• Biomolecules & Therapeutics
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• v.29 no.4
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• pp.353-364
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• 2021

The gastrointestinal (GI) tract is a series of hollow organs that is responsible for the digestion and absorption of ingested foods and the excretion of waste. Any changes in the GI tract can lead to GI disorders. GI disorders are highly prevalent in the population and account for substantial morbidity, mortality, and healthcare utilization. GI disorders can be functional, or organic with structural changes. Functional GI disorders include functional dyspepsia and irritable bowel syndrome. Organic GI disorders include inflammation of the GI tract due to chronic infection, drugs, trauma, and other causes. Recent studies have highlighted a new explanatory mechanism for GI disorders. It has been suggested that autophagy, an intracellular homeostatic mechanism, also plays an important role in the pathogenesis of GI disorders. Autophagy has three primary forms: macroautophagy, microautophagy, and chaperone-mediated autophagy. It may affect intestinal homeostasis, host defense against intestinal pathogens, regulation of the gut microbiota, and innate and adaptive immunity. Drugs targeting autophagy could, therefore, have therapeutic potential for treating GI disorders. In this review, we provide an overview of current understanding regarding the evidence for autophagy in GI diseases and updates on potential treatments, including drugs and complementary and alternative medicines.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.32-56
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• 2023

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

• Genomics & Informatics
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• v.21 no.1
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• pp.5.1-5.13
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• 2023

Neisseria gonorrhoeae is a Gram-negative aerobic diplococcus bacterium that primarily causes sexually transmitted infections through direct human sexual contact. It is a major public health threat due to its impact on reproductive health, the widespread presence of antimicrobial resistance, and the lack of a vaccine. In this study, we used a bioinformatics approach and performed subtractive genomic methods to identify potential drug targets against the core proteome of N. gonorrhoeae (12 strains). In total, 12,300 protein sequences were retrieved, and paralogous proteins were removed using CD-HIT. The remaining sequences were analyzed for non-homology against the human proteome and gut microbiota, and screened for broad-spectrum analysis, druggability, and anti-target analysis. The proteins were also characterized for unique interactions between the host and pathogen through metabolic pathway analysis. Based on the subtractive genomic approach and subcellular localization, we identified one cytoplasmic protein, 2Fe-2S iron-sulfur cluster binding domain-containing protein (NGFG RS03485), as a potential drug target. This protein could be further exploited for drug development to create new medications and therapeutic agents for the treatment of N. gonorrhoeae infections.

• Journal of Ginseng Research
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• v.47 no.6
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• pp.694-705
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• 2023

Panax ginseng Meyer is a traditional Chinese medicine that is widely used as tonic in Asia. The main pharmacologically active components of ginseng are the dammarane-type ginsenosides, which have been shown to have anti-cancer, anti-inflammatory, immunoregulatory, neuroprotective, and metabolic regulatory activities. Moreover, some of ginsenosides (eg, Rh2 and Rg3) have been developed into nutraceuticals. However, the utilization of ginsenosides in clinic is restrictive due to poor permeability in cells and low bioavailability in human body. Obviously, the dammarane skeleton and glycosyls of ginsenosides are responsible for these limitations. Therefore, improving the oral bioavailability of ginsenosides has become a pressing issue. Here, based on the structures of ginsenosides, we summarized the understanding of the factors affecting the oral bioavailability of ginsenosides, introduced the methods to enhance the oral bioavailability and proposed the future perspectives on improving the oral bioavailability of ginsenosides.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.563-569
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• 2013

This study was carried out to investigate the dose-response of chitooligosaccharide (with a molecular weight of 1~3 kDa) on antimicrobial activity and lipid lowering functions in rats. Sprague-Dawley male rats were given experimental diets containing 0 (control), 0.5, 2, or 5% chitooligosaccharide (COS) for 5 weeks. Weight gain and food intake were significantly lower in rats fed 5% COS than control rats and rats fed 0.5 and 2% COS. The numbers of fecal bacteria, including bifidobacteria, lactobacilli, bacteroides, total anaerobes, and total aerobes, which reflect gut microbiota, were significantly decreased in rats fed 5% COS. Plasma triglyceride concentrations significantly decreased in a dose-dependent manner in rats fed 2% or 5% COS, while plasma total cholesterol was not significantly different among groups. The hepatic concentration of triglycerides was lower in rats fed 5% COS, and fecal triglycerides significantly increased in rats fed 5% COS. These results indicate that 5% COS supplementation in a diet may exert antimicrobial activity in vivo, and inhibit the proliferation of typical gut microbes, while lowering lipids.

