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1.
J Food Sci ; 84(8): 2121-2127, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31269247

RESUMEN

The effects of thermal oxidation at 65 °C for 24 days on oxidation indices, fatty acid positional distribution, thermal properties, vitamin E composition and sterol composition of kenaf seed oil are investigated. The results showed that total oxidation value (TOTOX) of the oil increased from initial 8.83 to 130.74 at the end of 24 days storage. Linoleic acid at sn-1, 3 positon of kenaf seed oil was less stable than the one at sn-2 positon. Oxidative degradation changed the melting profile of kenaf seed oil, the value of endothermic enthalpy reduced from 58.17 to 20.25 J/g after 24 days of storage. Moreover, the content of vitamin E and total sterol decreased by 84.26% and 38.47%, respectively. Tocotrienols were more stable than tocopherols during the accelerated storage. Correlation analysis indicated vitamin E content was significantly related to p-anisidine value, while sterol content was significantly related to peroxide value. PRACTICAL APPLICATION: Kenaf seed oil is rich in polyunsaturated fatty acids and bioactive compounds. Heating process and long-term storage cause oil oxidation and bioactive compounds degradation. The oxidation process of kenaf seed oil is simulated with accelerated storage. The study evaluates fatty acid composition and distribution, vitamin E and sterol content, melting thermal characteristics of kenaf seed oil at different oxidation levels. The research shows the stability of fatty acid is related with its type and position in backbone of triacylglycerol molecule. There are good correlation among oxidation level, vitamin E and sterol content, and melting enthalpy value of kenaf seed oil.


Asunto(s)
Ácidos Grasos/química , Hibiscus/química , Aceites de Plantas/química , Almacenamiento de Alimentos , Calor , Ácido Linoleico/análisis , Oxidación-Reducción , Semillas/química , Tocoferoles/análisis , Tocotrienoles/análisis , Triglicéridos/análisis , Vitamina E/análisis
2.
Appl Radiat Isot ; 139: 224-230, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29852404

RESUMEN

Fungal infection is inevitable in the cultivation and storage process of soybean. Gamma irradiation is an effective method to control fungal growth and inactivate mycotoxins. The effects of gamma irradiation and fungal damage on the number of fungi, aflatoxin B1 content, proximate composition of soybeans, and quality of soybean oil (acid value, peroxide value, iodine value, fatty acid profile, tocopherols content, and oxidation stability) were investigated in this work. Growth of fungi caused some changes in proximate composition of soybean and qualities of soybean oil. However, the changes depended on the damage extent of soybeans. No significant change was found for the soybeans incubated for 30 days (moderately fungi-damaged). Gamma irradiation could completely eliminate the fungi and greatly reduce the content of aflatoxin B1 in soybeans at 10 kGy. For soybeans incubated for 30 days, there were no significant changes in the quality attributes, tocopherols content and oxidation stability of oil when the gamma irradiation dose was less than 20 kGy. Gamma irradiation is a promising method to improve the safety and economy of moderately fungi-damaged soybean used for feedstuff.


Asunto(s)
Aflatoxina B1/análisis , Aflatoxina B1/efectos de la radiación , Irradiación de Alimentos/métodos , Glycine max/química , Glycine max/efectos de la radiación , Aceite de Soja/química , Aceite de Soja/efectos de la radiación , Ácidos Grasos/análisis , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Hongos/aislamiento & purificación , Hongos/efectos de la radiación , Rayos gamma/uso terapéutico , Humanos , Oxidación-Reducción , Tocoferoles/análisis
3.
J Oleo Sci ; 67(3): 255-263, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29459511

