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1.
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 35(3): 209-211;215, 2021 Mar.
Artículo en Chino | MEDLINE | ID: mdl-33794603

RESUMEN

Objective: To study whether the warm/cold air injection sequence affects the test results in the caloric test, and provide a basis for the specification and quality control of the caloric test. Methods:Video nystagmography and warm and cold air stimulation apparatus were applied for caloric test. Thirty healthy volunteers (60 ears) were divided into two groups of 15 (30 ears) each. The first group was given cold air stimulation followed by warm air stimulation, and the second group was given heat followed by cold. The differences in nystagmus maximal slow phase velocity (SPV), semicircular canal paresis (CP) and dominant preponderance (DP) were compared between the two groups of subjects under different perfusion sequences of caloric test. Results:The intensity of nystagmus evoked by subjects in group 1 (cold first and then warm) and group 2 (warm first and then cold) were similar. Paired t-test showed that intra-group analysis of the SPV values of the two groups, comparison of the intensity of nystagmus evoked by different temperatures of the same ear or different sides of ear with the same temperature, the difference was not statistically significant (all P>0.05). Independent samples t-test showed that between-group analysis of SPV values of two groups, the intensity of nystagmus induced by the same and different temperature stimuli in the ipsilateral ear, the difference was not statistically significant (all P>0.05). Independent samples t-test showed that the CP values of the two groups were analyzed between groups, and the difference was not statistically significant (all P>0.05). Independent samples t-test showed that DP values of both groups were in the normal range and the difference was not statistically significant (all P>0.05). Conclusion:Different perfusion sequences of warm and cold air do not affect the results of caloric tests, and the order of warm and cold air stimulation is not the normative and quality control research direction of caloric test.


Asunto(s)
Pruebas Calóricas , Nistagmo Patológico , Frío , Calor , Humanos , Perfusión
2.
mSphere ; 6(2)2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789940

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carrying the D614G mutation on the spike protein is the predominant circulating variant and is associated with enhanced infectivity. However, whether this dominant variant can potentially spread through the cold chain and whether the spike protein affects virus stability after cold storage remain unclear. To compare the infectivity of two SARS-CoV-2 variants, namely, SARS-CoV-2 variants with spike protein with the D614 mutation (S-D614) and G614 mutation (S-G614), after different periods of refrigeration (4°C) and freezing (-20°C). We also determined the integrity of the viral RNA and the ability of the spike protein to bind angiotensin-converting enzyme 2 (ACE2) after storage at these conditions. The results showed that SARS-CoV-2 was more stable and infectious after storage at -20°C than at 4°C. Particularly, the S-G614 variant was found to be more stable than the S-D614 variant. The spike protein of the S-G614 variant had better binding ability with the ACE2 receptor than that of the S-D614 variant after storage at -20°C for up to 30 days. Our findings revealed that SARS-CoV-2 remains stable and infectious after refrigeration or freezing, and their stability and infectivity up to 30 days depends on the spike variant. Stability and infectivity are related to each other, and the higher stability of S-G614 compared to that of S-D614 may contribute to rapid viral spread of the S-G614 variant.IMPORTANCE It has been observed that variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more stable and infectious after storage at -20°C than at 4°C. A SARS-CoV-2 S-D614G variant is currently the most dominant variant in circulation and is associated with enhanced infectivity. We compared the stability of two SARS-CoV-2 variants: the early S-D614 variant carrying the D614 spike protein and the new S-G614 variant carrying the G614 spike protein, stored at both 4°C and -20°C for different periods. We observed that SARS-CoV-2 remains stable and infectious after refrigeration or freezing, which further depends on the spike variant, that is, the ability of the spike protein to bind with the ACE2 receptor with higher efficiency. The high stability of the S-G614 variant also explains its rapid spread and infectivity. Therefore, precautions should be taken during and after handling food preserved under cold conditions.


