• 한국식품과학회지
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• 제30권3호
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• pp.650-654
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• 1998

깍두기 숙성 중에는 초기와 후기에 산 생성이 활발하고 그 사이에 비교적 신도의 변화가 없는 시기가 관찰되었다. 세균들은 담금 직후에는 Enterobacter가 90% 이상 차지하고 있었으며 적숙기인 숙성 8일 후에는 Lactobacillus 종류가 53%, Leuconostoc 종류가 43% 그리고 과숙기인 숙성 40일 후에는 Lactobacillus 종류가 63%, Leuconostoc 종류가 37%로서 중요한 종류로 분리되었다. 젖산 구균의 대부분은 Leuconostoc mesenteroides subsp. paramesenteroides로서 적숙기에 분리된 균주들은 과숙기에 분리된 균주들에 비하여 요구하는 아미노산이 다소 증가되었으나 비타민 요구성에서는 차이가 없었다. 이들은 이와 같은 생리특성에서 시험한 9종의 Leuconostoc속 표준균주와는 다른 성질을 보이고 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1399-1406
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• 2000

A continuous culture study was conducted to determine the impact of ruminal degradable soy protein (S-RDP) level and dilution rate (D) on growth of ruminal non-structural carbohydrate-fermenting microbes. Corn starch, urea and isolated soy protein (ISP) were used to formulate three diets with S-RDP levels of 0, 35 and 70% of total dietary CP. Two Ds were 0.03 and $0.06h^{-1}$ of the fermenter volume in a single-effluent continuous culture system. As S-RDP levels increased, digestibilities of dietary dry matter (DM), organic matter (OM) and crude protein (CP) linearly (p=0.001) decreased, whereas digestion of dietary starch linearly (p=0.001) increased. Increasing D from 0.03 to $0.06h^{-1}$ resulted in decreased digestibilities of dietary DM and OM, but had no effect on digestibilities of dietary starch (p=0.77) and CP (p=0.103). Fermenter pH, the concentration of volatile fatty acids (VFA) and daily VFA production were unaffected (p=0.159-0.517) by S-RDP levels. Molar percentages of acetate, propionate and butyrate were greatly affected by S-RDP levels (p=0.016-0.091), but unaffected by D (p=0.331-0.442). With increasing S-RDP levels and D, daily bacterial counts, daily microbial N production (DMNP) and microbial efficiency (MOEFF; grams of microbial N produced per kilogram of OM truly digested) were enhanced (p=0.001). The increased microbial efficiency with increasing S-RDP levels is probably the result of peptides or amino acids that served as a stimulus for optimal protein synthesis. The quantity of ruminal degradable protein from soy proteins required for optimum protein synthesis of non-structural carbohydrate-fermenting microbes appears to be equivalent to 9.5% of dietary fermented OM.

• 한국수산과학회지
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• 제51권5호
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• pp.549-555
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• 2018

The objectives of this study were to confirm the nutritional requirements and improve the survival of the walleye pollock Theragra chalcogramma, a cold seawater fish, by enrichment. We analyzed the fatty acids and amino acids of fertilized pollock eggs before hatching, just-hatched larvae, larvae that had absorbed only the yolk sac, and larvae starved for 2 days after yolk absorption. For the survival improvement experiment, we administered docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and DHA-EPA enrichment. Fatty acid decreased DHA and EPA content. On the $30^{th}$ day, body growth was significantly greater in pollock given the EPA and DHA-EPA treatments (P<0.05). Larval survival at 20 and 30 days after hatching (DAH) was greatest under the DHA-EPA treatment (P<0.05). Survival was significantly lower under the EPA treatment at 10 DAH, but then increased to approach that seen under the EPA-DHA treatment (P<0.05). Therefore, we determined that reduced survival in hatchlings of high-mortality pollack could be improved by controlling EPA and DHA content during enrichment. We conclude that cold seawater fish must be given feed that meets their nutritional needs, which can be accomplished using newly manufactured enrichment products for the larvae of cold seawater fish, such as pollock.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1638-1652
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• 2000

