• Korean Journal of Environmental Agriculture
• /
• v.34 no.2
• /
• pp.91-97
• /
• 2015

BACKGROUND: Earthworms are essential detritus feeders that play a vital role in the process of decomposition of organic matter and soil metabolism. The complex process of partial breakdown of organic matter and mixing with mucous and gut microbial flora in the form of earthworm cast results in the reduction of the toxicity. This study focused on the change of cast amount and pollutant contents before and after the eating of the organic waste and upland soil with the two species of earthworm. METHODS AND RESULTS: The two species of earthworms were compared to the cast production. In the upland soil material, the daily amount of worm's cast was 1.42 g in E. andrei and 0.40 g in A. agrestis. In the organic waste material, the cast of E. andrei was 0.78~0.83 g and the cast of A. agrestis. have not been collected because all earthworms died after the treatment. The heavy metals treated in the upland soil were evaluated the impact of the worm excretion. With the E. andrei, the cast production was decreased 0.1~0.8 times in zinc, 0.2~0.5 times in copper, and 0.1~0.7 times in cadmium compared to the control treatment according to the levels of concentration. With A. agrestis, the cast amount was decreased 0.3~1.1 times in zinc, 0.2~0.3 times in copper, and 0.1~2.1 times in cadmium, respectively. The changes of pollutant contents before and after the eating of the organic wastes with E. andrei were studied. In the treatment of the Alcohol Fermentation Processing Sludge and the Fruit Juice Processing Sludge, heavy metal content of the cast was increased 0.7~53.3% compared to the sludge materials. PAHs contents were decreased 50.1% in the cast of the Alcohol Fermentation Processing Sludge and 36.6% in the cast of the Fruit Juice Processing Sludge, respectively. CONCLUSION: In conclusion, although the A. agrestis was bigger than E. andrei in size and weight, the cast amount of A. agrestis was small. The two species of earthworm was less excretion with high concentration of heavy metals. While the heavy metals such as zinc, copper, and cadmium were considerably accumulated in the cast, the total compounds, PAHs were fairly decomposed. There results would provide us for restoring contaminated soil and cleaning organic wastes.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.2
• /
• pp.277-283
• /
• 2016

To improve the microbiological safety of wild vegetables after harvest, Aster scaber and Cirsium setidens Nakai were treated with combinations of 50 ppm aqueous chlorine dioxide ($ClO_2$)/0.5% citric acid or fumaric acid, and 50 ppm $ClO_2$/0.5% fumaric acid/blanching at $90^{\circ}C$ for 2 min. Combined treatment of 50 ppm $ClO_2$ and 0.5% citric acid reduced populations of total aerobic bacteria, yeast, and molds in Aster scaber and Cirsium setidens Nakai by 2.80~3.64 and 2.02~2.67 log CFU/g, respectively, compared to those of the control. Combined treatment of 50 ppm $ClO_2$ and 0.5% fumaric acid reduced total aerobic bacteria, yeast and molds populations by 3.62~3.82 and 2.47~3.02 log CFU/g, respectively. Based on the results, combined treatment of $ClO_2$ and fumaric acid was more effective in controlling microorganisms in the wild vegetables than either $ClO_2$ or citric acid. In addition, combined treatment of $ClO_2$/fumaric acid/blanching reduced the populations of total aerobic bacteria by 4.59~5.12 log CFU/g, and populations of yeast and molds were not detected by treatment. These results suggest that combined treatment of $ClO_2$/fumaric acid/blanching is the most effective method for improving microbiological safety of wild vegetables after harvest.

• Food Science and Preservation
• /
• v.9 no.3
• /
• pp.271-276
• /
• 2002

To develop a wrapping film, which suppresses the microbial decay through the storage and prolongs the selflife of fruits and vegetables, the antimicrobial packaging films were prepared and applied to the preservation of strtwberries and cucumbers. Low density polyethylene(LDPE) film of 50㎛ thickness was faricated with 1% of Scutellariae baicalensis extract. The LDPE film impregnated with Scutellariae baicalensis extract showed antimicrobial activity on the disk test against Bacillus cereus, Escherchia coli and Fusarium sp.. The antimicrobial film changed the color and light transmittance, but did not affect heat shrinkage, mechanical tensile strength and wattability. Strawberries and cucumbers were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped strawberries and cucumbers were stored for 21 days at 5$\^{C}$ and for 40 days at l0$\^{C}$, respectively. For the packaged strawberries and cucumbers at 5$\^{C}$ and 10$\^{C}$, the LDPE film impregnated with Scutellariae baicalensis extract showed the reduced growth of total aerobic bacteria, molds and yeasts and did not give any negative effect on other quality attributes during storage in comparison with conttrol film without any additive.

