• Journal of the Korean Home Economics Association
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• v.34 no.4
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• pp.403-414
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• 1996

The softening of the femented vegetables and the fruits was resulted from the degradation of pectin substances, cellulose, hemicellulose by polygalacturonase(PG), pectinesterase(PE), Cx-cellulase, $\beta$-galctosidase. The conversion of insoluble pectin to soluble pectin in cell wall-middle lamella was a major factor in the changes of firmness. Ca2+ was substantially increased firmness. However, Ca2+ could be removed from cell wall by chelating agents such as oxalic acid and citric acid. And Ca2+ was replaced with Na+ by ion exchange reaction. Ca2+ deficient tissue was vulnerable to attack by PG. Preheating treatment and Ca2+ addition is most effective in inhibiting the vegetable food softening and in increasing middle lamella-cell wall regidity, which PE activation by preheating treatment and Ca2+ addition could created more anionic carboxyl groups for cationic materials binding such as Ca2+ and chitosan and for polypectategel formation. Excessive demethylation by PE was associated with loosening of middle lamella cell wall components and softening.

• Membrane Journal
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• v.2 no.1
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• pp.49-58
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• 1992

Functionalized organic polymers have been used as supports for heterogenized homogeneous catalytic process[1]. Sprcific advantages of using these resins as support reagents have been reviewed[2-4]. These include: -ease of by-product separation from the main reaction product usuallyby simple filtration. -prevention of intermolecular reaction of reactive species or functional groups by simulating high dilution conditions[5]. -utility of the "fish-hook" principle in which a minor component in fished out of a large excess substrate by the insoluble polymer[6]. -the possibility of reusing recovered reagents as well as eliminating the use of volatile or noxious substances[7]. Catalysis by ion-exchange membranes is perhaps one of the latest examples of the use of a polymer-supported species. Conceptually, catalysts on membrane supports offer several possible advantages over traditional powder type systems. They are: (1) Membranes immobilize the catalyst, preventing agglomeration. (2) Filtration is unnecessary for the catalyst separation and so complete catalyst recovery is facilitated. (3) Catalytyic and separation processes can be combined, allowing membrane supported catalysts for the continous flow reactors. reactors.

• Journal of Ginseng Research
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• v.24 no.3
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• pp.107-112
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• 2000

One of the physiologically important ginseng diseases is red-colored phenomena (RCP) that is caused by accumulation of red-colored substances on the epidermis of ginseng roots. Although RCP severely deteriorates the quality of ginseng products, there has been little information on what red-colored substance is and how RCP occurs. Therefore, the heavy losses of cultivators and ginseng industry are suffering by RCP, For this reason, we have investigated with the morphochernical characteristics of RCP to find out main cause of it. The red-colored substances (RS) on the epidermis of red-colored ginseng (RCG) were examined using inverted light microscope, confocal laser scanning microscope (CLSM)and furier transform infrared (FT/IR) spectrometer. Red brown substances were accumulated in the cell wall of the epidermis from early stage to late stage of RCC. Especially, cell wall of the late stage of RCG was covered with the sub-stances with 80~ 130 fm thick. Therefore, the cell wall of RCG cannot protect the ginseng root cells from the mechanical damages, bacteria and fungi. To analyse red substances of roots, RS were isolated from epidermis of RCG and extracted using various solvents. RS is strongly insoluble but it was bleached by oxidizing agents including 12% (v/v) NaOCl. Therefore, RS was Presumed to make up of high chelation power. The proriles of FT/IR spectra or both healthy ginseng (HEG) and RCG showed a significant difference at two wavelength,2857 cm$\^$-1/(C-H) and 1032 cm$\^$-1/(S=O), respectively. Furthermore, absorption peak of 2857cm$\^$-l/ appears on the only epidermis of RCG. The other peak is shown lower absorption rate on the epidermis of RCG than that of healthy ginseng. Also, FT/IR spectra of the mixture of carboxym-ethylcellulose (CMC) and iron (Fe$\^$3+/) were very similar to RCG spectrum profiles. One of a interesting fact is that the contents of phenolic compounds at the epidermis of healthy ginseng were highest. The results of these experiments sup-port the RCP was closely related with the chemical interaction between inorganic elements (Fe) of rhizosphere and organic matters (cellulose, cellobiose, cell sap, etc.) of ginseng roots.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.126-132
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• 2001

