/análise , Nozes , Galinhas , Melhoramento Vegetal , Carne/análise , Dieta/veterinária , Sementes
6.
Sci Rep ; 12(1): 18023, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289298

RESUMO

Rubber tree (Hevea brasiliensis) is the main feedstock for commercial rubber; however, its long vegetative cycle has hindered the development of more productive varieties via breeding programs. With the availability of H. brasiliensis genomic data, several linkage maps with associated quantitative trait loci have been constructed and suggested as a tool for marker-assisted selection. Nonetheless, novel genomic strategies are still needed, and genomic selection (GS) may facilitate rubber tree breeding programs aimed at reducing the required cycles for performance assessment. Even though such a methodology has already been shown to be a promising tool for rubber tree breeding, increased model predictive capabilities and practical application are still needed. Here, we developed a novel machine learning-based approach for predicting rubber tree stem circumference based on molecular markers. Through a divide-and-conquer strategy, we propose a neural network prediction system with two stages: (1) subpopulation prediction and (2) phenotype estimation. This approach yielded higher accuracies than traditional statistical models in a single-environment scenario. By delivering large accuracy improvements, our methodology represents a powerful tool for use in Hevea GS strategies. Therefore, the incorporation of machine learning techniques into rubber tree GS represents an opportunity to build more robust models and optimize Hevea breeding programs.


Assuntos
Hevea , Hevea/genética , Hevea/metabolismo , Borracha/metabolismo , Melhoramento Vegetal , Genômica , Aprendizado de Máquina
7.
Poult Sci ; 101(9): 102040, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35917674

RESUMO

This study was conducted to investigate the effect of PUFA-enriched rubber (Hevea brasiliensis) seed oil (RSO) supplementation in diets on the productive performance, plasma biochemical parameters, immune response, and inflammation in lipopolysaccharide (LPS)-challenged laying hens. Two hundred and forty 25-wk-old Lohmann Brown laying hens were randomly divided into 5 treatments, each including 4 replicates with 12 birds per replicate. The control group and LPS-challenged group were fed a corn-soybean-basal diet; 3 RSO-supplemented groups were fed experimental diets containing 1, 2, and 4% RSO for a feeding period of 4 wk. On the 15, 18, 21, 24, and 27 d of the RSO supplementation period of 4 wk, hens were injected intraperitoneally with LPS at 1 mg/kg body weight (challenge group and RSO-supplemented groups) or with the same amount of saline (control group). The results showed that the addition of RSO promoted laying performance by increasing egg production, total egg weight, daily egg mass, and feed intake in comparison to the LPS-challenged laying hens (P < 0.05). In addition, compared with laying hens stimulated with LPS, the analysis of blood cell and plasma parameters revealed that hens in RSO-supplemented groups had significantly lower levels (P < 0.05) of white blood cells (WBC), lymphocytes (LYM), aspartate aminotransferase (AST) activity, immunoglobulin A (IgA), triiodothyronine (T3), interleukin-2 (IL-2), and tumor necrosis factor-α (TNF-α). Further, RSO supplementation significantly reduced the mRNA expression of toll-like receptor 4 (TLR4), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) of the ileum, spleen, and liver in LPS-challenged laying hens (P < 0.05), suggesting that the anti-inflammatory mechanism of RSO is related to the TLR4/NF-κB signaling pathway. In conclusion, RSO supplementation in diets could improve laying performance, attenuate immunological stress, and inhibit the inflammatory response in LPS-challenged laying hens, especially at the dietary inclusion of 4% RSO. This study will provide an insight into the application of RSO to positively contribute to overall health and welfare in laying hens.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Hevea , Ração Animal/análise , Animais , Galinhas/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Lipopolissacarídeos , NF-kappa B/metabolismo , Óleos Vegetais/metabolismo , Borracha/metabolismo , Receptor 4 Toll-Like/metabolismo
8.
Int J Biol Macromol ; 221: 796-805, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36037910

