• Journal of Integrative Natural Science
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• v.4 no.2
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• pp.91-98
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• 2011

Quantitative structure-activity relationships (QSAR) have been applied for two decades in the development of relationships between physicochemical properties of chemical substances and their biological activities to obtain a reliable statistical model for prediction of the activities of new chemical entities. The fundamental principle underlying the QSAR is that the structural difference is responsible for the variations in biological activities of the compounds. In this work, we developed 3D-QSAR model for a series of 5-Lipoxygenase inhibitors, utilizing comparative molecular field analysis (CoMFA) and Topomer CoMFA methodologies. Our developed models addressed superiority of Topomer CoMFA over CoMFA. The CoMFA model was obtained with $q^2$=0.593, $r^2$=0.939, $Q^2$=0.334 with 6 optimum number of components (ONC). Higher statistical results were obtained with the Topomer CoMFA model ($q^2$=0.819, $r^2$=0.947, ONC=5). Further robustness of developed models was checked with the ANOVA test and it shows F=113 for CoMFA and F=162.4 for Topomer CoMFA model. Contour map analysis indicated that the more requirement of electrostatic parameter for improved potency.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.77-83
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• 2008

Radial and axial variations of microfibril angle (MFA) within stems of three commercial softwoods (Pinus densiflora, Pinus koraiensis and Pinus rigida) grown in Korea were examined by iodine crystal deposition method. The average MFA were $16.4^{\circ}$ in Pinus densiflora, 14.4, in Pinus koraiensis, and $26.2^{\circ}$ in Pinus rigida, respectively. The MFA in earlywood and latewood decreased with age to about 15~20 years, and then remained almost constant. The MFA of latewood was slightly smaller than that of earlywood. The MFA in the three species was a little smaller at the base of stem and decreased slightly with increasing tree height, but no significant difference by height was identified only in earlywood of Pinus rigida. Consequently, it was considered that the MFA could be an useful index for identifying juvenile wood and adult wood of Pinus densiflora, Pinus. koraiensis and Pinus rigida.

• Journal of Environmental Policy
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• v.5 no.2
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• pp.1-26
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• 2006

This paper reveals Material Flow Analysis(MFA) has the possibility of reconciling the two contending theoretical viewpoints(weak sustainability v.s. strong sustainability) and thereby makes the concept of sustainability useful at operational level. For this purpose, this paper shows that the theoretical logic of MFA can be applied from national level to product level (EW-MFA, PIOT/NAMEA, LCI), and investigates the meanings and policy implications of MFA at each level.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.142-144
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• 2003

Acetone extracts of 301 strains of marine-derived fungus were tested for antimicrobial activity against three strains of bacteria. The bacteria consisted of three pathogens, Staphylococcus aureus, methicillin-resistant S. Aureus, and multidrug-resistant S. aureus. The acetone extracts of 10 strains (MFA117, MFA130, MFA134, MFA206, MFA217, MFA268, MFA277, MFA291, MFA292, MFA301) showed strong activity, inhibiting 100% of the bacterial growth. These antimicrobial active strains were cultlued in SWS medium on a 1 L scale and the resulting broth and mycelium were extracted to afford mycelium extract (000M) and broth extract (000B), respectively. Antimicrobial activity for all extracts has been tested as the results, the mycelium extract of one strain (217M) and the broth extracts of 9 strains (117B,130B, 134B, 206B, 268B, 277B, 291B, 292B, 301B) exhibited relatively high levels of activity at minimal inhibitory concentration (MIC) values of $500-125\;{\mu}g/mL$ range. Among them, the extracts, 277B, 291B, 292B and 301B showed the most significant antimicrobial activity with $IC_{50}$ values of $125\;{\mu}g/mL$.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.1-30
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• 2020

This study argues that expanding the multifunctionality of agriculture (MFA) may mitigate existing agricultural problems. To do that this study redefines the concept and scope of the MFA and presents practical tasks to achieve it. Theorizing the MFA begins with the theory of sustainability and first identifies the link between sustainability and MFA. Later, considering the limitations of the existing sustainability theories, we examined where the false linkages leading to the destruction of environmental and social relations originated, and employed the (Re)productivity [(Re)produktivitat] theory in order to obtain alternatives. Research shows that welfare effects of the MFA on humans and the environment are not less than those derived from the agricultural products supplied to the real market, but the values are not recognized. The absence of proper care and compensation is the basis of agricultural problems in Korea. Therefore, this study acknowledges that the MFA is as much worthy as real agricultural production, and insists that appropriate compensation and care should be given to humans (farmers) and nature (agricultural ecosystem) in order to maintain and expand the MFA. In other words, a virtuous cycle between sustainability and the MFA means that the process spreads sustainable farming methods to expand the MFA, forms social consensus on it, and pays fair remuneration for agriculture from the public sector. Transition to such a virtuous cycle requires re-establishing the definition and scope of the MFA, implementing targeting policy, motivating policy targets, strengthening human capacity, and arranging maturity time.

