• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.5
• /
• pp.371-379
• /
• 2018

The lack of seed sludges for Ammonium Oxidizing Bacteria (AOB) and slow-growing ANaerobic AMMonium OXidation (ANAMMOX) bacteria is one of the major problem for large-scale application. In this study, $24m^3$ of single-stage SBR (Sequencing Batch Reactor) was operated to remove nitrogen from reject water using AOB and ANAMMOX bacteria cultivated from activated sludge in the field. The ANAMMOX activity was found after 44 days of cultivation in the ANAMMOX cultivation reactor, and then $0.66kg\;N/m^3/d$ of the nitrogen removal rate was achieved at $0.78kg\;N/m^3/d$ of the nitrogen loading rate at 153 days of cultivation. The AOB cultivation reactor showed $0.2kg\;N/m^3/d$ of nitrite production rate at $0.4kg\;N/m^3/d$ of nitrogen loading rate after 36 days of operation. The cultivated ANAMMOX bacteria and AOB was mixed into the single-stage SBR. The feed distribution was applied to remove total nitrogen stably in the single-stage SBR. The nitrogen removal rate in the single-stage SBR was gradually enhanced with an increase of specific activities of both AOB and ANAMMOX bacteria by showing $0.49kg\;N/m^3/d$ of the nitrogen removal rate at $0.56kg\;N/m^3/d$ of the nitrogen loading rate at 54 days of operation.

• Journal of Microbiology
• /
• v.43 no.3
• /
• pp.219-227
• /
• 2005

Little is known about the bacterial communities associated with the plants inhabiting sand dune ecosystems. In this study, the bacterial populations associated with two major sand dune plant species, Calystegia soldanella (beach morning glory) and Elymus mollis (wild rye), growing along the costal areas in Tae-An, Chungnam Province, were analyzed using a culture-dependent approach. A total of 212 bacteria were isolated from the root and rhizosphere samples of the two plants, and subjected to further analysis. Based on the analysis of the 16S rDNA sequences, all the bacterial isolates were classified into six major phyla of the domain Bacteria. Significant differences were observed between the two plant species, and also between the rhizospheric and root endophytic communities. The isolates from the rhizosphere of the two plant species were assigned to 27 different established genera, and the root endophytic bacteria were assigned to 21. Members of the phylum Gammaproteobacteria, notably the Pseudomonas species, comprised the majority of both the rhizospheric and endophytic bacteria, followed by members of Bacteroidetes and Firmicutes in the rhizosphere and Alphaproteobacteria and Bacteroidetes in the root. A number of isolates were recognized as potentially novel bacterial taxa. Fifteen out of 27 bacterial genera were commonly found in the rhizosphere of both plants, which was comparable to 3 out of 21 common genera in the root, implying the host specificity for endophytic populations. This study of the diversity of culturable rhizospheric and endophytic bacteria has provided the basis for further investigation aimed at the selection of microbes for the facilitation of plant growth.

• Journal of Korean Society on Water Environment
• /
• v.26 no.1
• /
• pp.10-18
• /
• 2010

Water quality and the distribution of ammonia oxidizing bacteria were characterized in constructed wetland of Shihwa lake. Both physico-chemical parameters and fecal indicator microorganisms including total coliforms, E.coli, Enterococcus spp. were measured. In addition, denaturant gradient gel electrophoresis (DGGE) was carried out after PCR amplification of amoA gene from input, output, and wetland sites of the Banwol, Donghwa, and Samhwa stream in Shihwa lake area. Physico-chemical parameters were in proper range for typical nitrifying bacteria to grow and perform their biological activities. Average concentrations of fecal indicator microorganisms of wetland samples were lower than those of input sites. These results suggested that microbial water quality improved by the process of constructed wetland. According to phylogenetic information obtained from DGGE from study sites, distribution of nitrifying bacteria from each of input, output, and wetland were generally distinctive one another. In addition, distribution of nitrifying bacteria between Banwol and Donghwa streams showed higher similarity (52.6%) than this of Samhwa stream (15.2%). These results indicated that characteristics of ammonia oxidizing bacteria in Samhwa were unique in comparison with those of Banwol and Donghwa stream.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.7
• /
• pp.1288-1299
• /
• 2017

Composting is widely used to transform waste into valuable agricultural organic fertilizer. Anaerobic ammonium-oxidizing (anammox) bacteria play an important role in the global nitrogen cycle, but their role in composting remains poorly understood. In the present study, the community structure, diversity, and abundance of anammox bacteria were analyzed using cloning and sequencing methods by targeting the 16S rRNA gene and the hydrazine oxidase gene (hzo) in samples isolated from compost produced from cow manure and rice straw. A total of 25 operational taxonomic units were classified based on 16S rRNA gene clone libraries, and 14 operational taxonomic units were classified based on hzo gene clone libraries. The phylogenetic tree analysis of the 16S rRNA gene and deduced HZO protein sequences from the corresponding encoding genes indicated that the majority of the obtained clones were related to the known anammox bacteria Candidatus "Brocadia," Candidatus "Kuenenia," and Candidatus "Scalindua." The abundances of anammox bacteria were determined by quantitative PCR, and between $2.13{\times}10^5$ and $1.15{\times}10^6$ 16S rRNA gene copies per gram of compost were found. This study provides the first demonstration of the existence of anammox bacteria with limited diversity in cow manure composting.

