• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.151-158
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• 1997

For the production of potent chitinolytic enzyme from bacteria, screening was carried out. Of 100 samples from soil, fresh water and sea water collected from the Kyung-gi area, 7 strains of chitinolytic bacteria were isolated. Among them, Aeromonas hydrophila 5-3K showed the highest chitinolytic activity. Culture conditions of Aeromonas hydrophila for the production of chitinolytic enzyme were inverstigated and lytic enzyme was fractionated by the use of ammonium sulfate and Sephadex G-100. Maximum production of chitinolytic enzyme was obtained at pH 7.0 and 30$\circ$C with chitin concentration between 0.2% and 1.0%. Conditions for the enzyme production were optimized including fermentor cultivation. The chitinolytic system of Aeromonas hydrophila 5-3K was composed of two enzymes, chitinase and chitobiase.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.36-39
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• 2001

The secondary effects of pencycuron on cell membrane of Rhizoctonia solani AG4 were investigated by the observation of giant protoplast formation and lipid peroxidation. Compared to protoplasts of R. solani R-C (sensitive strain) and Rh-131 (non-sensitive strain) increased in their size by 2.0-3.5 times 12 h after incubation in potato-dextrose broth containing novozyme (7 mg/$m\ell$) and $\beta$-glucuronidase ($60\mu\textrm{g}/$\textrm{ml}) with 0.6 M mannitol (pH 5.2). The increase of protoplast size in R-C was slightly inhibited from $13.8\textrm{mg}/\textrm{ml}$ without pencycuron to 10.3 ${\mu}{\textrm}{m}$ with 1.0$\mu\textrm{g}$/$m\ell$ of pencycuron. However, the size of giant protoplast of Rh-131 was not affected by the pencycuron treatment. Both strains R-C and Rh-131 did not exhibit the lipid peroxidation 12 h after the application of 1.0 $\mu\textrm{g}$/$m\ell$ pencycuron. The remarkable peroxidation of membrane lipid was observed only in R-C 24 h after pencycuron application, but not in Rh-131. Althought the inhibition of giant protoplast formation and the membrane lipid peroxidation were observed only in the sensitive strain R-C by pencycuron, it is difficult to conclude that these are the primary mechanism of pencycuron. The mild activity of pencycuron on the inhibition of giant protoplast formation and late membrane lipid peroxidation in the fungicide-sensitive strain did not noincid with the dramatic activity of pencycuron in R. solani. Therefore, our results suggest that inhibition of giant protoplast formation and membrane lipid peroxidation is the secondary effect of pencycuron.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.3
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• pp.288-293
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• 2004

This study was carried out to determine the antimutagenic and anticancer effects of fermented soybean using Ames test and cytotoxicity, respectively. The ethyl acetate fraction (200 g/plate) of fermented soybean in the Salmonella typhimurium TA100 strain showed 86.6% of inhibition rate against the mutagenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG). In addition, the suppression of ethyl acetate fraction with same concentration of fermented soybean in the Salmonella typhimurium TA98 and TAI00 strains showed 82.4% and 90.8% inhibition against 3-amino-l,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-l), respectively. The cytotoxicity effects of fermented soybean against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL ethyl acetate fraction of fermented soybean showed strong cytotoxicities of 71.6%, 91.5% and 80.7% against A549, AGS and MCF-7, respectively.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.73-78
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• 2002

Bacillus polyfermenticus SCD, which is commonly called as Bisroot strain, is being used for functional foods through the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine in both humans and animals. The cells of B. polyfermenticus SCD were treated for 24 h in artifical bile after incubation for 2 h in artificial gastric juice and final number of the strain was reached to around $3.3{times}10^7\;CFU/mL$. In test of API ZYM kit, ${\beta}-glucuronidase$ or ${\beta}-glucosidase$ was not produced by B. polyfermenticus SCD. B. polyfermenticus SCD was resistant to antibiotics, such as nisin, streptomycin, tetracycline, and rifamycin. B. polyfermenticus SCD was also affected by alcohol concentration up to 4%, but more than 8%, their growth was not affected significantly. Finally, B. polyfermenticus SCD was shown to inhibit the growth of Listeria monocytogenes ATCC 19111 completely within 24 h of incubation, which indicated its bactericidal nature.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.44-47
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• 1998

