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Colletotrichum gloeosporioides is the causal pathogen for the devastating walnuts anthracnose. A novel quinone inside inhibitor (QiI) fungicide florylpicoxamid has strong inhibitory efficacy against C. gloeosporioides. This study looked into the resistance risk and mechanism of C. gloeosporioides to florylpicoxamid. The basal level sensitivity of C. gloeosporioides isolates (n = 102) to florylpicoxamid was established with an average 50% mycelial growth inhibition concentration (EC50) value of 0.069 ± 0.035 µg/mL. Six stable florylpicoxamid-resistant mutants with resistance factors of >1000 were produced. The fitness of every mutant was much lower than that of their parental isolates. In general, the resistance risk of C. gloeosporioides to florylpicoxamid would be moderate. Molecular docking results revealed that the amino acid substitutions A37V, and S207L in CgCytb lead to a reduction in the binding affinity between florylpicoxamid and CgCytb, indicating that these two mutations (S207L and A37V in CgCytb) indeed confer florylpicoxamid resistance in C. gloeosporioides. These findings offer a fresh viewpoint on the mechanism underlying QiI fungicide resistance and could support the prudent application of florylpicoxamid in the future to combat walnut anthracnose.
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Colletotrichum , Farmacorresistencia Fúngica , Fungicidas Industriales , Juglans , Simulación del Acoplamiento Molecular , Colletotrichum/efectos de los fármacos , Colletotrichum/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungicidas Industriales/farmacología , Juglans/microbiología , Mutación , Enfermedades de las Plantas/microbiologíaRESUMEN
In order to explore the effects of different pretreatment methods on the ultrasonic far-infrared synergistic drying characteristics and quality of wolfberry, the bioactive components (polysaccharide, total phenol, total flavonoids, and antioxidants), the quality characteristics (rehydration ratio, color, vitamin C content, and betaine content), and the microstructure of the dried products were used as evaluation indices to test wolfberry treated by five different pretreatments (hot blanching; candied pretreatment; NaOH solution treatment; NaCl solution treatment; and Na2CO3 solution treatment). The results showed that hot blanching pretreatment improved the drying rate and shortened the drying time, and that the vitamin C content of dried products pretreated by hot blanching (92.56 mg/100 g) was higher than that of dried products pretreated by other methods. All five pretreatment methods increased the contents of the total phenols, vitamin C, and betaine of wolfberry. Wolfberry treated by candied pretreatment had lower color differences and higher contents of polysaccharide (0.83 g/g), total phenol (9.26 mg/g), and total flavonoids (2.61 mg/g) than wolfberry treated by the other pretreatment methods. Wolfberry pretreated by NaCl solution had the strongest antioxidant capacity (65.01%). Wolfberry pretreated by Na2CO3 solution had the highest betaine content (3.24%). The observation of the microstructure of the dried products revealed that hot blanching caused the most damage to wolfberry, while the candied pretreatment was less destructive to the tissue cells of wolfberry. On the whole, the dried wolfberry products obtained by the candied pretreatment were of a better quality than products obtained by the other pretreatment methods.
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Lycium , Lycium/química , Ultrasonido , Fenol , Betaína , Cloruro de Sodio , Antioxidantes/química , Ácido Ascórbico/química , Desecación/métodos , Fenoles , Flavonoides , PolisacáridosRESUMEN
Ultrasonic (US) maltreatment was performed before the vacuum far-infrared drying (VFID) of Codonopsis pilosula (CP) slices to investigate the effects of different US parameters on the drying characteristics and nutrients of CP slices. The grey correlation method with relative correlation degree (ri) as the evaluation measure was used to construct a model for the evaluation of the pretreatment quality of CP and to determine the optimal pretreatment conditions. The results showed that with the increase in US frequency and power, the drying rate increased. Under the conditions of US power of 180 W, frequency of 60 kHz and a pre-treatment time of 30 min, the drying time reduced by 28.6%. The contents of polysaccharide and syringin in dried CP slices pretreated by US increased by 14.7% and 62.0%, respectively, compared to the non-pre-treated samples, while the total flavonoid content decreased by 10.0%. In terms of colour, pretreatment had a certain protective effect on the red colour of dried products. The highest relative correlation (0.574) and the best overall quality of performance were observed at 180 W, 60 kHz and 30 min. Overall, US technology is suitable for the pretreatment processing of CP, which is of great significance to the drying of CP.
