• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.905-910
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• 2004

This study was carried out to observe the change of oriental melon juice quality during manufacture by heating condition and enzyme treatment. To use over-production oriental melon effectively, oriental melon juice was prepared with change of heating temperature and heating time. The heating conditions for minimum filtration time were 98.57$^{\circ}C$ and 11.29 min. The optimum conditions Predicted for separation ratio of clear solution, filtration time and browning color intensity of oriental melon juice were 98$^{\circ}C$, 13 min. In the pectin-degrading enzyme treatment test, turbidity showed minimum value in 4.40 mg％(pectin-degrading enzyme content)， 39.72 mg％ (gelatin content) and 24.09 min (treatment time)．Browning color intensity showed minimum value in 9.33 mg％ (pectin-degrading enzyme content)，44.70 mg％ (gelatin content) and 115.56 min (treatment time). The optimum conditions predicted for turbidity and browning color intensity of oriental melon concentration Juice were 6.6 mg％ (pectin-degrading enzyme content), 33.6 mg％ (gelatin content) and 70 min (treatment time).

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.242-246
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• 1995

This paper was carried out to investigate changes in cell wall, cell wall polysaccharides, pectic substances extracted from cell wall of persimmon fruits treated with polygalacturonase and $\beta$-galactosidase in vitro. Degrading degree of cell wall treated with cell wall-degrading enzymes were higher in order polygalacturonase, polygalacturonase+$\beta$-galactosidase and $\beta$-galactosidase. Contents of soluble pectic substances in cell wall treated with cell wall-degrading enzymes showed as the same order as degrading degree of cell wall, while contents of insoluble pectin lower. Contents of versene-soluble pectin and total pectic substance were not affected by cell wall-degrading enzymes. Contents of uronic acid and hexose in soluble material isolated from cell wall treated with polygalacturonase and mixed enzyme were higher than those of untreatment and $\beta$-galactosidase treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.247-253
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• 1995

This paper was performed to investigate the changes of non-cellulosic neutral sugars composition in cell wall of persimmon fruit by treatment of cell wall degrading enzyme in vitro. Rhamnose, xylose and galactose in cell wall by polygalacturonase treatment, arabinose, galactose and rhamnose in cell wall by mixed enzyme treatment and arabinose and galactose in cell wall by ${\beta}-galactosidase$ treatment decreased, respectively. Noncellulosic neutral sugars of pectins extracted cell wall by enzyme treatments decreased and those by polygalacturonase treatment decreased remarkably. Rhamnose, arabinose and xylose in hemicellulose I of cell wall by polygalacturonase treatment were higher than those of untreated, and rhamnose and xylose in that by ${\beta}-galactosidase$ treatment were higher but arabinose, mnnose and galactose decreased. Xylose, mannose and glucose in that by mixed enzyme treatment were higher than those of untreatment and arabinose and galactose decreased. Contents of total non-cellulosic neutral sugars in hemicellulose of untreatment, and contents xylose, and glucose in hemicellulose II of cell wall by polygalacturonase treatmet decreased but those of other treatments were not changed.

• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.357-362
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• 1994

Chitinases and $\beta$-1,3-glucanases are believed to be important in defending plane against pathogens. Here, we investigated the expression of chitinase(s) in Arabidopsis thaliana cell suspension culture system in response to ethephon (2-chloroethyl phosphonic acid) which produces ethylene or a microbial elicitor, a bacterial pectin-degrading enzyme, $\beta$-1, 4-endopolygalactronic acid Iyase (PGA Iyase), treatment. Chitinase activity was measured either by radio chemical assay using $^3$H-labeled regenerated chitin as substrate or western blot analysis using antibody raised against tobacro chitinase(S). With 1 mg/mL of ethephon or 100 m units/mL of elicitor treatment, maximum levels of activity were reached after 48h. We also investigated distribution of chitinase activity in seedlings, leaves, and root of A. thaliana and found that root have the highest chitinase activity.