• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.68-74
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• 2012

BACKGROUND: Some microorganisms extant in nature have ability to suppress various plant pathogens, and also can promote plant growth. Thus microorganisms are such great source of antimicrobial agents to develop antagonistic microorganism production and eco-friendly crop management. We isolated the microorganisms in various eco-friendly formulations. The suppressive abilities against plant pathogens have been characterized in vitro level. METHODS AND RESULTS: The indigenous microorganisms have been isolated from Cooked rice, Black sugar, Rice Bran, and Red clay using dilution plating method. Population of bacteria and fungi were above 107 in the all formulations. We isolated and pure cultured the microorganisms based on morphological characteristics. Three major plant pathogens (Fusarium oxysporum, Rhizoctonia solani, Phytophthora capsici) have been used to select antagonistic microorganisms. Total 20 bacteria and 9 fungi showed the pathogen growth suppression ability in vitro condition. The selected microorganisms were identified by ITS sequence similarity. CONCLUSION: All tested eco-friendly formulations contained high-density of the microorganisms. Among the isolated microorganisms, Bacillus spp. and Streptomyces spp. showed the most effective antifungal activity against the plant pathogens such as F. oxysporum, R. solani, and P. capsici. Among the selected fungi Trichoderma sp. demonstrated antifungal activity. Our results suggest that the currently adapted eco-friendly formulations might useful for sustain agricultural system.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.165-174
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• 1993

$Ca^{2+}$ is an important regulator of neurite elongation and growth cone movements but the mechanism(s) mediating these $Ca^{2+}-dependent$ effects is unclear. Since cytoskeletal proteins are rapidly degraded by $Ca^{2+}-dependent $ proteinases (calpains) in vitro and in vivo, we investigated whether $Ca^{2+}-induced$ pruning or regression of neuronal processes is mediated by calpains. Isolated hippocampal pyramidal-like neurons were cultured and the ability of the membrane-permeable calpain inhibitors EST (etyl (+)-(2S,3S)-3-[(S)-methyl-1-(3-methlbutylcarbamoyl)-butylcarbamoyl]2-oxiranecarboxylate) and MDL28170 (carbobenzoxyl-Val-Phe-H) to block the $Ca^{2+}$ ionophore A23187-induced suppression in neurite outgrowth was investigated. Addition of 100 nM A23187 to the culture medium resulted in a retraction of dendrites without altering axonal elongation. The addition of 300 nM A23187 to the culture medium resulted in a signiciant decrease in the rate of axonal elongation as well as a retraction of dendritic processes. Administration of EST $(5\;or\;20{\mu}M)$ to the culture medium completely blocked the pruning effect of 100 nM A23187 on dendrites and of 300 nM A23187 on axons, while EST alone did not significantly affect neurite outgrowth rate. MDL 28170 $(20\;{\mu}M)$ showed the same effect as EST in preventing ionophore-induced pruning of dendrites and axons at 100 nM and 300 nM concentrations, respectively, of A23187. EST $(20\;{\mu}M)$ did not block the A23187-induced rise of $[Ca^{2+}]_{i}$ as measured with fura-2. These results show that $Ca^{2+}-induced$ pruning of neurites in isolated hippocampal pyramidal neurons is mediated by calpains.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.62-68
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• 1984

This experiment was conducted to find out the possibility for reducing herbicidal dose of the recommended herbicides in combining with the plant growth regulator "chlorflurenol" at the Yeongnam Crop Experiment Station, from 1981 to 1982. Chlorflurenol itself exhibited weed suppression effect against Monochoria raginalis Presl., Rotala indica Koehne, Cyperus difformis L., Lindernia procrembens Philcox, etc. and its effect increased as the concentrations of chlorflurenol increased from 100 to 1,000 ㎖/㏊. Combination of chlorflurenol with butachlor or thiobencarb, showing synergistic effect, reduced their recommended herbicidal rates by 50 to 75%, showing 90% of weed control rate, stic but combined treatment between chlorflurenol and bentazon showed an antagonistic effect since bentazon had poor control ability to Echinochloa crusgalli Beauv. An application of chlorflurenol showed no significant effect on rice growth, in terms of dry weight, but it resulted in the decrease in the ratio of leaf blade to other non-photosynthetic organ.

