• Korean Journal of Microbiology
• /
• v.49 no.4
• /
• pp.415-418
• /
• 2013

Since the development of the next generation sequencing (NGS) technology, 16S rRNA gene sequencing has become a major tool for microbial community analysis. Recently, human microbiome project (HMP) has been completed to identify microbes associated with human health and diseases. HMP achieved characterization of several diseases caused by bacteria, especially the ones in human gut. While human intestinal bacteria have been well characterized, little have been studied about other animal intestinal bacteria. In this study, we surveyed diversity of livestock animal fecal microbiota and discuss importance of studying fecal microbiota. Here, we report the initiation of the fecal microbiome project in South Korea.

• Journal of dental hygiene science
• /
• v.19 no.2
• /
• pp.77-85
• /
• 2019

In the past gut microbiome has been the main focus of microbiome research. Studies about the microbiome inside oral cavities and other organs are underway. Studies about the relationship between noninfectious diseases and periodontal diseases, and the negative effects of harmful oral microbes on systemic health have been published in the recent past. A lot of attention is being paid towards fostering a healthy oral microbial ecosystem. This study aimed to understand the roles and effects of the microbiome inside the human body can potentially help cure various diseases including inflammatory bowel diseases with no known cure such as Crohn's disease, atopic dermatitis, obesity, cancer, diabetes, brain diseases and oral diseases. The present study examined technological trends in the correlation between the human microbiome and diseases in the human body, interactions between the human body's immunity, the metabolic system, and the microbiome, and research trends in other countries. While it has been proven that human microbiome is closely correlated with human diseases, most studies are still in the early stage of trying to compare the composition of microbiomes between health and patient groups. Since the oral environment is a dynamic environment that changes due to not only food intake but also other external factors such as lifestyle, hygiene, and drug intake, it is necessary to continue in-depth research on the microbiome composition characteristics to understand the complex functions of oral microorganisms. Analyzing the oral microbiome using computational technology may aid in disease diagnosis and prevention.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.8_spc
• /
• pp.1321-1330
• /
• 2019

Recent development of novel techniques in systems biology have been used to improve and manipulate the rumen microbial ecosystem and gain a deeper understanding of its physiological and microbiological interactions and relationships. This provided a deeper insight and understanding of the relationship and interactions between the rumen microbiome and the host animal. New high-throughput techniques have revealed that the dominance of Proteobacteria in the neonatal gut might be derived from the maternal placenta through fetal swallowing of amniotic fluid in utero, which gradually decreases in the reticulum, omasum, and abomasum with increasing age after birth. Multi "omics" technologies have also enhanced rumen fermentation and production efficiency of dairy goats using dietary interventions through greater knowledge of the links between nutrition, metabolism, and the rumen microbiome and their effect in the environment. For example, supplementation of dietary lipid, such as linseed, affects rumen fermentation by favoring the accumulation of ${\alpha}$-linolenic acid biohydrogenation with a high correlation to the relative abundance of Fibrobacteriaceae. This provides greater resolution of the interlinkages among nutritional strategies, rumen microbes, and metabolism of the host animal that can set the foundation for new advancements in ruminant nutrition using multi 'omics' technologies.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.4
• /
• pp.261-272
• /
• 2021

Doxorubicin (Dox) is widely used to the treatment of cancer, however, it could cause damage to gastric mucosa. To investigate the protective effects and related mechanisms of coenzyme Q10 (CoQ10) and vitamin C (VC) on Dox-induced gastric mucosal injury, we presented the survey of the 4 groups of the rats with different conditions. The results showed Dox treatment significantly induced GES-1 apoptosis, but preconditioning in GES-1 cells with VC or CoQ10 significantly inhibited the Dox-induced decrease and other harm effects, including the expression and of IκKβ, IκBα, NF-κB/p65 and tumor necrosis factor (TNF-α) in GES-1 cells. Moreover, high-throughput sequencing results showed Dox treatment increased the number of harmful gut microbes, and CoQ10 and VC treatment inhibited this effect. CoQ10 and VC treatment inhibits Dox-induced gastric mucosal injury by inhibiting the activation of the IkKB/IκBα/NF-κB/p65/TNF-α pathway, promoting anti-inflammatory effects of gastric tissue and regulating the composition of the intestinal flora.

• Microbiology and Biotechnology Letters
• /
• v.51 no.3
• /
• pp.250-256
• /
• 2023

Cannabis sativa (CS) has been in the spotlight not only for its medical uses but also as a raw material for cosmetics. As fermented cosmetics are known to have various health benefits, they have been extensively researched. Here, we investigated the characteristics of CS stems fermented using various gut microbes. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay and melanin content analysis revealed that melan-a cells containing CS stems fermented with Weissella paramesenteroides (CSWP) showed considerably reduced melanin content. Additionally, CSWP downregulated the expression of several melanogenesis factors, tyrosinase-related protein-1, and tyrosinase-related protein-2. This study suggests that the anti-melanogenic effect of CSWP could provide a new basis for the development of skin-lightening agents.

