• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.433-437
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• 2002

Human milk is normally contaminated with various microorganisms, which seem to produce no ill effects. A contamination of hand-expressed and pump-expressed human milk is a major concern in the collection of storage milk. In this study we compared milks collected by two methods, hand expression and suction breast pump, to quantify differences in the degree of bacterial contamination. Thirty-one samples had been manually expressed. The mean of total bacterial counts was 10,600 CFU/mL (range: 360 ∼59,200 CFU/mL) and coliform counts was 43 CFU/mL (range: 20 ∼ 1,060 CFU/mL) in these samples. Whereas in the 118 breast pump-expressed samples, the mean of total bacterial counts was 20,200 CFU/mL (range: 240 ∼ 492,000 CFU/mL) and coliform counts was 158 CFU/mL (range: 4∼10,600 CFU/mL). There was no bacterial growth when the samples were incubated for 10 days at 4$\^{C}$. We also compared total bacterial growth in colostrum and in matured human milk for 24 hr at 20$\^{C}$ and 30$\^{C}$. Although bacterial growth had not shown for 24 hr at 20$\^{C}$, but shown slight growth in colostrum and rapidly increase in matured human milk for 24 hr at 30$\^{C}$. The coliform bacteria in all samples, particulary in formula milk, had grown at 20$\^{C}$ and 30$\^{C}$.

• 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.

• Journal of Dairy Science and Biotechnology
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• v.35 no.2
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• pp.93-97
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• 2017

Linum usitatissimum L. (flaxseed) is emerging as an important functional food ingredient because of its rich contents, namely, ${\alpha}$-linolenic acid (ALA, omega-3 fatty acid), lignans, and fiber, which are potentially beneficial for human health. Furthermore, flax or flaxseed oil has also been incorporated as a functional food ingredient into various foods such as milk, dairy products, and meat products. Flaxseed is known to possess antimicrobial activity in vitro and in vivo, but its growth-stimulating effect on lactic acid bacteria is not clear. Hence, the objective of this study was to determine whether crude flaxseed extract stimulated the growth kefir-isolated lactic acid bacteria in vitro. The result of this study showed that Lactobacillus kefiranofaciens DN1, Lactobacillus brevis KCTC3102, Lactobacillus bulgaricus KCTC3635, and Lactobacillus plantarum KCTC3105 treated with $100{\mu}L$ of crude flaxseed extract showed significantly higher growth than the control treated with $100{\mu}L$ of water (p<0.05). Based on the results of this study, crude flaxseed extract could be used as a growth stimulator for lactic acid bacteria in various food applications, including production of milk and dairy products.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.831-840
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• 2015

Functionally and physiologically active peptides are produced from several food proteins during gastrointestinal digestion and fermentation of food materials with lactic acid bacteria. Once bioactive peptides (BPs) are liberated, they exhibit a wide variety of physiological functions in the human body such as gastrointestinal, cardiovascular, immune, endocrine, and nervous systems. These functionalities of the peptides in human health and physiology include antihypertensive, antimicrobial, antioxidative, antithrombotic, opioid, anti-appetizing, immunomodulatory and mineral-binding activities.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.209-217
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• 2022

In this study, Enterococcus faecalis BMSE-HMP005 isolated from human breast milk demonstrated antimicrobial effects against multidrug-resistant (MDR) bacterial strains. The bacteriocin produced by E. faecalis BMSE-HMP005 was fractionated using reverse-phase high-performance liquid chromatography. This fraction showed antimicrobial effects against both gram-positive and gram-negative MDR bacteria. No hemolytic reactions were observed. E. faecalis BMSEHMP005 was resistant to vancomycin; however, kanamycin, ampicillin, and erythromycin showed minimum inhibitory concentrations that were lower than the acceptable range provided by the European Food Safety Authority. For artificial gastric juice and bile acid, the survival rates were 98.67% and 95.70%, respectively. These results show the potential utility of E. faecalis BMSE-HMP005 as a probiotic with remarkable antimicrobial effects against MDR bacteria.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.387-392
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• 2010

This studies were carried out to assess fermentation properties of amylase activity and added rice yogurt of Enterococcus faecium KHM-11 isolated from Korean human milk. The amylase activity of Enterococcus faecium KHM-11 was above 23 units. Characterization of carbohydrate fermentation of Enterococcus faecium KHM-11 has D-ribose, D-lactose, L-arabinose and starch. Titratable acidity and viable count of lactic acid bacteria of 4% rice yogurt was higher compared to the 0%. Therefore we were discussed Enterococcus faecium KHM-11 is suitable microorganism for fermented milk added rice powder. Hydrolysates of sugars of fermented milk with 4% rice powder cultured Enterococcus faecium KHM-11 were analyzed by TLC and HPLC. Hydrolysates of lactose and galactose were revealed and hydrolysates of glucose was not revealed in results of TLC and HPLC.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.269-277
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• 2003