RESUMEN

Supercritical carbon dioxide extraction (SC-CO2) technology was used to extract oil from Eucommia ulmoides seed. The optimum conditions and significant parameters in SC-CO2 were obtained using response surface methodology (RSM). The qualities of the extracted oil were evaluated by physicochemical properties, fatty acid composition, vitamin E composition. It was found that the optimum extraction parameters were at pressure of 37 MPa, temperature of 40°C, extraction time of 125 min and CO2 flow rate of 2.6 SL/min. Pressure, temperature and time were identified as significant parameter effecting on extraction yield. The importance of evaluated parameters decreased in the order of pressure > extraction time > temperature > CO2 flow rate. GC analysis indicated that E. ulmoides seed oil contained about 61% of linolenic acid and its fatty acid composition was similar with that of flaxseed oil and perilla oil. The content and composition of vitamin E was determined using HPLC. The E. ulmoides seed oil was rich in vitamin E (190.72 mg/100 g), the predominant vitamin E isomers were γ- tocopherol and δ- tocopherol, which accounted for 70.87% and 24.81% of the total vitamin E, respectively. The high yield and good physicochemical properties of extracted oil support the notion that SC-CO2 technology is an effective technique for extracting oil from E. ulmoides seed.


Asunto(s)
Cromatografía con Fluido Supercrítico/métodos , Eucommiaceae/química , Calidad de los Alimentos , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Semillas/química , Dióxido de Carbono , Fenómenos Químicos , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Ácidos Grasos/análisis , Presión , Temperatura , Factores de Tiempo , Vitamina E/análisis , Ácido alfa-Linolénico/análisis
4.
J Food Sci ; 83(3): 617-623, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29355957

RESUMEN

Eucommia ulmoides seed oil is the main byproduct of E. ulmoides cultivation. To better understand its functions, E. ulmoides seed oil is characterized comprehensively in this work. The composition of E. ulmoides seed, physicochemical properties, thermal properties, fatty acid composition, triacylglycerol (TAG) composition and Vitamin E composition of E. ulmoides seed oil were determined. The results show that the E. ulmoides seed contained about 34.63% oil. The excellent physicochemical properties of E. ulmoides seed oil ensured it has a potential to be developed as an edible oil. The main fatty acids in E. ulmoides seed oil were linolenic acid (61.36%), oleic acid (17.02%), and linoleic acid (12.04%). HPLC-ELSD method determined that LnLnLn (37.99%), LnLnO (22.62%), LnLnL (14.5%), and LnLnP (8.78%) were the oil's major TAG components. The oil exhibited a unique thermal curve which contained 2 melting peaks at -38.45 and -22.22 °C, respectively. The total content of vitamin E in E. ulmoides seed oil was 190.96 mg/100g, which exist mainly in γ-tocopherol and δ-tocopherol isomer. Overall, the results indicated that E. ulmoides seed oil is a promising oil in food, pharmaceutics, cosmetics and other nonfood industries.


Asunto(s)
Eucommiaceae/química , Aceites de Plantas/química , Ácido alfa-Linolénico/química , Cromatografía Líquida de Alta Presión , Ácidos Grasos/química , Ácido Linoleico/análisis , Ácido Oléico/análisis , Semillas/química , Tocoferoles/análisis , Triglicéridos/análisis , Vitamina E/análisis , gamma-Tocoferol/análisis
5.
Pest Manag Sci ; 71(3): 404-14, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24777582

RESUMEN

BACKGROUND: Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with broad spectrum and high activity, a series of novel oxime ether strobilurin derivatives containing substituted benzofurans in the side chain were synthesised and bioassayed. RESULTS: The synthesised compounds were characterised by (1) H NMR, (13) C NMR, MS and HRMS. Bioassays demonstrated that most target compounds possessed good or excellent fungicidal activities, especially against Erysiphe graminis and Pyricularia oryzae. Furthermore, methyl 3-methoxypropenoate oxime ethers exhibited remarkably higher activities against E. graminis, Colletotrichum lagenarium and Puccinia sorghi Schw. Notably, (E,E)-methyl 3-methoxy-2-{2-[({[5-fluoro-1-(benzofuran-2-yl)ethylidene]amino}oxy)methyl]phenyl}propenoate (BSF2) and (E,E)-methyl 3-methoxy-2-{2-[({[5-chloro-1-(benzofuran-2-yl)ethylidene]amino}oxy)methyl]phenyl}propenoate (BSF3) were identified as the most promising candidates for further study. CONCLUSION: The present work demonstrates that oxime ether strobilurin derivatives containing benzofurans can be used as possible lead compounds for developing novel fungicides.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Fungicidas Industriales/síntesis química , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Fungicidas Industriales/farmacología , Espectroscopía de Resonancia Magnética , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/farmacología , Oximas/síntesis química , Oximas/química , Oximas/farmacología , Relación Estructura-Actividad
6.
Chem Biol Drug Des ; 85(6): 743-55, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25346294

