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Importance: Baseline findings from the China Dialysis Calcification Study (CDCS) revealed a high prevalence of vascular calcification (VC) among patients with end-stage kidney disease; however, data on VC progression were limited. Objectives: To understand the progression of VC at different anatomical sites, identify risk factors for VC progression, and assess the association of VC progression with the risk of cardiovascular events and death among patients receiving maintenance dialysis. Design, Setting, and Participants: This cohort study was a 4-year follow-up assessment of participants in the CDCS, a nationwide multicenter prospective cohort study involving patients aged 18 to 74 years who were undergoing hemodialysis or peritoneal dialysis. Participants were recruited from 24 centers across China between May 1, 2014, and April 30, 2015, and followed up for 4 years. A total of 1489 patients receiving maintenance dialysis were included in the current analysis. Data were analyzed from September 1 to December 31, 2021. Exposures: Patient demographic characteristics and medical history; high-sensitivity C-reactive protein laboratory values; serum calcium, phosphorus, and intact parathyroid hormone (iPTH) values; and previous or concomitant use of medications. Main Outcomes and Measures: The primary outcome was progression of VC at 3 different anatomical sites (coronary artery, abdominal aorta, and cardiac valves) and identification of risk factors for VC progression. Participants received assessments of coronary artery calcification (CAC), abdominal aortic calcification (AAC), and cardiac valve calcification (CVC) at baseline, 24 months, 36 months, and 48 months. Secondary outcomes included (1) the association between VC progression and the risk of all-cause death, cardiovascular (CV)-related death, and a composite of all-cause death and nonfatal CV events and (2) the association between achievement of serum calcium, phosphorus, and iPTH target levels and the risk of VC progression. Results: Among 1489 patients, the median (IQR) age was 51.0 (41.0-60.0) years; 59.5% of patients were male. By the end of 4-year follow-up, progression of total VC was observed in 86.5% of patients; 69.6% of patients had CAC progression, 72.4% had AAC progression, and 33.4% had CVC progression. Common risk factors for VC progression at the 3 different anatomical sites were older age and higher fibroblast growth factor 23 levels. Progression of CAC was associated with a higher risk of all-cause death (model 1 [adjusted for age, sex, and body mass index]: hazard ratio [HR], 1.97 [95% CI, 1.16-3.33]; model 2 [adjusted for all factors in model 1 plus smoking status, history of diabetes, and mean arterial pressure]: HR, 1.89 [95% CI, 1.11-3.21]; model 3 [adjusted for all factors in model 2 plus calcium, phosphorus, intact parathyroid hormone, and fibroblast growth factor 23 levels and calcium-based phosphate binder use]: HR, 1.92 [95% CI, 1.11-3.31]) and the composite of all-cause death and nonfatal CV events (model 1: HR, 1.98 [95% CI, 1.19-3.31]; model 2: HR, 1.91 [95% CI, 1.14-3.21]; model 3: HR, 1.95 [95% CI, 1.14-3.33]) after adjusting for all confounding factors except the presence of baseline calcification. Among the 3 targets of calcium, phosphorus, and iPTH, patients who achieved no target levels (model 1: odds ratio [OR], 4.75 [95% CI, 2.65-8.52]; model 2: OR, 4.81 [95% CI, 2.67-8.66]; model 3 [for this analysis, adjusted for all factors in model 2 plus fibroblast growth factor 23 level and calcium-based phosphate binder use]: OR, 2.76 [95% CI, 1.48-5.16]), 1 target level (model 1: OR, 3.71 [95% CI, 2.35-5.88]; model 2: OR, 3.62 [95% CI, 2.26-5.78]; model 3: OR, 2.19 [95% CI, 1.33-3.61]), or 2 target levels (model 1: OR, 2.73 [95% CI, 1.74-4.26]; model 2: OR, 2.69 [95% CI, 1.71-4.25]; model 3: OR, 1.72 [95% CI, 1.06-2.79]) had higher odds of CAC progression compared with patients who achieved all 3 target levels. Conclusions and Relevance: In this study, VC progressed rapidly in patients undergoing dialysis, with different VC types associated with different rates of prevalence and progression. Consistent achievement of serum calcium, phosphorus, and iPTH target levels was associated with a lower risk of CAC progression. These results may be useful for increasing patient awareness and developing appropriate strategies to improve the management of chronic kidney disease-mineral and bone disorder among patients undergoing dialysis.
