• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.1
• /
• pp.78-84
• /
• 2017

Objective: The aim of this study was to examine shifts in the composition of the bacterial population in the intestinal tracts (ITs) of weaning piglets by antibiotic treatment using high-throughput sequencing. Methods: Sixty 28-d-old weaning piglets were randomly divided into two treatment groups. The Control group was treated with a basal diet without antibiotics. The Antibiotic group's basal diet contained colistin sulfate at a concentration of 20 g per ton and bacitracin zinc at a concentration of 40 g per ton. All of the pigs were fed for 28 days. Then, three pigs were killed, and the luminal contents of the jejunum, ileum, cecum, and colon were collected for DNA extraction and high-throughput sequencing. Results: The results showed that the average daily weight gain of the antibiotic group was significantly greater (p<0.05), and the incidence of diarrhea lower (p>0.05), than the control group. A total of 812,607 valid reads were generated. Thirty-eight operational taxonomic units (OTUs) that were found in all of the samples were defined as core OTUs. Twenty-one phyla were identified, and approximately 90% of the classifiable sequences belonged to the phylum Firmicutes. Forty-two classes were identified. Of the 232 genera identified, nine genera were identified as the core gut microbiome because they existed in all of the tracts. The proportion of the nine core bacteria varied at the different tract sites. A heat map was used to understand how the numbers of the abundant genera shifted between the two treatment groups. Conclusion: At different tract sites the relative abundance of gut microbiota was different. Antibiotics could cause shifts in the microorganism composition and affect the composition of gut microbiota in the different tracts of weaning piglets.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.11
• /
• pp.1640-1650
• /
• 2020

Colorectal cancer (CRC) is the leading cause of common malignant neoplasm worldwide. Many studies have analyzed compositions of gut microbiota associated with various diseases such as inflammatory bowel diseases (IBD) and colon cancer. One of the most representative bacteria involved in CRC is enterotoxigenic Bacteroides fragilis (ETBF), a species belonging to phylum Bacteroidetes. We used ETBF colonized mice with azoxymethane (AOM)/dextran sulphate sodium (DSS) and zerumbone, a compound with anti-bacterial effect, to determine whether zerumbone could restore intestinal microbiota composition. Four experimental groups of mice were used: sham, ETBF colonized AOM/DSS group, ETBF colonized AOM/DSS group zerumbone 60 mg kg-1 (ETBF/AOM/DSS + Z (60)), and only zerumbone (60 mg kg^-1)-treated group. We performed reversible dye terminators-based analysis of 16S rRNA gene region V3-V4 for group comparison. Microbiota compositions of ETBF/AOM/DSS + Z (60) group and ETBF colonized AOM/DSS group not given zerumbone were significantly different. There were more Bacteroides in ETBF/AOM/DSS + Z (60) group than those in ETBF colonized AOM/DSS group, suggesting that B. fragilis could be a normal flora activated by zerumbone. In addition, based on linear discriminant analysis of effect size (LEfSe) analysis, microbial diversity decreased significantly in the ETBF colonized AOM/DSS group. However, after given zerumbone, the taxonomic relative abundance was increased. These findings suggest that zerumbone not only influenced the microbial diversity and richness, but also could be helpful for enhancing the balance of gut microbial composition. In this work, we demonstrate that zerumbone could restore the composition of intestinal microbiota.

• Journal of Soil and Groundwater Environment
• /
• v.20 no.7
• /
• pp.121-134
• /
• 2015

Spatial and temporal changes in algal population in Yongdam reservoir and ecological factors that induced the changes in the size and composition of algal population were investigated by monthly sampling at ten locations in the reservoir. Nutritional state of the reservoir was identified to be phosphorus-limited with nitrogen to phosphorus (N : P) ratio much greater than 17 in most samples. Algal population was dominated by three taxonomic groups, diatoms, chlorophytes and cyanobacteria. Although explosive algal growth was not observed in the summer, algal population showed transition with time of the dominant algal type from diatoms in the winter to cyanobacteria in the summer. Chlorophyta was not the dominant group in the reservoir although they maintained relatively stable number of cells in the reservoir and showed increase in population from March to May. The application of statistical methods revealed that the factors inducing changes in cell number of each group were water temperature for diatoms and cyanobacteria and phosphorus concentration for chlorophyte. Fluctuation of cyanobacterial population was mainly observed near the inlet of tributaries while diatoms showed higher variation inside the reservoir.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.9
• /
• pp.858-868
• /
• 2009

