Application of Nitrate Reductase for the Determination of Nitrate in Meat and Fishery Products |
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| Authors: | Takashi Hamano Yukimasa Mitsuhashi Kisaku Tanaka Yukio Matsuki Yoshikiyo Oji Saburo Okamoto |
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| Institution: | 1. Public Health Research Institute of Kobe City, Chuo-ku, Kobe 650, Japan;2. Department of Agricultural Chemistry, Faculty of Agriculture, Kobe University, Nada-ku, Kobe 675, Japan |
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| Abstract: | A rapid and specific method is described for the determination of nitrate in meat and fishery products.Nitrate separated from foods by extraction with 1/50Ν sodium hydroxide and ultrafiltration was readily reduced to nitrite by the use of respiratory nitrate reductase (NR) from Escherichia coli K-12. The nitrite so obtained can be determined by the specific diazotation-coupling reaction method.The use of an enzymatic reaction resulted in quantitative reduction of nitrate, and the method was relatively free of interferences. Recoveries of 10 and 100 ppm of nitrate from 5 samples of meat and fishery products ranged from 92.8 to 97.8% for 10 ppm and 97.8 to 99.4% for 100 ppm with a detection limit of 0.5 ppm. |
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| Keywords: | calcium-dependent protein kinase in silico cloning heat stress phytohormone tomato |
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