• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.159-160
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• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.5
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• pp.129-139
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• 2012

Given digraph network $D=(N,A),n{\in}N,a=c(u,v){\in}A$ with source s and sink t, the maximum flow from s to t is determined by cut (S, T) that splits N to $s{\in}S$ and $t{\in}T$ disjoint sets with minimum cut value. The Ford-Fulkerson (F-F) algorithm with time complexity $O(NA^2)$ has been well known to this problem. The F-F algorithm finds all possible augmenting paths from s to t with residual capacity arcs and determines bottleneck arc that has a minimum residual capacity among the paths. After completion of algorithm, you should be determine the minimum cut by combination of bottleneck arcs. This paper suggests maximum adjacency merging and compute cut value method is called by MA-merging algorithm. We start the initial value to S={s}, T={t}, Then we select the maximum capacity $_{max}c(u,v)$ in the graph and merge to adjacent set S or T. Finally, we compute cut value of S or T. This algorithm runs n-1 times. We experiment Ford-Fulkerson and MA-merging algorithm for various 8 digraph. As a results, MA-merging algorithm can be finds minimum cut during the n-1 running times with time complexity O(N).

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.12
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• pp.726-734
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• 2004

This paper presents a facial animation method that enables the user to select a sequence of facial frames from the facial expression space, whose level of details the user can select hierarchically Our system creates the facial expression space from about 2400 captured facial frames. To represent the state of each expression, we use the distance matrix that represents the distance between pairs of feature points on the face. The shortest trajectories are found by dynamic programming. The space of facial expressions is multidimensional. To navigate this space, we visualize the space of expressions in 2D space by using the multidimensional scaling(MDS). But because there are too many facial expressions to select from, the user faces difficulty in navigating the space. So, we visualize the space hierarchically. To partition the space into a hierarchy of subspaces, we use fuzzy clustering. In the beginning, the system creates about 10 clusters from the space of 2400 facial expressions. Every tine the level increases, the system doubles the number of clusters. The cluster centers are displayed on 2D screen and are used as candidate key frames for key frame animation. The user selects new key frames along the navigation path of the previous level. At the maximum level, the user completes key frame specification. We let animators use the system to create example animations, and evaluate the system based on the results.

• Journal of Pharmaceutical Investigation
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• v.26 no.2
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• pp.71-82
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• 1996

This study has been undertaken to evaluate hydrophobic cyclodextrin(CD) derivatives as a sustained release carrier of azidothymidine(AZT), AZT, which has potent activity against AIDS and AIDS-related complex as thymidine analogue, has been reported that it has significant toxicity and short half life. Therefore, it is necessary to design sustained release oral dosage form to avoid undesirable side effects attributable to an excessive plasma concentration and to reduce the frequency of administration of AZT. Inclusion complexes of AZT with $acetyl-{\beta}-cyclodextrin\;(AC{\beta}CD)$ and $triacetyl-{\beta}-cyclodextrin(TA{\beta}CD)$ were prepared by solvent evaporation method. Interactions of AZT with CD were investigated by Differential Scanning Calorimetry(DSC) and Infrared Spectrophotometry(IR). The decreasing order of water solubilities of AZT and AZT-CD inclusion complexes were as follows; $AZT\;(27.873{\pm}0.015,mg/ml)\;>\;AZT-AC{\beta}CD\;(3.377{\pm}0.003)\;>\;AZT-TA{\beta}CD\;(2.528{\pm}0.001)$. Partition coefficients of $AZT-AC{\beta}CD\;and;\AZT-TA{\beta}CD$ inclusion complexes were increased by 1.27-fold, 1.54-fold in pH 1.2 and 1.32-fold, 1.47-fold in pH 6.8 in comparison with that of AZT. The mean dissolution time (MDT, min) which represents the rapidity of dissolution rate of AZT, $AZT-AC{\beta}CD,\;AZT-TA{\beta}CD$ were 5.12, 14.02 and 19.38 min in pH 1.2 and 2.52, 15.19 and 18.19 min in pH 6.8. AZT was very rapidly and completely dissolved in pH 1.2 and pH 6.8 within 5 minutes. But AZT-CD inclusion complexes showed the sustained release pattern in comparison with AZT alone. The simultaneous in situ nasal and jejunal recirculation study to compare the intrinsic absorptivity and the property of absorption sites revealed that the absorption of $AZT-TA{\beta}CD\;(N:35.35{\pm}1.08%,\;J:27.47{\pm}1.18%)$ was more than that of $AZT\;(N:16.89{\pm}2.25%,\;J:15.86{\pm}2.33%)$. The above results suggest that $TA{\beta}CD$ which is a hydrophobic cyclodextrin may serve as sustained release carrier with absorption enhancing effect.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.214-223
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• 2013

