• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.62-67
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• 1999

Periodate-oxidized soluble starch and maltohexaose, maltotetraose, maltose, and glyceraldehyde reacted with sweet potato ${\beta}-amylase$, wheat ${\beta}-amylase$, aldolase, bovine serum albumin, catalase, carboxypeptidase, ferritin and pronase. Electrophoretical mobility of modified proteins was different from that of native proteins, and modified proteins were stained with periodic acid-Schiff while native proteins did not stain. This results means that oxidized sugars attached on proteins. This bond is based on the Schiffs base between CHO group of oxidized sugar and ${\varepsilon}-NH_2$ group of lysine of protein. There is no changed UV absorption spectrum of sweet potato ${\beta}-amylase$ modified with oxidized soluble starch, in comparison with native enzyme.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.522-534
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• 1996

The present study was conducted to investigate quality characteristics of Nochi made with malted barley flour with (Cl) and without hull (C2), comparing with Nochi that was treated with different sources of commercial amylases. There was higher level of moisture content (18.4%) in Nochi treated with fungal ${\alpha}$-amylase (FU) comparing with the other Nochi samples. However, Nochi that was treated with bacterial ${\alpha}$-amylase and ${\beta}$-amylase (BA-${\beta}$) had the lowest level of moisture content (11.2%). Nochi samples which were treated with thermostable ${\alpha}$-amylase and fungal ${\alpha}$-amylase(TE-FU) were different from traditional Nochi samples in mechanical characteristics. According to the results of sensory evaluation, Cl was similar to C2 except in cohesiveness and malt flavor. TE-FU and Bh-${\beta}$ were not different from traditional Nochi in cohesiveness, sweetness and overall desirability.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.107-111
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• 1984

Changes of starch, soluble sugar and activities of amylase in germinating maize seeds were studied with comparison of germinating barley seeds. The starch in the endosperm was degraded slowly during the course of germination, and starch degradation of maize seeds compared with barley seed was found after 2 or 4 days of seed germination. There was a transient decline of soluble sugar come-its in ungerminated seed at early stages, followed by the rapid increase which concided with the degradation of starch. Activities of amylases were increased with the progress of germination, and maximum activities were founded after 8 days of seed germination. The higher activities of ${\alpha}$- and ${\beta}$-amylase were found at Hwang-ok maize and barley, respectively.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.253-258
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• 1996

Stabilities of sweets potato f-amylase on various reagents were studied. The enzyme was stabilized by bovine serum albumin, Triton X-100 and 2-mercaptoethanol of 0.04%. Among them, bovine serum albumin was the most effective. And enzyme stability was increased by using the deairated solution. The enzyme activity was remained 0% in the absence of glycerol, 25% in the presence of 20% glycerol and 50% in the presence of 40% glycerol at 37$^{\circ}C$, for 15 hours in pH 11. SDS inhibited the enzyme, and 2-mercaptoethanol and dithiothreitol stabilized it.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.359-365
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• 2015

The purpose of this study was to investigate the contents of sugars and ${\alpha}$-amylase and ${\beta}$-amylase activities in 98 specimen with enzyme foods and enzyme-shaped foods (the other processed foods, beverage bases, fermented drinks, liquid teas). The ${\alpha}$-amylase activity in enzyme foods and the other processed foods were ranged 4.9~53,854.6 U/g and 2.9~1,182.7 U/g, respectively, there was a big difference in the same type. The ${\alpha}$-amylase activity of the fermented products (beverage bases, fermented drinks, liquid teas) were ranged 0.1~1.7 U/g. The average of ${\beta}$-amylase activity in enzyme foods, the other processed foods, the fermented products were found 126.0 U/g, 5.6 U/g and 10.5 U/g, respectively, enzyme-shaped foods were a lot lower than enzyme foods. Total contents of sugars were average 22.4 g/100 g in enzyme foods, 14.8 g/100 g in the other processed foods, 46.9 g/100 g in beverage bases, 41.1 g/100 g in fermented drinks, 39.5 g/100 g in liquid teas, total contents of sugars appeared high amount in the fermented products. Correlations between ${\alpha}$-amylase activity and lactose content was statistically significant in enzyme foods (r = 0.644) and it was strong in the other processed foods (r = 0.903). Correlations between ${\beta}$-amylase activity and lactose content was statistically significant in enzyme foods (r = 0.648) and it was strong in the other processed foods (r = 0.757). There was a significant relationship between ${\alpha}$-amylase and ${\beta}$-amylase activities in enzyme foods and the other processed foods (r = 0.869, r = 0.760). That is, it was found that also the proportional relationship established among the ${\alpha}$-amylase activity, ${\beta}$-amylase activity.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.159-164
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• 1998

pH stability of sweet potato $\beta$-amylase modified with IO4-oxidized soluble starch was increased at pH 3, 5~9 and 11. And optimum pH was 3 and 5 for modification. Thermal stability of the enzyme modified with IO4-oxidized soluble starch was increased at 6$0^{\circ}C$ for 15 min. pH stability of barley $\beta$-amylase modified with IO4-oxidized soluble starch was increased at 3~4 and 8~11, and more increased at pH 3 and 8~11 in the presence of $\alpha$-cyclodextrin.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.342-347
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• 2000

