Recently, an instrumental analysis using LC-MS/MS has been developed and validated for paralytic shellfish toxins (PSTs) and tetrodotoxin (TTX) in bivalve molluscs in Japanese domestic and overseas. The method for 11 PSTs and TTX in scallops was validated in accordance with a previous report and CODEX-STAN. The samples were prepared by adding the standard mixture of PSTs and TTX to scallop (Patinopecten yessoensis) homogenates, extracted with 1% acetic acid and then cleaned up using an ENVI-Carb (250 mg/3 mL) cartridge. A single analyst extracted and analyzed in two samples per day on five successive days. As result of the validation, 11 PSTs were found falling within all the guideline criteria (the trueness, repeatability, within laboratory reproducibility, LOD, LOQ) in the tests using matrix-matched calibration or solvent calibration.However, the trueness of TTX was low value in the test using solvent standard. It would be due to the matrix effects at the LC-MS/MS analysis. The slope of the calibration curve at the matrix-matched standards of mussel was about the same as the slope at the solvent standards. Therefore, it is necessary to choose the most appropriate matrix depending on shellfish.
{"title":"[Validation Study of LC-MS/MS for Paralytic Shellfish Toxins and Tetrodotoxin in Scallops].","authors":"Satoshi Numano, Ryuichi Watanabe, Mayu Ozawa, Hajime Uchida, Ryoji Matsushima, Toshiyuki Suzuki","doi":"10.3358/shokueishi.65.129","DOIUrl":"https://doi.org/10.3358/shokueishi.65.129","url":null,"abstract":"<p><p>Recently, an instrumental analysis using LC-MS/MS has been developed and validated for paralytic shellfish toxins (PSTs) and tetrodotoxin (TTX) in bivalve molluscs in Japanese domestic and overseas. The method for 11 PSTs and TTX in scallops was validated in accordance with a previous report and CODEX-STAN. The samples were prepared by adding the standard mixture of PSTs and TTX to scallop (Patinopecten yessoensis) homogenates, extracted with 1% acetic acid and then cleaned up using an ENVI-Carb (250 mg/3 mL) cartridge. A single analyst extracted and analyzed in two samples per day on five successive days. As result of the validation, 11 PSTs were found falling within all the guideline criteria (the trueness, repeatability, within laboratory reproducibility, LOD, LOQ) in the tests using matrix-matched calibration or solvent calibration.However, the trueness of TTX was low value in the test using solvent standard. It would be due to the matrix effects at the LC-MS/MS analysis. The slope of the calibration curve at the matrix-matched standards of mussel was about the same as the slope at the solvent standards. Therefore, it is necessary to choose the most appropriate matrix depending on shellfish.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 5","pages":"129-135"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142856819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.3358/shokueishi.65.20
Nobuyuki Wakui, Koichi Inoue, Mari Nunome, Yoshinari Suzuki, Aya Takagi, Rie Ito, Yusuke Iwasaki, Junkichi Sugiura, Hiroshi Akiyama
In this study, a public seminar on risk communication methods was conducted to raise awareness and disseminate accurate knowledge about residual pesticides to consumers. Additionally, surveys on consumer awareness were conducted on the attendees before and after the seminar to evaluate its effectiveness. Responses were obtained from 84 participants. The paired t-test was used to analyze the changes in awareness before and after the seminar. The results showed significant improvements in "trust in the government" and "understanding of residual pesticides." Furthermore, step-wise multiple regression analysis was performed to explore the factors influencing satisfaction with the risk communication seminar, and the item "understanding of the safety of residual pesticides in food" was extracted. Understanding food safety is a crucial concern in daily life for consumers. To enable consumers to have an accurate understanding of food risks and make appropriate judgments, it is essential to continue implementing risk communication and conveying information about food safety and security in the future.
