• Journal of Nutrition and Health
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• 제31권5호
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• pp.897-905
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• 1998

Docosahexaenoic acid(DHA), a $\omega$3 series fatty acid and arachidonic acid(AA). a $\omega$6 series fatty acid were found in relatively high concentrations in the phospholipids(PLs) of cell membranes of nerve tissues, and they can be affected by various factors. The present study examined the effects of dietary $\omega$6 and $\omega$3 fatty acid composition on P/M/S and on $\omega$3/$\omega$6 fatty acid ratios in brain PLs of 2nd generation rats. The expeimental diets consisted of 10% fat(by wt), which were computer- searched mixed oil('M') with P/M/S ratio, 1 : 1.4 : 1 and $\omega$6/$\omega$3 ratio, 6 : 1 and safflower oil('S') poor in $\omega$3 fatty acids. The experimental diets were started 3-4 wks prior to conception. During the lactation period, the feeding mothers were switched 1 wk after birth and provided the pups for 2 wks with milk which had compositions different from that of their natural mother. The same diet as their mothers was provided from weaning to 9 wks of age. The 'M'and 'S' rats were again subdivided into MM, MS, SS, SM rats according to diet which their lactating mothers were fed from the begining of the experiment. The relative percentage of P/M/S fatty acids in brain PLs in all experimental groups converged to a very similar value at 9 wks of age, indicating the existence of a control mechanism for the degree of fatty acids, unsaturation. The $\omega$3/$\omega$6 fatty acid ratios of brain PLs converged to about 1.0 in MM & SM groups and to 0.7 in SS & MS groups, suggesting also the existence of some balance between $\omega$3 and $\omega$6 fatty acids in developing rat brain. The concentrations of $\omega$3 fatty acids, especially DHA, in the SM group were increased and became similar to those in MM group at 9 wks of age. The increase in DHA of brain PLs was counterbalanced b)r a decrease in 22 5$\omega$6. Therefore, the ratios of 22 : 6$\omega$6/22 : 5$\omega$6 were higher in both MM & SM groups than those of SS & MS groups at 9 wak of age. Although dietary $\omega$3 and $\omega$6 fatty acids affected 22 : 6$\omega$S and 22 : 5$\omega$6 contained in rat brain PLs reciprocally, the relative percentage of AA did not appear to be significantly influenced by the diet in all groups at 9 wks of age, suggesting that a mechanism for the maintenance of a certain level of AA in brain PLs exists. In conclusion, the $\omega$3/$\omega$6 fatty acid and 22 : 6$\omega$3/22 : 5$\omega$6 ratios, but not P/M/S ratio, of rat brain PLs were affected by the postnatal dietary changes. Futher studies are required to clarify the mechanism(S) of ensuring a certain level of DHA and of maintaining a similar level of AA in rat brain PLs after. weaning(9 wk) regardless of prenatal and postnatal dietary changes. (Korean J Nutrition 31(5) : 897-905, 1998)

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.992-1000
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• 2005

Campylobacter is one of the emerging foodborne pathogens, and its worldwide incidence rate is extremely high. This study was undertaken to isolate and identify Campylobacter strains from chicken carcasses in the local markets, and analyze their characteristics regarding oxygen tolerance. They were isolated after aerobic enrichment and identified by biochemical, physiological, and morphological characteristics, PCR, and 16S rDNA sequencing. Their oxygen tolerances were analyzed in terms of the cell surface hydrophobicity, cell fatty acid composition, and oxidoreductase. Five strains of C. jejuni were isolated and identified from 61 isolates from 50 chickens. Among them, C. jejuni IC21 grew well in Brucella broth and commercial milk under aerobic condition. However, in the aerobic exposure, the cell surface hydrophobicity of C. jejuni IC21 was almost the same as the other isolates, even though its morphology changed from the spiral-bacilli form into the coccoid form. Fatty acid analyses showed that all Campylobacter strains had a high composition of $C_{19:1}$, cyclopropane fatty acid, and that the amount of the other fatty acids were very similar between them. Interestingly, however, only oxidoreductase activities of C. jejuni IC21 increased highly under aerobic exposure even though its activities were almost the same as the other C. jejuni strains just after microaerobic culture. It had 11.8 times higher catalase activity, 4.4 times higher for SOD, and 2.0 times higher for NADH oxidase activities. Therefore, in the case of the aero-adaptive C. jejuni IC21, expression of oxidoreductase significantly increased under oxidative stressed condition, which might allow it to survive for a longer time and grow on food under aerobic exposure. Such new strain might be one of the explanations for the increase of campylobacteriosis.

