• Membrane and Water Treatment
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• 제6권6호
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• pp.501-512
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• 2015

A laboratory-scale submerged membrane bioreactor (MBR) was continuously operated for 100 d at an infinite sludge retention time (SRT) with the aim of identifying possible relation between the filterability of mixed liquor and sludge properties, such as extracellular polymeric substances (EPS), soluble microbial products (SMP), viscosity of mixed liquor, zeta potential of flocs and particle size distributions (PSD). Research results confirmed that MBR can operate with a complete sludge retention ensuring good treatment performances for COD and $NH_3-N$. However, the long term operation (about 40 d) of MBR with no sludge discharge had a negative influence on sludge filterability, and an increase in membrane fouling rates with the time was observed. There as a strong correlation between the sludge filterability and the fouling rate. Among the different sludge properties parameters, the concentration SMP and EPS had a more closely correlation with the sludge filterability. The concentrations of SMP, especially SMP with MW above 10 kDa, had a strong direct correlation to the filterability of mixed sludge. The protein fractions in EPS were biodegradable and available for microorganism metabolism after about 60 days, and the carbohydrates in EPS had a significantly negative effect on sludge filterability in MBR at an infinite SRT.

• Membrane and Water Treatment
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• 제8권4호
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• pp.337-353
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• 2017

Membrane fouling at different solids retention times (SRT) (7, 12 and 20 days) was studied under well-controlled conditions in a laboratory-scale aerobic submerged membrane bioreactor under constant biomass concentration using a synthetic high strength wastewater. An increase in SRT was found to improve membrane performance and this correlated to changes in the total production of bound extracellular polymeric substances (EPS), and the composition and properties of bound EPS using X-ray photoelectron spectroscopy (XPS) and Fourier transform-infrared spectroscopy (FTIR) and floc sizes. A larger amount of total bound EPS was found at the lowest SRT (7 days) tested but the ratio of proteins (PN) to carbohydrates (CH) in bound EPS increased with an increase in SRT. Similarly, the quantity of soluble microbial products (SMP) decreased with an increase in SRT and the SMP PN/CH ratio increased with an increase in SRT. SMP concentrations positively correlated to the percentage of membrane pore blocking resistance. The quantity of total bound EPS and total SMP positively corresponded to the membrane fouling rate, while the PN/CH ratio in the bound EPS and SMP negatively correlated to the membrane fouling rate. The results show that both the quantity and composition of bound EPS and SMP and floc sizes are important in controlling membrane fouling.

• 한방비만학회지
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• 제17권2호
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• pp.140-144
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• 2017

고도비만 여성환자 1명을 대상으로 감로수 절식요법과 더불어 절식기 동안 수용성 식이섬유를 함께 공급한 결과 절식 전보다 혈중 T-cholesterol -37.4%, LDL-C -39.7%, triglyceride -39.0%, HDL-C가 -27.0% 감소하였다. 향후 감로수 절식요법을 심혈관계 질환의 예방과 치료를 위한 방법으로 사용하기 위해서는 HDL-C 감소를 보완할 수 있는 추가 연구가 필요하리라 생각된다.

• 한국초지조사료학회지
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• 제42권2호
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• pp.120-126
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• 2022

The objective of this study was to determine effects of phosphorus on lignification and carbohydrate metabolism in Kentucky bluegrass under drought stress. Drought stress was induced by reducing of water to plants in pots. Two types of phosphorus were applied as potassium phosphate (PO₄^3-; P) or potassium phosphonate (PO₃^3-; PA) in drought-stressed plants. Drought had significant negative effects on plant growth, as revealed by reduced biomass of shoot. Drought-induced increase of lignin content was concomitant with the increase of phenylalanine ammonia-lyase (PAL). Soluble sugar content was highly increased but fructan content was largely decreased by drought stress. However, the application of phosphorus was efficient to ameliorate the adverse effects of drought. PA application improved reduced shoot growth and relative water content, and inhibited lignification synthesis with a reduction of PAL activity. P or PA application maintained soluble sugar and fructan content at similar levels to controls under drought stress. These results indicate that phosphorus application may mitigate the drought stress by inhibiting the lignification and promoting the fructan assimilation.

• 한국초지조사료학회지
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• 제11권4호
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• pp.203-208
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• 1991

본 연구는 하계기온 및 질소시용이 orchardgrass 그루터기의 저장탄수화물과 섬유소함양에 미치는 영향을 구명하기 위하여 냉해가 심했던 1980년과 하고현상이 심했던 1984년의 자료를 비교 검토할 목적으로 수행되었는데 orchardgrass 그루터기에 있어서 탄수화물함양과 NDF, ADF 및 hemicellulose의 함양을 대상으로 비교분석하였다. 1. Orchardgrass 그루터 기의 수용성탄수화물함량은 서늘한 계절에 축적되었고 고온기간에 감소하였다. 그리고 생육을 개시한후 신엽발생시 감소한 다음 생육이 진전됨에 따라 증가하였다. 2. 여름철 orchardgrass 그루터기의 저장탄수화물함양은 냉해가 심했던 년도가 하고가 심했던 년도의 두배정도 높았고, 저장속도가 더 빠르게 나타났다. 그리고 저장탄수화물함양은 질소시용에 의하여 낮은 경향을 나타냈으나 유의차는 없었다(p<. 05). 3, 여름철 orchardgrass 그루터기의 DNF, ADF 및 hemicellulose함양은 냉해가 심했던 년도와 하고가 심했던 년도간에 큰 차이가 없었다. 그러고 질소시비수준에 의해서도 차이가 나타나지 않았다. 4. 여름철 시비수준별 orchardgrass 그루터기의 탄수화물함양과 NDF, ADF 및 hemicellulose함양과의 상관관계는 냉해가 심했던 년도에는 모두 부의 상관관계 경향을 나타났으나 하고가 심했던 년도에는 일관성이 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권12호
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• pp.1701-1704
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• 2001