This research is carried out to investigate the formation and preservative effectiveness of inorganic substance, calcium carbonate($CaCO_3$), in wood. The specimens were prepared by the impregnation with saturated solutions of potassium carbonate($K_2CO_3$) into the wood followed by precipitation in saturated solutions of calcium chloride($CaCl_2$) for 24h, 72h and 120h, and then they were leached in instrument flowing with water for 24h. The weight percent gains of $K_2CO_3$ solution impregnated specimens reached approximately a maximum value (108.1%) by 72h precipitation in $CaCl_2$ solutions. Inorganic substances were observed to he produced in the lumina of tracheids of specimens. From these inorganic substances filling in the tracheids, characteristic X-rays of calcium(Ca-$K_{\alpha}$) were detected by energy dispersive X-ray analyzer. Moreover, it was shown from a leaching treatment that these substances could not he leached easily from the specimens. Therefore, they were could he considered to be insoluble calcium carbonates. The weight losses of the prepared specimens were hardly occurred by test fungi attacks. Thus inorganic substances in specimens can be said to have preservative effectiveness.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.149-154
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• 2003

Changes in mineral (Ca, Mg) contents and pectic substances of mature-green 'Nanko' Mume fruits hermetically packaged in 0.03 mm low density polyethylene (LDPE) films with and without gas absorbents were examined during storage at $25^{\circ}C$ for 10 days. Each packaging contained 10 g $Ca(OH)_2$ as a carbon dioxide scavenger, 30 g $KMnO_4$ as an ethylene scrubber or their mixture. In the presence of the ethylene scrubber, losses in mineral contents of alcohol insoluble solids and water soluble pectin were remarkably suppressed, whereas no significant difference was observed in the Ca content between the fresh fruit and those stored for 10 days. Fruits packaged with the ethylene absorbent retained higher amount of pectic substances than those with other packaging treatments. Degradation of the pectic substances into small molecules was also noticeably reduced when the ethylene scrubber was used. Overall results showed that the combination of the gas permeable film and the ethylene absorbent could be applied to mature-green Mume fruits as an effective packaging method to retard the texture softening during storage at the ambient temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1664-1672
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• 2013

Solar salt is manufactured naturally, and therefore, it contains insoluble substances such as sandy compounds. This study is performed in order to effectively produce clean sea salt by removing the impurities in sea salt through filtration and evaporation in a vacuum condition. Brine was concentrated and crystallized at $90^{\circ}C$ by a rotary vacuum evaporator, which was then recovered as salt crystals by filtration, and then the salt was dehydrated. Manufacturing yields were determined by the amount of water evaporation. Brine was concentrated to 40%, 50% and 60% of the initial volume of brine and manufactured salt were designated as 40S, 50S and 60S, respectively. The salt produced by this process is called ESBS (evaporated salt with brine from salt-farm). The yield of 40S, 50S and 60S were 7.22%, 10.79% and 15.06%, respectively. The NaCl concentration of 40S and 50S were 90.38% and 91.16%, respectively. From a sensory evaluation analysis, the most tasty salt was 40S and the bitter salt was 60S. The average contents of sand compound and insoluble substances in ESBS were 0.001~0.012% and 0.067~0.12%, respectively. The mineral compositions, such as Na, Mg, K, and Ca of 40S and 50S were similar with those of the natural solar salt. In solubility tests, the solubility (g of salt/100 mL $H_2O$/sec) of 40S, 50S, and 60S was 0.69, 0.70, and 0.69, respectively. On the other hand, the solubility of natural solar salt was 0.47. By comparing the water reabsorption rate analysis results, water reabsorption rate of 40S and 50S was about 3 to 5 times lower than that of the solar salt. In the aspects of physical and chemical properties, such as minerals, impurities, solubility and moisture re-absorption rate, salts developed in this study are judged to be better than that of the general solar salt.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.144-155
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• 1987

