• Asian-Australasian Journal of Animal Sciences
• /
• 제18권9호
• /
• pp.1267-1272
• /
• 2005

The effect of various moisture contents of fresh forage on the change in nitrogen (N) fractions, in vitro ruminal N degradability, and the subsequent N utilization of silage in sheep were evaluated. Orchardgrass (Dactylis glomerata L.) with high (HM, 76%), medium (MM, 65%) and low (LM, 40%) moisture contents were ensiled into silos of 120 L capacity for 120 days. A nitrogen balance trial was conducted using a 4${\times}$4 Latin square design consisting of four dietary treatments (i.e. fresh forage, HM, MM and LM silages) and four wethers. With respect to N fractions, fraction 1 (buffer solution soluble N), fraction 2 (buffer solution insoluble N-neutral detergent insoluble N), fraction 3 (neutral detergent insoluble N-acid detergent insoluble N), and fraction 4 (acid detergent insoluble N) were determined. The proportion of fraction 1 in silages tended to decrease, while the in vitro ruminal degradability of insoluble N increased (p<0.05) with lower moisture contents at ensiling. Consequently, nitrogen utilization in sheep tended to improve as the moisture content of ensiled grass was decreased, with a negative correlation (p<0.01) between urinary N and the in vitro ruminal degradability of insoluble N. The averaged N retentions for HM, MM, and LM silage treatments were 59, 73 and 79% of that for fresh forage, respectively.

• 한국식품영양학회지
• /
• 제23권4호
• /
• pp.562-569
• /
• 2010

This study was conducted to investigate the hypocholesterolemic effects of porphyran and insoluble dietary fiber isolated from laver in rats fed high fat diet containing 1% cholesterol, 0.25% sodium cholate and 12% lard. Rats were fed, ad libitum, diets containing 5% diet fiber as cellulose(normal control or high fat control), porphyran or insoluble dietary fiber for 4 weeks. Among the groups fed high fat diet, liver weight was significantly lower in high fat porphyran group than high fat control. Plasma GOT, GPT, total cholesterol, cholesteryl ester, LDL-cholesterol and liver total cholesterol concentration were significantly lower in high fat porphyran group than high fat control. The feeding of porphyran significantly increased fecal cholesterol and bile acid excretion. The feeding of insoluble dietary fiber had no significant effect on either plasma or liver cholesterol levels, although fecal cholesterol level in the insoluble dietary fiber group was significantly higher than that in the high fat control. The results indicate that porphyran isolated from the laver may exert their hypocholesterolemic effect by increasing excretion of fecal bile acid and cholesterol.

• BMB Reports
• /
• 제36권2호
• /
• pp.154-158
• /
• 2003

Collagen is a family of proteins which consists of several genetically distinct molecular species and is intimately involved in tissue organization, function, differentiation and development. The purpose of this study was to investigate the concentration of different hydroxyproline (Hyp) fractions viz., total, free, peptide-bound, protein-bound, soluble- and insoluble-collagen hydroxyproline (Hyp) in various bovine tissues. Results showed that liver had the highest concentration of free Hyp followed by kidney, brain, spleen, lungs, muscle and heart. Liver also had the highest concentration of peptide-bound collagen Hyp followed by kidney, heart, spleen, lungs, brain and muscle. The concentration of protein-bound collagen Hyp was highest in the liver, followed by kidney, spleen, lungs, muscle, brain and heart. Total Hyp was highest in the liver, followed by kidney, spleen, brain, heart, muscle and lungs. Liver also had significantly high concentration of collagen as compared to other tissues examined (P<0.001). Spleen had the significantly higher concentration of soluble-collagen Hyp when compared to other tissues (P<0.001). This was followed by heart, muscle, lungs, brain, kidney and liver. Heart had the highest concentration of insoluble-collagen Hyp followed by lungs, kidney, liver, muscle, spleen and brain. The variation among the insoluble-collagen Hyp concentration of heart and muscle, spleen and brain was significant (P<0.001). We speculate that these differences could be due to the variation in turn over of rate of collagen metabolism in this species.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권6호
• /
• pp.719-723
• /
• 2010

Ingestion of forage containing a large quantity of soluble oxalate can result in calcium deficiency and even death of livestock. Fertilization is one of the most practical and effective ways to improve yield and nutritional quality of forage. An experiment was conducted to determine the effects of nitrogen (N) fertilization (150, 300 and 600 kg/ha) across varying levels (150, 300 and 600 kg/ha) of potassium (K) on oxalate accumulation in napiergrass (Pennisetum purpureum). Application of N at 300 kg/ha produced higher dry matter yield than at 150 or 600 kg/ha, while K fertilization had no effect on yield. In general, N fertilization did not affect the soluble and total oxalate contents, but slightly affected the insoluble oxalate content. Soluble oxalate content showed an increasing trend and insoluble oxalate content showed a decreasing trend with increasing K level, but total oxalate content remained relatively constant. There were significant interactions between N and K fertilization for the content of soluble and insoluble oxalate fractions. The greatest increase in soluble oxalate content with N level at 300 kg/ha was found at the high level (600 kg/ha) of K application. The greatest increase in insoluble oxalate content with N level at 600 kg/ha was found at the low level (150 kg/ha) of K application. These results indicated the possibility of controlling the content of soluble and insoluble oxalate fractions in forage by fertilization.

