• 한국미생물·생명공학회지
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• 제26권1호
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• pp.55-60
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• 1998

수용성 이상계에서 효율적인 추출발효를 수행하기 위해서는 생체촉매와 생성물이 서로 반대 상에 우세하게 분배되어아 한다. 일반적으로 분자량이 낮은 생성물은 양쪽상에 비슷하게 분배되므로, 상의 조성 등을 조절하여 한쪽상의 체적을 증가시켜 최대한으로 생성물을 추출하여야 한다. 본 연구에서는 PEI와 HEC으로 구성된 수용성 이상계에서 L. helveticus와 젖산의 분배에 미치는 다가 음이온의 농도, pH, 배지의 농도 및 생육배지 농도 등의 영향을 검토하였다. PEI의 상대 이온으로 작용하는 phosphate, sulfate 음이온수의 증가는 PEI 상의 체적을 감소시켜 하부상에 분배되는 세포의 양(Cb)을 감소시켰으며, sulfate 농도의 영향은 phosphate에 비해 적었다. 검토한 범위에서 대략 93%이상의 세포가 HEC-rich상부상에 분배되었다. 이상계에 생육배지 농도를 달리하여 첨가했을 때 배지 중에 존재하는 phosphate와 sulfate 농도에 따라 비슷한 경향을 나타냈지만 낮은 농도로 인하여 그 영향은 크지 않았다. Phosphate 농도에 따른 젖산분배를 검토한 결과 농도가 증가할수록 분배계수는 감소하였으며, 대략 85%가량의 젖산이 PEI의 하부상에 분배되었다. 이 결과로부터 수용성 이상계에서 전하를 띤 저 분자량의 생성물의 추출은 반대 전하를 띠는 폴리머를 하나의 상형성 풀리머로 사용함으로써 증진되었음을 알 수 있었다. 따라서 L. helveticus 세포는 95% 정도가 상부상에 분배되고 젖산은 85%정도가 하부상에 우세하게 분배되므로 PEI/HEC 이상계는 치즈유청으로 부터의 젖산의 추출발효에 가능성이 높은 시스템으로 응용될 수 있는 것으로 생각된다.

• 농업과학연구
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• 제49권3호
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• pp.571-582
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• 2022

Cacao, a major ingredient for making chocolate, has been shown to have potent antioxidant effects. The consumption of raw cacao has beneficial effects on health. This study determined the fermentation properties of yoghurt that was manufactured with cacao nibs (Theobroma cacao L.). The pH of the yogurt containing the cacao nibs was lower than that of the control, and this reduction was both concentration and fermentation time-dependent. Furthermore, the number of lactic acid bacteria in the yogurt made with cacao and its viscosity increased in a cacao nibs dependent manner. In particular, the yoghurt with 5% cacao nibs added had the highest number of lactic acid bacteria at 48 hours at the end point of the fermentation. Whey protein degradation in yogurt containing cacao nibs increased with the fermentation time, and the organic acid production, especially lactic acid, in the yogurt containing cacao nibs increased significantly after 16 hours of fermentation. In addition, the total polyphenol content of the yogurt containing cacao nibs increased, which was proportional to the amount added. Sensory evaluations of the yogurts indicated that overall taste was less desirable as cacao nib loadings increased from 1 to 5% compared with controls. This result is due to the excessive acidity, which was strongly perceived in the absence of added sugar. The development of yogurts with cacao nibs is expected to contribute much to the appeal of fermented milk.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1421-1424
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• 2005

The aim of this study was to evaluate the effect of two diets different in crude fibre content and ingredients on performance and on caecal characteristics of rabbits around weaning. Thirty litters from thirty New Zealand White does were divided at Day 18 in two groups fed, respectively, a low fibre concentrate (LFC, consisting mainly of soybean meal, delactated whey, barley) from Day 18-28 followed by a creep feed (CF, consisting mainly in alfalfa meal, barley and wheat bran) from Day 29-32, and a CF from Day 18-32. After weaning (32 days) both groups were fed the CF ad libitum for two weeks. During the pre-weaning period, mortality, milk intake and solid feed intake (from Day 20) were recorded daily, while the live weight of kits was recorded twice, at 18 and 32 days. At day 28, one rabbit/litter was slaughtered in order to obtain data on caecal content characteristics. After weaning, the rabbits were located in collective cages, feeding ad libitum CF; feed intake, live weight and mortality were recorded weekly for two weeks. During the preweaning period, there were no differences between the groups in milk and solid feed intake and, by consequence, in live weight at weaning; instead, the mortality was higher (12.5 vs 4.5%) for the group (A) that changed diet at 28 days. Group A showed also a higher caecal pH (6.12 vs. 5.72), propionate to butyrate ratio (0.73 vs. 0.46), ammonia content (9.3 vs. 7.1 mmol/l), but a lower total volatile fatty acid content (66.8 vs. 82.1 mmol/l) than B Group, probably due to the dried milk whey in the concentrate. After weaning, there were no significant differences between the two groups. The authors concluded that the use of a low fibre concentrate for suckling rabbits is not recommended.