RESUMO

The tung oil produced by the tung tree (Vernicia fordii) provides resources for the manufacture of biodiesel. Ubiquitin-specific proteases (UBPs) are the largest group of deubiquitinases and play key roles in regulating development and stress responses. Here, 21 UBPs were identified in V. fordii, roughly one-half the number found in Manihot esculenta and Hevea brasiliensis. Most UBP duplications are produced from whole-genome duplication (WGD), and significant differences in gene retention existed among Euphorbiaceae. The great majority of UBP-containing blocks in V. fordii, V. montana, Ricinus communis, and Jatropha curcas exhibited extensive conservation with the duplicated regions of M. esculenta and H. brasiliensis. These blocks formed 14 orthologous groups, indicating they shared WGD with UBPs in M. esculenta and H. brasiliensis, but most of these UBPs copies were lost. The UBP orthologs contained significant functional divergence which explained the susceptibility of V. fordii to Fusarium wilt and the resistance of V. montana to Fusarium wilt. The expression patterns and experiments suggested that Vf03G1417 could affect the seed-related traits and positively regulate the seed oil accumulation. This study provided important insights into the evolution of UBPs in Euphorbiaceae and identified important candidate VfUBPs for marker-assisted breeding in V. fordii.


Assuntos
Aleurites , Euphorbiaceae , Hevea , Proteases Específicas de Ubiquitina , Melhoramento Vegetal , Aleurites/genética , Sementes/genética , Sementes/metabolismo , Hevea/metabolismo , Euphorbiaceae/genética
9.
An Acad Bras Cienc ; 94(4): e20200515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830067

RESUMO

The main factors governing Hevea brasiliensis germination and seedling establishment remains unclear. We examined the effect of growth regulators Indole 3-Acetic Acid (IAA) and 6-Benzylaminopurine (BAP), and their interactions on germination and the development of mature zygotic embryos (MZE) and protein profile of Hevea brasiliensis seedlings from wild and cultivated (clone PB 250) genotypes. Embryonic axes excised from seeds (wild and clone PB 250) were inoculated in Murashige and Skoog medium (control) and supplemented with IAA (3 µM) and BAP (6 µM) individually and their combination (3 µM IAA + 6 µM BAP). For both genotypes, the mature embryos displayed a high percentage of germination and establishment, and the seedlings were characterized by protein bands ranging from 7 to 30 kDa. Notably, the wild genotype showed proteins in the 14 kDa range, which may be associated with one of the major rubber elongation factors (REF). The wild and clone genotypes presented different behavior and strategies in relation to the protein profile in the presence of different growth regulators. Although the latex biosynthetic pathway and its mechanisms of regulation still remain largely unknown, our results aid in our understanding of the dynamics of proteins in different rubber tree clones in vitro.


Assuntos
Hevea , Germinação , Hevea/genética , Hevea/metabolismo , Látex/farmacologia , Proteínas de Plantas/genética , Plântula/genética , Sementes/metabolismo
10.
J Sep Sci ; 45(18): 3491-3500, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35855582

RESUMO

The current method used in latex industries to determine the volatile fatty acids contents of Hevea brasiliensis latex is steam distillation. However, the accuracy of the method has been debated for some time. We assessed the accuracy of the method and developed a new, more reliable high-performance liquid chromatographic method of determining acids in latex. The volatile fatty acids (formic, acetic, propionic, butyric, and valeric acids) and nonvolatile organic acids (oxalic, malic, lactic, citric, and succinic acids) in latex are directly determined simultaneously for the first time with high sensitivity and without losses during sample preparation. To avoid errors from derivatization, an acid-resistant Prevail HPLC column and a gradient mobile phase of 25 mM potassium dihydrogen phosphate (pH 2.5) and acetonitrile were employed. Under optimum conditions, the calibrations of both types of acids demonstrated satisfactory correlation coefficients of  ≥0.990, with limits of detection ranging from 0.02 to 395 mM. The developed method demonstrated the profiles of acids in field and concentrated latex of the same batch. Moreover, the evolution of the profiles of all studied acids in both types of latex during a 3-month period was also revealed.


Assuntos
Hevea , Látex , Acetonitrilas , Ácidos/análise , Ácidos Graxos Voláteis , Hevea/química , Látex/química , Compostos Orgânicos/análise , Vapor , Succinatos
11.
Gene ; 827: 146475, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35378248

