• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.280-287
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• 2000

Three antimicrobial compounds (SL-l, SL-2 and SL-3) were isolated and identified from the marine red alga, Symphyocladia latiuscula. In addition, their biological functionalities such as cytotoxicity and desmutagenic activity were investigated. From the cryophyllized S. JatiuscuJa, SL-l, SL-2 and SL-3 were purified by solvent extractions and HPLC.SL-2 was crystallized in benzene-diethyl ether solvent. On the EI-MS spectra, it was found that they had three bromines in their structure which showed typical signal strength ratios at $M^+, [M+2]^+, [M+4]^+, [M+6]^+ (13: 38: 37: 12)$. $SL-l$ was identified as 2,3,6-tribromo-4,5-dihydroxybenzyl alcohol ($C_8H_7Br_3O_3, MW=374$) by NMR and MS spectra. SL-2 was assigned as 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether ($C_8H_7Br_3O_3, MW=388$) and confirmed by X-ray crystallographic analysis. SL-3 was presumed as an isomer of SL-2. Methanol extract of the S. latiuscula showed antimicrobial activities against all strains tested (bacteria, 15 strains; yeasts, 17 strains; fungi, 4 strains), much or less. The strongest inhibition activity of the methanol extract was to the Vibrio mimicus ($50 {\mu}g/ml$) and V. vulnificus ($50 {\mu}g/ml$). The mice injected intraperitoneally with 3 mg of SL-l and 5 mg of 5L-2 showed no acute toxicity response. SL-2 showed higher desmutagenic activity than SL-l against PhIP and MeIQx.

• Biomedical Science Letters
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• v.18 no.2
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• pp.146-151
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• 2012

Urinary tract infection (UTI) is one of the most common bacterial infections and is predominantly caused by uropathogenic Escherichia coli (UPEC). UPEC strains generally possess several genes encoding virulent factors, which are mostly adhesins, toxins, bacteriocin and siderophores. E. coli is composed of four main phylogenetic group (A, B1, B2, D) and virulent extra-intestinal strains mainly belong to groups B2 and D. Prescription of ciprofloxacin, a kind of fluoroquinolone group antibiotics, is increasing now a days, but resistance to this drug is also increasing. A total of 188 strains of E. coli were collected. Thirteen strains were collected from healthy students in 2011 and 175 strains from patients with urinary tract infection in 2010. Virulence factor genes (papC, fimG/H, sfaD/E, hlyA, cnf1, and usp) were amplified by polymerase chain reaction (PCR) methods for phylogenetic group (A, B1, B2, D) detection. Ciprofloxacin susceptibility test was performed by disk diffusion method. The identified virulence factors (VFs), phylogenetic groups and ciprofloxacin resistance in 13 E. coli strains isolated from healthy students were papC (15.4%), fimG/H (76.9%), sfaD/E (30.8%), hlyA (23.1%), cnf1 (23.1%), usp (7.7%), phylogenetic group A (23%), B1 (8%), B2 (46%), D (23%) and ciprofloxacin resistance (7.7%), while those of in 175 E. coli strains isolated from patients with UTI were papC (41.1%), fimG/H (92.5%), sfaD/E (30.3%), hlyA (10.3%), cnf1 (30.3%), usp (27.4%), phylogenetic group A (9.1%), B1 (5.1%), B2 (60.6%), D (25.1%) and ciprofloxacin resistance (29.7%). In this study, 10 out of 13 E. coli strains (76.9%) from healthy students were found to possess more than one virulence factor associated with adhesion. In addition, one E. coli strain isolated from healthy students who had never been infected with UPEC showed ciprofloxacin resistance. According to these results between the virulence factors and phylogenetic groups it was closely associated, and UPEC strains isolated from patients showed high level of ciprofloxacin resistance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.1
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• pp.17-21
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• 2001

Soybean mosaic virus (SMV) resistance of Korean recommended soybeans was evaluated naturally and by mechanical inoculation in Suwon. Based on the differential reaction of forty-four soybean genotypes tested to nine different SMV strains, soybeans were classified into twenty-four groups. Myeongjunamulkong and Ilpumgeom-jeongkong showed a high degree of resistance to nine SMV strains, having no symptom. The other cultivars produced various reactions according to inoculation of each SMV strain: symptomless, mosaic or systemic necrosis. Only five cultivars such as Kwangankong, Eunhakong, Tawonkong, Namhaekong, Sobaegnamulkong were totally susceptible to every strain. There was variation in disease incidence. Soybeans, having the highest levels of resistance to G5H and G7H in the greenhouse, showed the lowest levels of SMV incidence in the field of Suwon. Myeong-junamulkong, Ilpumgeomjeongkong, Soyangkong, Pungsannamulkong, Sodamkong, Jangmikong, Geomjeong-kong2, Pureunkong, Sinpaldalkong2, Duyoukong, and Geumgangkong were fairly resistant to SMV. And SMV incidence of Taekwangkong, Saealkong and Baegunkong was over 45% with symptom of bud necrosis. And soybeans, highly resistant to SMV in the field and the greenhouse, were mainly derived from Jangyeobkong and Hwang-keumkong resistant to G1-G7.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1262-1270
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• 2007

