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Robusta coffee blossom honey stands as a key regional product in Dak Lak province, Vietnam. Despite its significance, there exists a dearth of scientific data for assessing its quality. This study aims to fill this gap by characterizing the physicochemical properties and biological activities of coffee blossom honeys from three distinct sub-regions within Dak Lak province, Vietnam. These activities include ferric reducing power (FRP), DPPH and ABTS radical scavenging, as well as tyrosinase inhibitory activities. Moreover, the study compares these honey samples with other popular varieties in Vietnam, such as Lychee and Longan honeys. The physicochemical parameters of the honey samples meet the standards set by Codex Alimentarius 2001. Through UPLC analysis, eleven compounds were identified, with caffeine serving as a marker for coffee honey. Furthermore, by employing multiple factor analysis (MFA), it was observed that certain physicochemical properties correlate positively with tyrosinase inhibitory, DPPH, ABTS free radicals scavenging activities, and FRP. Notably, tyrosinase inhibitory activity exhibited a positive correlation with antioxidant activity. These findings underscore the high quality of Coffea robusta honey, showcasing its potent antioxidant and tyrosinase inhibitory activities.
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Antioxidantes , Inhibidores Enzimáticos , Miel , Monofenol Monooxigenasa , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Benzotiazoles/antagonistas & inhibidores , Benzotiazoles/química , Compuestos de Bifenilo/antagonistas & inhibidores , Café/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Flores/química , Miel/análisis , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Picratos/antagonistas & inhibidores , Ácidos Sulfónicos/antagonistas & inhibidores , VietnamRESUMEN
BACKGROUND: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has rapidly spread over the world and caused tremendous impacts on global health. Understanding the mechanism responsible for the spread of this pathogen and the impact of specific factors, such as human mobility, will help authorities to tailor interventions for future SARS-CoV-2 waves or newly emerging airborne infections. In this study, we aim to analyze the spatio-temporal transmission of SARS-CoV-2 in Belgium at municipality level between January and December 2021 and explore the effect of different levels of human travel on disease incidence through the use of counterfactual scenarios. METHODS: We applied the endemic-epidemic modelling framework, in which the disease incidence decomposes into endemic, autoregressive and neighbourhood components. The spatial dependencies among areas are adjusted based on actual connectivity through mobile network data. We also took into account other important factors such as international mobility, vaccination coverage, population size and the stringency of restriction measures. RESULTS: The results demonstrate the aggravating effect of international travel on the incidence, and simulated counterfactual scenarios further stress the alleviating impact of a reduction in national and international travel on epidemic growth. It is also clear that local transmission contributed the most during 2021, and municipalities with a larger population tended to attract a higher number of cases from neighboring areas. CONCLUSIONS: Although transmission between municipalities was observed, local transmission was dominant. We highlight the positive association between the mobility data and the infection spread over time. Our study provides insight to assist health authorities in decision-making, particularly when the disease is airborne and therefore likely influenced by human movement.
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COVID-19 , Epidemias , Humanos , SARS-CoV-2 , COVID-19/epidemiología , Bélgica/epidemiología , ViajeRESUMEN
AIMS: This study focused on the isolation and characterization of chitinolytic bacteria from Yok Don National Park, Vietnam for future studies regarding biofertilizers and biocontrol agents. METHODS AND RESULTS: Chitinolytic bacteria were isolated from soils and chitin flakes soaked in river water at the National Park. On the basis of the halo zones caused by colloidal chitin degradation and colony morphologies, 12 chitinolytic strains were chosen from 15 700 isolates for various examinations. Findings from 16S rDNA analysis indicated that among these strains, 10 could be identified as different species, and the remaining 2 showed less identity to known species and genera. The 12 bacteria possess numerous properties concerning plant growth promotion and/or phytopathogenic biocontrol. Paenibacillus chitinolyticus YSY-3.1, which exhibited the highest chitinase activity and remarkable properties for plant growth, was chosen for sequencing and draft genome analysis. The results showed that the genome is 6571 781 bp in length with 6194 coding sequences, 52.2% G + C, and 96.53% ANI value. It harbors the chitinolytic system comprising 22 enzymes. Among these enzymes, PcChiQ has a loop structure different from that of known family 19 chitinases, PcChiA contains two GH18 catalytic domains rarely found in microorganisms, and PcChiF contains three GH18 catalytic domains that have never been reported. CONCLUSIONS: The 12 identified chitinolytic bacteria exhibit great potential for further studies on plant growth-promoting and/or biocontrol properties. Among these bacteria, two strains might be good candidates for next examinations concerning novel species and/or genera, and strain YSY-3.1 could possess a novel chitinolytic system.
