• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1903-1912
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• 2018

Objective: To evaluate the effect of lactic acid bacteria and storage temperature on the microbial, chemical and mycotoxin composition of corn silage. Methods: Corn was harvested at 32.8% dry matter, and chopped to 1 to 2 cm. The chopped material was subjected to three treatments: i) control (distilled water); ii) $1{\times}10^6$ colony forming units (cfu)/g of Lactobacillus plantarum; iii) $1{\times}10^6cfu/g$ of Pediococcus pentosaceus. Treatments in triplicate were ensiled for 55 d at $20^{\circ}C$, $28^{\circ}C$, and $37^{\circ}C$ in 1-L polythene jars following packing to a density of approximately $800kg/m^3$ of fresh matter, respectively. At silo opening, microbial populations, fermentation characteristics, nutritive value and mycotoxins of corn silage were determined. Results: L. plantarum significantly increased yeast number, water soluble carbohydrates, nitrate and deoxynivalenol content, and significantly decreased the ammonia N value in corn silage compared with the control (p<0.05). P. pentosaceus significantly increased lactic acid bacteria and yeast number and content of deoxynivalenol, nivalenol, T-2 toxin and zearalenone, while decreasing mold population and content of nitrate and 3-acetyl-deoxynivalneol in corn silage when stored at $20^{\circ}C$ compared to the control (p<0.05). Storage temperature had a significant effect on deoxynivalenol, nivalenol, ochratoxin A, and zearalenone level in corn silage (p<0.05). Conclusion: Lactobacillus plantarum and Pediococcus pentosaceus did not decrease the contents of mycotoxins or nitrate in corn silage stored at three temperatures.

• 한국유기농업학회지
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• 제23권4호
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• pp.767-779
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• 2015

본 연구에서는 신규 개간지 유기농경지에서 가축분퇴비와 녹비작물을 2년간 연용하였을 때 유기물에 의한 밭 토양미생물 군집에 미치는 영향을 평가하고자 수행하였다. 가축분 퇴비와 녹비를 연용한 처리구는 화학비료와 무비 처리구에 비해 유기물 함량이 증가하였다. 세균과 사상균 개체수는 유기물을 연용 할수록 유기물 처리구와 화학비료 그리고 무비 처리구간의 유의적인 차이를 나타내었다. 또한 가축분 퇴비와 녹비 연용으로 토양 미생물체량은 모든 처리구가 증가하였으며 NPK와 무비구에 비해 퇴비, 녹비 처리구에서 높게 나타났다. 유기물 연용에 의한 토양미생물 군집의 기능적 다양성 분석에서 가축분 퇴비, 녹비 처리구가 화학비료나 무비구에 비해 기질 이용도가 유의적으로 증가하였으며 유기물 처리구가 화학비료나 무비구에 비해 높은 종 다양성을 나타냈다. 그리고 주성분 분석에서 제2주성분에 의해 유기물 처리구와 그렇지 않은 화학비료, 무비구로 분리되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.220-228
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• 2007