BACKGROUND: This study focused on the development of an analytical method about dichlorprop (DCPP; 2-(2,4-dichlorophenoxy)propionic acid) which is a plant growth regulator, a synthetic auxin for agricultural commodities. DCPP prevents falling of fruits during their growth periods. However, the overdose of DCPP caused the unwanted maturing time and reduce the safe storage period. If we take fruits with exceeding maximum residue limits, it could be harmful. Therefore, this study presented the analytical method of DCPP in agricultural commodities for the nation-wide pesticide residues monitoring program of the Ministry of Food and Drug Safety. METHODS AND RESULTS: We adopted the analytical method for DCPP in agricultural commodities by gas chromatograph in cooperated with Electron Capture Detector(ECD). Sample extraction and purification by ion-associated partition method were applied, then quantitation was done by GC/ECD with DB-17, a moderate polarity column under the temperature-rising condition with nitrogen as a carrier gas and split-less mode. Standard calibration curve presented linearity with the correlation coefficient ($r^2$) > 0.9998, analysed from 0.1 to 2.0 mg/L concentration. Limit of quantitation in agricultural commodities represents 0.05 mg/kg, and average recoveries ranged from 78.8 to 102.2%. The repeatability of measurements expressed as coefficient of variation (CV %) was less than 9.5% in 0.05, 0.10, and 0.50 mg/kg. CONCLUSION(S): Our newly improved analytical method for DCPP residues in agricultural commodities was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• Applied Biological Chemistry
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• v.9
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• pp.9-27
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• 1968

Studies were carried out in order to elucidate chemical components and microflora in three types of soy-sauce, 12-year aged soy-sauce prepared by improved method. 7-year aged and 20-year aged soy-sauce prepared by ordinary method. They results are summarized as follows: 1. The followings are found to be the important factors affecting the quality of soy sauce. a. Organic acids, reducing sugars and free amino acids were increased in the course of storage. b. In the aged soy-sauces under study non-volatile organic acid increased while volatile organic acid decreased and the total acidity was dependent only upon tie latter. c. It was found that suit concentration decreased during the storage. 2. The results of investigation of microflora in the stored soy-sauce are shown as follows. Soy-sauce Improved Ordinary Microbe 12-Y. 20-Y. 7-Y. Aerobic bacteria colony/1ml. 6 123 2 Halophilic lactic acid bacteria colony/1ml. 4 6 10 Osmophilic yeast colony/1ml. $828{\times}10^4$ 248 - b. In the stored soy-sauces, aerobic bacteria are incapable of growing due to drop in pH value and the influence of salt concentration. c. Halophilic lactic acid bacteria are incapable of growing due to drop in pH value, even the salt concentrations decreased during the storage. d. Osmophilic yeast are still growing in low pH value and in the decreasing salt concentration during the strage. 3. The results of amino acid analysis by paper partition chromatographic and calorimetric methods are shown as follows. a. Fourteen kinds of amino acid and thirteen amino acids were detected in the soy-sauce of 12-year aged improved soy-sauce and 7-year aged and 20-year aged ordinary one, respectively. b. The contents of aspartic acid, glutamic acid, serine, valine, leucine, lysine, histidine and methionine increased in the 20-year aged ordinary soy-sauce compared to the 7-year aged one. On the other hand those of alanine, tyrosine, phenylalanine and cystine decreased. 4. The results of sugar analysis by paper chromatography are as follows. a. In the 12-year aged improved soy-sauce, galactose, glucose, arabinose, xylose, rhamnose, maltose and an unknown were detected, and their amounts were in the above order except maltose and an unknown. b. Both in the 7 and 12-year aged ordinary soy-sauces, galactose, arabinose, xylose, glucose and rhamnose were detected and the amounts of the sugars were in the above order. c. In the non-aged ordinary soy-sauce, glucose was not detected but detected from 7-year and 20-year aged ordinary soy-sauce. 5. The results of organic acid analysis by paper chromatography were as follows. a. As volatile acids, acetic, propionic and butyric acids were detected in the 7-year aged ordinary soy-sauce. On the other hand in both the 20-year aged ordinary soy-sauce and the 12-year aged improved ones, only acetic acid was abundant while propionic and butyric acids were round in trace. It was found that propionic and butyric acids, as the unpleasant flavor components, decreased during the storage. b. In the ordinary soy-sauce, citric acid were produced during the storage and lack, malic and tartaric acids increased in the course of aging while succinic, glycolic, fumaric and malonic acids were shown to decrease. Glutaric and oxalic acids disappeared. Citric acid was produced also in the improved soy-sauce, but lactic, tartaric, succinic, malic, and glycolic acids decreased, while both malonic and glutaric acids disappeared. From the above results the citric acid production was considered to be a favorable factor for the taste. c. In the aged soy-sauces, pyruvic, α-ketoglutaric and probably acetoacetic and oxaloacetic acids (both in trace) were present and their amounts were in the above order. All of the α-keto acid abruptly decreased during the storage.