In Europe, bilberry (Vaccinium myrtillus Linne) fruits extracts are used as herbal drugs, while they are categorized as foods in Japan. In this study, we evaluated the quality of 7 bilberry products obtained in Japanese markets by using HPLC. Both anthocyanins and anthocyanidins, the latter of which are degradation products of anthocyanins during storage, were used as specific marker compounds. Among the products, the HPLC profiles are divided 3 groups. The fist one (samples A, C and F) showed the same profile as that of an on-specification product to European Pharmacopoeia (EP product). The second one (samples B, E and G) showed the profile not similar to that of the EP product. The last one (sample D) showed additional peaks such as cyanidin 3-O-rutinoside to the HPLC profile of EP products. These data suggest the origin of the second group might not be derived bilberry. In addition, the sample D may contain other additional plant extract(s). Then, we compared the ratio of anthocyanidins to anthocyanins among the products. The results showed that the ratio of sample C and F is remarkably higher than that of sample A and the EP product. These results indicate that there are significant differences in the quality of these products.

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tert-Butylhydroquinone (TBHQ) is a synthetic antioxidant, which is prohibited using as a food additive in Japan. Acetonitrile was one of the solvents used for the extraction of TBHQ from foods and for the HPLC analysis in the official method. In this study, the application of methanol as an alternative solvent was evaluated due to the shortage of acetonitrile through worldwide depression. Results showed that the revised method was well achieved according to the official method with some improvement. The mobile phase of HPLC was changed in 5% acetic acid-methanol (55:45). In addition, the linearity of calibration curve was obtained the peak areas versus the concentrations at the range of 0.1-5μg/mL. The recoveries of TBHQ spiked at the level of 20μg/g were 80.3-99.0%, and that of 2μg/g were 81.8-109.8% for olive oil, peanut butter, chewing gums, and potato chips.

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A simple and efficient method has been developed for determining of aspartame (L-APM), its epimer (D-APM), their degradation products, diketopiperazine (DKP) and DL-phenylalanine (Phe), utilizing high performance liquid chromatography (HPLC). These compounds were separated on a reverse-phase octadecyl silica gel column coated with N,S-dioctyl-D-penicillamine (SUMICHIRAL OA-5000, monolithic-type, 4.6mm×100mm), using 2mM CuSO₄-acetonitrile-isopropyl alcohol (85:10:5) as a mobile phase. The column temperature was set to 30℃ and a UV absorption detector was set at 254nm. The detection limits of L-APM, D-APM, DKP and DL-Phe were 10μg/mL, 1μg/mL, 10μg/mL and 0.1μg/mL, respectively. The concentrations of D-APM and DKP contained in L-APM are prescrived below 0.04% and 1.5% in the Japan's specifications and standards for food additive. The mixture of L-APM 2500μg/mL, D-APM 1μg/mL (0.04% for L-APM) and DKP 37.5μg/mL (1.5% for L-APM) was analyzed separately using this method.

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ヘッドスペースガスクロマトグラフィー(HS-GC法)は薬品、食品添加物および食品中の残留溶媒の分析法として頻繁に用いられている方法である。本研究では、増粘安定剤(カロブビーンガム、グアーガム、ジェランガム)中のメタノールおよび2-プロパノールを分析対象とし、標準添加法を用いたヘッドスペースガスクロマトグラフィー法(HS-GC法)および水で蒸留後、留液をガスクロマトグラフィーで分析する方法(蒸留-GC法)により分析し、両方法で得られる溶媒量の比較検討を行った。その結果、HS-GC法と蒸留-GC法ではほぼ同程度の溶媒量が検出された。以上の結果から、増粘安定剤のような粘性の高い試料に対して、標準添加法によるHS-GC法は蒸留-GC法などと同等有用な方法であると考えられた。また、いずれの分析法においてもキャピラリーカラム(Aquatic-2ジーエルサイエンス(株))を用いて良好な分離が得られた。

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The biodegradability of sucralose, a non-calorie high-intensity sweetener, in an activated sludge collected in Japan was investigated by analytical methods. HPLC revealed that sucralose was biodegraded via dechlorination in the Japanese activated sludge. 1,6-Dichlorofructose (1,6-DCF) and 6-chlorofructose (6-CF) were identified as degradation intermediates of sucralose by LC/MS and LC/MS/MS. It was found by HPLC that they were also biodegraded via dechlorination in the Japanese activated sludge. These results suggest that sucralose and its degradation intermediates, 1,6-DCF and 6-CF, are biodegradable in a natural environment in Japan. Aerobic enrichment culture of a mixture of sucralose and the activated sludge was made to identify sucralose-degrading bacteria. Bacteria belonging to the Bacteroides-Flavobacterium family as well as Sphingomonas (Sphingopyxis) and Xanthomonas genera were predominantly detected in the culture solution by 16S rDNA analysis and quinone profiling. These results suggest that these bacteria are involved in the biodegradation of sucralose.

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Ozokerite, a natural gum base used as a food additive, is described as a purified wax substance found in veins of wax shale and is composed mainly of C₂₉-C₅₃ hydrocarbons, in the Notice (1996) relating to existing food additives in Japan. In order to evaluate the quality of commercially available ozokerite, we have analyzed the constituents. GC/MS analysis of ozokerite showed that the main components were saturated C₂₂-C₃₈ hydrocarbons, while the minor components were saturated C₃₉-C₅₈ hydrocarbons. The range of carbon numbers observed in the main saturated hydrocarbons was lower than those referred to in the Notice. The total concentration of the main saturated C₂₂-C₃₈ hydrocarbons was found, by GC/FID analysis, to be 81%.

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