• Journal of Species Research
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• v.11 no.4
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• pp.287-295
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• 2022

Three oxytrichid ciliates, Oxytricha lithofera Foissner, 2016, Pleurotricha curdsi (Shi et al., 2002) Gupta et al., 2003 and Sterkiella tetracirrata Kumar et al., 2015, were isolated from soils and confirmed as new to South Korea. Oxytricha lithofera was identified based on lithosomes, cortical granules, 21-33 adoral zone membranelles, one left (14-21 cirri) and one right (15-18) marginal rows and 5 transverse cirri. Pleurotricha curdsi was identified based on the possession of 2 macronuclear nodules, 2-3 micronuclei, 46-53 adoral zone membranelles, 3 frontal cirri, 5 frontoventral cirri, 5-7 postoral ventral cirri, 2-3 right marginal rows and 5 transverse cirri. Sterkiella tetracirrata was identified with respect 4 macronuclear nodules, 3-6 micronuclei, 25-40 adoral zone membranelles, 3 frontal cirri, 3 postoral ventral cirri, 2 pretransverse cirri, one left (21-30 cirri) and one right (24-30) marginal row and 4 transverse cirri. On the basis of 18S rDNA sequence analyses, we describe the phylogenetic positions of the three species.

• KSBB Journal
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• v.24 no.1
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• pp.53-58
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• 2009

This study was focused on the investigation of the characteristics of TPH and BTEX removal in oil-contaminated sandy soil and fine soil with injection of microorganisms, nutrients, and surfactants. As the result of the experiments maintained moisture contents by 10${\sim}$20%, the TPH removal efficiency in oil-contaminated sandy soil was the highest in C-1 (microorganisms+nutrients), and the efficiency in C-2 (microorganisms+nutrients+surfactants) was higher than the efficiency in C-0(microorganisms). In 81 days, TPH removal efficiency in case of C-0, C-1 and C-2 showed 51%, 83%, 63% respectively. The results of D group with fine soil showed similar trends as C group, but the TPH removal efficiency of D group was lower than that of C group. Those of both C and D group were the highest in 1 group (microganisms+nutrients). The pH of fine soil was some lower than that of sandy soil or was similar to sandy soil. In 14 days, BTEX removal efficiency in case of C-0, C-1, C-2, D-0, D-1 and D-2 showed 99.8%, 99.4%, 96.0%, 99.5%, 99.2%, 96.3% respectively. Those of both C and D group were the highest in 0 group (microganisms).

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.501-507
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• 2022

PET (Polyethylene terephthalate), a representative plastic material, has useful physicochemical properties such as high durability and economic feasibility, and is used in various industrial fields such as bottles, fibers, and containers. Due to the recent increase in plastic usage including disposable products, eco-friendly strategy using microorganisms have drawn attention differentiated from conventional landfill and incineration methods. In this study, a soil-derived Streptomyces javensis Inha503 containing a PETase gene was selected and the ability to hydrolyze PU (Polyurethane) was confirmed through agar plate diffusion assay. This strain was cultured with PET for a month, and PET decomposition ability was also confirmed through a scanning electron microscope. Moreover, cloning and heterologous expression of S. javensis Inha503 PETase gene exhibited PET activity in the PETase non-containing S. coelicolor, confirming for the first time the presence of functional PETase gene in Streptomyces species.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.442-445
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• 2000

Amphiphilic polyurethane(APU) particle is a polymeric surfactant, and could increase the solubility of 2-methylnaphthalene significantly. 2-Methylnaphthalene was recovered by the precipitation of APU particles and was degraded by Acinetobacter sp. K2-2. APU particle was recovered and reused after treatment of triethylamine.

