• Journal of Ecology and Environment
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• v.35 no.4
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• pp.279-289
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• 2012

This study conducted a comparative analysis of benthic macroinvertebrate communities in the Fosu and Benya lagoons in Ghana, based on the anthropogenic effect on the two lagoons. Salinity, oxygen, temperature, conductivity, turbidity and pH were measured, invertebrate richness and species densities were determined. The AZTI Marine Biotic Index (AMBI) and multivariate statistics were used to determine the different responses of fauna to pollution. The fauna were categorized into five ecological groups based on the degree of tolerance of the different species to pollution: disturbance-sensitive species; disturbance-indifferent species, disturbance-tolerant species, second-order opportunistic species; and first-order opportunistic species. The Fosu Lagoon supported more pollution tolerant species, whereas the Benya Lagoon had more species that were sensitive to organic enrichment under relatively unpolluted conditions. Chironomus sp., which is adapted to virtually anoxic conditions, was the most abundant in the Fosu Lagoon whereas Nemertea sp. was the most abundant in the Benya Lagoon. The numerical and relative abundance (%) of all 7 taxa in the Fosu Lagoon was 1,359 and 92.35%, respectively. The numerical and relative abundance (%) of all 34 taxa in the Benya Lagoon was 2,459 and 87.52%, respectively. Expectedly, the level of dissolved oxygen in the less saline Fosu Lagoon was higher than that in the more saline Benya Lagoon. The reduced photoperiod and photosynthetic activities of aquatic plants might account for this trend. There is a need to implement comprehensive monitoring and management initiatives for sustaining the ecological health of coastal lagoons in Ghana in order to support the many people that depend upon these ecosystems for their livelihood.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.243-249
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• 1995

In order to investigate the origin of sulfate in rain waters and to evaluate the feasibility of using sulfur isotope method as a tracer of atmospheric pollutants, the sulfur isotopic ratio of sulfate in rain waters collected in Chonju city from October 1994 to March 1995 was monitored and was compared with those of possible sources proposed by previous works. The pH of rain waters shows an intermediate acidic range from 4.45 to 6.88 and their daily variation appears to be well correlated with to the amount of precipitation. The sulfur isotopic ratios of sulfate in rain waters show a highly restricted range from 0.0 to + 1.8‰. The ${\delta}^{34}S$ values are similar to those of soil and pine tree surrounding Chonju city, but largely deviate from those of China. D-parameter($d={\delta}D-8{\delta}^{18}O$) of rain waters varies from 9.4 to 28.8. The values indicate that the rain waters in Chonju city are originated from the rainy front of China continent. All data obtained from this study suggested that sulfate in the rain waters collected in Chonju city was mainly derived from the sulfur dioxide gas emitted by the petroleum combustion. Therefore, sulfur isotopic study for the precipitation provided an excellent tool for environmental assessment in this region and for tracing the source of atmospheric pollutants.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1868-1873
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• 2006

A novel microorganism that could degrade high molecular weight gellan was screened and isolated from soil. On gellan plate, the microorganism grew well and completely liquefied the plate. The gellan-degrading microorganism was isolated by pure culture on glucose and nutrient agar medium afterwards. The 16S rDNA sequence analysis and biochemical tests using an API 50CHB/20E kit revealed that the strain belonged to Bacillus sp. The isolate, named as Bacillus sp. YJ-1, showed optimum gellan-degrading activity in 0.5% gellan medium at pH 7.5 and 37$^{\circ}C$. The activity was measured and evaluated by the thiobarbituric acid and thin-layer chromatography method. Mass spectrometry revealed that the major gellan.. depolymerized product was an unsaturated tetrasaccharide consisting of $\Delta$4,5-glucuronic acid-(1$\rightarrow$4 )-$\beta$-D-glucose-(1$\rightarrow$4)- $\alpha$-L-rhamnose-(1$\rightarrow$3)-$\beta$-D-glucose, which is a dehydrated repeating unit of gellan, thus the enzyme was identified as gellan lyase. When the gellan was present in the medium, the gellan-degrading activity was much higher than that in glucose-grown cells. These results indicate that in the presence of gellan, Bacillus sp. YJ-1 is able to metabolize the gellan by inducing gellan-degrading enzymes that can degrade gellan into small molecular weight oligosaccharides, and then the gellan. depolymerized products are taken up by the cells and utilized by intracellular enzymes.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.148-156
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• 2006

