• Biomedical Science Letters
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• v.24 no.4
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• pp.292-304
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• 2018

Microbes is becoming increasingly forensic possibility as a consequence of advances in massive parallel sequencing (MPS) and bioinformatics. Human DNA typing is the best identifier, but it is not always possible to extract a full DNA profile namely its degradation and low copy number, and it may have limitations for identical twins. To overcome these unsatisfactory limitations, forensic potential for bacteria found in evidence could be used to differentiate individuals. Prokaryotic cells have a cell wall that better protects the bacterial nucleoid compared to the cell membrane of eukaryotic cells. Humans have an extremely diverse microbiome that may prove useful in determining human identity and may even be possible to link the microbes to the person responsible for them. Microbial composition within the human microbiome varies across individuals. Therefore, MPS of human microbiome could be used to identify biological samples from the different individuals, specifically for twins and other cases where standard DNA typing doses not provide satisfactory results due to degradation of human DNA. Microbial forensics is a new discipline combining forensic science and microbiology, which can not to replace current STR analysis methods used for human identification but to be complementary. Among the fields of microbial forensics, this paper will briefly describe information on the current status of microbiome research such as metagenomic code, salivary microbiome, pubic hair microbiome, microbes as indicators of body fluids, soils microbes as forensic indicator, and review microbial forensics as the feasibility of microbiome-based human identification.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1659-1676
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• 2002

Ruminant animals develop a diverse and sophisticated microbial ecosystem for digesting fibrous feedstuffs. Plant cell walls are complex and their structures are not fully understood, but it is generally believed that the chemical properties of some plant cell wall compounds and the cross-linked three-dimensional matrix of polysaccharides, lignin and phenolic compounds limit digestion of cell wall polysaccharides by ruminal microbes. Three adaptive strategies have been identified in the ruminal ecosystem for degrading plant cell walls: production of the full slate of enzymes required to cleave the numerous bonds within cell walls; attachment and colonization of feed particles; and synergetic interactions among ruminal species. Nonetheless, digestion of fibrous feeds remains incomplete, and numerous research attempts have been made to increase this extent of digestion. Exogenous fibrolytic enzymes (EFE) have been used successfully in monogastric animal production for some time. The possibility of adapting EFE as feed additives for ruminants is under intensive study. To date, animal responses to EFE supplements have varied greatly due to differences in enzyme source, application method, and types of diets and livestock. Currently available information suggests delivery of EFE by applying them to feed offers the best chance to increase ruminal digestion. The general tendency of EFE to increase rate, but not extent, of fibre digestion indicates that the products currently on the market for ruminants may not be introducing novel enzyme activities into the rumen. Recent research suggests that cleavage of esterified linkages (e.g., acetylesterase, ferulic acid esterase) within the plant cell wall matrix may be the key to increasing the extent of cell wall digestion in the rumen. Thus, a crucial ingredient in an effective enzyme additive for ruminants may be an as yet undetermined esterase that may not be included, quantified or listed in the majority of available enzyme preparations. Identifying these pivotal enzyme(s) and using biotechnology to enhance their production is necessary for long term improvements in feed digestion using EFE. Pretreating fibrous feeds with alkali in addition to EFE also shows promise for improving the efficacy of enzyme supplements.

• Journal of Ginseng Research
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• v.25 no.1
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• pp.53-58
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• 2001

To clarify a significant difference between red-colored phenomena (RCP) and microbes isolated from rhizosphere soil of healthy ginseng (HES) and red-colored ginseng (RCS), we have examined growth and cellulase activities of the microbes according to pH variation and iron status. The soil microbes could not grow at pH 3.0 on the YEB medium. The growth of bacterium isolated from RCG at pH from 5.0 to 9.0 showed small differences and the growth of bacterium HES was lower than that of others. The growth of bacteria from RCS and surface soil (SUS) at pH 5.0 were also lower than that of pH 7.0 and pH 9.0. However, the bacteria isolated from red-colored ginseng (RCG) and RCS are able to grow on the medium contained 2 mM Fe$\^$3+/ at pH 3.0. Furthermore, the growth of bacterium from RCG increased about two times in the medium contained iron at pH 7.0 compared with minus iron. The cellulase activity of isolated bacteria increased two times in the medium contained 2 mM Fe$\^$3+/ compared with minus iron. The activity of extra-cellular cellulase was higher by one hundred times than that of intracellular level. The cellulase activity of the bacterium from RCS at pH 5.0 was higher by two times than that of pH 7.0. Especially, intracellular activity of the bacterium from RCS on the medium contained 2mM Fe$\^$3+/ increased about six to seven times compared with control (minus iron). Also, extra-cellular activity increased about eleven to twelve times compared with control. These results indicate that the soil microbes seem to be related iron redoxidation by proton extrusion and with cell wall digestion by secreted cellulase.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.18-21
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• 2004