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Quitinasas , Parques Recreativos , Vietnam , Bacterias/genética , Bacterias/metabolismo , Quitinasas/genética , Quitinasas/metabolismo , Quitina/química , Quitina/metabolismoRESUMEN
Multi-drug resistance to antibiotics represents a growing challenge in treating infectious diseases. Outside the hospital, bacteria with the multi-drug resistance (MDR) phenotype have an increased prevalence in anthropized environments, thus implying that chemical stresses, such as metals, hydrocarbons, organic compounds, etc., are the source of such resistance. There is a developing hypothesis regarding the role of metal contamination in terrestrial and aquatic environments as a selective agent in the proliferation of antibiotic resistance caused by the co-selection of antibiotic and metal resistance genes carried by transmissible plasmids and/or associated with transposons. Efflux pumps are also known to be involved in either antibiotic or metal resistance. In order to deal with these situations, microorganisms use an effective strategy that includes a range of expressions based on biochemical and genetic mechanisms. The data from numerous studies suggest that heavy metal contamination could affect the dissemination of antibiotic-resistant genes. Environmental pollution caused by anthropogenic activities could lead to mutagenesis based on the synergy between antibiotic efficacy and the acquired resistance mechanism under stressors. Moreover, the acquired resistance includes plasmid-encoded specific efflux pumps. Soil microbiomes have been reported as reservoirs of resistance genes that are available for exchange with pathogenic bacteria. Importantly, metal-contaminated soil is a selective agent that proliferates antibiotic resistance through efflux pumps. Thus, the use of multi-drug efflux pump inhibitors (EPIs) originating from natural plants or synthetic compounds is a promising approach for restoring the efficacy of existing antibiotics, even though they face a lot of challenges.
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Bacterias , Metales Pesados , Farmacorresistencia Microbiana , Bacterias/genética , Bacterias/metabolismo , Plásmidos/genética , Metales Pesados/farmacología , Antibacterianos/farmacología , Antibacterianos/metabolismo , Farmacorresistencia Bacteriana Múltiple/genéticaRESUMEN
Measles resurged in Vietnam between 2018 and 2020, especially in the Southern region. The proportion of children with measles infection showed quite some variation at the provincial level. We applied a spatio-temporal endemic-epidemic modelling framework for age-stratified infectious disease counts using measles surveillance data collected in Southern Vietnam between 1 January 2018 and 30 June 2020. We found that disease transmission within age groups was greatest in young children aged 0-4 years whereas a relatively high between-group transmission was observed in older age groups (5-14 years, 15-24 years and 25+ years groups). At the provincial level, spatial transmission followed an age-dependent distance decay with measles spread mainly depending on local and neighbouring transmission. Our study helped to clarify the measles transmission dynamics in a more detailed fashion with respect to age strata, time and space. Findings from this study may help determine proper strategies in measles outbreak control including promotion of age-targeted intervention programmes in specific areas.
