• Journal of Microbiology and Biotechnology
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• v.29 no.11
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• pp.1717-1728
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• 2019

The gene encoding β-galactosidase was cloned from Bifidobacterium longum RD47 with combinations of several bifidobacterial promoters, and expressed in B. bifidum BGN4. Among the recombinant bifidobacteria, BGN4+G1 showed the highest β-galactosidase level, for which the hydrolytic activity was continuously 2.5 to 4.2 times higher than that of BGN4 and 4.3 to 9.6 times higher than that of RD47. The β-galactosidase activity of BGN4+G1 was exceedingly superior to that of any of the other 35 lactic acid bacteria. When commercial whole milk and BGN4+G1 were reacted, BGN4+G1 removed nearly 50% of the lactose in the milk by the 63-h time point, and a final 61% at 93 h. These figures are about twice the lactose removal rate of conventional fermented milk. As for the reaction of commercial whole milk and crude enzyme extract from BGN4+G1, the β-galactosidase of BGN4+G1 eliminated 51% of the lactose in milk in 2 h. As shown below, we also compared the strengths and characteristics of the strong bifidobacterial promoters reported by previous studies.

• Korean Journal of Community Nutrition
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• v.8 no.4
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• pp.584-594
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• 2003

The lactose, total nitrogen and total lipid contents of human breast milk were determined longitudinally after protein and term deliveries. Milk samples were obtained from day 2 to 5, on weeks 1, 2, 4, and 6 after preform (PM : n = 24) and term (TM : n = 22) deliveries. The lactose contents of PM and TM increased from 5.28 g/dl and 5.93 g/dl at days 2 to 5, to 7.95 g/dl,7.87 g/dl at 6 weeks, respectively. The total nitrogen contents of PM and TM decreased significantly during the first 6 weeks after birth (from 374 to 220 mg/dl versus 382 to 220 mg/dl respectively). However the total lipid contents of the PM and TM increased during the same periods. Significant differences in the total lipid contents between the PM and TM were 2.15 versus 3.27 g/dl at 2 weeks, and 3.26 versus 2.52 g/dl at 6 weeks, respectively. The energy intakes of preform infants was 134.8 ㎉/kg/d during the 6 weeks of lactation, which satisfied with energy requirements (85-130 ㎉/kg/d) of the preform infants. (Korean J Community Nutrition 8(4) : 584-594, 2003)

• Development and Reproduction
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• v.17 no.1
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• pp.1-8
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• 2013

Osteoprotegerin (OPG) is a secreted glycoprotein that regulates bone resorption by inhibiting differentiation and activation of osteoclast, thereby potentially useful for the treatment of many bone diseases associated with increased bone loss. In this study, we designed a novel cDNA expression cassette by modifying the potent and mammary gland-specific goat ${\beta}$-casein/hGH hybrid gene construct and examined human OPG (hOPG) cDNA expression in transgenic mice. Six transgenic mice all successfully expressed hOPG in their milk at the level of 0.06-2,000 ${\mu}g/ml$. An estimated molecular weight of the milk hOPG was 55 kDa in SDS-PAGE, which is the same as a naturally glycosylated monomer. This hOPG expression was highly specific to the mammary glands of transgenic mice. hOPG mRNA was not detected in any organs analyzed except mammary gland. Functional integrity of milk hOPG was evaluated by TRAP (tartrate-resistant acid phosphatase) activity assay in bone marrow cell cultures. OPG ligand (OPG-L) treatment increased TRAP activity by two fold but it was completely abolished by co-treatment with transgenic milk containing hOPG. Taken together, our novel cDNA expression cassette could direct an efficient expression of biologically active hOPG, a potential candidate pharmaceutical for bone diseases, only in the mammary gland of transgenic mice.

