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Volume 54 (2013)
- Issue 6 Pages 385-
- Issue 5 Pages 351-
- Issue 4 Pages 251-
- Issue 3 Pages 173-
- Issue 2 Pages 83-
- Issue 1 Pages 1-
Volume 54, Issue 5
Displaying 1-6 of 6 articles from this issue
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Original Papers
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Motoki OGISO, Takashi MORITA, Chisato HARADA, Satoshi ISAGAWA, Hiroshi ...Article type: Original Paper
2013 Volume 54 Issue 5 Pages 351-357
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSWe examined whether immunochemical-based test kits designed for quantitative analysis of deoxynivalenol (DON) screening in grain crops are applicable to corn processing by-products. Commercially available test kits (two types of immunochromatographic kits and three types of ELISA kits) were used to assay three types of corn processing by-products and mixed feed. The results obtained with some kits were significantly different from those of LC-MS analysis. Since the differences might be caused by insufficient extraction of DON from samples, the extraction time of all kits was set to be 20 minutes, based on a study of the dependence of the amount of DON extracted on the shaking time. Moreover, the extract of corn processing by-products was acidic, resulting in inhibition of the antigen-antibody reaction, so neutralization and centrifugation processes were introduced to prevent denaturation of antibody. After these modifications, the recovery for all kits in assays of corn gluten meal was within the range of 80–120%, and all kits showed acceptable accuracy. The relative standard deviation (RSD) of repeatability tests for all kits was less than 11.3% for analyses of both corn processing by-products and mixed feeds, indicating good precision. The above results showed that the kits studied were applicable to the quantitative assay of DON in corn processing by-products and mixed feed after modifications as described in this paper.View full abstractDownload PDF (163K) -
Tetsuya SHINDO, Yuki SADAMASU, Keiko SUZUKI, Yasukazu TANAKA, Akiko TO ...Article type: Original Paper
2013 Volume 54 Issue 5 Pages 358-363
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSA reliable quantitative determination method of sugar alcohols, D-mannitol, xylitol and D-sorbitol, in food samples by HPLC, and a simple confirmation method by LC-MS were developed. Quantitative HPLC analysis was performed using a separation column packed with polystyrene cation exchange resin of sulfonic acid type, and with pure distilled water as the mobile phase. This column, operated at 0.85 mL/min flow rate of mobile phase and 50℃ column oven temperature, completely separated the three sugar alcohols. Further, these three sugar alcohols were well separated from erythritol and other sugars (sucrose, D-glucose, D-xylose and D-fructose). Recoveries of the three sugar alcohols spiked into food samples, such as orange juice, yogurt, chewing gum and milk, exceeded 91% and the values of coefficient of variance were below 3.1%. A triple extraction process with 80% ethanol was needed for biscuit to achieve recoveries exceeding 82%. LC-MS was carried out on a NH2 column with acetonitrile–water (9 : 1) as the mobile phase, and this afforded partial but acceptable separation of the three sugar alcohols with in 10 minutes. Ion peaks derived from [M-H]- and [M+Cl]- were clearly detected for all three sugar alcohols in the negative electrospray inization mode at 30 V cone voltage. The positive electrospray ionization mode produced the ions [M+Na]+ and [M+Na+CH3CN]+. These characteristic ions served to confirm the presence of the sugar alcohols in food samples.View full abstractDownload PDF (700K) -
Yoshimasa KASAHARA, Takeshi ITOU, Toshiaki NUMAZAWA, Akinobu WADAArticle type: Original Paper
2013 Volume 54 Issue 5 Pages 364-369
