• The Korean Journal of Pesticide Science
• /
• v.5 no.3
• /
• pp.1-11
• /
• 2001

New technologies will have a large impact on the discovery of new herbicide site of action. Genomics, combinatorial chemistry, and bioinformatics help take advantage of serendipity through tile sequencing of huge numbers of genes or the synthesis of large numbers of chemical compounds. There are approximately $10^{30}\;to\;10^{50}$ possible molecules in molecular space of which only a fraction have been synthesized. Combining this potential with having access to 50,000 plant genes in the future elevates tile probability of discovering flew herbicidal site of actions. If 0.1, 1.0 or 10% of total genes in a typical plant are valid for herbicide target, a plant with 50,000 genes would provide about 50, 500, and 5,000 targets, respectively. However, only 11 herbicide targets have been identified and commercialized. The successful design of novel herbicides depends on careful consideration of a number of factors including target enzyme selections and validations, inhibitor designs, and the metabolic fates. Biochemical information can be used to identify enzymes which produce lethal phenotypes. The identification of a lethal target site is an important step to this approach. An examination of the characteristics of known targets provides of crucial insight as to the definition of a lethal target. Recently, antisense RNA suppression of an enzyme translation has been used to determine the genes required for toxicity and offers a strategy for identifying lethal target sites. After the identification of a lethal target, detailed knowledge such as the enzyme kinetics and the protein structure may be used to design potent inhibitors. Various types of inhibitors may be designed for a given enzyme. Strategies for the selection of new enzyme targets giving the desired physiological response upon partial inhibition include identification of chemical leads, lethal mutants and the use of antisense technology. Enzyme inhibitors having agrochemical utility can be categorized into six major groups: ground-state analogues, group specific reagents, affinity labels, suicide substrates, reaction intermediate analogues, and extraneous site inhibitors. In this review, examples of each category, and their advantages and disadvantages, will be discussed. The target identification and construction of a potent inhibitor, in itself, may not lead to develop an effective herbicide. The desired in vivo activity, uptake and translocation, and metabolism of the inhibitor should be studied in detail to assess the full potential of the target. Strategies for delivery of the compound to the target enzyme and avoidance of premature detoxification may include a proherbicidal approach, especially when inhibitors are highly charged or when selective detoxification or activation can be exploited. Utilization of differences in detoxification or activation between weeds and crops may lead to enhance selectivity. Without a full appreciation of each of these facets of herbicide design, the chances for success with the target or enzyme-driven approach are reduced.

• Korean Journal of Food Science and Technology
• /
• v.50 no.5
• /
• pp.535-542
• /
• 2018

The current study investigated the beneficial effects of 15 essential oils isolated from tree branches, leaves, and flowers. Among these oils, clove bud and Illicium anisatum oils showed the most potent anti-oxidant effects on 1,1-diphenyl-2-picrylhydrazyl and 2,2'azinbis-(3-ethyl-benzothiazoline-6-sulfonic acid) radical scavenging activities. Next, we evaluated the antibacterial effects of 15 essential oils on Staphylococcus aureus, Listeria monocytogenes, Escherichia coli O157:H7, Salmonella typhimurium, and Streptococcus mutans. Clove bud significantly decreased growth of 5 bacterial strains. In addition, clove bud, Magnolia kobus, Picea abies and Chamaecyparis obtuse significantly reduced growth of the fungi, Aspergillus fumigatus, Aspergillus ochraceus, Candida albicans and Trichophyton rubrum. Additionally, clove bud also remarkably reduced the expression of cyclooxygenase-2 and inducible NO synthase in lipopolysaccharide-activated RAW264.7 cells. These results indicate that essential oils isolated from trees, which exhibit antioxidant, antibacterial, antifungal and anti-inflammatory properties, may be potentially useful in the development of cosmetic ingredients.