Potential hydrocarbon degrading bacteria were screened from the site artificially polluted with 20,000 ppm of diesel. Among the isolates, two strains, SJD2 and SJD4, showed higher activities to degrade diesel on the Bushnell-Hass broth medium containing 2% of diesel. 16S rDNA sequence analysis revealed that SJD2 and SJD4 were Bacillus fusifomis and B. cereus, respectively. Both strains were found to grow in a wide range of temperature between $20^{\circ}C-55^{\circ}C$, with the best at $30^{\circ}C-37^{\circ}C$. This is the first report, as far as we know, that B. fusifomis is capable of degrading diesel. We hope that a new isolate, B. fusifomis, will efficiently conduct bioremediation at the contaminated sites with petroleum hydrocarbons.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E1
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• pp.23-35
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• 2005

Size distribution of particulate water-soluble ion components was measured at Gosan, Korea using a micro-orifice uniform deposit impactor (MOUDI). Sulfate, ammonium, and nitrate showed peaks in three size ranges; Sulfate and ammonium were of dominant species measured in the fine mode ($D_{p} < 1.8 {\mu}m$). One peak was observed in the condensation mode ($0.218\sim0.532{\mu}m$), and the other peak was obtained in the droplet mode ($0.532\sim1.8{\mu}m$). Considering the fact that the equivalent ratios of ammonium to sulfate ranged from 0.5 to 1.0 in these size ranges, it is inferred that they formed sufficiently neutralized compounds such as ($NH_{4})_{2}SO_{4} and (NH_{4})_{3}H(SO_{4})_{2}$ during the long-range transport of anthropogenic pollutants. On the other hand, nitrate was distributed mainly in the coarse mode ($3.1\sim6.2{\mu}m$) combined with soil and sea salt. Two sets of MOUDI samples were collected in each season. One sample was collected when the concentrations of criteria air pollutants were relatively high, but the other represented relatively clean air quality. The concentrations of sulfate and ammonium particles in droplet mode were the highest in winter and the lowest in summer. When the air quality was bad, the increase of nitrate was observed in the condensation mode ($0.218\sim0.282{\mu}m$). It thus suggests that the nitrate particles were produced through gas phase reaction of nitric acid with ammonia. Chloride depletion was remarkably high in summer due to the high temperature and relative humidity.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.50-56
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• 2003

A freshwater bloom-forming cyanobacterium, Microcystis aeruginosa, and local soil isolate Scytonema sp. strain BT 23 were demonstrated to contain biotoxic secondary metabolites with pesticidal and mosquito larvicidal activities. A purified toxic constituent from M aeruginosa showed an absorption maximum at 230 nm and its toxicity symptoms, Rf value on TLC, and retention time observed ill an HPLC analysis were similar to those of the hepatotoxic heptapeptide microcystin-LR. The bioactive constituent of the Scytonema sp. was less polar in nature and exhibited two peaks at 240 and 285 m. When applied to two cruciffrous pests, Pieris brassicae and Plutella flostella, the crude extracts and toxic principles from the two cyanobacteria showed significant antifeedant activity in a no-choice bioassay, and at higher concenuations exhibited contact toxicity to the insect larvae. The purified toxin from M. aeruginosa was found to be more effective and produced 97.5 and $92.8\%$ larval mortality in the two pests, fo11owing 2 h of toxin treatment at a concentration of $25{\mu}g$ Per leaf disc (2.5 cm dia.). Meanwhile, similar treatment with the purified toxin from Sytonema sp. stain BT 23 only produced 73 and $78\%$ mortality in the two pests. The cyanobacterial constituents also showed significant activity against Culex and Anopheles larvae. The M. aeruginosa toxin ($20{\mu}g\;ml^-1$) caused 98.2 and $88.1\%$ mortality in the Culex and Anopheles larvae, respectively, while the purified toxin from the Sytonema sp. was less toxic and only produced a 96.3 and $91.2\%$ mortality, respectively, at a much higher concentration ($40{\mu}g\;ml^-1$). Accordingly, the current results point to certain hitherto unknown biological properties of cyanobacterial biotoxins.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.921-928
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• 2002

