• Korean Journal of Soil Science and Fertilizer
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• v.42 no.2
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• pp.139-143
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• 2009

We examined the vertical distribution of specific microbial groups and the patterns of microbial community structure within the soil profile using phospholipid fatty acid (PLFA). Samples were collected from the soil surface down to 15 cm in depth from paddy and upland fields located in Daegu, Korea. The two fields have been fertilized with only chemical fertilizers N, P, K for 33 years. Principal component analysis of the PLFA signatures indicated that the composition of the soil microbial communities changed significantly with the cultivation practices and soil depth, suggesting that cultivation practices of paddy and upland fields had more significant influence on soil microbial community than the soil depth did. The soil microbial communities changed more drastically with soil depth in upland field than in paddy field, with making thicker soil surface in paddy field in terms of soil microbial community. The ratios of cyclopropyl/monoenoic precursors and total saturated/total monounsaturated fatty acids increased with soil depth, suggesting that the deeper soil horizons are more carbon-limited and anaerobic than surface soil. The community analysis using PLFAs as biomarkers revealed that Gram-positive bacteria and actinomycetes tended to increase in proportional abundance with increasing soil depth, while the abundance of Gram-negative bacteria and fungi were highest at the soil surface and substantially lower in the subsurface.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.270-276
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• 2005

This study was conducted to examine whether a specific synthetic metalworking fluid (MWF), "A", in use for 10 months without replacement, displayed microbial resistance and to identify the additives associated with the control of microbial growth. Three synthetic MWF products ("A", "B", and "C") were studied every week for two months. Microbial deterioration of the fluids was assessed through evaluation by endotoxin, bacteria and fungi levels in the MWFs. In addition, formaldehyde, boron, ethanolamine, and copper levels were also studied to determine whether they influence microbial growth in water-based MWFs. Throughout the entire study in the sump where MWF "A" was used, bacteria counts were lower than 103 CFU/mL, and endotoxins never exceeded 103 EU/mL. These levels were significantly lower than levels observed in sumps badly deteriorated with microbes. Boron levels in MWF "A" ranged from 91.7 to 129.6 ppm, which was significantly higher than boron levels found in other MWF products. The total level of ethanolamine (EA) in MWF "A" ranged from 35,595 to 57,857 ppm (average 40,903 ppm), which was over ten times higher than that found in other MWFs. Monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA) concentrations in MWF "A" were also significantly higher than seen in other MWFs. However, although EA and boron might improve anti-microbial performance, their abuse can pose a serious risk to workers who handle MWFs. From an industrial hygiene perspective, our study results stress that the positive synergistic effect of boron and EA in reducing microbial activity in MWF must be balanced with the potentially negative health effects of such additives. Our study also addresses the disadvantage of failing to comprehensively report MWF additives on Material Safety Data Sheets (MSDS). Future research in MWF formulation is needed to find the best level of EA and boron for achieving optimal synergistic anti-microbial effects while minimizing employee health hazards.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.167-171
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• 1994

With a view to improving microbiological quality of spinach powder which is currently used for convenience food production, comparative efficacy of ethylene oxide(EO) fumigation and gamma irradiation was investigated by determining microbial populations and physicochemical quality for treated samples. Spinach powder was contaminated with various microorganisms ranging from $10^{2}/g\;to\;10^{4}/g$, which composed of thermophiles, acid tolerant bacteria, fungi, coliforms, etc. Microorganisms contaminated were destroyed up to undetected levels by gamma irradiation at below 7 kGy. showing the radiosensitivity $D_{10}$ 2.93 kGy on total aerobic bacteria. Ethylene oxide fumigation, however. was found unsatisfactory for physicochemical quality as well as microbial decontamination of the sample. It has been generally observed that influence of optimum-dose range of irradiation on the physicochemical qualities was insignificant, which was proved in the organoleptic evaluations on the stored sample.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.25-31
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• 1976

