• Journal of the East Asian Society of Dietary Life
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• v.4 no.2
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• pp.39-44
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• 1994

To prepare the basic information for the fermentation of high quality persimmon vinegar in the farm. the quality of the complex fermented persimmon vinegar(CFPV) was compared to that of naturally fermented persimmon vinegar (NFPV). The titratable acidity of the CFPV was 3% which was the half concentration of the NFPV. The content of total free sugar by HPLC was 6% in CFPV and NFPV was 5%. Organic acid compositions in persimmon vinegar were oxalic acid, malic acid, lactic acid, citric acid, succinic acid and glutaric acid in addition to acetic acid. Total content of the organic acids in NFPV was higer than in CFPV. Especially, the content of latic acid in NFPV was very higher than that of CFPV. the flavour, color and taste of persimmon fruit itself in CFPV were stronger than those in NFPV.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_3
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• pp.127-137
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• 2001

The sonochemical Process has been applied as a treatment method and was investigated its effect on the decomposition of humic substances(HS). The reaction kinetics and mechanisms in the Process of sonochemical treatment for humic substances(HS) in wastewater have also been discussed. It was observed that the metal ions such as Fe(II) and Mn(II) showed catalytic effects, while Al(III), Ca(II), and Mg(II) had inhibitory effects on the decomposition of humic substances in sonochemical reaction with hydrogen peroxide. Experimental results also showed factors such as hydrogen peroxide dose affected the formation of disinfection by-products. Two trihalomethanes, chloroform and dichlorobromomethane were formed as major disinfection by-products during chlorination. The mechanism of radical reaction is controlled by an oxidation process. The radicals are so reactive that most of them are consumed by HS radicals and hydroxyl radicals can be acted on organic solutes by hydroxyl addition, hydrogen abstraction, and electron transfer. The depolymerization and the radical reaction of HS radicals appear to occur simultaneously. The final steps of the reaction are the conversion of organic acids to carbon dioxide.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.176-181
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• 2004

This study was carried out to investigate the effect of yucca extract on the quality characteristics of Chungkookjang using Bacillus subtilis p01. The changes in the contents of amino-type N, ammonia type N, volatile compounds and organic acids, and those in the activities of ${\alpha}-amylase$ and protease were also determined during aging of Chungkookjang. The amount of amino-type N increased gradually with time for aging. The content of amino-type N was slightly higher in Chungkookjang fermented by adding yucca extract than in the control without yucca extract. The content of ammonia-type N was slightly lower in Chungkookjang with yucca extract than in the control without yucca extract. The activities of amylase and protease were higher in Chungkookjang with yucca extract than in the control and the highest in Chungkookjang containing 0.5 mg/g of yucca extract. Organic acid contents in Chungkookjang was the highest at the initial period of fermentation. The contents of organic acids in Chungkookjang with yucca extract was higher than that in control for 48 hr of aging. The amounts of 2,5-dimethylpyrazine were increased by addition of yucca extract, while those of cis-3-hexanol were decreased.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.469-475
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• 1993

The approximate rates and stoichiometry of the reaction of excess lithium tris(diethylamino)aluminum hydride (LTDEA) with selected organic compounds containing representative functional groups under standardized condition (tetrahydrofuran, 0$^{\circ}C$) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of LTDEA was also compared with those of the parent lithium aluminum hydride (LAH) and lithium tris(dibutylamino)aluminum hydride (LTDBA). In general, the reactivity toward organic functionalities is in order of LAH${\gg}$LTDEA${\geq}$LTDBA. LTDEA shows a unique reducing characteristics. Thus, benzyl alcohol and phenol evolve hydrogen slowly. The rate of hydrogen evolution of primary, secondary, and tertiary alcohols is distinctive: 1-hexanol evolves hydrogen completely in 6 h, whereas 3-hexanol evolves hydrogen very slowly. However, 3-ethyl-3-pentanol does not evolve any hydrogen under these reaction conditions. Primary amine, such as n-hexylamine, evolves only 1 equivalent of hydrogen. On the other hand, thiols examined are absolutely inert to this reagent. LTDEA reduces aldehydes, ketones, esters, acid chlorides, and epoxides readily to the corresponding alcohols. Quinones, such as p-benzoquinone and anthraquinone, are reduced to the corresponding diols without hydrogen evolution. However, carboxylic acids, anhydrides, nitriles, and primary amides are reduced slowly, where as tertiary amides are readily reduced. Finally, sulfides and sulfoxides are reduced to thiols and sulfides, respectively, without evolution of hydrogen. In addition to that, the reagent appears to be an excellent partial reducing agent to convert esters, primary carboxamides, and aromatic nitriles into the corresponding aldehydes. Free carboxylic acids are also converted into aldehydes through treatment of acyloxy-9-BBN with this reagent in excellent yields.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.144-150
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• 2011