• Journal of Life Science
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• v.23 no.10
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• pp.1295-1303
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• 2013

According to facts revealed up until the present, there are a total of 68 known phyla on earth, including 55 phyla of bacteria and 13 phyla of archaea. The human large intestine has 9 phyla of microorganisms, which is a relatively lower diversity compared to the general environments of soil or sea. The diversity of intestinal microorganisms is affected by the characteristics of the host (genetic background, sex, age, immune system, and gut motility), the diet (non-digestible carbohydrates, fat, prebiotics, probiotics), and the intake of antibiotics, which in turn have an effect on energy storage processes, gene expressions, and even metabolic diseases like obesity. Probiotics are referred to as living microorganisms that improve the intestinal microbiota and contribute to the health of the host; in addition, probiotics usually comprise lactic acid bacteria. Recently, bacteriotherapy using probiotics has been utilized to treat sicknesses like diarrhea and irritable bowel syndrome. Prebiotics are a food ingredient which can selectively adjust intestinal microorganisms and which comprise inulin, fructooligosaccharides, galactooligosaccharides, and lactulose. In recent days, attention has been paid to the use of dietary cellulose in the large intestine and the production of short chain fatty acids (short-chain fatty acids) in relation to obesity and anticancer. More research into microorganisms in the large intestine is necessary to identify specific microorganism species, which are adjusted by diverse non-digestible carbohydrates, prebiotics, and probiotics in the large intestine and to understand the connection between sicknesses and metabolites like short chain fatty acids produced by these microorganism species.

• Journal of Life Science
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• v.27 no.12
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• pp.1421-1429
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• 2017

The present study was undertaken to investigate the effects of dietary provision of lactic acid bacteria (LB) and sea tangle (ST) on the obesity-associated intestinal microbiota in rats with obesity induced by a high-fat diet. Forty-eight 8-wk-old Sprague-Dawley rats were fed a basal diet (CON), a high fat diet (HFD; CON supplemented with 10% lard), HF supplemented with LB [HFL; $5{\times}10^8cfu$ of each of Lactobacillus rhamnosus, Lactobacillus johnsonii, Bifidobacterium longum and Bifidobacterium lactis], or HFL containing 10% ST (HFLS), with 4 replicates (cages) of 3 rats per dietary treatment, for 6 wk, and the intestinal microbiota were determined by pyrosequencing. The HFL and HFLS groups exhibited reduced rates of weight gain than the HF group, and the former groups had smaller ratios of Firmicutes and greater ratios of Bacteriodetes, with decreased Firmicutes/Bacteroidetes ratios, than the latter at the level of the phylum. Compared with the results for the HF group, HFL and HFLS had reduced ratios of the families of Roseburia, Mollicute, Erysipelotrichi, and Oscillibacter within Firmicutes associated with obesity and increased ratios of the families of Prevotella, Alistipes and Bacteroides within the Bacterioidetes phylum known to have an anti-obesity effect. The content of butyric acid in feces was greater in the HFLS group vs. HF and HFL. In conclusion, the present results suggest that dietary provision of LB plus ST has an anti-obesity effect and induced changes in intestinal microorganisms, and enhanced the content of butyric acid, which is an intestinal metabolite.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.1
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• pp.64-70
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• 2017