Asunto(s)
/genética , Glicoproteína de la Espiga del Coronavirus/genética , Frío , Aptitud Genética/genética , Humanos , Mutación , Estabilidad Proteica
3.
Food Chem ; 351: 129336, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33662909

RESUMEN

To investigate the effect of relative humidity (RH) on chilling injury (CI), zucchini fruit were stored in cold rooms (4 ± 0.4 ℃) with different RHs (near-saturated RH [NSH] with 96-100% and normal RH with 72-76% served as control). Storage in NSH delayed weight loss and CI, maintained firmness and skin color. Higher antioxidant enzyme activities and greater scavenging capacities of free radicals were found in NSH-fruit than in the control fruit. The decrease of the unsaturated fatty acids was delayed in NSH-fruit due to lower activities of related membrane lipid degrading enzymes as compared to the control fruit. NSH-fruit also maintained higher activities of energy metabolism-associated enzymes than control fruit, leading to high levels of adenosine triphosphate (ATP). Taken together, we attributed the alleviation of CI by NSH storage to its enhancement of antioxidant capacities and its effect on maintaining higher energy status in zucchini fruit.


Asunto(s)
Antioxidantes/metabolismo , Frío , Cucurbita/metabolismo , Metabolismo Energético , Frutas/metabolismo , Humedad , Adenosina Trifosfato/metabolismo , Almacenamiento de Alimentos
4.
Nat Commun ; 12(1): 1516, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33750795

RESUMEN

Mild cold acclimation for 10 days has been previously shown to markedly improve insulin sensitivity in patients with type 2 diabetes. Here we show in a single-arm intervention study (Trialregister.nl ID: NL4469/NTR5711) in nine patients with type 2 diabetes that ten days of mild cold acclimation (16-17 °C) in which observable, overt shivering was prevented, does not result in improved insulin sensitivity, postprandial glucose and lipid metabolism or intrahepatic lipid content and only results in mild effects on overnight fasted fat oxidation, postprandial energy expenditure and aortic augmentation index. The lack of marked metabolic effects in this study is associated with a lack of self-reported shivering and a lack of upregulation of gene expression of muscle activation or muscle contraction pathways in skeletal muscle and suggests that some form of muscle contraction is needed for beneficial effects of mild cold acclimation.


Asunto(s)
Aclimatación/fisiología , Regulación de la Temperatura Corporal/fisiología , Frío , Diabetes Mellitus Tipo 2/metabolismo , Anciano , Ayuno , Femenino , Glucosa/metabolismo , Humanos , Resistencia a la Insulina , Cinética , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Músculo Esquelético , Oxidación-Reducción
5.
Int J Food Microbiol ; 344: 109108, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33667851

RESUMEN

The study determined the growth kinetic parameters of a cocktail of Listeria monocytogenes 1/2c and 4b strains in coconut water (pH 4.76, 5.0°Brix, 0.09% malic acid, aw 0.998) subjected to low (~2.0 log CFU/mL) and high (~4.0 log CFU/mL) contamination levels, and exposed to different storage temperatures (4 °C, 17 °C, 30 °C, and 35 °C). The pathogen proliferated in all tested conditions except in that with low contamination stored at 4 °C. Despite not growing at 4 °C, the pathogen was detectable throughout the storage period, which lasted for almost 400 h. In conditions where the pathogens proliferated, growth lag (tlag) ranged from 0.0 to 68.3 h. The growth rates (KG) ranged from 0.05 to 0.48 log CFU/h, while the final populations ranged from 6.3 to 8.7 log CFU/mL. Both storage temperature and contamination level significantly (P < 0.05) affected the growth parameters. Sanitary risk times (SRT) were determined with the microbiological shelf life (SL) of coconut water. In some of the conditions tested, SRT took place before SL (SRT < SL), emphasizing the importance of having good hygienic and manufacturing practices in place for such a vulnerable commodity.


