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Aims: This study aimed to optimize the extraction of flavonoids and antioxidants from Phalaenopsis leaves by using solvent mixtures. Method: The total flavonoid content (TFC) and antioxidant activity were evaluated using the colorimetric method and ferric-reducing antioxidant power (FRAP), respectively. Maceration extracts from fresh leaves were used for the analysis. The study used the Design Expert 13.0 program to optimize the solvents (water, acetone, and methanol) and their combined ratio. Result: The results showed that 100% acetone was the best solvent for both responses, with a desirability value of 0.884, TFC of 0.434 mg QE/g fresh weight (FW) and FRAP of 713.53 µmol TE/g FW. Screening of the most potent Phalaenopsis genotypes for obtaining the most active leaf extract showed that P. amboinensis and P. pantherina were the best genotypes for TFC (0.786-0.797 mg QE/g FW) and FRAP activity (862.25-891.48 µmol TE/g FW). Conclusion: This study demonstrates an easy and useful way to obtain flavonoids and antioxidants from Phalaenopsis materials that can be used in the flower-based industry to make new functional ingredients.
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Phalaenopsis aphrodite can be induced to initiate spike growth and flowering by exposure to low ambient temperatures. However, the factors and mechanisms responsible for spike initiation in P. aphrodite remain largely unknown. In this study, we show that a repressor Flowing Locus T-like (FTL) gene, FTL, can act as a negative regulator of spike initiation in P. aphrodite. The mRNA transcripts of PaFTL are consistently high during high ambient temperature, thereby preventing premature spike initiation. However, during low ambient temperature, PaFTL expression falls while FT expression increases, allowing for spike initiation. Knock-down of PaFTL expression through virus-inducing gene silencing promoted spike initiation at 30/28°C. Moreover, PaFTL interacts with FLOWERING LOCUS D in a similar manner to FT to regulate downstream flowering initiation genes. Transgenic P. aphrodite plants exhibiting high expression of PaFTL do not undergo spike initiation, even when exposed to low ambient temperatures. These findings shed light on the flowering mechanisms in Phalaenopsis and provide new insights into how perennial plants govern spike initiation in response to temperature cues.
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Orchidaceae , Temperatura , Orchidaceae/metabolismo , Flores/metabolismo , Frío , Regulación de la Expresión Génica de las PlantasRESUMEN
Salinity, drought and low temperature are major environmental factors that adversely affect crop productivity worldwide. In this study we adopted an activation tagging approach to identify salt tolerant mutants of Arabidopsis. Thousands of tagged Arabidopsis lines were screened to obtain several potential mutant lines resistant to 150 mM NaCl. Transcript analysis of a salt-stress tolerance 1 (sst1) mutant line indicated activation of AtMSRB5 and AtMSRB6 which encode methionine sulfoxide reductases. Overexpression of AtMSRB5 in Arabidopsis (B5OX) showed a similar salt tolerant phenotype. Furthermore, biochemical analysis indicated stability of the membrane protein, H+-ATPase 2 (AHA2) through regulation of Na+/K+ homeostasis which may be involved in a stress tolerance mechanism. Similarly, overexpression of AtMSRB5 in transgenic rice demonstrated a salt tolerant phenotype via the modulation of Na+/K+ homeostasis without a yield drag under salt and oxidative stress conditions.
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<b>Background and Objective:</b> <i>Celosia cristata</i> L. is an ornamental plant that has the potency to be developed as a medicinal plant. The mutation breeding of <i>C. cristata</i> targets the increase of biochemical compounds that are potential as antioxidants. This study aimed to evaluate the phenolic and flavonoid contents and antioxidant activity of the putative mutants of <i>C. cristata</i> in the M1 generation. <b>Materials and Methods:</b> The samples used in this study were flowers and seeds. Induced mutation, using ethyl methane sulphonate (EMS) was used to obtain M1 generation of putative mutants and twelve putative mutants were selected for polyphenol contents analysis composed of total phenolic (TPC), total flavonoid (TFC) and antioxidant activities analysis using two approaches, i.e., 2,2-diphenyl picrylhydrazyl (DPPH) method and ferric reducing antioxidant power (FRAP). <b>Results:</b> This study showed that total phenolics were varied from 11.73-18.06 mg GAE g<sup></sup><sup>1</sup> DW and total flavonoids were varied from 2.34-3.11 mg QE g<sup></sup><sup>1</sup> DW. Meanwhile, the antioxidant activity gain using the DPPH method ranged from 16.43-19.02 µmol TE g<sup></sup><sup>1</sup> DW and the FRAP method ranged from 40.72-59.61 µmol TE g<sup></sup><sup>1</sup> DW. The clustering analysis results formed three clusters with two clusters consisting of potential mutants with higher biochemical content and antioxidant capacities. It was found that total phenolic and flavonoids highly correlated with the antioxidant FRAP. <b>Conclusion:</b> Induced mutation using EMS can increase the diversity of biochemical characters and antioxidant activity of <i>C. cristata</i> and provide potential genetic material with higher chemical content for further development.