The purpose of this investigation is to find out the effects on the changes of microflora and the effects on the inorganic nutrients of the fertilized soil and the non-fertilized soil under submerged condition with the treatment of butachlor at the levels of 250, 500, and 1000ppm respectively. The survey was made within the period of 72 days with 7-day intervals under the incubated condition. The result came out to be the following: 1. The Fluctuated changes of soil microflora A. Bacteria: The plots treated by 500ppm of butachlor in case of non-fertilized soil showed the decreasing tendency of bacteria until 21st day. But there were no effects on the other plots. The plots treated by 250ppm and 500ppm in case of fertilized soil showed decreasing tendency on the 7th day, and 1000ppm until 21st days. B. Actinomycetes: There was no effects on the actinotnycetes in case of the non-fertilized soil but the fertilized soil showed some decrease. In both cases, actinomycetes have generally shown a little increase according to the time passage. C. Fungi: In both cases of the fertilized soil and the non-fertilized soil, the plots treated by the media showed some decreasing tendency in comparison with the control plots. There was no change to the number of fungi according to the time passage. 2. The fluctuated changes of nutrient A. $NH_4-N$: The whole plots showed decrease of $NH_4-N$ by adding butachlor. The higher the intencity of butachiar showed the more decreasing tendency of $NH_4-N$. In case of the non-fertilized soil, the highest increase of $NH_4-N$ appeared from the 7th day to 14th day, but showed degrease thereafter. The increasing tendency was seen in case of the fertilized soil plots. B. $NO_3-N$: Decrease of $NO_3-N$ was shown in the whole plots by the treatment of media, and on the 44th day of cultivation almost none of $NO_3-N$ was detected. C. $NO_2-N$: Whole plots showed the number of $NO_2-N$ highest on the 35th day, and there were nothing measurable on the 44th day. D. Eh: On the fertilized soil, the condition of reduction went on strongly but on the non-fertilized soil, the condition of reduction kept on till 42nd day and oxidation appeared thereafter.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.872-877
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• 2011

Cultivation of Korea ginseng in newly reclaimed and paddy-converted fields has been increasing, and evaluation of organic amendment effectiveness is needed in the two soil types. Soil organisms influence organic matter decomposition, and their responses to applications of organic matter were studied. De-oiled cake and compost were applied at $20Mg\;ha^{-1}$ and $40Mg\;ha^{-1}$ in both soil types. Changes in microflora were assessed by analyzing phospholipid fatty acid (PLFA). The abundance of nematodes and microarthropods was measured. Microbial PLFA indicators for microorganisms and microarthropod abundance were greater in reclaimed upland than in paddy-converted soil. There were few differences in the microflora and fauna of reclaimed uplands, regardless of treatment. In paddy-converted soil, the abundance of Oribatida was increased by the application of compost at $20Mg\;ha^{-1}$ and was correlated with PLFA indicators of fungi. The results suggested a minimal influence of organic amendments in reclaimed upland, because the organic matter content and abundance of soil organisms are low in mineral soils. In paddy-converted soil, the effects of organic amendment differ among different soil organisms, and soil properties are important mediators of the effect.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.4
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• pp.307-318
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• 2005