{"title":"[Implementation and Evaluation of Risk Communication Regarding Residual Pesticides].","authors":"Nobuyuki Wakui, Koichi Inoue, Mari Nunome, Yoshinari Suzuki, Aya Takagi, Rie Ito, Yusuke Iwasaki, Junkichi Sugiura, Hiroshi Akiyama","doi":"10.3358/shokueishi.65.20","DOIUrl":"10.3358/shokueishi.65.20","url":null,"abstract":"<p><p>In this study, a public seminar on risk communication methods was conducted to raise awareness and disseminate accurate knowledge about residual pesticides to consumers. Additionally, surveys on consumer awareness were conducted on the attendees before and after the seminar to evaluate its effectiveness. Responses were obtained from 84 participants. The paired t-test was used to analyze the changes in awareness before and after the seminar. The results showed significant improvements in \"trust in the government\" and \"understanding of residual pesticides.\" Furthermore, step-wise multiple regression analysis was performed to explore the factors influencing satisfaction with the risk communication seminar, and the item \"understanding of the safety of residual pesticides in food\" was extracted. Understanding food safety is a crucial concern in daily life for consumers. To enable consumers to have an accurate understanding of food risks and make appropriate judgments, it is essential to continue implementing risk communication and conveying information about food safety and security in the future.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 1","pages":"20-23"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140023332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ciguatera poisoning (CP) is one of the most frequent seafood poisonings across the globe. CP results from the consumption of fish flesh that has accumulated principal toxins known as ciguatoxins (CTXs), and it mainly occurs in tropical and subtropical regions. In Japan, incidents of CP have been reported primarily from Okinawa and Amami Islands in the subtropical area. Meanwhile, there have also been reports from Mainland sporadically. Since the amount of CTXs contained in fish flesh is extremely low, a highly sensitive detection method by LC-MS/MS is required. But the currently reported detection method is applicable only to specific equipment, and many laboratories have difficulty to respond CP. In this study, to prepare for the risk of nationwide CP, we researched a universal analytical method for CTXs based on LC-MS/MS. Using a water/acetonitrile mobile phase supplemented with lithium hydroxide and formic acid gave rise to prominent peaks of the stable [M+Li]+ions. As the [M+Li]+ions did not produce valid product ions even with high collision energy, the [M+Li]+ions of each analog were set for both precursor and product ions ([M+Li]+>[M+Li]+) and monitored under the multiple reaction monitoring (MRM) mode. With the method described above, analyses of nine CTX congeners were carried out. The limit of detection (LOD, S/N>5) and quantitation (LOQ, S/N>10) were estimated as 0.005-0.030 ng/mL and 0.010-0.061 ng/mL, respectively. When the 1 mL of extract solution is prepared from 5 g of the fish tissue, the LOD and LOQ will be at 0.001-0.006 μg/kg and 0.002-0.012 μg/kg, respectively. This result indicates that we could detect the required level of 0.175 μg/kg CTX1B equivalent in fish flesh which is recommended for safe consumption in Japan. This method is considered to be a universal analytical method without depending on the specific equipment. Thus it could contribute to improving the CP investigations in nationwide laboratories.
{"title":"[Universal Method for Determination of Ciguatoxins by LC-MS/MS].","authors":"Kyohei Yamada, Hiroshi Shitara, Noriko Kanda, Takahide Kondo, Michihiro Nishida, Naomasa Oshiro","doi":"10.3358/shokueishi.65.72","DOIUrl":"10.3358/shokueishi.65.72","url":null,"abstract":"<p><p>Ciguatera poisoning (CP) is one of the most frequent seafood poisonings across the globe. CP results from the consumption of fish flesh that has accumulated principal toxins known as ciguatoxins (CTXs), and it mainly occurs in tropical and subtropical regions. In Japan, incidents of CP have been reported primarily from Okinawa and Amami Islands in the subtropical area. Meanwhile, there have also been reports from Mainland sporadically. Since the amount of CTXs contained in fish flesh is extremely low, a highly sensitive detection method by LC-MS/MS is required. But the currently reported detection method is applicable only to specific equipment, and many laboratories have difficulty to respond CP. In this study, to prepare for the risk of nationwide CP, we researched a universal analytical method for CTXs based on LC-MS/MS. Using