• 한국식품과학회지
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• 제26권1호
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• pp.74-80
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• 1994

효소에 의한 단백질분해가 유청단백질의 항원성의 저하에 미치는 영향을 조사하기 위한 기본연구로서, 유청단백질의 가수분해특성을 조사하고 competitive inhibition enzyme-linked immunosorbent assay(cELISA)에 의한 항원성의 변화를 검토하였다. 유청단백질의 가수분해는 chymotrypsin, trypsin, pancreatin, 그리고 Aspergillus oryzae유래의 protease를 각기 4시간 동안 행하였다. TNBS(trinitrobenzensulfonic acid)법에 의하여 측정한 유청단백질의 가수분해도(DH)는 chymotrypsin이나 trypsin을 처리한 경우$(5.05{\sim}11.47)$보다 Aspergillus oryzae유래의 protease 및 pancreatin을 처리한 경우$(15.67{\sim}20.20)$가 훨씬 높게 나타났으며, 각 효소의 처리전에 열처리($75^{\circ}C$, 20분)나 pepsin의 처리를 한 경우에 대체로 약간 높게 나타났다. High performance size exclusion chromatography(HPSEC)에 의하여 분자량분포를 조사한 결과, 가수분해물에 따라 10kDa 이상의 polypeptide가 $12{\sim}36%$ 정도 존재하였고, 평균분자량은 $4,252{\sim}9,132$ dalton, 평균길이는 아미노산 $38{\sim}83$개로 나타났다. 또한 쓴맛은 형성되지 않았다. SDS-PAGE의 결과 처리구에 따라 분자량 14.2kDa 이상의 polypeptide가 일부 존재하였으나 native 유청단백질은 대부분 가수분해에 의하여 제거되었음을 확인하였다. 토끼 항WPI항혈청에 의한 cELISA로 검토한 유청단백질 가수분해물의 monovalent 항원성은 효소처리에 의하여 약 $10^{-1.7}{\sim}10^{-4.9}$배 또는 그 이하로 저하되었으며 대체로 가수분해가 많이 일어난 분해물은 그 항원성이 낮아지는 것으로 나타났다. 또한 각 처리구내에서는 열 및 pepsin의 전처리후 다음 효소 분해한 유청단백질 가수분해물(CDP, TDP, PDP, ODP)의 경우 그 항원성이 가장 낮았다. 그중에서도 pancreatin 가수분해물(PDP)의 경우 항원성이 거의 상실된 것으로 나타났다.

• 한국균학회지
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• 제19권1호
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• pp.61-65
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• 1991

액체배양으로 영지버섯과 잎새버섯의 균사체를 생산하고자 cheese 부산물인 유청을 기본배지로 사용하여 배양최적조건 및 배양여액의 생리활성물질에 대하여 조사한 결과는 다음과 같다. 1. 영지버섯은 기본배지인 유청에 CMC 0.5%(w/V), $(NH_4)_2SO_4$(w/v)를 첨가하고 pH 5.5로 조정한 배지에 균질화한 종균을 10%(v/v) 접종하여 9일간 배양하여 10.2g/L의 건조균사를 얻었다. 2. 잎새버섯은 기본배지에 soluble starch 2%(w/v), $KNO_3$0.1%(w/v) 첨가, 초기 pH 5.2 및 종균접종량 8%(v/v)의 최적조건에서 9일간 배양하여 얻어진 건조균사는 6.2g/L 이었다. 3. 균사생육에 대한 식물생장호르몬 첨가의 영향을 보면 영지버섯은 indole-3-acetic를 $10^{-2}$mM 첨가하여 균사생산이 1.2배 증가하였으며, 잎새버섯은 gibberellin A3-3-acetate $10^{-2}$mM 첨가로 균사생산이 1.3배 증가하였다. 4. 영지버섯 균사체배양여액은B. subtilis와 P. aeruginosa에, 잎새버섯 배양여액은 B. subtilis, Staph. aureus, P. aeruginosa 및 T. tonsurans에 대한 항균력을 나타내었다.

