In the general test section of Japan’s Specifications and Standards for Food Additives (9th edition), the chloride limit test, a visual inspection method, is “designed to demonstrate that the content of chloride in an additive does not exceed the acceptable limit specified in the individual monograph.” Because the chloride limit test is a visual inspection test, it determines the concentration of chloride that can be distinguished visually. The visual inspection method, on the other hand, makes it challenging to distinguish small differences in chloride concentration. The visual inspection method could not distinguish between adjacent chloride standard solutions unless there was a significant difference in concentration of more than 0.1 µg/mL for 0–0.5 µg/mL chloride standard solutions, more than 0.5 µg/mL for 0.5–1 µg/mL of chloride, and more than 1 µg/mL for 1–4 µg/mL chloride standard solutions. As a result, we examined the use of a UV-visible spectrophotometer to measure the absorbance of silver chloride (UV-Vis method). After the absorbance stabilized, a UV-Vis spectrophotometer was used to measure the absorbance at 600 nm after adding silver nitrate solution to either the test or chloride standard solution (approximately one hour). The calibration curve was linear (R2> 0.99) for concentrations ranging from 0.05 to 5 µg/mL, which are difficult to distinguish visually. By spiking samples with chloride equivalent to the criteria for three sample types: glycine, sodium dihydrogen phosphate, and sodium sulfate, this method was validated. After that, the chloride was quantified using the UV-Vis method. The UV-Vis method’s accuracy and precision were comparable to that of ion chromatography for the direct detection of chloride ions, with satisfactory accuracy (≥ 92.6%), precision (≤ 3.7%) and intra-laboratory reproducibility (≤ 7.3%). These results indicate that the UV-Vis method can discriminate against small differences in chloride concentrations that are difficult to determine using visual inspection methods. As a result of this study, it was demonstrated that the UV-Vis method is a simple and effective method for accurately determining chloride concentrations in test solutions

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Neonicotinoids are potent agonists of nicotine acetylcholine receptors and exert insecticidal effects by causing abnormal excitation of the nervous system. Recently, their effects on mammals, including humans, have become of concern. In the present study, we evaluated the effects of chronic exposure to two neonicotinoids, imidacloprid (IMI) and dinotefuran (DINO), using Caenorhabditis elegans as the model organism. We used 1, 10, 100, and 1000 µM solutions of nicotine, IMI, and DINO dissolved in 1% DMSO. Bioassays (growth, maturation, and reproduction tests) were performed on the L1-L2 larvae of wild-type C. elegans. To evaluate the effect of exposure over multiple generations and the correlation between concentrations and generations, the same study was conducted in second and third generations of the exposed group. The bioassay results showed concentration-dependent adverse effects at concentrations above 10 μM for both IMI and DINO in both tests for one generation. In the multi-generation study, the effect intensified with the progression of generations, and the toxicity of both IMI and DINO was cumulative. This effect was more pronounced in the breeding study, with significant adverse effects comparable to those of nicotine between generations at concentrations ≥1 μM. This study showed that neonicotinoid concentrations within crop residue limits can adversely affect ecosystem organisms. We suggest that chronic exposure to neonicotinoids may have adverse effects across generations, particularly on reproductive performance. These findings suggest the need to conduct a comprehensive toxicity assessment, including genetic analysis, such as RNA sequencing and real-time PCR, in the future

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Anti-food-terrorism measures are critical for identifying toxic substances and rescuing victims of food terrorism. A rapid analytical method based on liquid chromatography–tandem mass spectrometry (LC–MS/MS) was examined to quantify 17 carbamate pesticides in human blood or urine samples. Blood or urine samples were extracted using methanol or acetone and subjected to reversed-phase LC–MS/MS. Sample preparation and LC–MS/MS analysis required approximately 25 and 20 min, respectively. The recoveries of 16 carbamates from blood and urine samples spiked with 50 ng/mL of each pesticide ranged between 13.4% and 164.1% (92.1% and 200.0%) and between 39.0% and 119.5% (36.4% and 112.1%), respectively, when methanol and acetone were used as extractants. Thiodicarb could not be recovered from the blood samples, suggesting that it was enzymatically converted into methomyl. The analytical method used in this study is simple and useful; therefore, it can be used by public health institutions as an anti-food-terrorism measure.

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Generally, in Hiroshima Prefecture, Japan, the cultivation of the Pacific oyster Crassostrea gigas involves a process called “hardening” in which the oysters are intermittently left under anaerobic conditions by hanging them on racks in the intertidal zone for several months before the primary suspension of the oysters from offshore rafts. We investigated the effects of intermittent anaerobic loading on oysters, mainly for taste, using triploid Pacific oysters in summer and normal diploid oysters in winter. High performance liquid chromatography (HPLC) was used to quantify free amino acids and ATP-related compounds, and spectroscopic analysis was used to measure the amount of glycogen, which is an energy source for oysters and indicates their nutritional condition. In addition, sensory evaluations were conducted by the panels. In the summer experiment, the levels of several free amino acids, mainly related to sweetness, and the umami taste in the sensory evaluation were significantly higher, whereas the amount of glycogen did not change in the hardened group compared to the control group. In contrast, in the winter experiment, the levels of many free amino acids decreased in the hardened group compared to those in the control group. At the same time, glycogen levels and soft tissue weight also decreased. These results showed that the rearing environments of the hardened and control groups may have differed significantly between summer and winter. However, this study suggests that providing the oysters with intermittent anaerobic conditions just before harvest in summer may improve the taste.