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Antioxidantes , Celosia , Antioxidantes/farmacología , Metanosulfonato de Etilo , Flavonoides/química , Metano , Fenoles/química , FitomejoramientoRESUMEN
BACKGROUND: The development of basal stem rot (BSR) disease in oil palm is associated with lignin during vegetative growth and salicylic acid (SA) biosynthesis. The increase in the lignin content, SA accumulation, growth, and root biomass could indicate the resistance of oil palm seedlings to BSR disease. Therefore, although there are many studies on the interactions between the Ganoderma boninense and oil palm, research on evaluation of physiological processes, biochemistry, and molecules occurring during early internal symptoms of BSR in roots of oil palm (Elaeis guineensis Jacq.) are essential. RESULTS: Ganoderma boninense inoculation indicated that C01, C02, and C05 seedlings were susceptible, while the other three seedlings, C03, C07, and C08, were resistant based on Ganoderma Disease Index (GDI). Infection by G. boninense in the most susceptible seedlings C05 reduced fresh weight of roots (FW) by 9.0%, and lignin content by 10.9%. The most resistant seedlings C08 were reduced by only 8.4%, and 0.2% regarding their fresh weight and lignin content, respectively. BSR disease induced SA accumulation in the most susceptible C08 and decreased peroxidase (PRX) enzyme (EC 1.11.1.7) activities in root tissues of oil palm seedlings except C07 and C08 where PRX activities remained high in the 4 months after planting. Infection with G. boninense also increased glutathione S-transferase U19-like (EgGSTU19) gene expression in the root tissues of susceptible seedlings, while laccase-24 (EgLCC24) gene expression was associated with resistance against BSR disease. Based on the relative expression of twelve genes, two genes are categorized as receptors (EgWAKL5, EgMIK1), two genes as biosynthesis signal transduction compound (EgOPR5, EgACO1), five genes as defense responses (EgROMT, EgSOT12, EgLCC24, EgGLT3, EgGSTU19), and one gene as trans-resveratrol di-O-methyltransferase-like (EgRNaseIII) predicted related to BSR infection. While two other genes remain unknown (EgUnk1, EgUnk2). CONCLUSIONS: Ganoderma infection-induced SA accumulation and lignification in resistant accessions promote the seedlings root biomass. Oil palm seedlings have a synergistic physical, biochemical, and molecular defense mechanism to the BSR disease. The utilization of nucleotide-based molecular markers using EgLCC24 gene is able to detect resistant oil palm seedlings to G. boninense.
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Arecaceae , Ganoderma , Arecaceae/genética , Arecaceae/metabolismo , Ganoderma/fisiología , Enfermedades de las Plantas/genética , Plantones/genéticaRESUMEN
BACKGROUND: Identifying non-invasive and reliable blood-derived biomarkers for early detection of acute cellular rejection in heart transplant recipients is of great importance in clinical practice. MicroRNAs are small molecules found to be stable in serum and their expression patterns reflect both physiological and underlying pathological conditions in human. METHODS: We compared a group of heart transplant recipients with histologically-verified acute cellular rejection (ACR, n = 26) with a control group of heart transplant recipients without allograft rejection (NR, n = 37) by assessing the levels of a select set of microRNAs in serum specimens. RESULTS: The levels of seven microRNAs, miR-142-3p, miR-101-3p, miR-424-5p, miR-27a-3p, miR-144-3p, miR-339-3p and miR-326 were significantly higher in ACR group compared to the control group and could discriminate between patients with and without allograft rejection. MiR-142-3p and miR-101-3p had the best diagnostic test performance among the microRNAs tested. Serum levels of miR-142-3p and miR-101-3p were independent of calcineurin inhibitor levels, as measured by tacrolimus and cyclosporin; kidney function, as measured by creatinine level, and general inflammation state, as measured by CRP level. CONCLUSION: This study demonstrated two microRNAs, miR-142-3p and miR-101-3p, that could be relevant as non-invasive diagnostic tools for identifying heart transplant patients with acute cellular rejection.
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Rechazo de Injerto/sangre , Rechazo de Injerto/diagnóstico , Trasplante de Corazón , MicroARNs/sangre , Proteínas Adaptadoras Transductoras de Señales/sangre , Proteínas Adaptadoras Transductoras de Señales/genética , Adulto , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Creatinina/sangre , Ciclosporina/sangre , Femenino , Regulación de la Expresión Génica , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Transducción de Señal , Tacrolimus/sangreRESUMEN
AIMS: Exosome-mediated microRNA transfer is a recently discovered mode of cell-to-cell communication, in which microRNAs act as paracrine molecules, exerting their regulatory effects in recipient cells. T cells and endothelial cells are two main players in the mechanism of acute cellular cardiac rejection. The aim of this study was to investigate the role of exosomal microRNAs in the crosstalk between T cells and endothelial cells and its implications for the molecular mechanisms that drive acute cellular rejection in heart transplantation. METHODS AND RESULTS: Exosomes isolated from serum samples of heart transplant patients with and without acute cardiac allograft rejection were profiled and showed enrichment of miR-142-3p, miR-92a-3p, miR-339-3p and miR-21-5p. Treatment of endothelial cells with the respected serum exosomes resulted the increased of miR-142-3p level in endothelial cells. Using T cells isolated from healthy donors and activated with either anti-CD3/CD28 antibody or IL-2/PHA, we could show that miR-142-3p is released from activated cells, is contained in exosomes and can be transferred to human vascular endothelial cells in vitro. Transcriptome analysis of endothelial cells treated with activated T cell supernatant with or without exosomes was used to identify mRNA targets of transferred miR-142-3-p. Overexpression of miR-142-3p in endothelial cells resulted in a significant down-regulation of RAB11FIP2, and interaction of miR-142-3p with its predicted target site was confirmed with a reporter assay. Moreover, treatment of endothelial cells with serum exosomes from heart transplant patients with acute cellular rejection resulted in down-regulation of RAB11FIP2 expression and increase in vascular endothelial permeability. CONCLUSION: We have identified a novel mechanism whereby miR-142-3p, a microRNA enriched in exosomes during acute cellular rejection, is transferred to endothelial cells and compromises endothelial barrier function via down-regulation of RAB11FIP2. This study sheds new light on the interaction between host immune system and cardiac allograft endothelium during acute cellular rejection.