• Korean Journal of Community Nutrition
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• v.12 no.3
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• pp.223-234
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• 2007

This study was done to determine the trans fatty acid (tFA) composition of human milk from postpartum to sixth months after delivery, to investigate the tFA intake of lactating women, and to estimate the intakes of tFA by infants exclusively fed breast milk. A total of 27 lactating Korean women participated to this study voluntarily, gave their breast milk, and responded to an investigation of their diets. The lactating women consumed 2.3-2.8 g/d of tFAs over the period of the first, second, third, and sixth months postpartum, which was 3.4-4.9% of the total fat intake and 0.8%-1.2% of the total energy intake. The proportions of tFAs in the breast milk were 1.89% in colostrum, 1.78% in transitional milk, and 1.78-2.25 in mature milk of the first, second, third, and sixth months postpartum. The tFAs of the breast milk identified in this study were C16:1n9t, C18:1n9t, C18:2n6t12t, C18:2n6t12c, C18:2n6t12t and C18:2n6t11t. Among them, C18:1n9t was predominant, which made up 59.26% of all tFAs in cob strum, 62.36% in transitional milk, and 64.42% in mature milk. The proportion of total tFA was unchanged with time, although some significant differences were noted for individual tFAs. The percentages of C18:2n6t12c and C18:2n6c12t decreased over the study period. Estimated tFA intake of the exclusively breast-fed infants was 0.18 g/d when fed colostrum, 0.29 g/d when fed transitional milk, and 0.53 g/d when fed mature milk until the sixth month of postpartum. Those were 0.5%, 0.8%, and 1.1% of the total energy intake. The results in this study indicate that lactating Korean women consume not a large quantity of tFAs, secrete breast milk not containing much tFA, and the estimated intake of tFAs by infants fed exclusively breast milk is not great.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.296-300
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• 2006

Immunoblotting and competitive indirect enzyme-liked immunosorbent assay(Ci-ELISA) was used for detection of ${\beta}$-lactoglobulin(BLG) in dairy products, such as milk, dried milk and fermented milk. In immunoblotting, human IgE weakly recognized proteins of fermented milk, but still responded to dried milk even though become weak. Rabbit polyclonal antibody to BLG, used as a model of antigen, and milk allergic patients' IgE was used in the ELISA. Reactivities of Abs were the highest in market milk. BLG in fermented milk was detected in a low content. This result indicates the fermented milk have the lowest BLG content and could be used as hypo-allergenic food for milk-allergic individual.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.82.1-82.1
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• 2007

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• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.386-391
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• 2012

The principal objective of this study was to evaluate the quality characteristics of black garlic milk tofu prepared with five different levels (0%, 0.5%, 1%, 1.5%, and 2.0%) of black garlic concentrate (BG0~BG4). We conducted the pH, total phenol and flavonoids, Hunter's color values, mechanical characteristics, and a sensory evaluation analysis of black garlic milk tofu. The total phenol and flavonoid content of black garlic concentrate were 1.67mg/100 g and 1.07 mg/100 g. The more black garlic concentrate increased, the more lightness (L) decreased, but redness(a) and yellowness (b) increased. The hardness, gumminess, and chewiness scores significantly increased (p<0.05) in all black garlic milk tofu samples. In color, taste, flavor, texture, and overall quality, the score of milk tofu with 1.0% black garlic concentrate (BG2) increased the most.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.513-522
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• 2017

