• Journal of Magnetics
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• v.21 no.1
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• pp.40-45
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• 2016

Nickel substituted nano-sized ferrite powders, $Co_{1-x}Ni_xFe_2O_4$, $Mn_{1-x}Ni_xFe_2O_4$ and $Mn_{1-2x}Zn_xNi_xFe_2O_4$ ($0.0{\leq}x{\leq}0.2$), were fabricated using a sol-gel method, and their crystallographic and magnetic properties were subsequently compared. The lattice constants decreased as quantity of nickel substitution increased, while the particle size decreased in $Co_{1-x}Ni_xFe_2O_4$ ferrite but increased for the $Mn_{1-x}Ni_xFe_2O_4$ and $Mn_{1-2x}Zn_xNi_xFe_2O_4$ ferrites. For the $Co_{1-x}Ni_xFe_2O_4$ and $Mn_{1-x}Ni_xFe_2O_4$ ($0.0{\leq}x{\leq}0.2$) ferrite powders, the $M{\ddot{o}}ssbauer$ spectra could be fitted as the superposition of two Zeeman sextets due to the tetrahedral and octahedral sites of the $Fe^{3+}$ ions. However, the $M{\ddot{o}}ssbauer$ spectrum of $Mn_{0.8}Zn_{0.1}Ni_{0.1}Fe_2O_4$ consisted of two Zeeman sextets and one single quadrupole doublet due to the ferrimagnetic and paramagnetic behavior. The area ratio of the $M{\ddot{o}}ssbauer$ spectra could be used to determine the cation distribution equation, and we also explain the variation in the $M{\ddot{o}}ssbauer$ parameters by using this cation distribution equation, the superexchange interaction and the particle size. The saturation magnetization decreased in the $Co_{1-x}Ni_xFe_2O_4$ and $Mn_{1-2x}Zn_xNi_xFe_2O_4$ ferrites but increased in the $Mn_{1-x}Ni_xFe_2O_4$ ferrite with nickel substitution. The coercivity decreased in the $Co_{1-x}Ni_xFe_2O_4$ and $Mn_{1-2x}Zn_xNi_xFe_2O_4$ ferrites but increased in the $Mn_{1-x}Ni_xFe_2O_4$ ferrite with nickel substitution. These variations could thus be explained by using the site distribution equations, particle sizes and spin magnetic moments of the substituted ions.

• Journal of Pharmaceutical Investigation
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• v.36 no.5
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• pp.343-348
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• 2006

The purpose of the present study was to evaluate the bioequivalence of two zolpidem tartrate tablets, Stilnox tablet(Sanofi-aventis Korea, reference product) and Zanilo tablet(ChoDang Pharm Co., Ltd., Korea, test product), according to the guidelines of Korea Food and Drug Administration(KFDA). After adding an internal standard(cimetropium), 250 ${\mu}L$ plasma samples were extracted using 1.3 mL of ethyl acetate. Extracted compounds were analyzed by HPLC with triple-quadrupole mass spectrometry. This method for determination of zolpidem is proved accurate and reproducible with the limit of quantitation of 1 ng/mL in human plasma. Twenty-four healthy male Korean volunteers received each medicine at the zolpidem tartrate dose of 10 mg in a $2{\times}2$ crossover study. There was one-week washout period between the doses. Plasma concentrations of zolpidem were monitored for over a period of 8 hr after the administration. $AUC_{0-t}$(the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$(maximum plasma drug concentration) and $T_{max}$(time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_{0-t}$ and $C_{max}$. No significant sequence effect was found for all of the bio-availability parameters indicating that the crossover design was properly performed. The 90% confidence intervals for the log transformed data were acceptable range of log 0.8 to log 1.25(e.g., log 0.92-log 1.06 for $AUC_{0-t}$, log 0.96-log 1.13 for $C_{max}$). The major parameters, $AUC_{0-t}$ and $C_{max}$ met the criteria of KFDA for bioequivalence indicating that Zanilo tablet is bioequivalent to Stilnox tablet.