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Codonopsis , Ultrasonido , Cinética , Desecación/métodos , VacioRESUMEN
In recent years, the wide application of exopolysaccharides (EPSs) in food, cosmetics, medicine, and other fields has drawn tremendous attention. In this study, an EPS produced by Pseudoalteromonas agarivorans Hao 2018 was isolated and purified, and its fermentation conditions were optimized. Its structure and biological functions were also studied. The purity and molecular weight of EPS were determined by high performance liquid chromatography (HPLC), and the EPS exhibited a number average of 2.26 × 105 and a weight average of 2.84 × 105. EPS has good adsorption for Cu2+ and Pb2+. The adsorption rates can reach up to 69.79% and 82.46%, respectively. The hygroscopic property of EPS was higher than that of chitosan, but slightly lower than that of sodium hyaluronate. However, the water-retaining activity of EPS was similar to that of chitosan and sodium hyaluronate. EPS has strong ability to scavenge free radicals, including OH radical and O2- radical. Further, its activity on O2- radicals has similarities with that of vitamin C. EPS has broad application prospects in many fields, such as cosmetics, environmental protection.
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Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/metabolismo , Pseudoalteromonas/metabolismo , Adsorción , Cobre/química , Fermentación , Depuradores de Radicales Libres , Plomo/química , Polisacáridos Bacterianos/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Many marine bacteria secrete exopolysaccharides (EPSs), which are made up of a substantial component of the macro-molecules surrounding cells. Recently, the wide demand for EPSs for food, cosmetics, pharmaceutical and other applications has led to great interest in them. In this study, an EPS produced by marine bacteria Aerococcus uriaeequi HZ strains (EPS-A) was isolated and purified to examine its structure and biological function. The molecular weight of EPS-A analyzed by high-performance liquid gel filtration chromatography (HPGFC) is found to have a number average of 2.22 × 105 and weight average of 2.84 × 105, respectively. High-performance liquid chromatography (HPLC) and Fourier-transformâ»infrared (FTâ»IR) analysis indicate that EPS-A was a polysaccharide composed of glucose and a little mannose. In addition, the flocculating rate of sewage of EPS-A was 79.90%. The hygroscopicity studies showed that hygroscopicity of EPS-A was higher than chitosan but lower than that of sodium hyaluronate. The moisture retention of EPS-A showed similar retention activity to both chitosan and sodium hyaluronate. EPS-A also can scavenge free radicals including both OH⢠free radical and O2â¢- free radical and the activity to O2â¢- free radical is similar to vitamin C. Safety assessment on mice indicated that the EPS-A is safe for external use and oral administration. EPS-A has great potential for applications in medicine due to its characteristics mentioned above.
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Aerococcus/química , Organismos Acuáticos/química , Depuradores de Radicales Libres/farmacología , Polisacáridos Bacterianos/farmacología , Administración Oral , Animales , Cromatografía en Gel , Evaluación Preclínica de Medicamentos , Femenino , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Radicales Libres/metabolismo , Ratones , Peso Molecular , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Toxicidad AgudaRESUMEN
Arctigenin (ARC) is a lignan that is abundant in Asteraceae plants, which show anti-inflammatory and anti-cancer activities. The current study investigated whether ARC affects cancer progression and metastasis, focusing on EMT using invasive human non-small cell lung cancer (NSCLC) cells. No toxicity was observed in the cells treated with different doses of ARC (12-100 µM). The treatment of ARC repressed TGF-ß-stimulated changes of metastatic morphology and cell invasion and migration. ARC inhibited TGF-ß-induced phosphorylation and transcriptional activity of smad2/3, and expression of snail. ARC also decreased expression of N-cadherin and increased expression of E-cadherin in dose-dependent and time-dependent manners. These changes were accompanied by decreased amount of phospho-smad2/3 in nucleus and nuclear translocation of smad2/3. Moreover, ARC repressed TGF-ß-induced phosphorylation of ERK and transcriptional activity of ß-catenin. Our data demonstrate anti-metastatic activity of ARC in lung cancer model.