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Enfermedades Transmisibles , Epidemias , Sarampión , Anciano , Niño , Preescolar , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades/prevención & control , Humanos , Sarampión/prevención & control , Vietnam/epidemiologíaRESUMEN
BACKGROUND: Bacillus velezensis possesses numerous chitinolytic enzymes; however, not much is known about the role of its chitinase molecules. METHODS AND RESULTS: In this study, the chiA gene, which encodes a novel domain structure possessing family 18 chitinase from B. velezensis RB.IBE29, was expressed successfully in Escherichia coli BL21-CodonPlus (DE3)-RIPL using the pColdII expression vector. The recombinant protein, rBvChiA, was purified using the HisTrap FF column. Purified rBvChiA showed hydrolytic activity against insoluble chitin and bound to chitinous substrates. In addition, the purified recombinant enzyme displayed remarkable inhibition effects on the spore germination of Fusarium falciforme and the egg hatch of root-knot nematodes (Meloidogyne spp.), which are the main causes of black pepper diseases in the Central Highlands region, Vietnam. CONCLUSION: The current work results might enable further studies to develop novel chitinase A and strain RB.IBE29 as a natural fungicide and nematicide for sustainable black pepper production and other crops in the Central Highlands, Vietnam. This is the second report describing chitinase from B. velezensis based on the experimental data.
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Bacillus , Quitinasas , Secuencia de Aminoácidos , Bacillus/genética , Quitina/metabolismo , Quitinasas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismoRESUMEN
Bacillus velezensis RB.IBE29 is a potent biocontrol agent with high chitinase activity isolated from the rhizosphere of black pepper cultivated in the Central Highlands, Vietnam. Genome sequences revealed that this species possesses some GH18 chitinases and AA10 protein(s); however, these enzymes have not been experimentally characterized. In this work, three genes were identified from the genomic DNA of this bacterium and cloned in Escherichia coli. Sequence analysis exhibited that the ORF of chiA consists of 1,203 bp and encodes deduced 45.46 kDa-chitinase A of 400 aa. The domain structure of chitinase A is composed of a CBM 50 domain at the N-terminus and a catalytic domain at the C-terminus. The ORF of chiB includes 1,263 bp and encodes deduced 47.59 kDa-chitinase B of 420 aa. Chitinase B consists of two CBM50 domains at the N-terminus and a catalytic domain at the C-terminus. The ORF of lpmo10 is 621 bp and encodes a deduced 22.44 kDa-AA10 protein, BvLPMO10 of 206 aa. BvLPMO10 contains a signal peptide and an AA10 catalytic domain. Chitinases A and B were grouped into subfamily A of family 18 chitinases. Amino acid sequences in their catalytic domains lack aromatic residues (Trp, Phe, Tyr) probably involved in processivity and substrate binding compared with well-known bacterial GH18 chitinases. chiB was successfully expressed in E. coli. Purified rBvChiB degraded insoluble chitin and was responsible for inhibition of fungal spore-germination and egg hatching of plant-parasitic nematode. This is the first report describing the analysis of the chitinase system from B. velezensis.
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Quitinasas , Escherichia coli , Secuencia de Aminoácidos , Bacillus , Quitina , Quitinasas/genética , Quitinasas/metabolismo , Clonación Molecular , Escherichia coli/genéticaRESUMEN
Influenza burden estimates are essential to informing prevention and control policies. To complement recent influenza vaccine production capacity in Vietnam, we used acute respiratory infection (ARI) hospitalization data, severe acute respiratory infection (SARI) surveillance data, and provincial population data from 4 provinces representing Vietnam's major regions during 2014-2016 to calculate provincial and national influenza-associated ARI and SARI hospitalization rates. We determined the proportion of ARI admissions meeting the World Health Organization SARI case definition through medical record review. The mean influenza-associated hospitalization rates per 100,000 population were 218 (95% uncertainty interval [UI] 197-238) for ARI and 134 (95% UI 119-149) for SARI. Influenza-associated SARI hospitalization rates per 100,000 population were highest among children <5 years of age (1,123; 95% UI 946-1,301) and adults >65 years of age (207; 95% UI 186-227), underscoring the need for prevention and control measures, such as vaccination, in these at-risk populations.
