• 한국식품과학회지
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• 제20권6호
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• pp.762-768
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• 1988

우유의 지방분해 효소인 리파제를 분리 연구하기 위하여 홀몬처리 되지 않은 정상유와 홀몬 처리된 비정상유에서 리파제를 Heparin-Sepharose-CL-6B를 이용하여 분리 정제하였다. Heparin-Sepharose에 친화력을 조사한 결과 두 개의 효소활성이 있는 성분이 구분되었으며 한 성분은 Heparin-Sepharose-CL-6B에 결합되었고 다른 한 성분은 결합되지 않은 채 분리되었다. 친화성 크로마토그램에 결합되어 분리 정제된 리파제의 최적 온도, 최적 pH, 기질 특이성, 분자량 및 BSA의 활성제로서의 작용등 여러 가지 효소특성은 모두 동일한 것으로 나타났다. 그러나 홀몬처리된 소에서 얻은 우유의 경우에는 또 다른 호소활성 성분이 나타나 있음을 알았다. 이 lipolytic activity가 있는 성분은 Heparin-Sepharose-CL-6B에 친화력을 보이지 않았으므로 정상적인 milk lipase와는 구별된다. 따라서 홀몬처리된 소에서 얻은 우유에 함유된 성분중 Heparin-Sepharose에 결합된 효소는 유지방 자동산화에 영향을 끼치지 않으며 Heparin-Sepharose에 결합되자 않은 활성이 있는 성분은 자동산패에 영향을 크게 미친다고 볼 수 있다. 그 이유는 hormone의 불균형 상태로 인하여 생유에 자동산패가 일어날 수 있으며 이것은 비정상적으로 분비된 리파제 출현 사이에 연관관계가 있음을 의미한다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.79-90
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• 2020

Objective: In the present study, an liquid chromatography/mass spectrometry (LC/MS) metabolomics approach was performed to investigate potential biomarkers of milk production in high- and low-milk-yield dairy cows and to establish correlations among rumen fluid metabolites. Methods: Sixteen lactating dairy cows with similar parity and days in milk were divided into high-yield (HY) and low-yield (LY) groups based on milk yield. On day 21, rumen fluid metabolites were quantified applying LC/MS. Results: The principal component analysis and orthogonal correction partial least squares discriminant analysis showed significantly separated clusters of the ruminal metabolite profiles of HY and LY groups. Compared with HY group, a total of 24 ruminal metabolites were significantly greater in LY group, such as 3-hydroxyanthranilic acid, carboxylic acids, carboxylic acid derivatives (L-isoleucine, L-valine, L-tyrosine, etc.), diazines (uracil, thymine, cytosine), and palmitic acid, while the concentrations of 30 metabolites were dramatically decreased in LY group compared to HY group, included gentisic acid, caprylic acid, and myristic acid. The metabolite enrichment analysis indicated that protein digestion and absorption, ABC transporters and unsaturated fatty acid biosynthesis were significantly different between the two groups. Correlation analysis between the ruminal microbiome and metabolites revealed that certain typical metabolites were exceedingly associated with definite ruminal bacteria; Firmicutes, Actinobacteria, and Synergistetes phyla were highly correlated with most metabolites. Conclusion: These findings revealed that the ruminal metabolite profiles were significantly different between HY and LY groups, and these results may provide novel insights to evaluate biomarkers for a better feed digestion and may reveal the potential mechanism underlying the difference in milk yield in dairy cows.

• 생명과학회지
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• 제25권1호
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• pp.75-83
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• 2015

강황 (Curcuma longa L.)은 건강기능성 식품의 훌륭한 소재로 전통적인 약용식물이다. 강황의 주요성분인 안토시아닌계인 curcumin은 항균작용, 항암작용, 항산화작용 등 다양한 효능이 있는 것으로 알려져있다. 본 연구는 혼합유산균을 스타터로 사용하여 강황 분말을 첨가한 발효유를 제조하여 발효유의 이화학적 특성 및 항염증 활성을 연구하였다. 발효유의 발효특성은 대조군에 비해 강황 첨가군에서 유산균의 성장이 현저히 빠르게 나타나 pH는 감소되었고 산도는 증가하였다. 또한 우유단백질의 분해도 부분적으로 일어났고 유기산은 lactic acid와 acetic acid가 높게 생성되었다. 기호도는 강황 특유의 쓴맛과 강한 향으로 인해 대조군에 비해 낮았다. 강황 발효유 배양액을 처리한 RAW 264.7 세포주에서 세포독성의 영향은 나타나지 않았다. 염증성 싸이토카인으로 TNF-${\alpha}$와 IL-6는 강황 처리군이 대조군에 비해 현저히 강하게 발현되었다. 또한 NO의 생성은 강황 처리군이 대조군에 비해 현저히 높았다. 이러한 연구결과는 강황 첨가가 유산균의 성장을 촉진시켜 발효유 제조에 도움을 주고, 염증활성을 조절하므로 강황을 이용한 발효유, 음료 제품 및 다양한 기능성 식품 소재로 활용할 수 있는 가능성을 시사하고 있다.