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Antineoplásicos Fitogénicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Furanos/farmacología , Lignanos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Factor de Crecimiento Transformador beta/metabolismo , Antineoplásicos Fitogénicos/química , Asteraceae/química , Cadherinas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Furanos/química , Humanos , Lignanos/química , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Invasividad Neoplásica/patología , Invasividad Neoplásica/prevención & control , Fosforilación/efectos de los fármacos , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , beta Catenina/metabolismoRESUMEN
To obtain high-quality cherry products, ultrasound (US) combined with five chemical pretreatment techniques were used on cherry prior to radio frequency vacuum drying (RFV), including carboxymethyl cellulose coating (CMC), cellulase (CE), ethanol (EA), isomaltooligosaccharide (IMO), and potassium carbonate + ethyl oleate (PC + AEEO). The effect of different pretreatments (US-CMC, US-CE, US-EA, US-IMO, US-(PC + AEEO)) on the drying characteristics, quality properties, texture, and sensory evaluation of cherries was evaluated. Results showed that the dehydration time and energy consumption were decreased by 4.17 - 20.83 % and 3.22 - 19.34 %, respectively, and the contents of individual sugars, soluble solid, total phenolics (TPC), natural active substances, total flavonoids (TFC), and antioxidant properties (DPPH, ABTS and FRAP) were significantly increased after US combined with five chemical treatments (P < 0.05). Moreover, the pretreatment played important role in improving texture properties and surface color retention in the dried cherries. According to the sensory evaluation analysis, the dehydrated cherries pretreated with US-CMC exhibited the highest overall acceptance, texture, crispness, color, and sweet taste showed lower off-odor, bitter taste and sour taste compared to control and other pretreatments. The findings indicate that US-CMC pretreatment is a promising technique for increasing physicochemical qualities and dehydration rate of samples, which provides a novel strategy to processing of dried cherry.
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Desecación , Prunus avium , Vacio , Desecación/métodos , Prunus avium/química , Ondas Ultrasónicas , Antioxidantes/química , Ondas de Radio , Manipulación de Alimentos/métodos , Calidad de los Alimentos , Gusto , Fenoles/análisis , Fenoles/químicaRESUMEN
Ascorbic acid (AA), which plays a vital role in the metabolism of the human body, is closely correlated with various diseases, including rheumatoid arthritis, scurvy, Parkinson's disease, urinary stones, and diarrhea. The detection of AA is of great significance for early prevention and diagnosis of related diseases. In this paper, a high-performance photoelectrochemical (PEC) sensor was constructed based on cadmium sulfide-gold (CdS-Au) composite nanomaterials for ultrasensitive ascorbic acid (AA) detection. Due to the localized surface plasmon resonance (LSPR) effect of gold nanoparticles (AuNPs), the PEC performance of CdS-Au composite nanomaterials was significantly improved compared to CdS semiconductor nanomaterials. Under the optimal conditions, the AA concentration was linearly related to the photocurrent signal in the range of 0.01 µM-200 µM, with the detection limit being 0.2 nM (S/N = 3) and the sensitivity being 642.9 µA mM-1 cm-2. In addition, the mechanism of the PEC sensor based on CdS-Au composite nanomaterials for ultrasensitive AA detection was discussed. Lastly, the self-constructed PEC sensors have been successfully applied in detecting AA in vitamin C tablets and actual blood samples, meeting the detection criteria required by the Chinese Pharmacopoeia (CP, 2020 edition). The self-fabricated PEC sensors in this paper are expected to be used for quality assessment of AA-related drugs and diagnosis of relevant diseases.