Microorganism producing extracellular CFTase was isolated from soil and designated as Bacillus polymyxa MGL21. The gene encoding the CFTase (cft) from B. polymyxa MGL21 was cloned and sequenced. The ORF of the cf gene was composed of 3,999 nucleotides, encoding a protein (1,333 amino acids) with a predicted molecular mass of 149,375 Da. Sequence analysis indicated that CFTase was divided into five distinct regions. CFTase contained three regions of repeat sequences at the N-terminus and C-terminus. The endo-inulinase region of homology (ERH) of CFTase was similar to that of Pseudomonas mucidolens endo-inulinase ($50\%$ identity, 259 amino acids). Furthermore, CFTase possessed a highly conserved core region, which is considered to be functional for the hydrolysis reaction of inulin. The cft gene was expressed in a His-tagged form in Escherichia coli cells, and the His-tagged CFTase was purified to homogeneity. The optimal temperature and pH for CFTase activity were found to be $50^{\circ}C$ and 9.0, respectively. The enzyme activity was completely inhibited by 10 mM $Ag^+\;and\;Cu^2+$. Thin-layer chromatography analyses indicated that CFTase catalyzed not only the cyclization reaction ut also disproportionation and hydrolysis reactions as well.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.94-100
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• 2006

To isolate a bacterium that produces plant growth promoting hormone, a total of 29 bacteria were obtained from the soil in Gyeongsan, Korea. Among these, 14 strains were selected by their positive reaction on Salkowski to produce auxin. All of these were then tested for their property to produce siderophore using CAS (chrome azurol S) blue agar, and one was chosen for its ability to produce both, auxin and siderophore. This strain, denoted, AHl8, showed 1.5 times higher adventitious root induction rates than controls, using mung-beans. The strain also showed efficient biocontrol properties towards Fusarium-wilt of tomatoes in artificial pot assays. The strain was identified as Bacillus subtilis by 16s rDNA comparison and Biolog analyses. Growth and media conditions for Bacillus subtilis AH1 8 to highly produce siderophore were also investigated.

• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.207-212
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• 1981

A strain of Penicillium sp. which produces considerable amount of $\beta$-galactosidase was selected from extracellular $\beta$-galactosidase-producing fungi isolated from soil. The enzyme was found to be very stable in neutral pH range. Maximum enzymatic activity was reached after 72 hr of incubation in a wheat bran medium at 3$0^{\circ}C$. Productivity of the enzyme appeared not to be affected by the addition of carbon sources to the medium but the activity of the enzyme was increased from 14% to 85% by the addition of various nitrogen sources. The enzyme extracted from the wheat-bran culture of the Penicillium sp. was purified to 5050-fold by ammonium sulfate fractionation, SP-Sephadex C-50 chromatography, Ultrogel AcA 44 filtration and hydroxyapatite chromatography. The purified $\beta$-galactosidase was homogeneous on ultracentrifugation and disc electrophoresis.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.319-324
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• 1991

Three strains able to efficiently produce ethanol from cellulosic hydrolysates were isolated from soil samples by enrichment culture in liquid saccharified wheat bran medium. The profiles of physiological and biochemical properties of two yeasts KM-09 and KM-402 and a bacterium Hg-225 were almost identical from those of Candida sp. and Klebsiella sp., respectively. Strains KM-09 and HG-225 used xylose and cellobiose as fermentable sugars, and HG-225 had a wide range of sugar utilization for ethanol fermentation. The optimal pH and temperature for growth of KM-09, KM-402 and HG-225 were 5.8, 5.6 and 6.8 and 32t, $30^{\circ}C$~ and $38^{\circ}C$, respectively. During the ethanol fermentation in saccharified wheat bran by the isolated strains, optimal temperature for ethanol production was more or less higher than those for growth, and addition of 0.2% (w/v) $MgSO_4$, into the medium enhanced ethanol productivity. Of the three strains ethanol content of KM-09 was the highest with about 2.3% (v/v), and ethanol production rate of HG-225 was faster than the others and maximum productivity was after 4 days. KM-09 (1.42% v/v) and HG-225 (1.05%, vlv) produced ethanol from 4% (wIv) xylose but growth rate was slower than on glucose. Otherwise KM-402 showed the highest ethanol productivity on glucose, but no ethanol was detected on xylose and cellobiose.