• Journal of Life Science
• /
• v.28 no.6
• /
• pp.688-696
• /
• 2018

Hemp seed (Cannabis sativa L.; HS), an annual herbaceous plant in the Cannabis genus, has been reported to play various biological functions in immunity increase, atherosclerosis, constipation, hyperlipidemia prevention, anti-inflammatory, and anti-cancer. In recently years, as superfood, the growing interest in the health care benefits of hemp seed has led to increased consumption. In this study, we investigated the effect of an ethanol extract of HS fermented with lactic acid bacteria (Lactobacillus plantarum KCTC 3107, L. plantarum KCTC 3108, L. brevis BHN-LAB128, L. paracasei BHN-LAB129). An antibacterial activity against Staphylococcus aureus and Bacillus cereus were 13.99 mm and 15.17 mm, respectively. The ethanol extracts of fermented hemp seed by lactic acid bacteria that the contents of total polyphenol, total flavonoid content, DPPH radical scavenging activity, SOD-like activity, and ${\alpha}$-glucosidase inhibitory activity were increased compared to non-fermented hemp seed. Also, tyrosinase inhibitory activity of the fermented hemp seed (FHS), known to melanin increasing substance was increased. In these results, we suggested that FHS have effects of anti-oxidant, ${\alpha}$-glucosidase inhibitory activity, and tyrosinase inhibitory activity. Hence, we proposed that FHS has possible to development as functional foods and cosmetics.

• Korean Journal of Microbiology
• /
• v.47 no.1
• /
• pp.66-73
• /
• 2011

Bacterial density distributions of gut microbes in the digestive organs of Harmonia axyridis collected from three different sources (JK, CK, and CJ) were $6.0{\times}10^4$ CFU/gut under aerobic culture condition and $8.0{\times}10^6$ CFU/gut under anaerobic culture condition. Seven colony types were observed under aerobic condition and three types of similarity were detected under anaerobic condition. In total, 116 strains, including 34 strains under aerobic condition, were isolated from the digestive organs of H. axyridis. Based on the analysis of the 16S rRNA gene sequence, aerobic gut microbes were assigned to the Proteobacteria, Actinobacteria, Firmicutes, and Deinococcus-Thermus. A large number of isolates belonged to the genus Bacillus and Staphylococcus of the Firmicutes commonly found in H. axyridis from different sites. Anaerobic gut microbes were found to be similar according to colony morphological, phylogenetic analysis using ARDRA. Eighty-two anaerobic gut microbes were clustered into 17 different ARDRA types according to HaeIII. Representative anaerobic gut microbes in each ARDRA group were divided into five species of ${\gamma}$-Proteobacteria based on 16S rRNA gene sequence analysis; Hafnia alvei, Enterobacter ludwigii, Enterobacter kobei, Pseudomonas oryzihabitans and Pseudomonas koreensis. Phylogenetic analysis indicated that about 70% of the isolates belonged to ${\gamma}$-Proteobacteria, suggesting predominance of gut microbes.

• Korean Journal of Microbiology
• /
• v.49 no.3
• /
• pp.297-300
• /
• 2013

EPS producing bacteria were enumerated in ginseng root system (rhizosphere soil, rhizoplane, inside of root). EPS producing bacterial density of rhizosphere soil, rhizoplane and inside of root were distributed $9.0{\times}10^6$ CFU/g, $7.0{\times}10^6$ CFU/g, and $1.4{\times}10^3$ CFU/g, respectively. Phylogenetic analysis of the 24 EPS producing isolates based on the 16S rRNA gene sequences, EPS producing isolates from rhizosphere soil (RS) belong to genus Arthrobacter (6 strains) and Rhizobium (1 strain). EPS producing bacteria from rhizoplane (RP) were Arthrobacter (6 strains), Rhodococcus (1 strain) and Pseudomonas (1 strain). EPS producing bacteria from inside of root (IR) were categorized into Rhzobium (6 strains), Bacillus (1 strain), Rhodococcus (1 strain), and Pseudomonas (1 strain). Phylogenetic analysis indicated that Arthrobacter may be a member of representative EPS producing bacteria from ginseng rhizosphere soil and rhizoplane, and Rhizobium is typical EPS producing isolates from inside of ginseng root. The yield of EPS was 10.0 and 4.9 g/L by Rhizobium sp. 1NP2 (KACC 17637) and Arthrobacter sp. 5MP1 (KACC 17636). The purified EPS were analyzed by Bio-LC and glucose, galactose, mannose and glucosamine were detected. The major EPS sugar of these strains was glucose (72.7-84.9%).