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Vacunas contra la Influenza , Gripe Humana , Adulto , Anciano , Niño , Hospitalización , Humanos , Gripe Humana/epidemiología , Vigilancia de Guardia , Vietnam/epidemiologíaRESUMEN
Topological magnonic materials have attracted much interest because of the potential for dissipationless spintronic applications. Pyrochlore iridates are theoretically regarded as good candidates for designing topological magnon bands. However, experimental identification of topological magnon bands in pyrochlore iridates remains elusive. We explored this possibility in Y_{2}Ir_{2}O_{7} using Raman spectroscopy to measure both the single-magnon excitations and anomalous phonon shifts. From the single-magnon energies and tight-binding model calculations concerning the phonons, we determined the key parameters in the spin Hamiltonian. These confirm that Y_{2}Ir_{2}O_{7} hosts a nontrivial magnon band topology distinct from other pyrochlore iridate compounds. Our work demonstrates that pyrochlore iridates constitute a system in which the magnon band topology can be tailored and that Raman spectroscopy is a powerful technique to explore magnon band topology.
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Recently, microbial prodigiosin (PG) has received much attention due to its numerous beneficial applications. The aim of this study was to establish the bioprocessing of marine chitinous wastes (MCWs) for the cost-effective preparation of PG. Of the MCWs, demineralized shrimp shell powders (de-SSP) were found to be a potential source of carbon/nitrogen (C/N) for PG production by bacterial fermentation using Serratia marcescens strains. Further, PG scale-up production was investigated in a 15 L bioreactor system, and the highest yield (6200 mg/L) was achieved during fermentation using 5 L of a novel-designed culture broth that included 1.60% C/N sources (a de-SSP/casein ratio of 7/3), 0.02% K2SO4, and 0.05% K2HPO4, with an initial pH of 6-7. Fermentation was conducted in the dark at 27.5 °C for 8.0 h. This study was the first to report on the utilization of shrimp wastes for cost-effective, large-scale (5 L/pilot) PG production with high productivity (6200 mg/L) in a short cultivation time. The combination of 0.02% K2SO4 and 0.05% K2HPO4 was also found to be a novel salt composition that significantly enhanced PG yield. The red compound was purified and confirmed as PG after analyzing its HPLC profile, mass, and UV/vis spectra. The purified PG was then tested for its bioactivities and showed effective anticancer activities, moderated antioxidant activities, and novel anti-NO effects.
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Quitina/metabolismo , Prodigiosina/metabolismo , Agua de Mar , Animales , Reactores Biológicos , Crustáceos , Fermentación , Serratia marcescens/metabolismo , Espectrofotometría UltravioletaRESUMEN
BACKGROUND: Despite repeated outbreaks, in particular the devastating 2014-2016 epidemic, there is no effective treatment validated for patients with Ebola virus disease (EVD). Among the drug candidates is the broad-spectrum polymerase inhibitor favipiravir, which showed a good tolerance profile in patients with EVD (JIKI trial) but did not demonstrate a strong antiviral efficacy. In order to gain new insights into the antiviral efficacy of favipiravir and improve preparedness and public health management of future outbreaks, we assess the efficacy achieved by ascending doses of favipiravir in Ebola-virus-infected nonhuman primates (NHPs). METHODS AND FINDINGS: A total of 26 animals (Macaca fascicularis) were challenged intramuscularly at day 0 with 1,000 focus-forming units of Ebola virus Gabon 2001 strain and followed for 21 days (study termination). This included 13 animals left untreated and 13 treated with doses of 100, 150, and 180 mg/kg (N = 3, 5, and 5, respectively) favipiravir administered intravenously twice a day for 14 days, starting 2 days before infection. All