• 한국수산과학회지
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• 제31권6호
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• pp.875-881
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• 1998

젓갈 및 자건품으로 소비량이 많은 멸치의 기능특성해석 및 기능성 조미 소재 제조의 일환으로 단백질 분해효소에 의한 멸치 육단백질 가수분해물의 peptide-nitrogen 생성량과 ACE 저해작용을 검토하였다. 소화효소와 식품공업용 단백질분해효소를 이용한 탈지 멸치육 가수분해물의 $50\%$ ethanol 가용성 peptide-nitrogen 생성량은 반응 8시간을 전후로 하여 거의 일정수준에 도달하였고, ACE 저해효과 역시 높게 나타났다. 따라서, 가수분해 8시간째의 각 효소 가수분해물의 peptide-nitrogen의 함량과 ACE 저해효과를 검토한 결과, 소화효소의 경우, $\alpha$-chymotrypsin으로 가수분해시켰을 때, $50\%$ ethanol 가용성 peptide-nitrogen의 생성량과 ACE 저해효과가 높은 것으로 나타났다 또한, 식품공업용 단백질분해 효소를 사용한 경우는 Alcalase 0.6L를 사용하였을 때가 $50\%$ ethanol 가용성 peptide-nitrogen의 생성량 및 ACE 저해효과가 가장 우수하였고, Protamex에 의해서는 $50\%$ ethanol 가용성 peptide-nitrogen의 생성량은 적었지만, ACE 저해효과는 높게 나타났다. ACE 저해효과가 우수한 멸치육 효소 가수분해물의 $50\%$ ethanol 가용성 획분의 아미노산 조성은 대부분의 가수분해물에서 glutamic acid의 함량이 가장 많았고, 그 다음으로 aspartic acid. cysteine 및 leucine의 순이었다.

• 한국가금학회지
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• 제36권4호
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• pp.351-356
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• 2009

본 연구는 옥수수 DDGS의 색상과 phytase 첨가가 회장 아미노산 소화율에 미치는 영향을 조사하기 위하여 실시하였다. 공시 재료는 세가지 색상의 DDGS(DDGS1, DDGS2, DDGS3)를 이용하였으며, 시험계는 유사한 체중의 5주령 Ross종(Ross 308) 육계 수컷 108수(평균 체중 $1.8{\pm}0.2\;kg$)를 공시하였다. 시험 설계는 세 가지 색상의 DDGS와 phytase 첨가 3처리구(0, 500, 1,000 FTU/kg)의 $3{\times}3$ 복합 요인으로 총 9처리구, 처리당 12수씩 완전 임의 배치 하여 7일 동안 소화 시험을 실시하였다. DDGS의 색상은 각각 DDGS1이 $L^*=55.2$, $a^*=8.8$, $b^*=41.3$, DDGS2가 $L^*=39.8$, $a^*=7.5$, $b^*=27.1$, DDGS3이 $L^*=28.3$, $a^*=6.1$, $b^*=15.4$로 나타났다. DDGS의 색상에 따른 아미노산 소화율은 어두운 색이 밝은 색보다 모든 아미노산의 소화율이 낮게 나타났다. DDGS의 처리구에 phytase를 첨가하여 급여시에 소화율이 증가하는 경향이었다. 필수아미노산의 평균 소화율은 모든 처리구에서 각각 77.7, 80.0, 81.5, 76.0, 78.4, 80.1, 67.6, 69.6 및 71.0% 이었으며, 비필수 아미노산의 평균 소화율은 각각 73.6, 75.8, 77.3, 73.1, 75.3, 76.8, 67.4, 69.4 및70.7% 이었다. 이번 실험의 결과에서, DDGS 색상이 어두울수록 그리고 phytase 수준이 낮을수록 아미노산 이용률이 낮게 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권12호
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• pp.1725-1733
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• 2016

