• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1385-1392
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• 2009

This work evaluates the effect of different amino acids on production of Cyclosporin (CyA) production in solid-state fermentation that was previously optimized for different fermentation parameters by one factor at-a-time for the maximum production of CyA by Tolypocladium inflatum MTCC557. Based on the Plackett-Burman design, glycerol, ammonium sulfate, $FeCl_3$, and inoculum size were selected for further optimization by response surface methodology (RSM). After identifying effective nutrients, RSM was used to develop mathematical model equations, study responses, and establish the optimum concentrations of the key nutrients for higher CyA production. It was observed that supplementation of medium containing (% w/w) glycerol, 1.53; ammonium sulfate, 0.95; $FeCl_3$, 0.18; and inoculum size 6.4 ml/5g yielded a maximum of 7,106 mg/kg as compared with 6,480 mg CyA/kg substrate using one factor at-a-time. In the second step, the effect of amino acids on the production of CyA was studied. Addition of $_L$-valine and $_L$-leucine in combination after 20 h of fermentation resulted in maximum production of 8,166 mg/kg.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.587-593
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• 2011

As a result of increasing environmental concerns related to air quality and maintenance of automobiles, the alkylation of isobutane with olefins has become an even more important process for production of high quality gasoline. However, the widespread use of the alkylation process is limited by the polluting and corrosive liquid acid catalysts (HF and $H_2SO_4$) currently used in industry. For the reason, a large number of solid catalysts, especially zeolites, have been studied as an environmental friendly catalyst in this process. Recently, mesoporous solid acids and ionic liquids have been investigated as a green catalyst. In this review, the research of environmental friendly catalysts for an isobutane alkylation is summarized.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2005.09a
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• pp.124-132
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• 2005

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.801-806
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• 2002

Cyclicpeptides are important targets in peptide synthesis because of their interesting biological properties. Constraining highly flexible linear peptides by cyclization is one of the mostly widely used approaches to define the bioactive conformation of peptides. Cyclic peptides often have increased receptor affinity and metabolic stability over their linear counterparts. We carried out virtual screening experiment via docking in order to understand the interaction between HLE-Human Leukocyte Elastase and ligand peptide and to identify the sequence that can be a target in various ligand peptides. We made cyclic peptides as a target base on Metlle-Phe sequence having affinity for ligand and receptor active site docking. There are three ways to cyclize certain sequences of amino acids such as Met-lie-Phe-Gly-Ile. First is head-to-tail cyclization method, linking between N-terminal and C-terminal. Second method utilizes amino acid side chain such as thiol functional group in Cys, making a thioether bond. The last one includes an application of resin-substituted amino acids in solid phase reaction. Among the three methods, solid phase reaction showed the greatest yield. Macrocyclization of Fmoc-Met-Ile-Phe-Gly-Ile-OBn after cleavage of Fmoc protection in solution phase was carried out to give macrocyclic compound 5 in about 7% yield. In the contrast with solution phase reaction, solid phase reaction for macrocyclization of Met-Ile-Phe-Gly-Ile-Asp-Tentagel in normal concentrated condition gave macrocyclic compound 7 in more than 35% yield.

• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.235-236
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• 1994

Direct colony hybridization on agarose gel plate was established for the identification of recombinant plasmids. The hybridization of the probe to nucleic acids on dried gel without transferring to solid supports was more effective and simpler than hybridization of such probes to materials immobilized on filters such as nitrocellulose or nylon. D-cycloserine in overlaying agamse was essential for releasing the nucleic acids from colony.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.665-669
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• 1994

A rapid gas chromatographic (GC) profiling method was applied to dairy products (milk and cheeses) for the simultaneous analysis of volatile and nonvolatile organic acids. Cheese samples were first made into aqueous samples by dissolving in water. The aqueous samples were then extracted with organic solvents after the acidification and NaCI saturation. The organic layers (diethyl ether : hexane= 1 : 1) were extracted with $NaHCO_3$ saturated solution with subsequent solid-phase extraction of the aqueous phases using Chromosorb P column/diethyl ether followed by triethylamine treatment. The resulting triethylammonium salts of acids were directly converted into volatile tert.-butyldimethylsilyl derivatives, which were analyzed by dual-capillary column GC, and GC-mass spectrometry. From milk and four cheese samples studied, 31 organic acids including 21 fatty acids and other hydroxy and dioic acids were tentatively identified. The amounts of the fatty acids were different among the kinds of cheese and thus the simplified retention index (RI) spectra of organic acids were useful for the visual pattern recognition of each sample, when the Direct Comparision method between cheese and a blind sample were attempted, it was quickly recognized to be a gouda cheese with the 999 ppt match quality value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.10
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• pp.1438-1446
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• 2011

Palmitoyl-oleoyl-oleoyl (POO) and palmitoyl-oleoyl-palmitoyl triacylglycerol rich fraction (PSL) was obtained from the acetone fractionation of palm stearin. The fatty acid composition (total and positional), tri-acylglycerol species, and solid fat index (SFI) were compared among the blends of natural vegetable fats (sal fat, illipe fat, kokum fat, shea stearin fat, and shea butter) and PSL with different ratios (50:50, 60:40, 65:35, 70:30). In total fatty acid composition of PSL, palmitic, oleic, and linoleic acids were the major fatty acids, whereas in natural vegetable fats stearic and palmitic acids were the major fatty acids. Moreover, oleic acid was a major fatty acid at sn-2 position in sal fat, illipe fat, and kokum fat. The TAG species was analyzed by reversed-phase HPLC, from which the PN value ranged from 46 to 54. When natural vegetable fats and PSL were blended with different ratios, decreasing the amount of PSL resulted in increasing SFI in most cases. Among blends, the SFI of sal fat and PSL were most similar to commercial cocoa butter equivalent (CBE).

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.19-22
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• 1989

The suitability of BMPI (2-bromo-N-methyl pyridinium iodide) for solid-phase peptide synthesis was investigated. The coupling rate of BMPI/HOBT procedure. BMPI/HOBT was superior to DCC/HOBT couplings using the solid-phase peptide bond formation proceeded to a greater degree of completion than DCC/HOBT method did. Double couplings with 2 equiv. of Bocamino acids and 1.5 equiv. of BMPI and $NEt_3$ and 2 equiv. of HOBT in DMF/MC (1:1 v/v) gave the best result for the preparation of a model compound. Stepwise solid phase peptide synthesis using BMPI/HOBT procedure was successfully utilized for the preparation of $(D-Ala)^2$-dynorphine A. BMPI/HOBT procedure for the synthesis of $(D-Ala)^2$-dynorphine gave better yield (20%) than DCC/HOBT procedure did.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.654-662
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• 2024

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to Mucoromycota, including Lichtheimia, Mucor, Rhizomucor, and Rhizopus, produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to Aspergillus subgenus circumdati. The genera Penicillium and Scopulariopsis produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to Aspergillus subgenus circumdati, including A. oryzae, showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of A. oryzae as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.803-807
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• 2009

Solid fats were esterified with solid phase of rice bran oil (S-RBO), palm stearin (PS), and conjugated linoleic acid (CLA) at 2 substrate mole ratios (S-RBO:PS:CLA of 1:1:2 and 1:3:4). The major fatty acids were palmitic, oleic, and CLA in 36 hr products. The solid fat content (SFC) of the 1:1:2 product was 12.8% while the SFC of 1:3:4 product was 45.1% at $20^{\circ}C$. The SFCs after $20^{\circ}C$ reduced when the reaction time increased from 1 to 36 hr, suggesting that the change of triacylglycerol species was augmented by extending reaction time.