• Korean Journal of Microbiology
• /
• v.36 no.3
• /
• pp.167-172
• /
• 2000

Twenty-five halotolerant gram-positlve bacteria were isolated from the coastal seawater 01 Cheju Island and Incheon J&yakdo Chemosystematic and phenotypic characteristics were used to iuvestigate the taxonomic position of these bacteria. According to their chemosystematic characteristics, the twenty-tive isolates were divided into 4 groups. Group 1 bacteria possesed 40.1 to 49.9 inol% m DNA G+C content, menaquinone-7 as a major quinone, and meso-Alpm as a diamino acid of peptidoglycan. Group 1 tam were identified as Bacilluspumilis, Bacillus lichenifbrrizis, Bacillus megaterium, Bncill~rsubtilis. Group 2 bacteria possessed 63.9 to 66.4 mol% and MK-8. They were all in the genus Arth~obaclm-. Group 3 bacteria possessed 31.0 to 37.6 mol% and MK-7. They were identified as Staphylococcus haeniol.viicvs, Siaph~~lococc~is sapropl~j~ticns, and Siaphylococcus intermediru.. Group 4 bacterium possessed 72.0mol% and MK-8 and was identified as ~Lficrococcus ltdtezm. Bacillus species accounted for 68% of h e total isolates.

• Food Engineering Progress
• /
• v.13 no.4
• /
• pp.352-359
• /
• 2009

Lactic acid bacteria was isolated for the production of probiotic animal feed supplemented with garlic and its antimicrobial properties were investigated. A total of 112 strains of lactic acid bacteria which grew on the medium containing garlic extract were isolated from kimchi, jeotgal, and jangachi. Among them 14 strains were tested for acidand bile salt-resistance as well as antimicrobial activities against animal pathogenic bacteria such as Salmonella choleraesuis, Escherichia coli, Staphylococcus aureus, and Shigella flexneri. Of these strains, a strain P'GW50-2 from pickled scallion with most desirable properties was selected and identified as Lactobacillus plantarum TJ-LP-002. Antimicrobial activity of L. plantarum TJ-LP-002 showed relatively wide range of inhibition spectrum against Gram negative bacteria such as Aeromicrobium hydrophila, E. coli, Pseudomonas, Salmonella, Shigella, and some Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus, Clostridium perfringens, and Propionibacterium.

• Journal of Food Hygiene and Safety
• /
• v.26 no.2
• /
• pp.182-185
• /
• 2011

This study was conducted to develop an appropriated management for safety of children snacks sold around school. Total 598 items as targeted food were collected; 66 biscuits, 320 candies, 57 chocolates, 40 ice creams and 115 beverages. Microbiological hazards such as total aerobic bacteria, Coliforms, Escherichia coli, Bacillus ceruse, Yeasts & molds were measured by analytical method in Korean food code. Total aerobic bacteria and Yeasts & molds were detected in cookies at the level of less than 2.69 and 2.65 $log_{10}$ CFU/g and the detection rates were 54.55 and 62.12%, respectively. Bacillus cereus was detected in 1 snack only at the level of 1.39 $log_{10}$ CFU/g but it was less than Korean microbial standards and specifications (3 $log_{10}$ CFU/g). Total aerobic bacteria and Yeasts & molds were detected in candies less than 2.86, 3.36 $log_{10}$ CFU/g and the detection rates were 46,8% respectively. Total aerobic bacteria, Yeast & mold were detected in chocolates at the levels less than 2.52 and 1.87 $log_{10}$ CFU/g and the detection rates were 33 and 22% respectively. Total aerobic bacteria in both ice creams and beverages were detected at the levels less than 3.39 and 1.35 $log_{10}$ CFU/g and the detection rates were 82 and 5% respectively. Coliforms were found in one ice cream (1.39 $log_{10}$ CFU/g) only. The result of this study indicated that all children snacks around school were suitable for microbial standard and specifications in Korean Food Code. However, since most children snacks around school are circulated without proper storage temperature and handing condition, consistent microbial management for children snacks are needed.

