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1.
J Agric Food Chem ; 48(2): 520-3, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10691669

RESUMO

This article gives a description of the setup in a laboratory of a pilot system to reduce phosphine following the smoking process of foodstuffs. At present, this fumigant is released into the atmosphere and causes serious damage to the environment due to its transformation into aggressive compounds. However, phosphine may prove a good alternative to methyl bromide, which will legally be used as a fumigant until the year 2002, provided it is made inert after the smoking process and transformed into nontoxic and easily disposable substances. Oxidant solutions containing potassium permanganate or potassium bichromate in suitable concentrations proved moderately effective in reducing phosphine. The addition of traces of silver nitrate as a catalyst to the oxidant solutions increased the efficiency in reducing the fumigant, although not completely. Thus it was necessary to use a recycling system to decontaminate air from phosphine, as such an apparatus ensures the complete reduction of phosphine. The mathematical function describing how the concentration of phosphine varies in the smoking chamber also makes it possible to estimate the time necessary to reduce a phosphine concentration from any initial value to a fixed final value.


Assuntos
Manipulação de Alimentos/métodos , Fosfinas/metabolismo , Fumaça , Cromatografia Gasosa-Espectrometria de Massas , Compostos de Manganês , Oxirredução , Óxidos , Dicromato de Potássio , Nitrato de Prata
2.
J Agric Food Chem ; 47(1): 202-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10563872

RESUMO

A simpler and faster procedure than the official one described in document IV of European Economic Community Regulation 183/93 is proposed. The wax ester fraction is isolated from triglycerides using a commercially available silica gel column and carbon tetrachloride as eluent. The recovered wax ester fraction, with the addition of a suitable internal standard solution, is analyzed by gas chromatography. A column with a 65% phenyl methyl silicone stationary phase allows a satisfying separation of wax ester fraction in comparison with both a steryl ester and a light fraction eluted before the internal standard. Furthermore, also the single components of the wax ester fraction are suitably separated.


Assuntos
Óleos de Plantas/química , Cromatografia Gasosa , Ésteres , Azeite de Oliva
4.
Biochim Biophys Acta ; 573(1): 51-60, 1979 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-454639

RESUMO

A homogeneous cerebroside was isolated from a strain of Fusicoccum amygdali Del., a fungus pathogenic to almond and peach. Chemical degradations, together with extensive application of nuclear magnetic resonance and mass spectrometry techniques, led to elucidation of its structure. This corresponds to N-2'-hydroxy-3'-trans-octadecenoyl-1-O-beta-D-glucosyl-9-methyl-cis-4,x-8-sphingadienine.


Assuntos
Cerebrosídeos/isolamento & purificação , Fungos Mitospóricos/análise , Cromatografia/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
8.
J Chromatogr ; 38(2): 282-6, 1968 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-5705288
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