The root hair provides a major entering spot for the symbiotic legume rhizobia. It is obvious that dynamic cell wall modification occurs in the plant root hair during the early microbe invasion. Expansins are nondestructive cell wall-modifying proteins that are involved in cell growth and differentiation. Among about 40 expansin genes in Arabidopsis, two expansin genes are expressed specifically in the root hair cell. Orthologous genes of this Arabidopsis root hair expansins have been found in other Brassica members, rice, and Medicago truncatula (a legume). In this review, I discuss the probable function of expansins during the early symbiotic process between the root hair and microbes and the regulation of root hair expansin genes in a comparative approach.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.600-605
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• 1998

Present study was investigate to evaluate the aluminum absorption effect on lactic acid bacteria(Lactobacillus acidophilus ATTC 4356, Lactogacillus bulgaricus ATTC 11842, Lactobacillus casei IFO 3533, and Streptococcus thermophilus KCTC 2185 ; LAB) and Clostridium perfringens ATCC 3627 (CP) in artificial intestinal tract. Their growth rate, aluminum accumulation and cellular distribution was studied under anaerobic broth system. All of above microbes were inhibited by adding 10 to 100ppm of aluminum. The degree of aluminum in LAB (Lactobacillus acidophilus ATCC 4356, Lactobacillus bulgaricus ATCC 11842, Lactobacillus casei IFO 3533, and Streptococcus thermophilus KCTC 2185) was higher than of CP. The largest amount of aluminum was accumulated in Lactobacillus bulgaricus ATCC 11842. Aluminum accumulation in LAB was distributed in 49.1% at cell wall, 27.3% at plasma membrane, and 23.6% at cytoplasm, respectively. This study suggests that LAB might help to eliminate the ingested aluminum in intestinal tract.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1338-1348
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• 2019

The Geomunoreum Lava Tube System, declared as a UNESCO World Heritage Site, has a unique natural ecosystem. The information available about this ecosystem, which contains lava caves with secondary carbonate speleothems, is sparse. Hence, extensive research is warranted for establishing a conservation standard. We commenced microbial research on the system and have been studying the microorganisms coating the lava tube wall to acquire fundamental information for understanding the lava cave ecology of Jeju Island. Samples were collected from yellow-colored walls in six caves that are part of the system-the Bengdwi, Utsanjeon, Bukoreum, Manjang, Gimnyeong, and Yongcheon caves. This study focused on yellow walls as it is the most easily distinguished color. According to previous studies, the color of cave walls is attributed to microorganisms or their components. To determine whether the yellow mats from the Jeju lava tube walls are caused by microorganisms, we examined samples at the microscopic scale, by staining mats and analyzing bacterial isolates from glitter particles. As a result, we found that the yellow walls of lava tubes are comprised of microbial mats.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.129-138
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• 1999

If rumen bacteria can be manipulated to utilize nutrients (i.e., ammonia and plant cell wall carbohydrates) more completely and efficiently, the need for protein supplementation can be reduced or eliminated and the digestion of fiber in forage or agricultural residue-based diets could be enhanced. However, these approaches require a complete and accurate description of the rumen community, as well as methods for the rapid and accurate detection of microbial density, diversity, phylogeny, and gene expression. Molecular ecology techniques based on small subunit (SSU) rRNA sequences, nucleic acid probes and the polymerase chain reaction (PCR) can potentially provide a complete description of the microbial ecology of the rumen of ruminant animals. The development of these molecular tools will result in greater insights into community structure and activity of gut microbial ecosystems in relation to functional interactions between different bacteria, spatial and temporal relationships between different microorganisms and between microorganisms and reed panicles. Molecular approaches based on SSU rRNA serve to evaluate the presence of specific sequences in the community and provide a link between knowledge obtained from pure cultures and the microbial populations they represent in the rumen. The successful development and application of these methods promises to provide opportunities to link distribution and identity of gastrointestinal microbes in their natural environment with their genetic potential and in situ activities. The use of approaches for assessing pupulation dynamics as well as for assessing community functionality will result in an increased understanding and a complete description of the gastrointestinal communities of production animals fed under different dietary regimes, and lead to new strategies for improving animal growth.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.3
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• pp.99-106
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• 1986