RESUMO

Heat shock protein 90 (HSP90), an essential molecular chaperone, is triggered in response to stress situations in plants. However, the roles of HSP90 gene family members in rubber tree have not been totally specified. In this study, 7 HbHSP90 genes were identified from rubber tree genome. Classification of HbHSP90 family genes into three groups, namely A, B, and C was based on phylogenetic analysis. The structural and motif analyses showed similar structural features in the same group of HbHSP90 members, but differences between groups. Analysis of cis-regulatory element sequences of HbHSP90 genes indicates that the HbHSP90 gene promoter is rich in drought, temperature, and hormone elements. qRT-PCR analysis showed that the 7 HbHSP90 genes responded in different degrees to temperature, drought and powdery mildew infection, and in particularly, HbHSP90.1 was differentially expressed under both abiotic and biotic stresses. Meanwhile, HbHSP90.1 gene was significantly expressed under the treatment of different phytohormone and H2O2 (Hydrogen Peroxide) treatments, which means that HbHSP90.1 gene performs an essential part in the growth and development of rubber trees. Furthermore, the protein interaction results showed that HbHSP90.1 interacted with HbSGT1b. Subcellular localization showed that both HbHSP90.1 and HbSGT1b located in the nucleus. Taken together, we speculate that HbHSP90.1 interacts with HbSGT1b in the nucleus to respond to rubber tree stress processes. The results of this study provide a solid foundation for further studies on the mechanism of HbHSP90 family genes in the stress resistance response of rubber tree.


Assuntos
Hevea , Regulação da Expressão Gênica de Plantas , Hevea/genética , Hevea/metabolismo , Peróxido de Hidrogênio/metabolismo , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
Methods Mol Biol ; 2484: 237-257, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35461456

RESUMO

The genetic incompatibility of the seedlings which are used as rootstocks (stock-scion interactions) and the mechanical stress induced by grafting are two major factors responsible for the high intraclonal variations observed in tree crops which are propagated through bud grafting. Since stress-induced DNA methylation changes associated with heterografting is a major contributor of such variations in grafted tree crops, a proper assessment of this epigenetic phenomenon is inevitable to devise strategies for the development of more uniform planting materials with minimal intraclonal variations in the future. In order to evaluate and establish the effects of heterografting on the epigenome of plants, availability of ideal plant materials and a standard procedure for testing is very essential. Development of genetically uniform own-rooted seedlings through induction of cleavage polyembryony by a novel technique of half ovulo embryo culture is the first step. Grafting of buds from these genetically and epigenetically uniform plants to genetically divergent rootstock and identification of DNA methylation polymorphism among them forms the second part of the methodology for detecting epigenetic changes associated with grafting in tree crops. Methylation-sensitive amplification polymorphism technique (MSAP), a modified version of AFLP using a pair of methylation-sensitive and insensitive isoschizomers (such as HpaII and MspI), is an ideal methodology to assess DNA methylation polymorphisms on a genomic scale in such plants. Comparative analysis of two sets of restriction digestion products (EcoRI/HpaII and EcoRI/MspI) allows the identification of DNA methylation polymorphisms induced by grafting and will aid in the detection of differentially methylated regions (DMRs) among grafted plants. This chapter describes a detailed protocol for inducing multiple embryos of single zygotic origin and regeneration of seedlings in rubber tree (Hevea brasiliensis), grafting of buds from these genetically uniform own-rooted seedlings to divergent rootstocks, identification of epigenetic changes induced by grafting or stock-scion interactions through MSAP analysis, and locating the differentially methylated genomic region. The methodology described here could be applied to any tree species commercially propagated through grafting for detecting epigenetic changes putatively associated with intraclonal variability.


Assuntos
Metilação de DNA , Hevea , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Produtos Agrícolas/genética , Hevea/genética , Plântula/genética , Transplante Heterólogo , Árvores/genética
13.
BMC Genomics ; 23(1): 178, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35246041