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Diálise Renal , Calcificação Vascular , Humanos , Masculino , Feminino , Diálise Renal/efeitos adversos , Fator de Crescimento de Fibroblastos 23 , Estudos de Coortes , Cálcio , Estudos Prospectivos , Calcificação Vascular/epidemiologia , Fatores de Risco , Hormônio Paratireóideo , Fosfatos , FósforoRESUMO
Ascorbic acid (AsA) inhibits wound healing in fresh-cut potatoes (FCP); however, the comprehensive regulatory mechanisms of the chemical during wound healing remain unclear. Here, physiobiochemical, transcriptomic, and metabolomic analyses were performed. In total, 685 differentially expressed genes (DEGs) and 1921 differentially accumulated metabolites (DAMs) were identified between control and AsA-treated samples. The level of the majority of DEGs expression and DAMs abundance in AsA-treated samples were similar to data of newly cut samples. The collective data indicated that the AsA treatment inhibited wound healing in FCPs by regulating glutathione metabolism, enhancing starch metabolism, and inhibiting phenylalanine metabolism, sucrose degradation, and fatty acid synthesis. Major genes and metabolites affected by AsA treatment included StGST, StPAL, StPHO1 and StLOX5, and starch, sucrose, and linoleic acid. AsA treatment increased starch content and amylase and lipoxygenase activity and decreased free fatty acid level. Our research provides fundamental insights into wound healing mechanisms in FCP.
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Solanum tuberosum , Transcriptoma , Ácido Ascórbico/análise , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Perfilação da Expressão Gênica , Cicatrização/genética , Amido/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
The rapid softening of hardy kiwifruit (Actinidia arguta) fruit significantly reduces its marketing potential. Therefore, the effect of 1-methylcyclopropene (1-MCP) on the softening of A. arguta fruit was investigated. Results indicated that A. arguta fruit treated with 1-MCP maintained a higher level of firmness, titratable acidity, ascorbic acid, total phenolics, and flavonoids content, relative to non-treated fruit. Fruit treated with 1-MCP and placed in long-term cold storage had higher sensory scores, as determined by a taste panel and supported by electronic nose and tongue data. Notably, 1-MCP delayed the degradation of cell wall components, including pectin, cellulose, and hemicellulose, by reducing the activity of cell-wall-modifying enzymes. In addition, 1-MCP reduced the activity of carbohydrate metabolism-related enzymes, resulting in fruit with higher levels of starch and sucrose and lower levels of glucose, fructose and sorbitol. Collectively, these results indicate that 1-MCP can be used to delay the softening of A. arguta fruit and extend its storage and shelf life.
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Actinidia , Frutas , Humanos , Frutas/metabolismo , Tempo para o Tratamento , Metabolismo dos Carboidratos , Parede Celular/metabolismoRESUMO
The aim of the present study was to investigate the effects of ethanol vapor on the inhibition of Alternaria alternata and Botrytis cinerea in postharvest blueberry and the induction of defense-related enzymes (DREs) activities in fungi-inoculated blueberries stored at 0±0.5°C for 16days. Results indicated that ethanol vapor markedly inhibited the mycelial growth of A. alternata and B. cinerea in a dose-dependent manner, with inhibition rates of 9.1% (250µlL-1), 36.4% (500µlL-1), and 5.5% (1,000µlL-1) on A. alternata and 14.2% (250µlL-1), 44.7% (500µlL-1), and 76.6% (1,000µlL-1) on B. cinerea, respectively. Meanwhile, ethanol vapor also enhanced the activities of DREs in fungi-inoculated blueberries, including ß-1,3-glucanase (GLU), chitinase (CHI), phenylalnine ammonialyase (PAL), peroxidase (POD), and polyphenol oxidase (PPO). In particular, 500µlL-1 ethanol vapor increased the activities of DREs by 84.7% (GLU), 88.0% (CHI), 37.9% (PAL), 85.5% (POD), and 247.0% (PPO) in A. alternata-inoculated blueberries and 103.8% (GLU), 271.1% (CHI), 41.1% (PAL), 148.3% (POD), and 74.4% (PPO) in B. cinerea-inoculated blueberries, respectively. But, the activity of PPO was decreased by 55.2 and 31.9% in 500µlL-1 ethanol-treated blueberries inoculated with A. alternata and B. cinerea, respectively, after 8days of storage. Moreover, the surface structure and ultrastructure of 500µlL-1 ethanol-treated blueberry fruit cells were more integrated than those of other treatments. The findings of the present study suggest that ethanol could be used as an activator of defense responses in blueberry against Alternaria and Botrytis rots, by activating DREs, having practical application value in the preservation of postharvest fruit and vegetables.