• 한국축산시설환경학회지
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• 제20권2호
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• pp.63-68
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• 2014

Environmental heat stress by global warming has a severe effect on the productivity of livestock and, in particular, on that of dairy cattle. Heat stress during high temperature environment directly and indirectly affects milk yield, milk quality and physiological response. This study was conducted to investigate the effects of heat stress on productivity and physiological responses of livestock. Temperature-humidity data logger were established inside the feedlot for measuring real time changes in the feedlot environment. Milk was collected every day for analysing the productivity of dairy cattle. Blood sample and respiration of dairy cattle were collected once in a week for investigating the physiological response factors. Blood component concentration associated with lipolysis metabolism and milk production showed change during tropical night period. Temperature humidity index (THI) of a specific location inside the feedlot showed continuously high levels.

• Journal of Nutrition and Health
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• 제53권5호
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• pp.445-451
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• 2020

Purpose: Breastfeeding is the optimal method for feeding a newborn. But insufficient breast milk is the major reason why mothers give up breastfeeding. Herbal galactagogues have been used increasingly to treat postpartum hypogalactia. This study examined the effect of an herbal tea containing Chrysanthemum indicum, as the main ingredient, on milk production in lactating rats. Methods: The herbal tea contained C. indicum (27%), Foeniculum vulgare Mill (21%), Pimpinella anisum (18.2%), Carum carvi (16.1%), Urtica dioica (14.7%), and Gardenia jasminoides (3%). Sixteen lactating Sprague-Dawley (SD) rats were divided randomly into 2 groups, the normal control group (NC; n = 8), and the galactagogue herbal tea group (GHT; n = 8) for 7 days. Lactating rats were administered the decoction of an herbal galactagogue mixture by oral gavage or the same amount of distilled water and milk production was assessed by measuring the pups' weights during the suckling period. The blood concentrations of prolactin, cortisol, oxytocin levels and mammary gland tissues were examined to assess the effects of the galactagogue. Results: Milk production was 9.2% higher in the GHT group given the herbal tea than in the NC group and the difference was statistically significant. The cortisol level in the GHT group was 17.2% higher than the NC group. The herbal tea containing C. indicum increased the size of the alveoli epithelium cells and the mammary lobe. Conclusion: The present study revealed the potential of herbal tea containing C. indicum to enhance milk production in postpartum SD rats.

• 한국축산식품학회지
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• 제34권3호
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• pp.316-324
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• 2014

Milk fat is an important food component, and plays a significant role in the economics, functional nutrition, and chemical properties of dairy products. Dairy products also contain nutritional resources and essential fatty acids (FAs). Because of the increasing demand for dairy products, milk fat is a common target in economic fraud. Specifically, milk fat is often replaced with cheaper or readily available vegetable oils or animal fats. In this study, a method for the discrimination of milk fat was developed, using FAs profiles, and triacylglycerols (TGs) profiles. A total of 11 samples were evaluated: four milk fats (MK), four vegetable oils (VG), two pork lards (PL), and one beef tallow (BT). Gas chromathgraphy analysis were performed, to monitor the FAs content and TGs composition in MK, VG, PL, and BT. The result showed that qualitative determination of the MK of samples adulterated with different vegetable oils and animal fats was possible by a visual comparision of FAs, using C14:0, C16:0, C18:1n9c, C18:0, and C18:2n6c, and of TGs, using C36, C38, C40, C50, C52, and C54 profiles. Overall, the objective of this study was to evaluate the potential of the use of FAs and TGs in the detection of adulterated milk fat, and accordingly characterize the samples by the adulterant oil source, and level of adulteration. Also, based on this preliminary investigation, the usefulness of this approach could be tested for other oils in the future.

• Asian-Australasian Journal of Animal Sciences
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• 제10권4호
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• pp.335-356
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• 1997

Injection of bovine growth hormone (bGH) to lactating dairy cows increases milk yield and yields of milk components including fat. It is generally believed that most of the anabolic effects derived from bGH in animal tissues are primarily mediated by IGF-1. IGF-1 is a strong anabolic peptide in the plasma of animals and exerts mitogenic and metabolic effects on target cells. Contrary to most protein hormones, the majority of IGF-1 in circulation is bound to the binding proteins (IGFBPs) which are known to be responsible for modifying the biological actions of IGF-1, thus making determinations of IGF-1 actions more difficult. On the other hand, fat is a major milk component and the greatest energy source in milk. Currently, the fat content of milk is one of the major criteria used in determining milk prices. It has been known that flavor and texture of dairy products are mainly affected by milk fat and its composition. Acetyl-CoA carboxylase (ACC) is the rate limiting enzyme which catalyzes the conversion of acetyl-CoA to malonyl-CoA for fatty acid synthesis in 1ipogenic tissues of animals including bovine lactating mammary glands. In addition to the short-tenn hormonal regulation of ACC by changes in the catalytic efficiency per enzyme molecule brought about by phosphorylation and dephosphorylation of the enzyme, the long-term hormonal regulation of ACC by changes in the number of enzyme molecules plays an essential role in control of ACC and lipogenesis. Insulin, at supraphysiological concentrations, binds to IGF-1 receptors, thereby mimicking the biological effects of IGF-1. The receptors for insulin and IGF-1 share structural and functional homology. Furthermore, epidermal growth factor increased ACC activity in rat hepatocytes and adipocytes. Therefore, it can be assumed that IGF-1 mediating bGH action may increase milk fat production by stimulation ACC with phosphorylation (short term) and/or increasing amounts of the enzyme proteins (long term). Consequently, the main purpose of this paper is to give the readers not only the galactopoietic effects of bGH, but also the insight of bGH action with regard to stimulating milk fat synthesis from the whole body to the molecular levels.