• 한국식품영양과학회지
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• 제33권10호
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• pp.1626-1633
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• 2004

$\omega$3계 지방산이 부족한 50군과 P/M/S 및$\omega$6/$\omega$3비율이 적절한 MO군으로 생후 9주까지 사육한 흰쥐의 적혈구와 뇌조직의 시냅토솜, 미토콘드리아 및 마이크로솜내 oleic acid 조성 비율은 생후 3주에는 두 군간에 유의한 차이를 보이지 않고 일정한 수준으로 유지되는 것으로 나타났으나 생후 9주에는 MO군에서 SO군보다 높게 나타났다. 실험식이내 oleic ac:인 조성은 SO군이 MO군보다 매우 낮으나, SO군의 모유에서 oleic acid 조성비율이 식이에 비해 크게 증가된 것으로 나타나, 모유가 뇌 성장$.$발달기간중의 뇌조직내 oleic acid의 주요 급원이 될 수 있음을 나타내주고 있다. 18:0에서 oleic acid의 de novo 합성 정도를 나타내는 간접지표인 -9 desaturation index는 생후 3주에는 실험군간(시냅토솜 예외)에 유의한 차이를 보이지 않았으나, 생후 9주에는 식이내 oleic acid가 풍부한 MO군의 시냅토솜에서 높게 나타났다. 한편 생후 9주 마이크로솜 분획 에서 olelc acid 수준은 실험군 간에 차이를 보이지 않았으나, -9 desaturation index는 SO군에서 MO군보다 높아 뇌조직 에서 oleic acid가 생합성될 수 있음을 간접적으로 설명 해주고 있다. 따라서 흰쥐 뇌조직의 oleic acid는 식이와 모유 등의 이미 합성된 oleic acid가 뇌로 우선적으로 유입되는 부분과 뇌조직 자체에서 합성되는 부분에 의한다고 생각된다. 그러나 식이중 oleic acid가 부족하면 뇌 세포분획내의 oleic acid수준이 유의하게 감소하였으므로, 식이중 적절한 수준의 oleic acid가 정상적인 뇌발달에 필수적임을 다시 한번 강조하게 한다. 

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1466-1472
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• 2008

Variations in conjugated linoleic acid (CLA) concentrations in Holstein dairy cows milk, depending on feeding systems in different seasons was investigated. Milk samples were collected from Holstein dairy cows, which either grazed for whole days (WG), only daylight hours (TG), or were offered a total mixed ration (TMR) and experienced no grazing (NG), from April to December of 2005. In April, November and December, the cows in TG and WG treatments received grass silage and some concentrate, while from May to October, the cows grazed on temperate pasture. The cows in NG treatment received the TMR throughout the season. The major fatty acid obtained in the pastures was linolenic acid. There was no significant difference in the pasture's linolenic acid concentrations from May to September, but there was a significant decrease in October. However, the linolenic acid concentrations obtained in the pasture were always much higher than those obtained from the TMR. Linoleic acid was also the major fatty acid in the TMR, but these concentrations were higher in the TMR than in the pasture. There was no significant difference in milk cis9trans11CLA (c9t11CLA) concentrations between the three feeding systems while the cows were fed on conserved pasture in April, November and December. Although c9t11CLA concentrations were lower in the TMR, it was found that the cows which grazed in fresh pasture experienced significantly higher concentrations of c9t11CLA in their milk than those which received only TMR. It was also found that cows in the WG treatment experienced higher c9t11CLA concentrations than those in the TG treatment. In the WG and TG treatments, c9t11CLA concentrations were highest in June, after which, they gradually decreased (p<0.01) until October. For the NG treatment, there was no significant change in the concentrations of c9t11CLA (p>0.05) with season. Overall, trans11C18:1 and c9t11CLA were greatly influenced by season, with higher variation in the WG treatment than in the TG treatment and no variation in the NG treatment.