This study was conducted to investigate the nutrient components and physicochemical properties of general ('Superior') and colored potato. Proximate composition, reducing sugar, free sugars, free amino acids, organic acids, minerals were analyzed, and Hunter color values were measured in the study. 'Rose' and 'Blue' (colored potatoes) contained high levels of reducing sugar, and total free sugar content was greatly different according to varieties. Glutamic acid, arginine and ${\gamma}$-aminobutyric acid were detected to be the three major amino acids in colored potato, and the major organic acids of general potato were oxalic acid, tartaric acid, malic acid and citric acid. All potato contained high level of potassium, calcium and magnesium. The Hunter 'L' value was the highest in 'Jaseo'; Hunter 'a' value was high in 'Blue' and 'Jasim'; Hunter 'b' value was the highest in 'Haryoung'. Overall, colored potato had higher amount of nutrients and physicochemical properties than 'Superior'. Therefore, colored potatoes are expected to be highly valuable items for the development and applications of a functional food. In addition, these results will provide fundamental data for improving sitological value, breeding of new cultivar and promoting of roughage usage.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.317-326
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• 2021

Vanillyl alcohol (VA), which is abundant in Vanilla bean, has strong antioxidant activity. However, the use of VA in the food and cosmetics industries is limited, due to its low solubility in emulsion or organic solvents. Meanwhile, medium chain fatty acids and medium chain monoglycerides have antibacterial activity. We synthesized butyric acid vanillyl ester (BAVE) or caprylic acid vanillyl ester (CAVE) from VA with tributyrin or tricaprylin through transesterification reaction using immobilized lipases. BAVE and CAVE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals in organic solvents. In addition, BAVE and CAVE decreased the production rate of conjugated diene and triene in the menhaden oil-in-water emulsion system. While BAVE showed no antibacterial activity, CAVE showed antibacterial activity against food spoilage bacteria, including Bacillus coagulans. In this study, the antibacterial activity of vanillyl ester with medium chain fatty acid was first revealed. Zeta potential measurements confirmed that BAVE and CAVE were inserted into B. coagulans membrane. In addition, the propidium iodide uptake assay and fluorescent microscopy showed that CAVE increased B. coagulans membrane permeability. Therefore, CAVE is expected to play an important role in the food and cosmetics industries as a bi-functional material with both antioxidant and antibacterial activities.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.7
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• pp.426-439
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• 2017

This review summarizes advantage and limitation in infrared spectroscopy and computational chemistry to understand rhizospheric interaction among organic acids, oxyanions and metal oxides. Since organic acids and metal oxides determine dynamics of oxyanions in the soil environment, knowledge of fundamental mechanisms is a prerequisite for understanding the interactions at soil-water interface. Attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) is a powerful tool to measure the interfacial reactions. However, the ATR-FTIR measurements are abstruse, because the optical characteristics for measurements are variable depending on the experimental setup. In addition, spectral overlapping is a primary obstacle to the analysis of the interfacial reaction; thus, it is essential to detect and to deconvolute bands for signal interpretation. In this review, we expained the fundamental principle for spectrum processing, and four band identification methods, such as derivative spectroscopy, two-dimension correlation spectroscopy, multivariate curve resolution, and computational chemistry with example of aqueous phosphate speciation. As a result, spectrum processing and computational chemistry improved interpretation and spectral deconvolution of overlapped spectra in relatively simple systems, but it was still unsatisfactory for the problems in more complexed system like nature. Nevertheless, we believed that our challenge would contribute practically to develop adequate analytical procedure, signal processing and protocols that could help to improve interpretation and to understand the interfacial interactions of oxyanions in natural systems.

• Clean Technology
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• v.17 no.3
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• pp.266-272
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• 2011

Anchovy oil was extracted using supercritical carbon dioxide ($SCO_2$) and organic solvents. Extraction was carried out at temperature range from 40 to $60^{\circ}C$, and pressure range from 15 to 25 MPa. The flow rate of $CO_2$ (22 $gmin^{-1}$) was constant entire the extraction period of 1.5 h. The fatty acid composition of anchovy oil was analyzed by gas chromatography (GC). The main fatty acids of anchovy oil were myristic acid, palmitic acid, stearic acid, palmitoleic acid, EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). In addition, the oil obtained by $SCO_2$ extraction contained a higher percentage of polyunsaturated fatty acids especially EPA and DHA comparing to the organic solvent extracted oil. The oxidative stability of oils extracted from Anchovy by $SCO_2$ extraction was compared to those extracted by organic solvents. Results showed that the storage periods of oils obtained by $SCO_2$ extraction were longer than those of organic solvents extraction.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.74-79
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• 2002

Three different kinds of the crude vinegars obtained from oak(Quercus serrata), bamboo(Phyllostachys pubescens) and pine(Pinus densiflora) species were stored for approximately one year and periodically analyzed to monitor their physicochemical changes. Small changes in physical properties, such as the pH, specific gravity and amount of organic acids as well as water-soluble tar were observed in the entire course of aging period. However, the color difference of the vinegars showed a remarkable change between 7 and 10 months. In addition, these vinegars' colors changed from light yellowish orange to much deeper purple and orange during this period. The amount of organic acids and neutral compounds(dihydro-2(3H)-furanone, furfural, furfuryl alcohol, 2-hydroxy-1-methyl-1-cyclopenten-3-one, 1-hydroxy-2-propanone and methanol) in the vinegars increased or decreased periodically every three months. A good linear relationship (correlation coefficient of ca. 0.92) was obtained between the amount of organic acids and the amount of neutral compounds in such changes. However, although the amount of phenols increased or decreased periodically, its amount was decreased over the entire aging.