• Bulletin of the Korean Chemical Society
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• 제15권9호
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• pp.791-795
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• 1994

1,3-Dimethyl and dipropyl ethers of p-t-butylcalix[4]arene and calix[4]arenes have been converted to the corresponding diesters, acetate and propionate, and their conformations are inferred based on the $^1H$ and $^{13}C$ NMR spectra. The presence of t-butyl groups is effective in maintaining the cone conformation on derivatization.

• Asian-Australasian Journal of Animal Sciences
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• 제27권8호
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• pp.1088-1097
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• 2014

The study aimed to investigate the effects of gynosaponin on in vitro methanogenesis under different forage-concentrate ratios (F:C ratios). Experiment was conducted with two kinds of F:C ratios (F:C = 7:3 and F:C = 3:7) and gynosaponin addition (0 mg and 16 mg) in a $2{\times}2$ double factorial design. In the presence of gynosaponin, methane production and acetate concentration were significantly decreased, whereas concentration of propionate tended to be increased resulting in a significant reduction (p<0.05) of acetate:propionate ratio (A:P ratio), in high-forage substrate. Gynosaponin treatment increased (p<0.05) the butyrate concentration in both F:C ratios. Denaturing gradient gel electrophoresis (DGGE) analysis showed there was no apparent shift in the composition of total bacteria, protozoa and methanogens after treated by gynosaponin under both F:C ratios. The real-time polymerase chain reaction (PCR) analysis indicated that variable F:C ratios significantly affected the abundances of Fibrobacter succinogenes, Rumninococcus flavefaciens, total fungi and counts of protozoa (p<0.05), but did not affect the mcrA gene copies of methanogens and abundance of total bacteria. Counts of protozoa and abundance of F.succinogenes were decreased significantly (p<0.05), whereas mcrA gene copies of methanogens were decreased slightly (p<0.10) in high-forage substrate after treated by gynosaponin. However, gynosaponin treatment under high-concentrate level did not affect the methanogenesis, fermentation characteristics and tested microbes. Accordingly, overall results suggested that gynosaponin supplementation reduced the in vitro methanogenesis and improved rumen fermentation under highforage condition by changing the abundances of related rumen microbes.

• Asian-Australasian Journal of Animal Sciences
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• 제3권4호
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• pp.323-330
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• 1990

Two experiments were conducted to evaluate the effect of processing and method of ensiling on the digestion and utilization of high moisture barley (HMB) in cattle. In experiment 1, four Holstein heifers were assigned in a Latin square design to diets containing 70% barley, 25% alfalfa hay and 5% supplement on a dry matter (DM) basis. Diets differed only in the type of barley fed: rolled dry barley (R-DB), rolled HBM (R-HMB), ground HMB (G-HMB) or unprocessed HMB (U-HMB). In experiment 2, three Holstein steers were fed 85.2% barley, 10.2% whole plant barley silage and 4.6% supplement on a DM basis. Again, diets differed only in the type of barley fed: R-DB, rolled HMB from a pit silo (Pit-HMB) or rolled HMB from a Harvestore silo (HAV-HMB). In experiment 1, digestibility coefficients for animals fed R-HMB were significantly higher than observed for U-HMB. While not significant, a similar trend for decreased digestibility was observed for R-DB and G-HMB. Animals fed HMB had significantly lower ruminal propionate concentrations. In addition, the rate of degradation of the degradable DM and crude protein (CP) fractions was slower for HMB than for dry barley. In experiment 2, a trend to lower digestibility coefficients was observed for animal fed R-DB compared to those fed Pit-HMB or HAV-HMB. Ruminal propionate concentrations for animals fed R-DB also tended to be higher than for those fed the HMB diets. Dry matter and CP disappearances from nylon bags was substantially lower for Pit-HMB than for R-DB or HAV-HMB. The results suggest that replacement of dry barley by rolled or unprocessed HMB in the diet of animals fed high grain diets may contribute to a more stable rumen environment.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.75-81
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• 2007