Maximum cellulase production was sought by comparing the activities of the cellulases produced by different Trichoderma reesei strains and Aspergillus niger. Trichoderma reesei Rut-C30 showed higher cellulase activity than other Trichoderma reesei stains and Aspergillus niger that was isolated from soil. By optimizing the cultivation conditions during shake flask culture, higher cellulase production could be achieved. The FP(filter paper) activity of 3.7U/ml and CMCase (Carboxymethylcellulase) activity of 60U/ml were obtained from shake flask culture. When it was grown in 2.5L fermentor, where pH and DO levels are controlled, the enzyme activities were 133.35U/ml (CMCase) and 11.67U/ml(FP), respectively. Ammonium sulfate precipitation method was used to recover enzymes from fermentation broth. The dried cellulase powder showed 3074.9U/g of CMCase activity and 166.7U/g of FP activity with 83.5% CMCase recovery.

• Tuberculosis and Respiratory Diseases
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• v.56 no.3
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• pp.261-268
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• 2004

Background : The resurgence of tuberculosis and outbreaks of multidrug resistant (MDR) tuberculosis have increased the emphasis for the development of new susceptibility testing of the Mycobacterium tuberculosis for the effective treatment and control of the disease. Conventional drug susceptibility testings, such as those using egg-based or agar-based media have some limits, such as the time required and difficulties in determining critical inhibitory concentrations, but these are still being used in many diagnostic laboratories because of no better lternatives, considering cost and accuracy. To overcome these limits, a rapid and simple method for new susceptibility testing, using live and dead assays, was applied for a bacterial cell viability assay to distinguish dead from live bacterial cells based on two-color fluorescence. Materials and Methods Strains : Forty strains were used in this study, 20 susceptible to all antituberculosis drugs and the other 20 resistant to the four first line antituberculosis drugs isoniazid, rifampicin, streptomycin and ethambutol. Antibiotics : The four antibiotics were dissolved in 7H9 broth to make the following solutions: $0.1{\mu}g\;isoniazid(INH)/m{\ell}$, $0.4{\mu}g\;rifampicin(RMP)/m{\ell}$, $4.0{\mu}g\;streptomycin(SM)/m{\ell}$ and $4.0{\mu}g\;ethambutol(EMB)/m{\ell}$. Results : Live and dead Mycobacterium tuberculosis cells fluoresced green and red with the acridin (Syto 9) and propidium treatments, respectively. These results are very well accorded with conventional drug susceptibility testing by proportional method on Lowensen-Jensen media (L-J) containing 4 drugs (INH, RMP, EMB and SM), showing a 93.7 % accordance rate in susceptible strains and 95% in resistant strains. Conclusion : The results of the drug susceptibility testing using the live and dead bacterial cell assay showed high accordance rates compared with the conventional proportion method on L-J. This finding suggests that the live and dead bacterial cell assay can be used as an alternative to conventional drug susceptibility testing for M. tuberculosis strains.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.1004-1014
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• 2013