• Korean Journal of Microbiology
• /
• v.51 no.3
• /
• pp.241-248
• /
• 2015

Although studies on probiotics have been performed mostly with viable microbes, the beneficial functions of dead or heat-killed form of probiotic strains have also been examined. In this study, live and heat-killed forms of Lactobacillus acidophilus CBT LA1 were investigated in vitro and in vivo to evaluate the properties necessary for gut barrier protection. Cell surface hydrophobicity (CSH), autoaggregation (AA), cell adhesion, and lipopolysaccharide (LPS)-binding properties were evaluated. In addition, the suppressive effect on LPS-induced interleukin (IL)-8 expression was investigated in HT-29 cells. To identify optimal conditions for CBT LA1 to adhere to HT-29 cells, CBT LA1 cells were heat-treated at 80, 85, 90, 95, 100, or $121^{\circ}C$ for 10 min; cells treated at $80^{\circ}C$ for 10 min showed the highest adhesion. Heat-killed bacteria at $80^{\circ}C$ showed higher levels of LPS-binding, CSH, AA, adhesion to HT-29, and suppression of IL-8 expression than did live CBT LA1. In vivo imaging was performed to evaluate the ability of live or heat-killed CBT LA1 to remove LPS from the intestine in a rat model of infection. At 16 h after infection, fluorescence from FITC-conjugated LPS had mostly disappeared from the intestine of the rats administered with live or heat-killed CBT LA1; the effect was greater with heat-killed CBT LA1 at $80^{\circ}C$. These results suggest that heat-killed CBT LA1 as well as its live form can be applied as a pharmabiotic for protection of the gut barrier.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.1
• /
• pp.114-121
• /
• 2012

The potential for ochratoxin A (OTA) degradation by swine intestinal microbiota was assessed in the current study. Intestinal content that was collected aseptically from swine was spiked with 100 ppb OTA and incubated for 6 and 12 h at $39^{\circ}C$. An OTA assay was conducted using the incubated samples, and it was found that 20% of the OTA toxin was detoxified, indicating the presence of microbes capable of OTA degradation. Twenty-eight bacterial species were isolated anaerobically in M 98-5 media and 45 bacterial species were isolated using nutrient broth aerobically. Screening results showed that one anaerobic bacterial isolate, named MM11, detoxified more than 75% of OTA in liquid media. Furthermore, 1.0 ppm OTA was degraded completely after 24 h incubation on a solid 'corn' substrate. The bacterium was identified by 16S rDNA sequencing as having 97% sequence similarity with Eubacterium biforme. The isolation of an OTA-degrading bacterium from the swine natural flora is of great importance for OTA biodegradation and may be a valuable potential source for OTA-degradation enzymes in industrial applications.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.1
• /
• pp.8-13
• /
• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• Journal of Animal Science and Technology
• /
• v.63 no.6
• /
• pp.1423-1432
• /
• 2021

To elucidate the role and mechanism of microbes, we combined culture-dependent and culture-independent approaches to investigate differences in gut bacterial composition between sows and weaned pigs. Under anaerobic conditions, several nonselective and selective media were used for isolation from fecal samples. All isolated bacteria were identified and classified through 16S rRNA sequencing, and the microbiota composition of the fecal samples was analyzed by metagenomics using next generation sequencing (NGS) technology. A total of 278 and 149 colonies were acquired from the sow and weaned pig fecal samples, respectively. Culturomics analysis revealed that diverse bacterial genus and species belonged to Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes were isolated from sow and weaned pigs. When comparing culture-dependent and culture-independent analyses, 191 bacterial species and 2 archaeal bacterial species were detected through culture-independent analysis, and a total of 23 bacteria were isolated through a culture-dependent approach, of which 65% were not detected by metagenomics. In conclusion, culturomics and metagenomics should be properly combined to fully understand the intestinal microbiota, and livestock-derived microbial resources should be informed by culturomic approaches to understand and utilize the mechanism of host-microbe interactions.

• Journal of Animal Science and Technology
• /
• v.65 no.6
• /
• pp.1270-1289
• /
• 2023

This study evaluates how different feeding systems impact ruminal fermentation, methane production, and microbiota of Hanwoo steers native to Korea. In a replicated 2 × 2 crossover design over 29 days per period, eight Hanwoo steers (507.1 ± 67.4 kg) were fed twice daily using a separate feeding (SF) system comprising separate concentrate mix and forage or total mixed rations (TMR) in a 15:85 ratio. The TMR-feeding group exhibited a considerable neutral detergent fiber digestibility increase than the SF group. However, ruminal fermentation parameters and methane production did not differ between two feeding strategies. In addition, TMR-fed steers expressed elevated Prevotellaceae family, Christensenellaceae R-7 group, and an unidentified Veillonellaceae family genus abundance in their rumen, whereas SF-fed steers were rich in the Rikenellaceae RC9 gut group, Erysipelotrichaceae UCG-004, and Succinivibrio. Through linear regression modeling, positive correlations were observed between the Shannon Diversity Index and the SF group's dry matter intake and methane production. Although feeding systems do not affect methane production, they can alter ruminal microbes. These results may guide future feeding system investigations or ruminal microbiota manipulations as a methane-mitigation practice examining different feed ingredients.