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INTRODUCTION: Radix Paeoniae Alba (RPA) presents several pharmacological effects, including analgesia, liver protection, and toxicity reduction. RPA consists mostly of monoterpenes and their glycosides, tannins, flavonoids, and organic acids, with monoterpenes being the main active pharmaceutical ingredients. OBJECTIVE: To establish an effective method for rapid classification and identification of the main monoterpenes, flavonoids, and organic acids in RPA. METHODS: We used ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and data post-processing technology to rapidly classify and identify the monoterpenoids, flavonoids, and organic acids in RPA. We also summarised the diagnostic product ions and neutral losses of monoterpenoids, flavonoids, and organic acids in RPA reported in the literature. RESULTS: We identified 24 components, namely 18 monoterpenoids, one flavonoid, and five organic acids. CONCLUSION: In this study, we analysed the chemically active pharmaceutical ingredients and assessed the quality of RPA. In addition, we demonstrated that UHPLC-Q-TOF-MS can be used to qualitatively classify and identify the variety of chemical components of traditional Chinese medicines (TCMs) to a certain extent. Moreover, we confirmed that mass spectrometry can be used to identify the components of TCMs.
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Medicamentos de Ervas Chinesas , Paeonia , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de MassasRESUMO
BACKGROUND: Blueberry is universally acknowledged as a kind of berry rich in antioxidants. Cold plasma, an emerging non-thermal treatment technology, has been proved to be able to maintain or improve the antioxidant level while inactivating the microorganisms on the surface of fruits and vegetables. Postharvest blueberries were treated with atmospheric cold plasma (ACP; 12 kV, 5 kHz) for 0 s (Control), 30 s (ACP-30), 60 s (ACP-60), and 90 s (ACP-90) in this study, and the effects of ACP on the antimicrobial properties, antioxidant activities, and reactive oxygen species (ROS) production were investigated during storage at 4 ± 1 °C for 40 days. RESULTS: Total aerobic bacteria and mold populations on ACP-treated blueberries decreased significantly in a time-dependent manner (P < 0.05), and decreased by 0.34-1.24 and 0.57-0.87 log10 CFU g-1 respectively on ACP-60-treated blueberries during storage. The decay rate of blueberries was decreased by 5.8-11.7% and the decrease of blueberry firmness was slowed down by ACP-60. But the total phenol, anthocyanin, and ascorbic acid contents increased, and superoxide dismutase, catalase, and peroxidase activities were enhanced in ACP-treated blueberries. The free radical scavenging activity and total antioxidant capacity (T-AOC) were enhanced. Hydrogen peroxide (H2 O2 ) and superoxide anion (O2 - ) production rates declined by 27.3% and 41.3% at day 40 of storage, respectively. CONCLUSION: It is suggested that ACP may be a promising non-thermal treatment technology for postharvest sterilization and preservation of blueberry under suitable conditions. © 2020 Society of Chemical Industry.
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Antioxidantes/análise , Mirtilos Azuis (Planta)/química , Conservação de Alimentos/métodos , Frutas/efeitos dos fármacos , Gases em Plasma/farmacologia , Antocianinas/análise , Antocianinas/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Bactérias/crescimento & desenvolvimento , Mirtilos Azuis (Planta)/efeitos dos fármacos , Mirtilos Azuis (Planta)/metabolismo , Mirtilos Azuis (Planta)/microbiologia , Catalase/metabolismo , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Frutas/microbiologia , Fungos/crescimento & desenvolvimento , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Fenóis/análise , Fenóis/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismoRESUMO
The main objective of this study was to investigate the effect of low-level light emitting diode (LED) irradiation on the metabolite profile of pak-choi. A total of 633 different molecular features (MFs) were identified among sample groups (initial, dark-treated, light-treated) using an untargeted metabolomic approach. The identified metabolites were associated with 24 different metabolic pathways. Four of the pathways including carbon pool by folate, folate biosynthesis, thiamine metabolism, and glutathione metabolism, all of which are associated with vitamin biosynthesis, changed significantly. Metabolites in four of the pathways exhibited significant differences from the control in response to LED irradiation. Additionally, porphyrin and chlorophyll metabolism, as well as glucosinolate biosynthesis, riboflavin metabolism, and carotenoid biosynthesis were positively induced by LED irradiation. These results indicate that postharvest LED illumination represents a potential tool for modifying the metabolic profile of pak-choi to maintain quality and nutritional levels.