Recent findings have shown that microbial nitrogen flow and digestible energy of diets are increased when urea is combined with a slow-release urea (SRU) in diets with a starch to acid detergent fibre ratio (S:F) 4:1. This affect is attributable to enhanced synchrony between ruminal N availability for microbial growth and carbohydrate degradation. To verify the magnitude of this effects on lamb performance, an experiment was conducted to evaluate the effects of combining urea and a SRU in diets containing S:F ratios of 3:1, 4:1, or 5:1 on performance, dietary energetics and carcass characteristics of finishing lambs. For that, 40 Pelibuey${\times}$Katahdin lambs ($36.65{\pm}3kg$) were assigned to one of five weight groupings in 20 pens (5 repetition/treatments). The S:F ratio in the diet was manipulated by partially replacing the corn grain and dried distiller's grain with solubles by forage (wheat straw) and soybean meal to reach S:F ratios of 3:1, 4:1 or 5:1. An additional treatment of 4:1 S:F ratio with 0.8% urea as the sole source of non-protein nitrogen was used as a reference for comparing the effect of urea combination vs. conventional urea at the same S:F ratio. There were no treatment effects on dry matter intake (DMI). Compared the urea combination vs urea at the same S:F ratio, urea combination increased (p<0.01) average daily gain (ADG, 18.3%), gain for feed (G:F, 9.5%), and apparent energy retention per unit DMI (8.2%). Irrespective of the S:F ratio, the urea combination improved the observed-to-expected dietary ratio and apparent retention per unit DMI was maximal (quadratic effect, $p{\leq}0.03$) at an S:F ratio of 4:1, while the conventional urea treatment did not modify the observed-to-expected net energy ratio nor the apparent retention per unit DMI at 4:1 S:F ratio. Urea combination group tended (3.8%, p = 0.08) to have heavier carcasses with no effects on the rest of carcass characteristics. As S:F ratio increased, ADG, G:F, dietary net energy, carcass weight, dressing percentage and longissimus thoracis (LM) area increased linearly ($p{\leq}0.02$). Combining urea and a slow-release urea product results in positive effects on growth performance and dietary energetics, but the best responses are apparently observed when there is a certain proportion (S:F ratio = 4:1) of starch to acid detergent fibre in the diet.

• Asian-Australasian Journal of Animal Sciences
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• 제28권4호
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• pp.485-493
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• 2015

This study evaluated the in situ ruminal degradability, and subsequent small intestinal digestibility (SID) of dry matter, crude protein (CP), and amino acids (AA) of cottonseed meal (CSM), sunflower seed meal (SFSM) and distillers dried grains with solubles (DDGS) by using the modified three-step in vitro procedure. The ruminal degradability and subsequent SID of AA in rumen-undegradable protein (RUP-AA) varied among three protein supplements. The result show that the effective degradability of DM for SFSM, CSM, and DDGS was 60.8%, 56.4%, and 41.0% and their ruminal fermentable organic matter was 60.0%, 55.9%, and 39.9%, respectively. The ruminal degradable protein (RDP) content in CP for SFSM, CSM, and DDGS was 68.3%, 39.0%, and 32.9%, respectively, at the ruminal solid passage rate of 1.84%/h. The SFSM is a good source of RDP for rumen micro-organisms; however, the SID of RUP of SFSM was lower. The DDGS and CSM are good sources of RUP for lambs to digest in the small intestine to complement ruminal microbial AA of growing lambs. Individual RUP-AA from each protein source was selectively removed by the rumen microorganisms, especially for Trp, Arg, His, and Lys (p<0.01). The SID of individual RUP-AA was different within specific RUP origin (p<0.01). Limiting amino acid was Leu for RUP of CSM and Lys for both RUP of SFSM and DDGS, respectively. Therefore, different protein supplements with specific limitations should be selected and combined carefully in growing lambs ration to optimize AA balance.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1946-1955
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• 2018

Objective: This study was conducted to evaluate the effect of keratinase (KE) on the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) in rice bran, cottonseed meal (CSM), rapeseed meal (RSM), corn distillers dried grains with solubles (DDGS), and peanut meal (PNM). Methods: Twelve crossbred barrows (Duroc${\times}$Landrace${\times}$Yorkshire, $50.5{\pm}1.4kg$ body weight [BW]) fitted with T-cannulas at the terminal ileum were allotted to a $12{\times}6$ Youden Square design with 12 diets and 6 periods. The treatment diets included rice bran, CSM, RSM, corn DDGS, PNM, or corn-soybean meal (cSBM) supplemented with 0.05% KE or not. Diets were given to pigs at a level of 3% BW in two equal meals. The endogenous AA losses were the mean results of three previously experiments determined by a same nitrogen-free diet fed to pigs. Pigs had free access to water during the experiment. Results: The KE supplementation improved (p<0.05) the AID and SID of Met, Thr, Val, Asp, Cys, and Tyr in rice bran. Inclusion of KE increased (p<0.05) the AID and SID of Met and Val in CSM. The KE supplementation decreased (p<0.05) the AID and SID of His in RSM and all measured AA except for Arg, Met, Trp, Val, Gly, and Pro in corn DDGS. There was an increase (p<0.05) in AID and SID of Leu, Ile, Met, Ala, Cys, Ser, and Tyr in PNM supplemented with KE compared with that without KE. Inclusion of KE increased (p<0.05) the AID and SID of crude protein, Leu, Ile, Phe, Thr, Asp, and Ser in cSBM. Conclusion: This study indicated that KE had different effects on ileal AA digestibility of feedstuffs for growing pigs, which can give some usage directions of KE in swine feed containing those detected feedstuffs.

