• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1196-1206
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• 2014

A metagenomic fosmid library was constructed using genomic DNA isolated from the gut microflora of Hermetia illucens, a black soldier fly. A cellulase-positive clone, with the CS10 gene, was identified by extensive Congo-red overlay screenings for cellulase activity from the fosmid library of 92,000 clones. The CS10 gene was composed of a 996 bp DNA sequence encoding the mature protein of 331 amino acids. The deduced amino acids of CS10 showed 72% sequence identity with the glycosyl hydrolase family 5 gene of Dysgonomonas mossii, displaying no significant sequence homology to already known cellulases. The purified CS10 protein presented a single band of cellulase activity with a molecular mass of approximately 40 kDa on the SDS-PAGE gel and zymogram. The purified CS10 protein exhibited optimal activity at $50^{\circ}C$ and pH 7.0, and the thermostability and pH stability of CS10 were preserved at the ranges of $20{\sim}50^{\circ}C$ and pH 4.0~10.0. CS10 exhibited little loss of cellulase activity against various chemical reagents such as 10% polar organic solvents, 1% non-ionic detergents, and 0.5 M denaturing agents. Moreover, the substrate specificity and the product patterns by thin-layer chromatography suggested that CS10 is an endo-${\beta}$-1,4-glucanase. From these biochemical properties of CS10, it is expected that the enzyme has the potential for application in industrial processes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.27-31
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• 2001

To investigate the food organisms and feeding selectivity of the white croaker (Argrosomus argentatus) during the postlarval stage, the gut contents of the postlarvae, captured in Kwangyang Bay in 1995, were observed, The food organisms were composed of copepod egg and nauplius, Codonellopsis sp. and Tintinnopsis spp. The indices of relative importance indicated that the most dominant food item was a copepod nauplius. As white croaker larvae grew, the size of prey items and the selectivity for copepod nauplius increased.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.1
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• pp.22-27
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• 2013

The prevalence of obesity is increasing worldwide. Obesity can cause hyperlipidemia, hypertension, cardiovascular diseases, metabolic syndrome and non-alcoholic fatty liver disease (NAFLD). Many environmental or genetic factors have been suggested to contribute to the development of obesity, but there is no satisfactory explanation for its increased prevalence. This review discusses the latest updates on the role of the gut microbiota in obesity and NAFLD.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.1-8
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• 2021

Human breast milk is a potential source of bacteria for the development of the intestinal microbiota of infants. Several species within the genera Lactobacillus and Bifidobacterium were demonstrated to shape the gut microbiota of infants. In this study, the bacterial diversity was investigated in the breast milk and feces of a mother-infant pair, and probiotic candidates were identified. Importantly, the novel L. gasseri EJL and B. breve JTL strains were isolated from breast milk and infant feces samples, respectively; their completed genome was resolved using de novo sequencing. In addition, the bacterial composition in the infant's feces at 1 week revealed the prevalence of Bifidobacterium and Streptococcus; a higher diversity was observed after 3 weeks. In particular, the abundance of Akkermansia was sharply increased at 7 weeks, further increasing thereafter, up to 15 weeks. Our results suggest that human breast milk and infant's feces are a source of probiotic candidates.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1313-1319
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• 2013

This study investigated the effects of low levels of water-soluble pentosans (WSP), alkaline-extractable pentosans (AEP), and xylanase on the growth and organ development of broiler chicks. Three hundred and fifty 1-d-old female broiler chicks were randomly allocated into seven experimental groups of five pen replicates, with ten chicks per replicate. The control group consumed a corn-soybean meal-based diet. Six dietary treatment groups consumed the basal diet supplemented with one of the following: WSP at 50 mg/kg (WSP50) or 100 mg/kg (WSP100); AEP at 50 mg/kg (AEP50) or 100 mg/kg (AEP100); or xylanase at 3 mg/kg (Xase3) or 6 mg/kg (Xase6). Data including the body weight, digestive organ weights, gut length, rectal digesta viscosity, and gut microflora and pH were collected on d 5, 10, and 15. When compared to the control group, WSP50 promoted body weight gain and organ growth throughout the study, calculated as 3-d averages (p<0.05). WSP100 increased weight gain and enhanced organ development (proventriculus, gizzard, and gut) on d 10 (p<0.05), but the 3-d averages were not different from the control group except for the weight of gizzard. Both Xase3 and Xase6 increased the 3-d average weight gain and the growth of the gizzard (p<0.05). WSP50 increased the digesta viscosity compared to Xase3 on d 10 and 15 (p<0.05). WSP50, Xase3, and Xase6 increased the concentration of Lactobacillus in the rectum when compared to the control group (p<0.05), but only Xase3 lowered the digesta pH in the ileum and cecum on d 10 and 15. AEP had minimal influence on the growth and organ development of broilers. The results showed that low levels of WSP, AEP, and xylanase had different effects and underlying mechanisms on the growth and organ development of broiler chicks. WSP50 could increase the growth performance of broilers fed a corn-soybean meal-based diet.