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSSimultaneous determination of four aconitine analogues (ACs) (AC; aconitine, HA; hypaconitine, JA; jesaconitine, MA; mesaconitine) in leaves and roots of wild Aconitum plants (Aconitum japonicum THUNBERG, Aconitum okuyamae Nakai) was carried out to elucidate the relation between toxicity to mice and ACs content determind by liquid chromatography tandem mass spectrometry. The total amounts of ACs in leaves, roots, petals and nectaries of Aconitum japonicum collected at Sagae-shi Tashiro were 5.9 μg/g, 928.1 μg/g, 46.1 μg/g, and 69.8 μg/g, respectively. Despite the high contents in nectary, commercial honey contained no ACs. Extract of wild Aconitum japonicum roots which contained ACs (2.69 mg/g) was administered to 5 mice orally at 1.0 g/kg (fresh root equivalent), and 2 mice died. On the other hand, 3 of 5 mice died after being given the standard AC (3.0 mg/kg, p.o.). These findings confirmed good coincidence between toxicity and quantitative values. Mice given extract of Aconitum okuyamae root (100 g/kg, p.o.) without ACs showed no toxic symptoms. Residual ACs in Aconitum leaves were examined after boiling. The remaining percentage of ACs in leaves after 0.5 minutes boiling was 31.6%, and the amount in the boiling water was 54.5%. MA is converted into benzoylmesaconine by hydrolysis (by boiling). Therefore food poisoning caused by Aconitum plants is explained by detection of benzoylmesaconine formed during food preparation.View full abstractDownload PDF (474K) -
Mayumi HASEGAWA, Kaoru YAMAZAKI, Osamu BABAArticle type: Original Paper
2013 Volume 54 Issue 5 Pages 370-373
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSWe observed the effect of starfish (Asterias amurensis) intake during 67 days, on rats, in terms of the activity of enzymes related to liver function and biochemical values related to weight gain, lipid metabolism and safety. 1. Starfish (Asterias amurensis) did not induce a significant difference of body weight change. 2. Starfish (Asterias amurensis) intake did not affect organ weight. 3. Starfish (Asterias amurensis) intake did not affect lipid metabolism, liver function, or protein nutrition in this experiment.View full abstractDownload PDF (339K)
Notes
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Daisuke MIYAKE, Kenji HAYAKAWA, Takakazu NOMURAArticle type: Note
2013 Volume 54 Issue 5 Pages 374-378
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSA quantitative analytical method for 8 volatile substances (such as styrene) in styrene polymers that are not soluble in tetrahydrofuran (THF) and dimethylformamide was developed. The sample was chopped finely and a 0.1 g portion was weighed in a head-space vial. To this was added 2 mL of o-dichlorobenzene (DCB) including 50 μg/mL of internal standard. The vial was sealed and heated at 140℃ for 1 hour and then 1 mL of the head-space gas was injected into a gas chromatograph using an automatic sampler. Samples of syndiotactic polystyrene, styrene block copolymer and modified polyphenylenether were dissolved or dispersed in DCB. Separation and accuracy of the method were satisfactory. Recoveries were 95–113% at the spiked concentration of 300 μg/g. The method was confirmed to be suitable for general styrene polymers that are soluble in THF. Equivalent results were obtained with this method and the method in “Specifications and Standards for Food, Food Additives, etc. ” for general purpose polystyrene, high impact polystyrene, styrene/acrylonitrile resin and acrylonitrile/butadiene/styrene resin.View full abstractDownload PDF (333K) -
Takashi HASEGAWA, Kazunaga TAKAHASHI, Tomohide FUKIWAKE, Masaaki SAIJO ...Article type: Note
2013 Volume 54 Issue 5 Pages 379-383
Published: October 25, 2013
Released on J-STAGE: November 02, 2013
JOURNAL FREE ACCESSWe developed a simple and rapid liquid chromatography/mass spectrometry (LC/MS) method for the enantiomeric determination of DOPA in dietary supplements containing Mucuna pruriens. L- and D-DOPA were ultrasonically extracted with 1% formic acid aqueous solution. The isolated extracts were analyzed by LC/MS using a Crownpak CR (-) column at 30℃. The mass spectrometer was operated in the positive mode of electrospray ionization, and the mobile phase was aqueous formic acid (pH 2.0). L-DOPA-ring-d3 was used as an internal standard. The method was validated for a dietary supplement spiked with L- and D-DOPA at 50 and 500 μg/g, respectively, and the recoveries of the DOPA enantiomers were between 97.5% and 101.3%. Relative standard deviation values of repeatability and intermediate precision were less than 7%. The method was applied to 14 dietary supplements. L-DOPA was detected in these supplements in the range of 0.88–12.8 mg/unit. D-DOPA was not detected.View full abstractDownload PDF (270K)
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