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1.
Ying Yong Sheng Tai Xue Bao ; 34(11): 3085-3094, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37997420

RESUMEN

The reduction of agricultural emission plays an important role in realizing the dual-carbon goals. It is thus of great significance to examine the characteristics and drivers of regional agricultural carbon emission. We measured agricultural carbon emission in Jiangxi Province from the perspective of input-output and production processes, and explored the drivers and decoupling dynamics of agricultural carbon emission by using the LMDI decomposition method together with the Tapio decoupling model modified by time-varying parameter C-D production function. The results showed that agricultural carbon emission in Jiangxi increased by 26.4% from 2010 to 2021, and the carbon emission intensity decreased year by year with an average annual rate of 4.9%. Factors such as agricultural carbon intensity, labor input, and capital stock collectively reduced carbon emission by a total of 61.05 Mt, with a contribution of 27.0%, 44.5% and 28.5%, respectively. Level of agricultural economic development, agricultural structure, and technological progress had strong driving effects, which accounted for 75.7%, 5.6% and 18.8%, respectively. Agricultural carbon emission in Jiangxi was weakly decoupled from economic development, capital stock, and technological progress factors, but was negatively decoupled from labor input. Moreover, the decoupling state was more desirable in the later period than in the earlier period. Our results suggested that the application of the time-varying parameter C-D production function is innovative and applicable by incorporating technology, labor, and capital factors in the examination of carbon emission drivers and decoupling effects.


Asunto(s)
Carbono , Desarrollo Económico , Carbono/análisis , Agricultura , Dióxido de Carbono/análisis , China
2.
Artículo en Inglés | MEDLINE | ID: mdl-37096256

RESUMEN

Owing to the breakthroughs in the prevention and control of the COVID-19 pandemic, messenger RNA (mRNA)-based vaccines have emerged as promising alternatives to conventional vaccine approaches for infectious disease prevention and anticancer treatments. Advantages of mRNA vaccines include flexibility in designing and manipulating antigens of interest, scalability in rapid response to new variants, ability to induce both humoral and cell-mediated immune responses, and ease of industrialization. This review article presents the latest advances and innovations in mRNA-based vaccines and their clinical translations in the prevention and treatment of infectious diseases or cancers. We also highlight various nanoparticle delivery platforms that contribute to their success in clinical translation. Current challenges related to mRNA immunogenicity, stability, and in vivo delivery and the strategies for addressing them are also discussed. Finally, we provide our perspectives on future considerations and opportunities for applying mRNA vaccines to fight against major infectious diseases and cancers. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Biology-Inspired Nanomaterials > Lipid-Based Structures.


Asunto(s)
Enfermedades Transmisibles , Neoplasias , Vacunas , Humanos , Pandemias , ARN Mensajero , Vacunas de ARNm , Neoplasias/prevención & control
3.
Bioresour Technol ; 267: 227-234, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30025318

RESUMEN

This work investigated the effect of ethylenediamine pretreatment on reducing enzyme loading in high gravity fermentation. At optimal conditions of ethylenediamine pretreatment, 85.5% lignin was removed. Enzyme adsorption analysis using a fluorescent cellulose-binding protein showed 35.2% increase of productive adsorption of enzymes to ethylenediamine pretreated biomass, which was caused by high delignification and dramatically increased surface roughness and porosity. In SScF at 15% glucan loading, up to 82.2 g/L ethanol was achieved with a relatively low enzyme loading of 3.6 FPU/g dry matter. It suggested that the remarkably high digestibility of EDA pretreated corn stover could effectively reduce the enzyme loading in the high gravity fermentation of cellulosic ethanol.


Asunto(s)
Etilenodiaminas/química , Fermentación , Zea mays , Etanol , Hidrólisis , Hipergravedad , Lignina
4.
Biotechnol Biofuels ; 11: 118, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29713377