Prolific females require better nutrition and feeding practice because of larger litter size and the substantial decline in body fat. Life-time pig output will be compromised if body protein and fat are not properly managed. First litter females are especially vulnerable because they can loose ${\geq}15%$ of whole-body protein. Conservation of body protein mass during first lactation minimizes wean to estrus interval and increases second litter size (up to 1.2 pigs). The ability to influence litter-size by amino acid nutrition is a new dimension in our understanding. A P2 fat depth below 12 mm at farrow and below 10 mm at wean compromised wean to estrus interval (>2 d) and next litter size (0.5 to 1.5 pigs) in sows. It is now clear that a 'modest' excess of feed during the first 72 h of pregnancy decreases embryo viability so that the potential for an increased litter size at birth is not realized. The capacity for milk production by prolific young sows is 25% higher than the standard used previously (NRC, 1988). First litter females averaged 9.82 kg milk/d for a 21 d lactation. Second and third litter counterparts averaged 10.35 kg/d. Milk production was 95% of peak by 10 d of lactation and sows were in greatest negative energy and lysine balance during the first 6 d. Nearly 45% of the total loss in body protein occurred within the first 6 d, but this could reduced to 30-35% by using a more aggressive feeding strategy after parturition. There appear to be 2 phases in lactation for lysine need (d 2-12 vs 12-21). Feeding to the higher level alleviates the second litter size decline. The lysine requirement for lactation can be predicted with accuracy, but we are not able to predict the second limiting amino acid. Mammary uptake of valine relative to lysine and recent work with practical diets suggest that the recent NRC (1998) pattern is realistic and that threonine and valine could be co-limiting for corn-soy diets for prolific sows nursing 10-11 pigs. Empirical studies are needed to refine the ideal pattern so that synthetic lysine can be used with more confidence. Milk fat output for the elite sow is extraordinary and poses an unnecessarily high energetic cost. Methods that reduce mammary fat synthesis will benefit the sow and may enhance piglet growth.

• Asian-Australasian Journal of Animal Sciences
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• 제12권5호
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• pp.799-805
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• 1999

This study was conducted to investigate the effects of L-carnitine with different levels of lysine on performance of pigs weaned at 21 days of age. A total of 120 pigs were allotted into a $3{\times}2$ factorial design with three different levels of lysine (1.40%, 1,60% and 1.80%) and two levels of L-carnitine (0 and 1,000 ppm). Each treatment had 4 replications with 5 pigs per replicate. Pigs of $22{\pm}1$ days (5.9 kg of body weight) were grouped into a completely randomized block design. Treatments were 1) 1.4-Crt; 1.40% of lysine with 1,000 ppm of L-carnitine, 2) 1.4-N; 1.40% of lysine without L-carnitine, 3) 1.6-Crt; 1.60% of lysine with 1,000 ppm of L-carnitine, 4) 1.6-N; 1.60% of lysine without L-carnitine, 5) 1.8-Crt; 1.80% of lysine with 1,000 ppm of L-carnitine and 6) 1.8-N; 1.80% of lysine without L-carnitine. Growth performance was optimized in pigs fed 1.6% lysine regardless of carnitine addition. For the first 7 days of the experimental period, the best ADG and F/G were found in pigs within the 1.6-Crt group. Carnitine significantly improved (p<0.05) ADG of pigs when the lysine level in the diet was 1.6%. Only in the third week carnitine had a significant influence on growth performance of pigs. A lysine-sparing effect of L-carnitine was not detected in this study. The 1.6-Crt group showed the best proximate nutrient digestibility, and the crude fat and gross energy digestibility were higher when the L-carnitine was added in the diet. Lysine level significantly affected the digestibilities of DM (p<0.001), GE (p<0.001), CP (p<0.01) and C.fat (p<0.05). Carnitine also significantly improved digestibility of nutrients. Lysine level as well as carnitine level affected the amino acids digestibility, however, in 1.8% lysine diet carnitine did not influence on amino acids digestibility. Plasma carnitine content was significant higher (p<0.05) in pigs fed L-carnitine. This indicates the increased biological availability of carnitine within the body. L-carnitine supplementation tended to improve feed utilization during the third week (p<0.10) and during the entire period (p=0.10). Lysine level significantly affected feed utilization of pigs during the third week and entire period (p<0.05). As pigs grew, the lysine requirement was reduced.