Asunto(s)
Cocos/microbiología , Conservación de Alimentos , Almacenamiento de Alimentos , Listeria monocytogenes/crecimiento & desarrollo , Frío , Recuento de Colonia Microbiana , Manipulación de Alimentos , Microbiología de Alimentos , Calor
6.
Food Chem ; 352: 129402, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690074

RESUMEN

A non-thermal processing method was developed to promote preservation of brown rice using dielectric barrier discharge cold plasma (DBD-CP). Physicochemical properties including free fatty acid (FFA) content, surface color change, volatile organic components (VOCs) and flavor fingerprints were evaluated in brown rice submitted to DBD-CP. FFA levels were 25.2% lower in treated samples compared to the control, and a more stable surface color was obtained at the end of the storage period. A total of 35 major VOCs could be detected in treated samples, and reduced levels of hexanal can be used as an indicator of DBD-CP treatment in brown rice during storage. Moreover, the flavor fingerprints in DBD-CP treated groups can be successfully distinguished through headspace gas chromatography ion mobility spectrometry. Collectively, application of DBD-CP treatment could be utilized as a feasible approach to promote stabilization of brown rice and preserve flavor during storage.


Asunto(s)
Frío , Oryza/química , Gases em Plasma/química , Gusto , Impedancia Eléctrica , Compuestos Orgánicos Volátiles/análisis
7.
Molecules ; 26(4)2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33669237

RESUMEN

Yeast plays a key role in the production of fermented foods and beverages, such as bread, wine, and other alcoholic beverages. They are able to produce and release from the fermentation environment large numbers of volatile organic compounds (VOCs). This is the reason for the great interest in the possibility of adapting these microorganisms to fermentation at reduced temperatures. By doing this, it would be possible to obtain better sensory profiles of the final products. It can reduce the addition of artificial flavors and enhancements to food products and influence other important factors of fermented food production. Here, we reviewed the genetic and physiological mechanisms by which yeasts adapt to low temperatures. Next, we discussed the importance of VOCs for the food industry, their biosynthesis, and the most common volatiles in fermented foods and described the beneficial impact of decreased temperature as a factor that contributes to improving the composition of the sensory profiles of fermented foods.


Asunto(s)
Adaptación Fisiológica , Frío , Ambiente , Fermentación , Saccharomyces cerevisiae/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Adaptación Fisiológica/genética , Fermentación/genética , Saccharomyces cerevisiae/genética
8.
Food Chem ; 351: 129227, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33647695

RESUMEN

Cold chain transportation is an important link in postharvest logistics of agricultural products. In current study, we developed a novel water-based phase change coolant (PCC), which showed longer effectiveness in maintaining low temperature condition compared with ice, and applied in preserving the postharvest mushrooms. The results showed that the novel PCC effectively inhibited water loss, as well as maintained quality attributes including firmness, color, phenolics, flavonoids, and thus prolonged the shelf-life of mushrooms. Low temperature condition created by the novel PCC treatment maintained high level of energy charge by activating the activities of SDH, CCO, H+-ATPase and Ca2+-ATPase, resulting in the delay of postharvest senescence. In addition, sufficient energy supply decreased the consumption of glutamate as carbon skeleton by inhibiting GDH activity, improved glutamate accumulation, and therefore maintained sensory properties as a result. Thus, the novel PCC might be an excellent substitute for ice in cold chain transportation of mushrooms.