• 한국수산과학회지
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• 제31권3호
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• pp.423-428
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• 1998

우렁쉥이 (Halocynthia roretzi)의 껍질부분은 거의 전량 폐기되고 있는 실정이며, 이로 인한 연안오염 문제까지 대두되고 있다. 본 연구에서는 미이용자원의 효율적인 이용을 위하여. 우렁쉥이 껍질에서 카로테노이드계 색소를 추출하고 남은 잔사로부터 조다당류를 효과적으로 분리하기 위한 조건을 조사하였다. 우렁쉥이 껍질의 일반성분 조성은 색소를 함유한 것과 탈색시킨 분말 모두 거의 유사한 경향을 보였으며, 조단백질은 약 $40\%$였고, 총탄수화물은 약 $46\%$였다. 우렁쉥이 분말과 효소처리 및 autoclave처리한 조다당류의 아미노산조성은 세 시료 모두 유사한 결과였다. Histidine의 함량이 가장 많았으며, 특히 neutrase 처리구는 $29.2\%$였으며, autoclave 처리구는 $20.4\%$였다. Aspartic acid와 glutamic acid가 $9.1\~12.2\%$로 상당량 존재하였다. 필수아미노산 함량은 탈색한 분말, neutrase 처리구, autoclave 처리구 각각 $31.7\%,\;26.3\%,\;29.5\%$였다. 또한, 이들 세 시료의 무기질 함량은 조 추출물의 경우 Ca의 함량이 월등히 많았으며, 다음이 Mg과 Na 순이었다. 탈색한 시료는 Na의 함량이 가장 많았고, Ca>Mg>Fe의 순이었다. 색소 함유한 시료의 경우 Ca>Mg>Na>Fe의 순이었다. 추출방법에 따른 수율은 효소처리의 경우 neutrase $3\%$처리가 바람직하였고, 가수분해 처리시간은 24시간정도가 좋았으며, 이때 수율은 약 $10\%$였다. 한편 조다당류를 침전시킬 때 처리하는 에탄올의 농도는 $70\%$가 바람직하였길, $70\%$ 에탄올로 처리시 상온에서 방치할 때 최적 방치 시간은 15시간이었다. 한편, Autoclave를 이용하여 $125^{\circ}C$에서 처리했을 때의 조다당류의 수율은 처리시간에 따라 증가하는 경향이었고, 약 6시간 처리하였을 때 $9\%$ 이상을 나타내었다. 또한, autoclave 처리횟수에 따른 시료의 수율은 1차 처리시 조다당류가 가장 많이 추출되었으며, 처리횟수를 반복함에 따라 수율이 감소되는 경향이었다. 조다당류의 일반성분은 단백질함량이 $20\%$이내인 반면, 총탄수화물의 함량이 $60\%$이상으로 대부분을 차지하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권2호
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• pp.187-193
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• 2014