The abundance, biomass, size distribution, and taxonomic composition of bacterial and protistan (heterotrophic and autotrophic nanoflagellates and ciliates) communities were investigated in six lakes of Masurian Lake District (north-eastern Poland) differing in trophic state. Samples were taken from the trophogenic water layer during summer stratification periods. Image analysis techniques with fluorescent in situ hybridization (FISH) as well as [$^3H$]-methyl-thymidine incorporation methods were applied to analyze differences in the composition and activity of bacterial communities. The greatest differences in trophic parameters were found between the humic lake and remaining non-humic ones. The same bacterial and heterotrophic nanoflagellate (HNF) cell size classes dominated in all the studied lakes. However, distinct increases in the contributions of large bacterial (>$1.0{\mu}m$) and HNF (>$10{\mu}m$) cells were observed in eutrophic lakes. The bacterial community was dominated by the ${\beta}$-Proteohacteria group, which accounted for 27% of total DAPI counts. Ciliate communities were largely composed of Oligotrichida. Positive correlations between bacteria and protists, as well as between nanoflagellates (both heterotrophic and autotrophic) and ciliates, suggest that concentrations of food sources may be important in determining the abundance of protists in the studied lakes.

• Journal of Ecology and Environment
• /
• v.38 no.3
• /
• pp.389-395
• /
• 2015

The composition of the Martes flavigula diet has been extensively studied, but little is known about its insect component. This study characterized the insect diet and insect nest materials in the feces of M. flavigula. A total of 952 fecal samples were collected in Jirisan National Park from January 2009 to November 2011, and 1379 species or taxonomic groups were identified. M. flavigula fed on insects (8.7%) and bee wax (5.0%), which comprised 2.9% and 4.4% of the dry weight of M. flavigula feces, respectively. A total of 12 insect species belonging to 8 families in 3 orders were identified. The most frequently found insects were Hymenoptera (frequency of occurrence, FO, 89.1), including Vespa simillima simillima (FO, 37.3) and Vespula koreensis koreensis (FO, 20.0). The Vespidae constituted the majority of the insect diet in autumn when the diversity of marten's prey was strongly reduced, probably because the numbers of social insects were sufficient for M. flavigula. In addition, the data suggest that M. flavigula attacks the nests of social wasps in late autumn when males do not have a venomous sting and new queens are less aggressive than workers. Bee wax appeared in all seasons and the highest rate was from spring to early summer. However, the remains of honeybees were not found in feces; thus, M. flavigula presumably eats honey but not honeybees.

• Korean journal of applied entomology
• /
• v.14 no.4 s.25
• /
• pp.209-213
• /
• 1975

This paper is a report of studies to determine the amino acid composition of Plant Pathogenic Corynebacteria and to assess whether these characteristics can be correlated with the taxonomic position of these organisms. The results indicated that plant pathogenic Corynebacteria contained on average less cystein, trypthophane, histidine, phenylalanine, isoleucin and total protein than did the other genera of bacteria. However, in general, the quantities of both cell protein and amino acids contained in bacterial cells were characteristics of the species or an individual strain of the organism and were not related to its classification.

• The Korean Journal of Mycology
• /
• v.48 no.3
• /
• pp.251-271
• /
• 2020

Diversity and community composition of bulb-associated fungi of Fritillaria Cirrhosae Bulbus source plants, which are used in traditional chinese medicine, in the eastern Himalaya-Hengduan Mountains, southwestern China, were estimated based on the internal transcribed spacer rDNA sequence analysis, using host plant species, geographic area, and plant phenology as variables. A total of 1,486 fungal sequences assigned to 251 operational taxonomical units (OTUs) were obtained from the bulbs. Fungal OTUs comprised 96.41% Ascomycotina, 3.52% Basidiomycotina, and 0.07% Zygomycotina. Sordariomycetes, Hypocreales, and Nectriaceae were the most frequent fungal lineages at each taxonomic rank. Fusarium, Ilyonectria, Tetracladium, Leptodontidium, and Tomentella were the top OTU-rich genera. Fusarium sp. 03, Ilyonectria rufa, Fusarium sp. 08, Ilyonectria sp. 03, and Leptodontidium orchidicola 03 represented the most frequent OTUs. Fusarium spp. were the most frequent general taxa. The distribution of fungal community exhibited preferences for host plant species, geographic area, and plant phenology. These findings are the foundation of our research on culturing and active metabolites of bulb-associated fungi of Fritillaria Cirrhosae Bulbus source plants.