The object of this study was to determine the influence of supplementation of concentrate containing high levels of cassava chip on rumen ecology, microbial protein and digestibility of nutrients. Four, rumen fistulated crossbred beef steers with initial body weight of 400${\pm}$10 kg were randomly assigned according to a 4${\times}$4 Latin square design. The dietary treatments were concentrate cassava chip based offering at 0, 1, 2 and 3% BW with urea-treated rice straw fed ad libitum. It was found that ruminal pH was significantly decreased with increase of concentrate. Volatile fatty acids (VFA) concentration in the rumen was significantly different among treatments. In addition, a molar proportion of propionate was higher in supplemented groups at 2 and 3% BW (p<0.05), leading to significantly decreased acetate:propionate ratio. Furthermore, microbial N supply was significantly improved and was highest at 2% BW supplementation. The efficiency of rumen microbial-N synthesis based on organic matter (OM) truly digested in the rumen was highest in level of concentrate supplementation at 2% BW (80% of cassava chip in diets). Moreover, bacterial populations such as amylolytic bacteria was linearly increased, while cellulolytic bacteria was linearly decreased (p<0.01) when cattle received concentrate supplementation in all levels. The total protozoal counts were significantly increased, while fungal zoospores were dramatically decreased in cattle receiving increased levels of concentrate. In conclusion, cassava chip can be use as energy source at 80% in concentrate and supplementation of concentrate at 2% BW with urea-treated rice straw as roughage could improve rumen fermentation efficiency in beef cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제22권1호
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• pp.42-48
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• 2009

An in vitro incubation study was conducted to investigate effects of 2-bromoethanesulfonic acid (BES) on ruminal fermentation characteristics and methanogen population. BES at the final concentration of 0, 1 and 5 mM with two different substrates having a different ratio of timothy and concentrate (100% timothy vs. 40% timothy-60% concentrate) was incubated for 0, 24, 48 and 72 h in a $39^{\circ}C$ incubator. Total DNA extracted from culture fluid was used as a template for real-time PCR to measure the population of methanogens. Four different primer sets were used for amplification of total bacteria, total methanogens, the order Methanobacteriales and the order Methanomicrobiales. BES reduced (p<0.01) total gas and methane production in a dose-dependent manner. BES at 5 mM inhibited methane production by more than 95% compared to the control. An interaction between substrate and level of BES in total gas and methane was detected (p<0.01). The decrease of methane production with increasing BES level was more pronounced on mixed substrate than on timothy alone. However, hydrogen production was increased by BES treatment (p<0.01). Total VFA concentration was not affected, but molar percentage of propionate and butyrate was increased and acetate to propionate ratio was reduced by BES treatment (p<0.01). BES did not affect the population density of total bacteria but reduced (p<0.01) the population of total methanogens, the order Methanobacteriales and the order Methanomicrobiales in a dose-dependent manner. The type of substrate did not influence the trend, although the magnitude of response was different between all-roughage and 40% roughage substrate.

• Asian-Australasian Journal of Animal Sciences
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• 제33권6호
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• pp.941-948
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• 2020

Objective: This study was carried out to determine the effects of elevated dietary cation and anion difference (DCAD) on dry matter intake (DMI) and ruminal fermentation pattern in lactating dairy goats under tropical conditions. Methods: Ten dairy goats were divided into two groups of five animals each. The groups received diets at different DCAD levels, either a control diet (22.81 mEq/100 g dry matter [DM], DCAD-23) or a DCAD-39 diet (39.08 mEq/100 g DM, DCAD-39). After parturition, DMI and water intake were recorded daily. Ruminal fluid and urine were collected, and nutrient digestibility measurements were carried out at 8th weeks postpartum (PP-8). Blood samples were collected at PP-4 and PP-8 to measure plasma leptin. Results: Dry matter intake/body weight (DMI/BW) at PP-8 of the animals fed the DCAD-39 diet was significantly higher than those fed with DCAD-23 diet (p<0.05). Animals fed with DCAD-39 consumed more water than those fed DCAD-23 over 24 h, particularly at night (p<0.05). Ruminal pH, acetate concentration, and urinary allantoin excretion increased with the DCAD-39 diet, whereas ruminal butyrate concentration was lower with the DCAD-39 diet. On the other hand, other ruminal parameters, such as total volatile fatty acid concentration, propionate molar proportion and acetate/propionate average ratio, were not affected by increased DCAD supplementation. Apparent digestibility was improved by increased DCAD supplementation. Plasma leptin concentration was higher with DCAD supplementation. Conclusion: When feeding goats with DCAD-39 under tropical conditions, an increase in DMI was associated with improved apparent digestibility of nutrients, ruminal fermentation and microbial protein synthesis. An increase in plasma leptin concentration could not explain the effect of high DCAD on DMI.