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Brassica/metabolismo , Brassica/efeitos da radiação , Vitaminas/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Metabolômica/métodos , Vitaminas/metabolismoRESUMO
For the full development and utilization of Sophora tonkinensis Gagnep., this study was primarily intended to established a simple and efficient approach for the preparative purification of total flavonoids from S. tonkinensis by macroporous resin column chromatography (MRCC). The adsorption and desorption characteristics of the total flavonoids on ten macroporous resins were first studied, and AB-8 resin was chosen as the most suitable, and the adsorption data were best fitted to the pseudo-second-order kinetics model and Langmuir isotherm model. Furthermore, the technological parameters for the purification of the total flavonoids were optimized using column chromatography. After a sample one-step purification procedure, the content of the total flavonoids increased by about 4.76-fold from 12.14% to 57.82%, with a recovery yield of 84.93%. In addition, the comparative analysis of the flavonoid extracts before and after purification was performed by high-performance liquid chromatography coupled with photodiode-array detection (HPLC-PAD). The results showed that the contents of six major flavonoids in the purified product were all higher than before the purification. Therefore, the AB-8 MRCC established in this work was a promising method for the industrial-scale purification of the total flavonoids from S. tonkinensis.
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Flavonoides/química , Extratos Vegetais/química , Resinas Vegetais/química , Sophora/química , Cromatografia Líquida de Alta PressãoRESUMO
BACKGROUND: Blueberries are appreciated by consumers for their rich natural antioxidants and their good nutritional and health functions. However, blueberries are very perishable due to microbial infection and metabolic aging after harvest. Ethanol has been shown to have the effect of controlling postharvest microorganisms and improving storage quality of fruits and vegetables. This study aimed to clarify the effects of ethanol on the appearance quality and flavor attributes of postharvest blueberries. Blueberries were treated with ethanol (250, 500, and 1000 µL L-1 ) and stored at 0 ± 0.5 °C, 90% relative humidity (RH), for 40 days. RESULTS: The results indicated that ethanol treatment could slow the decline of blueberry firmness and reduce the decay rate significantly in a dose-dependent manner. The soluble solids content (SSC) and titratable acidity (TA) of ethanol-treated blueberries increased significantly (P < 0.05), improving the taste of the blueberries. The activities of alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC) were stimulated with the accumulation of ethanol in blueberries, which catalyzed the conversion of ethanol, acetaldehyde, and pyruvate, increasing their levels in blueberries. More volatiles, especially esters, were detected in ethanol-treated blueberries, e.g. methyl acetate, ethyl acetate, ethyl propanoate, ethyl isobutyrate, ethyl 2-methylbutanoate, ethyl isovalerate, ethyl 3-methyl-2-butenoate, diethyl sebacate, and isopropyl myristate. CONCLUSION: The preservative effect of ethanol on blueberry was significantly affected by ethanol concentration. In this study, the effect of 500 µL L-1 ethanol fumigation on blueberry was the best in terms of appearance quality (firmness and decay rate) and flavor attributes (SSC, TA, and volatiles). © 2019 Society of Chemical Industry.