• Economic and Environmental Geology
• /
• v.45 no.2
• /
• pp.105-119
• /
• 2012

Indigenous bacteria isolated from contaminated sites play important roles to remediate contaminated groundwater. Chromium has the most stable oxidation states. Cr(VI) is toxic, carcinogenic, and mobile, but Cr(III) is less toxic and immobile. In this study, indigenous microorganism (MMPH-0) was enriched from Cr(VI) contaminated groundwater, and identified by 16S rRNA gene analysis. Using MMPH-0, the effect of stimulating with e-donors (glucose, lactate, acetate, and no e-donor control), respiration conditions, biomass, tolerance, and geochemical changes on Cr(VI) reduction were investigated in batch experiments for 4 weeks. The changes of Cr(VI) concentration and geochemical conditions were monitored using UV-vis-spectrophotometer and Eh-pH meter. And the morphological and chemical characteristics of MMPH-0 and precipitates in the effluents were characterized by TEM-EDS and SEM-EDS analyses. MMPH-0 (Enterobacter aerogenes) was able to tolerate up to 2000 mg/L Cr(VI) and reduce Cr(VI) under aerobic and anaerobic conditions. MMPH-0 performed faster and higher efficiency of Cr(VI) reduction with electron donors (over 70% after 1 week with e-donor, 10-20% after 4 weeks without e-donor). The changes of Eh-pH in effluents showing the tendency from oxidizing to reducing condition and a bit of acidic change in pH due to microbial oxidation of organic matters donating electrons and protons suggested the roles of MMPH-0 on Cr(VI) in the contaminated water catalyzing to transit geochemical stable zone for more stable $Cr(OH)_3$ or Cr(III) precipitates. TEM/SEM-EDS analyses of MMPH-0 and precipitates indicate direct and indirect Cr(VI) reduction: extracellular polymers capturing Cr component outside cells. These results suggested diverse indigenous bacteria and their biogeochemical reactions might enhance more effective and feasible remediation technology of redox sensitive heavy metals in metal-contaminated in groundwater.

• Journal of Life Science
• /
• v.19 no.2
• /
• pp.277-283
• /
• 2009

Biogenic amines are generally formed through the decarboxylation of specific free amino acids by exogenous decarboxylases released by microbial species associated with the fish products and fermented feeds. This study was conducted to investigate the properties of e tuna waste regarding the control of degradation of biogenic amines (histamine, tyramine, tryptamine, putrescine, and cadaverine) that might be related with the anti-nutritional factor of the tuna waste that is used for manufacturing domestic fish meal. The values of pH and the salt content were 6.51, 3.35% in tuna waste and 5.58 and 5.83% in tuna fish meal, respectively. The strains and dominant bacteria tested in the tuna waste sample were 9.20, 9.29, 5.67, 7.82 and 7.58 log CFU/g of total bacteria, aerobic plate count (APC), total coliform (TC), Lactobacillus spp. and Bacillus spp., respectively. The main histamine forming-bacteria (HFB) in tuna waste were detected by silica gel thin-layer chromatography (TLC) and 7 histamine-forming bacterial species were isolated among microbes grown in selective medium. The histamine concentration was determined by detection of fluorescence of ο-phthaldialdehyde (OPA) derivatives using HPLC and the date were used to reconfirm the identities of the amine-producing bacteria. The 15 histamine- forming bacteria strains grown in trypicase soy broth (TSB) supplemented with 1% L-histidine (TSBH) were identified as Lactococcus(L.) lactis subsp. lactis, Klebsiella pneummonlae, L. garvieae 36, Vibrio olivaceus, Hafnia alvei and L. garvieae which were main dominant amine - producing strains, and Morganella morganii identified by 16S ribosomal RNA (rRNA) sequencing with PCR amplification. A Phylogenetic tree generated from the 16S rRNA sequencing data showed different phyletic lines that could be readily classified as biogenic amine forming gram-positive and negative bacteria.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.22 no.3
• /
• pp.143-154
• /
• 2016