animals left untreated or treated with 100 mg/kg died within 10 days post-infection, while animals receiving 150 and 180 mg/kg had extended survival (P < 0.001 and 0.001, respectively, compared to untreated animals), leading to a survival rate of 40% (2/5) and 60% (3/5), respectively, at day 21. Favipiravir inhibited viral replication (molecular and infectious viral loads) in a drug-concentration-dependent manner (P values < 0.001), and genomic deep sequencing analyses showed an increase in virus mutagenesis over time. These results allowed us to identify that plasma trough favipiravir concentrations greater than 70-80 µg/ml were associated with reduced viral loads, lower virus infectivity, and extended survival. These levels are higher than those found in the JIKI trial, where patients had median trough drug concentrations equal to 46 and 26 µg/ml at day 2 and day 4 post-treatment, respectively, and suggest that the dosing regimen in the JIKI trial was suboptimal. The environment of a biosafety level 4 laboratory introduces a number of limitations, in particular the difficulty of conducting blind studies and performing detailed pharmacological assessments. Further, the extrapolation of the results to patients with EVD is limited by the fact that the model is fully lethal and that treatment initiation in patients with EVD is most often initiated several days after infection, when symptoms and high levels of viral replication are already present. CONCLUSIONS: Our results suggest that favipiravir may be an effective antiviral drug against Ebola virus that relies on RNA chain termination and possibly error catastrophe. These results, together with previous data collected on tolerance and pharmacokinetics in both NHPs and humans, support a potential role for high doses of favipiravir for future human interventions.
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Amidas/farmacología , Amidas/farmacocinética , Antivirales/farmacología , Ebolavirus , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Pirazinas/farmacología , Pirazinas/farmacocinética , Animales , Relación Dosis-Respuesta a Droga , Femenino , Genoma Viral , Humanos , Macaca fascicularis , Mutagénesis , ARN/análisis , Factores de Tiempo , Investigación Biomédica Traslacional , Carga ViralRESUMEN
Favipiravir is an RNA polymerase inhibitor that showed strong antiviral efficacy in vitro and in small-animal models of several viruses responsible for hemorrhagic fever (HF), including Ebola virus. The aim of this work was to characterize the complex pharmacokinetics of favipiravir in nonhuman primates (NHPs) in order to guide future efficacy studies of favipiravir in large-animal models. Four different studies were conducted in 30 uninfected cynomolgus macaques of Chinese (n = 17) or Mauritian (n = 13) origin treated with intravenous favipiravir for 7 to 14 days with maintenance doses of 60 to 180 mg/kg of body weight twice a day (BID). A pharmacokinetic model was developed to predict the plasma concentrations obtained with different dosing regimens, and the model predictions were compared to the 50% effective concentration (EC50) of favipiravir against several viruses. Favipiravir pharmacokinetics were described by a model accounting for concentration-dependent aldehyde oxidase inhibition. The enzyme-dependent elimination rate increased over time and was higher in NHPs of Mauritian origin than in those of Chinese origin. Maintenance doses of 100 and 120 mg/kg BID in Chinese and Mauritian NHPs, respectively, are predicted to achieve median trough plasma free concentrations above the EC50 for Lassa and Marburg viruses until day 7. For Ebola virus, higher doses are required. After day 7, a 20% dose increase is needed to compensate for the increase in drug clearance over time. These results will help rationalize the choice of dosing regimens in future studies evaluating the antiviral effect of favipiravir in NHPs and support its development against a variety of HF viruses.
