Inhibitory effect on NO production of phenolic compounds from Myristica fragrans.
ABSTRACT Three new phenolics: ((7S)-8'-(benzo[3',4']dioxol-1'-yl)-7-hydroxypropyl)benzene-2,4-diol (1), ((7S)-8'-(4'-hydroxy-3'-methoxyphenyl)-7-hydroxypropyl)benzene-2,4-diol (2) and ((8R,8'S)-7-(4-hydroxy-3-methoxyphenyl)-8'-methylbutan-8-yl)-3'-methoxybenzene-4',5'-diol (3), along with four known compounds (4-7) were isolated from the seeds of Myristica fragrans. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells.
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ABSTRACT: This study investigated the occurrence of fungi with the potential to produce ochratoxin A (OTA), and the occurrence of OTA, in Brazilian cocoa beans. Two hundred and twenty two samples of cocoa were evaluated, taken at various stages of fermentation, drying and storage. Samples were collected from Bahia, the main cocoa producing region in Brazil. Fungi with the potential to produce OTA were isolated by direct plating of cocoa beans on Dichloran 18% Glycerol agar after surface disinfection, and identified by standard techniques. The ability of the fungi to produce OTA was estimated using the agar plug technique and TLC. The presence of OTA in cocoa samples was determined by HPLC after immunoaffinity column clean up. The most common ochratoxigenic species found were Aspergillus carbonarius and A. niger aggregate, with lower numbers of A. melleus, A. westerdijkiae and Av. ochraceus. A considerable increase in the numbers of these species was observed during drying and storage. OTA was found at all stages of cocoa processing, with the major incidence during drying and storage. The OTA levels found were in general low and there was a strong positive correlation between the presence of A. carbonarius and OTA contamination in the beans.International journal of food microbiology 09/2010; 143(1-2):67-70. · 3.01 Impact Factor
Article: Mycotoxins in edible tree nuts.[show abstract] [hide abstract]
ABSTRACT: Tree nuts (almonds, pistachios, and walnuts) are an exceptionally valuable crop, especially in California, with an aggregate value approaching $3.5 billion. Much of this economic value comes from overseas markets, with up to 60% of the crop being exported. The product can be contaminated with aflatoxins or ochratoxins, with the former being of special concern because of the strict regulatory levels (4 ppb total aflatoxins) applied by the European Community (EC). Natural, consumer-acceptable control methods are therefore required to conform to such limits. Research has shown that aflatoxin production is markedly decreased by the presence of natural antioxidants that occur in tree nuts, including hydrolysable tannins, flavonoids and phenolic acids. In vitro testing of individual compounds showed that the antiaflatoxigenic effect correlated with the structure and concentration of such compounds in individual nut varieties and species. This lead to the hypothesis that aflatoxin biosynthesis is stimulated by oxidative stress on the fungus and that compounds capable of relieving oxidative stress should therefore suppress or eliminate aflatoxin biosynthesis. Oxidative stress induced in A. flavus by addition of tert-butyl hydroperoxide to the media stimulated peak aflatoxin production and maintained high levels over time. However, aflatoxin formation was significantly inhibited by incorporation into the media of the antioxidant, tannic acid. Measures to increase natural products with antioxidant properties in tree nuts may thereby reduce or eliminate the ability of A. flavus to biosynthesize aflatoxins, thus ensuring levels at or below regulatory limits and maintaining export markets for U.S. tree nuts.International Journal of Food Microbiology 11/2007; 119(1-2):72-8. · 3.43 Impact Factor
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ABSTRACT: Polyphenols have become an intense focus of research interest because of their perceived health-beneficial effects, such as anti-carcinogenic, anti-atherogenic, anti-inflammatory, anti-microbial, etc. Polyphenols in green and black tea, grape seeds, grapes and (red) wine have raised much attention but chocolate has not been investigated intensively up to now. This review is concerned with polyphenols in Theobroma cacao, the change in composition and quantity during fermentation, drying, and the manufacture of chocolate, as well as with analytical methods for isolation, characterisation and quantification. Cocoa beans are rich in polyphenols in particular catechins and proanthocyanidins. However, a sharp decrease in quantity occurs during fermentation and drying of cocoa beans and further retention has been reported during roasting. Characterisation and in particular quantification of polyphenols in chocolate has only been developed relatively recently. This work reviews further on the literature on the available methodology for analysis, quantification, isolation, purification, and structure elucidation of polyphenols in cocoa components and other commodities. Concerning the analytical methods main emphasis is put on HPLC as it is usually the method of choice due to its high resolution, high efficiency, high reproducibility and relatively short analysis time without restriction on sample volatility. Moreover, HPLC can be coupled to a variety of detectors such as UV–Vis, photodiode array (PDA), fluorescence, electrochemical (ECD), and mass spectrometry (MS). However, TLC as a screening method and capillary electrophoresis (CE) as a promising tool is taken into consideration as well. The characterisation and quantification of the polyphenol composition is amongst the first steps to be done to evaluate a putative contribution of chocolate to human health.Food Research International. 01/2000;