The nutritive value and the effect of tannins on the utilization of foliage from three commonly used legumes, Acacia nilotica, Albizia procera, and Sesbania acculeata, were determined. Three mature rumen-fistulated bullocks were used to study in sacco degradability and twelve adult sheep were randomly allocated on the basis of live weight to 4 groups of 3 in each to study the in vivo digestibility of the foliages. In all foliages, the contents of crude protein (17 to 24% of DM) were high. Fibre was especially high in Albizia (NDF 58.8% of DM vs. 21% in Sesbania and 15.4% in Acacia). Contents of both hydrolysable (4.4 to 0.05%) and condensed tannins (1.2 to 0.04%) varied from medium to low in the foliages. Acacia contained the highest level of total phenolics (20.1%), protein precipitable phenolics (13.2%) and had the highest capacity to precipitate protein (14.7%). Drying in shade reduced the tannin content in Acacia and Albizia by 48.6 and 69.3% respectively. The foliages ranked similarly for each of the different methods used to estimate tannin content and activity. Acacia and Sesbania foliage was highly degradable (85-87% potential degradability of DM in sacco), compared to Albizia (52%), indicating a minimal effect of tannins in Acacia and Sesbania. Yet, in vitro, the tannins in the Acacia inhibited microbial activity more than those in Albizia and Sesbania. Following the addition of polyethylene glycol to neutralise the tannins, gas production and microbial growth increased by 59% and 0.09 mg RNA equiv./dg microbial yield respectively in the Acacia, compared to 16-17% and 0.06 mg RNA equiv./dg microbial yield in the other foliages. There was a trend for low in vivo apparent digestibility of N in the Acacia (43.2%) and Albizia (44.2%) compared to the Sesbania (54.5%) supplemented groups. This was likely to be due to presence of tannins. Consistent with this was the low N retention (0.22 and 0.19 g N/g NI) in sheep supplemented with Acacia and Albizia compared to that for the Sesbania (0.32). Similarly, a trend for poor microbial N yield was observed in sheep fed these foliages. Across the foliages tested, an increase in tannin content was associated with a reduction in ruminal fermentation, N digestibility and N retention. For overall nutritive value, Sesbania proved to be the superior forage of the three tested.

• 한국조경학회지
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• 제36권3호
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• pp.21-28
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• 2008

토양 유기물 관리는 골프장 그린 관리 중 핵심적인 요소이다. 골프장 그린의 유기물에 대한 지속적인 관리를 연구하는 중요한 프로젝트의 일환으로서, 우리는 동일한 근권부 조성과 관리 하에서 유지되고 있는 서로 다른 조성 시기의 그린들에서 토양 유기물의 상태를 비교하였다. 그리고 그 토양 미생물 활성, 잔디 분얼경수, 용적밀도, 수분함량, pH, EC, 그리고 총질소를 측정하였다. 토심 0${\sim}$5cm에서 토양 유기물 집적은 그린들 간에 유의차를 보이지 않았다. 토심 5cm 이하에서 SOM은 그린들 간에 강한 유의차를 보였고, 경과 연수와 정(+)의 상관을 가졌고 토심과 음(-)의 상관을 가졌다. 토심 5${\sim}$25cm 단층부에서는 시간 경과와 토섬에 따른 SOM의 집적을 예측하기 위해서 회귀 분석한 결과에서 그린의 경과 연수가 증가함에 따라서 유기물 함량이 0.061% year$^{-1}$로 증가하고， 토심이 깊어질수록 유기물 함량이 0.079% cm$^{-1}$로 감소하는 것으로 나타났다. 경과 연도와 토심에 따른 토양 미생물 활성이 탈수소효소 검정을 이용하여 측정되었다. 결과는 모든 그린들에서 토심에 따라서 급격한 감소를 보였다. 토심 5cm 이하에서 토양 미생물 활성은 그린툴 간에 유의차가 없음을 보였다. 집적된 토심 5cm 이하의 SOM은 장기적으로 분해에 대하여 강한 저항성을 가지는 것으로 보인다. 그린 조성 후 5년부터 용적밀도는 유의성 있는 변화를 나타내지 않았다. 수분함량, Ee, 그리고 총질소는 SOM과 유의성 있는 상관을 가지고 있었다. pH는 시간이 경과하며 낮아졌는데, 이것은 SOM 집적에 영향을 미칠 것이다. 유기물 집적은 pH 저하, 미생물 활성 감소 토양 유기물의 분해 저항성 증가 등에 주요하게 영향을 받았지만, 수분 함량, EC, 총질소에 의한 영향은 분명하지 않았다.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.994-1001
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• 2001