• IMMUNE NETWORK
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• v.22 no.2
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• pp.17.1-17.14
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• 2022

We aimed to investigate associations of dietary diversity (DD) with gut microbial diversity and the development of hen's egg allergy (HEA) in infants. We enrolled 68 infants in a high-risk group and 32 infants in a control group based on a family history of allergic diseases. All infants were followed from birth until 12 months of age. We collected infant feeding data, and DD was defined using 3 measures: the World Health Organization definition of minimum DD, food group diversity, and food allergen diversity. Gut microbiome profiles and expression of cytokines were evaluated by bacterial 16S rRNA sequencing and real-time reverse transcriptase-polymerase chain reaction. High DD scores at 3 and 4 months were associated with a lower risk of developing HEA in the high-risk group, but not in the control group. In the high-risk group, high DD scores at 3, 4, and 5 months of age were associated with an increase in Chao1 index at 6 months. We found that the gene expression of IL-4, IL-5, IL-6, and IL-8 were higher among infants who had lower DD scores compared to those who had higher DD scores in high-risk infants. Additionally, high-risk infants with a higher FAD score at 5 months of age showed a reduced gene expression of IL-13. Increasing DD within 6 months of life may increase gut microbial diversity, and thus reduce the development of HEA in infants with a family history of allergic diseases.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.670-677
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• 2011

The growth rate of the young pig is generally much less than it's potential and may be constrained by endocrine status as well as nutrient intake. Growth factors are present in relatively high quantities in colostrum and play an important part in gut development. It is possible that supplementation of colostrum protein isolate may stimulate gut and whole body growth in the pig. Eight male and 8 female (Large Whitex${\times}$Landrace) piglets were weaned at 1 d of age after each pig had obtained colostrum from their dam, and were trained to consume one of two liquid diets. The two diets were based on either a colostrum protein isolate (n = 4 males and 4 females) or whey protein concentrate (n = 4 males and 4 females) and were formulated to contain equal levels of crude protein and amino acids. Pigs were fed their diets ad libitum for 28 days after which time 12 pigs were euthanised and various tissues and organs weighed. Pigs were bled for IGF-I analyses at 21 and 28 days of age. Daily gain was higher in pigs consuming the colostrum isolate (171 vs. 216 g/d, p = 0.010), particularly between 2 and 4 weeks of age (212 vs. 298 g/d, p = 0.010). Pigs tended to consume more of the liquid feed containing colostrum isolate (25.5 vs. 29.1 kg, p = 0.074) and gained more live weight per unit of liquid feed (0.203 vs. 0.223 g/g, p = 0.056). There were no effects of sex on growth performance. Pigs consuming the diet supplemented with colostrum isolate had higher (p<0.05) full gut weight (445 vs. 554 g, p = 0.026), empty gut weight (356 vs. 463 g, p = 0.008), stomach weight (42.2 vs. 54.4 g, p = 0.001), small intestine weight (222 vs. 275 g, p = 0.025) and large intestine weight (63.7 vs. 98.0 g, p = 0.005). Plasma IGF-I (99 vs. 150 ng/ml, p<0.001) and IGF-II (265 vs. 406 ng/ml, p<0.001) were higher in pigs fed colostrum isolate. Pigs consuming colostrum protein isolate ate more, grew faster and had higher plasma IGF-I concentrations than pigs consuming a diet with similar macronutrient content but devoid of growth factors.