• 생명과학회지
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• 제19권9호
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• pp.1258-1264
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• 2009

본 연구에서는 건조하지 않은 감귤부산물을 첨가한 TMR사료를 홀스타인 젖소에게 급여하고 생산한 원유의 성분 특성에 미치는 영향을 검토하였다. 초산우와 경산우를 대상으로, 감귤부산물 TMR사료를 급여하지 않은 젖소의 원유를 T0구, 그리고 감귤부산물 TMR사료를 급여한 젖소의 원유를 T1구이라 하였으며, 각각 7 마리의 젖소에서 착유한 원유의 분석치를 1반복으로 하고, 3반복 실행하였다. 초산우 및 경산우 모두 원유의 수분, 조단백질, 조지방, 조회분 함량 및 열량은 T0구 및 T1구 사이에 유의적 차이가 없었다. 원유의 콜레스테롤 함량은 초산우 및 경산우 모두 T0구보다 T1구가 낮게 나타났으며 경산우의 경우 T1구가 유의하게 낮은 값을 보였다(p<0.05). 원유의 무기질 함량은 초산우의 경우 Na와 S, 경산우의 경우 Na, Cu, Fe 및 S가 T1구에서 유의하게 높게 나타났다. 초산우와 경산우 모두 T0구 및 T1구의 구성아미노산 총량, 포화지방산과 불포화지방산의 조성비, 그리고 모든 유리 지방산의 조성비는 유의적 차이를 보이지 않았다. 초산우와 경산우 원유의 비타민 A, E, $B_1$, $B_2$ 및 $\beta$-carotene 함량 중 초산우의 비타민 $B_1$은 T0구보다 T1구가 유의적으로 많고(p<0.05), 나머지는 유의적 차이가 나타나지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8_spc호
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• pp.1296-1305
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• 2019

There have been recent advances concerning research of the feeding and nutrition of dairy goats in a wide array of areas. Ruminally emitted methane and supplementary feedstuffs to a lesser extent make appreciable contributions to the carbon footprint of dairy goats, with the former affected by type of production system and associated dietary characteristics. Unique behavior of goats necessitates careful consideration of the nature of confinement facilities to achieve optimal production by animals differing in social hierarchy. Physiological conditions such as nutritional needs and perhaps health status may influence diet selection by goats in both grazing and confinement settings. Some research suggests that low concentrations of protein and fat in milk of high-yielding dairy goat breeds could involve the type and nature of dietary ingredients as influencing end products of ruminal fermentation. With the relationship between milk urea nitrogen concentration and efficiency of dietary protein utilization, through future research the measure may be a useful tool for diet formulation as in dairy cattle. Effects of dietary inclusion of sources of fats and oils vary considerably depending on their nature, as is also true for byproduct feedstuffs and conventional ones being substituted for. Supplementation of dairy goats with sources of polyunsaturated fatty acids can affect oxidative stress and various feedstuffs influence antioxidant status; however, research addressing the significance of such changes under practical production settings would be beneficial.

• 식품과학과 산업
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• 제51권2호
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• pp.148-156
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• 2018

Structured lipids are lipids in which the composition and/or positional distribution of fatty acids have been chemically or enzymatically modified from their natural biosynthetic form. Because structured lipids have desired nutritional, physicochemical, textural or physiological properties for applications in processed foods, functional foods, or nutraceuticals, many research activities have been aimed at their commercialization. The enzymatic production of structured lipids using lipases as the biocatalysts has a big potential in the future market due to the specificity or selectivity of the lipases. This article introduced some examples of specialty structured lipids that have been enzymatically produced and have been utilized as commercialized products. The commercialized products include medium- and long-chain triacylglycerols, human milk fat substitutes, cocoa butter equivalents, trans-free plastic fats, low-calorie fats/oils, and health-beneficial fatty acid-rich oils.