Six nonpathogenic fungal strains isolated from alkaline soils of Buenos Aires Province, Argentina (Acremonium murorum, Aspergillus sidowii, Cladosporium cladosporoides, Neurospora tetrasperma, Purpureocillium lilacinum (formerly Paecilomyces lilacinus), and Westerdikella dispersa) were tested for their ability to produce keratinolytic enzymes. Strains were grown on feather meal agar as well as in solid-state and submerged cultures, using a basal mineral medium and "hair waste" as sole sources of carbon and nitrogen. All the tested fungi grew on feather meal agar, but only three of them were capable of hydrolyzing keratin, producing clear zones. Among these strains, P. lilacinum produced the highest proteolytic and keratinolytic activities, both in solid-state and submerged fermentations. The medium composition and culture conditions for the keratinases production by P. lilacinum were optimized. Addition of glucose (5 g/l) and yeast extract (2.23 g/l) to the basal hair medium increased keratinases production. The optimum temperature and initial pH for the enzyme production were $28^{\circ}C$ and 6.0, respectively. A beneficial effect was observed when the original concentration of four metal ions, present in the basal mineral medium, was reduced up to 1:10. The maximum yield of the enzyme was 15.96 $U_c/ml$ in the optimal hair medium; this value was about 6.5-fold higher than the yield in the basal hair medium. These results suggest that keratinases from P. lilacinum can be useful for biotechnological purposes such as biodegradation (or bioconversion) of hair waste, leading to a reduction of the environmental pollution caused by leather technology with the concomitant production of proteolytic enzymes and protein hydrolyzates.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.277-283
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• 1977

1) Higher yield of red color was observed by the isolated strain (Monascus D-7) than the type cultures in steamed rice medium. 2) In a case of Monascus purbigerus IAM 8004, best yield of color was obtained at Lin's submerged culture medium containing 1% wheat bran, 2% starch and 3% corn meal instead of rice powder as carbon source. However, in a case of isolated strain (M. D-7), good result was shown at 1% rice bran and 2% starch as a source of carbon in Lin's medium. 3) Good yields were obtained from both strains in Nishikawa's medium which was added with 3% defatted soybean flour. 4) There were no significant differences in pigment extractability among solvents. Extracted pigment was stable in wide range of pH and heat, whereas relatively unstable in sunlight. 5) Toxicological study of extracted pigment determined $LD_{50}$ at 0.2539g/20g, when injected in mouse. When injected in to mouse in 25% ethanol solution: considering the toxicity of ethanol, the toxicity of pigment itself is believed to be none.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.478-483
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• 2004

The optimum fermentation conditions of Propionibacterium acidipropionici were determined for the maximum production of organic acids. Three strains of P. acidipropionici, ATCC 25562, 4875, 4965 were selected to test the productivity of organic acids in the batch fermentation. Nutrients and environmental conditions on cell growth were defined by series of experiments, and the optimum amounts of peptone, yeast extract were determined to be $1.5\%$ (w/v), $0.75\%$ (w/v), respectively. The yields and productivity were highest at pH 6 among the ranges of $5.0{\sim}7.5$, and ATCC 4965 was determined to be the best strain compared to the others by getting total productivity of 0.29 g total acids/L/h. Approximately $1.60{\sim}2.34$ moles of propionic acid and $0.74{\sim}1.05$ moles of acetic acid were produced from 1.5 moles of glucose.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.322-328
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• 2000

To screen agent for the treat-ment of Alzhimers Disease several strains of bacteria producing acetylcholinesterase inhibitor ware isolated from soil. Strain 960903 showed strong acetylcholinesteras inhibitory activity and low butyrylcholinesterse inhibitory activity. The strain 960903 was identified as Pseudomonas sp. Acetylcholinesterase inhibitor ws highly achieved in fermentation medium containing soluble starch 3.0%, glycerol 1.0%, pharmamedia 0.5%, KCI 0.3%, $CaCO_3$ 0.2%, MgS $O_4$..$7H_2$O 0.05%, $KH_2$$PO_4$ 0.05%(pH6.5) at $30^{\circ}C$ for 4 days. Acetylcholinesterase inhibitor was purified by Diaion WA-30($OH^{-}$) column charomatography and cellulose column chromatography. Acetylcholinesterase inhibi-tor showd the maximum wavelength at 205 nm and was soluble in water, acetic acid, ethanol, methanol and dime-thyl sulfoxide. The concentration of 50% inhibition($IC_{50}$) of inhibitor against acetylcholinesterase was 25$\mu\textrm{g}$/ml. The inhibitor was inactivated on heating ar $100^{\circ}C$ fro 15 min and more stable in acidic region than alkaline region.n.