• Korean journal of applied entomology
• /
• v.43 no.1
• /
• pp.27-34
• /
• 2004

This study was conducted to develop optimal control tactics of the northern root-knot nematode, Meloidogyne hapla, using cultural method and biological agents ｛Bacillus thuringiensis (Bt), Paecilomyces lilacinus and plant extract (Huhjunl)｝ in the fields of Codonopsis lanceolata. Germination of C. lanceolata was susceptible to fosthiazate, but not to Bt or a plant extract. In pot assay, the inhibitory effect of two microbial agents, Bt and Paecilomyces lilacinus, on M. hapla were significant, but less than that of fosthiazate. The plant extract also had significantly inhibitory effect on M. hapla. In field assay, treatments of P lilacinus and fosthiazate resulted in maximal yields and qualities of C. lanceolata. The effect of the plant extract on the yields of C. lanceolata was also better than no treatment. The nematode-occurring condition of the fields before transplanting had significant effect on development of C. lanceolata; nematode-occurring field type gave less yields than nematode-free field type. These results suggest that a cultural control technique using paddy field, microbial pesticides using Bt or P lilacinus, and the plant extract are the promising control tactics against M. hapla in C. lanceolata fields. As a field manual to decrease economical damage of C. lanceolata due to M. hapla, this study suggests that C. lanceolata can be cultured directly in paddy field or in upland field after nematode control using microbial agents or the plant extract.

• Asian Journal of Turfgrass Science
• /
• v.20 no.2
• /
• pp.191-201
• /
• 2006

Dollar spot caused by Sclerotinia homeocarpa is one of major diseases in putting greens. Microorganisms antagonistic to S. homeocarpa, a pathogen of dollar spot, were primarily screened through in vitro tests, including dual culture method and triple layer agar diffusion method. In vivo tests were also conducted to select the best candidate for a biocontrol microorganism, using pot experiment. Bacillus subtilis EW42-1 and Trichoderma harziaum GBF-0208 were finally selected as biocontrol agents against dollar spot. Relative Performance Index(RPI) was used as a criterion of selecting potential biocontrol agents. B. subtilis EW42-1 and T. harzianum GBF-0208 showed resistance to several agrochemicals mainly used in a golf course. B. subtilis EW42-1 and T. harzianum GBF-0208 suppressed effectively the disease progress of dollar spot like synthetic fungicide tebuconazole in the nursery where dollar spot had seriously occurred. B. subtilis EW42-1 and T. harzianum GBF-0208 have a potential to be biocontrol agents for the control of dollar spot.

• Microbiology and Biotechnology Letters
• /
• v.47 no.4
• /
• pp.603-613
• /
• 2019

This study was carried out to examine the antagonistic effect against phytopathogenic fungi of isolated strains from soil samples collected from Busan, Changwon, and Jeju Island: Botrytis cinerea, Colletotrichum acutatum, Corynespora cassiicola, Fusarium sp., Rhizoctonia solani, Phytophthora capsici, and Sclerotinia sclerotiorum. According to results of our studies, isolated strains showed an antagonistic effect against phytopathogenic fungi. Such an antagonistic effect against phytopathogenic fungi is seen due to the production of siderophores, antibiotic substances, and extracellular amylase, cellulase, protease, and xylanase enzyme activities. Extracellular enzymes produced by isolated strains were significant, given that they inhibited the growth of phytopathogenic fungi by causing bacteriolysis of the cell wall of plant pathogenic fungi. This is essential to break down the cell wall of plant pathogenic fungi and thus help plant growth by converting macromolecules, which cannot be used by the plant for growth, into small molecules. In addition, they are putative candidates as biological agents to promote plant growth and inhibit growth of phytopathogenic fungi through nitrogen fixation, indole-3-acetic acid production, siderophore production, and extracellular enzyme activity. Therefore, this study suggests the possibility of using Bacillus subtilis ANGa5, Bacillus aerius ANGa25, and Bacillus methylotrophicus ANGa27 as new biological agents, and it is considered that further studies are necessary to prove their effect as novel biological agents by standardization of formulation and optimization of selected effective microorganisms, determination of their preservation period, and crop cultivation tests.

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.487-492
• /
• 2005

Simple competition plate bioassays of Pichia anomala SKM-T and Galactomyces geotrichum SJM-59 were conducted to evaluate their potential as biological control agents that inhibit growth of Botrytis cinerea during post-harvest storage of strawberries (Fragaria ${\times}$ ananassa Duche, Red-Pearl). Occurrence rates of fungi on the surface of yeast-treated strawberries were evaluated during storage at $4^{\circ}C$. P. anomala SKM-T and G. geotrichum SJM-59 showed antifungal activities on agar plate, and P. anomala SKM-T maintained its desirable antifungal activity on surface of strawberries and its physicochemical properties during storage. Sensory evaluation was based on kinesthetics and consumer acceptability. Due to its potential antifungal activity, P. anomala SKM-T could function as biological control agent against spoilage fungi during post-harvest storage of strawberries.