• The Korean Journal of Pharmacology
• /
• v.28 no.2
• /
• pp.129-136
• /
• 1992

As it has been reported that the depolarization-induced acetylcholine (ACh) release is modulated by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus and various lines of evidence indicate the involvement of adenylate cyclase system in $A_1-adenosine$ post-receptor mechanism in hippocampus, it was attempted to delineate the role of adenylate cyclase system in the $A_1-receptor-mediated$ control of ACh release in this study. Slices from rat hippocampus were incubated with $[^3H]-choline$ and the release of the labelled products was evoked by electrical stimulation $(3\;Hz,\;5\;Vcm^{-1},\;2\;ms,\;rectangular\;pulses)$, and the influence of various agents on the evoked tritium-outflow was investigated. $N^6-cyclopentyladenosine$ (CPA), a specific $A_1-adenosine$ receptor agonist, in concentrations ranging from 0.1 to $10\;{\mu}M$, decreased the $[^3H]-ACh$ release in a dose-dependent manner without the changes of basal rate of release. 8-cyclopentyl-1,3-dipropylxanthine $(DPCPX,\;1{\sim}10\;{\mu}M)$, a selective $A_1-receptor$ antagonist, increased the $[^3H]-ACh$ release in a dose-related fashion with slight increase of basal tritium-release. And the CPA effects were significantly inhibited by DPCPX $(2\;{\mu}M)$ pretreatment and the dose-response curve produced by CPA was shifted to the right. The responses to N-ethylmaleimide $(NEM,\;10\;&\;30\;{\mu}M)$, a SH-alkylating agent of G-protein, were characterized by increments of the evoked ACh-release and the basal release, and the CPA effect were completely abolished by NEM pretreatment. Forskolin, a specific adenylate cyclase activator, in concentrations ranging from 0.3 to $10\;{\mu}M$, increased the evoked ACh-release in a dose-dependent manner and the CPA effects were inhibited by forskolin. These results indicate that the $A_1-adenosine$ heteroreceptor plays an important role in ACh-release via nucleotide-binding protein Gi in the rat hippocampus and that the adenylate cyclase system might be participated in this process.

• Journal of Nutrition and Health
• /
• v.42 no.8
• /
• pp.702-713
• /
• 2009

This study was conducted to estimate the prevalence of constipation, bowel habits and nutrient intakes of college students. The subjects were 353 college students (166 males and 187 females) aged 19 to 29 years in Incheon area. The subjects were asked about bowel habits and dietary intake using questionnaires during march, 2008 and the prevalence of functional constipation (FC) was based on the Rome II criteria. The prevalence of FC in male and female students was 12.7% and 28.9%, respectively. The prevalence of self-reported constipation in male and female students was 12.0% and 36.9%, respectively. Both were higher in female students compared to male students. Among the subjects that have self-reported constipation, proportions of FC were 35.0% in male students and 55.1% in female students. Of subjects that did not self-reported constipation, the proportions of FC were 9.6% in male students and 13.6% in female students. Over 90% of respondents that self-reported constipation in male students, had neither visited a hospital and nor used laxatives or functional foods for constipation relief. Seventy five point three percent of male students, and 40.1% of female students, had a defecation frequency of over 5 times per week (p < 0.001). Ratios intaken under the estimated average requirement (EAR) of Vit A, Vit C, folic acid and Ca were over the 50% regardless of functional constipation. Mean daily consumption of total dietary fiber was 15.0 g/day in male students and 13.5 g/day in female students. According to these results, both functional constipation and self-reported constipation are more frequent in female college students and further studies are required in case-control study and related to psychological factors as well as nutrients to relieve of constipation.