• KSBB Journal
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• v.14 no.4
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• pp.503-510
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• 1999

In order to analyze nutritional factors affecting in situ bioremediation of diesel degradation and cell viability were studied by varying nutritional conditions. In column experiments packed with diesel-contaminated soil, nitrogen was found to be the major limiting nutrient. When nitrogen was added to soil at four different levels of C : N (100 : 5, 100 : 10, 100 : 15, and 100 : 20 mg N/kg dry soil), the greatest simulation of microbial activity occurred at the lowest, rather than the highest nitrogen addition. However, no significant effects was observed when phosphorus and air were added. No matter how the incubation mode varied, less than 50% of the diesel was remained after 7 days of treatment, presumably because the residual hydrocarbons were adsorbed on soil particles, adsorption

• KSBB Journal
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• v.23 no.6
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• pp.479-483
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• 2008

The environmental contamination by organic pollutants is a widespread problem. The most widely distributed pollution can be attributed to oil contamination. Bioremediation, the use of microorganism or microbial processes to degrade environmental contaminant, is one of the new technologies. The objective of the present study is to study the degradation of JP-8 in soil by microorganism. The degradation of JP-8 was analysed by TPH using gas chromatography. Rhodococcus fascians isolated from the petroleum contaminated site was applied for the degradation of JP-8 in the soil column system. Air flow rate of 30 ml/min was sufficient to degrade JP-8 in the soil column as much as 70% of JP-8 in the soil column. The addition of nitrogen source resulted in the increase in JP-8 degradability to 75% of JP-8 and the C:N ratio for JP-8 degradation was 100:10.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.327-330
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• 2002

Two polyacrylamide degrading bacterial strains, No. 2 and No. 11, were isolated from soil, and identified as Bacillus sphaericus No.2 and Acinetobacter sp. No. 11, respectively. Both strains grew on medium containing polyacrylamide as sole carbon and nitrogen sources. B. sphaericus No. 2 and A. sp. No. 11 reduced by 16% and 19%of the initial polyacrylamide concentration, respectively. Optimal pH and temperature in growth of Acinetobacter sp. No. 11 were 8.0 and $37^{\circ}C$, respectively. After 14-day cultivation of A. sp. No. 11, the average molecular weight of polyacrylamide has been shifted from $2.3{\times}10^6\;to\;0.5{\time}106$.

• Textile Coloration and Finishing
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• v.21 no.5
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• pp.1-9
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• 2009

The feasibility of earthworm protease as a new cosmetic material for human hair care was investigated. The effectiveness of the earthworm protease treatment was assessed by thickness change of hairs, optical microscope examination, aminoacid analysis, surface morphology, angular resolution analysis through methylene blue staining method and tensile strength change. The protease treated hair became thinner and the soil on the surface removed in experimental groups unlike control group. Tensile strength decreased in experimental group in which the enzymes may decompose polypeptide bonds.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.212-215
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• 2000

Recombinant bioluminescent bacterial strains that use specific promoters fused to the bioluminescence genes (lux genes) have been applied in environmental monitoring. Advantages of using recombinant bioluminescent bacteria as blosensing cells include rapid responses, low costs, and improved reproducibility. In this study, a recombinant Escherichia coli, GC2, containing a lac::luxCDABE fusion immobilized with solid agar media and glass beads was used to estimate the effect of this soil flushing technique. This bacterium constitutively emits light under normal conditions (no toxic chemicals). When growth and metabolism of these bioluminescent bacteria is inhibited by their exposure to toxic chemicals, the bioluminescence (BL) is reduced. A biosurfactant, rhamnolipids, was used to extract phenanthrene from the soil after flushing.

• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.105-108
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• 1997

A search was undertaken to screen microorganisms that produce an enzyme capable of deacylating glutary1-7-amincephalosporanic acid to 7-aminocephalosporanic acid in soil samples. The screening was carried out by preparing enrichment cultures containing glutary-7ACA and cephalosporin C as selective carbon sources. A non-${\beta}$-lactam model compound,, glutary-p-nitroanilide, was synthesized as a substrate suitable for the rapid screening of microorganisms isolated from the enrichment cultures. Two isolates exhibiting acylase activity, designated BY7.4 and BY8.1, were identified as strains of Pseudomonas species. Pseudomonas BY8.1 showed higher acylase activity toward G1-7ACA than Pseudomonas BY7.4. Environmental conditions for the optimal acylase activity of Pseudomonas BY8.1 were shown to be pH9 and 30$^{\circ}C$.