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1.
Molecules ; 29(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38999144

RESUMO

This study assessed the nutritional profile of camellia oil through its fatty acid composition, highlighting its high oleic acid content (81.4%), followed by linoleic (7.99%) and palmitic acids (7.74%), demonstrating its excellence as an edible oil source. The impact of beeswax (BW) and glycerol monolaurate (GML) on camellia oil oleogels was investigated, revealing that increasing BW or GML concentrations enhanced hardness and springiness, with 10% BW oleogel exhibiting the highest hardness and springiness. FTIR results suggested that the structure of the oleogels was formed by interactions between molecules without altering the chemical composition. In biscuits, 10% BW oleogel provided superior crispness, expansion ratio, texture, and taste, whereas GML imparted a distinct odor. In sausages, no significant differences were observed in color, water retention, and pH between the control and replacement groups; however, the BW group scored higher than the GML group in the sensory evaluation. The findings suggest that the BW oleogel is an effective fat substitute in biscuits and sausages, promoting the application of camellia oil in food products.


Assuntos
Camellia , Lauratos , Monoglicerídeos , Compostos Orgânicos , Óleos de Plantas , Ceras , Camellia/química , Ceras/química , Óleos de Plantas/química , Lauratos/química , Compostos Orgânicos/química , Compostos Orgânicos/análise , Monoglicerídeos/química , Produtos da Carne/análise , Paladar , Ácidos Graxos/química , Ácidos Graxos/análise
2.
J Med Virol ; 94(8): 3820-3828, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35437759

RESUMO

Coxsackievirus A10 (CV-A10) is a major pathogen that causes hand, foot, and mouth disease. There are no effective therapeutic drugs for CV-A10 infection; therefore, CV-A10 vaccines should be developed. Previously, we isolated a CV-A10 strain (N25) that can be cultured on Vero cells. In this study, the N25 strain was plaque-purified three times from Vero cells, and three clones were selected for adaptive culture. The three clones of the 5th, 12th, and 19th generations were compared and analyzed in terms of viral titers, plaque morphology, pathogenicity in suckling mice, and nucleotide and amino acid sequences of the complete genome. The infectivity titers of the three clones (P2-P22) were maintained at 6.5-7.0 lgCCID50 /ml. The three clones began to proliferate at 6 h and peaked at 36 h; the corresponding CCID50 was in the range of 106.5 -106.875 /ml, which gradually decreased. The suckling mice in the challenged group exhibited clinical symptoms such as paralysis of the limbs, which gradually worsened until death. The inactivated vaccines prepared using the three clones efficiently induced antigen-specific serum antibodies in mice. There were eight nucleotide mutations in the three clones, which resulted in two and four amino acid substitutions in the VP3 and VP1 coding regions, respectively. The nucleotide and amino acid sequence homology between the three clones and N25 were 99.92%-100% and 99.78%-100%, respectively, indicating high genetic stability. Our findings provide a theoretical basis for screening CV-A10 vaccine candidate clones.


Assuntos
Enterovirus Humano A , Doença de Mão, Pé e Boca , Animais , Benzenoacetamidas , Chlorocebus aethiops , Células Clonais , Enterovirus Humano A/genética , Genótipo , Humanos , Camundongos , Nucleotídeos , Piperidonas , Células Vero
4.
Sci Total Environ ; 953: 175981, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39245382

RESUMO

According to the coupled influence of climate variation and anthropogenic activities, hydro-meteorological variables are hard to keep stationary in a changing environment. Consequently, the efficacy of traditional standardized drought indices, predicated upon the assumption of stationarity, has been called into question. In China, the challenge of drought monitoring and declaration is exacerbated by the need for multiple drought indices covering meteorological, agricultural, hydrological, and groundwater aspects, often lacking real-time availability. To address these challenges, we developed a framework for drought monitoring and assessment from a drought propagation perspective. Central to this is the Nonstationary Integrated Drought Index (NIDI), which integrates responses from meteorological, agricultural, hydrological, and groundwater droughts, accounting for climate change and anthropogenic influences. First, we analyse the process of drought propagation to select the suitable time scale standardized drought index. Subsequently, significant large-scale climatic indices are selected through linear and nonlinear correlation analyses to identify climate anomalies. Anthropogenic influences are assessed using indicators such as the Normalized Difference Vegetation Index (NDVI), Impervious Surface Ratio (ISR), and population density (POP). Nonstationary probability models are then developed for precipitation, soil moisture, runoff, and groundwater series, incorporating climatic and human-induced factors. Finally, the NIDI is calculated using a D-vine copula model, with parameter estimation and updating facilitated by a genetic algorithm, representing the temporal dependence structure among the variables. A case study in the Hulu River Basin of western China validated the NIDI. Results showed that the NIDI effectively accounts for nonstationary hydro-meteorological variables due to climate change and human activities, accurately reproducing their time-dependent structure. Compared to conventional indices like SPI, SSI, SRI, and SGI, the NIDI identifies more extreme drought events. In conclusion, the presented NIDI offers a more comprehensive approach to drought identification, providing valuable insights for accurate drought detection and effective drought-related policy-making.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32252277

