• Clean Technology
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• v.16 no.2
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• pp.117-123
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• 2010

In this study, we propose two methods able to recover different type of gold from gold-cyanide solutions: biosorption and desorption process for mono-valent gold recovery and biosorption and incineration process for zero-valent gold recovery. The waste bacterial biomass of Corynebacterium glutamicum generated from amino acid fermentation industry was used as a biosorbent. The pH edge experiments indicated that the optimal pH range was pH 2 - 3. From isothermal experiment and its fitting with Langmuir equation, the maximum uptake capacity of Au(I) at pH 2.5 were determined to be 35.15 mg/g. Kinetic tests evidenced that the process is very fast so that biosorption equilibrium was completed within the 60 min. To recover Au(I), the gold ions were able to be successfully eluted from the Au-loaded biosorbent by changing the pH to pH 7 and the desorption efficiency was 91%. This indicates that the combined process of biosorption and desorption would be effective for the recovery of Au(I). In order to recover zero-valent gold, the Au-loaded biosorbents were incinerated. The content of zero-valent gold in the incineration ash was as high as 85%. Therefore, we claim on the basis of the results that two suggested combined processes could be useful to recover gold from cyanide solutions and chosen according to the type of gold to be recovered.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.214.2-214
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.280.1-280
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• 1997

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.281.1-281
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• 1997

No Abstract, See Full Text

• Economic and Environmental Geology
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• v.46 no.4
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• pp.345-350
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• 2013

In this study, the physicochemical properties of leachate and the bacteria existence in leachate using molecular biology methods for 4 animal carcass disposals on the disposal lapse time was analyzed. The result of leachate physicochemical analysis in the middle stage (been buried 20 months) showed higher EC, DO, $HCO_3{^-}$, TOC, T-N and $SO_4{^{2-}}$ concentration compared to the first stage data (been buried 5 months). For identification of leachate using 16S rRNA method, Lysinibacillus sphaericus, Bacillus pumilus, Pseudoclavibacter helvolus, Pseudochrobactrum saccharolyticum and Corynebacterium callunae in the first stage, Bacillus cereus, Lysinibacillus sphaericus, Bacillus circulans and Corynebacterium glutamicum in the middle stage was observed, while there were detections of pathogenicity bacteria such as B. cereus and L. sphaericus. This study improves our knowledge of the fate and transport in geologic media, treatment, risk analysis on the leachate from animal carcass disposal sites.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.677-680
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• 1992

The effects of pH, temperature and oxygen transfer rate(OTR) on L-Ieucine fermentation were investigated employing Corynebacterium glutamicum CH 1516 in 71 fermentor. The optimum pH, temperature and OTR were determined to be 7.0, $30^{\circ}C$ and 0.21 kmole $O_2$/$m^3{\cdot}hr$, respectively. For the values of OTR lower than 0.19 kmole $O_2$/$m^3{\cdot}hr$ a significant amount of lactic acid was accumulated, while the packed cell volume(PCV) was rapidly increased at higher OTR values above 0.23 kmole $O_2$/$m^3{\cdot}hr$ and glutamic acid was produced to some extent. Scale-up studies for L-Ieucine fermentation which was carried out in 12001 pilot scale fermentor reaffirmed the results of 71 fermentation. The optimum redox potential value for L-Ieucine production was found to be -150 to -170 mY.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.175-181
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• 1988

To produce L-lysine from cellulosic substrate, the intergeneric protoplast fusion between Cellulomonas flavigena and Corynebacterium glutamicum, Cellulomonas flavigena and Brevibacterium flavum was performed. The fusion frequencies were 1.9$\times$10$^{-6}$ to 2.1$\times$10$^{-6}$ for the regenerated protoplasts when two parental strains were treated with 30% of polyethyleneglycol (M.W.6000) containing 5 mM EDTA at 3$0^{\circ}C$ for 30 min. Two fusants, FCB3 and FCC 19 were finally selected by comparision of their genetic stability and L-lysine productivity. The properties of fusants-DNA con-tent, G＋C content and L-lysine productivity-were investigated. The DNA content of fusants was greater than those of the parental strain and their G＋C contents are equal to half of total G＋C con-tent of two parental strains. The fusants showed high productivity of L-lysine from carboxy methyl cellulose as substrate.