• 한국양식학회지
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• 제17권2호
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• pp.144-150
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• 2004

본 연구는 현재 국내 넙치 양식장에서 이용되고 있는 MP, DEP-1, DEP-2, DEP-3, FEP-1, FEP-2에 대해서 농림부에서 규정하고 성분규격 등록항목 외에 사료의 P/E ratio, POV, AnV, Totox, VBN, 총균수, 사료내 지방산 및 아미노산 조성과 그동안 이루어진 넙치 사료영양관련 연구결과를 바탕으로 비교 분석하여 국내 시판중인 넙치 사료의 품질을 평가하기 위해서 이루어졌다. 6가지 사료 모두 요구량 이상으로 단백질이 과잉첨가 된 것으로 생각되며 MP, DEP-1, DEP-2, FEP-1은 사료 내 지질 함량도 과잉첨가 된 것으로 나타났다. 그리고 PH ratio를 기준으로 볼때, MP와 FEP-2는 특히 단백질 함량이 과잉 첨가된 것으로 나타났으며, FEP-1는 특히 지방이 너무 많이 첨가된 것으로 판단된다. 그리고 MP가 배합사료에 비해 사료내 인 함량이 요구량 이상으로 과잉 첨가되어 있어 수질오염을 일으킬 가능성이 높은 것으로 판단된다. 지방산패 및 단백질 부패는 MP가 배합사료에 비해 높게 나타났으며, 이로 인한 문제가 발생할 가능이 높으며, 더욱더 취급 시에 보관 및 관리에 신경을 써야 될 것으로 생각된다. 그리고 지방산의 조성에 있어서는 DHA와 EPA 모두 MP가 배합사료보다 높게 나타났으며, 배합사료는 이에 대한 고찰이 필요할 것으로 생각된다. 사료 내 라이신 함량은 MP와 FEP-2가 요구량 수준으로 첨가되어 있는 것으로 생각되며, 그 외 사료들은 요구량 기준으로 라이신 함량이 부족할 가능성이 높기 때문에 추가첨가가 필요할 것으로 생각된다. 따라서, 농림부에서 양축용 사료 및 반추동물용 섬유질 배합사료의 성분등록을 축종과 사육시기별 품질관리 기준과 같이 양어용 배합사료의 특성을 고려하여 어종별, 크기별 품질관리 기준이 마련되어야 사료회사 및 양식업자가 배합사료에 대한 신뢰성을 회복하고, 이를 통하여 생사료에서 배합사료로 전환을 앞당길 수 있는 계기가 될 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.185-191
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• 1997

This experiment was conducted to determine the effects of a low-protein diet supplemented with DL-methionine plus L-cystine (Met + Cys) on the growth performance and fat accumulation of female broiler chicks during the growing period (3-6 wks old). A low-protein diet (17% CP; 3,200 ME kcal/kg) was supplemented with Met + Cys (1.1 : 1.0) at levels 0.75, 0.94, 1.25, 1.31 or 1.50% of diet, respectively. Another diet with 21% CP and 3,200 ME kcal/kg served as the control group. All essential amino acids were adjusted to meet the National Research Council (1984) requirement for chicks. Feed and water were given ad libitum. Body weight of the chicks fed the low-CP diets supplemented with Met + Cys were heavier than those of the control birds. Feed conversion ratio and feed intakes were not significantly different between and among the treatment groups. Similary, abdominal fat content was not significantly different among the various treatments except that of the chicks fed the low CP diet with 1.25% Met + Cys which was higher than that of the control group. Fatty acid synthetase (FAS), acetyl-CoA carboxylase (ACC) activities and carcass protein content were not influenced by dietary treatments. Carcass fat content was lowest in chicks fed low CP diet with 0.75% Met + Cys and highest in the group that received 1.50% Met + Cys supplementation. Liver triglyceride increased as Met + Cys supplementation level increased. Various lipid fraction concentrations (cholesterol ester, free cholesterol, and phospholipid) in the serum went up as Met + Cys increased up to 1.25% after which it levelled off. Results of this experiment suggest that it is possible to reduce dietary protein level from 21% to 17% for growing broiler chicks by the supplementation of Met + Cys when other EAA were sufficient.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.238-243
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• 2000

