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Volume 43 (2002)
- Issue 6 Pages 323-
- Issue 5 Pages 267-
- Issue 4 Pages 191-
- Issue 3 Pages 115-
- Issue 2 Pages 57-
- Issue 1 Pages 1-
Volume 43, Issue 4
Displaying 1-14 of 14 articles from this issue
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Originals
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Yoko KAWASAKI, Naoki SUGIMOTO, Kyoko SATO, Takeshi YAMAZAKI, Hajimu IS ...2002 Volume 43 Issue 4 Pages 191-195
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSAn unknown red pigment was purified from an apple syrup product imported from Canada, using a DIAION HP-20 column with methanol as the eluent. By spectroscopic means and chemical synthesis, the isolated pigment was identified as 4-aminocarminic acid, which is the major pigment of acid-stable carmine (a red colorant illegal in Japan). In addition, HPLC and TLC methods were proposed to detect this illegal colorant. While the color of carminic acid changed from yellow to red in the pH range of McIlvaine buffer (3.0∼7.0), the color of 4-aminocarminic acid was always red, and also the ultraviolet/visible (UV/Vis) spectra did not change. These characteristics are useful to distinguish 4-aminocarminic acid from carminic acid.View full abstractDownload PDF (484K) -
Nobuyuki YAMADA, Jutaro TAKAHATA, Kumiko SASAKI, Masatake TOYODA, Ryuj ...2002 Volume 43 Issue 4 Pages 196-201
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSWe studied a gas chromatographic method for the determination of dichlorvos (DDVP) and trichlorfon (DEP) in agricultural products. DDVP and DEP were extracted from agricultural products with acetone and re-extracted with ethyl acetate instead of dichloromethane. DDVP and DEP were eluted in one fraction on a silica gel column using n-hexane-acetone (1 : 1). DEP is a thermally labile compound, so it was derived to a more thermally stable compound by acylation with N-methylbis(trifluoroacetamide) and pyridine in acetone at 60°C for 2 hours. DDVP and the DEP-TFA derivative were determined simultaneously by GC-FPD. The recoveries of DDVP and DEP from agricultural products spiked at levels of 0.1 μg/g were 72.6∼117.7% and 86.2∼106.6%, respectively. The detection limits were 0.03 μg/g in powdered tea and ≤0.01 μg/g in other samples.
An interlaboratory study by 6 laboratories was conducted to validate this proposed method for 6 crops. Repeatability ranged from 3.1 to 7.8% for DDVP and from 3.4 to 8.3% for DEP, and reproducibility, from 6.9 to 15.5% for DDVP, and from 7.9 to 21.8% for DEP. Precision values were well within statistically predicted levels.View full abstractDownload PDF (566K) -
Shuzo TAGUCHI, Seisaku YOSHIDA, Yukio TANAKA, Shinjiro HORI2002 Volume 43 Issue 4 Pages 202-207
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSA rapid and clean method for the analysis of aflatoxins (AFs) was developed by using a new column and post-column photochemical derivatization HPLC with fluorescence detection. The new cleanup column consisted of magnesia and basic alumina poured on the top of a commercial multi-functional mini-column. It was extremely effective for the cleanup of AFs from raw peanut, corn, buckwheat and red pepper. Fluorescent substances, which interfered with the analysis of AFs from corn, were completely absorbed at the top of the magnesia layer. Recoveries of AFs (B1, B2, G1, G2) added to raw peanuts, corn, buckwheat and red pepper were over 80% at two levels of fortification (higher level: 10, 3, 10, 3 ng/g, respectively, lower level: 1.0, 0.3, 1.0, 0.3 ng/g, respectively). Coefficients of variation were smaller than 12%, except the lower fortified level for red pepper. Limits of detection for AFs in raw peanuts, corn and buckwheat were 0.3 ng/g for B1 and G1, and 0.1 ng/g for B2 and G2. Those in red pepper were 0.5 ng/g for B1, B2, G1 and G2.View full abstractDownload PDF (620K) -
