• Korean Journal of Pharmacognosy
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• v.26 no.4
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• pp.355-359
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• 1995

To find serotonin(5-hydroxytryptamine, 5-HT)-antagonizing activities in traditional herbal drugs, crude extracts from 66 kinds of traditional herbal drugs were randomly screened for inhibitory effects on 5-hydroxytryptophan(HTP)-induced diarrhea in mice. Intraperitoneal injection of 5-HTP(2.5 mg/kg) induced diarrhea in 92% of mice, when observed from 10 to 15 min after injection. Crude extracts(2 g/kg) from 66 kinds of traditional herbal drugs were orally pretreated for 1 h before 5-HTP injection. Of the 66 herbal drugs screened, Ephedrae Herba(麻黃), Cimicifugae Rhizoma(升麻), Anisi stellati Fructus(八角茴香), Aurantii Fructus(枳實), Polygalae Radix(遠志) showed the most potent inhibiting activities against 5-HTP(2.5 mg/kg)-induced diarrhea in mice. There are at least 3 possible mechanisms that would be responsible for the inhibitory effect of crude extracts on 5-HTP-induced diarrhea; 1) crude extract-induced inhibition of the activity of aromatic aminoacid decarboxylase catalyzing the conversion of 5-HTP to 5-HT, 2) crude extract-induced blockade of 5-HT receptor(s) in the gastrointestinal tract responsible for 5-HTP-induced diarrhea, 3) crude extract-induced inhibition of gastrointestinal activity, irrespective of 5-HT system. The exact mechanisms and molecules, responsible for the inhibitory effect of crude extracts on 5-HTP-induced diarrhea remain to be clarified.

• Korean Journal of Pharmacognosy
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• v.3 no.4
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• pp.199-204
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• 1972

A new physico-chemical method for identifying botanical drugs was investigated. Fifty drugs were chosen from the presently exported botanical drugs and were classified into 12 groups chemotaxonomically. Various extract(either, 50% ethanol and water) of each group were developed with same solvent system by using chromatographic method(TLC) and observed a characteristic pattern of each drugs. This method, therefore, can be applicable to identify each botanical drug out of the combined phyto-preparations.

• Korean Journal of Pharmacognosy
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• v.13 no.3
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• pp.116-121
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• 1982

In order to investigate the side-effects of crude drugs, twenty drugs have been tested for the teratogenic effect in rats. Among seven drugs contained alkaloid as their ingredients, no one showed teratogenic effect, but Veratri rhizoma showed embryo-toxic as revealed by severe retardation in growth of the fetuses. The other thirteen drugs which have been used freguently in oriental medicines exhibited no teratogenic effect. Cyclophosphamide used as a reference compound showed severe malformation and retardation in the growth of rat fetuses. These findings suggest that the drug extracts adopted for the study might have no teratogenic effect in the rats.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.15-24
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• 2019

Neural stem cells (NSCs) can proliferate and differentiate into multiple cell types that constitute the nervous system. NSCs can be derived from developing fetuses, embryonic stem cells, or induced pluripotent stem cells. NSCs provide a good platform to screen drugs for neurodegenerative diseases and also have potential applications in regenerative medicine. Natural products have long been used as compounds to develop new drugs. In this review, natural products that control NSC fate and induce their differentiation into neurons or glia are discussed. These phytochemicals enable promising advances to be made in the treatment of neurodegenerative diseases.

• Korean Journal of Pharmacognosy
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• v.50 no.1
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• pp.1-10
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• 2019

Recently, companion animal culture has grown rapidly and mature, raising interest in preventing and treating animal diseases. In particular, viral infection was a serious threat to companion animal health because there was no proper antiviral drugs. Synthetic antiviral drugs have limitations such as low efficiency, toxicity, and occurrence of resistant viruses. Therefore, attempts to find new anti-viral drugs from natural sources have continued. This review focused on the natural products and active substances that exhibit antiviral activity against three viruses: canine distemper virus (CDV), canine parvovirus (CPV), and feline calicivirus (FCV) that cause fatal diseases in dogs and cats. Natural plant extracts, flavonoids, polysaccharides, alkaloids and saponins showed antiviral activity with various mechanisms and differences in activity depending on the structure. Especially, quercetin and epigallocatechin-3-gallate (EGCG) showed antiviral activity through a multi-mechanism that interferes with the attachment and penetration stages of the virus and inhibits the viral polymerase within the cell. Some natural plant extracts showed a virucidal activity and showed the potential effect as a preventative agent to prevent the viral infection. This review is expected to provide research trend on the development of antiviral natural products for companion animals.

