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1.
J Food Sci ; 84(8): 2121-2127, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31269247

RESUMO

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.


Assuntos
Ácidos Graxos/química , Hibiscus/química , Óleos Vegetais/química , Armazenamento de Alimentos , Temperatura Alta , Ácido Linoleico/análise , Oxirredução , Sementes/química , Tocoferóis/análise , Tocotrienóis/análise , Triglicerídeos/análise , Vitamina E/análise
2.
Appl Radiat Isot ; 139: 224-230, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29852404

RESUMO

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.


Assuntos
Aflatoxina B1/análise , Aflatoxina B1/efeitos da radiação , Irradiação de Alimentos/métodos , Óleo de Soja/química , Óleo de Soja/efeitos da radiação , Soja/química , Soja/efeitos da radiação , Ácidos Graxos/análise , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Fungos/isolamento & purificação , Fungos/efeitos da radiação , Raios gama/uso terapêutico , Humanos , Oxirredução , Tocoferóis/análise
3.
J Oleo Sci ; 67(3): 255-263, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29459511

RESUMO

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.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Eucommiaceae/química , Qualidade dos Alimentos , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Sementes/química , Dióxido de Carbono , Fenômenos Químicos , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/análise , Pressão , Temperatura Ambiente , Fatores de Tempo , Vitamina E/análise , Ácido alfa-Linoleico/análise
4.
J Food Sci ; 83(3): 617-623, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29355957

RESUMO

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.


Assuntos
Eucommiaceae/química , Óleos Vegetais/química , Ácido alfa-Linoleico/química , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/química , Ácido Linoleico/análise , Ácido Oleico/análise , Sementes/química , Tocoferóis/análise , Triglicerídeos/análise , Vitamina E/análise , gama-Tocoferol/análise
5.
Pest Manag Sci ; 71(3): 404-14, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24777582

RESUMO

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.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/química , Fungicidas Industriais/síntese química , Ácidos Graxos Insaturados/síntese química , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Fungicidas Industriais/farmacologia , Espectroscopia de Ressonância Magnética , Metacrilatos/síntese química , Metacrilatos/química , Metacrilatos/farmacologia , Oximas/síntese química , Oximas/química , Oximas/farmacologia , Relação Estrutura-Atividade
6.
Chem Biol Drug Des ; 85(6): 743-55, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25346294

RESUMO

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.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/química , Indóis/química , Oximas/química , Éteres/síntese química , Éteres/química , Éteres/farmacologia , Ácidos Graxos Insaturados/síntese química , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Indóis/síntese química , Indóis/farmacologia , Metacrilatos/síntese química , Metacrilatos/química , Metacrilatos/farmacologia , Oximas/síntese química , Oximas/farmacologia , Estrobilurinas , Relação Estrutura-Atividade
7.
Bioorg Med Chem Lett ; 24(9): 2173-6, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24717155

RESUMO

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.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Tiofenos/química , Tiofenos/toxicidade , Ácidos Graxos Insaturados/síntese química , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/toxicidade , Fungicidas Industriais/síntese química , Metacrilatos/síntese química , Metacrilatos/química , Metacrilatos/toxicidade , Oximas/síntese química , Oximas/química , Oximas/toxicidade , Estrobilurinas , Tiofenos/síntese química
8.
Colloids Surf B Biointerfaces ; 111: 252-6, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23831592

RESUMO

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.


Assuntos
Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/fisiologia , Polímeros de Fluorcarboneto/farmacologia , Aço Inoxidável/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Contagem de Colônia Microbiana , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Soluções , Propriedades de Superfície , Água
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