An exoinulinase (${\beta}-D-fructofuranosidase$) gene was cloned by chromosome walking along the upstream region of the endoinulinase gene of Pseudomonas mucidolens isolated from soil. the exoinulinase gene consisted of an ORF of 0,506 bp encoding a polypeptide of 501 amino acids with a deduced molecular weight of 55,000. The exoinulinase produced by the recombinant Escherichia coli $DH5{\alpha}$ strain was also purified to homogeneity as determined by SDS-PAGE and a zymogram. The molecular weight of the purified exoinulinase according to both SDS-PAGE and gel filtration matched the deduced molecular weight of the protein described above, thereby indicating that the native form of the exoinulinase was a monomer. The purified enzyme hydrolyzed activity value of 2.0. Furthermore, no inulo-oligomers were liberated from the inulin substrate in the enzymatic reaction mixtures incubated for 90 min at $55^{\circ}C$. Taken together, these results indicate that the purified ${\beta}-D-fructofuranosidase$ was an exoinulinase. The pH and temperature optima of the exoinulinase were pH 6.0 and $55^{\circ}C$, respectively. the enzymehad no apparent requirement for a cofactor, and its activity was completely inactivated by $Ag^{+},{\;}Hg^{2+},{\;}and{\;}Zn^{2+}$. Kinetic experiments gave $K_m,{\;}V_{max},{\;}and{\;}K_{cat}$ values for inulin of 11.5 mM, 18 nM/s, and $72{\;}s^{-1}$, respectively. the exoinulinase was fairly stable in broad pH conditions (pH 5-9), and at pH 6.0 it showed a residual activity of about 70% after 4 h incubation at $55^{\circ}C$.

• 한국식품과학회지
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• 제8권4호
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• pp.263-272
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• 1976

According to the intercombined review of chemical and biological investigation it has been noted that the metabolizable energy per gram dietary protein of mixed diet of daily intake patterned by Korean population has been found 3.4-3.6 Cal., which entails 10-12% level of the protein calorie percentage of total metabolizable energy, the biological value being fallen within the scope 63-73. The structure of dietary protein has revealed that the lysine and isoleucine were primary limiting amino acids and threonine secondary limiting as a general trend, however, it is assumed that the ultimate nutritional effect of dietary protein might be restricted uniformly among regions by the amount of lysine, since the lysine availability has been yielded as low as 72-82% level. As for the net protein utillization NPUst falls in the range of 52-62 and the NPUop 47-58. In either part the mountainous region has demonstrated lowest value and the urban area highest, these trend being obviously associated with the ratio of animal protein relative to the vegetable origin. The net dietary protein calorie percentage (NDpCal %) has been found within the range of 5-7 that may be capable of meeting the requirement for the maintenance of adult, though for the growth it is insufficient. Present level of total caloric intake would not influence on the fate of protein value of prevailing regional diet in terms of caloric restriction, since the present intake of food energy is higher than the lower limit of caloric intake that would impair the biological performance of dietary protein fed ad libitum basis. Based on the protein efficiency, the adequacy of current level of protein intake was analyzed in terms of utilizable protein, and it has been demonstrated that the 37.8g of utilizable protein in the fishery region and 38.2g in the mountainous region were bellow the FAO recommendation. Accordin to the hematological study it may be interpreted that the anemic symptoms of the mountainous region has some possibility of being related to the inferior status of dietary protein in quality as well as in quantity.

• Journal of Nutrition and Health
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• 제26권9호
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• pp.1033-1048
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• 1993

This study was designed to describe the effect of the protein quality at different intake level of protein on the protein metabolism in the whole body of growing pigs with a simulation model. Varying to the protein level in feeds, four simulations were conducted. The feed protein level, represented as proportions of digestible protein to the metabolic energy (DP/ME, g/MJ), were 6-8, 11-13, 17-19, and 23-25 DP/ME, respectively. Two protein quality and six weeks of growth time were used at each simulation. The objective function for the simulations was protein deposition in the whole body, which was calculated from the experimental results. The parameters in the simulation were determined by the parameter estimation technique. The results obtained from the simulation were as follows: The protein synthesis and breakdown rates(g/day) in the whole body was increased with the increase of protein quality only at lower or required level of protein intake. They showed a parallel behavior in the course of growth, irrespective of quality and level of feed protein intake. The simulated protein deposition and protein synthesis showed a linear relationship between them at different protein quality and level. The affinity parameter showed a linear relationship between them at different protein quality and level. The affinity parameter showed that arginine, tryptophan and isoleucine were more efficient in the stimulation ofbody protein synthesis. Lysine and phenylalanine+tyrosine were less efficient. The oxidation parameter showed that histidine, pheyalanine+tyrosine were less efficient. The oxidation parameter showed that histidine, phenyalanine+tyrosine, and methionine+cystine were oxidized in larger magnitude than lysine and threonine. The oxidation parameter of most amino acids increased with the increase of protein intake beyond the requirement level, but not any more at highest protein intake level. Finally it was found that the improvement of feed protein quality at the lower or required level of protein intake increase protein deposition through a parallel increase of protein synthesis and breakdown.