a water/acetonitrile mobile phase supplemented with lithium hydroxide and formic acid gave rise to prominent peaks of the stable [M+Li]+ions. As the [M+Li]+ions did not produce valid product ions even with high collision energy, the [M+Li]+ions of each analog were set for both precursor and product ions ([M+Li]+>[M+Li]+) and monitored under the multiple reaction monitoring (MRM) mode. With the method described above, analyses of nine CTX congeners were carried out. The limit of detection (LOD, S/N>5) and quantitation (LOQ, S/N>10) were estimated as 0.005-0.030 ng/mL and 0.010-0.061 ng/mL, respectively. When the 1 mL of extract solution is prepared from 5 g of the fish tissue, the LOD and LOQ will be at 0.001-0.006 μg/kg and 0.002-0.012 μg/kg, respectively. This result indicates that we could detect the required level of 0.175 μg/kg CTX1B equivalent in fish flesh which is recommended for safe consumption in Japan. This method is considered to be a universal analytical method without depending on the specific equipment. Thus it could contribute to improving the CP investigations in nationwide laboratories.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 3","pages":"72-77"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141735673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We assessed the applicability of high-performance liquid chromatography (HPLC) to the official testing method for the migration of caprolactam (CPL) from food utensils, containers, and packaging made from polyamide (PA). Hydrophilic interaction chromatography (HILIC) columns coated with unmodified silica, carbamoyl, and aminopropyl were used. Water and acetonitrile (ACN) were used as the mobile phase, and the analytical conditions were optimized. The test solution was diluted 10-fold with ACN, and standard solutions were prepared using 98% ACN. We validated using HPLC as limit testing and quantitative testing methods. Accuracy parameters corresponding to trueness, repeatability, and reproducibility (as intermediate precision) satisfied the target values in both cases, indicating that this method demonstrates good performance as a testing method.
{"title":"[Application of High-performance Liquid Chromatography to Caprolactam Migration Testing of Food Utensils, Containers, and Packaging].","authors":"Yutaka Abe, Miku Yamaguchi, Koji Fujihara, Yohei Kataoka, Motoh Mutsuga, Naoki Sugimoto","doi":"10.3358/shokueishi.65.107","DOIUrl":"10.3358/shokueishi.65.107","url":null,"abstract":"<p><p>We assessed the applicability of high-performance liquid chromatography (HPLC) to the official testing method for the migration of caprolactam (CPL) from food utensils, containers, and packaging made from polyamide (PA). Hydrophilic interaction chromatography (HILIC) columns coated with unmodified silica, carbamoyl, and aminopropyl were used. Water and acetonitrile (ACN) were used as the mobile phase, and the analytical conditions were optimized. The test solution was diluted 10-fold with ACN, and standard solutions were prepared using 98% ACN. We validated using HPLC as limit testing and quantitative testing methods. Accuracy parameters corresponding to trueness, repeatability, and reproducibility (as intermediate precision) satisfied the target values in both cases, indicating that this method demonstrates good performance as a testing method.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 5","pages":"107-112"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142856724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.3358/shokueishi.65.172
Toru Fukumitsu, Masahito Hagio, Kenichi Kumasaka
In this study, a rapid and accurate analytical method was developed for the simultaneous determination of 26 plant toxins and 11 mushroom toxins in toxic plants, toxic mushrooms, and their cooked products using LC-MS/MS. This method enables highly selective detection of all 37 analytes, including those with high polarity and low molecular weight, within 10 min using Scherzo SS-C18 column. The analytes were extracted from the samples using methanol and trichloroacetic acid, and purified using Captiva EMR-Lipid. A 50 vol% methanol solution was used as the test solvent, to minimize matrix effects. Validation with six types of food samples demonstrated recoveries ranging from 56.0% to 180.5% (with 96% or more of analytes achieving 70-120%) and RSD of 16.0% or less (with 98% or more of analytes achieving 10% or less), at an added concentration of 1 mg/kg. These results indicate that this method is effective for health crisis management. Additionally, the method successfully detected expected toxins in food leftovers and reference products implicated in previous health hazard cases.