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Nanopartículas del Metal , Nanoestructuras , Humanos , Resonancia por Plasmón de Superficie , Oro , Ácido AscórbicoRESUMEN
In this research, the objective was to optimize the drying process of Astragalus by investigating the effects of microwave vacuum drying parameters, including temperature (30, 35, 40, 45, and 50 °C) and slice thickness (2, 3, 4, 5, and 6 mm). In addition, utilizing COMSOL 6.0 finite element analysis software, we delved into the distribution of heat and moisture during the drying process. The results revealed that drying temperature played a significantly greater role than slice thickness in determining the drying dynamics. The thermal and mass transfer mechanism indicated that the whole drying process conforms to the microwave radiation mechanism and the basic principle of electromagnetic heating. In the case of low temperatures and thinner slice sizes, the more polysaccharide content was retained; The total phenol content peaked when the slice thickness was 5 mm; The increase of slice thickness was not conducive to the retention of total flavonoids content. The potent antioxidant capacity was detected at a temperature of 40 °C, with slice thickness having a negligible effect on this capacity; Low temperatures were beneficial for the preservation of active ingredients. Compared with the scanning electron microscope, the structure appeared more uniform at a temperature of 50 °C. Based on the analysis of the kinetic characteristics of microwave vacuum drying of Astragalus and the quality achieved under various drying conditions, the results of the study can provide valuable guidance for controlling the quality of microwave vacuum drying of Astragalus under different drying requirements.
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Microemulsion is usually a transparent and isotropic liquid mixture composed of oil phase, water phase, surfactant and cosurfactant. The surfactant-framed nanoscale droplets in the microemulsion can penetrate into the skin surface to reduce its barrier function. This makes microemulsion an ideal preparation for the transdermal drug delivery. The permeability of microemulsion may be further enhanced when botanical essential oils that can dissolve the stratum corneum are used as the oil phase. However, the volatility of essential oils is possible to shorten the retention time of the microemulsion on the skin surface. Therefore, analytical methods are required to understand the volatilization process of the microemulsion composed of essential oils to develop the reasonable topical drug carrier system. In this research, Fourier transform infrared (FTIR) spectroscopy with an attenuated total reflection (ATR) accessory cooperated with two-dimensional correlation spectroscopy (2DCOS) to elucidate the volatilization processes of some microemulsions composed of peppermint essential oil. Principal component analysis (PCA) and moving-window two-dimensional correlation spectroscopy (MW2DCOS) revealed the multiple stages of the volatilization processes of the microemulsions. Synchronous 2D correlation infrared spectra indicated the compositional changes during each stage. It was found that the successive volatilizations of ethanol, water and menthone were the major events during the volatilization process of the microemulsion composed of peppermint essential oil. Ethanol can accelerate the volatilization of water, while the composite herbal extract seemed to not influence the volatilization of the other ingredients. After a 20-min-long volatilization process, the remaining microemulsion still contained considerable peppermint essential oil to affect the skin. The above results showed the feasibility of developing the microemulsion composed of peppermint essential oil for the transdermal drug delivery of composite herbal extract. This research also proved that the combination of ATR-FTIR spectroscopy and 2DCOS was valuable to study the volatilization process of the microemulsion.
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Aceites Volátiles , Volatilización , Mentha piperita , Tensoactivos/química , Agua/química , Etanol , Emulsiones/químicaRESUMEN
To maximally maintain fruits and vegetables quality after harvest, this study used ultrasonic (US) and ultra-high pressure (UHP) techniques as pretreatments for radio frequency vacuum (RFV) drying of peach slices, and investigated the effects of different pretreatments (US, UHP, UHP-US, and US-UHP) on drying characteristics, physicochemical qualities, texture properties, and sensory evaluation of peach slices. Results showed that the drying rate was increased by 15.79 â¼ 54.39 % and the contents of pectin, hemicellulose, total phenolic, total flavonoid, phenolic acids, individual sugar annd antioxidant of the samples were significantly increased after US combined with UHP pretreatment (P < 0.05). US-UHP + RFV dried peach slices obtained brighter color, better texture attributes of hardness, cohesiveness, chewiness, springiness, and resilience. The dehydrated samples pretreated by UHP-US had the best overall acceptance, appearance, and crispness with lower off-odor and sourness compared to the dehydrated peach slices with US and UHP pretreatment. Notably, the highest cellulose and organic acids were found in dehydrated peach slices by control, followed by samples US, and samples with UHP pretreatment. The microstructure showed that the internal organization of peach slices appeared as uniform and regular honeycomb porous structure after US-UHP pretreatment. The findings may provide theoretical reference for the development of energy-efficient and high-quality drying technology for fruits and vegetables.
