• 한국토양비료학회지
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• 제46권3호
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• pp.182-186
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• 2013

In this study, we examined the chemical properties and microbial community characteristics in 25 controlled horticultural soils (CHS) sampled from Gyeongnam Province by fatty acid methyl ester (FAME) method. The electrical conductivity of watermelon CHS was significantly (p < 0.05) higher than those of red pepper CHS, pumpkin CHS, and strawberry CHS. The amounts of total FAMEs, total bacteria, gram-negative bacteria, gram-positive bacteria, and fungi were significantly (p < 0.05) higher in red pepper CHS than those in strawberry CHS and pumpkin CHS. In addition, higher (p < 0.05) ratios of cy19:0 to $18:1{\omega}7c$ were detected in tomato CHS than those in watermelon CHS, pumpkin CHS, and red pepper CHS. This implied that microbial communities of tomato CHS were stressed more than other species of cultivation soils. Actinomycetes community in red pepper CHS was significantly (p < 0.05) higher than those in tomato CHS, strawberry CHS, and watermelon CHS. Differences in soil microbial community composition were highly associated with cultivated crop species which might result from the management inputs such as fertilizer, herbicide, and irrigation.

• 한국토양비료학회지
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• 제49권5호
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• pp.621-626
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• 2016

The present study evaluated the variations in soil microbial population of controlled horticultural land used for lettuce (Lactuca sativa) cultivation by their fatty acid methyl ester and chemical properties. We utilized four treatment groups, no treatment (NT), culture medium (CM), Bacillus subtilis S37-2 (KACC 91281P) ${\times}10^6CFU\;mL^{-1}$ (BS1), and Bacillus subtilis $S37-2{\times}10^7CFU\;mL^{-1}$ (BS2) and analyzed these variations throughout the before treatment and harvesting stage. The chemical properties such as pH, organic matter, available phosphate, and electrical conductivity in soils before treatment and harvesting stage showed no significant difference among the treatments. Total numbers of bacteria and microbial biomass C in soil treated with BS1 were larger than those of NT, CM, and BS2, whereas total number of fungi at the harvesting stage was significantly lower in the BS1 soil than in the NT and CM soils (P < 0.05). On basis of leaf length, leaf width, leaf number and leaf weight, the growth characteristics lettuce on the soil treated with BS1 and BS2 was faster than those of NT and CM soils. Yield of lettuce with treated BS1 and BS2 were 35% and 29% more than that of NT, respectively.

• 한국초지조사료학회지
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• 제37권3호
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• pp.201-207
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• 2017

Hay-making is one of the most common forage preservation practices in livestock operations. The objective of hay-making is to minimize nutrient loss by shortening field drying time. Measuring the impacts of cutting height of forage crop is necessary to optimize hay production balancing yield and quality, in order to obtain substantial biomass increase through harvest of regrowth. This experiment was conducted to investigate the impact of cutting height of rye (Secale cereale L.) on drying rate and hay quality. Heading stage rye was harvested at 8cm or 15cm stubble heights. Hay was daily tedded at 09:00 and sampled at 09:00, 13:00 and 17:00 to determine moisture content (MC). After two month of preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter disappearance), TDN (total digestible nutrient), RFV (relative feed value), DM (dry matter) loss, visual scores and total fungi count were determined for estimation of hay quality. Cutting height at 15cm could enhance the drying rate and CP content (p<0.05), but also increases DM loss (p<0.05) compared to cutting at 8cm. Cutting heights did not affect ADF, NDF, IVDMD, TDN and RFV value (p>0.05). Visual scores of rye hays cutting at 8cm and 15cm, ranged from 83 to 85. Cutting at 8cm tended to maintain higher core bale temperature and fungal count than cutting at 15cm during preservation, but there was no significant difference.

• 한국자원식물학회지
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• 제31권6호
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• pp.695-703
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• 2018

Previously, we have reported a plant extract isolated from Lysimachia foenum gracum Herba as a new environment friendly biopesticide that has the mycelial growth inhibition effect on Magnaporthe oryzae, the pathogenic fungus of the rice blast disease. For the finding of additional biopesticide candidate, we tested the mycelial growth inhibitory effects about 700 species of plant extracts on PDA media. Among them, the extract of Anemarrhena asphodeloides showed prominent inhibitory effect of which $IC_{50}$ was $139.7{\mu}g/ml$. Mycelial radii of M. oryzae were measured on PDA medium containing the four organic solvent fractions isolated from total extract from A. asphodeloides. Ethyl acetate fraction showed the impressive inhibitory effect of $IC_{50}$, $54.12{\mu}g/ml$. In the subsequent rice field test for the total extract of A. asphodeloides, we obtained encouraging 62.0% control rate of rice blast disease without any phytotoxicity. It is almost equivalent to that of chemical pesticides implying the applicability of the extract as a new biopesticide. In further study, the analysis of active ingredients of the extract would be necessary for the development of a new biopesticide and for the verification of cellular mechanism by which the mycelial growth of M. oryzae inhibited.