{"title":"[Development of a Rapid Analytical Method for Simultaneous Determinationof Diverse Plant and Mushroom Toxins].","authors":"Toru Fukumitsu, Masahito Hagio, Kenichi Kumasaka","doi":"10.3358/shokueishi.65.172","DOIUrl":"10.3358/shokueishi.65.172","url":null,"abstract":"<p><p>In this study, a rapid and accurate analytical method was developed for the simultaneous determination of 26 plant toxins and 11 mushroom toxins in toxic plants, toxic mushrooms, and their cooked products using LC-MS/MS. This method enables highly selective detection of all 37 analytes, including those with high polarity and low molecular weight, within 10 min using Scherzo SS-C18 column. The analytes were extracted from the samples using methanol and trichloroacetic acid, and purified using Captiva EMR-Lipid. A 50 vol% methanol solution was used as the test solvent, to minimize matrix effects. Validation with six types of food samples demonstrated recoveries ranging from 56.0% to 180.5% (with 96% or more of analytes achieving 70-120%) and RSD of 16.0% or less (with 98% or more of analytes achieving 10% or less), at an added concentration of 1 mg/kg. These results indicate that this method is effective for health crisis management. Additionally, the method successfully detected expected toxins in food leftovers and reference products implicated in previous health hazard cases.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 6","pages":"172-177"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A method was developed for determining five organochlorine unstable pesticides (captan, chlorothalonil, dichlofluanid, folpet, and tolylfluanid) in agricultural products using GC-MS/MS. To prevent pesticide degradation, the food sample was maintained at -20℃ until the initiation of the extraction process. The sample underwent homogenization with acetonitrile and salting out using anhydrous magnesium sulfate and sodium chloride in the presence of citrate salts. Cleanup was executed using Graphite Carbon and C18 SPE cartridges. The validation of this method was tested on five agricultural products at two concentrations (0.01 and 0.1 μg/g). The recovery rates varied between 86.7% and 96.1%. RSDs for repeatability were less than 15.2% and 8.8%, while the RSDs for within-laboratory reproducibility were under 19.9% and 12.7%. These results meet the criteria established by the validation guidelines in Japan.
{"title":"[Single-Laboratory Validation Study of Simultaneous Determination Methodfor Five Organochlorine Unstable Pesticides in Agricultural Products by GC-MS/MS].","authors":"Yoshihiro Ohsawa, Sanae Tomizawa, Kyoko Kamijo, Takayuki Nakajima, Kazuoki Yamamoto, Tomomi Takada, Yoshie Kokaji, Hiroko Shiradoh, Ayane Oyama, Maiko Noguchi, Tomoko Yokoyama","doi":"10.3358/shokueishi.65.124","DOIUrl":"https://doi.org/10.3358/shokueishi.65.124","url":null,"abstract":"<p><p>A method was developed for determining five organochlorine unstable pesticides (captan, chlorothalonil, dichlofluanid, folpet, and tolylfluanid) in agricultural products using GC-MS/MS. To prevent pesticide degradation, the food sample was maintained at -20℃ until the initiation of the extraction process. The sample underwent homogenization with acetonitrile and salting out using anhydrous magnesium sulfate and sodium chloride in the presence of citrate salts. Cleanup was executed using Graphite Carbon and C18 SPE cartridges. The validation of this method was tested on five agricultural products at two concentrations (0.01 and 0.1 μg/g). The recovery rates varied between 86.7% and 96.1%. RSDs for repeatability were less than 15.2% and 8.8%, while the RSDs for within-laboratory reproducibility were under 19.9% and 12.7%. These results meet the criteria established by the validation guidelines in Japan.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 5","pages":"124-128"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142856807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Since the establishment of procedures for the safety assessment of food products that use recombinant DNA technology, the manufacture, import, and sale of genetically modified (GM) foods that have not undergone safety assessment are prohibited under the Food Sanitation Act. Therefore, a performance study to confirm the GM food testing operations of each laboratory is very important to ensure the reliability of the GM food monitoring system. In 2022, GM papaya line PRSV-YK-which has not yet been authorized in Japan-was selected for testing, and a papaya paste and a DNA solution were used as the test samples. With these samples, a laboratory performance study of the DNA extraction and real-time PCR operations was conducted. This confirmed that the 18 participating laboratories were generally performing the DNA extraction and real-time PCR operations correctly. However, some laboratories using certain DNA amplification reagent with some real-time PCR instruments were not able to determine the PRSV-YK detection test. This suggests that the PRSV-YK detection test may not be able to correctly detect samples containing GM papaya when performed with these combinations of instruments and reagent. In order to ensure the reliability of the PRSV-YK detection test, it is necessary to examine in detail how the combination of DNA polymerase reagents and real-time PCR instruments affects the detection limit, and to implement an appropriate solution.