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Prunus persica , Vacio , Desecación/métodos , Antioxidantes/química , Fenoles/análisisRESUMEN
This study employed segmented variable-frequency ultrasound synergistic hot-air drying (SVFU-HAD) for Rhubarb slices, selected two sets of time nodes for frequency conversion (60 min, 120 min, and 90 min, 150 min), and two sequences of frequency conversion (high-frequency to low-frequency, and low-frequency to high-frequency). It aimed to investigate the effects of SVFU-HAD on the drying characteristics, quality, and heat transfer of Rhubarb slices. The findings indicated that segmented variable-frequency ultrasound has advantages in increasing drying rate and improving uniformity of cavitation effects compared to constant-frequency ultrasound. Analysis of physical properties revealed that the rehydration performance of dried products subjected to ultrasonic variable-frequency treatment (90 min, 150 min) according to the drying rate was better (RR > 3.3). The transition mode from high-frequency to low-frequency in variable-frequency ultrasonic treatment contributes to maintaining the overall color of Rhubarb. Analysis of chemical properties unveiled that Rhubarb treated with 40 kHz (0 min)-28 kHz (60 min)-25 kHz (120 min) segmented variable-frequency ultrasound contained overall higher levels of tannins, dianthrones and free anthraquinones content, which exceeded the average values by 3.24%, 26.65%, and 14.42%, respectively. In addition, thermal analysis results based on ANSYS Workbench software demonstrated that the drying uniformity of SVFU-HAD is superior to that of hot-air drying and constant-frequency ultrasound synergistic hot-air drying (CFU-HAD). Overall, the SVFU-HAD method employed in this study presents an innovative approach to ultrasound synergistic hot-air drying research with promising potential for enhancing the efficiency and quality characteristics of Rhubarb slices.
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Desecación , Calor , Rheum , Rheum/química , Desecación/métodos , Aire , Ondas UltrasónicasRESUMEN
To address the challenges associated with prolonged traditional hot air drying (HAD) times and significant nutrient loss in cherries, this study employs ultrasound-assisted hot air drying (USA-HAD) technology. The study investigates the impacts of various ultrasound (US) frequencies, US powers, and hot air temperatures on the drying kinetics, physicochemical properties, texture attributes, and microstructure of cherries during drying. Cherry physicochemical quality serves as the evaluation criterion, with the entropy-weighted TOPSIS method used to identify the optimal drying parameters. The findings indicate that USA-HAD accelerates the drying process, reduces drying time, and enhances drying efficiency. In comparison to natural drying, USA-HAD significantly preserves polysaccharides, total phenolic content, total flavonoid content, and organic acids in cherries, while boosting antioxidant activity. Concurrently, it reduces color intensity, as well as the hardness, chewiness, and gumminess of dried cherry products. Microstructural observations under different drying methods reveal an increase in surface micropores and relatively intact tissue structure. Under conditions of 55°C, 48 W, and 28 kHz, cherries exhibit superior overall quality based on the TOPSIS relative closeness degree. This study offers practical insights for optimizing post-harvest processing of cherries. PRACTICAL APPLICATION: In this rapidly evolving era, the application of combination drying technology is clearly on the rise. The USA-HAD treated cherries had better nutritional and bioactive than HAD. The conclusions obtained indicate that the USA-HAD technology has more potential for development.
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By using ultrasonic synergy vacuum far-infrared drying (US-VFID), the effects of different conditions on the drying kinetics, functional properties, and microstructure of Codonopsis pilosula slices were studied. The sparrow search algorithm (SSA) was used to optimize the back-propagation (BP) neural network to predict the moisture ratio during drying. With the increase of ultrasonic frequency, power and radiation temperature, the drying time of C. pilosula was shortened. The drying time of US-VFID was 25% shorter than VFID, when radiation temperature was 50°C, ultrasonic power was 48 W, and frequency was 28 kHz. The SSA-BP neural network, the average absolute error prediction was 0.0067. Compared with hot air drying (HAD), the total phenolic content and antioxidant activity of C. pilosula by US-VFID were increased by 29.47% and 8.67%, respectively, and a reduction in color contrast of 16.19%. The dilation and generation of microcapillary of C. pilosula were more obvious. The study revealed US-VFID could be used for the selection and process control of agro-processing methods for C. pilosula products.