• Journal of Dairy Science and Biotechnology
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• v.37 no.3
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• pp.155-166
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• 2019

Bacteria from the genus Lactobacillus are important for the production of fermented food and dairy products, and as symbionts in human and animals. Lactobacillus acidophilus has widely been used in the production of yogurt, health foods, and even medicines. The efficacy of L. acidophilus has been proven with regards to the reduction of cholesterol, prevention and treatment of diarrhea, modulation of the immune system, suppression of cancer, etc. Using molecular biology tools, Lactobacillus acidophilus has now been reclassified into six species: L. acidophilus, L. amylovorus, L. crispatus, L gallinarium, L. gasseri, and L. johnsonii. Thus, since L. acidophilus has now been marked as a newly defined species, caution is advised when reading future publications regarding this bacterium. In this article, the results of the reclassification of L. acidophilus are mentioned after an analysis of its field inheritance was performed by my research team. Especially, L. amylovorus KU4 (formerly named as L. acidophilus KU4; KCCM 10975P) is a novel probiotic strain that is isolated from humans; it has the ability to reduce cholesterol. It has also been reported as a microorganism that effectively inhibits the growth of pathogenic E. coli. However, this Korean patent (No 10-1541280) refers to a strain obtained from calves; the origin of this strain was incorrectly labeled. Furthermore, after the discovery of L. acidophilus in 1900, its role in intestinal microbiological research was described and its utilization as a probiotic was presented.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4615-4619
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• 2013

Background: Artesunate, extracted from Artemisia annua, has been proven to have anti-cancer potential. Allicin, diallyl thiosulfinate, the main biologically active compound derived from garlic, is also of interest in cancer treatment research. This object of this report was to document synergistic effects of artesunate combined with allicin on osteosarcoma cell lines in vitro and in vivo. Methods: After treatment with artesunate and allicin at various concentrations, the viability of osteosarcoma cells was analyzed by MTT method, with assessment of invasion and motility, colony formation and apoptosis. Western Blotting was performed to determine the expression of caspase-3/9, and activity was also detected after drug treatment. Moreover, in a nude mouse model established with orthotopic xenograft tumors, tumor weight and volume were monitored after drug administration via the intraperitoneal (i.p.) route. Results: The viability of osteosarcoma cells in the combination group was significantly decreased in a concentration and time dependent manner; moreover, invasion, motility and colony formation ability were significantly suppressed and the apoptotic rate was significantly increased through caspase-3/9 expression and activity enhancement in the combination group. Furthermore, suppression of tumor growth was evident in vivo. Conclusion: Our results indicated that artesunate and allicin in combination exert synergistic effects on osteosarcoma cell proliferation and apoptosis.

• Experimental and Molecular Medicine
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• v.50 no.12
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• pp.10.1-10.11
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• 2018

Cancer growth and progression are associated with immune suppression. Cancer cells have the ability to activate different immune checkpoint pathways that harbor immunosuppressive functions. Monoclonal antibodies that target immune checkpoints provided an immense breakthrough in cancer therapeutics. Among the immune checkpoint inhibitors, PD-1/PD-L1 and CTLA-4 inhibitors showed promising therapeutic outcomes, and some have been approved for certain cancer treatments, while others are under clinical trials. Recent reports have shown that patients with various malignancies benefit from immune checkpoint inhibitor treatment. However, mainstream initiation of immune checkpoint therapy to treat cancers is obstructed by the low response rate and immune-related adverse events in some cancer patients. This has given rise to the need for developing sets of biomarkers that predict the response to immune checkpoint blockade and immune-related adverse events. In this review, we discuss different predictive biomarkers for anti-PD-1/PD-L1 and anti-CTLA-4 inhibitors, including immune cells, PD-L1 overexpression, neoantigens, and genetic and epigenetic signatures. Potential approaches for further developing highly reliable predictive biomarkers should facilitate patient selection for and decision-making related to immune checkpoint inhibitor-based therapies.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.1
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• pp.2-8
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• 2021

Dimethachlor is a synthetic herbicide, belonging to the chloroacetanilide group, that inhibits the undesirable growth of weeds via the suppression of very long-chain fatty acid synthesis. Although dimethachlor has been shown to run off from agricultural fields into aquatic ecosystems, the toxicity of dimethachlor on aquatic invertebrates and vertebrates is unknown. In our study, we assessed the toxicity of dimethachlor on developing zebrafish embryos by analyzing viability, hatching ability, and phenotypic changes. Embryonic viability decreased from 48 h post-fertilization (hpf) at the highest concentration of dimethachlor. Decreased hatching ratio, shortened body length, and pathological changes in the eye, heart, and yolk sac were observed at sub-lethal concentrations. Additionally, dimethachlor increased the number of apoptotic cells and level of reactive oxygen species 120 hpf. Our results indicate that dimethachlor may act as an anti-developmental toxicant when accumulated in an aquatic environment.

