All issues
Volume 49, Issue 1
Displaying 1-9 of 9 articles from this issue
- |<
- <
- 1
- >
- >|
Review
-
Yoshiko KONISHI, Kei-ichi SUGIYAMA2008 Volume 49 Issue 1 Pages 1-10
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSDownload PDF (1186K)
Originals
-
Jun KUDAKA, Kiyomasa ITOKAZU, Katsuya TAIRA, Minoru NIDAIRA, Sho OKANO ...2008 Volume 49 Issue 1 Pages 11-15
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSCaulerpa lentillifera is a kind of edible seaweed, known as ‘sea grape’ or ‘green caviar’. It is used in fresh salads. However, it is sensitive to low temperature and osmotic pressure, and is easily spoilt by storage in a refrigerator or washing with tap water. That is the reason why it is difficult to prevent food poisoning, especially due to Vibrio parahaemolyticus. In this study we investigated of marine bacteria and V. parahaemolyticus in C. lentillifera and cultured them in order to develop effective control of bacteria in commercial farms. The sixteen farms in the Okinawa Islands were investigated from August to September in 2006. A total of 176 samples were collected from eleven points during the cultivation processes and from the products. About 103 cfu/mL of marine bacteria were detected in the seawater used in the tank culture, but after cultivation of C. lentillifera the number had increased to about 106 cfu/mL. The number of marine bacteria in C. lentillifera did not change significantly through the process of planting to the final product (about 107 cfu/g). V. parahaemolyticus was detected in seawater from all processes and C. lentillifera was isolated from 56% of seawater, 25% of seed-stocks, and 18.8% of product samples, though but thermostable direct hemolysin gene was not detected from enrichment cultures or isolated V. parahaemolyticus strains. These results indicate that for prevention of food poisoning by V. parahaemolyticus in C. lentillifera, it is important to establish a suitable sterilization procedure for each process.View full abstractDownload PDF (961K) -
Taichi OGUCHI, Mari ONISHI, Yukie CHIKAGAWA, Yasutaka MINEGISHI, Takas ...2008 Volume 49 Issue 1 Pages 16-22
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSA real-time PCR detection method was developed for event-specific quantitation of Roundup Ready® maize, GA21. The developed PCR method was designed to amplify an artificial junction site between the native maize genome DNA and the recombinant DNA of GA21 maize, which provides only one target sequence per haploid of GA21 genome. Thus, the amplification efficiency of the event-specific target for GA21 became closely similar to the amplification of SSIIb, and the conversion factor (Cf) for the quantitation method was similar to the theoretical value. The developed method demonstrated better performance than the existing construct-specific method that has been used as a Japanese official method. The developed method can easily be combined with the real-time PCR targeting of the CaMV35S promoter, and the multiplexed method should be an effective screening method for GM maize.View full abstractDownload PDF (1159K) -
Hiroyuki HASHIMOTO, Yuhki MAKABE, Yasuyuki HASEGAWA, Junko SAJIKI, Fum ...2008 Volume 49 Issue 1 Pages 23-30
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSA nested PCR method was developed for the detection of DNAs extracted from allergenic substances (here, wheat) in food. Because of DNA fragmentation, detection of wheat-specific DNA extracted from food, such as retort pouch food, is very difficult. Therefore, to improve the sensitivity of detection, a nested PCR primer pair (Wtr01NE2-5' and Wtr10NE5-3': amplicon size 97 bp) was newly designed within the region of the PCR products amplified by the official Japanese primer pair (Wtr01-5' and Wtr10-3'; amplicon size 141 bp) for wheat. Genomic DNAs of seven kinds of commercial processed foods containing wheat, wheat flour and three kinds of wheat flours pressure-heated at 100, 121 and 131°C were extracted with a commercial ion-exchange type kit by modifying the Japanese official method. The nested PCR method involved two PCR procedures. First, PCR was performed by varying both the PCR reagents and cycling conditions of the Japanese official method. Second, PCR was performed using the first PCR products diluted 200-fold with TE buffer. The Japanese official method enabled detection of only four of the seven kinds of foods and three of the four kinds of flours (one sample was just a trace), while the nested PCR method detected all seven foods and all four flours. Investigation of the detectability of the four kinds of wheat flours depending on the size of the amplified fragment using five primer pairs showed that its size must be kept to less than approximately 100 bp. The nested PCR method significantly improved the sensitivity of detection of wheat-specific DNA.View full abstractDownload PDF (922K) -
Hiroko MATSUMOTO, Keiko HIRATA, Narue SAKAMAKI, Kayo HAGINO, Hirofumi ...2008 Volume 49 Issue 1 Pages 31-36
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSSimultaneous determination of three artificial sweeteners, neotame (NE), alitame (AL) and aspartame (APM) in various foods by high-performance liquid chromatography (HPLC) was developed. Chopped or homogenized samples were packed into cellulose tubing with 0.01 mol/L hydrochloric acid containing 10% sodium chloride, and dialyzed against 0.01 mol/L hydrochloric acid for 24-48 hours. The dialyzate was passed through an Oasis® MCX cartridge, and the cartridge was washed with water and methanol. Then the three sweeteners were eluted from the cartridge with a mixture of 0.5 mol/L ammonium chloride-acetonitrile (3 : 2). The sweeteners were separated on a Cosmosil 5C18-AR column using a gradient mode with a mobile phase of 0.01 mol/L phosphate buffer (pH 4.0)-acetonitrile and were detected at 210 nm.