Asunto(s)
Frío , Metabolismo Energético/efectos de los fármacos , Calidad de los Alimentos , Ácido Glutámico/metabolismo , Transición de Fase , Hongos Shiitake/química , Hongos Shiitake/metabolismo , Color , Hongos Shiitake/efectos de los fármacos , Agua/química , Agua/farmacología
9.
Plant Mol Biol ; 105(6): 585-599, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33651261

RESUMEN

KEY MESSAGE: Total of 14 SNPs associated with overwintering-related traits and 75 selective regions were detected. Important candidate genes were identified and a possible network of cold-stress responses in woody plants was proposed. Local adaptation to low temperature is essential for woody plants to against changeable climate and safely survive the winter. To uncover the specific molecular mechanism of low temperature adaptation in woody plants, we sequenced 134 core individuals selected from 494 paper mulberry (Broussonetia papyrifera), which naturally distributed in different climate zones and latitudes. The population structure analysis, PCA analysis and neighbor-joining tree analysis indicated that the individuals were classified into three clusters, which showed forceful geographic distribution patterns because of the adaptation to local climate. Using two overwintering phenotypic data collected at high latitudes of 40°N and one bioclimatic variable, genome-phenotype and genome-environment associations, and genome-wide scans were performed. We detected 75 selective regions which possibly undergone temperature selection and identified 14 trait-associated SNPs that corresponded to 16 candidate genes (including LRR-RLK, PP2A, BCS1, etc.). Meanwhile, low temperature adaptation was also supported by other three trait-associated SNPs which exhibiting significant differences in overwintering traits between alleles within three geographic groups. To sum up, a possible network of cold signal perception and responses in woody plants were proposed, including important genes that have been confirmed in previous studies while others could be key potential candidates of woody plants. Overall, our results highlighted the specific and complex molecular mechanism of low temperature adaptation and overwintering of woody plants.


Asunto(s)
Adaptación Fisiológica/genética , Frío , Fenómenos Fisiológicos de las Plantas , Plantas/genética , Alelos , Secuencia de Bases , Clima , Estudio de Asociación del Genoma Completo , Morus/genética , Morus/fisiología , Fenotipo , Polimorfismo de Nucleótido Simple , Temperatura
10.
Food Chem ; 352: 129458, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33714166

RESUMEN

We investigated the effect of exogenous glutathione (GSH) on chilling injury (CI) in postharvest bell pepper fruits stored at low temperature and explored the mechanism of this treatment from the perspective of the ascorbate-glutathione (AsA-GSH) cycle. Compared with the control, fruits treated with exogenous GSH before refrigeration displayed only slight CI symptoms and mitigated CI-induced cell damage after 10 d. Moreover, the treated peppers had lower lipid peroxidation product, H2O2, and O2- content than those did the control. Glutathione treatment enhanced the ascorbate-glutathione cycle by upregulating CaAPX1, CaGR2, CaMDHAR1, and CaDHAR1 and the antioxidant enzymes APX, GR, and MDHAR associated with the ascorbate-glutathione cycle. Glutathione treatment also increased ascorbate and glutathione concentrations. Taken together, our results showed that exogenous GSH treatment could alleviate CI in pepper fruits during cold storage by triggering the AsA-GSH cycle and improving antioxidant capacity.


Asunto(s)
Ácido Ascórbico/metabolismo , Capsicum/efectos de los fármacos , Capsicum/metabolismo , Frío , Glutatión/farmacología , Frutas/efectos de los fármacos , Frutas/metabolismo , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Plantones/efectos de los fármacos , Plantones/metabolismo
11.
Int J Mol Sci ; 22(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671465

RESUMEN

To change their behaviors, cells require actin proteins to assemble together into long polymers/filaments-and so a critical goal is to understand the factors that control this actin filament (F-actin) assembly and stability. We have identified a family of unusual actin regulators, the MICALs, which are flavoprotein monooxygenase/hydroxylase enzymes that associate with flavin adenine dinucleotide (FAD) and use the co-enzyme nicotinamide adenine dinucleotide phosphate (NADPH) in Redox reactions. F-actin is a specific substrate for these MICAL Redox enzymes, which oxidize specific amino acids within actin to destabilize actin filaments. Furthermore, this MICAL-catalyzed reaction is reversed by another family of Redox enzymes (SelR/MsrB enzymes)-thereby revealing a reversible Redox signaling process and biochemical mechanism regulating actin dynamics. Interestingly, in addition to the MICALs' Redox enzymatic portion through which MICALs covalently modify and affect actin, MICALs have multiple other domains. Less is known about the roles of these other MICAL domains. Here we provide approaches for obtaining high levels of recombinant protein for the Redox only portion of Mical and demonstrate its catalytic and F-actin disassembly activity. These results provide a ground state for future work aimed at defining the role of the other domains of Mical - including characterizing their effects on Mical's Redox enzymatic and F-actin disassembly activity.


