• Korean journal of applied entomology
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• v.50 no.4
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• pp.307-314
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• 2011

Cordyceps (vegetable wasp and plant worm), an entomopathogenic fungi, has been used as a herbal medicine in Asian countries since ancient times. Cordyceps nutans is common but there is little research on this species. This study investigated the optimal culture conditions of C. nutans and the inhibitory effect on nitric oxide (NO) production in RAW 264.7 cell treated culture broth. The optimal conditions for the mycelial growth were $25^{\circ}C$ and pH 7.0-8.0. Mycelial growth was highest on mushroom complete medium (MCM), V8 juice agar (V8A), and yeast malt dextrose (YMD) medium. Mycelial growth on mushroom minimal medium (MMM) did not occur, so nutrient source was essential. Dextrose and sucrose as carbon sources, and ammonium citrate as a nitrogen source were satisfactory for mycelial growth. Cytotoxicity of C. nutans culture broth was not found in RAW 264.7 cells. C. nutans culture broth suppressed NO production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cell in a dose-dependent manner. Thus, our results provided the optimal conditions for cultivation of C. nutans and showed that C. nutans may have excellent physiological activities.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.145-152
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• 2013

The culture conditions to maximize the production of endoglucanase (EC 3.2.1.4) from the brown rot fungus Fomitopsis pinicola MKACC 54347 mycelia were investigated. Among the tested media for endoglucanase production, Mandel's mineral salts medium (MSM; 1% cellulose, 0.1% peptone, 0.14% $(NH_4)_2SO_4$, 0.03% urea, 0.2% $KH_2PO_4$, 0.03% $MgSO_4{\cdot}7H_2O$, 0.03% $CaCl_2$, and 0.1% trace metal solution (19.8 mM $FeSO_4$, 13.0 mM $MnSO_4$, 12.2 mM $ZnSO_4$, and 15.4 mM $CoCl_2$)) produced the highest activity of the enzyme. To optimize the medium composition for enzyme activity, the effects of various carbon, nitrogen, phosphorus, and inorganic sources were investigated in MSM. Maximal enzyme production was accomplished using a medium containing 2% carboxymethyl cellulose (CMC), 2% yeast extract, 0.2% $KH_2PO_4$, 0.03% $MnSO_4$, and 0.3% trace metal solution. Different physiological conditions, like incubation period and temperature, were also examined to assess their influence on enzyme production. Enzyme production from F. pinicola reached its highest level after cultivation for 8 days at $25^{\circ}C$. Nondenaturing polyacrylamide gel electrophoresis (PAGE), followed by the endoglucanase activity staining using CMC as the substrate, was performed to identify the endoglucanase under the culture conditions studied. Zymogram analysis of the culture supernatant revealed an endoglucanase band with a molecular mass of 52 kDa. The optimum pH and temperature for enzyme activity were $55^{\circ}C$ and pH 5.0, respectively.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.479-483
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• 2006

[ ${\beta}-Glucan$ ], one of the cell wall components, is most plentiful polysaccharides in cell wall and has several advantages in immune system. In yeast ${\beta}-glucan$ is mainly contained in the yeast cell wall, and thus it is important to produce high levels of cell mass for the mass production of yeast ${\beta}-glucan$. The best carbon and nitrogen sources on cell mass production were high fructose syrup and yeast extract. Response surface methodology (RSM) was very potential tool for the optimization of process factor and medium component. It was applied to estimate the effects of medium components on the production of cell mass. Optimal concentrations of high fructose syrup and yeast extract by response surface methodology were 8.0% (v/v) and 5.2% (w/v), respectively and the cell mass predicted was $17.0\;g/{\ell}$ at 20 h of cultivation.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.197-203
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• 2021