An easier way of understanding the BNR system was proposed from the study on substrate, nutrient removal tendency, microbial community and its metabolic function by applying the municipal settled sewage. During the anaerobic period, the phosphorus release rate per VFACOD we varied depending on the phosphorus content in the sludge. When the phosphorus content in the sludge was $6\%$ VSS, according to influent VFACOD, the phosphorus release rate and PHA production were $0.35 gPO_4P/gVFACOD$ and 1.0 gPHA/gVFACOD, respectively. The $NO_3N$ requirement for the phosphorus uptake as an electron acceptor was about $0.5 gNO_3N/gPO_4P_{uptake}$ based on the proposed equation with PHA, biomass, production, and the concentration of phosphorus release/uptake. Bacterial-community analysis of the sludge, as determined by FISH and 16SrDNA characterization FISH, revealed that the beta-subclass proteobacteria were the most abundant group ($27.9\%$ of the proteobacteria-specific probe EUB338), and it was likely that representative of the beta-subclass played key roles in activated sludge. The next dominant group found was the gamma-protebacteria ($15.4\%$ of probe EUB338). 16S rDNA clone library analysis showed that the members of${\beta}$- and ${\gamma}$-proteobacteria were also the most abundant groups, and $21.5\%$ (PN2 and PN4) and $15.4\%$ (PN1 and PN5) of total clones were the genera of denitrifying bacteria and PAO, respectively. Prediction of the microbial community composition was made with phosphorus content (Pv, $\%$ P/VSS) in wasted sludge and profiles of COD, PHA, $PO_4P,\;and\;NO_3N$ in an anaerobic-anoxic SBR unit. Generally, the predicted microbial composition based upon metabolic function, i.e., as measured by stoichiometry, is fairly similar to that measure by the unculturable dependent method. In this study, a proposal was made on he microbial community composition that was more easily approached to analyze the reactor behavior.

• 한국식품과학회지
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• 제52권1호
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• pp.94-102
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• 2020

본 연구는 친환경 현미와 (재)발효미생물산업진흥원에서 보유 중인 알코올 내성이 강하며, 풍미가 좋은 효모를 이용하여 온도조건 및 누룩비율별 품질특성을 진행 후, 막걸리 품질향상 및 제조 표준화에 기여하고자 하였다. 막걸리 제조는 모두 현미 무게 대비 적용비율이며, 증자 후 방랭한 현미에 물 150% (v/w)로 첨가한 다음 누룩 비율 5, 10, 15%를 첨가하고, S. cerevisiae SRCM102596 (8.0±0.10 log¹⁰ CFU/mL)를 모든 시료에 10% (v/w)로 첨가하였다. 발효 온도는 20, 25℃로 5일간 발효를 진행하였다. pH, 총산도는 발효가 진행됨에 pH 범위는 낮아졌으며, 총산도는 높아졌다. 알코올 함량은 발효가 진행됨에 따라 높아졌으며 17.15%까지 나타났다. DPPH radical 소거능과 총 폴리페놀 함량 또한 발효가 진행됨에 따라 소량 증가하였으며, 유리당 함량은 glucose 함량이 가장 높게 나타났고, 발효가 진행됨에 따라 maltose는 감소하였다. 유기산 함량은 lactic acid가 가장 높았으며, succinic acid, acetic acid의 순으로 높았다. 유리아미노산은 총 24종이 검출되었으며, 총 유리아미노산 함량은 20℃ 누룩비율 10% 시료에서 327.50±5.59 mg/L로 가장 높게 나타났다. 감칠맛을 나타내는 glutamic acid는 누룩 5%에서 25℃로 발효된 시료에서 20.98±1.22 mg/L로 가장 높게 나타났으며, 특히 threonine, serine, alanine 함량은 20℃ 누룩비율 10% 시료에서 각각 5.45±0.14, 7.64±0.28, 23.16±3.15 mg/L로 가장 높게 나타났다. 유리아미노산의 구체적인 연구가 진행된다면 막걸리의 차별화 전략에 도움이 될 것으로 생각되며, 막걸리 품질 표준화를 위해서는 더 많은 연구가 필요할 것으로 사료된다.