自从制定了使用重组 DNA 技术的食品安全评估程序以来,《食品卫生法》禁止生产、进口和销售未经安全评估的转基因食品。因此,为确保转基因食品监测系统的可靠性,进行绩效研究以确认各实验室的转基因食品检测业务非常重要。2022 年,日本选择了尚未获得授权的转基因木瓜品系 PRSV-YK 进行检测,并使用木瓜糊和 DNA 溶液作为检测样本。利用这些样品,对 DNA 提取和实时 PCR 操作进行了实验室性能研究。结果表明,18 个参与实验室的 DNA 提取和实时 PCR 操作基本正确。然而,一些实验室在使用某些 DNA 扩增试剂和某些实时 PCR 仪器时,无法确定 PRSV-YK 检测测试结果。这表明,在使用这些仪器和试剂组合时,PRSV-YK 检测试验可能无法正确检测出含有转基因木瓜的样品。为了确保 PRSV-YK 检测试验的可靠性,有必要详细研究 DNA 聚合酶试剂和实时 PCR 仪器的组合如何影响检测限,并采取适当的解决方案。
{"title":"[Laboratory Performance Study of the Japanese Official Method to Detect Genetically Modified Papaya Line PRSV-YK].","authors":"Norihito Shibata, Toshiaki Nakasaka, Jumpei Narushima, Chie Taguchi, Miyu Sugino, Satoko Yoshiba, Keisuke Soga, Michika Kajiwara, Takaho Watanabe, Kazunari Kondo","doi":"10.3358/shokueishi.65.61","DOIUrl":"10.3358/shokueishi.65.61","url":null,"abstract":"<p><p>Since the establishment of procedures for the safety assessment of food products that use recombinant DNA technology, the manufacture, import, and sale of genetically modified (GM) foods that have not undergone safety assessment are prohibited under the Food Sanitation Act. Therefore, a performance study to confirm the GM food testing operations of each laboratory is very important to ensure the reliability of the GM food monitoring system. In 2022, GM papaya line PRSV-YK-which has not yet been authorized in Japan-was selected for testing, and a papaya paste and a DNA solution were used as the test samples. With these samples, a laboratory performance study of the DNA extraction and real-time PCR operations was conducted. This confirmed that the 18 participating laboratories were generally performing the DNA extraction and real-time PCR operations correctly. However, some laboratories using certain DNA amplification reagent with some real-time PCR instruments were not able to determine the PRSV-YK detection test. This suggests that the PRSV-YK detection test may not be able to correctly detect samples containing GM papaya when performed with these combinations of instruments and reagent. In order to ensure the reliability of the PRSV-YK detection test, it is necessary to examine in detail how the combination of DNA polymerase reagents and real-time PCR instruments affects the detection limit, and to implement an appropriate solution.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 3","pages":"61-66"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141735672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.3358/shokueishi.65.113
Hiroshi Fujikawa
The upper and lower limits of microbial colony count on agar plate are essential for microbial cell calculation of food samples. In the present study, the limits presented by the three standards of Ministry of Health, Labor, and Welfare of Japan, Food and Drug Administration of US (FDA), and Japanese Industrial Standards (JIS) were studied from the stochastic point of view. Here colony counts per plate were assumed to follow the Poisson distribution from our previous studies. The probability of acceptance of a pair of colony counts, PA for cell calculation by each standard was then calculated for various values of the mean of the Poisson distribution theoretically and by simulation with random sampling numbers. The values of PA at the lower and upper limits of the standards were low. For example, PA at the mean of 25 which is the lower limit of the FDA standard was 0.278. The values of PA of colony count pairs by the three standards were demonstrated in a wide range of the mean colony count. The largest range of the mean at PA>0.5 was observed in the JIS standard among the three. A new method to determine the limits for colony counts was developed with the risk of not acceptance. These findings would be helpful to consider the limits of colony counts for cell calculation.