Hiroyuki OHNO, Masako SUZUKI, Shigehito NAKASHIMA, Taiki AOYAMA, Kazun ...2002 Volume 43 Issue 4 Pages 208-214
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSA simultaneous determination method for 9 organotin compounds in polyvinyl chloride (PVC) and silicone products used as kitchen utensils and food packages was developed using ethyl derivatization with sodium tetraethylborate (NaBEt4). Organotin compounds were extracted with acetone-hexane (3 : 7) from the samples after acidification and the extract was filtered and concentrated at under 40°C. After centrifugal separation, these compounds were derivatized with 2% NaBEt4 solution and determined by GC/MS. This method was applicable for simple routine analysis. Recoveries of spiked compounds were 49.1∼118.1% for 3 PVC products and 88.8∼102.2% for a siliconized paper. Monooctyltin, dioctyltin and trioctyltin compounds were found in all PVC food containers at the levels of 123∼1,380 μg/g, 1,770∼13,200 μg/g and 6.6∼139 μg/g, respectively. They also were found in 3 gloves, 5 spouts, 1 hose and 5 pipes. Some PVC products contained monomethyltin, dimethyltin, trimethyltin, monobutyltin and dibutyltin compounds at the levels of 97.3∼433 μg/g, 96.5∼5,120 μg/g, 8.5∼24.9 μg/g, 1.2∼852 μg/g and 1.2∼29.4 μg/g, respectively.View full abstractDownload PDF (672K) -
Yoko KAWAMURA, Motoh MUTSUGA, Chiseko WAKUI, Tamio MAITANI2002 Volume 43 Issue 4 Pages 215-220
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSThe use of polyvinyl chloride gloves containing di(2-ethylhexyl) phthalate for food contact applications is restricted. In their place, polyvinyl chloride gloves containing non-phthalate plasticizers (PVC-NP) have been introduced. They contained unknown substances, so they were studied by GC/MS, HR-MS and NMR. The chemical structures of the unknown substances were confirmed to be diethylene glycol dibenzoate, triethylene glycol dibenzoate, dipropylene glycol dibenzoate, and alkylsulfonic acid phenyl ester, which are plasticizers. Including di-isononyl adipate, the contents of the plasticizers were 37.5∼48.9% in the PVC-NP gloves, and their migration levels were 1,010∼1,390 ppm into n-heptane. These are very high levels. These plasticizers are not widely used for food contact polyvinyl chloride throughout the world, and they have also not been registered as self-standards by Japanese manufacturers. Careful consideration will be necessary for the selection of a suitable plasticizer substitute.View full abstractDownload PDF (578K) -
Yoko KAWASAKI, Hiroki KUBOTA, Chikako YOMOTA, Tamio MAITANI2002 Volume 43 Issue 4 Pages 221-224
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSAn effective clean-up procedure was developed to determine trace levels of bromate in bread by high-performance liquid chromatography with post-column flow reactor detection.
Bromate was extracted from bread with deionized pure water. After centrifugation, the supernatant was filtered through a paper filter. The filtrate was filtered through a 0.2 μm nylon filter and choride ion was removed by an IC-SP M Ag cartridge column or On-Guard Ag cartridge column.
The eluate was applied to an Oasis MAX anion exchange cartridge column. The column was washed with 20% acetic acid and water. Bromate was then eluted with 0.5% sodium nitrate solution. The eluate was determined by HPLC with post column flow reactor detection.