• Korean Journal of Pharmacognosy
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• v.33 no.3 s.130
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• pp.219-223
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• 2002

In order to screen new radical scavenging principle which is expected to be antiaging drug lead, we have isolated 160 strains of the marine-derived fungi and investigated 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity for their acetone extracts. The significant activities (>50% Inhibition) were observed in 8 strains of fungi (MFA006, MFA0l4, MFA040, MFA133, MFA139, MFA143, MFA148, MFA153), and among them, MFA153 (Aspergillus parasiticus) showed the most significant radical scavenging activity. The active components were purified by assay-guided isolation to yield two known benzyl alcohols, l53B3 (1) and l53B4 (2), and their structures were determined by physicochemical evidence. Two compounds (1,2) showed the significant radical scavenging activity with $IC_{50}$ values of 0.6 and $1.4{\mu}M$ against DPPH, respectively.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.111-117
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• 2008

The comparative molecular field analysis (CoMFA) for the fungicidal activity with N-phenylbenzenesulfonamide analogues (1-45) against gray mold (Botriyts cinerea) were studied quantitatively. The statistical values of CoMFA models had much better predictability and fitness than those of comparative molecular similarity indices analysis (CoMSIA) models. The statistical values of the optimized CoMFA I model were predictablity, $r^2_{cv.}(or\;q^2)=0.457$ and correlation coefficient, $r^2_{ncv.}=0.959$, and their fungicidal activity was dependent on the steric field (52%) and electrostatic field (35.6%) of the substrate molecules. And also, it was found that the optimized CoMFA I model with the sensitivity to perturbation ($d_q^{2'}/dr^2_{yy'}=0.898$) and prediction ($q^2=0.346$ & SDEP=0.614) produced by a progressive scrambling analysis was not dependent on chance correlation. From the results of graphical analyses on the contour maps with the optimized CoMFA I model, it is expected that the $R_3$ and $R_4$-substituents on the N-phenyl ring as steric favor group and para-substituents ($R_1$) on the S-phenyl ring as steric disfavor group will contribute to the fungicidal activity. Therefore, the optimized CoMFA I model should be applicable to the prediction of the fungicidal activities against gray mold.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.219-225
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• 2002

We have performed a 3D-QSAR/CoMFA analysis of the cytotoxic activities of thirty-five 3-arylisoquinoline derivatives against SK-OV-3 tumor cell line. The results suggested that the electrostatic, steric and hydrophobic factors of 3-arylisoquinolines were strongly correlated with the antitumor activity. Considerable predictive ability (cross-validated r2 as high as 0.841) was obtained through CoMFA.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.138-141
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• 2003

In order to screen new tyrosinase inhibiting principle which is expected to be a new biofunctional skin whitening cosmetics, we have isolated 600 strains of the marine- derived fungi and investigated tyrosinase inhibiting activity for their acetone extracts. The significant activities (>70% Inhibition) were observed in the extract of 10 strains of fungi (MFA7, MFA27, MFA58, MFA317, MFA318, MFA345, MFA412, MFA552, MFA562, MFA581). These active strains were cultured in SWS medium with 1 L scale and the resulting broth and mycelium were extracted to afford mycelium extract (000M) and broth extract (000B), respectively. Tyrosinase inhibiting activity for all extracts has been tested. As the results, the broth extracts of 4 strains (27B, 58B, 552B and 581B) exhibited relatively high levels of activity of $IC_{50}$ values of $3.0-19.0\;{\mu}g/mL$. The active component of 581B was purified by assay-guided isolation to yield the known kojic acid (1), and its structure was determined by physicochemical evidence. Kojic acid showed the significant tyrosinase inhibitory activity with $IC_{50}$ values of $12.0\;{\mu}M$.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.252-257
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• 2005

Three-dimensional quantitative structure-activity relationships (3D-QSARs) for the herbicidal activities against pre-emergence barnyard grass (Echinochloa crus-galli) by new 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpropion amide derivatives were studied quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methodologies. The best CoMFA model (AI-2) and CoMSIA model (AII-4) were derived from an atom based fit alignment and a combination of CoMFA fields. The herbicidal activities from CoMFA and CoMSIA contour maps showed that the activity will be able to be increased according to the substituents variation on the N-phenyl ring.