• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2002.10a
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• pp.89-91
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• 2002

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.126-129
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• 2008

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.5
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• pp.352-358
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• 2001

Because algal cells are so efficient at absorbing incoming light energy, providing more light energy to photobioreactors would simply decrease energy conversion efficiency. Furthermore, the algal biomass productivity in photobioreactor is always proportional to the total photosynthetic rate. In order to optimize the productivity of algal photobioreactors (PBRs), the oxygen production rate should be estimated. Based on a simple model of light penetration depth and algal photosynthesis, the oxygen production rate in high-density microalgal cultures could be calculated. The estimated values and profiles of oxygen production rate by this model were found to be in accordance with the experimental data. Optimal parameters for PBR operations were also calculated using the model.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.3
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• pp.189-193
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• 2001

Critical cell density (CCD), the maximum cell concentration without mutual shading in algal cultures, can be used as a new operating parameter for high-density algal cultures and for the application of the flashing light effect on illuminated algal cultures. CCD is a function of average cell volume and light illumination area. The CCD is thus proposed as an index of estimation of mutual shading in algal cultures. Where cell densities are below the CCD, all the cells in photobioreactors can undergo photosysnthesis at their maximum rate. At cell densities over CCD, mutual shading will occur and some cells in the illumination chamber cannot grow photoautotrophically. When the cell concentration is higher than the CCD, specific oxygen production rates under flashing light were higher than those under continuous light. The CCD was found to be a useful engineering parameter for the application of flashing light, particularly in high-density algal cultures.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.442-446
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• 2005

Fungicidal activities of Cassia obtusifolia extracts and their active principles were tested against Botrytis cinerea, Erysiphe graminis, Phytophthora infestans, Puccinia recondita, Pyricularia grisea, and Rhizoctonia solani, and compared with synthetic fungicides and two dihydroxyanthraquinones. At 1 g/l, the chloroform fraction of C. obtusifolia extracts showed fungicidal activity against B. cinerea, E. graminis, P. infestans, and Py. grisea, and the ethyl acetate fraction showed fungicidal activity against E. graminis and P. infestans. Danthrone was chromatographically isolated from the chloroform fraction and showed fungicidal activity against B. cinerea, E. graminis, P. infestans, and Py. grisea with 68, 100, 78, and $91\%$ control values at 0.5 g/l, respectively. Specifically, alizarin and quinizarin inhibited E. graminis, P. infestans, and Py. Grisea, but did not inhibit the growth of P. recondita and R. solani. These results indicate at least one of the fungicidal actions of danthrone.

• Food Science and Industry
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• v.52 no.4
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• pp.346-357
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• 2019

In recent years, starch nanoparticles (SNPs) have been received much attention due to their unique characteristics different from native starch. Also, SNPs have economic and environmental advantages because they are prepared from starch, a cheap and safe natural polymer. It can be used in various industrial applications such as food additives, drug carriers, etc. SNPs have been prepared using different methods and their physiochemical, functional properties and possible industrial applications have been reported. Based on these studies, SNPs are expected to be the promising food materials and expand their utilization in many industries in the future. This review covered the overall researches on SNPs, including preparation, physicochemical and functional properties, and discussed their current and future applications including resistant starch materials.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.70-70
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• 2003

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.71-71
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• 2003

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2004.10a
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• pp.96-96
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• 2004

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.503-508
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• 2011

A ${\beta}$-glucosidase from Phoma sp. KCTC11825BP isolated from rotten mandarin peel was purified 8.5-fold with a specific activity of 84.5 U/mg protein. The purified enzyme had a molecular mass of 440 kDa with a subunit of 110 kDa. The partial amino acid sequence of the purified ${\beta}$-glucosidase evidenced high homology with the fungal ${\beta}$- glucosidases belonging to glycosyl hydrolase family 3. Its optimal activity was detected at pH 4.5 and $60^{\circ}C$, and the enzyme had a half-life of 53 h at $60^{\circ}C$. The $K_m$ values for p-nitrophenyl-${\beta}$-D-glucopyranoside and cellobiose were 0.3 mM and 3.2 mM, respectively. The enzyme was competitively inhibited by both glucose ($K_i$=1.7 mM) and glucono-${\delta}$-lactone ($K_i$=0.1 mM) when pNPG was used as the substrate. Its activity was inhibited by 41% by 10 mM $Cu^{2+}$ and stimulated by 20% by 10 mM $Mg^{2+}$.