• YAKHAK HOEJI
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• v.15 no.1
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• pp.1-7
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• 1971

When a large quantity of insoluble drugs was added into a solution containing a small amount of soluble drugs, the latter was adsorbed to the former. Their adsorption was expected to alter the drug activity. Berberine hydrochloride (BH) was selected as a soluble drug and tested with frequently combined insoluble drugs and antacids for their adsorption phenomena in prufied water, gastric and intetinal fluid test solutions, respectively. The adsorption isotherms of kaolin and natural anuminum silicate with BH in the three media fitted the Langmuir (LM) equation, and that of talc in purified water and gastric fluid fitted it, but in intestinal fluid it fitted the Freudlich quation. The adsorption isotherm of aluminum hydroxide fitted the LM equation only in intestinal fluid. The degree of adsorption of BH in purified water and gastric fluid is in the following order: magnesium trisilicate, kaolin, natural aluminum silicate and talc; in intestinal fluid: magnesium trisilicate, kaolin, talc, natural aluminum silicate and aluminum hydroxide. Magnesium stearate did not adsorb BH.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.14-23
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• 1995

The current study was undertaken to select the crude drug showing life prolonging effect on the starved rats(Sprague-Dawley) and elucidate the reaction mechanism there of. As distilled water extracts prepared from twenty kinds of natural drugs were administered orally to female starved rats, Bupleuri Radix demonstrated the most prominent effect with 34.6% increment in the survival time. To investigate underlying mechanism of life prolonging effect of Bupleuri Radix, the concentrations of adrenocorticosteroids(corticsterone, testosterone and aldosterone) and enzyme activities of superoxide dismutase(SOD), glutamate oxaloacetate transaminase(GOT), glutamate pyrurate transaminase(GPT) were assayed in the serums of rats starved for, 2, 4 and 6 days respectively. The results manifested much elevated values of corticosterone, aldosterone(2 days) and rather decreasing tendency afterwards, specially in the late periods of starvation(6 days). With respect to such a considerable changes according to starvation periods, Bupleur Radix restored these values much near to normal suggesting that Buplerum Radix may play a life prolonging action during starvation probably through reinforcing the homeostatic properties of corticosteroids and some enzyme activities.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.93-97
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• 1993

We have previously reported that an NADPH-dependent succinic semialdehyde reductase was purified homogeneously from bovine brain by several chromatographic procedures, and was found to be a monomeric protein with a molecular mass of 28 kDa (Cho et al., Eur. J. Biochem. 1993). Since succinic semialdehyde is an important intermediate in the ${\gamma}$-aminobutyrate(GABA) shunt and GABA level is associated with various forms of human neurological disorders, we have investigated the effects of anticonvulsant drugs on the succinic semialdehrde reductase. Among the drugs tested, sodium valproate and diphenylhydantoin inhibited the enzyme activity, while some other drugs, barbiturate and chlorpromazine, had no inhibitory effects on the enzyme activity. The purified enzyme was also injected as an immunogen into Balb/c mice to obtain monoclonal antibodies (mob) and several mobs to the protein were produced from the fusion experiments.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.651-660
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• 2006

Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.214-219
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• 1998

Tissue distributions and association of cyclooxygenase-2 (COX-2) with inflammatory have led us to search for COX-2 selective inhibitors from natural products. Conceptually, COX- 2 selective inhibitors should be expected to retain anti-inflammatory efficacy by inhibition of PGs production while reducing or eliminating the gastric, renal and hemostatic side effects commonly associated with NSAIDs use. Thus, a logical approach to the treatment of inflammatory diseases should involve the inhibitors of COX-2. To develop new COX-2 inhibitors from natural products, two hundred crude drugs were screened by inhibiting PGD2 generation in bone marrow derived mast cells (BMMC). Among them, 6 methanol extracts of crude drugs such as, Bletillae rhizoma, Aconiti kgreani rhizoma, Belamcandae rhizoma, Nelumbinis semen, Gleniae radix, Aurantii immatri pericarpium inhibited more than 85% of BMMC COX-2 activity at a concentration 2.5${\mu}$g/ml.