• Journal of Animal Science and Technology
• /
• v.59 no.11
• /
• pp.27.1-27.7
• /
• 2017

Background: Cashew nut shell liquid (CNSL) is an agricultural byproduct containing alkylphenols that has been shown to favorably change the rumen fermentation pattern only under experimentally fixed feeding conditions. Investigation of CNSL potency in rumen modulation under a variety of feeding regimens, and evidence leading to the understanding of CNSL action are obviously necessary for further CNSL applications. The objective of this study was to evaluate the potency of CNSL for rumen modulation under different dietary conditions, and to visually demonstrate its surfactant action against selected rumen bacteria. Methods: Batch culture studies were carried out using various diets with 5 different forage to concentrate (F:C) ratios (9:1, 7:3, 5:5. 3:7 and 1:9). Strained rumen fluid was diluted with a buffer and incubated with each diet. Gas and short chain fatty acid (SCFA) profiles were characterized after 18 h incubation at $39^{\circ}C$. Monensin was also evaluated as a reference additive under the same conditions. Four species of rumen bacteria were grown in pure culture and exposed to CNSL to determine their morphological sensitivity to the surfactant action of CNSL. Results: CNSL supplementation decreased total gas production in diets with 5:5 and 3:7 F:C ratios, whereas the F:C ratio alone did not affect any gas production. Methane decrease by CNSL addition was more apparent in diets with 5:5, 3:7, and 1:9 F:C ratios. An interactive effect of CNSL and the F:C ratio was also observed for methane production. CNSL supplementation enhanced propionate production, while total SCFA production was not affected. Monensin decreased methane production but only in a diet with a 1:9 F:C ratio with increased propionate. Studies of pure cultures indicated that CNSL damaged the cell surface of hydrogen- and formate-producing bacteria, but did not change that of propionate-producing bacteria. Conclusion: CNSL can selectively inhibit rumen bacteria through its surfactant action to lead fermentation toward less methane and more propionate production. As CNSL is effective over a wider range of dietary conditions for such modulation of rumen fermentation in comparison with monensin, this new additive candidate might be applied to ruminant animals for various production purposes and at various stages.

• Korean Journal of Soil Science and Fertilizer
• /
• v.29 no.1
• /
• pp.53-59
• /
• 1996

This study was conducted to evaluate the effects of fowl dzopping. saw dust and rice hall on the soil microflora in vitro. The experiment was designed in seven treatments with the various organic materials and they were only soil (control). soil + fowl dropping (S+F), soil+fowl dropping+rice hull (S+F+R) soil+fowl dropping*saw dust (S+F+S). soil+chemical fertilizer (S+C.F), fowl dropping+rice hull (F+R) and fowl dropping+saw dust (F+S). All the samples of treatment were incubated in $28{\pm}2^{\circ}C$ condition and tested the activity of soil microflora for 84 days The activity of fungi, total bacteria, gram-negative bacteria and actinomycetes showed the highest values at, twenty-first day and the spore-forming bacteria was at forty-second day after incubation. The number of fungi and gram-negative bacteria showed the highest values in the treatment of F+S, the spore-forming bacteria and the actinomycetes were in the S+F+S. and the number of total bacteria was in the F+C.F., but in the treatment of F+R. all the microorganism except fungi showed the lowest values in their numbers. The composition ratio of dead bacteria was higher in the treatments of S+F+R and F+R than in those of others as 70% and 40% respectively. Actinomycetes isolated from the treatments of S+F and S+F+S were identified as Streptomyces sp.. Nocardia sp., Micromonospora sp. Actinomadura sp. and Saccharomonospora sp.

• Journal of Life Science
• /
• v.28 no.4
• /
• pp.444-453
• /
• 2018

Barley (Hordeum vulgare L.), of the Poaceae/Gramineae family, is a common grain in the surrounding area. It has been used in Ancient Egyptian medicine and it has been used worldwide for many years as food and as an ingredient in beer. Barley has been reported to have anti-inflammatory, anti -carcinogenic and anti-diabetic effects. So far, a lot of research has been done on barley but the effects of fermented barley seeds with lactic acid bacteria have not been studied largely. In this study, we investigated the effects of ethanol-extracted barley seeds after their fermentation with lactic acid bacteria. The biological activities of fermented barley seeds with lactic acid bacteria and non-fermented barley seeds were analyzed for total polyphenol content, total flavonoid content, DPPH radical scavenging, superoxide dismutase-like activity and tyrosinase inhibition. These results showed that fermented barley seeds with lactic acid bacteria have more advanced anti-oxidant and whitening properties than non-fermented barley seeds. Hence, we suggest that fermenting barley seeds with lactic acid bacteria can be an impressive material in the food and cosmetic industries.