• Food Science of Animal Resources
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• v.36 no.2
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• pp.254-261
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• 2016

The purpose of this study was to analyze oxidized methionines in the myosin isoforms of porcine longissimus thoracis, psoas major, and semimembranosus muscles by liquid chromatography (LC) and mass spectrometry (MS). A total of 836 queries matched to four myosin isoforms (myosin-1, -2, -4, and -7) were analyzed and each myosin isoform was identified by its unique peptides (7.3-13.3). Forty-four peptides were observed from all three muscles. Seventeen peptides were unique to the myosin isoform and the others were common peptides expressed in two or more myosin isoforms. Five were identified as oxidized peptides with one or two methionine sulfoxides with 16 amu of mass modification. Methionines on residues 215 (215), 438 (438), 853 (851), 856 (854), 1071 (1069), and 1106 (1104) of myosin-1 (myosin-4) were oxidized by the addition of oxygen. Myosin-2 had two oxidized methionines on residues 215 and 438. No queries matched to myosin-7 were observed as oxidized peptides. LC-MS/MS allows analysis of the oxidation of specific amino acids on specific residue sites, as well as in specific proteins in the food system.

• Korean Journal of Medicinal Crop Science
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• v.13 no.6
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• pp.273-277
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• 2005

Adventitious shoots were directly induced from leaf explants of R. glutinosa, an important medicinal plant. Proliferating shoot cultures were obtained by culturing leaf discs on Murashige and Skoog(MS) medium alone or combination with auxins and cytokinins. MS medium supplemented with 1 $mg/{\ell}\;BA\;and\;2\;mg/{\ell}$ IAA was the most effective, providing high shoot bud formation frequency without formation of intervening callus. The effect of leaf age on adventitious shoot formation was also investigated. The maximum shoot bud production (93.4%) was achived using 3rd leaf from apex of 6 weeks old plantlets after seed germination. Plantlet were rooted on an half-strength MS (1/2MS) medium containing 0.1 $mg/{\ell}\;IBA$. This prtocol is useful for clonal propagation and Agrobacterium-mediated transforamtion in R. glutinosa.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.193-198
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• 2017

Scutellaria baicalensis, Eleutherococcus senticosus, and Angelica sinensis have been used as raw materials for health functional foods. This study was conducted to develop a novel method to analyze levels of baicalin (Scutellaria baicalensis), eleutheroside E (Eleutherococcus senticosus), and ligustilide (Angelica sinensis) simultaneously in health functional foods. The methanol extracted samples were analyzed and quantified via liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the positive ion mode and the negative ion mode using multiple reaction monitoring. Standard calibration curves confirmed linearity with the correlation coefficient ($r^2$) of > 0.99 at $100-2000{\mu}g/mL$ concentration range. The limits of detection (LODs) and limits of quantitation (LOQs) were in the range of $13.0{\sim}35.2{\mu}g/L$ and $39.3{\sim}106.7{\mu}g/L$, respectively. The recovery results ranged between 91.4~109.9% at 3 different concentration levels with relative standard deviations (RSDs) less than 5%. The proposed analytical method was characterized with high accuracy and acceptable precision. The new method would be an effective tool to analyze baicalin, eleutheroside E, and ligustilide simultaneously in raw materials of health functional foods.

• Analytical Science and Technology
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• v.24 no.4
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• pp.237-242
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• 2011

In this study, an analytical method was developed for residual metamizol in beef and pork using LC/MS/MS. 4-methylaminoantipyrin (MAA), the main metabolite of metamizol was targeted for analysis instead of its parent compound. MAA was simply extracted from meat by acetonitrile, purified and then analyzed by multiple reaction monitoring method (MRM). Standard addition method was used for calibration. The calibration curves showed the linearity of $r^2$ > 0.99 for both matrices included. The developed method was validated by six-time intra-lab tests and inter-lab tests with two other institutes. The validation of the whole procedure for beef showed the intra-lab accuracies of 78-102% (CV 5.5-9.1%) and the inter-lab accuracy of 98% (CV 14%); the intra-lab accuracies of 95-99% (CV 3.9-5.6%) and the inter-lab accuracy of 111% (CV 13%).

• Nutrition Research and Practice
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• v.6 no.1
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• pp.78-85
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• 2012

Whether the $FTO$ polymorphisms interact with environmental factors has not yet been evaluated in associations with metabolic syndrome (MS) risk. The present study investigated the association of the $FTO$ rs9939609 genotypes, body mass index (BMI), and lifestyle-related factors including smoking, alcohol drinking, physical activity, and diet with MS incidence. A population-based prospective cohort study comprised 3,504 male and female Koreans aged 40 to 69 years. At the beginning of the study, all individuals were free of MS and known cardiovascular disease. Incident cases of MS were identified by biennial health examinations during a follow-up period from April 17, 2003 to April 15, 2009. Pooled logistic regression analysis was applied to obtain relative odds (RO) of MS with its 95% confidence interval (CI). After controlling for potential MS risk factors, we observed no association between the rs9939609 genotypes and MS incidence. In analysis stratified by BMI, however, carriers with the $FTO$ risk allele whose BMI is $29kg/m^2$ or greater showed an approximately 6-fold higher RO (95% CI: 3.82 to 9.30) compared with non-carriers with BMI less than $25kg/m^2$. In particular, the association between the rs9939609 variants and MS risk was significantly modified by high BMI (P-value for interaction < 0.05). Such significant interaction appeared in associations with central obesity and high blood pressure among the MS components. Because carriers of the $FTO$ risk alleles who had BMI of $29kg/m^2$ or greater are considered a high risk population, we suggest that they may need intensive weight loss regimens to prevent MS development.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.277-290
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• 2012

