• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.343-348
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• 1994

Enterobacter sp. producing -$\beta$-galactosidase with high transgalactosylation activity was isolated from dairy wastewater. The isolate had common biochemical features to E. aerogenes and E. cloacae. Enzyme production increased as the cell mass increased with optimum enzyme activity of 0.21 Unit/mg-protein (o-nitro-phenyl-$\beta$ -D-galactoside (ONPG) as substrate) until 8 hr of culture. Whole cells permeabilized by toluene were used to produce galacto-oligosaccharide. Optimum toluene concentration, temperature and pH for -$\beta$-galactosidase activity of permeabilized whole cells were 10% (v/v), $50^{\circ}C$ and 6.0, respectively. A maximum of 38% (w/w) of galacto-oligosaccharide was obtained with lactose concentration of 20% (w/w) at $40^\{\circ}C$ and pH 6.0.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.514-518
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• 2008

After overproduction of a recombinant $\beta$-galactosidase of Bifidobacterium infantis in Pichia pastoris, a synthesis of galacto-oligosaccharides (GOS) from 36% lactose using the enzyme (170.74 U/mg) was investigated. The transgalactosylation ratio reached up to 25.2% with 83.1% conversion of initial lactose and the maximum yield of GOS was 40.6%. The GOS syrup was composed of a 13.43% galacto-oligosaccharides, 5.06% lactose, and 8.76% monosaccharides. The prebiotic effect of GOS on the growth of bifidobacteria and lactobacilli strains was investigated in vitro. The maximum growth rate of Bifidobacterium breve and Lactobacillus acidophillus in GOS syrup (5%, v/v) media were 0.49 and 0.96/hr that are higher than those in 1%(w/v) galactose and 1%(w/v) lactose containing media. However, there was no significant difference between the specific growth rates of L. acidophillus in 1%(w/v) glucose and 5%(v/v) GOS syrup. Our data showed that GOS definitely promoted the growth of B. breve ATCC $15700^T$ and L. acidophilus ATCC 33323.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.191-202
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• 2017

This study was conducted to investigate the characteristics of major prebiotics and the related studies, and to provide basic data for future research. Prebiotics are defined as 'nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon, and thus improve host health'. Well-known prebiotics are inulin, oligofructose, and galacto-oligosaccharide. Prebiotics assist in the health activity of lactic acid bacteria by acting as a substrate for lactic acid bacteria, with their unique physical and chemical properties. Bifidobacteria are known to be beneficial bacteria that prevent intestinal inflammation, maintain intestinal microflora balance, inhibit carcinogenesis, reduce cholesterol, and enhance immunity. However, Bifidobacteria, Lactobacillus, Bacillus, and Weissella are also found in animal-based fermented foods such as milk, cheese, yogurt, and salted fish. Prebiotics can act as a substrate for lactic acid bacteria, helping the activity of lactic acid bacteria and improving health. Therefore, the authors suggest that investigation into the category and effectiveness of prebiotics should be extended in the future through research.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.1-9
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• 2015

In recent years, the knowledge about bifidobacteria has considerably evolved thanks to recent progress in molecular biology. The analysis of the whole genome sequences of 48 taxa of bifidobacteria offers new perspectives for their classification, especially to set up limit between two species. Indeed, several species are presenting a high homology and should be reclassified. On the other hand, some subspecies are presenting a low homology and should therefore be reclassified into different species. In addition, a better knowledge of the genome of bifidobacteria allows a better understanding of the mechanisms involved in complex carbohydrate metabolism. The genome of some species of bifidobacteria from human but also from animal origin demonstrates high presence in genes involved in the metabolism of complex oligosaccharides. Those species should be further tested to confirm their potential to metabolize complex oligosaccharides in vitro and in vivo.

• 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.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.304-311
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• 2020

Galacto-oligosaccharides (GOS) are prebiotics that have a beneficial effect on human health by promoting the growth of probiotic bacteria in the gut, in addition to having various applications in the food industry. GOS are generally produced from lactose in a reaction catalyzed by β-galactosidase. Synthesis of GOS from whey permeate (WP) (ultrafiltration of whey, concentrated then spray dried) using surface engineered β-galactosidase in Pichia pastoris (P. pastoris) is a novel method to convert waste into a valuable product. Cell-surface display is the expression of peptides and proteins on the surface of living cells by fusing them to functional components of cells. Surface engineered cells have many potential uses. The Flo1p flocculation functional domain, thought to be located near the N terminus, recognizes and adheres non-covalently to cell-wall components such as α-mannan carbohydrates, causing reversible aggregation of cells into flocs.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.565-571
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• 2013

