著者
Kiyoko Kaneko Yasuo Aoyagi Tomoko Fukuuchi Katsunori Inazawa Noriko Yamaoka
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.37, no.5, pp.709-721, 2014-05-01 (Released:2014-05-01)
参考文献数
42
被引用文献数
103 155

Purines are natural substances found in all of the body’s cells and in virtually all foods. In humans, purines are metabolized to uric acid, which serves as an antioxidant and helps to prevent damage caused by active oxygen species. A continuous supply of uric acid is important for protecting human blood vessels. However, frequent and high intake of purine-rich foods reportedly enhances serum uric acid levels, which results in gout and could be a risk factor for cardiovascular disease, kidney disease, and metabolic syndrome. In Japan, the daily intake of dietary purines is recommended to be less than 400 mg to prevent gout and hyperuricemia. We have established an HPLC method for purine analysis and determined purines in a total of 270 foodstuffs. A relatively small number of foods contained concentrated amounts of purines. For the most part, purine-rich foods are also energy-rich foods, and include animal meats, fish meats, organs such as the liver and fish milt, and yeast. When the ratio of the four purine bases (adenine, guanine, hypoxanthine, and xanthine) was compared, two groups of foods were identified: one that contained mainly adenine and guanine and one that contained mainly hypoxanthine. For patients with gout and hyperuricemia, the amount of total purines and the types of purines consumed, particularly hypoxanthine, are important considerations. In this context, the data from our analysis provide a purine content reference, and thereby clinicians and patients could utilize that reference in nutritional therapy for gout and hyperuricemia.
著者
Tomoko FUKUUCHI Makoto YASUDA Katsunori INAZAWA Tatsuhiro OTA Noriko YAMAOKA Ken-ichi MAWATARI Kazuya NAKAGOMI Kiyoko KANEKO
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.29, no.5, pp.511-517, 2013-05-10 (Released:2013-05-10)
参考文献数
31
被引用文献数
6 25

Several methods for quantifying the purine content in food and drink have been described using high-performance liquid chromatography (HPLC). We have developed an improved HPLC method that is based on a method reported by Kaneko et al. and that is more sensitive yet simple, and suitable for determining the purine content of beer and beer-like alcoholic beverages. Quantitative HPLC separation was performed on a Shodex Asahi Pak GS-320HQ column with an isocratic elution of 150 mmol/L sodium phosphate buffer (H3PO4/NaH2PO4 = 20:100 (v/v)). The retention times for the four analytes, namely, adenine, guanine, hypoxanthine and xanthine, were 19.9, 25.0, 29.3 and 43.0 min, respectively. The resolution was good, and there was no excessive interference from the other compounds in the beverages at these retention times. Furthermore, the detection limit for all the analytes was improved to less than 0.0075 mg/L, and all the calibration curves showed good linearity (r2 > 0.999) between 0.013 and 10 mg/L for adenine and guanine, and between 0.025 and 10 mg/L for hypoxanthine and xanthine. The pretreatment was simplified by removing some procedures and optimizing the perchloric acid hydrolysis and the enzymatic peak-shift assay. We reduced the sample dilution rate by almost 50%, and the time spent on pretreatment from 4 days to only 180 min. The recovery of the analytes from spiked samples was 94.8 – 103.8%. This method may be useful for evaluating quantitative and qualitative differences in the purine content of beer and beer-like alcoholic beverages.