• The Korean Journal of Food And Nutrition
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• v.3 no.1
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• pp.57-68
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• 1990

In order to obtain the fundamental informations on cellulase of Trichoderma viride QM 9414 for its production and utilization, some physico-chemical properties of the enzyme were reviewed. When T. viride QM 9414 was cultured on wheat bran medium, filter paper-disintegrating and carboxymethyl cellulose-saccharifying activity were increased with the cell growth, and thereafter CMC-saccharifying activity was kept on almost the same leved while filter-paper disintegrating activity was decreased sharply. And B-glucosidase was formed maximally on the late stationary phase of growth. The crude cellulase of cell-free extracts was purified by (NH4)2SO4 fractionation, Sephadex-G 200 column chromatography and DEAE Sephadex A-50 column chromatography. Filter paper-disintegrating, CMC-saccharifying and B-glucosidase activity were purified 10-fold, 47-fold and 38-fold, respectively. The crude enzyme was proved to be a complex of three different enzyme proteins which were showing filter paper-disintegrating, CMC-saccharifying and B-glucosidase activity. The optimal pH of the three enzyme components was alike pH 4.0, and the optimal temperature for CMC-saccharifying, filter paper-disintegrating and B-glucosidase activity were 4$0^{\circ}C$, 45$^{\circ}C$ and 5$0^{\circ}C$ respectively. The Km and Vmax values of CMC saccharifying activity for CMC were 0.485% and 3.10, and the Km and Vmax vallues of B-glucosidase for PNPG were 0.944$\times$10-3M and 0.097, respectively. The Km and Vmax values of filter paper-disintegrating activity for Avicel were determined to be 0.09% and 0.178, respectively. B-Glucosidase activity was competitively inhibited by glucose, and the Ki value for this enzyme was 3.54$\times$10-3M, CMC saccharifying activity was found to be greatly inhibited by cellobiose.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.166-185
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• 1983

Aspergillus niger IFO 8541 (NRRL 3112) was investigated through a series of UV rays and N-Methyl-N'-Nitro-N-Nitrosoguanidine (NTG) treatments to induce mutants that produce highly active raw starch saccharifying enzyme, and two mutants with strong enzymatic productivity were obtained. The mutants obtained were investigated for their fungal characters, condition of enzyme production, and other activities. Furthermore, the raw starch saccharifying enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were summarized as follows; 1. The color of conidial head of UV-46 mutant obtained from UV rays treatment was changed to tan type and the gelatinated starch saccharifying enzyme productivity and the raw starch saccharifying enzyme productivity increased up to twice and 1.8 times compared to the productivities of original Aspergillus niger IFO 8541 cultured on the wheat bran, respectively. 2. The conidial head color of NG-41 mutant obtained from NTG treatment became lighter than that of parent strain. The gelatinated starch saccharifying enzyme productivity and raw starch saccharifying enzyme productivity increased about 1.8 times, and twice over the Aspergillus niger IFO 8541 parent strain cultured on wheat bran, respectively. The productivity of ${\alpha}$-amylase increased about 3 times more than the parent strain. 3. Two peaks of glucoanlylase and a peak of ${\alpha}$-amylase were obtained when enzyme solution of mutants and parent strain were passed through DEAE-Sephadex A-50 column chromatography. Glucoamylase I showed only gelatinated starch saccharifying enzyme activity. However, glucoamylase II (raw starch saccharifying enzyme) showed both raw starch saccharifying enzyme activity and gelatinated starch saccharifying enzyme activity. 4. Mutant, UV-46 was strengthened in glucoamylase II productivity and mutant NG-41 was strengthened in ${\alpha}$-amylase productivity. 5. Glucoamylase II of mutants and parent strain were appeared to have the same enzymatic properties. 6. Glucoamylase II of mutants and parent strain were recognized as simple enzyme through electrophoresis. 7. The glucoamylase II crystallized showed rhombic board type. 8. The molecular weight, isoelectric point, optimum pH, and optimum temperature of the glucoamylase II crystallized were estimated as 76,000, 3.4, 3.5 and $60^{\circ}C$, respectively.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.547-552
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• 1990

We have been searching microorganisms which produce highly active raw starch saccharifying enzyme and also have a good cultivation characters in submerged culture. About 170 strains of molds isolated from soil and compost were tested for their amylase productivity on plate contained 2% raw corn meal. Thirty-four strains out of 170 strains produced clearance on the plates, and were tested for their raw starch saccharifying activity. Then, 4 strains which had shown relatively high levels of saccharifying activity were selected. Among them, Strain No. 55 was found to have highest level of raw starch saccharifying activity, and selected for the further studies. In this paper, the morphological, physiological and cultural characteristics of Strain No. 55 were described. Based on the results obtained in these experiments, Strain No. 55 was identified to be a similar species to Aspergillus niger.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.408-413
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• 1987

Microorganisms capable of degrading the raw naked barley were isolated from soil, and the amylase productivity of each strain was examined on plate contained 2％ raw naked barley. Of the fungi and actinomycetes tested, 71 strains were subjected to subsequent testing for amylase production, and 4 strains were selected as potent amylase producers. Among them, Strain No. 281 produced the most potent raw naked barley saccharifying enzyme, and was identified as genus Rhizopus from morphological and physiological studies. The ratio of raw starch saccharifying activity (RDA) of the crude enzyme derived from the Rhizopus sp. No. 281 was showed 2-3 fold higher than that of commercial enzyme when the raw naked barley was used as the substrate. In the case of uncooked alcohol fermentation using Rhizopus sp. No. 281 glucoamylase preparation, the alcohol yield of the broth was 2％ higher than that of the commercial enzyme.

• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.140-146
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• 1991

Mutation experiments were performed to select the mutant of Aspergillus niger 55, which had lost almost all the ability to produce transglucosidases but retained that of high productivity of raw meal saccharifying enzyme, by means of successive induction with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), ultraviolet(UV) light, and ${\gamma}$-rays. Also, we used the mutant enrichment techniques, such as liquid culture-filtration procedure and differential heat sensitivity of conidia, in order to increase the possibility of obtaining a mutant. The glucoamylase productivity of mutant PFST-38 was 11 times higher than that of the parent strain. The mutant PFST-38 was morphologically identical to the parent strain, except for the size of conidia, the tendency to form conidia and the lenght of conidiophore. Asp. niger mutant PFST-38 apeared to be useful for the submerged production of the raw corn meal saccharifying enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.417-421
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• 1997

Quality of Sikhe, the Korean conventional rice beverage depended on the characteristics of saccharifying activities of various amylases, intrinsic flavour, budding rate and so on. To improve the quality of Sikhe, characteristics of malt produced with wheat, covered barley and naked barley were evaluated. The germination rate of wheat was 82%, but those of naked and covered barley were 69% and 56% for 6 days, respectively. Malt prepared from germinated grains with 1.5~2.0 times length of buds had the highest saccharifying power. when the extraction of enzyme and reducing sugar was carried out at 5$0^{\circ}C$ for 4 hr, saccarifying power and reducing sugar contents were the highest. Malt of wheat had the highest saccharifying power. Malt of naked barley had higher saccharifying power than that of covered barley. The amylase types of wheat, covered barley and naked barley were similar to $\beta$-amylase.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.702-706
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• 2006

The aim of this study was to identify the onuses of abnormal precipitation in buckwheat extracts and to suggest the preventive solutions. Abnormal precipitation was formed by the coagulations of small round droplets, and increased when poor quality or old buckwheat used. It was found that, unlike poor quality buckwheat, extracts made from fresh buckwheat showed almost no saccharifying enzyme activity and a lower number of microorganisms. The addition of branched starch to the extracts restricted the occurrence of abnormal precipitation and microorganisms and imparted stability to the extracts.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.169-174
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• 1987

The studies on the screening and properties of Raw Starch Saccharifying Microorganism were as follows;Apotent mold strain was selected and screened to digest raw starch, which was classified as a strain of Aspergillus sp. SN-871. The crude enzyme production was maximized when grown on wheat bran media for 5 days at $30^{\circ}C$ and pH 4.0. The stable range of pH was 2 to 5.

• Applied Biological Chemistry
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• v.3
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• pp.9-15
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• 1962

1) Among 8 strains of Rhizopus and 7 of Aspergillus species investigated for their producibility of saccharifying amylase, Rhizopus delemar ND 1 and Aspergillus usamii mut. shirousamii were selected as having high saccharifying activity. 2). Since Rh. delemar ND 1 shows high saccharifying activity and slight transglucosidase activity, it likely seems suitable for the production of starch-sugar by enzymic saccharification. Asp. usamii mut. shirousamii exerts low saccharifying but moderate transglucesidase activity and is considered to be usable in producing sugar-syrup with particular flavor and taste. 3). Using the saccharogenic enzyme from Rh. delemar ND 1, a prelimimary trial was done to obtain purified glucose powders.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.698-705
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• 2016

This study aimed to evaluate the quality characteristics of Gastrodia elata Blume fermented by lactic acid bacteria after saccharifying by 3 methods including enzyme, malt, and rice-nuruk. The lactic acid bacteria (LAB), Pediococcus inopinatus BK-3, isolated from kimchi could reduce the unpleasant taste and odor of Gastrodia elata Blume. The total acidity value of Gastrodia elata fermented by LAB on the malt and rice-nuruk extract solution for 3 days was 2.23% and 2.33%, respectively. After saccharification by malt and rice-nuruk extract solution for 3 days, the viable cell number of fermented Gastrodia elata was 9.14 log cfu/mL and 9.27 log cfu/mL, respectively. The total acidity values were increased above 3.35% by malt and rice-nuruk extract solution for 8 days. Thus, the viable cell number was the highest by malt and rice-nuruk extract solution fermentation for 3 days. The amino acid content of Gastrodia elata fermented by LAB after saccharification by malt extract solution was higher than that of other saccharifying methods. The free sugar content and p-hydroxybenzyl derivatives induced by the enzyme method were higher than those of other saccharifying methods. The overall acceptability was the highest at 4.2 point in Gastrodia elata fermented by malt extract solution.