Aflatoxins can cause damage to the health of humans and animals. Several institutions around the world have established regulations to limit the levels of aflatoxins in food, and numerous analytical methods have been extensively developed for aflatoxin determination. This review covers the currently used analytical methods for the determination of aflatoxins in different food matrices, which includes sampling and sample preparation, sample pretreatment methods including extraction methods and purification methods of aflatoxin extracts, separation and determination methods. Validation for analysis of aflatoxins and safety considerations and precautions when doing the experiments are also discussed.
Yang Y, Chen M, Georgeson KE, Harmon CM. Mechanism of oleoylethanolamide on fatty acid uptake in small intestine after food intake and body weight reduction. The increase in the prevalence of human obesity highlights the need to identify molecular and cellular mechanisms involved in control of feeding and energy balance. Oleoylethanolamide (OEA), an endogenous lipid produced primarily in the small intestine, has been identified to play an important role in the regulation of animal food intake and body weight. Previous studies indicated that OEA activates peroxisome proliferator-activated receptor-␣, which is required to mediate the effects of appetite suppression, reduces blood lipid levels, and enhances peripheral fatty acid catabolism. However, the effect of OEA on enterocyte function is unclear. In this study, we have examined the effect of OEA on intestinal fatty acid uptake and FAT/CD36 expression in vivo and in vitro. We intraperitoneally administered OEA to rats and examined FAT/CD36 mRNA level and fatty acid uptake in enterocytes isolated from the proximal small intestine, as well as in adipocytes. Our results indicate that OEA treatment significantly increased FAT/CD36 mRNA expression in intestinal mucosa and isolated jejunal enterocytes. In addition, we also found that OEA treatment significantly increases fatty acid uptake in isolated enterocytes in vitro. These results suggest that in addition to appetite regulation, OEA may regulate body weight by altered peripheral lipid metabolism, including increased lipolysis in adipocytes and enhanced fatty acid uptake in enterocytes, both in conjunction with increased expression of FAT/CD36. This study may have important implications in understanding the mechanism of OEA in the regulation of fatty acid absorption in human physiological and pathophysiological conditions. obesity; enterocyte; fatty acid translocase/CD36 OBESITY HAS BECOME one of the most significant public health problems facing the world today (4,11,20,25,30). In the United States the prevalence of obesity has risen by 32% in adults and 40% in children over last two decades . A better understanding of how energy balance is maintained is critical to developing effective therapeutic strategies for obesity. Oleoylethanolamide (OEA) is a naturally occurring lipid mediator that inhibits food intake and body weight gain and therefore has been a molecule of recent intense scientific interest in the search for therapeutic strategies for the treatment of human obesity (13, 24).OEA is synthesized in brain, adipocytes, and the small intestine and is structurally similar to the endogenous cannabinoid anandamide (arachidonoylethanolamide), but it does not bind to or activate cannabinoid receptors. Rather, pharmacological and molecular biological experiments have demonstrated that OEA induces satiety (14) and reduces body weight gain in mice and rats (24) through activation of the nuclear receptor peroxisome proliferator-activated receptor (PPAR)-␣ (13). This ligand-activated transcription factor is abundantl...
Ganoderic acid A from Ganoderma lucidum has the potential to prevent hyperlipidemia, modulates the composition of gut microbiota in hyperlipidemic mice, and significantly attenuates the liver metabolite profile in hyperlipidemic mice.
A highly efficient transformation system mediated by polyethylene glycol was developed for the cultivated mushroom Pleurotus ostreatus. Eighty to 180 integrative and stable-resistant colonies appeared per mug of DNA per 10(7) viable protoplasts in a transformation experiment with the hygromycin B phosphotransferase gene (hph), which is about 40-1800 times higher than that previously reported in P. ostreatus. One hundred to 150 transformants emitting green fluorescence were observed per mug of DNA per 10(7) viable protoplasts in a transformation with the green fluorescent protein gene, but green fluorescence disappeared 30 h after transformation, suggesting that the green fluorescent protein gene was only transiently expressed in P. ostreatus. Plasmid pAN7-1 was also transferred into two important cultivated mushrooms, Ganoderma lucidum and Lentinus edodes, and 120-150 and 85-100 transformants per mug of DNA per 10(7) viable protoplasts were obtained, respectively, which is seven to 38 times and 24-28 times greater than previously reported. These data indicate that this new polyethylene glycol-mediated transformation procedure is highly efficient for mushrooms, and could be a useful tool in mushroom improvement by gene engineering.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.