• Animal cells and systems
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• v.13 no.2
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• pp.133-139
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• 2009

Green tea seed was extracted with absolute ethanol,and the green tea seed extract(GTSE)was subjected to assays for toxicity, antioxidant ability, angiogenesis inhibitory effects and cell adhesion, as well as western blotting, and an in vivo experiment against 4 high-ranking adult cancers in Korea. Our series of experimental data demonstrated that GTSE has an antioxidant ability superior to that of EGCG in the green tea leaf, and also exhibits a profound high tumor growth inhibitory activity on a variety of cancer cell lines, as well as nude mice infected with cancer cells. GTSE was identified as a natural anticancer compound showing excellent angiogenesis inhibition and cancer cell suppression abilities. Our preliminary observations also indicate that GTSE may be another potential source of natural dietary antioxidants and also may be applicable as a novel natural anticancer agent.

• The Plant Pathology Journal
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• v.39 no.1
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• pp.39-51
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• 2023

Common bean (Phaseolus vulgaris L.) is one of the most important crops in human food production. The occurrence of diseases, such as white mold, caused by Sclerotinia sclerotiorum can limit the production of this legume. The use of Trichoderma has become an important strategy in the suppression of this disease. The aim of the present study was to evaluate the effect of volatile organic compounds (VOCs) emitted by Trichoderma azevedoi CEN1241 in five different growth periods on the severity of white mold in common bean. The in vitro assays were carried out in double-plate and split-plate, and the in vivo assays, through the exposure of the mycelia of S. sclerotiorum to the VOCs of T. azevedoi CEN1241 and subsequent inoculation in bean plants. Chemical analysis by gas chromatography coupled to mass spectrometry detected 37 VOCs produced by T. azevedoi CEN1241, covering six major chemical classes. The profile of VOCs produced by T. azevedoi CEN1241 varied according to colony age and was shown to be related to the ability of the biocontrol agent to suppress S. sclerotiorum. T. azevedoi CEN1241 VOCs reduced the size of S. sclerotiorum lesions on bean fragments in vitro and reduced disease severity in a greenhouse. This study demonstrated in a more applied way that the mechanism of antibiosis through the production of volatile compounds exerted by Trichoderma can complement other mechanisms, such as parasitism and competition, thus contributing to a better efficiency in the control of white mold in bean plants.

• International Journal of Molecular Medicine
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• v.44 no.5
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• pp.1641-1652
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• 2019

Conditioned media from various sources comprise numerous growth factors and cytokines and are known to promote the regeneration of damaged tissues. Among these, natural killer cell conditioned medium (NK-CdM) has been shown to stimulate collagen synthesis and the migration of fibroblasts during the wound healing process. With a long-term aim of developing a treatment for skin photoaging, the ability of NK-CdM to prevent ultraviolet-B (UV-B) damage was assessed in neonatal human dermal fibroblasts (NHDFs) and an in vitro reconstructed skin model. The factors present in NK-CdM were profiled using an antibody array analysis. Protein and mRNA levels in UV-B exposed NHDFs treated with NK-CdM were measured by western blotting and quantitative reverse transcription-PCR, respectively. The total antioxidant capacity of NK-CdM was determined to assess its ability to suppress reactive oxygen species. The anti-photoaging effect of NK-CdM was also assessed in a 3D reconstituted human full skin model. NK-CdM induced proliferation of UV-B-treated NHDFs, increased procollagen expression, and decreased matrix metalloproteinase (MMP)-1 expression. NK-CdM also exhibited a potent antioxidant activity as measured by the total antioxidant capacity. NK-CdM inhibited UV-B-induced collagen degradation by inactivating MAPK signaling. NK-CdM also elicited potential anti-wrinkle effects by inhibiting the UV-B-induced increase in MMP-1 expression levels in a 3D reconstituted human full skin model. Taken together, the suppression of both UV-B-induced MMP-1 expression and JNK activation by NK-CdM suggests NK-CdM as a possible candidate anti-skin aging agent.