This study was carried out to evaluate the safety of Korean human milk. The microorganisms were identified from human milk of 149 healthy mothers by two collection methods, hand and pump expression. The means of total bacterial counts were 2.33x10$^4$ cfu/mL on the samples collected by the pump expression and 7.83xl0$^3$ cfu/mL on those collected by the hand expression. Therefore, the total bacterial counts of pump expression samples was 9.80xl0$^2$∼3.06x10$^4$ cfu/mL more than that of hand expression samples. The coliform counts of pump expression was 9.36xl0$^3$∼8.57xl0$^4$ cfu/mL more than that of hand expression. However, there was any significant differences of the lactic acid bacterial counts between the two samples collected by each methods. 100 strains of 5 patterns of total bacterial counts were isolated based on the morphology of colony in the standard plate count agar. 13 species were identified among the isolated strains. The dominant species in Korean human milk were Staphylococcus which 7 subspecies identified(81% in the rate of total bacteria, 1.07x10$^4$ cfu/mL). Other species identified were Micrococcus, Bacillus, Providencia, Pseudomonas, Yersinia and Acinetobacter. 36 strains of 6 patterns of lactic acid bacterial counts were isolated based on morphology of colony in the BCP agar. 7 species were identified among the isolated strains. The dominant species of lactic acid bacteria in Korean human milk were Lactobacillus brevis(50.9% in the rate of lactic acid bacteria, 4.72xl0$^4$ cfu/mL). Others species identified(49.1% lactic acid bacteria) were Lactobacillus curvatus, Lactobacillus delbrueckii subsp. lactis, Lactobacillus acidophilus, Leuconostic lactis and Streptococcus salivarius subsp. thermophilus.

• Journal of Dairy Science and Biotechnology
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• v.29 no.1
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• pp.55-58
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• 2011

Certain lactic acid bacteria have anti-tumor activity, especially colon cancer. The fermented milk products containing that kind of lactic acid bacteria have to be recommended for human health as excellent health functional foods. This paper have been classified by 5 regions on the functions of lactic acid bacteria related to prevention of colon cancer. 1) Enhancing of host's immune response; Production of cytokines. 2) Binding and degradation of potential carcinogens; Binding and degradation of mutagenicity. 3) The changes of intestinal microflora and production of antitumorigenic or antimutagenic compounds; Production of azoxymethane. 4) Alteration of the metabolic activity of intestinal microflora; Decrease of harmful enzymes in intestinal tract. 5) Alteration of physicochemical conditions in the colon; Decrease of pH and bile acids contents.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.751-755
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• 2006

Dadih is Indonesian traditional fermented buffalo milk believed by the natives to have beneficial effects on human health. This may be due to the probiotic properties possessed by the lactic acid bacteria (LAB) involved in its fermentation process. It was discovered that ten strains of dadih lactic isolates possessed some probiotic properties in vitro. In this study, the adhesion properties of dadih LAB, in comparison with documented probiotic strains, were investigated in vitro by using mucin extracted from human faeces and Caco-2 cells as the models for human intestinal mucosal surface and intestinal cells respectively. The adhesion results showed the distinction of Lactobacillus reuteri IS-27560 in adhering to both mucus layer and Caco-2 cells. The competition assay for adhesion to the mucus layer between dadih LAB and selected pathogens indicated the competence of Lactococcus lactis IS-16183 and Lactobacillus rhamnosus IS-7257 in significantly inhibiting the adhesion of Escherichia coli O157:H7. Accordingly, these two strains may be potential candidates for use as probiotic strains. Overall, the adhesion properties of all dadih LAB strains were relatively comparable to that of Lactobacillus casei Shirota and Lactobacillus rhamnosus GG, the documented probiotic strains.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.48-52
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• 2007

Yogurt base was prepared from skim milk supplemented with 0.2-1.0% (w/v) garlic powder and fermented with lactic acid bacteria (the mixed strain of Lactobacillus acidophilus, Bifidobacterium longum and Streptococcus thermophilus) at 40$^{\circ}C$ for 18 h. Quality characteristics of the prepared yogurt were evaluated for acid production (pH and titratable acidity), number of viable cells, viscosity and sensory properties. The addition of garlic powder inhibited the growth of lactic acid bacteria and decreased the acid production. After 18 h incubation, titratable acidity of garlic yogurt was 1.28-1.08% and was lower than that (1.35%) of yogurt made with only skim milk. However, the viscosity of yogurt was remarkably increased by the addition of garlic powder. The sensory score of yogurt added with 0.2% garlic powder was similar to ordinary yogurt in flavor and overall acceptability. According to sensory score and fermentation characteristics, the optimum concentration of garlic powder was around 0.2%.