This study was conducted to examine the relationships between milk and milk product intake and bone health. The data from the 2008~2011 Korean National Health and Nutrition Examination Survey (KNHANES) were used for data analysis. Subjects included 4,626 men and 6,144 women aged 19 to 64 years. Daily intake frequency of milk and milk products was obtained using a food frequency questionnaire and divided into two categories: less than one serving per day and more than one serving per day. Bone mineral density (BMD) values of total femur, femoral neck, and lumbar spine were compared based on daily intake frequency, and relationships between milk and milk product daily intake frequency and osteoporosis risk were evaluated based on logistic regression. In men aged 30~39, BMDs of total femur and femoral neck were significantly higher in the group that consumed milk more than one serving per day (P<0.05). Intake frequency of milk and milk products was also significantly related to both BMDs of total femur and femoral neck. The odds ratio (OR) for milk intake frequency (more than one serving per day) compared to intake frequency less than one serving per day was 0.36 [95% confidence interval (CI) 0.21~0.62], and the OR for milk and milk products intake frequency (more than one serving per day) was 0.49 (95% CI 0.28~0.86) in women aged 50~64. These results indicate that increased consumption of milk and its products is associated with reduced risk of bone health disease, and adequate intakes of milk and milk products might play an important role in maintaining optimum bone health. Further research on the causal relationship and dose-response association between milk intake and bone heath using prospective cohort data is required prior to applying the observed results to programs that prevent bone health problems.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.442-449
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• 1991

Concentrations of iron. zinc, and copper were measured in human milk samples collected longitudinally from 21 highly selected. healthy lactating women. And the daily milk and trace elements intakes of 14 exclusively breastfed infants were determined by the test-wei-ghing procedure and the direct analysis of milk samples at 6 or 7weeks postpartum. Significant decreases in iron. zinc and copper were found with time postpartum. Iron contents decreased from 0.33$\mu\textrm{g}$/$m\ell$ at 2-5 days to o.21$\mu\textrm{g}$/$m\ell$ at 12weeks. Zinc concentrations also declined from 4.15$\mu\textrm{g}$/$m\ell$ in colostrum to 2.33$\mu\textrm{g}$/$m\ell$ in matured milk at 12 weeks. Mean copper levels of colostum, transitional. and matured milk were 0.21$\mu\textrm{g}$/$m\ell$, 0.34$\mu\textrm{g}$/$m\ell$, and 0.26$\mu\textrm{g}$/$m\ell$ respectively. Data indicated that the amount of milk ingested ranged from 432g/day to 1266g/day and the mean intake was 768g/day. Daily mean intakes for iron, zinc, and copper were 0.19mg, 2.10mg, and 0.15mq respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.301-301
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• 2022

Dairy products are important diet source for human because of their balanced essential nutrients along with various vitamins and minerals. However, lactose in milk can result in diarrhea to some consumers with lactose intolerance. Soy milk has no lactose and is suitable as a substitute for diary milk in accordance with recent trend of replacing animal food with vegetable food. However, polysaccharides in soy milks are difficult for humans to digest, leading to flatulence. These polysaccharides can be decomposed into monosaccharides by lactic acid bacteria, and fermentation can improve food quality. Because mungbean has higher carbohydrate content than soybean, mung milk can be easily fermented than soy milk, resulting in vege yogurt with higher contents of lactic acid. In this study, fermentation characteristics of vege yogurt were analyzed with different ratio of soy milk and mung milk (0%, 25%, 50%, 75%, 100% and 0%+sucrose) and different fermentation time (0, 8, and 16 hours). In general, pH decreased as fermentation time increased. Overall, pH significantly decreased when the mung milk content in yogurt increased. All samples showed higher titratable acidity after fermentation and soy yogurt (mungbean 0%, 16 hours) with sucrose showed the highest value (6.825%). As fermentation time increase, viscosity increased. In 8 and 16 hours, mung milk yogurt (mungbean 100%) showed the lowest viscosity while soy milk yogurt (soybean 100%) with no sucrose showed the highest viscosity after 16 hours of fermentation. The contents of crude protein, crude fat and ash were measured for nutritional analysis. Soy milk (mungbean 0%, 0 hours) had the values of crude protein 2.9g, crude fat 1.8g, and ash 0.3g, and mung milk (mungbean 100%, 0 hours), showed the values of crude protein 1.7g, crude fat 0g, and ash 0.3g. To analyze the effect of the differences in the contents of nutrition between soy milk and mung milk on fermentation, the changes in sugar contents, and antioxidant capacity will be conducted depending on fermentation time. Our results will provide the information in researching plant beverages.