• Animal Bioscience
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• 제34권9호
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• pp.1466-1478
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• 2021

Objective: Ruminants are completely dependent on their microbiota for rumen fermentation, feed digestion, and consequently, their metabolism for productivity. This study aimed to evaluate the rumen bacteria of lactating yaks with different milk protein yields, using high-throughput sequencing technology, in order to understand the influence of these bacteria on milk production. Methods: Yaks with similar high milk protein yield (high milk yield and high milk protein content, HH; n = 12) and low milk protein yield (low milk yield and low milk protein content, LL; n = 12) were randomly selected from 57 mid-lactation yaks. Ruminal contents were collected using an oral stomach tube from the 24 yaks selected. High-throughput sequencing of bacterial 16S rRNA gene was used. Results: Ruminal ammonia N, total volatile fatty acids, acetate, propionate, and isobutyrate concentrations were found to be higher in HH than LL yaks. Community richness (Chao 1 index) and diversity indices (Shannon index) of rumen microbiota were higher in LL than HH yaks. Relative abundances of the Bacteroidetes and Tenericutes phyla in the rumen fluid were significantly increased in HH than LL yaks, but significantly decreased for Firmicutes. Relative abundances of the Succiniclasticum, Butyrivibrio 2, Prevotella 1, and Prevotellaceae UCG-001 genera in the rumen fluid of HH yaks was significantly increased, but significantly decreased for Christensenellaceae R-7 group and Coprococcus 1. Principal coordinates analysis on unweighted UniFrac distances revealed that the bacterial community structure of rumen differed between yaks with high and low milk protein yields. Furthermore, rumen microbiota were functionally enriched in relation to transporters, ABC transporters, ribosome, and urine metabolism, and also significantly altered in HH and LL yaks. Conclusion: We observed significant differences in the composition, diversity, fermentation product concentrations, and function of ruminal microorganisms between yaks with high and low milk protein yields, suggesting the potential influence of rumen microbiota on milk protein yield in yaks. A deeper understanding of this process may allow future modulation of the rumen microbiome for improved agricultural yield through bacterial community design.

• Animal Bioscience
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• 제36권10호
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• pp.1536-1545
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• 2023

Objective: The objective was to evaluate the effects of UV-B irradiated vitamin D-enriched yeast supplementation on milk yield, milk composition, vitamin D in milk, milk fatty acids, blood chemistry, and 25(OH)D status in dairy cows. Methods: Six Thai Friesian cows (milk production, 11.2±2.0 kg/d; body weight, 415.0±20.0 kg; and days in milk, 90.0±6.0) were allocated to each treatment in a 3×3 Latin square design, with three treatments and three periods. Each period of the Latin square lasted 49 days consisting of 14 days for diet adaptation and 35 days for sample collection. Dairy cows were randomly assigned to one of three treatments: i) feeding a basal diet without yeast (CON); ii) basal diet + 5 g of live yeast (75 IU/head/d of vitamin D₂; LY); and iii) basal diet + 5 g of UV-B irradiated vitamin D enriched yeast (150,000 IU/head/d of vitamin D₂; VDY). Feed intake and milk production were recorded daily, milk sample collection occurred on days 14 and 35 of each collection period, and blood plasma was collected on days 0, 7, 14, 21, 28, and 35 of each collection period. Results: The results show that after a trial period of 14 and 35 days, the VDY group had significantly higher vitamin D content in milk than the LY and CON groups (376.41 vs 305.15, 302.14 ng/L and 413.46 vs 306.76, 301.12 ng/L, respectively). At days 7, 14, 21, 28, and 35 of the experiment, cows fed the VDY group had significantly higher 25(OH)D₂ status in blood than the CON and LY groups (51.07 vs 47.16, 48.05 ng/mL; 54.96 vs 45.43, 46.91 ng/mL; 56.16 vs 46.87, 47.16 ng/mL; 60.67 vs 44.39, 46.17 ng/mL and 63.91 vs 45.88, 46.88 ng/mL), respectively. Conclusion: In conclusion, UV-B irradiated vitamin D-enriched yeast supplementation could improve vitamin D content in the milk and 25(OH)D status in dairy cows during the lactation period.