• 한국축산식품학회지
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• 제18권2호
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• pp.185-191
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• 1998

Human milk and bovine milk in normal stage were fractionated four parts : whey, skimmilk membrane, and casein pellet. The specific activity (nmole / mim / mg protein) and distribution ratio(%) of suborganella marker enzymes in each separated milk fraction were determined. Especially, neutral $Ca^{2+}$-ATPase, acid $Ca^{2+}$-ATPase, NADH-cytochrome C reductase, and acid phosphatase were higher in human milk. However, both $Ca^{2+}$-ATPases were not detected in all fractions of bovine milk. On the other hand, 5'-nucleotidase, phosphodiesterase I, alkaline phosphatase, and $\gamma$-glutamyl transpeptidase activities in bovine milk were higher than in human milk. Most of the marker enzymes were highly distributed in cream fraction of either human milk or bovine milk, and their specific activities were high to 24 fold from 3 fold when compared with that of whole milk. These results suggest that marker enzymes in mammary epitherial cell are transfered into cream fraction by the membrane rearrangement, and different biochemical reaction between human and bovine exists for milk secretion in mammary gland.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.243-244
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• 2003

The effects of Lactic acid bacteria have been investigated on anti-tumor. cholesterol reduction in blood. promotion of immune and skin-beauty. We are focused on cosmeceutical activity of Lactic acid bacteria (LAB). Ml, which is found in Korean traditional food. Kimchi The LAB.Ml has been identified as Lactobacillus plantarum Ml and individually cultured with Soybean soup and Soybean-Curd whey, until the total acidity has been reached the highest. After then, cell-free extracts from Ml have been used for the following studies. We assessed the effect of Lactobacillus plantarum Ml on the depigmentation of B16FlO melanoma cell. The melanin content of cells was decreased with 1-3% of cultured extracts. The tyrosinase activity was reduced by cell-free extracts of Lactobacillus plantarum Ml. Anti-aging and anti-oxidative activity of Ml cultured extract was also studied in NIH-3T3 human fibroblast cells. It showed that induction of cell proliferation. collagen synthesis and free radical scavenging activity. Additional studies for anti-fungal and anti-acne activity were also detected on Staphylococcus aureus and Propionibacterium acnes, respectively. These results suggest that cultured extract of Lactobacillun plantarum Ml would be used for cosmeceutical ingredients through multifunctional reaction on skin such as whitening, anti-wrinkle. anti-oxidation and anti-acnes.

• Journal of Dairy Science and Biotechnology
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• 제28권1호
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• pp.43-52
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• 2010

In addition to the nutritional values, milk has a wide range of bioactive compounds which have been found to be increasingly important for physiological and biochemical functions on human metabolism and health. Bioactive components in milk comprise specific proteins, peptides, lipids and carbohydrates. Especially, milk proteins are known to exert a wide range of nutritional, functional, and biological activities. And milk proteins are considered the most important source of bioactive peptides, including antihypertensive, antithrombotic, antimicrobial, antioxidative, immunomodulatory, and opioid peptides. Many ingredients containing specific bioactive peptides derived from milk protein hydrolysates have been launched on the market and are currently under development. In future studies more emphasis should be given to the health-promoting effect in the well-defined human clinical studies for the successful development of function foods based on the milk-derived bioactive components.

• Journal of Dairy Science and Biotechnology
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• 제17권1호
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• pp.50-57
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• 1999

Milk is a first food for as long as the mammalian race has existed. A characteristic unique to mammal is their ability to secrete milk as a source of nutrients and immunological protection for their young. From a nutitrional viewpoint, milk has heen described as nature's most perfect food, owing mainly to its biological role as the only source of nutrition for the infant mammal. Milk is estimated to contain more than 100,000 molecular species, However, the average contents of milk can be simplified to 3.4% fat, 3.1% protein (80% casein protein and 20% whey protein), 4.5% lactose, and 0.7% ash. Chemically, milk is a very complex fluid rich in nutrients, antibodies, growth factors, antimicrobial components etc. This report will discuss functional properties of milk components, such as lactoferrin, opoid peptide, CPP, cGMP and sialic acid etc.

• 한국식생활문화학회지
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• 제31권5호
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• pp.489-497
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• 2016

Kunrak, a type of Korea traditional cheese, is made using Tarak, a yogurt produced with makgeolli as the fermentation source. Kunrak is produced by removing whey from Tarak, followed by drying process for safe storage and consumption over a longer period. In this study, we produced kunrak based on the method described in "Imwonsibyukji". Prepared Kunrak was ripening for 96 hours at 20, 30, and $40^{\circ}C$. In order to study characteristics of Kunrak, physiochemical properties (pH, acidity, water contents) and contents of metabolites (organic acids, sugars, amino acids, and fatty acids) were analyzed. During ripening, water contents decreased. The main organic acids in Kunrak were citric acid and lactic acid, and the main free sugar was lactose. Main amino acids were glutamate and phenylalanine, and main fatty acid was saturated capric acid. At later ripening, all metabolites increased immediately after preparation. The sensory evaluation score of overall preference was highest for Kunrak, which was ripening at $40^{\circ}C$ for 96 hours. This study was aimed to assay metabolites of Kunrak under various ripening conditions. The results provide basic data to produce conditions for standardized manufacturing of Kunrak.