Saponarin is a crucial component of barley sprout, and the production and quantitative analysis are issued to date. In this study, the optimal saponarin extraction conditions were presented on the subject of acetonitrile, ethanol, methanol, and water for the quantitative analysis in barley sprout through the extraction efficiency compared with the solvent concentration and extraction time using the reaction surface methodology. The optimal extraction time and solvent condition for saponarin were 3.9 h and 53.7% of aqueous methanol, respectively. In addition, the effect of LED artificial light on the saponarin production in barley sprouts was evaluated by the light cycle, light quantity, and light quality. The optimal cultivation conditions under artificial light for the growth of barley sprout and saponarin production were most effectively achieved on 220-320 μmol m^-2 s^-1 of the light quantity with 8 h day^-1 of a daylight cycle under 6500K LED combined with red light. Furthermore, blue light was evaluated as the main factor in the biosynthesis of saponarin.

• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.26-31
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• 1999

The advantages of the organism Streptomycs griseus HUT 6037 is that the chitinase and chitosanase using chitinaceouse substrate are capable of hydrolyzing both amorphous and crystalline chitin and chitosan. We attempted to investigate the optimization of induction protocol for high-level production and secretion of chitosanase and the influence of chitin and partially deacetylated chitosan sources (75∼99% deacetylation). The maximum specific activity or chitinase has been found at 5 days cultivation with the 48 hours induction time using colloidal chitin as a carbon source. To investigate characteristic of chitosan activity according to substrate, we used chitosan with various degree of deacetylation as a carbon source and found that this strain accumulates chitosanase in the culture medium using chitosanaceous substrates rather than chitinaceous substrates. The highest chitosanase activity was also presented on 4 days with 99% deacetylated chitosan. The partially 53% deacetylated chitosan can secrete both chitinase and chitosanase which was defined as a soluble chitosan. The specific activities of chitinase and chitosanase were 0.89 at 3 days and 1.33 U/mg protein at 5 days, respectively. It indicate that chitosanase obtained from S. griseus HUT 6037 can hydrolyze GlcNAc-GlcN and GlcN-GlcN linkages by exo-splitting manner. This activity increased with increasing degree of deacetylation of chitosan. It is the first attempted to investigate the effects of chitosanase on various degrees of deacetylations of chitosan by S. griseus HUT 6037. The highest specific activity of chitosanase was obtained with 99% deacetylated chitosan.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.388-393
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• 2017

We report an Agrobacterium-mediated transformation procedure optimized for 'Kyoho' that is a major table grapevine cultivar in Korea, and its transgenic plants with antifreeze protein gene of carrot (DcAFP). The full length of DcAFP coding region in accordance with the previous report was isolated from young leaves of carrot and recombined into a plant transformation vector. Ethylene inhibitors such as silver nitrate and aminoethoxyvinylglycin (AVG) supplemented in a co-cultivation medium distinctly increased frequency of shoot regeneration when explants were sub-cultured in a selection medium: particularly ten-fold higher in treatment with 0.1 mg/L AVG than one without ethylene inhibitor. Among various antibiotics and their concentrations, the combination of 150 mg/L cefotaxime plus 150 mg/L $Clavamox^{TM}$ was selected for elimination of Agrobacterium cells in addition to minimization of adverse effect on shoot regeneration, while 50 mg/L kanamycin monosulfate effectively suppressed regeneration of non-transgenic shoots. Applying the elucidated culture condition, we finally obtained a total of 5 transgenic 'Kyoho' plantlets with DcAFP, of which integration with the grapevine genome and transcription was confirmed by nucleic acid analyses.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.355-360
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• 2000

A UVmutant of Candida rugosa IF00750 was made and used to convert butYlic acid to D-$\beta$-hydroxybutyric acid(D-$\beta$-HBA). Major regulating factors for D-$\beta$-HBA fennentation were investigated via chemostat analyses. The maximum specific productivity was achieved at a specific growth rate of $0.06h^{-1}$ where the glucose and butyric acid concentrations in the fermentor were 10 g/L and 8.7 g/L. respectively. A fed-batch fennentation was performed with maintenance of the optimum glucose and butyric acid concentrations. The D-$\beta$-HBA concentration after 120 h of cultivation reached 12.4 g/L, which was 4.7 times greater illan the concentration obtained by batch fermentation.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.947-955
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• 2017