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.323-330
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• 2016

Pinellia ternata Breitenbach, the natural medicinal plant of the Araceae family, is a perennial plant originated from the East Asia, but also widely distributed in Europe and North America. Its tuber is used as traditional medicine for treatment of various diseases such as vomiting, inflammation, and traumatic injury. Pharmacological studies revealed that P. ternata possesses anticonvulsant, anti-tumor, insecticidal, and cytotoxic activities. Despite being well-known as the useful medicinal plant, there is no reliable, standardized method for origin discrimination. Ultra performance liquid chromatography-photodiode array detector and quadrupole time of flight-mass spectrometry based metabolite-profiling was applied to explore significant metabolite for origin discrimination between Korean and Chinese P. ternata. One compound was isolated from Korean P. ternata using repeated ODS column chromatography by bioactivity guided fractionation, and determined as [6]-gingerol according to the results of spectroscopic data including nuclear magnetic resonance and MS. This compound was selected as cosmeceutical biomarker by fingerprints, and it was associated to melanin inhibitory effect determining its origin authenticity. Furthermore, the calibration curve of biomarker was prepared using validated method for the comparison of content between Korean and Chinese P. ternata. This is the report to address the selection and successful validation of the discriminant metabolite for confirmation of Korean P. ternata.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.487-495
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• 2017

Background: Although flowers of Panax ginseng Meyer (FPG), Panax quinquefolius L. (FPQ), and Panax notoginseng Burk. (FPN) have been historically used as both medicine and food, each is used differently in practice. Methods: To investigate the connection between components and enhancing immunity activity of FPG, FPQ, and FPN, a method based on a rapid LC coupled with quadrupole time-of-flight MS and immunomodulatory activity study evaluated by a carbon clearance test were combined. Results: According to quantitative results, the ratio of the total content of protopanaxatiol-type ginsenosides to protopanaxadiol-type ginsenosides in FPN was 0, but ranged from 1.10 to 1.32 and from 0.23 to 0.35 in FPG and FPQ, respectively. The ratio of the total content of neutral ginsenosides to the corresponding malonyl-ginsenosides in FPN ($5.52{\pm}1.33%$) was higher than FPG ($3.2{\pm}0.64%$) and FPQ ($2.39{\pm}0.57%$). The colorimetric analysis showed the content of total ginsenosides in FPQ, FPG, and FPN to be $13.75{\pm}0.60%$, $17.45{\pm}0.42%$, and $12.45{\pm}1.77%$, respectively. The carbon clearance assay indicated that the phagocytic activity of FPG and FPQ was higher than that of FPN. A clear discrimination among FPG, FPQ, and FPN was observed in the principal component analysis score plots. Seven compounds were confirmed to contribute strongly by loading plots, which may be the cause of differences in efficacy. Conclusion: This study provides basic information about the chemical and bioactive comparison of FPG, FPQ, and FPN, indicating that protopanaxtriol-type ginsenosides and malonyl-ginsenosides may play a key role in their enhancing immunity properties.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.14-14
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• 2018

This Camptotheca acuminata Decne. (CA), belonging to Nyssaceae, is a deciduous tree. and has been used as Traditional Chinese medicine since ancient times. The CA produces camptothecin a natural indole alkaloid, and reported to have anti-cancer effects. But the studies on biological activities of CA leaves are insufficient. Therefore, this study confirmed various biological activities such as antioxidant, antidiabetic, anticancer, antiinflammatory and metabolism analysis by HPLC-MS/MS of CA leaves. The $RC_{50}$ values of DPPH radical scavenging activity of ethyl acetate fraction, n-Butanol fraction, methanol extraction, water fraction and n-Hexane fraction were $12.23{\pm}0.01$, $15.93{\pm}0.42$, $55.12{\pm}0.45$, $56.29{\pm}4.15$ and $427.29{\pm}6.13ug/mL$, respectively. The $IC_{50}$ values of ${\alpha}$-glucosidase inhibitory activity of ethyl acetate fraction, n-Butanol fraction, methanol extraction, n-Hexane fraction and water fraction were $24.29{\pm}0.14$, $47.86{\pm}0.45$, $54.23{\pm}1.21$ $466.76{\pm}2.21$ and $623.91{\pm}9.67ug/mL$, respectively. The nitric oxide release activity of n-Hexane fraction, methanol extraction, ethyl acetate fraction, water fraction and n-Butanol fraction were $31.49{\pm}5.74$, $29.79{\pm}0.71$, $26.89{\pm}0.71$, $8.24{\pm}5.83$ and $7.75{\pm}4.08%$ at 25 ug/mL, respectively. The anti-cancer activity of n-Hexane fraction, methanol extraction, ethyl acetate fraction, water fraction and n-Butanol fraction were $31.49{\pm}5.74$, $29.79{\pm}0.71$, $26.89{\pm}0.71$, $8.24{\pm}5.83$ and $7.75{\pm}4.08%$ at 25 ug/mL, respectively. The ethyl acetate fraction activities showed higher biological activities than other fractions. Thus, Additional studies were conducted using ethyl acetate fraction. Metabolite analysis was performed using a LCMS-8040 triple quadrupole mass spectrometer. As a result, Five compounds (1-5) were identified in the ethyl acetate fraction of the CA leave. The identification of these compounds was generated by the analysis of fragmentation methods of the negative and positive ion modes. Five compounds were identified as gallic acid (1), chlorogenic acid (2), isoquercetin (3), astragalin (4) and camptothecin (5). These results suggest that the CA leave can be used for functional materials.