{"title":"[Stochastic Considerations on the Upper and Lower Limits of Colony Counts on Agar Plate for Microbial Count Calculation].","authors":"Hiroshi Fujikawa","doi":"10.3358/shokueishi.65.113","DOIUrl":"https://doi.org/10.3358/shokueishi.65.113","url":null,"abstract":"<p><p>The upper and lower limits of microbial colony count on agar plate are essential for microbial cell calculation of food samples. In the present study, the limits presented by the three standards of Ministry of Health, Labor, and Welfare of Japan, Food and Drug Administration of US (FDA), and Japanese Industrial Standards (JIS) were studied from the stochastic point of view. Here colony counts per plate were assumed to follow the Poisson distribution from our previous studies. The probability of acceptance of a pair of colony counts, P<sub>A</sub> for cell calculation by each standard was then calculated for various values of the mean of the Poisson distribution theoretically and by simulation with random sampling numbers. The values of P<sub>A</sub> at the lower and upper limits of the standards were low. For example, P<sub>A</sub> at the mean of 25 which is the lower limit of the FDA standard was 0.278. The values of P<sub>A</sub> of colony count pairs by the three standards were demonstrated in a wide range of the mean colony count. The largest range of the mean at P<sub>A</sub>>0.5 was observed in the JIS standard among the three. A new method to determine the limits for colony counts was developed with the risk of not acceptance. These findings would be helpful to consider the limits of colony counts for cell calculation.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 5","pages":"113-117"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142856809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.3358/shokueishi.65.53
Hitoshi Miyazaki, Masaru Taniguchi
We have developed a rapid genus identification method for poisonous plants. The real-time PCR using the TaqMan® probe method was employed for detection, with the amplified targets being the "trnL (UAA)-intron" or "trnL-trnF intergenic spacer" regions of chloroplast DNA. The targeted plants were selected six genera (Aconitum, Colchicum, Veratrum, Brugmansia, Scopolia and Narcissus), which have been implicated in many instances of food poisoning in Japan. A tissue lysis solution was used for DNA extraction, which can be completed within approximate 30 min. A master mix corresponding to the tissue lysis solution was used for real-time PCR reagents. As a result, we were able to complete the entire process from DNA extraction to genus identification in 4 to 5 hr. The detection sensitivity was estimated at approximately 1 pg of DNA for all six plant genera. Remarkably, an amplification plot was discerned even with the crude cell lysates of all samples. It was also possible to obtain amplification curves for three plant samples that had been subjected to simulated cooking (boiling). This study suggests that the developed method can rapidly identify six genera of poisonous plants.
我们开发了一种快速鉴定有毒植物属种的方法。采用 TaqMan® 探针法进行实时 PCR 检测,扩增目标为叶绿体 DNA 的 "trnL (UAA)-intron" 或 "trnL-trnF 基因间距 "区域。目标植物选择了与日本多起食物中毒事件有关的六个属(Aconitum、Colchicum、Veratrum、Brugmansia、Scopolia 和 Narcissus)。DNA 提取采用组织裂解液,可在约 30 分钟内完成。与组织裂解液相对应的混合母液用于实时 PCR 试剂。因此,我们能够在 4 至 5 小时内完成从 DNA 提取到属种鉴定的整个过程。据估计,所有六个植物属的 DNA 检测灵敏度约为 1 pg。值得注意的是,即使是所有样本的粗细胞裂解液,也能发现扩增图。此外,经过模拟蒸煮(煮沸)的三个植物样本也能得到扩增曲线。这项研究表明,所开发的方法可以快速鉴定有毒植物的六个属。