RESUMEN

BACKGROUND: Improving ethanol concentration and reducing enzyme dosage are main challenges in bioethanol refinery from lignocellulosic biomass. Ethylenediamine (EDA) pretreatment is a novel method to improve enzymatic digestibility of lignocellulose. In this study, simultaneous saccharification and co-fermentation (SSCF) process using EDA-pretreated corn stover was analyzed and optimized to verify the constraint factors on ethanol production. RESULTS: Highest ethanol concentration was achieved with the following optimized SSCF conditions at 6% glucan loading: 12-h pre-hydrolysis, 34 °C, pH 5.4, and inoculum size of 5 g dry cell/L. As glucan loading increased from 6 to 9%, ethanol concentration increased from 33.8 to 48.0 g/L, while ethanol yield reduced by 7%. Mass balance of SSCF showed that the reduction of ethanol yield with the increasing solid loading was mainly due to the decrease of glucan enzymatic conversion and xylose metabolism of the strain. Tween 20 and BSA increased ethanol concentration through enhancing enzymatic efficiency. The solid-recycled SSCF process reduced enzyme dosage by 40% (from 20 to 12 mg protein/g glucan) to achieve the similar ethanol concentration (~ 40 g/L) comparing to conventional SSCF. CONCLUSIONS: Here, we established an efficient SSCF procedure using EDA-pretreated biomass. Glucose enzymatic yield and yeast viability were regarded as the key factors affecting ethanol production at high solid loading. The extensive analysis of SSCF would be constructive to overcome the bottlenecks and improve ethanol production in cellulosic ethanol refinery.

5.
Science ; 355(6329)2017 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-28280151

RESUMEN

Perfect matching of an assembled physical sequence to a specified designed sequence is crucial to verify design principles in genome synthesis. We designed and de novo synthesized 536,024-base pair chromosome synV in the "Build-A-Genome China" course. We corrected an initial isolate of synV to perfectly match the designed sequence using integrative cotransformation and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated editing in 22 steps; synV strains exhibit high fitness under a variety of culture conditions, compared with that of wild-type V strains. A ring synV derivative was constructed, which is fully functional in Saccharomyces cerevisiae under all conditions tested and exhibits lower spore viability during meiosis. Ring synV chromosome can extends Sc2.0 design principles and provides a model with which to study genomic rearrangement, ring chromosome evolution, and human ring chromosome disorders.


Asunto(s)
Cromosomas Artificiales de Levadura/química , Genoma Fúngico , Saccharomyces cerevisiae/genética , Biología Sintética/métodos , Proteínas Bacterianas , Proteína 9 Asociada a CRISPR , Cromosomas Artificiales de Levadura/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Endonucleasas , Edición Génica , Reordenamiento Génico , Meiosis , Modelos Genéticos , Saccharomyces cerevisiae/citología , Transformación Genética
6.
Bioresour Technol ; 224: 342-348, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27919544

RESUMEN

In this study, wash liquors isolated from ethylenediamine and dry dilute acid pretreated corn stover were used to evaluate the effect of soluble materials in pretreated biomass on simultaneous saccharification and co-fermentation (SSCF) for ethanol production, respectively. Both of the wash liquors had different impacts on enzymatic hydrolysis and fermentation. Enzymatic conversions of glucan and xylan monotonically decreased as wash liquor concentration increased. Whereas, with low wash liquor concentrations, xylose consumption rate, cell viability and ethanol yield were maximally stimulated in fermentation without nutrient supplementary. Soluble lignins were found as the key composition which promoted sugars utilization and cell viability without nutrient supplementary. The dual effects of soluble materials on enzymatic hydrolysis and fermentation resulted in the reduction of ethanol yield as soluble materials increased in SSCF.


Asunto(s)
Etanol/metabolismo , Fermentación , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , Biomasa , Hidrólisis , Sacarosa/metabolismo , Xilosa/metabolismo , Zea mays
7.
Bioresour Technol ; 224: 405-410, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27865666

RESUMEN

In this study, the effect of ethylenediamine (EDA) on enzymatic hydrolysis with different cellulosic substrates and the approaches to reduce sugar loss in enzymatic hydrolysis were investigated. During enzymatic hydrolysis, xylose yield reduced 21.2%, 18.1% and 13.0% with 7.5mL/L EDA for AFEX pretreated corn stover (CS), washed EDA pretreated CS and CS cellulose. FTIR and GPC analysis demonstrated EDA reacted with sugar and produced high molecular weight (MW) compounds. EDA was prone to react with xylose other than glucose. H2O2 and Na2SO3 cannot prevent sugar loss in glucose/xylose-EDA mixture, although they inhibited the browning and high MW compounds formation. By decreasing temperature to 30°C, the loss of xylose yield reduced to only 3.8%, 3.6% and 4.2% with 7.5mL/L EDA in the enzymatic hydrolysis of AFEX pretreated CS, washed EDA pretreated CS and CS cellulose.