Water extracts of polygonum hydropiper and Polygonum aviculare completely inhibited the germination of lettuce seeds. Methanol extracts from these two species also inhibited the seed germination of lettuce (Lactuca sativa) and Oenothera odorata. Fifteen phenolic acids in total were identified by GLC from P. hydropiper and eighteen from P. aviculare. The most common phenolic acids identified from P. hydropiper were sinapic, salicylic+vanillic and ferulic acid presented in all the fractions. In addition, salicylic+vanillic, tannic+gallic, sinapic, ferulic and p-coumaric acid seemed to be important phenolic compounds in terms of quantity. However, salicylic+vanillic acids were the unique phenolic acids occurred in all the fractions of P. aviculare. The others such as tannic+gallic, sinapic, ferulic, p-coumaric acid, p-cresol and catechol present in large amount appeared also the important phenolic substances influencing allelopathic effects of P. aviculare. Linolenic acid and oxalic acid were the major fatty and organic acids in both plant species, presented in 2.38mg/g and 20.588mg/g in P. hydropiper, 3.70mg/g and 14.288mg/g in P. aviculare, respectively, which seem to be exhibiting allelopathic effects of these plants. Total alkaloids were presented in low amount such as 0.20% in P. hydropiper arid 0.22% in P. aviculare which may not be important elements. Pet. ether extracts were 2.42% in P. hydropiper and 1.65% in P. aviculare, which exhibit another potential for allelopathic effects that need further investigation. Various authentic phenolic compounds at different concentrations inhibited the germination of lettuce seed, indicating that the phenolic substances identified here may be directly related to biologically active substance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.255-261
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• 1988

For the purpose of fermentation control and edible period extension of lower salted Kimchi, the contents and compositions of pectic substances in Kimchi, by adding 2 percent salt and 0.4 percent sodium malate buffer(SMB), fermented at $20^{\circ}C$ were investigated. Edible period of SMB added chinese cabbage Kimchi was extended 40 hrs compared to that of control (added 2.5% salt) with good flavor, texture and freshness. The contents of alcohol insoluble solid(AIS) and protopectin(PP) of control were more decrensed during fermentation than those of SMB added Kimchi. But, the contents of pectic adid(PA) and water soluble pectin(WSP) of control were more increased during fermentation than those of SMB added Kimchi. Hexose and pentose from hemicellulose in control, PP and PA respectively, were more decreased during fermentation than those in SMB added Kimchi. Lower polarity and higher molecular weight PP was eluted and higher polarity and lower molecular weight PP was decreased considerably in control compared to those in SMB added Kimchi during fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.621-628
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• 2002

Effect of the thickness of packaging film on the ripening of mature-green mume (Prunus mume Sieb. et Zucc) fruit was investigated by measuring physicochemical changes of the fruit during storage. Fruits were packaged using low density polyethylene (LDPE) films with thicknesses of 20, 30, and 40$\mu$m and stored at the room temperature. The physicochemical properties such as contents of various pectic substances, molecular weight distribution of soluble pectic substances, and surface image of the fruit were determined during storage of 8 days. In general, regardless of the thickness of the films applied, a content of water-soluble pectin (WSP) in the fruit was increased during storage, but both contents of HCI- soluble pectin (HSP), and Ca and Mg in total alcohol-insoluble solids were decreased. Sephacryl S-300 gel filtration study revealed that fractions of high molecular weight HSP and WSP decomposed into lower molecular weight pectins during storage. The scanning electronic microscope also identified a significant structural change of the fruit skin over the storage time. It could be concluded from the results that fruits packaged with LDPE 30${\mu}{\textrm}{m}$ film maintained the highest physicochemical quality of green mume fruit during storage.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.65-70
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• 1986

Total pectin content of Korean apple varieties at optimum harvest time was deter-mined by carbazole reaction method and pectin fraction content in each variety was also determined. Properties of pectin extracted ty 2a Sodium hexa metaphesphate were compared with commercial pectin. Among apple varieties, pectin contents varied in the range of 0.26-0.48％ on fresh basis and 1.76-4. 0% on dry basis. Ball's was the highest and then high in order of Spur early blaze, Golden delicious, Fuji. , Jonathan. In each pectin fraction, soluble pectin fractions in Rall's was the lowest and in both Spur early blaze and Golden Delicious were highest but insoluble fractions in the latter were lowest. Thub the changes in poetic substances in Spur early blaze and Golden delicious seem to he occurred: during early ripening. In the analysis of properties of isolated pectin, ash, anhydrogalacturonic arid7(AUA) content and methoxyl content were different among apple varieties. Ash and methoxyl content in all isolated pectin were higher and AUA content lower than in commercial pectin. Degree of esterification (DE) in all apple varieties were above 70％.