• Journal of Microbiology
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• v.39 no.4
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• pp.254-264
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• 2001

Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.

• The Korean Journal of Soil Zoology
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• v.3 no.1
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• pp.19-24
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• 1998

The importance of the gut microorganism in the termite, Reticulitermes Speratus kyushuenesis Morimoto, was estimated by feeding with several antibiotics. Antibiotics which killed the bacterium, but not the fungi (Ampicillin, Kanamycin, Erythromycin), or killed both the microorganismw (Cephaloridine, Tetracycline) reduced the life span of the termite from 245 days to about 15 days. On the other hand, some antibiotics, penicillin and pimaricin, did not greatly reduce the life span of the termite.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.100-116
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• 2002

There are several purpose to introduce microorganism into the Soil. The major purpose is to promote plant growth and inhibit plant pathogens. The model example is to put in nitrogen fixing symbiotic bacteria, Pythium and Rhizobium. In order to achieve the intended goal, the introduced microorganism should survive and colonize with sufficient density. The survival of introduced microorganism depend upon biotic and abiotic factors. Predation and competition are important among biotic factor. Water tension, organic carbon, inorganic nutrients(N, P), pH are important factor among abiootic factor. Soil texture and distribution of soil pore are also important in the survival and colonization of introduced microorganism. Selection by soil ecosystem for inoculant is a crucial factor for colonization. Good example are control of autochtonous microorganism and the introduction of surfactant biodegrading Pseudomonas. Sometimes, carriers such as peat and montmorillonite can be added to help colonization. Carriers can protect introduced microorganism by supplying protective microhabitat. Organic polymer is also used as a carrier to immobilize bacteria or industrial enzymes. Examples of these carrier are calcium alginate, agarose and k-carrageenan. The function of these carrier is to provide microhabitat and help colonization for introduced microorganism.

• Korean Journal of Pharmacognosy
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• v.41 no.1
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• pp.43-47
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• 2010

In order to screen new receptor tyrosine kinase inhibitor which is expected to be anticancer drug lead, we have investigated receptor tyrosine kinase inhibitory activity on the marine alga-derived symbiotic microorganisms (500 strains). The significant activities (over 70% inhibition at $10\;{\mu}g/ml$) were observed in the extracts of ten strains (Strain No.: MFA018, 019, 206, 242, 325, 335, 343, 344, 354, 356), isolated from marine red algae, five strains (Strain No.: MFA030, 126, 213, 324, 339), isolated from the brown algae, and one strain (Strain No.: MFA272), isolated from the marine green algae, respectively. Among the active strains, MFA019 and 356 showed strong receptor tyrosine kinase inhibitory activity with $IC_{50}$ values of 0.6 and $0.9\;{\mu}g/ml$, respectively.

• Korean Journal of Pharmacognosy
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• v.42 no.4
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• pp.354-360
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• 2011

In order to screen new allogeneic mixed lymphocyte culture (allo-MLR) inhibitor which is expected to be immunomodulating drug lead, we have investigated allo-MLR inhibitory activity on the marine-derived symbiotic microorganisms (1,895 strains) from the marine algae. The potent inhibitory activities (over 45% inhibition of proliferation at 10 and 2 ${\mu}g/ml$) without cytotoxicity were observed in the extracts of 46 strains. While, the significant stimulating activities (over 100% proliferation at 10 and 2 ${\mu}g/ml$) without cytotoxicity were observed in the extracts of 5 strains. In the second assay using 46 bioactive strains, 14 strains exhibited again significant allo-MLR inhibitory activity. Finally, 11 strains among the 14 strains inhibited proliferation and IFN-${\gamma}$ production of CD4+ T cells during the stimulation with specific antigen in the third assay. On the basis of above results, the marine algae is nice source for isolation of immunomodulating microorganism, and the marine algae-associated microorganism is also nice target for development of the new immunomodulating drug lead.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.155-173
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• 2011

Humans have and hold 100 trillion intestinal bacteria that are essential for health. For millions of years human-microorganisms interaction has co-evolved, and maintained close symbiotic relationship. Gut bacteria contributes to human health and metabolism, and humans provides the optimum nutrition-rich environment for bacteria. What is the mechanism of the host distinguishing the intestinal bacteria as its cohabiting partner and what kind of benefits does the gut microbiota provide the human are the fundamental questions to be asked and solved in order to make human life a higher quality. This review explains the physiological relationship and mutualism between the host and gut microorganism, and highlights the potential therapeutic approach for treating diseases, maintaining and improving health based on these correlations.