• Animal Bioscience
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• 제37권1호
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• pp.151-160
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• 2024

Objective: The growing consumers' interest on animal welfare has raised the request of products obtained by alternative rearing systems. The present study was conducted to assess the influence of housing system on gut and muscle morphology and on microbial load in rabbits reared under free-range (FR) and cage system (CS). Methods: A total of forty weaned (35 days of age) male Italian White breed rabbits were allotted according to the rearing system, and at 91 days of age were randomly selected and slaughtered for the morphological evaluation of tissue from duodenum and longissimus lumborum. Morphometric analysis of the villus height, villus width, crypt depth, villus height/crypt depth ratio, and villus surface was performed. The microbial loads on hind muscle was determined by total mesophilic aerobic count (TMAC), Escherichia coli and Enterobacteriaceae; whereas, total anaerobic bacteria count (TABC) and TMAC, E. coli and Enterobacteriaceae was determined on caecal content. Results: Rearing system did not interfere with the duodenum and muscle histomorphology in both rabbit groups. Similarly, microbial load of caecal content showed no significant differences on the TABC and TMAC. Conversely, significant difference was found for E. coli strains in caecal content, with the lower counts in FR compared to CS rabbits (p<0.01). Microbiological assay of muscle revealed significant lower TMAC in FR vs CS rabbits (p< 0.05). All rabbit meat samples were negative for E. Coli and Enterobacteriaceae. Conclusion: Free-range could be considered a possible alternative and sustainable rearing system in rabbits to preserve gut environment and muscle quality.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.133-139
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• 2010

Atmospheric $CO_2$ concentrations have increased exponentially over the last century and, if continued, are expected to have significant effects on plants and soil. In this study, we investigated the effects of elevated $CO_2$ on the growth of Pinus densiflora seedling and microbial activity in soil. Three-year-old pine seedlings were exposed to ambient as well as elevated levels of $CO_2$ (380 and 760 ppmv, respectively). Growth rates and C:N ratios of the pine seedlings were also determined. Dissolved organic carbon content, phenolic compound content, and microbial activity were measured in bulk soil and rhizosphere soil. The results show that elevated $CO_2$ significantly increased the root dry weight of pine seedling. In addition, overall N content decreased, which increased the C:N ratio in pine needles. Elevated $CO_2$ decreased soil moisture, nitrate concentration, and the concentration of soil phenolic compounds. In contrast, soil enzymatic activities were increased in rhizosphere soil, including ${\beta}$-glucosidase, N-acetylglucosaminidase and phosphatase enzyme activities. In conclusion, elevated $CO_2$ concentrations caused distinct changes in soil chemistry and microbiology.

• Macromolecular Research
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• 제13권4호
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• pp.339-343
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• 2005

Microbial hydrogel was prepared by ${\gamma}-irradiation$ of poly(${\gamma}-glutamic acid$) (PGA) which was produced from Bacillus subtilis BS 62 and it's physico-chemical characteristic was examined. The hydrogel, prepared from 10% PGA with the dose of 48 kGy, was swollen up to 1,370 times of specific water content as dry weight basis. The hydrogels obtained above the dose of 48 kGy appeared to have higher compressive strength but lower specific water content. The period to reach a swelling equilibrium for the hydrogel in deionized water at the temperature range of 4 to $45^{\circ}C$ was about 10 h. The swollen hydrogel was shrunk in ionic solutions with the increase of ionic strength, and the rate of shrinkage was greater in calcium chloride solution than in sodium chloride. Specific water content of the hydrogel was quickly decreased at $80^{\circ}C$, showing a thennally hydrodegradable property.

• 한국식품저장유통학회지
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• 제11권1호
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• pp.34-37
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• 2004

유청칼슘을 0.5%, 1.0% 및 1.5%씩 첨가하여 만든 김치를 1$0^{\circ}C$에서 숙성시키면서 pH, 적정산도, 환원당 함량, 총균수 및 유산균수를 측정한 결과는 다음과 같았다. 김치의 담금 직후부터 유청칼슘을 첨가한 시험구가 대조구보다 높은 pH를 유지하였다. 숙성 5일까지는 시험구간에 적정산도의 차이가 거의 나타나지 않았으나 그 이후에는 유청칼슘을 첨가한 시험구의 적정산도가 대조구보다 모두 높았다. 특히 유청칼슘의 첨가량이 많을수록 적정산도가 높았다. 유청칼슘을 첨가한 시험구는 김치 담금시부터 총균수 및 유산균가 많았으며, 유청칼슘의 첨가량이 많을수록 총균수 및 유산균수가 더 많았다.