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Analytical Determination of Vitamin B12 Content in Infant and Toddler Milk Formulas by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

  • Lee, Jung-Hoon;Shin, Jin-Ho;Park, Jung-Min;Kim, Ha-Jung;Ahn, Jang-Hyuk;Kwak, Byung-Man;Kim, Jin-Man
    • Food Science of Animal Resources
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    • v.35 no.6
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    • pp.765-771
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    • 2015
  • The development of a sample preparation method and optimization of the analytical instrumentation conditions were performed for the determination of the vitamin B12 content in emulsified baby foods sold on the Korea market. After removal of the milk protein and fats by chloroform extraction and centrifugation, the vitamin B12 was water extracted from the sample. Following filtration of the solution through a nylon filter, the water-soluble extract was purified by solid-phase extraction using a Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). The solution eluted from the cartridge was dried under a stream of nitrogen gas and reconstituted with 1 mL of water. The sample solution was injected into an LC-MS/MS system after optimizing the mobile phase for vitamin B12 detection. The calibration curve showed good linearity with the coefficient of correlation (r2) value of 0.9999. The limit of detection was 0.03 µg/L and the limit of quantitation was 0.1 µg/L. The method of detection limit was 0.02 µg/kg. The vitamin B12 recovery from a spiking test was 99.62% for infant formula and 99.46% for cereal-based baby food. The sample preparation method developed in this study would be appropriate for the rapid determination of the vitamin B12 content in infant formula and baby foods with emulsified milk characteristics. The ability to obtain stable results more quickly and efficiently would also allow governments to exercise a more extensive quality control inspection and monitoring of products expected to contain vitamin B12. This method could be implemented in laboratories that require time and labor saving.

Therapeutic Effect of Hovenia dulcis Thunberg Extracts and 6 Types Herbal Extracts on $CCl_4-induced$ Chronic Organ Damages in the Rats-Liver and Kidney (Carbon Tetrachlorid으로 유발된 Rat의 만성 장기(간, 신장) 손상시 헛개나무열매 추출물등 6종 생약의 투여시 조직병리학적변화)

  • Lim, Mee-Kyoung;Kim, Joo-Wan;Kim, Hong-Tae;Lee, Byoung-Je;Ku, Sae-Kwang;Kang, Mi-Young;Lee, Keun-Woo
    • Journal of Veterinary Clinics
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    • v.24 no.3
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    • pp.384-391
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    • 2007
  • This study was conducted to clarify the effects of the Korean raisin (Hovenia dulcis Thunb) extracts and polyherbal extracts consisted of 6 types herbal extracts including HDT (HDTmix) on $CCl_4$ induced organ damages. Extracts were prepared by autoclave ($121^{\circ}C$, 15 psi, 3 hours) and filtered with nylon cloth and filter paper then freezing dried. Male Sprague-Dawley rats $(200^{\circ}{\ae}20g)$ were used as experimental groups, which were divided into 5 groups; intact control group (100 mg/kg), $CCl_4$ dosing group (100 mg/kg), $CCl_4$ dosing after HDT extract dosing group (100 mg/kg), $CCl_4$ dosing after HDTmix dosing group (100 mg/kg), Silymarin dosing group (5 mg/kg) after all test articles were orally dosed once a day for 28 days. They were sacrifiled under ether anesthesia. HDT extracts and HDTmix dramatically inhibits the $CCl_4$ intoxicated hepato/nephropathies with immuno-suppress changes on the spleen. They showed more dramatical protective effects on most of specific organs compared to that of Silymarin 5 mg/kg except for hepatoprotective effects in which, quite similar effects were detected. In addition, HDT extracts showed synergic effects with other types of herbal extracts because HDTmix showed more favorable protective effects on the all specific organs showing $CCl_4-related$ histopathological changes compared to HDT extracts.

Study for Residue Analysis of Herbicide, Clopyralid in Foods (식품 중 제초제 클로피랄리드(Clopyralid)의 잔류 분석법)

  • Kim, Ji-young;Choi, Yoon Ju;Kim, Jong Su;Kim, Do Hoon;Do, Jung Ah;Jung, Yong Hyun;Lee, Kang Bong;Kim, Hyo Chin
    • Korean Journal of Environmental Agriculture
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    • v.37 no.4
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    • pp.283-290
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    • 2018
  • BACKGROUND: Pesticide residue analysis is an essential activity in order to establish the food safety of agricultural products. Analytical approaches to the food safety are required to meet internationally the guideline of Codex (Codex Alimentarius Commission, CAC/GL 40). In this study, we developed a liquid chromatograph-tandem mass spectrometer (LC-MS/MS) method to determine the herbicide clopyralid in food matrixes. METHODS AND RESULTS: Clopyralid was extracted with aqueous acetonitrile containing formic acid and the extracts were mixed in a citrate buffer consisted of magnesium sulfate anhydrous, NaCl, sodium citrate dihydrate and disodium hydrogencitrate sesquihydrate followed by centrifugation. The supernatants were filtered through a nylon membrane filter and used for the analysis of clopyralid. The method was validated by accuracy and precision experiments on the samples fortified at 3 different levels of clopyralid. LC-MS/MS in positive mode was employed to quantitatively determine clopyralid in the food samples. Matrix-matched calibration curves were inearranged from 0.001 to 0.25 mg/kg with r2 > 0.994. The limits of detection and quantification were determined to be 0.001 and 0.01 mg/kg, respectively. There covery values of clopyralid for tified at 0.01 mg/kg in the control samples ranged from approximately 82 to 106% with relative standard deviations below 2 0%. CONCLUSION: The method developed in this study meets successfully the Codex guideline for pesticide residue analysis in food samples. This, the method could be applicable to determine pesticides in foods produced domestically and internationally.