As a result of the cost of grains, the replacement of grains by co-products (i.e. DDGS) in feedlot diets is a common practice. This change produces diets that contain a lower amount of starch and greater amount of fibre. Hypothetically, combining feed grade urea (U) with slow release urea (Optigen) in this type of diet should elicit a better synchrony between starch (high-rate of digestion) and fibre (low-rate of digestion) promoting a better microbial protein synthesis and ruminal digestion with increasing the digestible energy of the diet. Four cannulated Holstein steers ($213{\pm}4$ kg) were used in a $4{\times}4$ Latin square design to examine the combination of Optigen and U in a finishing diet containing different starch:acid detergent fibre ratios (S:F) on the characteristics of digestive function. Three S:F ratios (3.0, 4.5, and 6.0) were tested using a combination of U (0.80%) and Optigen (1.0%). Additionally, a treatment of 4.5 S:F ratio with urea (0.80% in ration) as the sole source of non-protein nitrogen was used to compare the effect of urea combination at same S:F ratio. The S:F ratio of the diet was manipulated by replacing the corn grain by dried distillers grain with solubles and roughage. Urea combination did not affect ruminal pH. The S:F ratio did not affect ruminal pH at 0 and 2 h post-feeding but, at 4 and 6 h, the ruminal pH decreased as the S:F ratio increased (linear, p<0.05). Ruminal digestion of OM, starch and feed N were not affected by urea combination or S:F ratio. The urea combination did not affect ADF ruminal digestion. ADF ruminal digestion decreased linearly (p = 0.02) as the S:F ratio increased. Compared to the urea treatment (p<0.05) and within the urea combination treatment (quadratic, p<0.01), the flow of microbial nitrogen (MN) to the small intestine and ruminal microbial efficiency were greater for the urea combination at a S:F ratio of 4.5. Irrespective of the S:F ratio, the urea combination improved (2.8%, p = 0.02) postruminal N digestion. As S:F ratio increased, OM digestion increased, but ADF total tract digestion decreased. The combination of urea at 4.5 S:F improved (2%, p = 0.04) the digestible energy (DE) more than expected. Combining urea and Optigen resulted in positive effects on the MN flow and DE of the diet, but apparently these advantages are observed only when there is a certain proportion of starch:ADF in the diet.

• 임산에너지
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• 제17권1호
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• pp.56-70
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• 1998

This study was carried out to investigate the structural characteristics of kraft lignin and the wood degrading characteristics, the productivity of ligninolytic enzymes and the enzymatic degradation of kraft lignin by white-rot fungi. To purify kraft lignin, precipitation of kraft pulping black liquors of pitch pine meal was done by titration with lN $H_{2}SO_{4}$ reaching to pH 2, and isolation of the precipitates done by centrifugation. The isolated precipitates from pitch pine were redissloved in lN NaOH, reprecipitated by titration with lN $H_{2}SO_{4}$, washed with deionized water, and kept ofr analysis after freeze drying. Fractionation of the precipitates in solution by successive extraction with $CH_{2}Cl_{2}$ and MeOH, and the fractionates were named SwKL, SwKL I, SwKL II, and SwKL III for pitch pine kraft lignin. The more molecular weights of kraft lignin increased, the less phenolic hydroxyl groups and the more aliphatic hydroxyl groups. Because as the molecular weights increased, the ratio of etherified guaiayl/syringyl(G/S ratio) and the percentage were increased. The spectra obtained by 13C NMR and FTIR assigned by comparing the chemical shifts of various signals with shifts of signals from autherized ones reported. The optimal growth temperature and pH of white-rot fungi in medium were $28^{\circ}C$ and 4.5-5.0, respectively. Especially, in temperature and pH range, and mycelial growth, the best white-rot fungus selected was Phanerochaete chrysosporium for biodegradation. For the degradation pathways, the ligninolytic fungus jcultivated with stationary culture using medium of 1% kraft lignin as a substrate for 3 weeks at $28^{\circ}C$. The weight loss of pitch pine kraft lignin was 15.8%. The degraded products extracted successively methoanol, 90% dioxane and diethyl ether. The ether solubles were analyzed by HPLC. Kraft lignin degradation was initiated in $\beta$-O-4 bonds of lignin by the laccase from Phanerochaete chrysosporium and the degraded compounds were produced from the cleavage of $C\alpha$-$C\beta$ linkages at the side chains by oxidation process. After $C\alpha$-$C\beta$ cleavage, $C\alpha$-Carbon was oxidized and changed into aldehyde and acidic compounds such as syringic acid, syringic aldehyde and vanilline. And the other compound as quinonemethide, coumarin, was analyzed. The structural characteristics of kraft lignin were composed of guaiacyl group substituted functional OHs, methoxyl, and carbonyl at C-3, -4, and -5 and these groups were combinated with $\alpha$ aryl ether, $\beta$ aryl ether and biphenyl. Kraft lignin degradation pathways by Phanerochaete chrysosporium were initially accomplished cleavage of $C\alpha$-$C\beta$ linkages and $C\alpha$ oxidation at the propyl side chains and finally cleavage of aromatic ring and oxidation of OHs.