This study was conducted to examine effects of brewery meal-based fermented feedstuff supplemented with Aspergillus oryzae(AO) or Saccharomyces cerevisiae(SC) on luminal micro-organism of Korean native cattle. Two cows equipped with luminal cannulas were used as experimental animals. Experiment was done with three treatment groups: $71.5\%$ of commercial feed and $28.5\%$ of com silage(control): $45.0\%$ of commercial feed, $26.5\%$ of fermented feedstuff supplemented with AO and $28.5\%$ of corn silage(TAO): $45.0\%$ of commercial feed, $26.5\%$ of fermented ffedstuff supplemented with SC and $28.5\%$ of corn silage(TSC). The number of total viable bacteria (p<0.05), anaerobic fungi and protozoa(p<0.05) was higher in TAO and TSC than in control. The number of proteolytic bacteria(p<0.05), cellulolytic bacteria and xylan fermenters tended to be higher in TAO and TSC than in control. The dry matter recovery (DMR) of protozoa was higher in TAO and TSC than in control(p<0.05). The crude protein (CP) content of total microbes and protozoa was higher in TSC than in control and TAO (p<0.05). The CP content of bacteria was higher in TAO and TSC than in control(p<0.05). The ether extract(EE) content of the total microbes was higher in TAO than in control and TSC(p<0.05), and the EE of protozoa and bacteria were higher in TSC than in control and TAO(p<0.05). The ratio of essential amino acids of total microbe was higher in control than in TAO and TSC(p<0.05). The ratio of methionine and alanine of bacteria was higher in TAO and TSC than in control(p<0.05). The results suggested that the feeding of fermented feedstuff supplemented with AO or SC had an influence on the numbers of ruminal microorganism and the changes of microbial body composition.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.67-76
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• 1984

This experiment was conducted to find out the changes in microflora of submerged soil uncultivated rice plant by application of CNP herbicide (2, 4, 6 - Trichlorophenyl-4-Nitrophenyl ether) under conditions applied with compost, rice straw, glucose or without organic material. The soil, sandy loam textured was incubated in green house for 66 days. Sampling and analysis of microorganisms were carried out during submergence periods. The results were summarilized as follows. 1. Number of aerobic total bacteria was increased by application of CNP herbicide during submerbed 50 days, afterthen, could not seen the difference. The application of rice straw increased number of aerobic bacteria regardless of CNP herbicide application or not, but glucose tended to decrease. 2. Number of Fungi was constantly maintained at $8-20{\times}10^3$ levels during period of submergence regardless of application of CNP herbicide and organic materials or not. 3. The CNP herbicide application tended to decrease the number of actinomycetes, particularly, in the treatments without organic substances and rice straw were remarkably decreased. 4. Anaerobic-and gram-negative bacteria populations were not showed any difference by application of herbicide and organic materials. 5. The ratios of aerobic bacteria to fungi and aerobic bacteria to actinomycetes appeared high values by application of herbicide and of organic substances. 6. At 66 days after submergence, the ratio of chromogenic actinomycetes to the total number of actinomycetes was lowered in application of herbicide. On the other hand, the percentage of both pretense-positive and cellulase-positive actinomycetes to the total isolates were higher in the treatment with herbicide than An without herbicide, particularly. The ratios of pretense-positive actinomycetes were high in the rice straw application regardless of herbicide application or not, but cellulase-positive actinomycetes was not remarkably difference.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.219-228
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• 2009

The construction procedures and artificial turf maintenance program on golf course definitely influence on the distortion of its environment. Soil microbial communities in soil profile were affected directly by those practises on turf areas. In Jeju island, the environmental impact assessment has been required to apply the first quality class granular activated carbon(GAC), which has a high absorbent character to agricultural chemicals, on the soil profiles of golf green system to reduce the pesticide leaching to ground water. This research was carried out to analyze the changes of microbial communities and chemical properties on soil profiles where GAC had been applied at the construction stage at two golf courses in Jeju. The changes of soil microbial population and chemical properties associated with construction methods of soil profile and agrochemical management program were analyzed by monthly at the surface and sub-soil profiles during April through October, 2007. The total numbers of bacteria and fungi, soil moisture content, soil physio-chemical properties were measured on greens and fairways of the both golf courses with different GAC treatment on the green and fairway soil profiles. The results showed that GAC had positive effects on the water holding capacity, pH and EC, however, it did not improved the holding capacity of available nutrients ${NO_3}^-,{NH_4}^+$, and phosphorus by its sorption phenomenon. In microbial count test, the total numbers of bacteria and fungi showed a great variation during sampling dates. That may directly relate to the agrochemical application, however, the ratio of total bacterial number versus total fungus number showed a constant value on a sub-soil of 15~30cm depth. Thus, the construction method of GAC in soil profile, and application of fertilizer and pesticide, both impacted on the changes of microbial population. It's means that the construction method of soil profile and turf management using agro-materials might greatly affect on the turfgrass culture and the environment of golf course.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1083-1095
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• 2019