• Journal of Animal Science and Technology
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• 제63권2호
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• pp.354-366
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• 2021

Limited data about the effects of various factors on forage quality and β-carotene content of rye produced in Korea are available, so this study investigated the effects of two preservation methods. Samples were collected from rye harvested every 5 days between April 25 and May 31, and comparisons were done among rye silage wilted for different periods of time and hay of three growth stages of rye. For the silage, dry matter (DM), acid detergent fiber (ADF), and neutral detergent fiber (NDF) contents increased with advanced maturity of rye, whereas crude protein, in vitro dry matter digestibility (IVDMD), total digestible nutrients (TDN), relative feed value (RFV), and DM loss decreased (p < 0.0001). Wilting increased the DM content and pH value significantly (p < 0.0001). Silage harvested at the heading stage had the lowest pH value (4.45), propionic acid (0.83 g/kg DM), butyric acid (0 g/kg DM), and fungi and yeast populations (3.70 Log CFU/g of fresh matter [FM]); conversely, it had the highest lactic acid (9.7 g/kg DM), lactic acid bacteria (LAB) (6.87 Log CFU/g of FM), total microorganisms (TM) (7.33 Log CFU/g of FM), and Flieg's score (70) (p < 0.0001). Wilting elevated LAB and TM populations, but it had no consistent effect on other fermentation products. Both delayed harvest and prolonged wilting decreased β-carotene content. Rye silage harvested around May 9 (heading stage) with 24 h of wilting was preferred for highland, Pyeongchang. For rye hay, advanced maturity decreased DM loss, IVDMD, TDN, and RFV, but it increased DM, ADF, and NDF significantly (p < 0.05). β-carotene was decreased by delay of hay-making. Consequently, to attain lower DM loss and higher hay quality, the harvest date of May 9 (heading stage) is recommended.

• 대한안전경영과학회지
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• 제22권4호
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• pp.9-15
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• 2020

As of 2018, total yield of lettuce and strawberry amounted to 93,543 tons (representing 1.0 percent) and 183,639 tons (2.0 percent), respectively, among total yields worth 9,185,889 tons in South Korea. Lettuce is affected by a combination of numerous elements such as varieties, cultivation methods and pests during each growth phase (Lee et al., 1999). It is mainly cultivated in spring and fall. Especially due to respiration rate after harvest leading to reduced quality and poor storage, maintaining annual supply is unavailable (Jang et al., 2018). With the distribution of new varieties, forcing culture and indoor insulated facilities for plant cultivation during winter, strawberries are produced every year except for late summer and early fall. Due to active respiration, transpiration, soft flesh and high water content, the fruit is vulnerable to go bad and got rotten compared to other fruits. Furthermore, it is difficult to maintain freshness due to the possibility of softening, discoloration and fungi (Lee et al., 2012). In this regard, developing improved storage and package techniques is needed to ensure maintaining quality and safety even just two to three days after harvest. In order to ensure improved quality and safety of strawberries and lettuce after harvest, the present study applied a modified atmosphere packaging (MAP) technology (Mostofi et. al., 2008). Going forward, it compared the quality and safety of the two products while being stored in a way that put them in an MAP-applied container and a plastic container at room temperature and 4 degree Celsius.

• Journal of Microbiology and Biotechnology
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• 제29권7호
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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.

• 아시안잔디학회지
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• 제23권2호
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• pp.219-228
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• 2009