Asunto(s)
Actinas/metabolismo , Drosophila melanogaster/enzimología , Pruebas de Enzimas , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/metabolismo , Animales , Biocatálisis , Chaperoninas/metabolismo , Frío , Oxidación-Reducción , Dominios Proteicos , Proteínas Recombinantes/aislamiento & purificación , Solubilidad
12.
Infez Med ; 29(1): 160-162, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33664187
13.
J Environ Sci (China) ; 103: 172-184, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33743899

RESUMEN

To improve the removal capacity of NO + O2 effectively, the alkaline earth metal-doped order mesoporous carbon (A-C-FDU-15(0.001) (A = Mg, Ca, Sr and Ba)) and Mg-C-FDU-15(x) (x = 0.001-0.003) samples were prepared, and their physicochemical and NO + O2 adsorption properties were determined by means of various techniques. The results show that the sequence in (NO + O2) adsorption performance was as follows: Mg-C-FDU-15(0.001) (93.2 mg/g) > Ca-C-FDU-15(0.001) (82.2 mg/g) > Sr-C-FDU-15(0.001) (76.1 mg/g) > Ba-C-FDU-15(0.001) (72.9 mg/g) > C-FDU-15 (67.1 mg/g). Among all of the A-C-FDU-15(0.001) samples, Mg-C-FDU-15(0.001) possessed the highest (NO + O2) adsorption capacity (106.2 mg/g). The species of alkaline earth metals and basic sites were important factors determining the adsorption of NO + O2 on the A-C-FDU-15(x) samples, and (NO + O2) adsorption on the samples was mainly chemical adsorption. Combined with the results of (NO + O2)-temperature-programmed desorption ((NO + O2)-TPD) and in situ diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) characterization, we deduced that there were two main pathways of (NO + O2) adsorption: one was first the conversion of NO and O2 to NO2 and then part of NO2 was converted to NO2- and NO3-; and the other was the direct oxidation of NO to NO2- and NO3-.


Asunto(s)
Frío , Metales Alcalinotérreos , Adsorción , Oxidación-Reducción , Temperatura
14.
Asian Cardiovasc Thorac Ann ; 29(2): 77-83, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33530706

RESUMEN

BACKGROUND: Despite the increasing popularity of single-dose cardioplegia techniques in coronary artery bypass grafting, the time window for successful reperfusion remains unclear. This study aimed to compare different cardioplegic techniques based on early and 30-day clinical outcomes via thorough monitoring. METHODS: This prospective cohort study included high-risk patients undergoing coronary artery bypass grafting and receiving 3 different types of cardioplegia between January 2017 and June 2019. Group 1 (n = 101) had a single dose of del Nido cardioplegia, group 2 (n = 92) had a single dose of histidine-tryptophane-ketoglutarate, and group 3 (n = 119) had cold blood cardioplegia. Patients were examined perioperatively by memory loop recording and auto-triggered memory loop recording for 30 days, with documentation of predefined events. RESULTS: Interleukin-6 and cardiac troponin levels in group 1 were significantly higher than those in groups 2 and 3. The incidence of predefined events as markers of inadequate myocardial protection was significantly higher group 1, with more frequent atrial fibrillation attacks and more hospital readmissions. The readmission rate was 17.6% in group 1, 9% in group 2, and 8% in group 3. CONCLUSIONS: Our data demonstrate the long-term efficacy of cardioplegic techniques, which may become more crucial in high-risk patients who genuinely have a chance to benefit from adjunct myocardial protection. Patients given del Nido cardioplegia had a significantly more prominent inflammatory response and higher troponin levels after cardiopulmonary bypass. This group had issues in the longer term with significantly more cardiac events and a higher rehospitalization rate.