RESUMO

BACKGROUND: Lipid droplets (LDs) present in land plants serve as an essential energy and carbon reserve for seed germination and seedling development. Oleosins, the most abundant structural proteins of LDs, comprise a small family involved in LD formation, stabilization and degradation. Despite their importance, our knowledge on oleosins is still poor in Euphorbiaceae, a large plant family that contains several important oil-bearing species. RESULTS: To uncover lineage-specific evolution of oleosin genes in Euphorbiaceae, in this study, we performed a genome-wide identification and comprehensive comparison of the oleosin family in Euphorbiaceae species with available genome sequences, i.e. castor bean (Ricinus communis), physic nut (Jatropha curcas), tung tree (Vernicia fordii), Mercurialis annua, cassava (Manihot esculenta) and rubber tree (Hevea brasiliensis), and a number of five, five, five, five, eight and eight members were found, respectively. Synteny analysis revealed one-to-one collinear relationship of oleosin genes between the former four (i.e. castor bean, physic nut, tung tree and M. annua) as well as latter two species (i.e. cassava and rubber tree), whereas one-to-one and one-to-two collinear relationships were observed between physic nut and cassava, reflecting the occurrence of one recent whole-genome duplication (WGD) in the last common ancestor of cassava and rubber tree. The presence of five ortholog groups representing three previously defined clades (i.e. U, SL and SH) dates back at least to the Malpighiales ancestor, because they are also conserved in poplar (Populus trichocarpa), a tree having experienced one Salicaceae-specific recent WGD. As observed in poplar, WGD was shown to be the main driver for the family expansion in both cassava and rubber tree. Nevertheless, same retention patterns of WGD-derived duplicates observed in cassava and rubber tree are somewhat different from that of poplar, though certain homologous fragments are still present in rubber tree. Further transcriptional profiling revealed an apparent seed-predominant expression pattern of oleosin genes in physic nut, castor bean and rubber tree. Moreover, structure and expression divergence of paralogous pairs were also observed in both cassava and rubber tree. CONCLUSION: Comparative genomics analysis of oleosin genes reported in this study improved our knowledge on lineage-specific family evolution in Euphorbiaceae, which also provides valuable information for further functional analysis and utilization of key members and their promoters.


Assuntos
Euphorbiaceae , Hevea , Euphorbiaceae/genética , Genoma de Planta , Genômica , Hevea/genética , Filogenia , Proteínas de Plantas/genética
14.
Biochem Genet ; 60(6): 2171-2199, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35296963

RESUMO

Scarcity of functional genetic markers associated with candidate genes (CGs) is a serious constraint for marker-assisted selection in the natural rubber producing tree, Hevea brasiliensis. In order to develop markers associated with rubber yield, five CGs involved in latex biosynthesis were characterized from 16 popular Hevea varieties. Novel SNPs and indels were identified and developed into markers using simple genotyping techniques like allele-specific PCR, CAPS, etc. A progeny population was genotyped using these markers to validate them, to understand their segregation pattern and to map them to a genetic linkage map. Parent-specific maps were constructed using pseudo-test cross strategy with the help of additional markers. The sequence structure information generated will be useful for future studies on gene mapping, functional relevance of coding SNPs and evolution of rubber biosynthesis genes in Hevea. Concurrently, the markers developed may serve as powerful tools for yield-based selection and for genetic diversity and pedigree studies in Hevea. Above all, the marker assays designed for genotyping could be economically carried out in any laboratory having basic molecular biology infrastructure and expertise.


Assuntos
Hevea , Hevea/genética , Hevea/metabolismo , Látex/metabolismo , Borracha/metabolismo , Vias Biossintéticas , Marcadores Genéticos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
Phytopathology ; 112(7): 1524-1536, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35238604

RESUMO

Cassiicolin (Cas), a toxin produced by Corynespora cassiicola, is responsible for Corynespora leaf fall disease in susceptible rubber trees. Currently, the molecular mechanisms of the cytotoxicity of Cas and its host selectivity have not been fully elucidated. Here, we analyzed the binding of Cas1 and Cas2 to membranes consisting of different plant lipids and their membrane disruption activities. Using high-speed atomic force microscopy and confocal microscopy, we reveal that the binding and disruption activities of Cas1 and Cas2 on lipid membranes are strongly dependent on the specific plant lipids. The negative phospholipids, glycerolipids, and sterols are more sensitive to membrane damage caused by Cas1 and Cas2 than neutral phospholipids and betaine lipids. Mature Cas1 and Cas2 play an essential role in causing membrane disruption. Cytotoxicity tests on rubber leaves of Rubber Research Institute of Vietnam (RRIV) 1, RRIV 4, and Prang Besar (PB) 255 clones suggest that the toxins cause necrosis of rubber leaves, except for the strong resistance of PB 255 against Cas2. Cryogenic scanning electron microscopy analyses of necrotic leaf tissues treated with Cas1 confirm that cytoplasmic membranes are vulnerable to the toxin. Thus, the host selectivity of Cas toxin is attained by the lipid-dependent binding activity of Cas to the membrane, and the cytotoxicity of Cas arises from its ability to form biofilm-like structures and to disrupt specific membranes.