{"title":"[Development of a Genus Identification Method for Poisonous Plants Using Real-Time PCR].","authors":"Hitoshi Miyazaki, Masaru Taniguchi","doi":"10.3358/shokueishi.65.53","DOIUrl":"https://doi.org/10.3358/shokueishi.65.53","url":null,"abstract":"<p><p>We have developed a rapid genus identification method for poisonous plants. The real-time PCR using the TaqMan<sup>®</sup> probe method was employed for detection, with the amplified targets being the \"trnL (UAA)-intron\" or \"trnL-trnF intergenic spacer\" regions of chloroplast DNA. The targeted plants were selected six genera (Aconitum, Colchicum, Veratrum, Brugmansia, Scopolia and Narcissus), which have been implicated in many instances of food poisoning in Japan. A tissue lysis solution was used for DNA extraction, which can be completed within approximate 30 min. A master mix corresponding to the tissue lysis solution was used for real-time PCR reagents. As a result, we were able to complete the entire process from DNA extraction to genus identification in 4 to 5 hr. The detection sensitivity was estimated at approximately 1 pg of DNA for all six plant genera. Remarkably, an amplification plot was discerned even with the crude cell lysates of all samples. It was also possible to obtain amplification curves for three plant samples that had been subjected to simulated cooking (boiling). This study suggests that the developed method can rapidly identify six genera of poisonous plants.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 3","pages":"53-60"},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141735670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present study verified that it is possible to analyze melengesterol acetate using the existing multi-residue method. Melengestrol acetate was extracted from livestock products using acidic acetonitrile acidified with acetic acid in the presence of n-hexane and anhydrous sodium sulfate. The crude extracts were cleaned up using an octadecylsilanized silica gel cartridge column. Separation by HPLC was performed using an octadecylsilanized silica gel column with linear gradient elution of 0.1 vol% formic acid and acetonitrile containing 0.1 vol% formic acid. For the determination of the analyte, tandem mass spectrometry with positive ion electrospray ionization was used. In recovery tests using four livestock products fortified with maximum residue limits levels of melengestrol acetate (0.001-0.02 mg/kg), the truenesses ranged from 82% to 100%, and the repeatabilities for the entire procedure ranged from 0.5 RSD% to 5.6 RSD%. In recovery tests using 11 livestock products fortified with 0.0005 mg/kg of melengestrol acetate, the truenesses ranged from 88% to 99%, and the repeatabilities ranged from 1.3 RSD% to 5.4 RSD%. The limit of quantification for melengestrol acetate in livestock products was 0.0005 mg/kg.
{"title":"[Analytical Method for Melengestrol Acetate in Livestock Products Using LC-MS/MS].","authors":"Takatoshi Sakai, Hiroyuki Kikuchi, Satoru Nemoto, Hiroshi Akiyama, Takaaki Taguchi, Tomoaki Tsutsumi","doi":"10.3358/shokueishi.65.15","DOIUrl":"10.3358/shokueishi.65.15","url":null,"abstract":"<p><p>The present study verified that it is possible to analyze melengesterol acetate using the existing multi-residue method. Melengestrol acetate was extracted from livestock products using acidic acetonitrile acidified with acetic acid in the presence of n-hexane and anhydrous sodium sulfate. The crude extracts were cleaned up using an octadecylsilanized silica gel cartridge column. Separation by HPLC was performed using an octadecylsilanized silica gel column with linear gradient elution of 0.1 vol% formic acid and acetonitrile containing 0.1 vol% formic acid. For the determination of the analyte, tandem mass spectrometry with positive ion electrospray ionization was used. In recovery tests using four livestock products fortified with maximum residue limits levels of melengestrol acetate (0.001-0.02 mg/kg), the truenesses ranged from 82% to 100%, and the repeatabilities for the entire procedure ranged from 0.5 RSD% to 5.6 RSD%. In recovery tests using 11 livestock products fortified with 0.0005 mg/kg of melengestrol acetate, the truenesses ranged from 88% to 99%, and the repeatabilities ranged from 1.3 RSD% to 5.4 RSD%. The limit of quantification for melengestrol acetate in livestock products was 0.0005 mg/kg.</p>","PeriodicalId":54373,"journal":{"name":"Food Hygiene and Safety Science","volume":"65 1","pages":"15-19"},"PeriodicalIF":0.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140023330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}