• 한국식품영양과학회지
• /
• 제34권2호
• /
• pp.219-222
• /
• 2005

찰흑미(상해항혈나)에서 열수가용성 물질과 열수불용성 물질을 분리하여 그 전분의 겔 크로마토그래피 용출양상을 조사하였다. 열수가용성 물질은 찰흑미 전분이 16.6%,신선찰벼 전분이 13.4%였으며, 열수가용성 물질의 Sepharose CL-2B에 의한 용출양상은 두 시료 모두 void volume 부근에서 대부분 용출되었고, 열수가용성 물질에 대한 요오드복합체의 최대흡수파장은 신선찰벼 전분과 찰흑미 전분이 각각 522 nm와 520 nm로 생 전분에서의 요오드반응과 비교하여 약간의 이동이 있었다. 열수불용성 물질의 Sepharose CL-2B에 의한 용출양상은 열수가용성 물질의 용출양상과 서로 비슷하였으며 요오드복합체와의 최대흡수파장은 열수가용성 물질보다 낮았다.

• 분석과학
• /
• 제7권4호
• /
• pp.517-526
• /
• 1994

Mn의 함량을 달리하여 제조한 Al-Li-Cu-Mg-Mn-Zr 합금의 미고용상 및 분산상을 EPMA(Electron Probe Microanalyzer)와 SAEM(Scanning Auger Electron Microscope)으로 분석하였다. 또한 미고용상의 부피 분율, 분포 및 형태를 광학현미경으로 관찰하였으며, 상온과 고온에서의 인장 특성을 조사하였다. Mn의 함량이 증가함에 따라 미고용상의 부피분율을 급격히 증가하고 연신율을 감소하였다. Mn은 기지 조직의 결정립을 미세하고 균일하게 분포하도록 하였다. 인장시험 결과, 0.44 wt% Mn이 첨가된 합금이 다른 합금보다 우수한 기계적 특성을 나타내었다.

• 미생물학회지
• /
• 제30권3호
• /
• pp.213-217
• /
• 1992

Streptococcus mutans NCTC 10449 가 생산하는 Glucosyltransferase 를 순수 분리하고 그 특성을 조사하였다. 이 효소는 충치 형성 과정중 insoluble glucan 의 형성과 관련되어 있다. 이 효소의 분자량은 152,000 이며 최적 pH 와 온도는 각각 6.5 와 $35^{\circ}C$ 이며 중성이상의 pH 에서 산성에서보다 다소 안정하였다. 이 효소의 활성에 대한 Km 값은 48 mM 정도였고, 이 효소에 의해 생산된 insoluble glucan 은 타액으로 부터 분리된 균에 의해 생산된 insoluble glucan 보다 dextranase 에 의한 분해도가 높았다.

• Bulletin of the Korean Chemical Society
• /
• 제32권7호
• /
• pp.2469-2472
• /
• 2011

• Geomechanics and Engineering
• /
• 제12권5호
• /
• pp.849-862
• /
• 2017

With growing interests in using bacterial biopolymers in geotechnical practices, identifying mechanical properties of soft gel-like biopolymers is important in predicting their efficacy in soil modification and treatment. As one of the promising candidates, dextran was found to be produced by Leuconostoc mesenteroides. The model bacteria utilize sucrose as working material and synthesize both soluble and insoluble dextran which forms a complex and inhomogeneous polymer network. However, the traditional rheometer has a limitation to capture in situ properties of inherently porous and inhomogeneous biopolymers. Therefore, we used the particle tracking microrheology to characterize the material properties of the dextran polymer. TEM images revealed a range of pore size mostly less than $20{\mu}m$, showing large pores > $2{\mu}m$ and small pores within the solid matrix whose sizes are less than $1{\mu}m$. Microrheology data showed two distinct regimes in the bacterial dextran, purely viscous pore region of soluble dextran and viscoelastic region of the solid part of insoluble dextran matrix. Diffusive beads represented the soluble dextran dissolved in an aqueous phase, of which viscosity was three times higher than the growth medium viscosity. The local properties of the insoluble dextran were extracted from the results of the minimally moving beads embedded in the dextran matrix or trapped in small pores. At high frequency (${\omega}>0.2Hz$), the insoluble dextran showed the elastic behavior with the storage modulus of ~0.1 Pa. As frequency decreased, the insoluble dextran matrix exhibited the viscoelastic behavior with the decreasing storage modulus in the range of ${\sim}0.1-10^{-3}Pa$ and the increasing loss modulus in the range of ${\sim}10^{-4}-1\;Pa$. The obtained results provide a compilation of frequency-dependent rheological or viscoelastic properties of soft gel-like porous biopolymers at the particular conditions where soil bacteria produce bacterial biopolymers in subsurface.

• 한국산업보건학회지
• /
• 제30권2호
• /
• pp.87-98
• /
• 2020

Objective: The purpose of this study was to propose a sequential procedure for the simultaneous analysis of soluble and insoluble metal compounds. Methods: Methods for sampling and analyzing metal compounds such as ISO standards, NIOSH methods, HSE methods, and OSHA methods were reviewed. Results: Some metals have different OELs depending on the solubility of the compound. Therefore, we should take into account these characteristics and perform an exposure assessment. Soluble metal compounds are first extracted from the filter, and then the filter is digested by acids to analyze residual insoluble components. The extraction of soluble compounds can be completed by agitation for about 60 minutes with a leach solution (water) in a water bath at 37℃. For the analysis of insoluble compounds, the sample filter and the filtration filter remaining after the extraction of the soluble compounds are analyzed. This allows simultaneous determination of soluble and insoluble metal compounds. For hexavalent chromium compounds, soluble hexavalent chromium can first be extracted from the filter by using sulfate buffer. The insoluble hexavalent chromium remaining in the filter can then be extracted using carbonate buffer. Conclusion: Workers are often exposed to many hazardous substances with different exposure limits at industrial sites. The OELs for compounds of the same metal can be set differently depending on solubility. This study can help evaluate a worker's exposure to metal compounds by suggesting methods for the simultaneous determination of soluble and insoluble metal compounds.