The purpose of this study was investigated the quality changes before and after harvesting, storage and, processing of onion. Experiments were carried out to compare the effect on the characteristics of the postharvest from preharvest factors using onion. This experiment had identified the characteristics of harvested onions after cultivating with several preharvest factors such as the light and water conditions. These tests were conducted in an onion growth in the field, storage, and processing of fresh-cut during a laboratory periods of 2 years. In first year, onion cultivars ('Kars' and 'Pop') were produced under stable or unstable environment conditions, these onions were stored at low temperature(0?). Measurement was evaluated by the growth amount after harvesting, and the fresh weight loss and respiration rate during storage. According to different culture conditions and storage temperatures, it was investigated the properties of the fresh-cut onion. Growth of onion was varied depending on the cultivars and culture conditions. The amount of growth on 'Kars' and 'Pop' onions were decreased by excessive soil water conditions with shading. These influences were found the morphological differences resulting for the cell tissue of onion being rough and large. Onion cultivated in excessive soil water with shading affected the degree of its respiration rate and fresh weight loss during storage. Ones in excessive soil water with shading were higher than the control in fresh weight loss and respiration rate, respectively. However fresh-cut onion could not investigated to clarify the difference due to effects of cultivation condition and storage temperature on some measure items such as electrolyte leakage and microbial number change. There was a change of only electrolyte leakage depending on the storage temperature, rather than cultivated conditions before harvesting factor. The results showed that the onion grown on in the good environment was represented to a good quality produce even after harvesting.

• Korean Journal of Soil Science and Fertilizer
• /
• v.26 no.4
• /
• pp.271-277
• /
• 1993

An antagonistic bacteria was isolated from rhiaosphere of pepper and corn and identified as Bacillus (B.) subtilis. These B. subtilis B-5 was transformed and marked with the plasmid pCPP4 which possess neomycine resistan. gene. The marked stranins showed growth inhibition to Rhizoctonia (R.) solani, Fusarium (F.) solani, and F. oxysporum in vitro, and were used in studying growth promoting effects on sesame and cabbage. All the identified strains utilize glucose, sucrose, fructose, lactose, mannitol and sorbitol as carbon source, but not rhamnose, and the marked strains also showed characteristics similar to wild-type strains. Germination rate of chinese cabbage and sesame seeds was increased by about 10% or more in the plot to which these strains were inoculated and the effect was higher in soil than in petri dish. The early growth promoting effects of these strains appeared higher, as compared with control plot, in the plots to which B. subtilis B-5 and pathogenic fungi was inoculated together. When the marked strains, B. subtilis B-5NEOr, were inoculated in the rhizosphere of chinese cabbage and sesame with $1.1{\times}10^8CFU/g$ dry soil, the number of inoculated strain was decreased slowly to the level of $10^5{\sim}10^6CFU/g$ dry soil after 4 weeks and the number of Pseudomonas spp. maintanied the level of $10^5CFU/g$ dry soil throught total period, but the number of fungi was decreased rapidly from the early level of $10^8CFU/g$ dry soil to $10^3CFU/g$ dry soil after 4 weeks.

