Campylobacter (cdt gene) PCR Detection and Typing Kit (以下，Campylobacter PCR Kit) が食品からのカンピロバクターの迅速検査に有用であるかを評価するために，市販鶏肉およびカンピロバクターを接種した鶏肉検体から分離培養法およびCampylobacter PCR Kitを用いて検査を行った．2種類の増菌培地と3種類の分離培養法の組み合わせで市販鶏肉24検体中，21検体と7検体からC. jejuni, あるいはC. coliが分離された．そのうち通常の食肉検査に用いる培養法，すなわちBoltonまたはPreston培地とmCCDAの組み合わせでではC. jejuni, あるいはC. coliが分離された検体のうちC. jejuniおよびC. coliがそれぞれ19検体(90%)および5検体(71%) から分離された．一方，Campylobacter PCR Kitを用いるとC. jejuniに関してはPrestonによる24時間の増菌培養でC. jejuniが分離された21検体のすべてからC. jejuniを検出することができた．C. coliに関してはBoltonとPrestonによる48時間の増菌培養の組み合わせでC. coliが分離された7検体のうち6検体からC. coliを検出することができた．また， C. coliが分離されなかった1検体からCampylobacter PCR KitではC. coliを検出することができた．さらに，スパイク実験より精製DNAとCampylobacter PCR Kitを用いることで，10²オーダーの菌を増菌培養開始後24時間以内に菌種特異的に検出できた．以上の結果よりCampylobacter (cdt gene) PCR Detection and Typing Kit はカンピロバクターの迅速検査として有用であると考えられた．

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Ochratoxin A (OTA) is one of the most important mycotoxins because of its nephrotoxicity and possible carcinogen in human and animals. OTA is produced by several species in the fungal genera Aspergillus and Penicillium, mainly A. carbonarius, A. ochraceus and P. verrucosum. However, recently the majority of toxigenic isolates identified as A. ochraceus in earlier studies were split as segregate species (A. westerdijkiae or A. steynii) from A. ochraceus.
In this paper, species identification of the food-borne isolates that were formerly reported as A. ochraceus in Japan was carried out on the basis of conventional and phylogenetical analyses. Among a total of 21 isolates examined, 18 isolates from green coffee beans and one isolate from spoiled soy bean were newly identified as A. westerdijkiae, while each one isolate from domestic moldy rice and from fish processed product were newly identified as A. steynii. Most of these isolates were found to be able to produce OTA on yeast extract-sucrose agar (YES) medium in the range of 82–1,400 μg/g. Hence, it is possible that the majority of toxigenic isolates that were reported as A. ochraceus in earlier Japanese studies were actually A. westerdijkiae or A. steynii.

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The characteristics of extended-spectrum β-lactamase (ESBL) producing Escherichia coli strains derived from domestic animals, chicken meat and humans were examined. ESBL-producing strains were isolated from 4 (4.0%) of 100 cattle fecal samples, 4 (4.0%) of 100 swine fecal samples, 14 (23.3%) of 60 chicken samples and 18 (7.2%) of 249 human fecal samples. A total of 40 ESBL-producing E. coli strains (5 bovine-derived strains, 3 swine-derived strains, 14 chicken-derived strains and 18 human-derived strains) were characterized. By molecular typing of ESBL genes, blaCTX-M-15 (CTX-M-1 group) and blaCTX-M-14 (CTX-M-9 group) were commonly found in bovine, swine, chicken and human-derived strains; blaSHV-12 was a dominant type in chicken-derived strains. Among those 40 strains, 6 strains were belonged to five different serotypes: O78 : H9 (2 chicken-derived strains), O6 : H untypeable (1 chicken-derived strain), O1 : H45 (1 chicken-derived strain), O25 : H4 (1 human-derived strain) and O86a : H4 (1 human-derived strain). The antimicrobial sensitivity test using 12 different antimicrobial agents by disc diffusion method (ampicillin, cefepime, cefmetazole, imipenem, fosfomycin, streptomycin, kanamycin, chloramphenicol, tetracycline, nalidixic acid, norfloxacin and sulfamethoxazole-trimethoprim) revealed that all 40 strains were sensitive to cefepime, cefmetazole, imipenem, and fosfomycin; 6 strains (1 bovine-derived strain, 4 chicken-derived strains and 1 human-derived strain) were resistant to only ampicillin and other 34 strains showed multi-drug resistance to 2 to 6 agents. Genotyping by pulsed-field gel electrophoresis revealed that the 40 strains were very diverse and heterogeneous.

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In this study, we aimed to evaluate the usability of some genetic markers which were previously reported the capability to identify Fusarium isolates based on barcording with nucleotide sequences, and to clear up the questionable points of application for actual isolates. We constructed a local database containing 46 reference sequences of Fusarium strains already-identified, and sequenced six genetic regions of 19 food-borne Fusarium isolates. And then, the nucleotide sequence homologies of each genetic region were calculated pairwisely between an isolate and a reference strain. The 18S rDNA, 5.8S rDNA, 28S rDNA and ITS1 sequences leaded to the accurate identification of only three to 13 isolates, respectively, because of perfect matches to sequences of more than two species of reference strains, or mis-identification. The lys2 sequences leaded to the accurate identification of several isolates not identified by these four regions. However, other five isolates could not be identified because of non-amplification of lys2 by PCR. The β-tub sequences leaded to the accurate identification of all tested-isolates. Thus, the β-tub is more useful genetic marker for identifying Fusarium isolates in a wide range than other five loci including lys2.

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市販の低塩分および高塩分イカ塩辛および自家製低塩分イカ塩辛において，腸炎ビブリオの汚染と一般細菌数の変化を検討した．いずれのイカ塩辛においても，腸炎ビブリオの汚染は確認されなかった．市販品および自家製の低塩分イカ塩辛を25℃で培養すると一般細菌数が48時間で1,000倍近くまで増加したが，高塩分のイカ塩辛では一般細菌数は一定に維持されていた．それらのイカ塩辛に腸炎ビブリオを接種して，その増殖を検討したが，どのタイプのイカ塩辛においても，腸炎ビブリオの菌数の増加は見られず死滅した．本研究において低塩分のイカ塩辛でも腸炎ビブリオが死滅したことから，その生育および増殖の要因としてイカ塩辛の塩分濃度だけでなく，水分活性や添加物の影響も検討する必要があると考えられた．

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