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Amidas/uso terapéutico , Antivirales/uso terapéutico , Fiebres Hemorrágicas Virales/tratamiento farmacológico , Pirazinas/uso terapéutico , Administración Intravenosa , Aldehído Oxidasa/metabolismo , Animales , Chlorocebus aethiops , Ebolavirus/efectos de los fármacos , Ebolavirus/patogenicidad , Fiebres Hemorrágicas Virales/virología , Primates , Células VeroRESUMEN
PURPOSE: In mixed models, the relative standard errors (RSE) and shrinkage of individual parameters can be predicted from the individual Bayesian information matrix (MBF). We proposed an approach accounting for data below the limit of quantification (LOQ) in MBF. METHODS: MBF is the sum of the expectation of the individual Fisher information (MIF) which can be evaluated by First-Order linearization and the inverse of random effect variance. We expressed the individual information as a weighted sum of predicted MIF for every possible design composing of measurements above and/or below LOQ. When evaluating MIF, we derived the likelihood expressed as the product of the likelihood of observed data and the probability for data to be below LOQ. The relevance of RSE and shrinkage predicted by MBF in absence or presence of data below LOQ were evaluated by simulations, using a pharmacokinetic/viral kinetic model defined by differential equations. RESULTS: Simulations showed good agreement between predicted and observed RSE and shrinkage in absence or presence of data below LOQ. We found that RSE and shrinkage increased with sparser designs and with data below LOQ. CONCLUSIONS: The proposed method based on MBF adequately predicted individual RSE and shrinkage, allowing for evaluation of a large number of scenarios without extensive simulations.
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Teorema de Bayes , Modelos Biológicos , Modelos Estadísticos , Biología Computacional , Simulación por Computador , Humanos , ProbabilidadRESUMEN
BACKGROUND: Dengue infection has various clinical manifestations, often with unpredictable clinical evolutions and outcomes. Several factors including nutritional status have been studied to find the relationship with dengue severity. However, the nutritional status had conflicting effects on the complication of dengue in some previous studies. Therefore, we conducted a systematic review and performed a meta-analysis to analyze the association between nutritional status and the outcome of dengue infection. METHODS: Eleven electronic databases and manual searching of reference lists were used to identify the relevant studies published before August 2013. At least two authors worked independently in every step to select eligible studies and extract data. Dengue severity in the included studies must be classified into three categories: dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). RESULTS: Thirteen articles that met the inclusion criteria came to final analysis. A meta-analysis using fixed- or random-effects models was conducted to calculate pooled odds ratios (OR) with corresponding 95 % confidence intervals. It has shown that there was no statistically significant association between DHF group and DSS group in malnutritional and overweight/obesity patients with OR: 1.17 (95 % CI: 0.99-1.39), 1.31 (0.91-1.88), respectively. A significantly inverse relation between DF and DHF groups of malnutritional patients was revealed (OR = 0.71, 95 % CI: 0.56-0.90). Our meta-analysis also indicated a statistically significant negative correlation between malnourished children with dengue virus infection and healthy children (OR = 0.46, 95 % CI: 0.3-0.70). When analyzing patients with normal nutrition status, we found out that there was a significantly negative relationship between DHF and DSS groups (0.87; 95 % CI: 0.77-0.99). Other comparisons of DSS with DF/DHF groups, DSS/DHF with DF groups, and DHF with DF groups in normal nutritional patients showed no significant correlation. However, the findings should be interpreted cautiously because all significant associations were lost after removing of the largest study. CONCLUSIONS: Results from previous studies failed to show any solid consistency regarding the association between the nutritional status and dengue infection. Consequently, the effects of nutritional status on dengue disease outcome has been controversial. Further studies are recommended to clarify the impact of nutritional status on dengue infection.