• Asian-Australasian Journal of Animal Sciences
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• 제26권7호
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• pp.935-944
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• 2013

Essential oils have been shown to favorably effect in vitro ruminal fermentation, but there are few in vivo studies that have examined animal responses. The objective of this study was to evaluate the effects of thyme (THY) and cinnamon (CIN) essential oils on feed intake, growth performance, ruminal fermentation and blood metabolites in feedlot calves fed high-concentrate diets. Twelve growing Holstein calves ($213{\pm}17kg$ initial BW) were used in a completely randomized design and received their respective dietary treatments for 45 d. Treatments were: 1-control (no additive), 2-THY (5 g/d/calf) and 3-CIN (5 g/d/calf). Calves were fed ad libitum diets consisting of 15% forage and 85% concentrate, and adapted to the finishing diet by gradually increasing the concentrate ratio with feeding a series of transition diets 5 wk before the experiment started. Supplementation of THY or CIN did not affect DMI and ADG, and feed efficiency was similar between treatment groups. There were no effects of additives on ruminal pH and rumen concentrations of ammonia nitrogen and total VFA; whereas molar proportion of acetate and ratio of acetate to propionate decreased, and the molar proportion of propionate increased with THY and CIN supplementation. Rumen molar concentration of butyrate was significantly increased by adding CIN compared to control; but no change was observed with THY compared with control group. No effects of THY, or CIN were observed on valerate, isobutyrate or isovalerate proportions. Plasma concentrations of glucose, cholesterol, triglyceride, urea-N, ${\beta}$-hydroxybutyrate, alanine aminotransferase and aspartate aminotransferase were not changed by feeding THY or CIN. Results from this study suggest that supplementing a feedlot finishing diet with THY or CIN essential oil might be useful as ruminal fermentation modifiers in beef production systems, but has minor impacts on blood metabolites.

• 한국물환경학회지
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• 제26권4호
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• pp.608-613
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• 2010

Electricity generation of microbial fuel cells (MFC) is greatly affected by the kind of feed substrates because substrates would change microbial community of electrochemically active bacteria (EAB) able to transfer electrons to electrode. The effect of different substrates on electricity generation and microbial community of MFC was investigated. Two-chamber MFCs fed with acetate (A-MFC), butyrate (B-MFC), propionate (P-MFC), glucose (G-MFC) and a mixture (M-MFC) of the 4 substrates (acetate : butyrate : propionate : glucose = 1 : 1 : 1 : 1 as $COD_{Cr}$ base) were operated under continuous mode. The maximum power density was found from the M-MFC ($190W/m^3$) which showed the lowest internal resistance ($89{\Omega}$). The maximum power densities of the pure substrates feed MFCs were in order of A-MFC ($25W/m^3$), P-MFC ($21W/m^3$), B-MFC ($20W/m^3$) and G-MFC ($9W/m^3$). In DGGE analysis, the microbial community structure in suspension was quite different from each others depending on feed substrates, while the community structure in the biofilm was relatively similar regardless of the substrates. This result suggests that the feed substrates would affect the microbial community of suspended growth bacteria than attached growth bacteria resulting in difference of electricity generation in MFCs.

• 한국식품위생안전성학회지
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• 제15권3호
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• pp.179-185
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• 2000

소르빈산등 14종류의 보존료가 사용된 식품소비량과 식품첨가물의 최대허용량을 이용하여 보존료 섭취에 대한 안전성을 평가하고, 보존료 중 더욱 정밀한 섭취량 조사가 필요한 품목을 선별하였다. 가장 섭취량이 많은 보존료는 안식향산 및 안식향산나트륨으로 총 섭취량은 안식향산으로서 85.65mg이며 1일 섭취허용량에 대한 1일 추정섭취량의 비율은 31%이며 특히 청량음료로부터 안식향산의 섭취량이 가장 많은 것으로 추정되었다. 소르빈산 및 소르빈산칼륨으로 총 추정 섭취량은 76.61mg이며 1일 추정섭취량은 1일 섭취허용량의 5%이다. 나머지 보존료의 1일 추정섭취량은 1일 섭취허용량에 대한 비율이 2%이하로 현재 사용되고있는 보존료의 섭취수준은 안전한 것으로 평가할 수 있었다.

• 한국식품영양과학회지
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• 제26권2호
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• pp.209-213
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• 1997

민간요법에서 각종 질병치료에 사용되고 있는 어성초의 항균활성 물질을 규명하기 위한 목적으로 연속증류추출장치를 이용하여 포집한 휘발성 정유를 GC-MS로 각 성분을 분리 동정했다. 그 결과 어성초의 휘발성 정유는 GC column에서 52종의 화합물로 분리되었으며, 이중 44종의 화합물이 GC-MS에서 동정되었다. 밝혀진 화합물들은 terpene류 25종, aldehyde류 7종, alcohol류 4종, ketone류 3종 및 기타 5종이며, 이들 중 주요 화합물은 ${\beta}-myrcene$, ${\beta}-ocimene$, decanal, 2-undecanone 및 geranyl propionate이었다.