Herbicidin A is a potent herbicide against dicotyledonous plants as well as an antibiotic against phytopathogens. In this study, fermentation parameters for herbicidin A production in submerged culture of Streptomyces scopuliridis M40 were investigated. The herbicidin A concentration varied with the C/N ratio. High C/N ratios (>4) resulted in a herbicidin A production of more than 900 mg/l, whereas maximally 600 mg/l was obtained at ratios between 1 and 3.5. In 5-L batch fermentation, there was a positive correlation between the oxygen uptake rate (OUR) and herbicidin A production. Once the OUR increased, the substrate consumption rate increased, leading to an increase in volumetric productivity. Mechanical shear force affected the hyphal morphology and OUR. When the medium value of hyphal size ranged from 150 to $180{\mu}m$, high volumetric production of herbicidin A was obtained with OUR values >137mg $O_2/l{\cdot}h$. The highest herbicidin A concentration of 956.6 mg/l was obtained at 500 rpm, and coincided with the highest relative abundance of hyphae of $100-200{\mu}m$ length and the highest OUR during cultivation. Based on a constant impeller tip speed, which affects hyphal morphology, herbicidin A production was successfully scaled up from a 5-L jar to a 500-L pilot vessel.

• KSBB Journal
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• v.14 no.6
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• pp.731-736
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• 1999

87 microbes were isolated from dyeing wastewater collected at Dongducheon and Banweol industrial complex. Five microbes showed excellent ability of color removal and were identified as Shewanella putrefaciens, Aeromonas salmonicida(3 different strains), and Pseudomonas vesicularis. Five identified strains had optimal pH and optimal temperature as 7.0 and 30$^{\circ}C$ for cultivation, and showed morphological characteristics of Gram negative, oxidase negative, rod shape, and non-motility, but their biochemical characteristics were distinguishable. Each single strain of five microbes were tested in the 500 mL flask to treat dyeing wastewater, and achieved about 35% color removal efficiency in average. When two strains were selected and applied to the treatment at same time, color removal efficiency was increased up to 65%. While three or more associations of each strain did not show the improvement of color removal. Inhibition effects by $Mn^{2+}\;and\;Fe^{3+}$ on the dye degradation were tested and resulted in no effect under 70 ppm concentration.

• BMB Reports
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• v.32 no.1
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• pp.86-91
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• 1999

The sprT gene encoding Streptomyces griseus trypsin (SGT) was introduced into Streptomyces lividans TK24 and Streptomyces lividans 1326 to study which strain would be better to overexpress the extracellular proteinase. Various media with different compositions were also used to maximize the productivity of SGT in heterologous hosts. The SGT productivity was best when the transformants of S. lividans TK24 and 1326 were cultivated in R2YE medium, and their relative trypsin activity of the culture broth measured with an artificial chromogenic substrate, N-${\alpha}$-benzoyl-DL-arginine-${\rho}$-nitroanilide, were 382 units/ml and 221 units/ml, respectively. They produced high levels of SGT in GYE medium but relatively lower than those in R2YE medium, and negligible amount of SGT was produced in Ferm, RASF, LIVID, and NDSK media. Considering non-SGT associated activity in Pronase powder, it was estimated that the transformant of S. lividans TK24 can produce SGT in R2YE 3.5 times more than the amount by S. griseus 10137 from which the sprT gene had been originated. The growth of S. lividans reached the maximum level of cell mass at 5 d of culture, but SGT production started in the stationary phase of cell growth and kept increasing until the ninth day of culture in R2YE medium, but in GYE media the productivity reached at the maximum level at 7 d of cultivation.