Asunto(s)
Carbohidratos/química , Celulasa/metabolismo , Etilenodiaminas/farmacología , Residuos/análisis , Zea mays/química , Glucosa/análisis , Peróxido de Hidrógeno/farmacología , Hidrólisis , Reacción de Maillard , Modelos Teóricos , Peso Molecular , Hipoclorito de Sodio/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Sulfitos/farmacología , Temperatura , Xilosa/análisis
8.
Bioresour Technol ; 218: 380-7, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27387414

RESUMEN

Co-culture of xylose-utilizing and inhibitor-tolerant Saccharomyces cerevisiae was developed for bioethanol production from undetoxified pretreated biomass in simultaneously saccharification and co-fermentation (SSCF) process. Glucose accumulation during late fermentation phase in SSCF using xylose-utilizing strain can be eliminated by the introduction of inhibitor-tolerant strain. Effect of different ratios of two strains was investigated and xylose-utilizing strain to inhibitor-tolerant strain ratio of 10:1 (w/w) showed the best xylose consumption and the highest ethanol yield. Inoculating of xylose-utilizing strain at the later stage of SSCF (24-48h) exhibited lower ethanol yield than inoculating at early stage (the beginning 0-12h), probably due to the reduced enzymatic efficiency caused by the unconsumed xylose and oligomeric sugars. Co-culture SSCF increased ethanol concentration by 21.2% and 41.0% comparing to SSCF using individual inhibitor-tolerant and xylose-utilizing strain (increased from 48.5 and 41.7g/L to 58.8g/L), respectively, which suggest this co-culture system was very promising.


Asunto(s)
Carbohidratos/química , Etanol/química , Fermentación , Glucosa/química , Saccharomyces cerevisiae/metabolismo , Xilosa/química , Biomasa , Biotecnología , Técnicas de Cocultivo , Hidrólisis , Lignina/química , Zea mays
9.
Bioresour Technol ; 209: 172-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26970919

RESUMEN

This study is aimed to examine the inhibition of soluble fraction (SF) and enzymatic residual fraction (ERF) in dry dilute acid (DDA), ethylenediamine (EDA) and steam explosion (SE) pretreated corn stover (CS) on the enzymatic digestibility of cellulose. SF of DDA, EDA and SE pretreated CS has high xylose, soluble lignin and xylo-oligomer content, respectively. SF of EDA pretreated CS leads to the highest inhibition, followed by SE and DDA pretreated CS. Inhibition of ERF of DDA and SE pretreated CS is higher than that of EDA pretreated CS. The inhibition degree (A0/A) of SF is 1.76 and 1.21 times to that of ERF for EDA and SE pretreated CS, respectively. The inhibition degree of ERF is 1.05 times to that of SF in DDA pretreated CS. The quantitative analysis shows that SF of EDA pretreated CS, SF and ERF of SE pretreated CS cause significant inhibition during enzymatic hydrolysis.


Asunto(s)
Celulosa/química , Zea mays/química , Ácidos/química , Biocombustibles , Celulosa/metabolismo , Etilenodiaminas/química , Hidrólisis , Lignina/análisis , Lignina/química , Vapor , Xilosa/análisis , Xilosa/química
10.
Biotechnol Biofuels ; 9: 70, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27006689

RESUMEN

BACKGROUND: Lignin-derived phenolic compounds are universal in the hydrolysate of pretreated lignocellulosic biomass. The phenolics reduce the efficiency of enzymatic hydrolysis and increase the cost of ethanol production. We investigated inhibition of phenolics on cellulase during enzymatic hydrolysis using vanillin as one of the typical lignin-derived phenolics and Avicel as cellulose substrate. RESULTS: As vanillin concentration increased from 0 to 10 mg/mL, cellulose conversion after 72-h enzymatic hydrolysis decreased from 53 to 26 %. Enzyme deactivation and precipitation were detected with the vanillin addition. The enzyme concentration and activity consecutively decreased during hydrolysis, but the inhibition degree, expressed as the ratio of the cellulose conversion without vanillin to the conversion with vanillin (A 0 /A), was almost independent on hydrolysis time. Inhibition can be mitigated by increasing cellulose loading or cellulase concentration. The inhibition degree showed linear relationship with the vanillin concentration and exponential relationship with the cellulose loading and the cellulase concentration. The addition of calcium chloride, BSA, and Tween 80 did not release the inhibition of vanillin significantly. pH and temperature for hydrolysis also showed no significant impact on inhibition degree. The presence of hydroxyl group, carbonyl group, and methoxy group in phenolics affected the inhibition degree. CONCLUSION: Besides phenolics concentration, other factors such as cellulose loading, enzyme concentration, and phenolic structure also affect the inhibition of cellulose conversion. Lignin-blocking agents have little effect on the inhibition effect of soluble phenolics, indicating that the inhibition mechanism of phenolics to enzyme is likely different from insoluble lignin. The inhibition of soluble phenolics can hardly be entirely removed by increasing enzyme concentration or adding blocking proteins due to the dispersity and multiple binding sites of phenolics than insoluble lignin.