• Microbiology and Biotechnology Letters
• /
• v.43 no.2
• /
• pp.142-149
• /
• 2015

Bioaerosols are comprised of particles 0.02-100 μm in size that originate in natural and artificial environments, and as a result of human activities. They consist of microorganisms including viruses, bacteria, fungi, and protozoa; fungal spores; microbial toxins; pollen; plant or animal material; expectorated liquid from humans; and glucans (peptidoglycan and β-glucan). Bioaerosols can cause respiratory and other diseases in humans and animals. In this study, bioaerosol samples acquired from agricultural sources, livestock, a sewage treatment plant, a beach, and a pristine area were analyzed to identify and phylogenetically characterize culturable microorganisms. The isolated bacteria exhibited regional differences, with different species dominating. However, Bacillus cereus was isolated in all samples, with a total of 31 strains isolated from all areas, and Acinetobacter baumannii was isolated from an indoor poultry farm. In addition, bacteria determined to be of novel genus or species of the genera Domibacillus, Chryceobacterium, Nocardioides and family Comamonadaceae were isolated from the agricultural, livestock and beach environments.

• Microbiology and Biotechnology Letters
• /
• v.36 no.4
• /
• pp.268-275
• /
• 2008

In order to develop the multi-functional rhizobacteria that can exert positive effect on the growth of plants growing in the coastal sand dune located along East Coast of Korea, rhizospheral bacteria of 11 different plants from this area were isolated 1,330 rhizobacteria. Among these, 23 strains were able to produce auxin and had spectrum of antagonism toward various phytopathogenic microbes. To know the mechanism of this antifungal activity, these 23 strains were subjected to further analyses; 19 strains of these produced siderophore as determined by color reaction on CAS-blue plate, 4 strains produced antifungal cellulase as judged by color change on CMC-Congo red plate, 17 strains were able to utilized insoluble phosphate salts, also determined by clear zone formation on PVK medium. Identification of the strain was assigned to all 23 strains by l6s rDNA sequence analysed, and all were identified to be in the genus of Bacillus and Pseudomonas. One strain of these, denoted Pseudomonas fluorescens IB4-14, showed ACC deaminase activity which is known to be involved in the resistance of environmental stress such as salt and drought. Also, P. fluorescens IB4-l4 showed the germination stimulation and roots growth promoting activity on the in vivo assay of Lysimachia mauritiana Lam. (spoonleaf yellow loosestrife).

• Microbiology and Biotechnology Letters
• /
• v.46 no.2
• /
• pp.127-134
• /
• 2018

In this study, 79 bacterial isolates were collected from the surface of marine algae Umbraulva japonica. As a result of analysis of 16s rRNA gene sequence, the 79 isolated bacteria were divided into 4 major groups: [Proteobacteria (74.69%), Actinobacteria (2.53%), Fimicutes (2.53%), and Bacteroidetes (20.25%)] - 7 classes (Actinobacteria, Flavobacteria, Sphingobacteria, Baciili, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria), 12 orders, 17 families and 31 genera. The newly isolated 3 strains could be novel species because of less than 97% similarity in 16s rRNA sequence. Therefore, it is considered that additional experiments should be conducted together with the standard strain. Analysis of 79 bacterial antibacterial activity against human and fish pathogens, such as Edwardsiella tarda, Vibrio harveyi, Streptococcus iniae, Steptococcus parauberis, Escherichia coli, Steptococcus mutans, Listeria monocytogenes and Vibrio vulnificus, was performed by using the supernatant liquid and pellet. As a result, pellet of UJT9, UJT20 and UJR17 showed antibacterial activity against V. vulnificus, UJR17 also showed antibacterial activity against S. parauberis. UJT7 and UJT20, UJR17 have been identified as Bacillus sp. and Pseudomonas sp. and it may be safely assented that it's beneficial to carry out additional experiments for various applications.

• Microbiology and Biotechnology Letters
• /
• v.46 no.2
• /
• pp.102-110
• /
• 2018

A bacterial strain capable of metabolizing myo-inositol (MI) and converting to other substances was isolated from soil of orchard. The isolate, named YB-46, was grown on minimal medium supplemented with MI as the sole carbon source and was presumed to belonging to genus Enterobacter according to the 16S rDNA sequence. Escherichia coli transformant converting MI into unknown metabolites was selected from a metagenomic library prepared with fosmid pCC1FOS vector. Plasmid was isolated from the transformant, and the inserted gene was partially sequenced. From the nucleotide sequence, an iolG gene was identified to encode myo-inositol dehydrogenase (IolG) consisting of 336 amino residues. The IolG showed amino acid sequence similarity of about 50% with IolG of Enterobacter aerogenes and Bacillus subtilis. The His-tagged IolG (HtIolG) fused with hexahistidine at C-terminus was produced and purified from cell extract of recombinant E. coli. The purified HtIolG showed maximal activity at $45^{\circ}C$ and pH 10.5 with the highest activity for MI and D-glucose, and more than 90% of maximal activity for D-chiro-inositol, D-mannitol and D-xylose. $K_m$ and $V_{max}$ values of the HtIolG for MI were 1.83 mM and $0.724{\mu}mol/min/mg$ under the optimal reaction condition, respectively. The activity of HtIolG was increased 1.7 folds by $Zn^{2+}$, but was significantly inhibited by $Co^{2+}$ and SDS.