• Journal of Magnetics
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• v.15 no.4
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• pp.159-164
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• 2010

The Zn, Co and Ni substituted manganese ferrite powders, $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$, were fabricated by the solgel method, and their crystallographic and magnetic properties were studied. The Zn substituted manganese ferrite, $Zn_{0.2}Mn_{0.8}Fe_2O_4$, had a single spinel structure above $400^{\circ}C$, and the size of the particles of the ferrite powder increased when the annealing temperature was increased. Above $500^{\circ}C$, all the $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$ ferrite had a single spinel structure and the lattice constants decreased with an increasing substitution of Zn, Co, and Ni in $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$. The Mossbauer spectra of $Mn_{1-x}Zn_xFe_2O_4$ (0.0$\leq$x$\leq$0.4) could be fitted as the superposition of two Zeeman sextets due to the tetrahedral and octahedral sites of the $Fe^{3+}$ ions. For x = 0.6 and 0.8 they showed two Zeeman sextets and a single quadrupole doublet, which indicated they were ferrimagnetic and paramagnetic. And for x = 1.0 spectrum showed a doublet due to a paramagnetic phase. For the Co and Ni substituted manganese ferrite powders, all the Mossbauer spectra could be fitted as the superposition of two Zeeman sextets due to the tetrahedral and octahedral sites of the $Fe^{3+}$ ions. The variation of the Mossbauer parameters are also discussed with substituted Zn, Co and Ni ions. The increment of the saturation magnetization up to x = 0.6 in $Mn_{1-x}Co_xFe_2O_4$ could be qualitatively explained using the site distribution and the spin magnetic moment of substituted ions. The saturation magnetization and coercivity of the $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$ (x = 0.4) ferrite powders were also compared with pure $MnFe_2O_4$.

• Journal of the Korean Magnetics Society
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• v.18 no.1
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• pp.19-23
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• 2008

The mixed ferrite $V_xFe_{3-x}O_4$(x=0.0, 0.15, 0.5, 1.0) thin films were prepared by sol-gel method. Their crystallographic and magnetic hyperfine properties have been studied using X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and conversion electron $M\"{o}ssbauer$ spectroscopy(CEMS). The crystal structure is found to be cubic spinel throughout the series($x{\leq}1.0$), and the lattice parameter $a_0$ increases linearly with increasing V content. XRD, XSP and CEMS indicate that $V^{3+}$ substitution for $Fe^{3+}$ in B-site is superior to $V^{2+}$ substitution for $Fe^{2+}$ in B-site. It is noticeable that both quadrupole shift and hyperfine field decreases with increasing V composition, suggesting the change of local symmetry and accompanying line-broadening. The line-broadening on CEMS spectra can be explained by the distribution of magnetic hyperfine fields.

• Food Science and Preservation
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• v.23 no.7
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• pp.1004-1011
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• 2016