Assuntos
Proteínas Associadas a CRISPR , Hevea , Lipídeos , Doenças das Plantas , Folhas de Planta/metabolismo , Borracha
16.
Braz J Microbiol ; 53(2): 857-872, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35247168

RESUMO

Plants of the genus Hevea present a great diversity of endophytic fungal species, which can provide bioactive compounds and enzymes for biotechnological use, and antagonist agents for plant disease biological control. The diversity of endophytic fungi associated with leaves of Hevea spp. clones in western Amazonia was explored using cultivation-based techniques, combined with the sequencing of the ITS rRNA-region. A total of 269 isolates were obtained, and phylogenetic analysis showed that they belong to 47 putative species, of which 24 species were unambiguous. The phylum Ascomycota was the most abundant (95.4%), with predominance of the genera Colletotrichum and Diaporthe, followed by the phylum Basidiomycota (4.6%), with abundance of the genera Trametes and Phanerochaete. Endophytic composition was influenced by the clones, with few species shared among them, and the greatest diversity was found in clone C44 (richness: 26, Shannon: 14,15, Simpson: 9.11). The potential for biocontrol and enzymatic production of endophytes has been investigated. In dual culture tests, 95% of the isolates showed inhibitory activity against C. gloeosporioides, and 84% against C. cassiicola. Efficient inhibition was obtained with isolates HEV158C and HEV255M (Cophinforma atrovirens and Polyporales sp. 2) for C. gloeosporioides, and HEV1A and HEV8B (Phanerochaete sp. 3 and Diaporthe sp. 4) for C. cassiicola. The endophytic isolates were positive for lipase (69.6%), amylase (67.6%), cellulase (33.3%), and protease (20.6%). The enzyme index ≥ 2 was found for amylase and lipase. The isolates obtained from rubber trees showed good antimicrobial and enzymatic potential, which can be tested in the future for use in the industry, and in the control of plant pathogens.


Assuntos
Hevea , Amilases , Biodiversidade , Endófitos , Fungos , Lipase , Filogenia , Plantas , Trametes
17.
Sci Rep ; 12(1): 3734, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260628

RESUMO

Natural rubber of the Para rubber tree (Hevea brasiliensis) is synthesized as a result of prenyltransferase activity. The proteins HRT1, HRT2, and HRBP have been identified as candidate components of the rubber biosynthetic machinery. To clarify the contribution of these proteins to prenyltransferase activity, we established a cell-free translation system for nanodisc-based protein reconstitution and measured the enzyme activity of the protein-nanodisc complexes. Co-expression of HRT1 and HRBP in the presence of nanodiscs yielded marked polyisoprene synthesis activity. By contrast, neither HRT1, HRT2, or HRBP alone nor a complex of HRT2 and HRBP manifested such activity. Similar analysis of guayule (Parthenium argentatum) proteins revealed that three HRT1 homologs (PaCPT1-3) manifested prenyltransferase activity only when co-expressed with PaCBP, the homolog of HRBP. Our results thus indicate that two heterologous subunits form the core prenyltransferase of the rubber biosynthetic machinery. A recently developed structure modeling program predicted the structure of such heterodimer complexes including HRT1/HRBP and PaCPT2/PaCBP. HRT and PaCPT proteins were also found to possess affinity for a lipid membrane in the absence of HRBP or PaCBP, and structure modeling implicated an amphipathic α-helical domain of HRT1 and PaCPT2 in membrane binding of these proteins.


Assuntos
Asteraceae , Dimetilaliltranstransferase , Hevea , Asteraceae/metabolismo , Hevea/metabolismo , Proteínas de Plantas/metabolismo , Borracha/metabolismo
18.
Arch Virol ; 167(3): 965-968, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35112201

RESUMO

Here, we report the complete genome sequence and organization of a novel virus detected in rubber trees (Hevea brasiliensis). Because the infected plants were asymptomatic, this virus was tentatively named "rubber tree latent virus 1" (RTLV1). The full genome of RTLV1 is 9,422 nt in length and contains three open reading frames with a 157-nt 5' untranslated region (UTR) and a 316-nt 3' UTR. The replicase shares the highest amino acid (aa) sequence identity (32.62%), with only 31% query coverage, with the replicase of Hubei virga-like virus 11. Phylogenetic analysis based on the aa sequence of ORF1 showed that RTLV1 clustered with unclassified members of the family Virgaviridae in a clade that was not closely related to any genus in this family.