The recoveries of NE, AL and APM from 8 kinds of foods spiked with 10 and 100 μg/g were 86-100% and 89-104%, respectively. The detection limits of NE, AL and APM were 1 μg/g in samples. Furthermore, the three sweeteners were successfully identified by using liquid chromatography with tandem mass spectrometry.View full abstractDownload PDF (648K) -
Maki KANDA, Tomoko KUSANO, Taka OSANAI, Keiko USHIYAMA, Kazue TAKEBA, ...2008 Volume 49 Issue 1 Pages 37-44
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSA rapid and precise determination residues of 4 tetracyclines (TCs) (oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DOXY)) in meat was developed by employing three analyses; a microbiological screening, HPLC and LC/MS/MS. TCs were extracted with pH 4.0 McIlvaine buffer containing 0.01 mol/L EDTA from a meat sample, and then purified using a mixed mode, reversed-phase and cation-exchange cartridge. The mean recoveries (n=5) of 0.2 μg/g OTC, TC and CTC, 0.05 μg/g DOXY spiked in meat samples were 76.6-99.0% (C.V. 1.6-5.4%). In 13 meat samples in which the microbiological screening indicated the presence of TCs, CTC (9 samples) and DOXY (4 samples) were identified with HPLC and LC/MS/MS.View full abstractDownload PDF (659K)
Notes
-
Kiyomi OHMORI, Hisayo TSUCHIYA, Takahiro WATANABE, Hiroshi AKIYAMA, Ta ...2008 Volume 49 Issue 1 Pages 45-50
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSThe yield of genomic DNA extracted from corn-processed foods, such as corn flake and one of the corn snack what is called “Jumbo corn”, using an ion-exchange resin type kit (Gtip) has been reported to be very low, and it is thought to be difficult to detect the intrinsic corn gene “Zein” in the foods. Therefore, we developed a new method using Gtip, which we called the “KNG-Gtip method,” by modification of the Ministry of Health, Labour and Welfare (MHLW) method using Gtip (MHLW-Gtip method). We compared the KNG-Gtip method, MHLW-Gtip method, the Gtip method for detection of allergen (ALG-Gtip method), and the Gtip method according to the Ministry of Agriculture, Forestry and Fisheries (MAFF) (JAS-Gtip method) in terms of the yield and quality of genomic DNA and the detection probabilities of the PCR-amplified Zein gene. The concentrations of DNA and the detection probabilities of the PCR-amplified Zein gene of genomic DNA extracted from 4 g corn flake and 4 g Jumbo corn by the KNG-Gtip method were larger than those by using the conventional methods. In addition, the PCR-amplified Zein gene from 4 g of corn starch could be detected by the KNG-Gtip method. We propose that the KNG-Gtip method, in which requires sample weight of four grams, is practical and useful to extract genomic DNA from corn flake and Jumbo corn.View full abstractDownload PDF (1013K) -
Tsutomu FUKUWATARI, Katsumi SHIBATA2008 Volume 49 Issue 1 Pages 51-55
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSIn order to determine the tolerable upper intake level of folic acid in humans, we investigated the effects of excessive folic acid administration on the body weight gain, food intake, tissue weight, and metabolism of B-group vitamins in weaning rats. The rats were freely fed ordinary diet containing 0.0002% folic acid (control diet) or the same diet with 0.01%, 0.1%, or 1.0% folic acid for 29 days. The body weight gains and food intakes did not differ among the four groups. Diarrhea was not seen even in the 1.0% group. Excess folic acid did not affect the tissue weights of the brain, heart, liver, kidney, spleen, lung, or testis, or urinary excretion of other B-group vitamins. These results clearly showed that feeding a diet containing up to 1.0% folic acid did not affect the food intake, body weight gain, tissue weight, or urinary excretion of B-group vitamins in weaning rats.View full abstractDownload PDF (513K)
Report
-
Naoki SUGIMOTO, Atsuko TADA, Masanori KUROYANAGI, Yuko YONEDA, Young S ...2008 Volume 49 Issue 1 Pages 56-62
Published: February 29, 2008
Released on J-STAGE: March 14, 2008
JOURNAL FREE ACCESSGrapefruit seed extract (GSE), derived from the seeds of grapefruit (Citrus paradisi MCAF.), is listed as a natural food additive in Japan. Products containing GSE are used as disinfectants made from only natural sources, especially after Japanese researchers found that GSE prevents the growth of norovirus. On the other hand, recent overseas studies indicated that synthetic disinfectants, such as benzalkonium and benzethonium chlorides, were present in some commercial GSE products. To confirm the quality of commercial GSE products available in Japanese markets, we carried out comprehensive research to identify the major constituents of commercial GSE products which are used as food additives (13 products from 6 manufacturers), dietary supplements (5 products from 4 manufacturers), cosmetic materials (16 products from 10 manufacturers) and disinfectant or deodorant sprays (7 products from 7 manufacturers). By means of NMR and LC/MS analysis, synthetic disinfectants such as benzethonium or benzalkonium salts were detected in most of the commercial GSE products.View full abstractDownload PDF (599K)
- |<
- <
- 1
- >
- >|