落花生之黄曲毒素防治与其保健植物化合物之探讨

Elimination of Aflatoxin Contamination and Characterization of Health Enhancing Phytochemicals of Peanuts

落花生是全球熟悉与普遍消费的作物,其特殊之香气与酥脆质地吸引绝大多数消费者的味口。然而,由于落花生可能被黄曲毒素产生菌污染产毒,导致许多消费者常将落花生与黄曲毒素(系一种天然致癌物质)联想在一起,因而犹豫甚至拒绝进食含落花生之产品。落花生虽然是黄曲毒素产生菌生长之良好基质,但必须遭受其侵入,且得到充分生长才会产毒。田间栽种时有适当灌溉、采收后花生荚果迅速干燥,以及良好仓储条件,是落花生采收前后有效降低黄曲毒素污染的最重要方法。加工时,先将花生仁轻度焙烤,再脱膜并以色差电子自动筛检,则能更进一步将被霉菌污染之花生仁筛除,筛选后之花生仁可加工制作安全无虞之高品质食品。另外,有鉴于黄曲毒素产生菌普遍存在于土壤中,但采收后之健康花生荚或花生仁几乎均无黄曲毒素之污染,经探讨得知,落花生具有生合成二苯乙烯类化合物(包括熟知的白藜芦醇在内之植物防御素)以抵抗微生物入侵之本能。因此,落花生可经由发芽制备花生芽作为机能蔬菜,并促进生合成二苯乙烯类化合物,包括白藜芦醇,Arachidin-1,Arachidin-3及Isopentadienylresveratrol(IPD)等,这些二苯乙烯类化合物目前已知,具有相当值得重视的抗氧化与抗发炎活性,具有进一步开发作为饮食补充或保健产品之潜力。

Peanut （Arachis hypogaea L.） is a worldwide familiar and consumed crop.Its unique and pleasant peanutty aroma and crispy texture have attracted good appetite of most consumers.However,the fact that peanut may be contaminated with aflatoxin,a potent carcinogen,makes some consumers hesitate to eat peanut-containing foods.Aflatoxin is produced only when peanut pods or kernels have been sufficiently grown by the aflatoxin producing molds.Field irrigation during cultivation and good practices of harvesting,drying and warehouse storage are essential in decreasing pre-harvest and post-harvest aflatoxin contamination.From the viewpoint of peanut processing,electronic color sorting of the lightly roasted and deskinned peanut kernels was effective in diminishing aflatoxin contamination of the peanut kernels.Even aflatoxin producing molds are present widely in the peanut growing soils,most of the healthy peanut kernels after harvesting are free of aflatoxin contamination.Intrinsically,peanut is capable of biosynthesis of stilbenoids,called phytoalexins,including the well-known resveratrol,against microbial infection.Biosynthesis of resveratrol and other stilbenoids including arachidin-1,arachidin-3 and isopentadienylresveratrol （IPD） could be enhanced by germination in preparation of peanut sprouts as a functional vegetable.Those stilbenoids have been demonstrated as potent antixodants and inflammatory inhibitors which deserve further research interests in development of nutraceutical and health-benefit products.