RESUMO

The purpose of this study is to illustrate intrinsic correlations and their temporal evolution between hydro-meteorological elements by building three-element-composed system, including precipitation (P), runoff (R), air temperature (T), evaporation (pan evaporation, E), and sunshine duration (SD) in the Wuding River Basin (WRB) in Loess Plateau, China, and to provide regional experience to correlational research of global hydro-meteorological data. In analysis, detrended partial cross-correlation analysis (DPCCA) and temporal evolution of detrended partial-cross-correlation analysis (TDPCCA) were employed to demonstrate the intrinsic correlation, and detrended cross-correlation analysis (DCCA) coefficient was used as comparative method to serve for performance tests of DPCCA. In addition, a novel way was proposed to estimate the contribution of a variable to the change of correlation between other two variables, namely impact assessment of correlation change (IACC). The analysis results in the WRB indicated that (1) DPCCA can analyze the intrinsic correlations between two hydro-meteorological elements by removing potential influences of the relevant third one in a complex system, providing insights on interaction mechanisms among elements under changing environment; (2) the interaction among P, R, and E was most strong in all three-element-composed systems. In elements, there was an intrinsic and stable correlation between P and R, as well as E and T, not depending on time scales, while there were significant correlations on local time scales between other elements, i.e., P-E, R-E, P-T, P-SD, and E-SD, showing the correlation changed with time-scales; (3) TDPCCA drew and highlighted the intrinsic correlations at different time-scales and its dynamics characteristic between any two elements in the P-R-E system. The results of TDPCCA in the P-R-E system also demonstrate the nonstationary correlation and may give some experience for improving the data quality. When establishing a hydrological model, it is suitable to only use P, R, and E time series with significant intrinsic correlation for calibrating model. The IACC results showed that taking pan evaporation as the representation of climate change (barring P), the impacts of climate change on the non-stationary correlation of P and R was estimated quantitatively, illustrating the contribution of climate to the correlation variation was 30.9%, and that of underlying surface and direct human impact accounted for 69.1%.


Assuntos
Mudança Climática , Meteorologia , China , Monitoramento Ambiental , Humanos , Hidrologia , Rios
6.
PLoS One ; 15(11): e0238709, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33151946

RESUMO

Changes in precipitation patterns greatly impact regional drought/flood risk management and utilization of water resources. The main purpose of this paper was to investigate spatio-temporal variability of precipitation concentration in the transitional zone between Qinling Mountains (QDM), Guanzhong Plain (GZP) and the Loess Plateau (LPNS) in China, using monthly-scale precipitation concentration index (PCI) and daily-scale concentration index (CI) from daily rainfall records. The Mann-Kendall method was employed to illustrate the change in trend of PCI and CI, the Kriging interpolation method was adopted to measure spatial distribution, and the Wavelet transforms were used to explore their spatio-temporal correlation with the Arctic Oscillation (AO) & Western Pacific Subtropical High (WPSH) for revealing the potential attribution of precipitation concentration variation. Also, the regional implication of CI was investigated in the zone to provide local knowledge of the index application. Results showed that annual precipitation demonstrated a north-south increasing layered spatial distribution in the zone, representing a generally decreasing trend. The CI change generally exhibited a more significant decreasing trend than did PCI in LPNS and GZP due to AO slowly increasing over time, with a spatially weak layered or radial north-south decay, and an insignificant increasing trend in QDM impacted by the enhancing WPSH, with an obvious layered or radial spatial distribution. The spatiotemporal pattern of PCI variation represented similar characteristics in attribution with CI, but an inverse spatial distribution due to the phase difference (positive and negative effects) of AO and WPSH influencing seasonal precipitation. Regional analysis of CI showed that the CI value with over 0.62 indicated that approximately 80% of precipitation was contributed by 25% of the rainiest days in this zone. Fortunately, the area with this high CI has been getting smaller, implying a positive trend toward regional flash flood and debris flow control.


Assuntos
Inundações/estatística & dados numéricos , Chuva , China , Mudança Climática , Secas/estatística & dados numéricos , Ecossistema , Análise Espacial , Temperatura , Recursos Hídricos
7.
Appl Biochem Biotechnol ; 190(1): 73-89, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31301009

RESUMO

Curvulamine, a novel scaffold alkaloid with remarkable selective antibacterial activity, is produced by marine fungus Curvularia sp. IFB-Z10. However, its deep pharmaceutical research and application are severely restricted by the low yield, which needs to be solved urgently. The purpose of this study was to improve curvulamine production via precursors co-addition strategy and further reveal the regulation mechanism. In this work, the optimal precursors co-addition conditions were firstly obtained, and curvulamine production achieved 166.74 mg/L with the supply of 250 mg/L alanine and 200 mg/L proline at 60 h, which was 4.08 times that of control. It was observed that under alanine and proline stimulation, fungus exhibited the morphology of a small-diameter compact pellet. Furthermore, the organic acid levels in central carbon metabolism (CCM) were declined with precursors supplement. Besides, precursors also induced the critical biosynthetic gene transcriptions. The above findings collectively promoted curvulamine synthesis. Finally, Curvularia sp. IFB-Z10 fermentation process was successfully established by feeding alanine and proline at 0.021 g/L/h and 0.017 g/L/h rate from 60 to 72 h, and curvulamine production reached 133.58 mg/L in a 5-L bioreactor. The information acquired would facilitate the enhancement of curvulamine yield in submerged fermentation and the research on synthesis regulation of other alkaloids.