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Codonopsis , Ultrasonido , Vacio , Codonopsis/química , Temperatura , Antioxidantes/químicaRESUMEN
To fully leverage the advantages of both hot air drying and radio frequency vacuum drying, a segmented combination drying technique was applied to post-harvest Cistanche. This new drying method involves using hot air drying in the initial stage to remove the majority of free water, followed by radio frequency vacuum drying in the later stage to remove the remaining small amount of free water and bound water. During the radio frequency vacuum drying (RFV) phase, the effects of temperature (45, 55, and 65 °C), vacuum pressure (0.020, 0.030, and 0.040 MPa), plate spacing (65, 75, and 85 mm), and slice thickness (4, 5, and 6 mm) on the drying characteristics, quality, and microstructure of Cistanche slices were investigated. Additionally, infrared thermal imaging technology was used to examine the surface temperature distribution of the material during the drying process. The results showed that compared to radio frequency vacuum drying alone, the hot air-radio frequency combined drying significantly shortened the drying time. Under conditions of lower vacuum pressure (0.020 MPa), plate spacing (65 mm), and higher temperature (65 °C), the drying time was reduced and the drying rate increased. Infrared thermal imaging revealed that in the early stages of hot air-radio frequency vacuum combined drying, the center temperature of Cistanche was higher than the edge temperature. As drying progressed, the internal moisture of the material diffused from the inside out, resulting in higher edge temperatures compared to the center and the formation of overheating zones. Compared to natural air drying, the hot air-radio frequency vacuum combined drying effectively preserved the content of active components such as polysaccharides (275.56 mg/g), total phenols (38.62 mg/g), total flavonoids (70.35 mg/g), phenylethanoid glycosides, and iridoids. Scanning electron microscopy observed that this combined drying method reduced surface collapse and cracking of the material. This study provides theoretical references for future drying processes of Cistanche.
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This study aims to maximize the post-harvest quality of Moutan Cortex and reduce energy consumption. Radio frequency vacuum (RFV) technology was used to dehydrate Moutan Cortex in this study to investigate the effects of different drying temperatures, plate spacing, and vacuum degree on the drying kinetics, physicochemical quality, and microstructure of Moutan Cortex. The results showed that RFV drying shortened the dehydration time of the Moutan Cortex by 10.71-28.57% and increased the drying rate by 15.79-54.39% compared to hot-air drying. The best color (∆E = 6.08 ± 0.28, BI = 26.97 ± 0.98) and relatively high retention of polysaccharides, total phenolics, total flavonoids, antioxidant properties, paeonol, gallic acid, paeoniflorin, and benzoylpaeoniflorin contents were observed in the dried products of Moutan Cortex at a drying temperature of 50 °C, spacing of 90 mm, and vacuum of 0.025 MPa. Analyzing the microstructure, it was found that RFV drying could effectively inhibit the shrinkage and collapse of the cellular structure, and a regular and loose honeycomb pore structure appeared inside the samples, which contributed to the rapid migration of the internal moisture. This study can provide a theoretical reference basis for the selection and application of industrialized processing methods of high-quality Moutan Cortex.