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Greater celandine and Coleus forskohlii are designated as ingredients that require special attention (designated ingredients) under the Food Hygiene Act. In this study, we developed a method for the simultaneous quantitative analysis of coptisine and forskolin in dietary supplements containing the designated ingredients using ultra-high performance liquid chromatography (UHPLC). We also developed a simultaneous qualitative analysis method for coptisine, sanguinarine, forskolin, and isoforskolin in dietary supplements containing the designated ingredients using a UHPLC-quadrupole-Kingdon trap mass spectrometry with photodiode array detector. Extraction of samples was carried out by ultrasonication using methanol as the extraction solvent. An ODS column was used for quantitative and qualitative analyses. Quantitative analysis was performed on a gradient of 10 mmol/L phosphate buffer (pH 3.0)-acetonitrile, and qualitative analysis was performed on a gradient of 10 mmol/L ammonium formate buffer (pH 3.0)-acetonitrile. The recovery test results showed recoveries of between 97.23 and 102.14%; the standard deviation was within 2%, indicating good precision. In the application of our quantitative analysis method to commercial dietary supplements, maximums of 10.71 mg/bottle of coptisine and 27.73 mg/tablet of forskolin were detected. When a product containing 27.73 mg/tablet of forskolin was consumed as indicated on the label, the daily intake of forskolin was 110.92 mg. In the qualitative analysis, we confirmed the presence of coptisine, sanguinarine and forskolin in the dietary supplements. The isoforskolin content was confirmed except for one product that contained the minimum amount of forskolin.

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Aggrecan, which is a chondroitin sulfate proteoglycan (CSPG), has been considered as a superior functional nutraceutical for the treatment of joint diseases and other immune system diseases when compared to chondroitin sulfate (CS). The industrial production of CSPG generally employs salmon nasal cartilage, and the quality control of CSPG is required to meet the regulations for nutraceutical products prepared from natural resources. Although there are several commercially available nutraceuticals that contain CSPG as a major component, the quality and quantity of CSPG in each supplement are not guaranteed. This paper presents a simple, rapid, and reliable analytical approach for the quality control of CSPG during production, where electrophoresis, gel filtration HPLC, and CS unsaturated disaccharide analysis with CS degradation enzymes were employed. Finally, the quality of CSPG obtained from different extraction and purification processes were confirmed using these newly developed analytical procedures.

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Caffeine is one of the food components found in coffee beans, tea leaves including yerba mate, and cocoa. In recent years, due in part to the widespread use of energy drinks, the number of opportunities for young people to consume caffeine-containing foods and beverages has increased dramatically. On the other hand, health problems caused by excessive caffeine intake have been discussed. In order to clarify the problem of caffeine intake, this study investigated the perception of health risks of caffeine-containing beverages among university students and their actual consumption in daily life. Although university students consume caffeine-containing beverages on a daily basis, their awareness of caffeine and their awareness of the need for caution when consuming caffeine were considered to be low. The survey on beverage consumption showed that a certain number of university students have problems with the way and amount of caffeine-containing beverages they consume. There is a great possibility that the amount of caffeine intake from beverages will continue to increase in the future, including the expansion of the energy drink market. It is a challenge to disseminate information about the health risks of caffeine in the future. In addition, it is necessary to educate university students about caffeine addiction and to prevent drug abuse by providing them with information and knowledge about caffeine-containing foods.

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This study aimed to develop a preparation method for apramycin residue in livestock products for liquid chromatography–tandem mass spectrometry (LC-MS/MS). Apramycin was extracted from samples via alkaline hydrolysis or with trichloroacetic acid (TCA) in the presence of n-hexane (hexane). Next, matrix components were removed from the extracted apramycin using two types of hydrophilic-lipophilic balanced (HLB) solid-phase extraction (SPE) cartridges, and apramycin was retained with strong cation-exchange SPE cartridges. Apramycin recovery from the extract was evaluated using bovine muscle, liver, and fat samples with apramycin at the maximum residue limit-value (muscle and fat: 0.5 ppm, liver: 5 ppm). The recovery rate of alkaline hydrolysis extraction was 75.5-90.1% and hexane-TCA extraction was 77.3-92.6%, demonstrating that this method could sufficiently remove matrix components that would affect the measurement, as indicated by guidelines of the Ministry of Health, Labor and Welfare. The method examined in this study is effective for apramycin residue sample preparation in livestock products for quantitative LC-MS/MS measurements.

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