Flavonoids, non-nutrient secondary metabolites of plants, are widely distributed in commonly consumed agro-food resources. Flavonoids include aglycones, and their glycosides are reported to have potential health-promoting compounds. The aim of this study was to investigate flavonoid glycosides in the fruit and leaves of Zizyphus jujuba var. inermis (Bunge) Rehder (jujube). A total of six flavonoids (five flavonols and one chalcone) were identified in jujube fruit and leaves by using ultra-performance liquid chromatography-diode array detector-quadrupole time of flight mass spectrometry along with chemical library and an internal standard. In positive ion mode, six flavonoids were linked to the C- and O-glycosides which were conjugated with sugar moieties based on kaempferol, quercetin, and phloretin aglycones. Total flavonoid contents of leaves (8,356.5 mg/100 g dry weight (DW)) was approximately 900-fold higher than that of fruit (fresh fruit, 13.6 mg/100 g dry DW; sun-dried fruits, 9.2 mg/100 g dry DW). Quercetin 3-O-rutinoside (rutin) and quercetin 3-O-robinobioside were the predominant flavonols in fruit and leaves of jujube. In particular, rutin had the highest content (6,735.2 mg/100 g DW) in leaves, and rutin is a widely reported bioactive compound. Phloretin 3',5'-di-C-glucoside (chalcone type) was detected only in leaves. The leaves of jujube contain a high content of flavonoids and the results of this study indicate that jujube leaves may be a source of bioactive flavonoids.

• Journal of Environmental Health Sciences
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• v.34 no.4
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• pp.271-278
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• 2008

Dialkylated phthalates have been commonly used as plasticizers and a variety of applications. Phthalate diesters have been shown to be developmental and reproductive toxicants. It is very difficult to exactly estimate the dose of dialkylated phthalates taken up by the general population because of environmental contamination. Urinary metabolites of phthalates enabled to estimate internal exposure. The objective of this study was quantitative determination of phthalate metabolites by LC/MS/MS with on-line cleanup method to analyze phthalate metabolites in Korean children's urine. We employed LC/MS/MS with on-line enrichment and column-switching techniques for this biological monitoring. Metabolites determined were 4 primary metabolites; MEHP, MnBP, MiBP, MEP and 2 secondary metabolites of DEHP; 5-OH-MEHP), 5-oxo-MEHP. We analyzed children's urine from 30 boys and 30 girls. The method detection limit of phthalate metabolites were 0.03 ng/mL for MEP, 1.05 ng/mL for MBP, 0.22 ng/mL for MEHP, 0.15 ng/mL for 5-OHMEHP and 0.16 ng/mL for 5-oxo-MEHP, respectively. Switching Column LC/MS/MS was proven to be a useful tool to determine metabolites of phthalate diesters in human urine. The correlation among phthalate metabolites was very high and statistically significant, except MEP. The children's age (months) was negatively correlated to the concentration of phthalate metabolites. The geometric mean concentration of phthalate metabolites (mg/g creatinine) in children's urine were 25.5 for MEP, 130.3 for MnBP, 56.8 for MiBP, 19.5 for MEHP, 85.6 for 5-OH-MEHP and 83.1 for 5-oxo-MEHP, respectively. Levels of estimated daily intake of parent phthalate compounds (${\mu}g$/kg bw/day) were 0.8 for DEP, 5.0 for DnBP, 1.9 for DiBP and $8.9{\sim}14.2$ for DEHP, respectively. Estimated daily intake for DEP and DiBP were lower than those of other studies but the value for DEHP was higher than that of other study.

• Analytical Science and Technology
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• v.28 no.4
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• pp.278-287
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• 2015

Phosphodiesterase type 5 inhibitors (PDE-5 inhibitors) are used in the treatment of erectile dysfunction. In recent years, a number of reports have been conducted on dietary supplements contaminated with PDE-5 analogues. In this study, 58 analogues of PDE-5 inhibitors were sorted into five groups: tadalafil, sildenafil, hongdenafil, vardenafil, and other analogues. These analogues were then evaluated using a liquid chromatography-quadrupole-time of flight mass spectrometry (LC-QTOF-MS) electrospray ionization mass method. Each compound has a unique fragmentation ion, which can be easily analyzed qualitatively. The fragmentation pathways of the analogues were elucidated based on the QTOF-MS and MS/MS data. Common ions were confirmed for each group by analyzing the structural characteristics and fragmentation pathways. Specifically, common ions were observed at m/z 169.08 and 135.04 (tadalafil analogues), m/z 311.15 and 283.12 (sildenafil analogues and hongdenafil analogues), and m/z 312.16 and 151.09 (vardenafil analogues). The advantage of this method is that the structure of unknown components can be determined by interpreting the product ions. Hence, the developed method can be used for the identification of unknown compounds. Fragmentation pathways may also aid in the detection and identification of PDE-5 inhibitor analogues.