• 한국식품영양과학회지
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• 제40권9호
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• pp.1256-1264
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• 2011

시중에 유통되고 있는 조제분유의 지방산 및 TAG 조성을 알아보기 위하여 국내외 조제분유 총 11 품목을 선정하였고, Folch법을 이용하여 지방을 추출한 다음 총 지방산과 sn-2 위치의 지방산 및 silver ion HPLC를 이용한 단일불포화-포화-단일불포화 glycerol(MSM)의 조성을 분석하였다. 조제분유의 조지방의 함량은 17.21~23.51%이었고, 특히 K5의 조지방 함량이 23.51%로써 분석된 조제분유들 중에서 가장 높게 나왔으나, K1은 17.21%의 함량을 보이면서 가장 낮게 나타났다. 분석된 조제분유들의 주요 포화지방산은 lauric acid(C12:0), myristic acid(C14:0), palmitic acid(C16:0), stearic acid(C18:0)이었다. Lauric acid의 함량은 K5와 K6에서 19.49%와 23.34%로 분석되어 15%보다 높은 함량을 나타냈다. 한편, 분석된 조제분유의 palmitic acid의 함량은 7.59~21.65%의 범위로써 K2, K3, K6, F1에서 각각 14.64%, 8.29%, 13.47% 및 7.59%로써 낮은 함량을 나타냈다. 불포화 지방산들 중에서 단일불포화지방산(C14:1, myristoleic acid; C16:1, palmitoleic acid; C17:1, heptadecenoic acid; C18:1, oleic acid; C18:1t, elaidic acid)의 함량은 20.23~45.07%로 나타났고, 단일불포화지방산들 중에서 대부분을 구성하고 있는 지방산은 oleic acid(C18:1)이었다. 분석된 조제분유에서 oleic acid의 함량은 19.64~44.64%의 범위였고 총 다가불포화지방산은 19.08~29.67%의 범위였다. Omega-6 다가불포화지방산과 omega-3 다가불포화지방산의 주요한 지방산은 필수지방산인 linoleic acid(C18:2)와 linolenic acid(C18:3, n-3)로 분석된 조제분유의 비율은 10:1~13:1로, 조제분유의 지방산 조성에 대한 지표인 linoleic acid/linolenic acid의 비율인 5:1~15:1 범위 내였다. 분석한 조제분유들 중에서 sn-2 위치에서의 lauric acid 함량은 7.70~52.09%로 나타났고, myristic acid의 함량은 3.15~20.89%로써 분석된 조제분유들은 전반적으로 sn-2 위치에서의 lauric acid 함량이 20% 이상으로 높게 나타났다. 특히, 분석된 조제분유들의 sn-2 위치에 존재하는 palmitic acid의 함량은 1.84~38.74%의 범위로써 K8과 F3이 각각 38.55%와 38.90%의 높은 함량을 나타냈다. 따라서 대부분의 국내외 조제분유들을 구성하는 triacylglycerol(TAG)의 sn-2 위치에서의 palmitic acid 함량이 모유와 비교하였을 때 낮은 경향을 보임을 알 수 있었다. 이러한 조제분유보다 더 나아가 HPLC 분석을 통해서 모유의 주요 TAG 형태라고 할 수 있는 단일불포화-포화-단일불포화 glycerol(MSM)의 함량이 외국의 조제분유인 F3이 가장 높게 나타났다. 따라서 조제분유에 이러한 MSM 형태의 지방 함량을 높여야하며, MSM 형태의 모유대체지 연구를 산업화하려는 노력이 필요하다.