• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.69-73
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• 2018

Oak mushroom (Lentinus edodes) is cultivated by using oak logs and sawdust medium. Green mold (Trichoderma) infection on these media severely suppresses the growth of oak mushroom. Usages of antibiotics and chemicals are not generally allowed to control of green mold since the mushroom is a fresh food. Tolaasin and its analogues, peptide toxins secreted by Pseudomonas tolaasii, have the antifungal activity and they have been successful to control the green mold disease. When the green mold, Trichoderma harzianum H1, was cultured in the presence of these toxins, the growth of fungus was effectively suppressed. In sawdust media, when the bacterial culture supernatants were sprayed on the aerial hyphae of green molds, the fungal growth was completely suppressed. Particularly, the antifungal activity was greatly increased by the combined culture extracts of P. tolaasii 6264 and HK11 strains. Therefore, these bacterial strains and their peptide toxins were able to suppress the growth of green molds and these can be good candidates to prevent from Trichoderma disease in oak mushroom cultivation.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.681-686
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• 2004

Ti-ZSM-5 prepared by secondary synthesis, from the reaction of H-ZSM-5 with vapor phase $TiCl_4$, was characterized with several physicochemical techniques including FT-IR and UV/VIS-DRS. It was found that zeolite structure, surface area and pore volume did not change, and the framework aluminum could not be replaced by titanium atom during the secondary synthesis of Ti-ZSM-5. The incorporation of titanium into the framework might be due to reaction of $TiCl_4$with the silanol groups associated with defects or surface sites. The formation of extra-framework titanium could not be avoided, unless the samples were further treated by water vapor at 550 $^{\circ}C$ or higher temperature. High temperature steam treatment of Ti-ZSM-5 prepared by chemical vapor deposition with $TiCl_4$was efficient to prevent the formation of non-framework titanium species. Ti-ZSM-5 zeolites prepared in this work contained only framework titanium species and exhibited improved catalytic property close to TS-1 prepared by hydrothermal synthesis.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2041-2043
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• 2013

A layered perovskite of Dion-Jacobson phase, $RbLaTa_2O_7$, was successfully exfoliated into colloidal suspension via successive ion-exchange and intercalation reaction. The pristine perovskite $RbLaTa_2O_7$ was synthesized by conventional solid-state reaction, and then, it was ion-exchanged with hydrochloric acid to obtain a protonic form of perovskite. The resulting proton-exchanged perovskite was reacted with ethylamine to increase interlayer spaces for further intercalation reaction. Finally, the ethylamine-intercalated form was exfoliated into nanosheets via an intercalation of bulky organic cations (tetrabutylammonium). According to X-ray diffraction (XRD) analysis, the TBA-intercalated form showed remarkably increased interlayer spacing (${\Delta}d$ = 1.67 nm) in comparison with that of the pristine material. Transmission electron microscopic image of exfoliated perovskite clearly revealed that the present exfoliated perovskite were composed of very thin layers. This exfoliated perovskite nanosheets could be applicable as building blocks for fabricating functional nanocomposites.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3919-3922
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• 2013

• Journal of the Korean Chemical Society
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• v.26 no.2
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• pp.95-98
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• 1982

A new chemical constituent was isolated from the green leaves of Ginkgo biloba L. and identified as 3-(pentadec-8-enyl) phenol.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1589-1592
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• 2004

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.267-270
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• 2013

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.121-126
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• 2004

The primary goal of six sigma is to improve patient satisfaction, and thereby profitability, by reducing and eliminating defects. Defects may be related to any aspect of customer satisfaction: high product quality, schedule adherence, cost minimization, process capability indices, defects per unit, and yield. Many six sigma metrics can be mathematically related to the others. Literally, six means six standard deviations from the mean or median value. As applied to quality metrics, the term indicates that failures are at least six standard deviations from the mean or norm. This would mean about 3.4 failures per million opportunities for failure. The objective of six sigma quality is to reduce process output variation so that on a long term basis, which is the customer's aggregate experience with our process over time, this will result in no more than 3.4 defect Parts Per Million(PPM) opportunities (or 3.4 Defects Per Million Opportunities. For a process with only one specification limit (upper or lower), this results in six process standard deviations between the mean of the process and the customer's specification limit (hence, 6 Sigma). The results of applicative six sigma experiment studied on 18 items TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA tests in clinical chemistry were follows. Assessment of process performance fits within six sigma tolerance limits were TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA with 72.2%, items that fit within five sigma limits were total bilirubin, chloride and sodium were 3 sigma. We were sure that the goal of six sigma would reduce test variation in the process.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.149-153
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• 2017

Contamination and growth of Trichoderma, a green mold, on the oak log and wooden chip or sawdust media can severely inhibit the growth of oak mushroom. Chemicals including pesticides and antibiotics are generally not allowed for the control of green mold disease during mushroom cultivation. In this study, bacterial pathogens causing blotch disease on the oyster mushrooms were isolated and their peptide toxins were purified for the control of green mold disease. Strains of Pseudomonas tolaasii secret various peptide toxins, tolaasin and its structural analogues, having antifungal activities. These peptides have shown no effects on the growth of oak mushrooms. When the peptide toxins were applied to the green mold, Trichoderma harzianum H1, they inhibited the growth of green molds. Among the 20 strains of peptide-forming P. tolaasii, strong, moderate, and weak antifungal activities were measured from 8, 5, and 7 strains, respectively. During oak mushroom cultivation, bacterial culture supernatants containing the peptide toxins were sprayed on the aerial mycelia of green molds grown on the surface of sawdust media. The culture supernatants were able to suppress the fungal growth of green molds while no effect was observed on the mushroom growth and production. They changed the color of molds from white aerial mycelium into yellowish dried scab, representing the powerful anti-fungal and sterilization activities of peptide toxins.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.1961-1966
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• 2013

Theoretical investigations have been performed for the ground state ($S_0$) and the first excited state ($S_1$) of the hydrogen bonded green fluorescent protein (GFP) model. The potential energy surface (PESs) of $S_0$ was obtained by B3LYP method and that of $S_1$ was obtained by CIS method. Based on the relative stabilities of species and the energy barriers for the proton transfer, it was found that proton transfer could take place both under the ground state and the first excited state. As determined by the proton motions along the reaction coordinate, both the ground state proton transfer (GSPT) and the excited state proton transfer (ESPT) are considered as a concerted and asynchronous process.