The method had a quantitation limit of 2 ng/g in bread products. Recoveries of bromate from bread ranged from 68 to 72% at a spiked bromate level of 2∼10 ng/g.View full abstractDownload PDF (387K)
Notes
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Taeko KOSAKA, Hirohiko HAMADA2002 Volume 43 Issue 4 Pages 225-229
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSA method was developed for analysis of thyroid hormones, 3,5,3'-triiodo-L-thyronine (T3) and L-thyroxine (T4), in health foods by liquid chromatography-electrospray ionization-mass spectrometry (LC/ESI-MS). In order to release T3 and T4 from thyroglobulin, samples were first hydrolyzed enzymatically using protease at a temperature of 37±1°C for 28 h. The T3 and T4 were extracted with ethyl acetate and then the ethyl acetate layer was evaporated. The residue was dissolved in the mobile phase and analyzed by LC/MS. The LC separation was carried out on a ODS-3 column (2.1×150 mm) using H2O/CH3CN/CH3COOH (650/350/5) as the mobile phase. LC/ESI-MS was performed in the selected ion monitoring (SIM) mode using [M+H]+ ions at m/z 652 for T3 and m/z 778 for T4. The detection limit of both T3 and T4 released from thyroglobulin was 0.1 μg/g in health foods. The present method was applied to analysis of three health foods which were labeled as foods for dieting. T3 and T4 were detected in two of the samples, and their contents were 16 and 29 μg/g and 31 and 90 μg/g, respectively.View full abstractDownload PDF (535K) -
Kazuhiko NISHIMURA, Toshiyuki SUZUKI, Yutaka ITABASHI2002 Volume 43 Issue 4 Pages 230-233
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSA highly sensitive HPLC with fluorescence detection was developed for the determination of free fatty acids (FFAs) in milk and dairy products. For this purpose, the FFAs were extracted from small amounts of milk (1.0 mL), cheese (0.5 g) and butter (0.5 g) using Sep-Pak cartridge columns, and then derivatized to 9-anthrylmethyl esters with 9-anthryldiazomethane (ADAM). Good separations of the ADAM derivatives of 16 FFAs (C4-C18) that exist in milk, cheese and butter, which permitted quantitative estimation of their individual FFAs, were achieved by HPLC on a C18 column (Cadenza CD-C18, 150×3 mm i.d.) using gradient elution with methanol and water. The acid values calculated from the contents of individual FFAs were in good agreement with those obtained by the conventional titration method. These results demonstrate that the present HPLC method is simple, sensitive and precise, and could be utilized widely for determination of the FFAs in milk and dairy products.View full abstractDownload PDF (400K) -
Masakazu HORIE, Rie ISHII, Susumu KOBAYASHI, Hiroyuki NAKAZAWA2002 Volume 43 Issue 4 Pages 234-238
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSA simple and reliable method using liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) for the analysis of tetrodotoxin in puffer-fish was developed. Tetrodotoxin in puffer-fish was extracted with 0.1% acetic acid by heating in a boiling water bath, and the extracts were cleaned up on a Bond Elut C18 (500 mg) cartridge. The LC separation was performed on a TSK-gel ODS 80Ts column (25 cm×2 mm i.d.) using 5 mmol/L heptafluoro-n-butyric acid (HFBA)-methanol (99 : 1) as the mobile phase at a flow rate of 0.2 mL/min. Positive ionization produced a typical [M+H]+ molecular ion of tetrodotoxin (m/z 320.1). The calibration graph for tetrodotoxin was rectilinear from 0.1 to 1 μg/mL with selected ion monitoring (SIM). The detection limit of tetrodotoxin in puffer-fish was 1 μg/g (equivalent to ca. 5 MU/g).View full abstractDownload PDF (657K) -
Yoichi ONOUE, Rie SHINDO, Hiroshi TERANISHI, Ichiro FURUKAWA, Yukie HA ...2002 Volume 43 Issue 4 Pages 239-242
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSThe efficacy of Baird-Parker (BP) agar, mannitol-salt-egg yolk (MSEY) agar and mannitol salt (MS) agar in detecting Staphylococcus aureus FRI-100 heated at 52°C for 20 min in 100 mmol/L potassium phosphate buffer was determined. Brain heart infusion agar with 1% pyruvate (BHIP agar) supported the highest recovery of injured cells and was used as the control medium.
Of the three selective media, significantly higher recovery of heat-injured cells was observed on BP agar than MSEY agar, and the poorest recovery was observed on MS agar (p<0.05). Low recovery of unheated cells was obtained for MS compared with other media (p<0.05). A reduction in populations occurred gradually in reagent-grade water stored for 14 days at -20°C. There was no significant difference between BHIP agar and MS agar in the number of freeze-injured cells recovered from 1 to 14 days.View full abstractDownload PDF (363K) -
Masaru SAITOH, Kiyomi ASAKA, Miho ARAI, Akira KAWABATA, Sekio KANOH, T ...2002 Volume 43 Issue 4 Pages 243-249
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSIn order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students.