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Mirtilos Azuis (Planta)/química , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/efeitos dos fármacos , Mirtilos Azuis (Planta)/efeitos dos fármacos , Frutas/química , Fumigação/métodos , Humanos , Controle de Qualidade , Paladar , Compostos Orgânicos Voláteis/análiseRESUMO
OBJECTIVE: With limited data available on calcification prevalence in chronic kidney disease (CKD) patients on dialysis, the China Dialysis Calcification Study (CDCS) determined the prevalence of vascular/valvular calcification (VC) and association of risk factors in Chinese patients with prevalent hemodialysis (HD) or peritoneal dialysis (PD). METHODS: CKD patients undergoing HD/PD for ≥6 months were enrolled. Prevalence data for calcification and medical history were documented at baseline. Coronary artery calcification (CAC) was assessed by electron beam or multi-slice computed tomography (EBCT/MSCT), abdominal aortic calcification (AAC) by lateral lumbar radiography, and cardiac valvular calcification (ValvC) by echocardiography. Serum phosphorus, calcium, intact parathyroid hormone (iPTH), and 25-hydroxyvitamin D and FGF-23 were evaluated. A logistic regression model was used to evaluate the association between risk factors and VC. RESULTS: Of 1,497 patients, 1,493 (78.3% HD, 21.7% PD) had ≥1 baseline calcification image (final analysis cohort, FAC) and 1,423 (78.8% HD, 21.2% PD) had baseline calcification data complete (BCDC). Prevalence of VC was 77.4% in FAC (80.8% HD, 65.1% PD, p < .001) and 77.5% in BCDC (80.7% HD, 65.8% PD). The proportion of BCDC patients with single-site calcification were 20% for CAC, 4.3% for AAC, and 4.3% for cardiac valvular calcification (ValvC), respectively. Double site calcifications were 23.4% for CAC and AAC, 6.5% for CAC and ValvC, and 1.1% for AAC and ValvC, respectively. In total, 17.9% patients had calcification at all three sites. CONCLUSIONS: High prevalence of total VC in Chinese CKD patients will supplement current knowledge, which is mostly limited, contributing in creating awareness and optimizing VC management.
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Diálise Renal , Insuficiência Renal Crônica/complicações , Calcificação Vascular/epidemiologia , Adulto , Idoso , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Insuficiência Renal Crônica/terapia , Fatores de Risco , Tomografia Computadorizada por Raios X , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etiologiaRESUMO
In this study, the effects of oligochitosan treatment on controlling postharvest diseases in Dongxue peach ( Prunus Persica L. Batsch, cv Dongxuemi) were examined and the possible underlying mechanisms were discussed. Results showed that the disease incidence and lesion area in peach fruit inoculated with Monilinia fructicola and Penicillium expansum were all remarkably reduced by oligochitosan treatment. Oligochitosan treatment inhibited spore germination and mycelial growth of the two fungi in vitro. Oligochitosan treatment also induced upregulation of the salicylic acid signalling pathway-related genes (NPR1, PR1 and phenylalanine ammonia lyase) and enhanced the levels of total phenolics, flavonoids and lignin in peach. Meanwhile, enzymatic activities of superoxide dismutase, catalase, polyphenoloxidase, ascorbate peroxidase and phenylalanine ammonia lyase also increased. These findings suggest that the effects of oligochitosan on the disease control of peach fruit may be associated with its direct antimicrobial effects as well as increasing antioxidant, phenylpropanoid metabolism and accumulating antifungal compounds by activating the salicylic acid-dependent pathway.
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Ascomicetos/efeitos dos fármacos , Quitina/análogos & derivados , Conservantes de Alimentos/farmacologia , Frutas/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Penicillium/efeitos dos fármacos , Prunus persica/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , China , Quitina/efeitos adversos , Quitina/farmacologia , Quitosana , Produtos Agrícolas/química , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Flavonoides/metabolismo , Conservantes de Alimentos/efeitos adversos , Qualidade dos Alimentos , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/microbiologia , Fungicidas Industriais/efeitos adversos , Lignina/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Micélio/isolamento & purificação , Micélio/metabolismo , Oligossacarídeos , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Penicillium/crescimento & desenvolvimento , Penicillium/isolamento & purificação , Penicillium/metabolismo , Fenóis/metabolismo , Proteínas de Plantas/metabolismo , Prunus persica/crescimento & desenvolvimento , Prunus persica/metabolismo , Prunus persica/microbiologia , Transdução de Sinais , Esporos/efeitos dos fármacos , Esporos/crescimento & desenvolvimento , Esporos/isolamento & purificação , Esporos/metabolismoRESUMO
BACKGROUND: Food preservation is critical for keeping fresh-cut products fresh, nutritious, safe, attractive and available for consumers. To improve the safety and quality of fresh-cut fruits, 15 essential oils (EOs) were screened to test the antimicrobial activity against Listeria monocytogenes (LM), Salmonella typhimurium (ST), Staphylococcus aureus (SA) and Escherichia coli O157:H7 (EC O157:H7). The effect of alginate-based edible coating (EC) incorporating different concentrations thyme oil on fresh-cut 'Red Fuji' apples was investigated. RESULTS: Results showed that thyme oil, cinnamon oil and oregano oil were more effective in inhibiting the microbes than other EOs. The result showed that the combined usage of 0.5 µL mL-1 thyme oil incorporated with alginate-based EC could significantly inhibit the microbial growth, respiration, weight loss, firmness and browning of fresh-cut 'Red Fuji' apples. CONCLUSION: The edible coating and natural additives like thyme oil could be used to preserve the quality of fresh-cut fruits. It revealed that EC incorporated with 0.5 µL mL-1 thyme oil can be a safe preservative for fresh-cut apples. © 2017 Society of Chemical Industry.