• KSBB Journal
• /
• v.21 no.6 s.101
• /
• pp.466-473
• /
• 2006

Impaired insulin secretion from pancreatic beta-cells in response to glucose is an important feature in the pathology of non-insulin-dependent diabetes mellitus (NIDDM). In the course of screening for useful insulin secretagogues, we have isolated and identified YHB-2017 (Genistein) as a insulin secretion potentiator from fermentation broths of our in-house microbial library. The insulinotropic activity of YHB-2017 in isolated rat pancreatic islets was exerted only at high concentration of glucose (8.3-16 mM) but not at low concentration of glucose (3.3-5.5 mM). Also, in perifusion study with isolated rat pancreatic islets, YHB-2017 stimulated insulin secretion in a time-dependent manner when YHB-2017 was added to KRB buffer containing 16 mM glucose. In the presence of $200\;{\mu}M$ diazoxide and 35 mM KCI, which stimulates maximum $Ca^{2+}$ influx independently of KATP channel, YHB-2017 enhanced KATP channel-independent insulin secretion at high concentration glucose (16 mM). To elucidate the mechanisms of the glucose-dependent potentiation effect of YHB-2017, pharmacologic inhibitors for protein kinase A, protein kinase C and calcium/calmodulin kinase II were pre-treated and then the potentiation effect of YHB-2017 on insulin secretion was investigated. Pre-treatment of H89 as a PKA inhibitor had a significant inhibitory effect on YHB-2017-induced potentiation effect. Furthermore, western immunoblotting analyses revealed that YHB-2017 increased phosphorylation of PKA substrates and cAMP response element-binding protein (CREB) under high concentration of glucose. These results demonstrated that the insulinotropic effect of YHB-2017 is mediated through PKA signal pathway and activated amplifying $K_{ATP}$ channel-independent insulin secretion pathway.

• Journal of Chest Surgery
• /
• v.39 no.9 s.266
• /
• pp.659-667
• /
• 2006

Background: Experimental studies of vascular remodeling in the pulmonary arteries have been performed actively. These models required a persistent vascular insult for intimal injury induced by chronic hypoxia, monocrotaline intoxication or chronic air embolism and characterized medial hypertrophy and neointimal formation by active synthesis of the extracellular matrix protein. The purpose of this study was to determine the pattern of pulmonary vascular remodeling after obstruction of the pulmonary vein. Material and Method: Obstruction of the right pulmonary vein with a metal clip was performed in Sprague-Dawley rats $(352{\pm}18g,\;n=10)$ to cause pulmonary vascular disease. Fifteen days later, experimental studies were done and finally the both lungs and hearts were extirpated for experimental measurement. Pulmonary arterial pressure, weight ratio of right ventricle (RV) to left ventricle (LV) and ventricular septum (S) (RV/LV +S weight ratio), and pulmonary artery morphology (percent wall thickness, %WT) were evaluated and compared with normal control groups. Result: Pulmonary hypertension $(38{\pm}12mmHg\;vs\;13{\pm}4mmHg;\;p<0.05)$ and right ventricular hypertrophy (right ventricular/left ventricular and septal weight ratio, $0.52{\pm}0.07\;vs\;0.35{\pm}0.04;\;p<0.05$) with hypertrophy of the muscular layer of the pulmonary arterial wall (percent wall thickness, $22.4{\pm}6.7%\;vs\;6.7{\pm}3.4%;\;p<0.05$) were developed by 15 days after obstruction of the pulmonary vein. Conclusion: Obstruction of the pulmonary vein developed elevation of pulmonary blood pressure and medial hypertrophy of the pulmonary artery. These results are a part of the characteristic vascular remodeling. Theses results demonstrate that obstruction of the pulmonary vein can develope not only high pulmoanry blood flow of contralateral lung but also intima injury inducing vascular remodeling.

• Korean Journal of Food Science and Technology
• /
• v.42 no.4
• /
• pp.475-480
• /
• 2010

The fruit of Actinidia polygama, Mock-chun-ryo in Korea, has been used as traditional medicine for abdominal pain, rheumatic arthritis, and stroke. In a previous study, the ethanol extract of A. polygama Max. showed antiinflammatory activity in RAW 264.7 cells. In this study, we investigated the anti-inflammatory and anti-atherosclerosis effects of supercritical fluid marc extracts from A. polygama Max. Anti-inflammatory extracts were produced from supercritical fluid extraction of the silver vine under the following conditions; pressure, 1,500-4,500 psi, temperature $35-55^{\circ}C$ and extraction time 1-2 hr. To evaluate the anti-inflammatory and anti-atherosclerotic effects of the extracts, we studied nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), and tumor necrosis factor-alpha (TNF-$\alpha$) levels in RAW 264.7 cells and MMP-9 activity in human aortic smooth muscle cells (HASMC). The Marc 11 extract inhibited the production of NO, $PGE_2$, and TNF-$\alpha$ by lipopolysaccharide in RAW 264.7 cells. Moreover, the marc 11 extract inhibited TNF-$\alpha$-induced MMP-9 activity in HASMC. These results indicate that the Marc 11 extract of A. polygama Max. has the potential for use as an anti-atherosclerosis agent.