Butyrate is known to play a significant role in energy metabolism and regulating genomic activities that influence rumen nutrition utilization and function. Thus, this study investigated the effects of an isolated butyrate-producing bacteria, Clostridium saccharobutylicum, in rumen butyrate production, fermentation parameters and microbial population in Holstein-Friesian cow. An isolated butyrate-producing bacterium from the ruminal fluid of a Holstein-Friesian cow was identified and characterized as Clostridium saccharobutylicum RNAL841125 using 16S rRNA gene sequencing and phylogenetic analyses. The bacterium was evaluated on its effects as supplement on in vitro rumen fermentation and microbial population. Supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum increased (p < 0.05) microbial crude protein, butyrate and total volatile fatty acids concentration but had no significant effect on $NH_3-N$ at 24 h incubation. Butyrate and total VFA concentrations were higher (p < 0.05) in supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum compared with control, with no differences observed for total gas production, $NH_3-N$ and propionate concentration. However, as the inclusion rate (CFU/ml) of C. saccharobutylicum was increased, reduction of rumen fermentation values was observed. Furthermore, butyrate-producing bacteria and Fibrobacter succinogenes population in the rumen increased in response with supplementation of C. saccharobutylicum, while no differences in the population in total bacteria, protozoa and fungi were observed among treatments. Overall, our study suggests that supplementation with $10^6CFU/ml$ C. saccharobutylicum has the potential to improve ruminal fermentation through increased concentrations of butyrate and total volatile fatty acid, and enhanced population of butyrate-producing bacteria and cellulolytic bacteria F. succinogenes.

• Journal of the Korean Society of Tobacco Science
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• v.32 no.1
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• pp.1-11
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• 2010

This study was carried out to investigate the influence of stem materials such as black stem on the quality of expended stem and cigarettes. Normal and black stem were separated by tobacco scan and then, those stems were expanded after treating with their respective stem casings. Total sugar, ether extract, ash contents and pH were slightly low in black stem compared with normal stem. However, the number of bacteria and fungi ratio were remarkably higher in black stem than that of normal stem. As compared with normal stems, ratio of rushed stem in rolled process was approximately 2 times higher in black stem with the consequency that the filling capacity of black stem was decreased. The ratio of large particles (> 3.35 mm) of expanded black stem showed decreasing tendency and small particles rate (1.40 mm <) was increased compared with normal stem. When expanded stems were prepared using stem containing 5 levels (0, 10, 20, 30 and 100 %) of black stem, the filling capacity was decreased and static burning rate was significantly decreased with increasing expanded black stem rate. However, the weight and hardness of cigarettes were slightly increased with increasing expanded black stem rate. The contents of phenol compounds, aromatic amines and carbonyl compounds in the cigarette mainstream smoke from the cigarette which was manufactured with various ratio of expended black stem, were gradually increased with increasing expanded black stem rates. Also, the cytotoxicity and the mutagenicity of the TPM were significantly increased with increasing expanded black stem rate. The sensory test result showed that cigarettes blended with 10 and 30 % level of black stem rate was exhibited significantly high sensory attributions such as off-taste, impact, hotness, bitterness and irritation as compared with cigarette blended with normal stem, while smoke fullness and cleanness were slightly decreased with increasing expanded black stem rates. The number of brown spots on cigarettes paper was 2 to 3 times high in cigarettes containing black stem than that of cigarette made from normal stem and were high with increasing black stem rate. The overall assessment in this study suggest, that black stem should not be used because of bad quality of expanded stem and high toxicological activity of cigarette mainstream smoke.