Some hot springs located in the west of Turkey were investigated with respect to the presence of thermophilic microorganisms. Based on phenotyping characteristics and 16S rRNA gene sequence analysis, 16 of the isolates belonged to the genus Geobacillus and grew optimally at about $60^{\circ}C$ on nutrient agar. 16S rRNA gene sequence analysis showed that these isolates resembled Geobacillus species by ${\ge}97%$, but SDS-PAGE profiles of these 16 isolates differ from some of the other species of the genus Geobacillus. However, it is also known that analysis of 16S rRNA gene sequences may be insufficient to distinguish between some species. It is proposed that recN sequence comparisons could accurately measure genome similarities for the Geobacillus genus. Based on recN sequence analysis, isolates 11, IT3, and 12 are strains of G stearothermophilus; isolate 14.3 is a strain of G thermodenitrificans; isolates 9.1, IT4.1, and 4.5 are uncertain and it is required to make further analysis. The presence of xylanase and arabinofuranosidase activities, and their optimum temperature and pH were also investigated. These results showed that 7 of the strains have both xylanase and arabinofuranosidase activities, 4 of them has only xylanase, and the remaning 5 strains have neither of these activities. The isolates 9.1, 7.1, and 3.3 have the highest temperature optima ($80^{\circ}C$), and 7.2, 9.1, AO4, 9.2, and AO17 have the highest pH optima (pH 8) of xylanase. Isolates 7.2, AO4, AC15, and 12 have optimum arabinofuranosidase activities at $75^{\circ}C$, and only isolate AC15 has the lowest pH of 5.5.

• KSBB Journal
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• v.19 no.4
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• pp.250-256
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• 2004

In this work we have cultivated several B. cereus strains in a complex LB medium in order to study the production of phospholipase C (PLC), and among them B. cereus 318 showed the highest productivity of PLC. Some components, i.e., 5 g/L glucose, 5 g/L yeast extract, 5 g/L peptone, 0.5∼1.0 g/L K$_2$HPO$_4$, 0.02∼0.04 g/L ZnSO$_4$$.$7H$_2$O and 3 g/L NaHCO$_3$ were found to be optimal for the high production of PLC by B. cereus 318. Optimal culture temperature and pH were found to be 30$^{\circ}C$ and pH 7.5 for the PLC production, respectively. Optimum reaction temperature and pH of the PLC produced by B. cereus 11 and 318 were 45$^{\circ}C$ and pH 4.0, while they were 50$^{\circ}C$ and pH 7.0 for the PLC by B. cereus 559. The PLC produced by B. cereus was activated by Mn$\^$2+/, Co$\^$2+/ and dimethyl sulfoxide (DMSO), but its activity was inhibited by Cu$\^$2+/ and partially by glycerol, isopropanol and sodium dodecyl sulfate (SDS).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.395-402
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• 2001

A fusant FG-21 was selected on the basis of higher ${\gamma}-GTP$ activity following fusion process between SM-2 and SM-10 of Bacillus subtilis mutants. ${\gamma}-GTP$ activity of the mutant FG-21 was increased up to 612 U/mL when grown for 36 hr at $37^{\circ}C$ in culture media containing 1% glycerol 1% glycerol, 1% peptone, 0.1% citric acid, 5 mM $K_2HPO_4$, 1 mM $FeCl_3$, 1 mM $MgCl_2$, 1 mM $NH_4Cl$, pH 7.0. In fusnat FG-21, the ratio of protein to total sugar contents for biopolymer A was 38 to 59. for biopolymer B from parental strains it was 19 to 78. Fructose contents determined by HPLC were $573.7\;\mu\textrm{g}/mg\;and\;764.4\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. And glutamic acid content were $163.7\;\mu\textrm{g}/mg\;and\;94.6\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. In fusant FG-21, the ratio of fructose to glutamic acid contents for biopolymer A was 78 to 22. For biopolymer B from parental strains it was 89 to 11.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.285-292
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• 2018