11.
Biotechnol Biofuels ; 8: 174, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26516347

RESUMEN

BACKGROUND: Pretreatment of lignocellulosic biomass is essential to increase the cellulase accessibility for bioconversion of lignocelluloses by breaking down the biomass recalcitrance. In this work, a novel pretreatment method using ethylenediamine (EDA) was presented as a simple process to achieve high enzymatic digestibility of corn stover (CS) by heating the biomass-EDA mixture with high solid-to-liquid ratio at ambient pressure. The effect of EDA pretreatment on lignocellulose was further studied. RESULTS: High enzymatic digestibility of CS was achieved at broad pretreatment temperature range (40-180 °C) during EDA pretreatment. Herein, X-ray diffractogram analysis indicated that cellulose I changed to cellulose III and amorphous cellulose after EDA pretreatment, and cellulose III content increased along with the decrease of drying temperature and the increase of EDA loading. Lignin degradation was also affected by drying temperature and EDA loading. Images from scanning electron microscope and transmission electron microscope indicated that lignin coalesced and deposited on the biomass surface during EDA pretreatment, which led to the delamination of cell wall. HSQC NMR analysis showed that ester bonds of p-coumarate and ferulate units in lignin were partially ammonolyzed and ether bonds linking the phenolic monomers were broken during pretreatment. In addition, EDA-pretreated CS exhibited good fermentability for simultaneous saccharification and co-fermentation process. CONCLUSIONS: EDA pretreatment improves the enzymatic digestibility of lignocellulosic biomass significantly, and the improvement was caused by the transformation of cellulose allomorph, lignin degradation and relocalization in EDA pretreatment.

12.
Bioresour Technol ; 198: 39-46, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26363500

RESUMEN

Dry dilute acid pretreatment (DDAP) is a promising method for lignocellulose bioconversion, although inhibitors generated during the pretreatment impede the fermentation severely. We developed the simultaneous saccharification and co-fermentation (SScF) of DDAP pretreated biomass at high solid loading using xylose fermenting Saccharomyces cerevisiae, SyBE005. Effect of temperature on SScF showed that ethanol yield at 34°C was 10.2% higher than that at 38°C. Ethanol concentration reached 29.5 g/L at 15% (w/w) dry matter loading, while SScF almost ceased at the beginning at 25% (w/w) dry matter loading of DDAP pretreated corn stover. According to the effect of the diluted hydrolysate on the fermentation of strain SyBE005, a fed-batch mode was developed for the SScF of DDAP pretreated corn stover with 25% dry matter loading without detoxification, and 40.0 g/L ethanol was achieved. In addition, high yeast inoculation improved xylose utilization and the final ethanol concentration reached 47.2 g/L.


Asunto(s)
Ácidos/farmacología , Etanol/farmacología , Fermentación , Saccharomyces cerevisiae/efectos de los fármacos , Solventes/farmacología , Zea mays/efectos de los fármacos , Biomasa , Reactores Biológicos , Desecación , Lignina , Factores de Tiempo , Xilosa/farmacología
13.
Zhongguo Zhong Yao Za Zhi ; 40(8): 1610-3, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26281608

RESUMEN

In this paper, menstruation prescriptions were selected from "Fu Qingzhu's Obstetrics and Gynecology" and analyzed by using GRI algorithm, correlation analysis, hierarchical clustering method through SPSS, Clementine and traditional Chinese medicine (TCM) inheritance auxiliary systems, in order to screen out 15 menopathy prescriptions, which involve 45 traditional Chinese medicine herbs. In the study, blood-tonifying and qi-tonifying herbs were found to be frequent in the prescriptions. The most frequent single herb was white paeony root, accounting for 9.6% in the total number of prescriptions; The most frequent herb pairs were white paeony root-radix rehmanniae preparata and paeony root-angelica sinensis. Among Fu Shan's menopathy prescriptions, 61 herbal pairs showed a correlation coefficient exceeding 0.05, which evolved into 16 pairs of core combinations. The analysis showed that menopathy prescriptions in volume 1 of "Fu Qingzhu's Obstetrics and Gynecology" focused on tonic traditional Chinese medicines involving liver, spleen and kidney and were adjusted according to changes in qi, blood, cold, hot and wet, which could provide a specific reference for further studies on Fu Shan's academic thoughts and traditional Chinese medicine clinical treatment of menopathy.