Assuntos
Hevea , Vírus de RNA , Genoma Viral , Fases de Leitura Aberta , Filogenia , Vírus de RNA/genética , RNA Viral/genética , Análise de Sequência de DNA
19.
Rev Alerg Mex ; 69 Suppl 1: s55-s68, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34998311

RESUMO

Latex allergy is a major problem worldwide due to both the severity of the symptomatology it produces and the risk groups that are exposed to it. Complete avoidance is difficult, if not impossible, due to its ubiquity. Natural rubber latex (NRL) is a natural polymer that is released by the Hevea brasiliensis (Hev b) tree, which functions as a protective sealant. It is currently used for the manufacture of health-care products such as tube caps, pistons, masks, and cannulas. The purpose of this review is to highlight the epidemiological, clinical, and diagnostic aspects of NRL allergy, and to conduct a review of the literature on its management through a bibliographic search of articles in databases such as PubMed, Cochrane, UpToDate, and Google Scholar, up to September 2021. About 121 articles were reviewed, of which 76 were used as a reference. We concluded that latex allergy is an entity for which its treatment, even nowadays, is avoidance, despite having a worldwide prevalence of 4.3 % and representing a surgical complication in about 20 % of surgeries with an anaphylactic reaction and a mortality rate that can reach 9 %. The only treatment that could modify the evolution of this disease is immunotherapy, but there are no standardized extracts yet and it has not been possible to determine the safest and most effective way to apply it.


La alergia al látex es un problema importante en el mundo debido a la gravedad de la sintomatología que produce y a los grupos de riesgo expuestos. La evitación completa es difícil, casi imposible, dada su ubicuidad. El látex de caucho natural (LCN) es un polímero secretado por el árbol Hevea brasiliensis (Hev b), que funciona como sellador protector. Actualmente se usa para fabricar productos para el cuidado de la salud como tapones para tubos, pistones, mascarillas y cánulas. El objetivo de esta revisión es resaltar los aspectos epidemiológicos, clínicos y diagnósticos de la alergia al LCN, y realizar una revisión de la literatura sobre su manejo, mediante una búsqueda bibliográfica de artículos en bases de datos como PubMed, Cochrane, UpToDate y Google Académico, hasta septiembre del 2021. Se revisaron aproximadamente 121 artículos, de los cuales se utilizaron 76 como referencia. Concluimos que la alergia al látex es una entidad cuyo tratamiento aún hoy en día es la evitación, a pesar de tener una prevalencia mundial de 4.3 % y representar una complicación quirúrgica de cerca de 20 % de las cirugías con una reacción anafiláctica y una mortalidad que puede llegar a 9 %. El único tratamiento que podría modificar la evolución de esta enfermedad es la inmunoterapia, pero aún no se cuenta con extractos estandarizados y no se ha podido determinar la vía más segura y efectiva.


Assuntos
Hevea , Hipersensibilidade ao Látex , Alérgenos , Humanos , Hipersensibilidade ao Látex/diagnóstico , Hipersensibilidade ao Látex/epidemiologia , Hipersensibilidade ao Látex/terapia , Prevalência , Borracha
20.
Sci Rep ; 12(1): 480, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013381

RESUMO

The antioxidants used in the food industry are essential to inhibit the formation of free radicals, preserving the existing properties in the different matrices. However, the insecurity of the synthetic antioxidants regarding human health propels search for natural substrates with potential antioxidant activity as an alternative to synthetic compounds. In this way, the work had as objective obtaining extracts from the seed pomace of the Hevea brasiliensis (rubber tree), relating the contents of flavonoids and total phenols in the application as an antioxidant. The methodology consisted of the extraction using four solvents, varying extractive methods, time, and seed concentrations. The antioxidant activity in vitro was evaluated by capturing the DPPH (2,2-diphenyl-1-picryl-hydrazil) radical. The optimized results demonstrate that the aqueous extracts produced in the Soxhlet in the concentrations of 85 g L-1 and retention time of 4 h reached 37.73 ± 1.69% in the antioxidant tests of the free radical DPPH capture, 1405.15 mg EAC 100 g-1 in the quantification of phenolic compounds and 223.34 mg 100 g-1 of total flavonoids. Thus, this work may contribute to the realization of studies and future research for characterization and identification concerning which phenolic compounds and flavonoids attribute the antioxidant characteristic to the extracts produced, enabling the discovery of products with high added value in the production chain. In addition, because the water used as a solvent showed greater antioxidant potential between the extracts, the non-toxic and environmentally friendly character is highlighted, allowing a wide variety of applications in the food industry.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Hevea/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Radicais Livres/química , Sementes/química , Solventes/química , Resíduos/análise , Água/química
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