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Dengue/diagnóstico , Estado Nutricional , Bases de Datos Factuales , Dengue/patología , Dengue/virología , Virus del Dengue/aislamiento & purificación , Humanos , Desnutrición , Obesidad/patología , Oportunidad Relativa , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: To estimate the proportion of participants in clinical trials who understand different components of informed consent. METHODS: Relevant studies were identified by a systematic review of PubMed, Scopus and Google Scholar and by manually reviewing reference lists for publications up to October 2013. A meta-analysis of study results was performed using a random-effects model to take account of heterogeneity. FINDINGS: The analysis included 103 studies evaluating 135 cohorts of participants. The pooled proportion of participants who understood components of informed consent was 75.8% for freedom to withdraw at any time, 74.7% for the nature of study, 74.7% for the voluntary nature of participation, 74.0% for potential benefits, 69.6% for the study's purpose, 67.0% for potential risks and side-effects, 66.2% for confidentiality, 64.1% for the availability of alternative treatment if withdrawn, 62.9% for knowing that treatments were being compared, 53.3% for placebo and 52.1% for randomization. Most participants, 62.4%, had no therapeutic misconceptions and 54.9% could name at least one risk. Subgroup and meta-regression analyses identified covariates, such as age, educational level, critical illness, the study phase and location, that significantly affected understanding and indicated that the proportion of participants who understood informed consent had not increased over 30 years. CONCLUSION: The proportion of participants in clinical trials who understood different components of informed consent varied from 52.1% to 75.8%. Investigators could do more to help participants achieve a complete understanding.
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Comprensión , Consentimiento Informado/psicología , Sujetos de Investigación/psicología , Adulto , Ensayos Clínicos como Asunto , Femenino , Alfabetización en Salud , Humanos , Consentimiento Informado/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Adulto JovenRESUMEN
BACKGROUND: A multi-monocistronic synthetic vector was used to assemble multiple genes of a nucleotide diphosphate (NDP)-sugar biosynthetic pathway to construct robust genetic circuits for the production of valuable flavonoid glycosides in Escherichia coli. Characterized functional genes involved in the biosynthesis of uridine diphosphate (UDP)-glucose and thymidine diphosphate (TDP)-rhamnose from various microbial sources along with glucose facilitator diffusion protein (glf) and glucokinase (glk) from Zymomonas mobilis were assembled and overexpressed in a single synthetic multi-monocistronic operon. RESULTS: The newly generated NDP-sugars biosynthesis circuits along with regiospecific glycosyltransferases from plants were introduced in E. coli BL21 (DE3) to probe the bioconversion of fisetin, a medicinally important polyphenol produced by various plants. As a result, approximately 1.178 g of fisetin 3-O-glucoside and 1.026 g of fisetin 3-O-rhamnoside were produced in UDP-glucose and TDP-rhamnose biosynthesis systems respectively, after 48 h of incubation in 3 L fermentor while supplementing 0.9 g of fisetin. These yields of fisetin glycosides represent ~99% of bioconversion of exogenously supplemented fisetin. The systems were also found to be highly effective in bio-transforming other flavonols (quercetin, kaempferol, myricetin) into their respective glycosides, achieving over 95% substrate conversion. CONCLUSION: The construction of a synthetic expression vector for bacterial cell factory followed by subsequent re-direction of metabolic flux towards desirable products have always been revolutionized the biotechnological processes and technologies. This multi-monocistronic synthetic vector in a microbial platform is customizable to defined task and would certainly be useful for applications in producing and modifying such therapeutically valued plant secondary metabolites.
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Escherichia coli/metabolismo , Flavonoles/metabolismo , Glicósidos/metabolismo , Glicosiltransferasas/genéticaRESUMEN
The Cavendish banana (Musa cavendishii L.) is one of the main perennial crops grown in Dak Lak Province of Vietnam. However, data on the endophytic bacterial community of this plant are unknown. In this work, a representative sample, mixing from 5 root samples collected from five banana gardens (the Dwarf Cavendish cultivar) in Dak Lak, was used for analyzing the endophytic microbiome using 16S rRNA gene metabarcoding. Results showed that 5 phyla, 7 classes, 20 orders, 31 families, and 47 genera of endophytic bacteria were identified from the sample. Bacteria belonging to phylum Proteobacteria were the most predominant, with 72.64%, and functions involved in biosynthesis were the most abundant, with 75.35%, of the endophytic bacterial community. Data help to understand the endophytic bacterial community of the Cavendish banana cultivated in Dak Lak, Vietnam. These data can be useful for further experiments concerning relationships between the growth of the Cavendish banana and endophytic bacteria. This is the first report on the endophytic bacteria of the Cavendish banana cultivated in Dak Lak, Vietnam.