• BMB Reports
• /
• v.29 no.3
• /
• pp.248-252
• /
• 1996

The epidermal organ of the leech contains a complex glycoprotein molecule of mucus. The mucus excreted from annelids plays Significant role in protection against desiccation and parasites. Mucus from the Korean native leech, H. nipponia, was investigated for biochemical characteristics for possible development of biomaterials of cosmetic and pharmaceutical agents. The leech skin mucus was heavily glycosylated mucin-like protein with a high molecular weight comprised 80% carbohydrate and 20% protein. Threonine, serine, and glycine were the major components of the isolated protein and these accounted for 50% of total amino acids. The carbohydrate portion contained glucosamine, galactosamine. galactose, glucose. mannose and sialic acid in oligosaccharide form linked with threonine and serine residues of the glycoprotein.

• Korean Journal of Environmental Biology
• /
• v.22 no.2
• /
• pp.336-340
• /
• 2004

In order to search for anti -melanin formation agents from Korean medicinal herbs, we selected 21 Korean medicinal herbs, based on a review of Korean traditional medicine books and the recommendations of Korean traditional medical doctors. We tested for inhibition effect of melanin pigmentation of Clone M-3 mouse melanocyte cell lines when we treated the extracts of 21 medicinal herbs in the mouse melanocyte cell lines, respectively. Among 21 medicinal herb extracts, 5 extracts showed a inhibition effect of melanin formation. The sample Phaseolus radiatus L, Cordyceps militaris, Pinellia ternata, Phellinus linteus and Citrus junos Tanaka showed a significantly little formation of melanin pigments compared with control groups. Especially extract of Citrus junos Tanaka was more potent than the others. These results suggest that extract of Korean Citrus junos may represents an excellent candidate for inhibition of melanin pigmentation at in vitro level.

• Korean Journal of Pharmacognosy
• /
• v.48 no.1
• /
• pp.10-17
• /
• 2017

Ursi Fel's component ursodeoxycholic acid (UDCA), a traditional medicine, is used for the treatment of hepatic diseases. UDCA derivatives prepared by conjugation with antioxidant moiety such as maltol, sesamol, eugenol, mesitol and 3,4-(methylenedeoxy)aniline were expected to have various biological activity caused by synergistic effect of UDCA. Therefore, in this study, it was conducted the study of the manufacture of the UDCA derivatives and their biological activity. As a result, UDCA derivatives showed weak antioxidant activity in TBA method in vitro compared to original agents. SJ-505, SJ-502 and SJ-504 showed the effect of reducing ALT, AST, sorbitol dehydrogenase and ${\gamma}-glutamyltransferase$ in $CCl_4-induced$ liver injury experiment in vivo, even if the effects are weaker than UDCA and silymarin of the control group.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.3
• /
• pp.534-538
• /
• 2007

Avermectin and its analogs are major commercial antiparasitic agents in the fields of animal health, agriculture, and human infections. To increase our understanding about the genetic mechanism underlying avermectin overproduction, comparative transcriptomes were analyzed between the low producer S. avermitilis ATCC31267 and the high producer S. avermitilis ATCC31780 via a S. avermitilis whole genome chip. The comparative transcriptome analysis revealed that fifty S. avermitilis genes were expressed at least two-fold higher in S. avermitilis ATCC31780. In particular, all the avermectin biosynthetic genes, including polyketide synthase (PKS) genes and an avermectin pathway-specific regulatory gene, were less expressed in the low producer S. avermitilis ATCC31267. The present results imply that avermectin overproduction in S. avermitilis ATCC31780 could be attributed to the previously unidentified fifty genes reported here and increased transcription levels of avermectin PKS genes.

• CELLMED
• /
• v.6 no.4
• /
• pp.22.1-22.19
• /
• 2016

The biologically active compounds derived from different natural organisms such as animals, plants, and microorganisms like algae, fungi, bacteria and merine organisms. These natural compounds possess diverse biological activities like anthelmintic, antibacterial, antifungal, antimalarial, antiprotozoal, antituberculosis, and antiviral activities. These biological active compounds were acted by variety of molecular targets and thus may potentially contribute to several pharmacological classes. The synthesis of natural products and their analogues provides effect of structural modifications on the parent compounds which may be useful in the discovery of potential new drug molecules with different biological activities. Natural organisms have developed complex chemical defense systems by repelling or killing predators, such as insects, microorganisms, animals etc. These defense systems have the ability to produce large numbers of diverse compounds which can be used as new drugs. Thus, research on natural products for novel therapeutic agents with broad spectrum activities and will continue to provide important new drug molecules.

• Korean Journal of Biological Psychiatry
• /
• v.23 no.1
• /
• pp.1-11
• /
• 2016

Development of various antidepressants such as monoamine oxidase inhibitors, tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, and noradrenergic and specific serotonergic antidepressant has led to a tremendous progression of pharmaceutical treatment for depression, but still there are some limitations of current antidepressants, such as treatment-resistant depression and delayed onset of antidepressants. The pathogenesis of depression is unclear because depression is a heterogeneous disease state, and the mechanisms of antidepressants remain uncertain as well. Nevertheless, in an attempt to develop novel antidepressants, some trials have been conducted based on the potential biological mechanism discovered in the numerous research results. This review will provide information about the potential novel antidepressants and the current states of clinical studies using them. In particular, some potential novel antidepressants anti-inflammatory agents, antioxidants, anticholinergics, modulators of Hypothalamic Pituitary Adrenal Axis, glutamate, and opioid systems, as well as some neuropeptides such as susbstance P, neuropeptide Y, and galanin will be discussed.