RESUMEN

Twenty-one novel oxime ether strobilurins containing indole moiety, which employed an indole group to stabilize the E-styryl group in Enoxastrobin, were designed and synthesized. The biological assay indicated that most compounds exhibited potent fungicidal activities. The structure-activity relationship study demonstrated that the synthesized methyl 3-methoxypropenoate oxime ethers 7b-e exhibited remarkably high activities among all the synthesized oxime ether compounds 7. Moreover, the fungicidal activities of methyl α-(methoxyimino)benzeneacetate oxime ethers compounds 7f-i and N-methoxy-carbamic acid methyl esters compounds 7j-m showed significant differences compared to the corresponding products of ammonolysis.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Indoles/química , Oximas/química , Éteres/síntesis química , Éteres/química , Éteres/farmacología , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Fungicidas Industriales/síntesis química , Fungicidas Industriales/farmacología , Indoles/síntesis química , Indoles/farmacología , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/farmacología , Oximas/síntesis química , Oximas/farmacología , Estrobilurinas , Relación Estructura-Actividad
7.
Bioorg Med Chem Lett ; 24(9): 2173-6, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24717155

RESUMEN

Twenty-one novel benzothiophene-substituted oxime ether strobilurins, which employed a benzothiophene group to stabilise the E-styryl group in Enoxastrobin (an unsaturated oxime strobilurin fungicide developed by Shenyang Research Institute of Chemical Industry, China) were designed and synthesised. The biological assay indicated that most compounds exhibited good or excellent fungicidal activities, especially against Colletotrichum lagenarium and Puccinia sorghi Schw. In addition, methyl 3-methoxypropenoate oxime ethers and N-methoxy-carbamic acid methyl esters exhibited good in vivo fungicidal activities against Erysiphe graminis, Colletotrichum lagenarium and Puccinia sorghi Schw. under the tested concentrations. Notably, (E,E)-methyl 3-methoxy-2-(2-((((6-chloro-1-(1H-benzo[b]thien-2-yl)ethylidene)amino)oxy)methyl)phenyl)propenoate (5E) exhibited more potent in vivo fungicidal activities against nearly all of the tested fungi at a concentration of 0.39 mg/L compared to Enoxastrobin.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Fungicidas Industriales/toxicidad , Tiofenos/química , Tiofenos/toxicidad , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/toxicidad , Fungicidas Industriales/síntesis química , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/toxicidad , Oximas/síntesis química , Oximas/química , Oximas/toxicidad , Estrobilurinas , Tiofenos/síntesis química
8.
Colloids Surf B Biointerfaces ; 111: 252-6, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23831592

RESUMEN

Biofilms can adhere to most surfaces and have caused a wide range of problems in various industrial processes as well as daily life activities. In this work, the anti-biofilm ability of Nafion-coated stainless steel surface was investigated and our results showed that stainless steel discs coated with 1% Nafion can significantly reduce E. coli adhesion. Nafion has a large amount of negatively charged sulphonate groups, and the findings of this study suggest that the negative surface charge can greatly reduce bacterial adhesion through increasing the electrostatic repulsion between negatively charged bacterial cells and Nafion coated stainless steel surface. The roughness of coated and uncoated stainless steel discs made no significant differences while the hydrophobic of the discs increased after coated with Nafion.


Asunto(s)
Biopelículas/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/fisiología , Polímeros de Fluorocarbono/farmacología , Acero Inoxidable/farmacología , Adhesión Bacteriana/efectos de los fármacos , Recuento de Colonia Microbiana , Escherichia coli/efectos de los fármacos , Escherichia coli/ultraestructura , Soluciones , Propiedades de Superficie , Agua
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