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Vietnam is currently one of the largest producers and exporters of cashew nuts in the world. Cashew (Anacardium occidentale L.) is one of the main industrial crops cultivated in Dak Lak Province of Vietnam. Comprehending the endophytic bacteria of this plant, a new biofertilizer for sustainable cashew nut production can be progressed. In this report, the cashew root sample was collected from cashew fields in 2021 in Dak Lak. The DNeasy Powersoil kit was used to extract the genomic DNA of endophytic bacteria from the root sample. The 16S rRNA genes (V1-V9 regions) were amplified by PCR, and libraries of amplicons were prepared using the Swift amplicon 16S plus ITS panel kit. The Illumina MiSeq platform was applied to sequence amplicon libraries using 16S rRNA metagenomics. Taxonomic analyses showed that Gammaproteobacteria (38.77 %) and Alphaproteobacteria (37.76 %) were the predominant classes among the endophytic bacteria. Functional analyses revealed that biosynthesis (72.78 %) was the primary function of the endophytic bacterial community. Raw sequences (Fastq files) have been deposited in Mendeley Data [1]. The obtained data provide insight into the endophytic bacterial community of cashews cultivated in Dak Lak Province of Vietnam. The data are valuable for further developing a new biofertilizer for cashew nut production using endophytic bacteria. Ours is the first report about endophytic bacterial communities of cashews cultivated in this province as well as the Central Highlands of Vietnam.
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Stretchable sensors have been widely investigated and developed for the purpose of human motion detection, touch sensors, and healthcare monitoring, typically converting mechanical/structural deformation into electrical signals. The viscoelastic strain of stretchable materials often results in nonlinear stress-strain characteristics over a broad range of strains, consequently making the stretchable sensors at the body joints less accurate in predicting and recognizing human gestures. Accurate recognition of human gestures can be further deteriorated by environmental changes such as temperature and humidity. Here, we demonstrated an environment-adaptable high stress-strain linearity (up to ε = 150%) and high-durability (>100,000 cycles) stretchable sensor conformally laminated onto the body joints for human gesture recognition. The serpentine configuration of our ionic liquid-based stretchable film enabled us to construct broad data sets of mechanical strain and temperature changes for machine learning-based gesture recognition. Signal recognition and training of distinct strains and environmental stimuli using a machine learning-based algorithm analysis successfully measured and predicted the joint motion in a temperature-changing environment with an accuracy of 92.86% (R-squared). Therefore, we believe that our serpentine-shaped ion gel-based stretchable sensor harmonized with machine-learning analysis will be a significant achievement toward environmentally adaptive and multianalyte sensing applications. Our proposed machine learning-enabled multisensor system may enable the development of future electronic devices such as wearable electronics, soft robotics, electronic skin, and human-machine interaction systems.
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Robótica , Dispositivos Electrónicos Vestibles , Humanos , Gestos , Movimiento (Física) , ElectrónicaRESUMEN
Citrus (Citrus nobilis L.) is one of the main fruit crops in Dak Lak Province of Vietnam; however, a dataset on the endophytic microbiome of this plant has yet to be discovered. This article presented the endophytic microbial dataset from roots of healthy Citrus nobilis L. collected in Dak Lak for the first time. We found that 4 kingdoms, 30 phyla, 58 classes, 125 orders, 242 families, 722 genera, and 1637 species of endophytic microorganisms were identified from the sample. Actinomycetota was shown to be the main phylum (64.36 %) and biosynthesis to be the most abundant function (55.64 %) of the endophytic microbial community. Data provided insights into the composition and functional diversity of the Citrus nobilis L. endophytic microbiome, especially novel microbial resources. They could be used for the next works towards applying the endophytic microbiome for sustainable citrus production.