The metabolic profiles of Panax quinquefolius and its associated therapeutic values are critically affected by the repetitious steaming times. The times-dependent steaming effect of P. quinquefolius is not well-characterized and there is also no official guideline on its times of steaming. In this paper, a UPLC-Q-TOF-MS/MS method was developed for the qualitative profiling of multi-parametric metabolic changes of raw P. quinquefolius during the repetitious steaming process. Our method was successful in discriminating the differentially multi-steamed herbs. Meantime, the repetitious steaming-inducing chemical transformations in the preparation of black American ginseng (American ginseng that was subjected to 9 cycles of steaming treatment) were evaluated by this UPLC-Q-TOF-MS/MS based chemical profiling method. Under the optimized UPLC-Q-TOF-MS/MS conditions, 29 major ginsenosides were unambiguously identified and/or tentatively assigned in both raw and multi-steamed P. quinquefolius within 19 min, among them 18 ginsenosides were detected to be newly generated during the preparatory process of black American ginseng. The mechanisms involved were further deduced to be hydrolysis, dehydration, decarboxylation and addition reactions of the original ginsenosides in raw P. quinquefolius through analyzing mimic 9 cycles of steaming extracts of 14 pure reference ginsenosides. Our novel steaming times-dependent metabolic profiling approach represents the paradigm shift in the global quality control of multi-steamed P. quinquefolius products.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.77-81
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• 1995

When cultured on MS medium supplemented with 0.5 mg/L NAA alone or 1.0 mg/L 2,4-D and 0.5 mg/L BA, immature zygotic embryos of Stewartia koreana formed embryogenic calli and somatic embryos. In investigate effect of sucrose concentration on somatic embryo development, embryogenic calli were transferred to MS basal medium containing 1.5,3, 6 or 9% sucrose. The greatest frequency of somatic embryos was obtained on medium containing 6% sucrose. However addition of 1.5 or 9% sucrose to medium inhibited somatic embryo germination and development into normal plantlet After 5 weeks of hardening culture on medium containing 6% sucrose, somatic embryos were transferred to half strangth MS medium supplemented with 0.1% charcol, wherein these embryo developed into the normal plantlets.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.149-154
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• 2000

Embryogenic suspension cultures were initiated using embryogenic callus from immature inflorescence explants (Aralia cordata Thunb.) cultured on solid MS medium containing 1 mg/L 2,4-D for 8 weeks and then the embryogenic callus was proliferated in liquid MS medium containing 1 mg/L 2,4-D. After sieving the suspensions (pore size 270$\mu$m), embryogenic cells were cultured in liquid MS medium with cytokinins (kinetin, BA, zeatin) for two weeks. When the embryogenic cells were transferred to liquid MS basal medium, primary somatic embryos were developed after 5 weeks of culture. Secondary embryos were developed directly from the primary torpedo and cotyledonary embryos cultured in solid MS basal medium. Frequency of secondary embryogenesis was higher on medium containing 2 mg/L kinetin than the other cytokinins. Plant regeneration was highly recorded by placing secondary cotyledonary embryos induced from primary cotyledonary embryos in MS medium containing 2 mg/L kinetin or 2 mg/L zeatin (25.4% and 28.6%, respectively). The plant regeneration from secordary embryos was prohibited by tertiary embryogenesis.

• Analytical Science and Technology
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• v.23 no.5
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• pp.457-464
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• 2010

The analytical method of four pharmaceuticals (virginiamycin, erythromycin, tylosin and cimetidine) in drinking water was developed. Effective simultaneous sample clean-up and extraction by solid-phase extraction (SPE) using HLB cartridge prior to LC/ESI-MS/MS analysis were performed. A linear correlation observed in the calibration curves for drinking water in the range of 0.01~2.0 ng/mL showed above $r^2$=0.995. Absolute recovery was in the range of 64.7~118.1% (except cimetidine (37.7~48.1%)). Limit of detection (LOD) and limit of quantitation (LOQ) in spiked drinking water matrix were in the range of 1.6~74.8 pg/mL and 5.5~249.7 pg/mL, respectively. The established method can be used to determine low pg/mL levels of pharmaceuticals in the drinking water.

• Journal of Life Science
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• v.21 no.3
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• pp.464-467
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• 2011

Quercetin is a major flavonoid present in onions, which acts as an antioxidant. Quercetin exists both as a free compound and conjugated with carbohydrates, primarily as glucosides in onion. Aged black onion was made through a 30 day aging process in which the onions were kept in an environment of $60^{\circ}C$ and high humidity (90% RH). Quercetin and quercetin glucosides were assayed in onion bulbs before and after the aging process, using high performance liquid chromatography-electrospray ion trap mass spectrometry (HPLC-ESI/MS/MS). Quercetin mono- and diglucosides were identified in fresh onion bulbs, whereas quercetin aglycone was the only form present in aged black onion bulbs. These findings indicate that the quercetin mono- and di-glucosides present in fresh onions undergo complete deglycosylation during the aging process. Such profiling will provide a rapid method that can be used to assess changes in the two major quercetin glycosides during the aging process of onion bulbs.