In this study, for the purpose of decomposing food waste, the strain was screened from traditional fermented food and soils. The enzyme activity (protease, amylase, cellulase, lipase) experiment was carried out using the paper disc method in 212 strains isolated from 5% NaCl media. Among them, only the strains having enzyme activity of more than 2 (soil) or more than 4 (traditional fermented food) with the halozone of enzyme activity of 15 mm or more were selected first, and microorganism identification through 16S rRNA sequencing was performed. Finally, were identified such as Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus siamensis, Bacillus licheniformis, Bacillus aquimaris, Bacillus megaterium, Bacillus koreensis, Bacillus stratoshericus, Bacillus aryabhattai, Bacillus safensis, Marinobacter hydrocarbonoclasticus. 11 species of mixed strains were confirmed that the culture time was 24 hours, the incubation temperature was $30^{\circ}C$ and the optimum pH was 7.0. In order to confirm the degree of decomposition of standard food wastes (100 g) by treating 11 kinds of mixed strains (25%), solid content of more than $2000{\mu}m$ was determined to be 103 g for the sterilized water group and 18 g for the mixed strains group. And the rest was decomposed to a size of less than $2000{\mu}m$.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.556-562
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• 1989

The bioconversion of mandarin orange peel press liquor to single cell protein (SCP) by two yeast strains, F-60, and C-7, which were isolated from mandarin orange peel was carried out and compared with that of using Candida utilis IFO 0598. Experiments were directed toward the high yield of biomass and high protein in cultures of the strains mentioned above. Candida utilis IFO 0598, F-60 and C-7 strains were cultivated at 3$0^{\circ}C$, pH 5.2 for 3 days in shaking flasks. The effects of some nutrients on cell growth were studied. Cell mass and protein content per cell mass were increased by addition of urea 1%, KH$_2$PO$_4$ 0.1% and MgSO$_4$ㆍ7$H_2O$ 0.05%, When the F-60 strain cultured under the optimal conditions, cell mass, growth yield and protein content were 41.2g/l, 53.9%, 59.7%, respectively. Cell mass was also increased up to 15% by modifying the fermentation condition on the bench type 20l jar fermentor. Crude fat content (10.3%) of dried C-7 cell was higher than those of C. utilis and F-60, 4.9% and 5.6% respectively. Total protein content of the F-60 strain was 59.7% per dry weight. And we compared their amino acid compositions with that of FAO provisional pattern. In the case of the F-60 strains, amino acid contents such as lysine, leucine and isoleucine were much higher than those of methionine, cystine and tryptophan.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.405-410
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• 1995

In order to screen dextranase with high dextranolytic activity from microbial origins, dextranase producing fungal isolates were isolated from soil of the Taeion area. 197 strains with dextranolytic activities were isolated, out of which 3 strains with high dextranolytic activities were selected in the first screening. A strain (GR-98) with a best dextranolytic activity was selected in the second screening. The strain was identified to be similiar Aspergillus ustus by the morphological and cultural characteristics. The optimum culture temperature and initial pH for the dextranase production of the strain was 30$\circ$C and 7.0, respectively. The optimum culture medium was composed of 2% dextran, 0.3% KNO$_{3}$, 0.05% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$-7H$_{2}$O, 0.05% KC1, and 2.5 $\mu$g/ml pyridoxamine, and the enzyme production was maximum when the strain was subcultured at 30$\circ$C for 7 days.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.47-54
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• 1980

Exoenzymes, protease(P) and elastase(E) produced by Pseudomonas aeruginosa are reported to have close relationship with pathogenicity of Pseudomonas aeruginosa. Productibility of exoenzymes P and E were studied and compared in environmental isolates from hospital environments and clinical isolates from various clinical specimens, also, the relationship between their enzyme production and serotype were reviewed. 1. Clinical isolates were typed into nine serotypes A, B, C, D, E, F, G, H and I. Serotype E had the highest incidence of 24%, followed by B with 16.8%, G, 15.1% and C, 9.3%. 2. Environmental isolates were, typed as serotype B, C, E, F, G, H, I, K and M. Serotype I had the highest incidence of 26.6%, followed by C, F and M each incidence of 14.3%. 3. In the typing of the above two groups, serotypes A and D were found only in the clinical isolates and serotypes K, and M were found only in the environmental isolates. Serotypes J and L were found in neither clinical isolates nor environmental isolates. 4. In the distribution of serotypes from various clinical specimens, serotype G among isolates from pus showed incidence of 20.4%, and serotypes E and B were 19.5% separately. Serotype E had incidence of 22.6% and 20.0% in urine and sputa respectively, showing a high rate compared to the other serotypes. 5. The incidence of strains producing both exoenzymes P and E was 77.8% in the preserved strains of clinical isolates and 76.2% in the environmental isolates. There were no significant difference between the two groups. 6. Serotypes A and H, which are preserved strains from clinical isolates showed productibility of both exoenzymes P and E, the other serotypes showed productibility of various combination of exoenzymes. Among the environmental isoaltes, production of both exoenzymes P and E were seen in serotypes E, F, G, H, I and K and no serotype produced only P or E. 7. In ability to produce exoenzymes of isolates from sources of various clinical specimens, strains producing both exoenzymes P and E were found most frequently in pus with incidence rate of 82.0%, followed by 80.0% in sputum and urine. 8. Almost all the fresh strains of clinical isolates were producers of both exoenzymes P and E.