Fifteen (15.3%) of the 98 students were sensitized to SEA and / or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p<0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p<0.05), and a negative correlation (p<0.001) was recognized between the neutrophil and the lymphocyte rates.View full abstractDownload PDF (571K) -
Naoki SUGIMOTO, Kyoko SATO, Hong-Min LIU, Hiroyuki KIKUCHI, Takeshi YA ...2002 Volume 43 Issue 4 Pages 250-253
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSThe main and minor constituents of tenryocha extract product, a natural sweetener, were investigated as a part of an ongoing study to evaluate its quality and safety as a food additive. Four constituents, namely rubusoside, steviolmonoside, panicloside IV, and ent-16α,17-dihydroxykauran-19-oic acid, were isolated. The concentration of rubusoside, the main sweet constituent, was 8.65% in the tenryocha extract product. In addition, it was confirmed that the origin of the extract was the leaves of Rubus suavissimus S. LEE (Rosaseae), as determined by comparing TLC and HPLC profiles of the product and hot-water extract prepared from the leaves of R. suavissimus.View full abstractDownload PDF (166K)
Reports
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Yukari TSUMURA, Susumu ISHIMITSU, Kuni HIRAYAMA, Teruhisa FUJIMAKI, Hi ...2002 Volume 43 Issue 4 Pages 254-259
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSThree samples of polyvinyl chloride products for food use were examined for di(2-ethylhexyl) phthalate (DEHP) migration levels under the conditions described in the Japanese Food Sanitation Law. These samples were two kinds of tubes and one stretched film, containing 12 to 41% DEHP by weight. DEHP migration levels from them were very low, all below 0.1 ppm, into 3 kinds of food simulant; water, 4% acetic acid and 20% ethanol. However, high levels of DEHP migrated into n-heptane, 12 ppm from the stretched film sample and more than 800 ppm from the tube samples. Migration from the 2 tubes was higher than 150 ppm, the limit of residues after evaporation in containers and wraps. Though the limit of residues after evaporation is not set for equipment used in the preparation of foods, the tested tubes were considered to be unsuitable for uses in which they come into direct contact with oils, fats or oily foods.View full abstractDownload PDF (2698K) -
Asako OZAKI, Yukihiko YAMAGUCHI, Akiyoshi OKAMOTO, Nobuko KAWAI2002 Volume 43 Issue 4 Pages 260-266
Published: August 25, 2002
Released on J-STAGE: April 30, 2009
JOURNAL FREE ACCESSInfants, whose growth and development are highly dependent upon the endocrine system, are particularly vulnerable to endocrine disruptor exposure. In our study, we examined whether or not alkylphenols, bisphenol A, benzophenone, di(2-ethylhexyl)adipate and 10 phthalates are present in containers of baby food. Furthermore, the migration into food-simulating solvents was also examined. Sixteen types of containers of baby food, obtained on the Japanese market in 2001, were examined: 8 glass bottle types, 1 plastic type, 1 metallic package (laminated with plastic) and 6 multilayered laminated film packages. Alkylphenols, benzophenone, bisphenol A and di(2-ethylhexyl)adipate were not detected in any of the samples. On the other hand, dibutylphthalate (DBP) was detected in 7 samples (1.2∼9.1 μg/sample), and di(2-ethylhexyl)phthalate (DEHP) was detected in 15 samples (1.3∼18 μg/sample). Migration tests were carried out for 5 samples, and the levels of DBP and DEHP that migrated into n-heptane were 0.68∼1.7 μg/sample and 0.33∼3.5 μg/sample, respectively. From these results, a baby's intake levels of DBP and DEHP were estimated to be about 1/2,500 and 1/90∼300 of the tolerable daily intake (TDI), respectively.View full abstractDownload PDF (608K)
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