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Purpureocillium lavendulum is an important biocontrol agent against plant-parasitic nematodes, primarily infecting them with conidia. However, research on the regulatory genes and pathways involved in its conidiation is still limited. In this study, we employed Agrobacterium tumefaciens-mediated genetic transformation to generate 4,870 random T-DNA insertion mutants of P. lavendulum. Among these mutants, 131 strains exhibited abnormal conidiation, and further in-depth investigations were conducted on two strains (designated as #5-197 and #5-119) that showed significantly reduced conidiation. Through whole-genome re-sequencing and genome walking, we identified the T-DNA insertion sites in these strains and determined the corresponding genes affected by the insertions, namely Plhffp and Plpif1. Both genes were knocked out through homologous recombination, and phenotypic analysis revealed a significant difference in conidiation between the knockout strains and the wild-type strain (ku80). Upon complementation of the ΔPlpif1 strain with the corresponding wildtype allele, conidiation was restored to a level comparable to ku80, providing further evidence of the involvement of this gene in conidiation regulation in P. lavendulum. The knockout of Plhffp or Plpif1 reduced the antioxidant capacity of P. lavendulum, and the absence of Plhffp also resulted in decreased resistance to SDS, suggesting that this gene may be involved in the integrity of the cell wall. RT-qPCR showed that knockout of Plhffp or Plpif1 altered expression levels of several known genes associated with conidiation. Additionally, the analysis of nematode infection assays with Caenorhabditis elegans indicated that the knockout of Plhffp and Plpif1 indirectly reduced the pathogenicity of P. lavendulum towards the nematodes. The results demonstrate that Agrobacterium tumefaciens - mediated T-DNA insertion mutagenesis, gene knockout, and complementation can be highly effective for identifying functionally important genes in P. lavendulum.
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Developing efficient electrocatalysts for CO2 reduction to syngas with tunable H2/CO ratios and high total faradaic efficiency is challenging. Herein, we report an effective catalyst composed of in situ reconstructed AgZn3 nanoparticles and Zn nanoplates for syngas synthesis, showing nearly 100% Faraday efficiency to syngas with a tunable H2/CO ratio from 2 : 1 to 1 : 2. Moreover, the in situ electrochemical measurements coupled with theoretical calculations disclose that the Zn site in AgZn3 nanoparticles and the hollow site between Ag and Zn in AgZn3 are the possible active sites for CO and H2 generation, respectively. This work has guiding significance for designing dual site catalysts for CO2 electroreduction to tunable syngas.
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Dióxido de Carbono , Nanopartículas , ZincRESUMEN
The present study aimed to investigate the effect of rotary microwave vacuum drying (RMVD), radio frequency vacuum drying (RFVD), vacuum far infrared drying (VFID), vacuum drying (VD), hot air drying (HD) and natural drying (ND) on the drying characteristics, active ingredients and microstructure of Codonopsis pilosulae slices. Compared with the fitting results of the four models, the Weibull model is the most suitable drying model for Codonopsis. The RFVD and HD color difference values were smaller compared to ND. The effective moisture diffusivity (Deff) under different drying methods was between 0.06 × 10-8 m2/s and 3.95 × 10-8 m2/s. RMVD-dried products had the shortest drying time and retained more active ingredients. The microstructure analysis revealed that the porous structure of RMVD is more favorable for water migration. RMVD is a promising dehydration method for obtaining high-value-added dried Codonopsis products.
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In this paper, the effects of different ultrasonic pretreatment processes on the far-infrared drying characteristics, quality indexes, and microstructure of licorice are evaluated. The results showed that ultrasonic pretreatment, combined with far-infrared drying, significantly reduced the drying time and moisture content of licorice compared with those of the control group. The highest total flavonoid content was obtained at an ultrasound power of 80 W. The total phenolic content (0.686 mg gallic acid equivalent/g) was higher than that in the control group, the increase was 19.4%, and its content was the highest at the sonication frequency of 20 kHz. The antioxidant capacity tended to increase and then decrease with the increase in sonication time, sonication power, and sonication frequency, and was the highest at 30 min of sonication. The soluble sugar content (31.490 mg glucose equivalent/g) was the highest at 30 kHz and 30 min. Observation of the microstructure revealed that the surface structure of the ultrasonic pretreated licorice slices changed significantly, forming more micropore channels, which facilitated the mass heat transfer during the drying process. In conclusion, ultrasonic pretreatment can significantly improve the quality of licorice tablets and significantly reduce the time required for subsequent drying. The combination of pretreatment parameters of 60 W ultrasonic power and 40 kHz ultrasonic frequency for 30 min was found to be an optimal combination of pretreatment parameters; therefore, this study may provide a technical reference for the industrialization of licorice drying.