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Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Malus/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Thymus (Planta)/química , Alginatos/química , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Contaminação de Alimentos/prevenção & controle , Conservantes de Alimentos/química , Frutas/química , Frutas/microbiologia , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Malus/microbiologia , Óleos Voláteis/química , Óleos de Plantas/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Vapours of organic matters were determined qualitatively employed with ultraviolet-visible absorption spectroscopy. Vapours of organic matters were detected using ultraviolet-visible spectrophotometer employing polyethylene film as medium, the ultraviolet and visible absorption spectra of vegetable oil vapours of soybean oil, sunflower seed oil, peanut oil, rapeseed oil, sesame oil, cotton seed oil, tung tree seed oil, and organic compound vapours of acetone, ethyl acetate, 95% ethanol, glacial acetic acid were obtained. Experimental results showed that spectra of the vegetable oil vapour and the organic compound vapour could be obtained commendably, since ultra violet and visible spectrum of polyethylene film could be deducted by spectrograph zero setting. Different kinds of vegetable oils could been distinguished commendably in the spectra since the λ(max), λ(min), number of absorption peak, position, inflection point in the ultra violet and visible spectra obtained from the vapours of the vegetable oils were all inconsistent, and the vapours of organic compounds were also determined perfectly. The method had a good reproducibility, the ultraviolet and visible absorption spectra of the vapours of sunflower seed oil in 10 times determination were absolutely the same. The experimental result indicated that polyethylene film as a kind of medium could be used for qualitative analysis of ultraviolet and visible absorption spectroscopy. The method for determination of the vapours of the vegetable oils and organic compounds had the peculiarities of fast speed analysis, well reproducibility, accuracy and reliability and low cost, and so on. Ultraviolet and visible absorption spectrum of organic vapour could provide feature information of material vapour and structural information of organic compound, and provide a novel test method for identifying vapour of compound and organic matter.
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Gases/análise , Óleos de Plantas/química , Espectrofotometria Ultravioleta , Óleo de Sementes de Algodão , Ácidos Graxos Monoinsaturados , Óleo de Amendoim , Polietilenos , Óleo de Brassica napus , Reprodutibilidade dos Testes , Sementes , Óleo de Gergelim , Óleo de Soja , Óleo de GirassolRESUMO
BACKGROUND: Fresh-cut eggplants, as other vegetables, have relatively short shelf life because of the large amount of tissue disruption and increased metabolism. There is a very rapid onset of enzymatic browning and tissue softening with consequent decrease in sensorial and nutritional quality. To reduce respiration and maintain the quality, various treatments have been applied to find the optimum conditions that provide more fresh and natural fresh-cut produce after minimal processing. The objective of this study was to investigate the effects of ethanol vapour treatment on physiological and quality attributes of fresh-cut eggplant during the extension of shelf life. RESULTS: The fresh-cut eggplant treated with ethanol vapour showed that respiration rate and occurrence of enzymatic browning were reduced, and higher total phenol content was maintained during 8 days of storage at 10 degrees C. The polyphenol oxidase and peroxidase in fresh-cut eggplant were also inhibited significantly by ethanol treatment. The ethanol treatment reduced the weight loss and maintained the integrity of cell membranes, as confirmed by the low value of electrolyte leakage. CONCLUSION: The ethanol treatment applied for fresh-cut eggplant was a practical approach to reduce the activity of physiological metabolism and maintain the fresh quality of fresh-cut eggplant. The experimental results revealed that ethanol treatment was effective for extending the shelf life of fresh-cut eggplant as a cheap, environmentally acceptable method.