The stabilization of barley $\beta$-amylase(Biozyme ML, Amano) was attained by modification with periodate-oxidized soluble starch. The specific activities of modified enzyme at pH 9.7 and pH 8.0 were 42% and 92%, respectively, compared with that of native enzyme. The pH stability of modified enzyme was increased at pH 2~5 and 7~12 in the presence of $\alpha$-cyclodextrin( $\alpha$ -CD) compared wish that of native enzyme. Thermal stability of the modified enzyme was increased. After treatment at 6$0^{\circ}C$ for 10min. the activity remained 8% for the enzyme modified at pH 8.0 in the presence of $\alpha$-CD, 4.5% for the native enzyme. The native enzyme and modified enzyme showed two peak in HPLC. The molecular weight of the modified enzyme was slightly increased in HPLC analysis.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.348-352
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• 2000

The stabilization of wheat $\beta$-amylase( Himaltosin GL, Hankyu-Bio) was attained by modification wish periodate-oxidized soluble starch. The specific activities of modified enzyme at pH 9.7 and pH 8.0 were 17% and 96%, respectively, compared with that of native enzyme. The pH stability of modified enzyme was increased at pH 2~5 and 6~12 in the presence of $\alpha$-cyclodextrin( $\alpha$-CD) compared with that of native enzyme, and optimum pH of the enzyme was changed from pH 5.0 to pH 7.0 by the modification. Thermal stability of the modified enzyme was increased. After treatment at 6$0^{\circ}C$ for 10min, the activity remained 8% for the enzyme modified at pH 8.0 in the presence of $\alpha$-CD and tested in the presence of $\alpha$-CD, 5% for the native enzyme. The native enzyme and modified enzyme showed one peak in HPLC. The molecular weight of the modified enzyme was slightly increased in HPLC analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.123-127
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• 1969

The studies were conducted to know the relationship between $\beta$-amlyase activities and hardiness for the germinated seedlings of, winter wheat varieties which were classified with eye estimated cold resistance in field as, susceptible, moderate and resistant. These varieties were tested in continued five days from germination in four replicated split plot design. For the measurement of $\beta$-amylase, improved A. K. Balls method (2) was employed. Result obtained will be summarized as follows. 1. Tested varieties showed highly significant differences in $\beta$-amylase activity, while no differences were obtained between dates after germination. 2. Winter hardy varieties, Yukseung ＃3, Chin Kwang and Suwon＃85 showed higher amylase activities than the moderate hardy varieties, Jukdalma, Kangdosinryuk and Norin ＃4, while lower activities were measured in susceptible varieties, Norin ＃6, Kangdo and Norin＃12. 3. With measurement of $\beta$-amylase activity, rurther detail classification to cold resistance is seemed available than eye-estimating in the field condition. 4. In accordance with testing dates, amylase activities were not so clear on 1st, 2nd, 4th and 5th days from germination, while clear differences were found on 3rd day from germination. 5. Amylase activity obtained on 3rd day after germination is considered easy and effective method to estimate cold resistance of wheat varieties with a classification standard.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.403-409
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• 1997

To obtain information on the accumulation of (1-3, 1-4)-$\beta$-glucans during kernel maturation, (1-3, 1-4)-$\beta$-glucan contents and (1-3, 1-4)-$\beta$-glucanase activities were determined in developing kernels of the two Korean cooking barley varieties, Neulssalbori and Saessalbori. (1-3, 1-4)-$\beta$-Glucan contents in kernels at 5 and 10 days after anthesis(DAA) were very low and the contents increased rapidly in kernels at 15 to 25 DAA. (1-3, 1-4)-$\beta$-Glucan content in kernels at harvest was about 3.5 to 4% of kernel dry matter. (1-3, 1-4)-$\beta$-Glucanase activities were relatively higher in younger kernels but the levels of the activity were very low compared with those in germinating kernels. A significant negative correlation was observed between (1-3, 1-4)-$\beta$-glucan contents and (1-3, 1-4)-$\beta$-glucanase activities. Low levels of (1-3, 1-4)-$\beta$-glucanase activites in kernels at 15 to 30 DAA, however, may indicate that (1-3, 1-4)-$\beta$-glucanases have little effect on the final content of (1-3, 1-4)-$\beta$-glucans in barley kernels. Starch contents and $\alpha$-amylase activities were also determined in developing barley kernels. Starch contents increased rapidly as kernels matured and the content at harvest was about 60% of kernel dry matter. Relativley higher levels of $\alpha$-amylase activities in kernels at the earlier developmental stage decreased rapidly as kernels matured.