• Korean Journal of Organic Agriculture
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• v.7 no.1
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• pp.129-135
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• 1998

This study was conducted to clarify the plant growth promoting effects of the various rhizobacteria on the growth of hydroponically grown tomatoes in rockwool, perlite and cocopeat cultures. Strains in terms of $Azospirilham\;sp.(4.5{\times}10^7cells/g),\;Rhodopseudomonas\;sp.(5.8{\times}10^5cells/g),\;Pseudomonas\;sp.(6.1{\times}10^6cells/g$), fusant of $Bacillus\;sp.\;and\;Corynebacterium\;glutamicum(9.1{\times}10^5cells/g$) was bacterialized into the root zone of tomatoes before sowing. Overall growth of tomato plants was promoted by bacterialization of the various rhizobacteria. Strains which showed the highest plan growth promoting effects of hydroponically grown tomatoes was Azospirillum sp., and optimum cultural substrates for the plant growth promotion by rhizobactera were in the order of cocopeat > perlite = rockwool cultures.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.211-217
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• 2013

Corynebacterium glutamicum is one of the well-studied industrial strain that is used for the production of nucleotides and amino acids. Recently, it has also been studied as a possible producer of organic acids such as succinic acid, based on its ability to produce organic acids under an oxygen deprivation condition. In this study, we conducted the optimization of medium components for improved succinate production from C. glutamicum under an oxygen deprivation condition by Plackett-Burman design and applied a response surface methodology. A Plackett-Burman design for ten factors such as glucose, ammonium sulfate, magnesium sulfate, potassium phosphate ($K_2HPO_4$ and $KH_2PO_4$), iron sulfate, manganese sulfate, biotin, thiamine, and sodium bicarbonate was applied to evaluate the effects on succinate production. Glucose, ammonium sulfate, magnesium sulfate, and dipotassium phosphate were found to have significant influence on succinate production, and the optimal concentrations of these four factors were sequentially investigated by the response surface methodology using a Box-Behnken design. The optimal medium components obtained for achieving maximum concentration of succinic acid were as follows: glucose 10 g/l, magnesium sulfate 0.5 g/l, dipotassium phosphate ($K_2HPO_4$) 0.75 g/l, potassium dihydrogen phosphate ($KH_2PO_4$) 0.5 g/l, iron sulfate 6 mg/l, manganese sulfate 4.2 mg/l, biotin 0.2 mg/l, thiamine 0.2 mg/l, and sodium bicarbonate 100 mM. The parameters that differed from a normal BT medium were glucose changed from 40 g/l to 10 g/l, dipotassium phosphate ($K_2HPO_4$) 0.5 g/l changed to 0.75 g/l, and ammonium sulfate ($(NH_4)_2SO_4$) 7 g/l changed to 0 g/l. Under these conditions, the final succinic acid concentration was 16.3 mM, which is about 1.46 fold higher than the original medium (11.1 mM) at 24 h. This work showed the improvement of succinate production by a simple change of media components deduced from sequential optimization.

• YAKHAK HOEJI
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• v.40 no.2
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• pp.212-217
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• 1996

Streptomyces cattleya is a producer of carbapenem antibiotics, thienamycin and N-acetylthienamycin, which have potent and broad-spectrum antibacterial activities. We stud ied on strain improvement for antibiotic productivity of S. cattleya by transformation technique which employed S.cattleya protoplasts and chromosomal DNAs of glutamic acid producers: Corynebacterium glutamicum and Arthrobacter simplex. 150 Transformant strains were cultured and bioassayed using Bacillus subtilis and Staphylococcus aureus as test organisms. 8.7% of transformants tested showed 1.4~2.6 fold higher productivities than wild type which produced $1.61{\pm}0.67{\mu}g/ml$. The best transformant produced $8.36{\pm}2.84{\mu}g/ml$ carbapenems.