An enzyme ${\beta}$-galactosidase or ${\beta}$-galactohydrolase [EC3.2.1.23], commonly called lactase, mediates galacto-oligosaccharide (GOS) synthesis under conditions of high substrate concentrations. Also, lactase hydrolyzes ${\beta}$($1{\rightarrow}4$) lactose into glucose and galactose, the latter is successively transferred to free lactose to make various oligosaccharides via transgalactosylation. GOS is non-digestible to human digestive enzymes and has been used as a functional prebiotics. Among the 24 lactic acid bacteria (LAB) strains used, Lactobacillus paracasei YSM0308 was selected based on its exhibition of the highest ${\beta}$-galactoside hydrolysis activity, and the crude lactase was prepared for examination of reaction conditions to affect the GOS synthesis. Lactase activity was measured with a spectrophotometer using ONPG (o-nitropheyl ${\beta}$-D-galactopyranoside) method. Lactase activity was not detected in the culture supernatant and was mostly present in the cell pellet after centrifugation. Activity of the crude lactase preparation ranges from102 to 1,053 units/mL, with the highest activity determined for L. paracasei YSM0308. Optimal conditions for GOS synthesis are as follows: concentration of whey powder, pH, temperature, and time were 30%, pH 6.5-7.0, $30^{\circ}C$, and 4 h, respectively. The final GOS concentration was 19.41% (w/v) by the crude YSM0308 lactase, which was obtained from strain YSM0308 grown in the 10% (w/v) reconstituted whey-based medium.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.20 no.2
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• pp.100-106
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• 2017

Purpose: The purpose of this paper is to evaluate the efficacy of a lactose- reduced synbiotic partial whey hydrolysate in formula fed infants presenting with colic and the impact of this dietary intervention in mean crying time and quality of life. Methods: Forty infants with infantile colic were treated during one month with parental reassurance and the intervention formula (partial whey hydrolysate, reduced lactose, Bifidobacterium lactis BB12 and galacto-oligosaccharides) and were compared to a control group of 20 infants with infantile colic treated with parental reassurance and a standard infant formula. Parents completed a quality of life (QoL) questionnaire assessing the burden of infantile colic. Wilcoxon test, t-test and Mann-Whitney test were used to compare QoL scores before and after intervention as well as between the intervention and control group. Results: At inclusion, duration of crying did not differ between both groups. Crying duration decreased with 2.7 hours (from 3.2 to 0.5 hours) in the intervention group while duration of crying decreased only with 1.2 hours in the control group (p<0.001). Stool composition became looser in the intervention group, but defecation frequency did not change. The median scores of the QoL questionnaire improved significantly in the intervention group for all parameters. In the control group, parameters improved significantly also but not for the parent-child and social interaction. The score changes were significantly greater in the intervention than in the control group. Conclusion: The intervention formula (partial whey hydrolysate, synbiotic, reduced lactose) significantly reduced the duration of crying and improved QoL of the parents and infants.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.397-400
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• 2010

The activities of mannanase, ${\beta}$-mannosidase, and ${\alpha}$-galactosidase were detected in culture filtrate of Paenibacillus woosongensis showing mannanolytic activity for locust bean gum. Optimal conditions occurred at pH 5.5 and $60^{\circ}C$ for mannanase toward locust bean gum, pH 6.5 and $50^{\circ}C$ for ${\beta}$-mannosidase toward para-nitrophenyl-${\beta}$-D-mannopyranoside, and pH 6.0-6.5 and $50^{\circ}C$ for ${\alpha}$-galactosidase toward para-nitrophenyl-${\alpha}$-D-galactopyranoside in the culture filtrate, respectively. The mannanolytic enzyme of culture filtrate hydrolyzed mannobiose as well as manno-oligosaccharides including mannotriose, mannotetraose, mannopentaose and mannohexaose. It could also hydrolyze ${\alpha}$-1,6 linked galacto-oligosaccharides such as melibiose, raffinose and stachyose to liberate galactose residue. From these results, it is assumed that P. woosongensis produces three enzymes required for the complete decomposition of galactomannan.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.723-731
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• 2008

Immunomodulatory feed additives might offer alternatives to antimicrobial growth promoters in pig production. This experiment was designed to determine the effects of dietary galacto-mannan-oligosaccharide (GMOS) and chitosan oligosaccharide (COS) supplementation on the immune response in early-weaned piglets. Forty 15-day-old piglets (Duroc$\times$Landrace$\times$Yorkshire) with an average live body weight of $5.6{\pm}0.51kg$ were weaned and randomly assigned to 4 treatment groups that were fed maize-soybean meal diets containing either basal, 110 mg/kg of lincomycin, 250 mg/kg of COS or 0.2% GMOS, respectively, over a 2-week period. Another six piglets of the same age were sacrificed on the same day at the beginning of the study for sampling, in order to obtain baseline values. Interleukin (IL)-1${\beta}$gene expression in peripheral blood monocytes, jejunal mucosa and lymph nodes, as well as serum levels of IL-1${\beta}$ IL-2 and IL-6, IgA, IgG, and IgM, were evaluated for 5 pigs from each group at 15 and 28 days of age. The results indicate that weaning stress resulted in decreases in serum antibody and cytokine levels. Dietary supplementation with GMOS or COS enhanced (p<0.05) IL-1${\beta}$gene expression in jejunal mucosa and lymph nodes, as well as serum levels of IL-1${\beta}$ IL-2, IL-6, IgA, IgG and IgM compared to supplementation with lincomycin. These findings suggest that GMOS or COS may enhance the cell-mediated immune response in early-weaned piglets by modulating the production of cytokines and antibodies, which shows that GMOS or COS have different effects than the antibiotic on animal growth and health.