The evaluation of structural carbohydrate losses and its effect on silages digestibility in alfalfa (Medicago sativa L.) and orchardgrass (Dactylis glomerata L.) was studied during 5, 21 and 56 days ensiling. About 70 and 60 kg fresh matter of the two forages were ensiled in 9 silos of 120 L capacity. The digestion trials were conducted in two phases using the two grasses in two $4{\times}4$ Latin square design according to the four treatments being the grass and the three silages. There were no differences in the DM and CP contents resulting from 5 to 56 days ensiling in both forages. The water-soluble carbohydrates (WSC), hemicelllose, pectin, and energy were slightly reduced and appeared lower in 56 days silage. The ether extract and cellulose contents slightly increased as the ensiling process advanced in the two species. Hemicellulose losses of 29 and 41 g/kg DM were obtained in alfalfa and orchardgrass, respectively, 56 days after ensiling. While the cellulose losses in both species were very little, compared to that for hemicellulose, the pectin losses, 56 days after ensiling were 15 and 12 g/kg DM in alfalfa and orchardgras respectively. The total structural carbohydrates lost (ie., hemicellulose + cellulose + pectin) in g/kg DM of fresh material forage ensiled, is about four fifths the amount lost by WSC, in alfalfa and about two thirds, in orchardgrass, by 21 days ensiling after the activity of microorganism terminated, indicating that appreciable amount was used as substrate for silage fermentation. Ensiling alfalfa and orchardgrass for 0, 5, 21 and 56 days maintained a decreasing trend of 83.8, 82.5, 79.3 and 78.9% digestibility in alfalfa and 80.5, 77.0, 77.1 and 76.4% digestibility in orchardgrass. While the digestibility of cellulose and ether extract increased in silage in both species, the digestible energy values in silage were reduced from 2.6 to 2.3 and 2.9 to 2.7 Mcal/kg DM respectively in alfalfa and orchard during 5-56 days ensiling.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.529-533
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• 1999

In addition to catalyzing the synthesis of dextran from sucrose as a primary reaction, dextransucrase also catalyzes the transfer of glucose from sucrose to other carbohydrates that are present or are added to the reaction digest. We have synthesized new glucans having new structures and new characteristics, by transferring D-glucose of sucrose to $\alpha$-cellulose and by using the constitutive dextransucrase obtained from Leuconostoc mesenteroides B-742CBM. The final reaction products were composed of soluble- and insoluble-glucans. The yields of soluble- and insoluble-glucans were theoretically 21% $\pm$ 2.2 and 68% $\pm$ 5.1, respectively. The remainder of the reaction products was recovered as a mixture of olgiosaccharides that could not be precipitated by 67%(v/v) ethanol. Treating the modified glucans with endo-dextranase and/or cellulase, oligosaccharides were produced that were not formed from the hydrolysis of native cellulose or B-742CBM dextran. The modification of the cellulose was confirmed by methylation and acid hydrolysis of the soluble-and insoluble-glucan. Both (1->4) and(1->6) glycosidic linkages were found in both of the glucans.

• 한국유기농업학회지
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• 제5권2호
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• pp.105-115
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• 1997

This experiment was conducted to clarify the plant growth promoting effect of compost supplemented with cultured solution of photosynthetic bacteria(Rhodopseudomonas capsulatus) before sowing on the early growth of plug seedling of tomato and to evaluate the optimum concentration of bacterialization. Bacterializing concentrations(v/w) to the compost were 2%, 3.3%, 10%, 20% and 50%, respectively. Plant growth in terms of plant height, stem diameter, leaf area, total fresh and dry weight were promoted by the bacterialization of photosynthetic bacteria. Especially, in the plots supplemented with 10 to 20% the early growth was promoted markedly over 2 times. Compositions of photosynthetic bacteria consisted of crude protein 60.7%, soluble carbohydrates 20.1%, crude fat 7.6%, crude fiber 3.2% and crude ash 4.8, respectively.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2010년도 심포지엄 및 추계학술발표회
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• pp.509-510
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• 2010

• Mycobiology
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• 제30권2호
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• pp.96-101
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• 2002

Four pathogenic fungal isolates belonging to different genera including Alternaria, Fusarium and Curvularia were isolated from selected diseased weeds growing in the fields in Dakahalia district. The inoculum of these pathogenic fungi specific to weeds were cultured, standardized and formulated as alginate pellets containing mycelium plus culture filtrate. These mycoherbicides were evaluated for disease severity(DS). Maximum DS was obtained with the alginate pellets of mycelium filtrate Fusarium solani. Physiological changes of the treated weed were determined 5 aiid 10 days after treatments. As compared to the healthy weeds, all mycoherbicide formulations significantly decreased the amount of photosynthetic pigments and subsequently soluble and insoluble sugars in the infected weeds. The mycoherbicide formulation of F. solani had the greatest effect on lowering to the abovementioned amount in the leaves of Chenopodium murale. Generally, treatment of weed leaves with the specific mycoherbicide led to a highly significant increase in total phenol content when compared to the healthy control weed. C. murale infected with the mycoherbicide formulation of F. solani had higher levels of phenolic compounds than those other treated weeds particularly after 10 days of inoculation.