Objective: In the present study, role of increasing levels of Ecklonia cava (seaweed) supplementation in diets was investigated on growth performance, coefficient of total tract apparent digestibility (CTTAD) of nutrients, serum immunoglobulins, cecal microflora and intestinal morphology of weanling pigs. Methods: A total of 200 weaned pigs (Landrace${\times}$Yorkshire${\times}$Duroc; initial body weight $7.08{\pm}0.15kg$) were randomly allotted to 4 treatments on the basis of body weight. There were 5 replicate pens in each treatment including 10 pigs of each. Treatments were divided by dietary Ecklonia cava supplementation levels (0%, 0.05%, 0.1%, or 0.15%) in growing-finishing diets. There were 2 diet formulation phases throughout the experiment. The pigs were offered the diets ad libitum for the entire period of experiment in meal form. Results: The pigs fed with increasing dietary concentrations of Ecklonia cava had linear increase (p<0.05) in the overall average daily gain, however, there were no significant differences in gain to feed ratio, CTTAD of dry matter and crude protein at both phase I and phase II. Digestibility of gross energy was linearly improved (p<0.05) in phase II. At day 28, pigs fed Ecklonia cava had greater (linear, p<0.05) Lactobacillus spp., fewer Escherichia coli (E. coli) spp. (linear, p<0.05) and a tendency to have fewer cecal Clostridium spp. (p = 0.077). The total anaerobic bacteria were not affected with supplementation of Ecklonia cava in diets. Polynomial contrasts analysis revealed that villus height of the ileum exhibited a linear increase (p<0.05) in response with the increase in the level of dietary Ecklonia cava. However, villus height of duodenum and jejunum, crypt depth, villus height to crypt depth ratio of different segments of the intestine were not affected. Conclusion: The results suggest that Ecklonia cava had beneficial effects on the growth performance, cecal microflora, and intestinal morphology of weanling pigs.

• Journal of Microbiology
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• v.43 no.4
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• pp.345-353
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• 2005

The complex ecosystem of intestinal micro flora is estimated to harbor approximately 400 different microbial species, mostly bacteria. However, studies on bacterial colonization have mostly been based on culturing methods, which only detect a small fraction of the whole microbiotic ecosystem of the gut. To clarify the initial acquisition and subsequent colonization of bacteria in an infant within the few days after birth, phylogenetic analysis was performed using 16S rDNA sequences from the DNA iso-lated from feces on the 1st, 3rd, and 6th day. 16S rDNA libraries were constructed with the amplicons of PCR conditions at 30 cycles and $50^{\circ}C$ annealing temperature. Nine independent libraries were produced by the application of three sets of primers (set A, set B, and set C) combined with three fecal samples for day 1, day 3, and day 6 of life. Approximately 220 clones ($76.7\%$) of all 325 isolated clones were characterized as known species, while other 105 clones ($32.3\%$) were characterized as unknown species. The library clone with set A universal primers amplifying 350 bp displayed increased diversity by days. Thus, set A primers were better suited for this type of molecular ecological analysis. On the first day of the life of the infant, Enterobacter, Lactococcus lactis, Leuconostoc citreum, and Streptococcus mitis were present. The largest taxonomic group was L. lactis. On the third day of the life of the infant, Enterobacter, Enterococcus faecalis, Escherichia coli, S. mitis, and Streptococcus salivarius were present. On the sixth day of the life of the infant, Citrobacter, Clostridium difficile, Enterobacter sp., Enterobacter cloacae, and E. coli were present. The largest taxonomic group was E. coli. These results showed that microbiotic diversity changes very rapidly in the few days after birth, and the acquisition of unculturable bacteria expanded rapidly after the third day.

• IMMUNE NETWORK
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• v.21 no.4
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• pp.25.1-25.16
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• 2021

Asthma is a heterogeneous disease whose development is shaped by a variety of environmental and genetic factors. While several recent studies suggest that microbial dysbiosis in the gut may promote asthma, little is known about the relationship between the recently discovered lung microbiome and asthma. Innate lymphoid cells (ILCs) have also been shown recently to participate in asthma. To investigate the relationship between the lung microbiome, ILCs, and asthma, we recruited 23 healthy controls (HC), 42 patients with non-severe asthma, and 32 patients with severe asthma. Flow cytometry analysis showed severe asthma associated with fewer natural cytotoxicity receptor (NCR)⁺ILC3s in the lung. Similar changes in other ILC subsets, macrophages, and monocytes were not observed. The asthma patients did not differ from the HC in terms of the alpha and beta-diversity of the lung and gut microbiomes. However, lung function correlated positively with both NCR⁺ILC3 frequencies and microbial diversity in the lung. Sputum NCR⁺ILC3 frequencies correlated positively with lung microbiome diversity in the HC, but this relationship was inversed in severe asthma. Together, these data suggest that airway NCR⁺ILC3s may contribute to a healthy commensal diversity and normal lung function.