Asunto(s)
Libros/historia , Prescripciones de Medicamentos/historia , Quimioterapia/historia , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/uso terapéutico , Menstruación/efectos de los fármacos , China , Femenino , Ginecología , Historia Antigua , Humanos , Medicina en la Literatura
14.
Biotechnol Biofuels ; 7(1): 167, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25516770

RESUMEN

BACKGROUND: Simultaneous saccharification and fermentation (SSF) is a promising process for bioconversion of lignocellulosic biomass. High glucan loading for hydrolysis and fermentation is an efficient approach to reduce the capital costs for bio-based products production. The SSF of steam-exploded corn stover (SECS) for ethanol production at high glucan loading and high temperature was investigated in this study. RESULTS: Glucan conversion of corn stover biomass pretreated by steam explosion was maintained at approximately 71 to 79% at an enzyme loading of 30 filter paper units (FPU)/g glucan, and 74 to 82% at an enzyme loading of 60 FPU/g glucan, with glucan loading varying from 3 to 12%. Glucan conversion decreased obviously with glucan loading beyond 15%. The results indicated that the mixture was most efficient in enzymatic hydrolysis of SECS at 3 to 12% glucan loading. The optimal SSF conditions of SECS using a novel Saccharomyces cerevisiae were inoculation optical density (OD)600 = 4.0, initial pH 4.8, 50% nutrients added, 36 hours pre-hydrolysis time, 39°C, and 12% glucan loading (20% solid loading). With the addition of 2% Tween 20, glucan conversion, ethanol yield, final ethanol concentration reached 78.6%, 77.2%, and 59.8 g/L, respectively, under the optimal conditions. The results suggested that the solid and degradation products' inhibitory effect on the hydrolysis and fermentation of SECS were also not obvious at high glucan loading. Additionally, glucan conversion and final ethanol concentration in SSF of SECS increased by 13.6% and 18.7%, respectively, compared with separate hydrolysis and fermentation (SHF). CONCLUSIONS: Our research suggested that high glucan loading (6 to 12% glucan loading) and high temperature (39°C) significantly improved the SSF performance of SECS using a thermal- and ethanol-tolerant strain of S. cerevisiae due to the removal of degradation products, sugar feedback, and solid's inhibitory effects. Furthermore, the surfactant addition obviously increased ethanol yield in SSF process of SECS.

15.
Bioresour Technol ; 169: 9-18, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25016219

RESUMEN

Co-fermentation of glucose and xylose from lignocelluloses is an efficient approach to increasing ethanol production. Simultaneous saccharification and co-fermentation (SSCF) of corn stover pretreated with aqueous ammonia was performed using engineered yeast with xylose utilization pathway. Thus far, the effect of the several key factors on SSCF was investigated, including temperature, inoculation size, pre-hydrolysis and pH. Ethanol concentration was achieved to 36.5 g/L during SSCF process with 6% glucan loading. The addition of Tween 20 reduced enzyme loading, i.e., from 15 to 7.5 FPU/gglucan with the same final ethanol concentration. The ethanol concentration was achieved to 70.1g/L at 12% glucan loading. Yeast feeding, combined with substrate and enzyme feeding, was proved to be an efficient approach for SSCF with high solid loading.


Asunto(s)
Amoníaco/farmacología , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Fermentación/efectos de los fármacos , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/metabolismo , Residuos , Zea mays/química , Técnicas de Cultivo Celular por Lotes , Concentración de Iones de Hidrógeno , Hidrólisis/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Temperatura , Factores de Tiempo , Xilosa/metabolismo
16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 20(5): 417-20, 2003 Oct.
Artículo en Chino | MEDLINE | ID: mdl-14556196

RESUMEN

OBJECTIVE: Platelet membrane glycoprotein (GP) Ia/IIa complex is the major collagen receptor on platelets. Platelet activation by GP Ia/ IIa dependent adhesion leads to cellular events that catalyze prothrombin conversion and fibrin clot formation. Correlation between the polymorphism of platelet membrane GP Ia gene and myocardial infarction (MI) was explored. METHODS: A total of 137 patient s with myocardial infarction and 175 controls with no history of coronary heart disease, thrombogenic and hemorrhagenic diseases were studied by case-control. Platelet GP I a gene 807 C/T polymorphisms were checked by polymerase chain reaction-sequence specific primers. RESULTS: There were significant differences in the distribution of T and C alleles between MI and control groups (T:42.70% vs 32.00%, C:57.30% vs 68.00%, P<0.001). No matter among all subjects or among subjects aged

Asunto(s)
Integrina alfa2/genética , Infarto del Miocardio/genética , Polimorfismo Genético , Anciano , Alelos , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/patología
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