Assuntos
Alcaloides/biossíntese , Ascomicetos/metabolismo , Aminoácidos/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Reatores Biológicos , Metabolismo dos Carboidratos , Divisão Celular , Fermentação , Genes Fúngicos , Alcaloides Indólicos , Nitrogênio/metabolismo , Transcrição Gênica
8.
J Microbiol Biotechnol ; 29(4): 587-595, 2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-30786698

RESUMO

Pharmacological research on (CHA), a marine-derived quinazolinone alkaloid with significant cytotoxic activity, is restricted by low yields and is a problem that needs to be settled urgently. In this work, the selection of additional nitrogen sources and the optimization of additional concentrations and longer fermentation times using ammonium acetate, were investigated. CHA production was optimized to 62.1 mg/l with the addition of 50 mM ammonium acetate at 120 h of the fermentation in the shaker flask. This feeding strategy significantly increased 3- deoxy-arabino-heptulosonate-7-phosphate synthase activity and transcript levels of critical genes (laeA, dahp and trpC) in the shikimate pathway compared with the non-treatment group. In addition, the selection of the feeding rate (0.01 and 0.03 g/l/h) was investigated in a 5-L bioreactor. As a result, CHA production was increased by 57.9 mg/l with a 0.01 g/l/h ammonium acetate feeding rate. This work shows that the strategy of ammonium acetate supplementation had an effective role in improving CHA production by Aspergillus fumigatus CY018. It also shows that this strategy could serve as an important example of large-scale fermentation of a marine fungus in submerged culture.


Assuntos
Acetatos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/metabolismo , Suplementos Nutricionais , Fermentação , Alcaloides Indólicos/metabolismo , Aspergillus fumigatus/genética , Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos , Meios de Cultura/química , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/genética , Redes e Vias Metabólicas/efeitos dos fármacos , Nitrogênio/metabolismo , Ácido Chiquímico/metabolismo , Fatores de Tempo
9.
Artigo em Inglês | MEDLINE | ID: mdl-28582661

RESUMO

2,3-Dihydro-5-hydroxy-2-methylchromen-4-one (TL1-1) has already been reported to exhibit significant activities such as cytotoxicity, antifungal activity and growth inhibitory activity. In order to simply and efficiently separate TL1-1 from crude extracts of Daldinia eschscholzii on a large-preparative scale, XAD-16 resin was selected from ten types of resin based on its superior adsorption and desorption performance. Adsorption equilibrium data for this resin fitted well with pseudo-first order kinetics and the Freundlich model, which were elucidated from kinetic experiments and adsorption isotherms. Under optimized conditions, the purity of TL1-1 increased from 19.21% (w/w) in the crude extract, to 84.64% (w/w) in the final product, with a recovery yield of 75.06% (w/w) by a one-step treatment. Moreover, in a large-scale separation, the purity and recovery of TL1-1 was 80.33% and 72.02% (w/w), respectively. These results demonstrated that a simple adsorption-desorption strategy, using XAD-16 resin, was efficient, which also highlighted its potential for the future large-scale purification and preparation of TL1-1. In addition, studies showed that the purified TL1-1 exhibited moderate antibacterial activity against Ralstonia solanacearum.


Assuntos
Anti-Infecciosos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cromonas/isolamento & purificação , Extratos Vegetais/química , Xylariales/química , Adsorção , Anti-Infecciosos/análise , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Cromonas/análise , Cromonas/metabolismo , Cromonas/farmacologia , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Ralstonia/efeitos dos fármacos
10.
Bioresour Bioprocess ; 4(1): 1, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28133592

RESUMO

BACKGROUND: 2,3-Dihydro-5-hydroxy-2-methylchromen-4-one (TL1-1) is a phenolic compound with significant anti-fungal and anti-cancer activities produced by Daldinia eschscholzii (D. eschscholzii). However, studies have rarely been reported on the fermentation process of D. eschscholzii due to the urgent demand for its pharmaceutical researches and applications. RESULTS: In this work, the optimal fermentation medium for improved TL1-1 yield was first obtained in a shake flask. As the fermentation process was scaling up, the marked effects of dissolved oxygen (DO) on cell growth and TL1-1 biosynthesis were observed and confirmed. Controlling a suitable DO level by the adjustment of agitation speed and aeration rate remarkably enhanced TL1-1 production in a lab-scale bioreactor. Moreover, the fermentation of D. eschscholzii was successfully applied in 500-L bioreactor, and TL1-1 production has achieved 873.63 mg/L, approximately 15.4-fold than its initial production (53.27 mg/L). CONCLUSIONS: Dissolved oxygen control strategy for enhancing TL1-1 production was first proposed. Furthermore, control of the appropriate DO level has successfully performed for improving TL1-1 yield and scale-up of D. eschscholzii fermentation process.

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