• IMMUNE NETWORK
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• v.12 no.4
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• pp.129-138
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• 2012

Allergic disorders such as atopic dermatitis and asthma are common hyper-immune disorders in industrialized countries. Along with genetic association, environmental factors and gut microbiota have been suggested as major triggering factors for the development of atopic dermatitis. Numerous studies support the association of hygiene hypothesis in allergic immune disorders that a lack of early childhood exposure to diverse microorganism increases susceptibility to allergic diseases. Among the symbiotic microorganisms (e.g. gut flora or probiotics), probiotics confer health benefits through multiple action mechanisms including modification of immune response in gut associated lymphoid tissue (GALT). Although many human clinical trials and mouse studies demonstrated the beneficial effects of probiotics in diverse immune disorders, this effect is strain specific and needs to apply specific probiotics for specific allergic diseases. Herein, we briefly review the diverse functions and regulation mechanisms of probiotics in diverse disorders.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.88-88
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• 1995

Microorganism are centIal core to biosphere sm1ainablity and biogeochemical cycles on this earth. Most of food, medical and pabamceutical new materials through biotechnology are derived from many kinds of microorganisms. Microorganisms are important resources of biotechnology. Beside these, micorbial diversity is key to explore the frontiers of knowledge about the strategies and limits of life. Through the micorotganisms, we can monitor the environmental changes and conditions. Moreover, the microorganismsms play a role in conservation and restoration of higher plants and animals. And we can get a lot of ecological, evolutionary knowledges from microbial models. In spite of these importances, the microbial diversity is not properly evaluted because of their unculturablity. Only 0.001 - 3 % of total bacteria in natural habitats are cultumble and the rest are viable but uncultumble. Only 3,100 species are listed up in the Bergey's Manual. Considering the symbisis and estimated numbers of insect are more than 800,000, the symbiotic microorganisms are about 1,000,000 species. Recently, by using the genetic and molecular technics, the microbial diversity is now unveiled. In this symposium, the genetic, species and ecological diversity will be given. given.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.303-311
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• 2007

From the course of screening of useful xylanase producing microorganism from a phytophagous longicorn beetle, we isolated an extra-cellular xylanase producing strain, Paenibacillus sp. HY-8 from the intestine of Moechotypa diphysis adult. On the basis of morphological, biochemical and phylogenetic studies of the new isolate was identified as a Paenibacillus species. Production of xylanase in this strain was strongly induced by adding xylan to the growth medium and repressed by glucose or xylose. The highest xylanase production was attained in the M9 media containing 1% yeast extract and 0.5% birchwood xylan when cultured at $25^{\circ}C$ for 24 hrs. HY-8 producing xylanase showed superior hydrolytic activities against various plant source feedstuff than control xylanase produced by Tricoderma sp. at pH 6.0.

• Mycobiology
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• v.49 no.3
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• pp.235-248
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• 2021

This study aimed to understand whether the geo-ecological segregation of native plant species affects the root-associated fungal community. Rhizoplane (RP) and rhizosphere (RS) fungal microbiota of Sedum takesimense native to three geographically segregated coastal regions (volcanic ocean islands) were analyzed using culture-independent methods: 568,507 quality sequences, 1399 operational taxonomic units, five phyla, and 181 genera were obtained. Across all regions, significant differences in the phyla distribution and ratio were confirmed. The Chao's richness value was greater for RS than for RP, and this variance coincided with the number of genera. In contrast, the dominance of specific genera in the RS (Simpson value) was lower than the RP at all sites. The taxonomic identity of most fungal species (95%) closely interacting with the common host plant was different. Meanwhile, a considerable number of RP only residing fungal genera were thought to have close interdependency on their host halophyte. Among these, Metarhizium was the sole genus common to all sites. These suggest that the relationship between potential symbiotic fungi and their host halophyte species evolved with a regional dependency, in the same halophyte species, and of the same natural habitat (volcanic islands); further, the fungal community differenced in distinct geographical regions. Importantly, geographical segregation should be accounted for in national culture collections, based on taxonomical uniqueness.