골프장은 인공적으로 건설되어 지고 관리되므로 당연히 환경의 변화가 생성된 곳이므로 건설방식이나 관리 방법에 따라 코스 내 토양 미생물 군집 구조의 특이성이 있을 것이다. 현재 제주도에서는 농약 용탈 저감방안으로 골프코스 그린지반구조에 농약 흡착층을 설치하고 그 재료로 흡착성능이 우수한 입상 활성탄 1등급을 사용할 것을 환경 영향평가서에 명시하고 있다. 본 실험은 활성탄이 처리된 제주도 A, B 골프장을 대상으로 토양에서의 화학적 특성변화와 미생물 군락변화를 분석하였다. 2007년 4월, 6월, 8월 10월에 걸쳐서 총 박테리아 수, 총 곰팡이 수, 수분함량 및 토양 이화학성(pH, EC, NO3-,NH4+ 및 P2O5)의 변화를 그린과 페어웨이에서 깊이별(표토:0-15cm, 심토: 15-30cm)로 조사되었다. 그 결과, 활성탄의 시용이 수분 보유 능력, 토양산도, 전기전도도에 긍정적인 영향을 보였으나, GAC의 물질의 수착 능력에 의하여 유효 양분들을 많이 보유하는 데 도움이 될 것이라 예상하였으나, 본 실험에서는 가용성 질산과 암모늄, 및 인산의 농도를 높이는 효과는 없었다. 토양 미생물 실험에 있어서는 총 박테리아 및 총 곰팡이의 시기적 변화가 다양성을 보였다. 이러한 현상은 농약의 시용에 따라 직접적인 관련이 있을 것으로 예상되었으나, 총 곰팡이/총 박테리아 비(F/B ration) 는 활성탄을 혼합한 토양 심토(15-30cm)에서 일정한 수치를 유지하였다. 따라서, GAC 토양층의 설치 방법이나 시비와 시약 등이 미생물군집의 변화에 영향을 주며 이는 농약의 시용이 잔디관리에 큰 변수로 작용한다는 것을 시사한다.

• 미생물학회지
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• 제49권4호
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• pp.309-312
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• 2013

진균류의 세포벽은 다양한 결합의 글루칸과 키틴질로 구성되었으며 이들의 생활사 전체에 해당하는 균사생장과 분화과정에서 키틴질 분해효소(chitinase)를 생성한다. 먹물버섯의 하나인 Coprinellus congregatus는 전 생활사 동안 최소 2종 이상의 chitinase를 생성한다. Chi1은 균사시기부터 버섯의 자가분해 시기까지 고르게 생성되며, chitinase 2는 버섯 자가분해 시기에 다량 생성된다. Chi1의 cDNA 유전자를 Pichia pastoris의 발현벡터의 하나인 pPICZB 벡터의 c-myc과 6x Histidine tag을 포함하는 Chi1 재조합 단백질 발현벡터를 구축하고 이를 발현시킨 후, Histidine tag에 의한 affinity chromatography 방법으로 Chi1 단백질을 정제하였다. 정제된 Chi1은 endochitinase의 기질인 4-nitrophenyl N,N',N"-triacetyl-${\beta}$-D-chitotrioside에 대하여 활성을 보였다. 이를 기질로 사용했을 때 최적 pH는 8.0이었고, 최적 온도는 $35^{\circ}C$로 확인되었다. $K_m$ 값과 $V_{max}$ 값은 각각 0.780 mM과 0.10 (OD $min^{-1}unit^{-1}$)로 나타났다. 이러한 생화학적 특성은 버섯 자가분해 시기에 작용할 것으로 판단되는 Chi2가 exochitinase 활성을 보이며, pH 4.0에서 최대 활성을 보이는 것을 종합하면 상호 보완작용을 할 것이라고 판단된다. 정제된 Chi1은 Alternaria alternata, Fusarium graminearum 및 Trichoderma harzianum 등과 같은 식물 병원성 균류에 처리한 결과 60 ${\mu}g/ml$ 농도에서 이들의 생장을 완전하게 억제하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권7호
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• pp.952-960
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• 2013

The objective of this study was to investigate the effect of carbohydrate source and cottonseed meal level in the concentrate on feed intake, nutrient digestibility, rumen fermentation and microbial protein synthesis in swamp buffaloes. Four, 4-yr old rumen fistulated swamp buffaloes were randomly assigned to receive four dietary treatments according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design. Factor A was carbohydrate source; cassava chip (CC) and CC+rice bran at a ratio 3:1 (CR3:1), and factor B was level of cottonseed meal (CM); 109 g CP/kg (LCM) and 328 g CP/kg (HCM) in isonitrogenous diets (490 g CP/kg). Buffaloes received urea-treated rice straw ad libitum and supplemented with 5 g concentrate/kg BW. It was found that carbohydrate source did not affect feed intake, nutrient intake, digested nutrients, nutrient digestibility, ammonia nitrogen concentration, fungi and bacterial populations, or microbial protein synthesis (p>0.05). Ruminal pH at 6 h after feeding and the population of protozoa at 4 h after feeding were higher when buffalo were fed with CC than in the CR3:1 treatment (p<0.05). Buffalo fed with HCM had a lower roughage intake, nutrient intake, population of total viable and cellulolytic bacteria and microbial nitrogen supply than the LCM fed group (p<0.05). However, nutrient digestibility, ruminal pH, ammonia concentration, population of protozoa and fungi, and efficiency of microbial protein synthesis were not affected by cottonseed meal levels (p>0.05). Based on this experiment, concentrate with a low level of cottonseed meal could be fed with cassava chips as an energy source in swamp buffalo receiving rice straw.