• Korean Journal of Microbiology
• /
• v.51 no.4
• /
• pp.448-452
• /
• 2015

The bacterial strain that was isolated from chinese cabbage rhizosphere, showed inhibition of yeast growth. This strain was identified as Pseudomonas fluorescens BB2 by API 20NE test and 16S rRNA gene sequence analysis. P. fluorescens BB2 strain produced antibiotics against yeast as a secondary metabolite effectively when the culture was carried out in YM medium with 3% glucose at $20^{\circ}C$. The protein antibiotic of BB2 strain which was concentrated by ammonium sulfate precipitation and n-butanol extraction inhibited the growth of yeast with the minimal inhibitory concentration of $10{\mu}g/ml$ against Candida albicans KCTC 7965, and the growth of yeast was completely inhibited at $80{\mu}g/ml$. The hydrophilic fraction of n-butanol extraction inhibited the growth of Bacillus cereus ATCC 21366, showed orange halo on chrome azurol S plate, which means the fraction contained iron chelating siderophore. The results of crystal violet uptake through the cell membrane showed that membrane permeability was increased about 9% than control, when the concentration of hydrophobic antibiotic against yeast C. albicans was $60{\mu}g/ml$. As a result, the antibiotic produced by P. fluorescens BB2 against yeast Candida is considered antimicrobial peptide, and this is the first report in the genus Pseudomonas.

• Horticultural Science & Technology
• /
• v.31 no.6
• /
• pp.657-665
• /
• 2013

A large patch disease caused by Rhizoctonia solani AG2-2 (IV) is a serious problem in Korean lawngrass (Zoysia japonica) sites including golf courses and sports fields in Korea. Antagonistic microorganisms against R. solani AG2-2 (IV) were isolated from various forest and crop soil sources in Southern Korea. Among the 61 isolates, I-009, FRIN-001-1, and YPIN-022 strains showing dramatic inhibition of the mycelial growth of R. solani AG2-2 (IV) in the pairing culture were selected as the most potential antagonistic microorganisms for this study. Based on the 16s RNA sequence comparison, I-009 and FRIN-001-1 isolates were identified as Bacillus spp., while YPIN-022 isolate belongs to the genus Pseudomonas. The greater inhibition (clear) zone between two edges of the selected and pathogenic microbes ranged from 11 to 15 mm in three selections, but the others averaged to 7 mm out of 30 mm distance. In another antifungal test using culture filtrate, those three isolates represented a range of 51.7 to 63.5% suppression potential. The selected isolates also inhibited significantly the stem-segment colonization by R. solani AG2-2 (IV) in vivo test by 28.1%, 43.0%, and 23.7% when inoculated with I-009, FRIN-001-1, and YPIN-022, respectively. The highest antagonistic activity for the large patch disease was demonstrated by the isolate FRIN-001-1, which will be useful for developing a bio-pesticide against Rhizoctonia.

• Journal of Life Science
• /
• v.25 no.2
• /
• pp.189-196
• /
• 2015

Bacterial diversity was studied in the rhizosphere of Suaeda japonica Makino, which is native to Suncheon Bay in South Korea. Soil samples from several sites were diluted serially, and pure isolation was performed by subculture using marine agar and tryptic soy agar media. Genomic DNA was extracted from 29 pure, isolated bacterial strains, after which their 16S rDNA sequences were amplified and analyzed. Phylogenetic analysis was performed to confirm their genetic relationship. The 29 bacterial strains were classified into five groups: phylum Firmicutes (44.8%), Gamma proteobacteria group (27.6%), Alpha proteobacteria group (10.3%), phylum Bacteriodetes (10.3%), and phylum Actinobacteria (6.8%). The most widely distributed genera were Bacillus (phylum Firmicutes), and Marinobacterium, Halomonas, and Vibrio (Gamma proteobacteria group). To confirm the bacterial diversity in rhizospheres of S. japonica, the diversity index was used at the genus level. The results show that bacterial diversity differed at each of the sampling sites. These 29 bacterial strains are thought to play a major role in material cycling at Suncheon Bay, in overcoming the sea/mud flat-specific environmental stress. Furthermore, some strains are assumed to be involved in a positive interaction with the halophyte S. japonica, as rhizospheric flora, with induction of growth promotion and plant defense mechanism.