Asunto(s)
Frío , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Electrólitos/uso terapéutico , Paro Cardíaco Inducido , Lidocaína/uso terapéutico , Sulfato de Magnesio/uso terapéutico , Manitol/uso terapéutico , Cloruro de Potasio/uso terapéutico , Bicarbonato de Sodio/uso terapéutico , Soluciones/uso terapéutico , Anciano , Biomarcadores/sangre , Frío/efectos adversos , Puente de Arteria Coronaria/efectos adversos , Electrólitos/efectos adversos , Femenino , Glucosa/efectos adversos , Glucosa/uso terapéutico , Paro Cardíaco Inducido/efectos adversos , Humanos , Interleucina-6/sangre , Lidocaína/efectos adversos , Sulfato de Magnesio/efectos adversos , Masculino , Manitol/efectos adversos , Persona de Mediana Edad , Readmisión del Paciente , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/terapia , Cloruro de Potasio/efectos adversos , Procaína/efectos adversos , Procaína/uso terapéutico , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Bicarbonato de Sodio/efectos adversos , Soluciones/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Troponina/sangre
15.
Food Chem ; 349: 129159, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33545604

RESUMEN

The effect of dry heat (DH, 130 °C, 1, 3 and 9 h), cold plasma (CP, 40 V, 1, 5 and 10 min) and their combination (D-P) treatment on the structure, physicochemical and digestive properties of red adzuki bean starch were studied. The results showed that DH or CP had slight change in morphology while diffraction pattern of starch was remained. With the extension of treated time of DH and CP, the amylose content, crystallinity, molecular weight, short-range order, the long chain of amylopectin, enthalpy value, swelling power, digestibility were reduced, while gelatinization temperatures, the short chain of amylopectin and solubility were increased. The D-P had deeper modification than the single treatment. The combination of dry heat and cold plasma is a simple and green method to improve the starch structure and enhance starch properties and this modified starch could be implemented to tailor starch to the desired food applications.


Asunto(s)
Frío , Digestión , Calor , Gases em Plasma/química , Almidón/química , Almidón/metabolismo , Vigna/química , Manipulación de Alimentos , Gelatina/química , Peso Molecular , Solubilidad , Termodinámica
16.
Artículo en Inglés | MEDLINE | ID: mdl-33572714

RESUMEN

A steady and proper thermal environment in deep underground is imperative to ensure worker health and production safety. Understanding the thermal performance in the roadway is the premise of temperature prediction; ventilation design; and improvement in cooling efficiency. A full coupled model incorporated with a moving mesh method was adopted; reflecting the dynamic condition of roadway construction. This study revealed the characteristics of the thermal performance and its evolution law in an excavating roadway. Several scenarios were performed to examine the designs of the auxiliary ventilation system on thermal performance in the roadway. The results show that there is a limitation in the cooling effect by continuously increasing the ventilation volume. Reducing the diameter of the air duct or distances between the duct outlet and the working face will aggravate the heat hazard in the roadway. The heat release from the roadway wall increases with the increase of the advance rate of the working face or roadway section size. Furthermore; an orthogonal experiment was conducted to investigate the effect of major factors on the average air temperature and local heat accumulation in the roadway.