This study was carried out to investigate the effects of moisture content, temperature, C/N ratio and pH of the sewage sludge mixed with hulle and sawdusts for making compost under aerobic condition and to improve the defect of the structure of experimental equipment heat lose and handling method. and obtained results were as follows 1.The temperature was reached 73$^{\circ}$ C around 50 hours fermentation in the condition of 0.8 L/min. of air and 60.4% of moisture content. and favorable moisture content of initial condition ranged from 50 to 65% 2.The temperature near bottom of the batch composter was decreased due to evaporate water vapor and lose the heat produced during aeration. and it is required to be improved. 3.The temperature in the batch composter from the center to the inside wall surface was gradually decreased. the temperatures of the points located in r=9cm and the wall surface were 4$^{\circ}$ C and 6$^{\circ}$ C respectively. and therefore it is required to be insulated. 4. The maximum C02 production was obtained as 7.3% per volume in the temperature of 63$^{\circ}$C at the moisture content of 60% 5.The temperature range of active microbes growth was found to be as 20$^{\circ}$C to 40$^{\circ}$C in the case of mesophiles and 50$^{\circ}$C to 65$^{\circ}$C in the case of thermophiles due to increase and decrease C02 production. 6.C/N ratio after decomposition was 1.3 to 2.6 smaller than that of initial one due to increase the amount of nitrogen. The more C/N ratio increased. the less the reaction velocity decresed. The optimum of it as found to be 30. 7.pH values after decomposition were slightly increased than that of initial ones. The reaction velocity was decreased at acid and alkall condition. Therefore it is neseseary to neutralize the medium to improve the reaction.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.417-425
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• 2019

Biocontrol agents (BCAs) are widely used to protect plants from diverse biotic and abiotic stresses in agricultural and ecological fields. Among the various microbes, many subspecies of the gram-positive genus, Bacillus, have been successfully industrialized as eco-friendly biological pesticides and fertilizers. In the current study, we demonstrated that Bacillus thuringiensis C25 exhibited antagonistic effects on the mycelial growth of Rosellinia necatrix, a fungal phytopathogen. Scanning electron microscopy analysis revealed that B. thuringiensis C25 degraded the cell wall structures of R. necatrix mycelia. In the functional genomic analysis of B. thuringiensis C25, we annotated 5,683 genes and selected the gene sets that potentially encoded fungal cell wall degrading enzymes (CWDEs). The growth inhibition effects on R. necatrix were highly correlated with the transcriptional activity of the mycelial cell wall degrading genes of B. thuringiensis C25. The transcript levels of CWDEs, including CshiA, B, and Glycos_transf_2 genes in B. thuringiensis C25, were enhanced following co-cultivation with R. necatrix. In conclusion, our study suggested that B. thuringiensis C25 could serve as a suitable candidate for controlling R. necatrix and could facilitate elucidating the mechanisms underlying the antifungal activities of BCAs against phytopathogens.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.96-114
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• 2000

Genetically selected beef cattle are fed high-energy diets in intensive production systems developed in industrial countries. This type of feeding can induce rumen dysfunctions that have to be corrected by farmers to optimise cost-effectiveness. The risk of rumen acidosis can be reduced by using slowly degradable starch, which partly escapes rumen fermentation and goes on to be digested in the small intestine. Additives are proposed to stabilise the rumen pH and restrict lactate accumulation, thus favouring the growth of cellulolytic bacteria and stimulating the digestion of the dietary plant cell wall fraction. This enhances the energy value of feeds when animals are fed maize silage for example. Supplementation of lipids to increase energy intake is known to influence the population of rumen protozoa and some associated rumen functions such as cellulolysis and proteolysis. The end products of rumen fermentation are also changed. Lipolysis and hydrogenation by rumen microbes alter the form of fatty acids supplied to animals. This effect is discussed in relation with the quality of lipids in beef and the implications for human health. Conditions for optimising the amount of amino acids from microbial proteins and dietary by-pass proteins flowing to the duodenum of ruminants, and their impact on beef production, are also examined.