• 한국식품과학회지
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• 제30권2호
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• pp.245-252
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• 1998

키토산 올리고당 생산에 이용 가능한 경제성 있는 키토산 분해 효소를 탐색하였다. Cellulase, ${\beta}-1,4-glucosidase,\;protease$ 및 상업용 효소류를 대상으로 조제 키토산에 대한 분해력을 시험한 결과 Trichoderma viride, T. reesei 유래의 cellulase 및 상업용 효소인 Celluclast (T. reesei 유래 cellulase)가 우수한 키토산 분해능력을 나타내었다. 키토산에 대한 반응성은 T, reesei 유래 cellulase가 T. viride 유래 cellulase 보다 강하였으며 이들의 적정 키토산 분해조건은 pH 5.0이었고 적정 온도는 T. viride 유래 celluclast는 $45^{\circ}C$, T. reesei 유래 cellulase 및 Celluclast는 $55^{\circ}C$로 나타났다. 또한 dose reponse시험에서 이들 효소 모두 enz./chitosan비=0.1이 적절하였으며 T. reesei 유래 효소 및 Celluclast는 키토산 농도가 3%일 때 최대의 활성을 나타내었다. 한편, 상업용 효소인 Celluclast를 이용한 키토산 올리고당의 생산 가능성을 시험하기 위하여 3% 키토산 용액(310cp)에 Celluclast를 1% 첨가하고 $pH\;5.0,\;55^{\circ}C$에서 시간별로 반응시켰을 때, 점도는 초기30분경에 5.51cp로 98% 이상 감소하였으며 50% ethanol 가용물의 수율은 분해 15시간에 70%로 최대를 보였다. 총환원당의 함량은 분해시간이 경과함에 따라 증가하였고 반응 2시간부터 13.5% 내외의 수준을 유지하였다. 올리고당의 조성은 15시간 분해물에서 균일한 분포와 높은 함량을 보였으며 항종 양활성을 나타내는 것으로 알려진 6량체 키토산 올리고당의 생성량은 기존의 산 분해방법의 약 4배에 해당되는 8.0%로 나타났다. 따라서 T. viride 및 T. ressei 유래의 cellulase는 99% 이상의 탈아세틸화도를 가지는 키토산에 대하여 분해활성을 나타내고 특히 T. reesei유래의 상업용효소는 지금까지 효소가격이 너무 높아 활용되지 못한 chitosanase를 대신하여 키토산 올리고당을 경제성 높게 생산하는 데 이용될 수 있을 것으로 기대되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.79-85
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• 1997

Cage layer waste and sudex grass were ensiled in the proportions of 0:100, 30:70, 40:60 and 50:50 wet basis, respectively. The influence of ensiling cage layer waste on Salmonellae, Shigella, Proteus, and total number of colony forming units (CFU) was investigated. The nutritive value of the silages was evaluated in a digestion trial. The experiment was conducted with 24 wethers allotted to four silages. Initial samples of cage layer waste showed $0.11{\times}10^6$ CFU and salmonellae, Shigella and Proteus were present. Ensiling was effective in complete elimination of all the pathogens. Dry matter, crude protein and ash contents were increased linearly (p < .01) with the increase of cage layer waste in the silages ($358g{\cdot}kg^{-1}$ to $484g{\cdot}kg^{-1}$; $76.3g{\cdot}kg^{-1}$ to $183.2g{\cdot}kg^{-1}$ and $38.5g{\cdot}kg^{-1}$ to $169.4g{\cdot}kg^{-1}$; DM basis, respectively). Water solubles carbohydrate values for silages were 38.3, 22.5, 20.1 and $20.0g{\cdot}kg^{-1}$ DM basis, respectively. Ensiling decreased the pH values for all the silages and the decrease was higher for sudex grass ensiled alone than grass ensiled with cage layer waste. Lactic acid concentration in silages increased linearly (p < .01) with the increase of cage layer waste. The apparent digestibilities of DM, OM and CP for the animals fed sudex grass silage alone were 496.0, 516.1, $496.7g{\cdot}kg^{-1}$ DM basis respectively. However, digestibilities of all the components were higher (p < 0.01) for the animals fed silages containing cage layer waste. Among waste containing diets, the digestibilities of all the components showed quadratic affect (p < 0.01), increased for silages containing 30 and 40% cage layer waste and decreased when the level of waste increased from 40 to 50%. The results indicated that cage layer waste can be used upto 40% in ruminant diet as a source of N without any adverse effect on the health of animals. Ensiling appeared to be feasible and effective method for eliminating the pathogen present in cage layer waste.