Asunto(s)
Aire Acondicionado , Ventilación , Frío , Calor , Temperatura
17.
Food Chem ; 350: 129212, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609939

RESUMEN

A novel alkaline cold-active phospholipase C (PLC) gene (AoPC) from Aspergillus oryzae was cloned. AoPC exhibited the highest sequence similarity of 32.5% with that of a PLC from Arabidopsis thaliana. The gene was co-expressed in Pichia pastoris with molecular chaperone PDI (protein disulfide isomerases), and the highest PLC activity of 82, 782 U mL-1 was achieved in a 5-L fermentor. The recombinant enzyme (AoPC) was most active at pH 8.0 and 25 °C, respectively, and it was stable over a broad pH range of 4.5-9.0 and up to 40 °C. It is the first fungal alkaline PLC. The application of AoPC (with 25% citric acid, w/w) in oil degumming process significantly reduced the phosphorus of crude soybean oil by 93.3% to a commercially acceptable level (<10 mg kg-1). Therefore, the relatively high yield and excellent properties of AoPC may possess it great potential in crude oil refining industry.


Asunto(s)
Aspergillus oryzae/enzimología , Frío , Ingeniería Genética/métodos , Chaperonas Moleculares/genética , Petróleo/análisis , Fosfolipasas de Tipo C/biosíntesis , Fosfolipasas de Tipo C/metabolismo , Clonación Molecular , Expresión Génica , Concentración de Iones de Hidrógeno , Pichia/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fosfolipasas de Tipo C/genética
18.
Food Chem ; 350: 129186, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33618091

RESUMEN

The aroma profile of raw pu'er tea (RPT) depends on its storage duration (2-10 years) and storage conditions (wet-hot or dry-cold environment). We analyzed the major odorants of RPT samples by performing metabolomic analysis and by using the molecular sensory science approach. Under dry-cold storage conditions, tea leaves had more carotenoid derivatives, glycoside-derived volatiles, and phenolic volatiles, resulting in "fresh," "floral," and "sweet" aroma. Under wet-hot storage conditions, tea leaves had more methoxybenzenes, which contributed considerably to their "stale" and "woody" aroma. We identified 11 and 4 compounds as the odor markers of RPTs when stored in dry-cold and wet-hot environments, respectively. Our findings provide a scientific basis for optimal storage that yields the desired aroma profile.


Asunto(s)
Frío , Calor , Metabolómica , Gusto , Té/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
20.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33562320

RESUMEN

Chloroplast ribonucleoproteins (cpRNPs) are nuclear-encoded and highly abundant proteins that are proposed to function in chloroplast RNA metabolism. However, the molecular mechanisms underlying the regulation of chloroplast RNAs involved in stress tolerance are poorly understood. Here, we demonstrate that CHLOROPLAST RNA-BINDING PROTEIN 1 (OsCRP1), a rice (Oryza sativa) cpRNP gene, is essential for stabilization of RNAs from the NAD(P)H dehydrogenase (NDH) complex, which in turn enhances drought and cold stress tolerance. An RNA-immunoprecipitation assay revealed that OsCRP1 is associated with a set of chloroplast RNAs. Transcript profiling indicated that the mRNA levels of genes from the NDH complex significantly increased in the OsCRP1 overexpressing compared to non-transgenic plants, whereas the pattern in OsCRP1 RNAi plants were opposite. Importantly, the OsCRP1 overexpressing plants showed a higher cyclic electron transport (CET) activity, which is essential for elevated levels of ATP for photosynthesis. Additionally, overexpression of OsCRP1 resulted in significantly enhanced drought and cold stress tolerance with higher ATP levels compared to wild type. Thus, our findings suggest that overexpression of OsCRP1 stabilizes a set of mRNAs from genes of the NDH complex involved in increasing CET activity and production of ATP, which consequently confers enhanced drought and cold tolerance.


Asunto(s)
Proteínas de Cloroplastos/metabolismo , Cloroplastos/genética , Frío , Sequías , Oryza/crecimiento & desarrollo , Estabilidad del ARN , Ribonucleoproteínas/metabolismo , Proteínas de Cloroplastos/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Fotosíntesis , Ribonucleoproteínas/genética , Estrés Fisiológico
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