• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1153-1160
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• 2009

Lactosucrose ($4^G-\beta$-D-galactosylsucrose) is an oligosaccharide consisting of galactose, glucose, and fructose. In this study, we prepared lactosucrose from lactose and sucrose using a levansucrase derived from Zymomonas mobilis. Optimum conditions for lactosucrose formation were $23^{\circ}C$, pH 7.0, 18.0% (w/v) lactose monohydrate, and 18% (w/v) sucrose as substrates, and 1 unit of enzyme/ml of reaction mixture. Under these conditions, the lactosucrose conversion efficiency was 28.5%. The product was purified and confirmed to be O-$\beta$-D-galactopyranosyl-($1{\rightarrow}4$)-O-$\beta$)-D-glucopyranosyl-($1{\rightarrow}2$)-$\beta$-D-fructofuranoside, or lactosucrose. A mixed-enzyme system containing a levansucrase and a glucose oxidase was applied in order to increase the efficiency of lactose and sucrose conversion to lactosucrose, which rose to 43.2% as a result.

• Food Science of Animal Resources
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• v.39 no.5
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• pp.725-741
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• 2019

In the current study, we first investigated a method for directly transforming lactose into galacto-oligosaccharides (GOS) for manufacturing low-lactose and GOS-enriched skim milk (GSM) and then evaluated its prebiotic potential by inoculating five strains of Bifidobacterium spp. In addition, fermented GSM (FGSM) was prepared using a potentially probiotic Lactobacillus strain and its fermentation characteristics and antioxidant capacities were determined. We found that GOS in GSM were metabolized by all five Bifidobacterium strains after incubation and promoted their growth. The levels of antioxidant activities including radical scavenging activities and 3-hydroxy-3-methylglutaryl-CoA reductase inhibition rate in GSM were significantly increased by fermentation with the probiotic Lactobacillus strain. Moreover, thirty-nine featured peptides in FGSM was detected. In particular, six peptides derived from ${\beta}$-casein, two peptides originated from ${\alpha}s_1$-casein and ${\kappa}$-casein were newly identified, respectively. Our findings indicate that GSM can potentially be used as a prebiotic substrate and FGSM can potentially prevent oxidative stress during the production of synbiotic fermented milk in the food industry.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.121-126
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• 2014

Recently, infant formula products made of caprine milk have gained popularity, mainly because the nutritional composition of caprine milk is similar to that of human milk. In addition, caprine milk is considered to be better than bovine milk in terms of nutrient composition and easier digestion. Compared to bovine milk, caprine milk contains more ${\beta}$-casein, but less ${\alpha}$S1-casein. While the lactose concentration of both bovine and caprine milk is almost the same, a content of total oligosaccharides in caprine milk was approximately five to eight times higher than that in bovine milk. However, as the dairy goat industry in Korea is in a nascent stage of milk production and further processing, many nutritional advantages of caprine milk over bovine milk are not fully conveyed to general consumers. It is recommended that scientific research regarding the nutritional benefits of caprine milk needs to be conducted urgently, owing to the increasing domestic sales of infant formula products made of caprine milk.