• Journal of Life Science
• /
• v.19 no.1
• /
• pp.15-20
• /
• 2009

Uncoupling protein 3 (UCP3) is a mitochondrial protein that is expressed predominantly in skeletal muscle. It may play a role in altering metabolic function. However, its major physiological roles are not fully understood. Recently de novo expression of UCP3 in rat liver by fenofibrate was reported. We also reported previously that fenofibrate-induced de novo expression of UCP3 contributes to reduction of adipose tissue in obese rats. In the present study, we investigated that ienofibrate-induced expression of UCP3 in rat liver is related with metabolic function such as body weight and hepatic lipid content by time-dependent manner in high-fat diet rats. Eight-week-old male Sprague-Dawley rats were randomly divided into two groups; the high fat diet group (HF, n=16) and fenofibrate-treated high fat diet group (HFF, n=16). The mRNA expression of hepatic UCP3 was detected as early as 1 week of fenofibrate treatment by quantitative real-time PCR and the amount of mRNA was increased time-dependently. The mean body weight of the HFF group was significantly less com. pared with the HF group after 6 weeks of fenofibrate treatment, even though there was no difference of food intake between the two groups. Rectal temperature was increased during 4 to 6 weeks of fenofibrate treatment and body weight was decreased after 6 weeks of treatment. These results were corresponded with the increased amount of the expression of UCP3 mRNA and protein. We suggest that de novo expression of hepatic UCP3 is increased time-dependently with fenofibrate treatment and that the amount of expression is correlated with metabolic function.

• Korean Journal of Food Science and Technology
• /
• v.5 no.3
• /
• pp.169-173
• /
• 1973

Secondary amines and nitrites in various daily foods have been known as the precursors of potent carcinogenic nitroso compound produced in the human stomach when they were ingested simultaneouly in high concentration. In this report, the amounts and distribution of secondary amines and nitrites in Korean daily foods, kim-chi, fishes, fish eggs, sausages, canned fish foods and fish sauces (salted fish) were studied.Nitrite contents were low in most subjected foods except in sausages. Secondary amines showed low contents in kim-chi, fishes, but high in fish sauces, fish eggs and canned fish foods. The result of this study suggested that the possible formation of carcinogenic nitrosamines during manufacturing, storage and cooking of all Korean foods should be studied.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.7
• /
• pp.779-789
• /
• 2017

The effects of orally administered Seomaeyakssuk (Artemisia argyi H.) vinegar on lipid metabolism in Sprague-Dawley rats fed a high-fat and high-cholesterol (HFC) diet were analyzed. The experimental animals were divided into five groups: a normal diet group (normal, N), HFC diet group (control, C), HFC diet with lovastatin at 20 mg/kg body weight (B.W.) group (positive control, PC), HFC diet with malt vinegar group (TM), and HFC diet with Seomaeyaksuk vinegar group (TS) (2 mL/kg B.W.). After 4 weeks of feeding rats the experimental diet, contents of serum total lipids and total cholesterol levels of TM and TS groups were significantly lower than those of the PC group. Triglyceride contents of the TM and TS groups were not significantly different from those of the PC group but significantly lower than those of the C group. Content of serum high density lipoprotein-cholesterol was significantly lower than that of the N group but higher than that of the C group. Low density lipoprotein-cholesterol content of serum was 190.68 mg/dL in the TS group, which was the lowest except for the N group. Aspartate transaminase and albumin transaminase activities as a measurement of liver damage index were not significantly different between the TM, TS, and C groups. Serum thiobarbituric acid reactive substance content of the TS group was reduced to a similar level as the N group but was lower than that of the C group in the liver and significantly higher than that of the N group. Antioxidant activity of the TS group was 55.69% in serum, which was a similar to that of the N group, and was 52.39% in the liver, which was not significantly different than that of the C group. From these results, we conclude that Seomaeyakssuk vinegar improves serum lipid content as a result of the complex action of vinegar, an active ingredient of Seomaeyakssuk and a product of the fermentation process.