• Journal of Animal Science and Technology
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• 제63권3호
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• pp.475-490
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• 2021

An experiment was conducted to determine the effects of two levels of rumen undegradable protein (RUP) without or with whole or extruded flaxseed on milk yield, milk component, milk fatty acids (FAs) profile and plasma metabolites in transition ewes. Three weeks before and after lambing, seventy-two Baluchi ewes were used in a completely randomized design with a 3 × 2 factorial arrangement of treatments. The treatments contained 1) no flaxseed + 20% RUP (no flaxseed, low RUP [NFLR]); 2) no flaxseed + 40% RUP (no flaxseed, high RUP [NFHR]); 3) 10% whole flaxseed + 20% RUP (whole flaxseed, low RUP [WFLR]); 4) 10% whole flaxseed + 40% RUP (whole flaxseed, high RUP [WFHR]); 5) 10% extruded flaxseed + 20% RUP (extruded flaxseed, low RUP [EFLR]), and 6) 10% extruded flaxseed + 40% RUP (extruded flaxseed, high RUP [EFHR]). Ewes fed 10% extruded flaxseed exhibited higher (p < 0.001) dry matter intake (DMI) and colostrum yield (p < 0.1) compared to other treatments. Two types of flaxseed and RUP levels had no significant effect on milk yield, but milk fat and protein contents decreased and increased in diets containing 40% RUP, respectively. Ewes fed extruded flaxseed produced milk with lower concentrations of saturated fatty acids (SFA) and higher α-linolenic and linoleic acids and also polyunsaturated fatty acids (PUFA) compared to other groups (p < 0.05). During post-lambing, the ewes fed diets containing flaxseed exhibited higher concentration of serum non-esterified FAs (NEFA) compared to diets without flaxseed (p < 0.01). The concentration of serum β-hydroxybutyric acid (BHBA) decreased in the diets containing flaxseed types at pre-lambing, but increased in diets containing extruded flaxseed at post-lambing (p < 0.01). The serum glucose concentration of ewes (pre and post-lambing) which consumed diets containing extruded flaxseed or 40% RUP increased, but blood urea concentration was elevated following supplementation of diet with whole flaxseed or 40% RUP (p < 0.001). In conclusion, utilization of 10% extruded flaxseed in the diets of transition ewes had positive effects on animal performance with favorable changes in milk FAs profile. However, there is no considerable advantage to supply more than 20% RUP level in the diet of transition dairy sheep.

• Animal Bioscience
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• 제36권1호
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• pp.132-143
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• 2023

Objective: The aim was to study the influence of cooling milk at 9℃ at the farm versus keeping it at 20℃ on Parmigiano Reggiano cheese lipolysis. Methods: A total of six cheesemaking trials (3 in winter and 3 in summer) were performed. In each trial, milk was divided continuously into two identical aliquots, one of which was kept at 9℃ (MC9) and the other at 20℃ (MC20). For each trial and milk temperature, vat milk (V-milk) and the resulting 21 month ripened cheese were analysed. Results: Fat and dry matter and fat/casein ratio were lower in MC9 V-milk (p≤0.05) than in MC20. Total bacteria, mesophilic lactic acid and psychrotrophic and lipolytic bacteria showed significant differences (p≤0.05) between the two V-milks. Regarding cheese, fat content resulted lower and crude protein higher (p≤0.05) both in outer (OZ) and in inner zone (IZ) of the MC9 cheese wheels. Concerning total fatty acids, the MC9 OZ had a lower concentration of butyric, capric (p≤0.05) and medium chain fatty acids (p≤0.05), while the MC9 IZ had lower content of butyric (p≤0.05), caproic (p≤0.01) and short chain fatty acids (p≤0.05). The levels of short chain and medium chain free fatty acids (p≤0.05) were lower and that of long chain fatty acids (p≤0.05) was higher in MC9 OZ cheese. The principal component analysis of total and free fatty acids resulted in a clear separation among samples by seasons, whereas slight differences were observed between the two different milk temperatures. Conclusion: Storing milk at 9℃ at the herd affects the chemical composition of Parmigiano Reggiano, with repercussion on lipolysis. However, the changes are not very relevant, and since the cheese can present a high variability among the different cheese factories, such changes should be considered within the "normal variations" of Parmigiano Reggiano chemical characteristics.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1031-1031
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• 2001

The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.