• Journal of Environmental Science International
• /
• v.21 no.3
• /
• pp.313-326
• /
• 2012

Three embankments, namely Changpo, Bokkil and Guil, in Chunggye Bay were investigated to assess the influence of environmental changes to phytoplankton size structure, distribution of species and standing crops. Three stations was sampled near at each embankment in Nov. 2006, Feb. 2007, May 2007 and Aug. Phytoplankton were classified into net-size (>20${\mu}m$) and nano-size (<20${\mu}m$). In summer, the freshwater discharge seemed to have influence in the decrease of salinity and in the increase of turbidity, ammonium and phosphorus concentrations. Chl a concentration and phytoplankton abundance in Feb. 2007 were observed to be generally higher in all stations compared to other periods. Net-size phytoplankton was observed to be higher in Feb. 2007 and May 2007 compared to nano-sized phytoplankton. However, there was shift in phytoplankton composition in Nov. 2006 and Aug. 2007. Phytoplankton under seven class (Bacillariophyceae, Chlorophyceae, Chrysophyceae, Cryptophyceae, Cyanophyceae, Dinophyceae, Euglenophyceae) was identified during the study period. It was found out that the major phytoplankton class was Bacillariophyceae. Phytoplankton was more diverse in autumn compared to any other season. Cyanophyceae was increased in summer. In rainy season, change in physical factors (salinity, transparency) seemed to have more influence on phytoplankton growth compared to inorganic nutrients.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.7
• /
• pp.978-989
• /
• 2021

Allyl isothiocyanate (AITC), as a fumigant, plays an important role in soil control of nematodes, soil-borne pathogens, and weeds, but its effects on soil microorganisms are unclear. In this study, the effects of AITC on microbial diversity and community composition of Capsicum annuum L. soil were investigated through Illumina high-throughput sequencing. The results showed that microbial diversity and community structure were significantly influenced by AITC. AITC reduced the diversity of soil bacteria, stimulated the diversity of the soil fungal community, and significantly changed the structure of fungal community. AITC decreased the relative abundance of dominant bacteria Planctomycetes, Acinetobacter, Pseudodeganella, and RB41, but increased that of Lysobacter, Sphingomonas, Pseudomonas, Luteimonas, Pseudoxanthomonas, and Bacillus at the genera level, while for fungi, Trichoderma, Neurospora, and Lasiodiplodia decreased significantly and Aspergillus, Cladosporium, Fusarium, Penicillium, and Saccharomyces were higher than the control. The correlation analysis suggested cellulase had a significant correlation with fungal operational taxonomic units and there was a significant correlation between cellulase and fungal diversity, while catalase, cellulose, sucrase, and urease were the major contributors in the shift of the community structure. Our results will provide useful information for the use of AITC in the assessment of environmental and ecological security.

• Journal of Conservation Science
• /
• v.37 no.4
• /
• pp.357-361
• /
• 2021

In order to determine the changes in microbial community due to termites, soil microorganisms surrounding the termites were investigated. First, bacterial communities from soil with termites collected at Seonamsa temple, Suncheon city, Korea were compared by next-generation sequencing (NGS, Illumina Miseq). The bacterial composition of soil from Daeungjeon without termites and the soil from Josadang, Palsangjeon, and Samjeon with termites were compared. Next, the bacterial composition of these soils was also compared with that of humus soil cultured with termites. A total high-quality sequences of 71,942 and 72,429 reads were identified in Seonamsa temple's soil and humus soil, respectively. The dominant phyla in the collected Seonamsa temple's soil were Proteobacteria (27%), Firmicutes (24%) and Actinobacteria (21%), whereas those in the humus soil were Bacteriodetes (56%) and Proteobacteria (37%). Using a two-dimensional plot to explain the principal coordinate analysis of operational taxonomic unit compositions of the soil samples, it was confirmed that the samples were divided into soil with and without termites, and it was especially confirmed that the Proteobacteria phylum was increased in humus soil with termites than in humus soil without termites.