• The Korean Journal of Mycology
• /
• v.32 no.1
• /
• pp.31-38
• /
• 2004

An endophytic bacterial strain EB215 that was isolated from cucumber (Cucumis sativus) roots displayed a potent in vivo antifungal activity against Colletotrichum species. The strain was identified as Burkholderia cepacia based on its physiological and biochemical characteristics, and 16S rDNA gene sequence. Optimal medium and incubation period for the production of antifungal substances by B. cepacia EB215 were nutrient broth (NB) and 3 days, respectively. An antifungal substance was isolated from the NB cultures of B. cepacia EB215 strain by centrifugation, n-hexane partitioning, silica gel column chromatography, preparative TLC, and in vitro bioassay. Its chemical structure was determined to be pyrrolnitrin by mass and NMR spectral analyses. Pyrrolnitrin showed potent disease control efficacy of more than 90% against pepper anthracnose (Colletotrichum coccodes), cucumber anthracnose (Colletotrichum orbiculare), rice blast (Magnaporthe grisea) and rice sheath blight (Corticium sasaki) even at a low concentration of $11.1\;{\mu}g/ml$. In addition, it effectively controlled the development of tomato gray mold (Botrytis cinerea) and wheat leaf rust (Puccinia recondita) at concentrations over $33.3\;{\mu}g/ml$. However, it had no antifungal activity against Phytophthora infestans on tomato plants. Further studies on the development of microbial fungicide using B. cepacia EB215 are in progress.

• Journal of Soil and Groundwater Environment
• /
• v.8 no.4
• /
• pp.27-35
• /
• 2003

The study site located in an industrial complex has a Precambrian age gneiss as a bedrock. The poorly-developed, disturbed soils in the study site have loamy-textured surface soil (1 to 2 m) and gravelly sand alluvium subsurface (2 to 6 m) on the top of weathered gneiss bedrock. The depth of the groundwater table was about 3.5 m below ground surface and increased toward down-gradient of the site. The hydraulic conductivity of transmitted zone (gravelly coarse sand) was in the range of 5.0${\times}$10$\^$-2/∼1.85${\times}$10$\^$-1/ cm/sec. The fine sand layer was in the range of 1.5${\times}$10$\^$-3/ to 7.6${\times}$10$\^$-3/ cm/sec. and the reclaimed upper soil layer was less than 10$\^$-4/ cm/sec. Toluene, ethylbenzene, and xylene (TEX) was the major contaminant in the soil and groundwater. The average depth of the soil contamination was about 1.5 m in the gravelly sand alluvium layer. At the depth interval 2.4∼4.8 m, the highest contamination in the soil is located approximately 50 to 70 m from the suspected source areas. The concentration of TEX in the groundwater was highest in the suspected source area and a lesser concentration in the center and southwest parts of the site. The TEX distribution in the groundwater is associated with their distribution in the soil. Microbial isolation showed that Pseudomonas flurescence, Burkholderia cepacia, and Acinetobactor lwoffi were the dominant aerobic bacteria in the contaminated soils. The analytical results of the groundwater indicated that the concentrations of dissolved oxygen (DO), nitrate, and sulfate in the contaminated area were significantly lower than their concentrations in the none-contaminated control area. The results also indicated that groundwater at the contaminated area is under anaerobic condition and sulfate reduction is the predominant terminal electron accepting process. The total attenuation rate was 0.0017 day$\^$-1/ and the estimated first-order degradation rate constant (λ) was 0.0008 day$\^$-1/.

• Microbiology and Biotechnology Letters
• /
• v.33 no.1
• /
• pp.16-23
• /
• 2005

In order to develop a new microbial fungicide using endophytic bacteria for the control of anthracnoses occurring on various crops, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth medium, their antifungal activities were tested for in vivo antifungal activity against cucumber anthracnose caused by Colletotrichum orbiculare. As the results, liquid cultures of 28 strains showed potent antifungal activities more than $90\%$ against cucumber anthracnose. At 3-fold dilutions of liquid cultures, 18 strains inhibited the development of cucumber anthracnose of more than $70\%$. They were further tested for in vivo antifungal activity against red pepper anthracnose caused by C. coccodes and in vitro antifungal activity against C. acutatum, a fungal agent causing red pepper anthracnose. Among 18 strains, a bacterial strain EB215 isolated from cucumber roots displayed the most potent antifungal activity against Colletotrichum species. It was identified as Burkholderia cepacia based on its physiological and biochemical characteristics, Biolog test and 16S rDNA gene sequence. It also controlled effectively the development of rice blast (Magnaporthe grisea), rice sheath blight (Corticium sasaki), tomato gray mold (Botrytis cinerea), and tomato late blight (Phytophthora infestans). Studies on the characterization of antifungal substances produced by B. cepacia EB215 are in progress.