• Economic and Environmental Geology
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• v.48 no.3
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• pp.255-260
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• 2015

There are more than 2000 minerals on earth, and it has been implemented in various fields such as environment, architecture, livestock, chemistry, pharmaceuticals. Clay minerals are considered that they can change the physical and chemical properties through the adsorption and release of metal ions. Although domestic deposit of non-metallic mineral resources is approximately ninety-six billion tons, its application is limited and has hardly been used in high value-added industries involved in medicine, medical supplies, and functional food materials. Bentonite and zeolite are already used for cosmetic purposes and also used in living goods and packing materials. However, direct application to the food industry is relatively very rare. Since records regarding the intake of minerals for foods and medicines are found in the old literatures, the utilization of non-metallic minerals as food materials appears to be highly profitable. According to the trends in patent research for food and mineral resources, the company plays a main role for the development of the food containing non-metallic minerals in USA, and the trends confirms that this industry is emerging. Here, we provided the information about domestic and foreign patent trend for food industries involved in mineral resources and the application of mineral resources in the food industries. We also covered the domestic regulation regarding usage of mineral resources in food, and proposed domestic application plan for food production using mineral resources in the future.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.165-172
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• 2018

Due to the recent economic development, the diet style has become more and more westernized in Korea, which increased the concern of our well-beings. Our well-beings are also associated with the gut microbiota which vary depending on the dietary intake. In this study, we compared gut microbiome shifted by two diets: high-fat diets (HFD) and low-fiber diet (LFD) based on 16S rRNA gene sequences using MiSeq. Compared to the control diet, LFD and HFD treatments significantly decreased species richness, while there was no difference in species evenness. Both diet treatments significantly increased the relative abundance of the Proteobacteria (p<0.05), especially the genus Sutterella. Bacteroidetes was significantly decreased in HFD groups, where the family S24-7 was decreased most. On the other hand, significant difference between HFD and LFD was seen among Firmicutes, where the abundance of family Lachnospiraceae was lower in LFD groups (p<0.05). PICRUSt-based metabolic difference analyses showed LFD treatment significantly decreased metabolisms of amino acid, carbohydrate and methane (p<0.01). In contrast, HFD significantly increased amino acid metabolism (p<0.05). Glycan biosynthesis and metabolism were significantly increased in both treatment groups (p<0.01). Our results suggest that long-term unbalanced dietary intakes induce gut dysbiosis, leading to metabolic and colonic disorders.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1883-1895
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• 2018

Alcohol dependence is a global public health problem, yet the mechanisms of alcohol dependence are incompletely understood. The traditional view has been that ethanol alters various neurotransmitters and their receptors in the brain and causes the addiction. However, an increasing amount of experimental evidence suggests that gut microbiota also influence brain functions via gut-to-brain interactions, and may therefore induce the development of alcohol use disorders. In this study, a rat model of alcohol dependence and withdrawal was employed, the gut microbiota composition was analyzed by high-throughput 16S rRNA gene sequencing, and the metagenome function was predicted by PICRUSt software. The results suggested that chronic alcohol consumption did not significantly alter the diversity and richness of gut microbiota in the jejunum and colon, but rather markedly changed the microbiota composition structure in the colon. The phyla Bacteroidetes and eight genera including Bacteroidales S24-7, Ruminococcaceae, Parabacteroides, Butyricimonas, et al were drastically increased, however the genus Lactobacillus and gauvreauii in the colon were significantly decreased in the alcohol dependence group compared with the withdrawal and control groups. The microbial functional prediction analysis revealed that the proportions of amino acid metabolism, polyketide sugar unit biosynthesis and peroxisome were significantly increased in the AD group. This study demonstrated that chronic alcohol consumption has a dramatic effect on the microbiota composition structure in the colon but few effects on the jejunum. Inducement of colonic microbiota dysbiosis due to alcohol abuse seems to be a factor of alcohol dependence, which suggests that modulating colonic microbiota composition might be a potentially new target for treating alcohol addiction.