• Title/Summary/Keyword: barley $\alpha$-amylase 2

Search Result 40, Processing Time 0.027 seconds

Kinetic Studies on Amylases from Barley and Wheat Malt (보리와 밀 맥아 Amylases의 반응속도론적 연구)

  • 김영휘;조정일
    • Journal of Food Hygiene and Safety
    • /
    • v.6 no.3
    • /
    • pp.127-131
    • /
    • 1991
  • ${\alpha}-amylase\;and\;{\beta}-amylase$ were extracted from barley and wheat malt, respectively. Their kinetic parameters on gultinous and nonglutinous rice starch were examined. During the germination of barley and wheat, the increaments of ATP levels were significant after 2-day germination and the levels were reduced after 5 days. The dry weights were decreased after 3 days. The activities of amylases were the highest for 6 days in the barley and wheat malt. As for ${\alpha}-amylase$, that the substrate affinity of barley malt on nonglutionous rice starch was greater than other cases. The $V_{max}$ values of ${\alpha}-amylase$ from wheat malt on either type of rice starch showed high, and from barley malt on nonglutinous rice starch were high. The ${\beta}-amylse$ from barley malt showed high substrate affinity on the glutinous rice starch, and $V_{max}$ value of the enzyme from wheat malt on glutinous rice starch was higher than other. The substrate efficiency ($V_{max}/K_{m}$) of ${\beta}-amylase$ on the non glutinous rice strach was better than other cases.

  • PDF

Screening and Characterization of $\alpha$-Amylase Inhibitors from Cereals and Legumes in Korea (한국산 곡류와 두류 중 $\alpha$-Amylase 저해물질의 검색 및 특성)

  • Sim, Gi-Hwan;Bae, Yeong-Il;Mun, Ju-Seok
    • Food Science and Preservation
    • /
    • v.1 no.2
    • /
    • pp.117-124
    • /
    • 1994
  • To investigate characterization of the ${\alpha}$-amylase inhibitors from cereals and legumes produced in Korea, inhibitory activities against ${\alpha}$-amylase with the inhibitor from barley(Hordeum vulgare), wheat(Triticum aestivun), black bean(Glycine max), bean(Cajanus cajon) and pea(Pisum sativum) were measured. Among the samples tested, inhibitors from naked barley and black bean(sabong) which showed the highest inhibitor activities of cereals and legumes, respectively, were characterized according to treatment condition. The results obtained were summarized as follows. During the germination of naked barley and black bean, ${\alpha}$-amylase activities were gradually increased but inhibitory activities against ${\alpha}$-amylases were decreased. Both activities were gradually decreased when naked barley and black bean were stored. More than 50% of activities of the inhibitors from naked barley and black bean were remained at 100$^{\circ}C$ for 15 min and 20 min, respectively, indicating that the inhibitor from black bean was more stable to heat than that of barley.

  • PDF

Effects of Dimethipin on α-amylase Activity of Barley Seeds (보리 종자의 α-아밀라아제 활성에 미치는 Dimethipin의 영향)

  • Lee, Joon-Sang
    • Journal of Environmental Science International
    • /
    • v.16 no.4
    • /
    • pp.409-414
    • /
    • 2007
  • Effects of dimethipin on ${\alpha}$-amylase activity of barley seeds were investigated. In the treatments of $1{\mu}M\;and\;10{\mu}M$ dimethipin, the indexes of germination were reduced to 17% and 24 % respectively. After seed germination, dimethipin was added to germinated seedlings and then the seedlings were kept to measure seedling length under illumination for 7 days. In control, the length of seedling was 5.7 cm, but in the treatments of $1{\mu}M$ dimethipin and $10{\mu}M$ dimethipin, seedling lengths were 5.5 cm and 1.2 cm respectively. In the relationship between dimethipin concentrations and ${\alpha}$-amylase activities, there was a linear curve. The more dimethipin was added to the seeds, the more ${\alpha}$-amylase activities were inhibited. In the treatments of $1{\mu}M$ dimethipin and $10{\mu}M$ dimethipin, ${\alpha}$-amylase activities were reduced to 33% and 71% respectively. Dimethipin also inhibited ${\alpha}$-amylase activities increased by gibberellin and the content of soluble protein. Therefore, it could be suggested that dimethipin might inhibit directly the activities of hydrolysis enzymes including ${\alpha}$-amylase or the expression of ${\alpha}$-amylase genes as germination and seedling growth were severely disturbed.

The Physicochemical Properties of $\alpha$-Amylase Inhibitors from Black Bean and Naked Barey in Korea (한국산 검정콩 및 쌀보리 $\alpha$-Amylase 저해물질의 이화학적 특성)

  • 심기환;문주석;배영일
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.27 no.3
    • /
    • pp.367-375
    • /
    • 1998
  • The physicochemical properties of the $\alpha$-amylase inhibitors from black bean and naked barley is Korea were investigated. Preincubation time for maximum inhibition was 30min and no activity change was seen after that time. Optimum pH of the $\alpha$-amylase inhibitors from the black bean and naked barley was pH 7.0 and the inhibitory activities were stable in the range of pH 6.0~8.0 in both phosphate and Tris-HCI buffer solutions. Both inhibitors maintained more than 50% of activity after incubation for 17 min at 7$0^{\circ}C$. The inhibitors from the black bean and naked barley maintained more than 50% of activities after treatment for 40 min and 30 min with pepsin, and 30 min and 50 min with trypsin, respectively. Both inhibitors functioned via a noncompetitive mechanism and were active against porcine pancreatic and human salivary $\alpha$-amylases. The activities of both inhibitors were linear for the ionic stength ranging from 0 to 0.9. The addition of 70 mM maltose to the reaction mixture caused a maximum increase in the relative activities of both inhibitors, but it did not affect the dissociation of the EI complex. The activities of both inhibitors were significantly enhanced by adding 1mM of K+ or Mg2+.

  • PDF

Stabilization of Amylolytic Enzymes by Modification with Periodate-Oxidized Soluble Starch (과요오드산 산화전분 변형에 의한 아밀라아제의 안정화)

  • ;Tri;Kazuo Ito;Masaru Iizuka;Noshi Minamiura
    • The Korean Journal of Food And Nutrition
    • /
    • v.11 no.5
    • /
    • pp.561-564
    • /
    • 1998
  • The stabilizatio of amaylolytic enzyme such as $\beta$-amylase of barley, $\beta$-amylase of wheat, $\beta$-amylase of sweet potato, $\alpha$-amylase of Bacillus licheniformis, $\alpha$-amylase of Aspergillus sp. and $\alpha$-glucosidase of Aspergillus awamori was attained by modification with periodate-oxidized soluble starch. The pH stability of modified enzyme was increased at pH 9 for $\beta$-amylase of sweet potato, pH 3~5 and 8~11 for $\beta$-amylase of barley, pH 2~3 and 7~12 for $\beta$-amylase of wheat and pH 6 for $\alpha$-glucosidase of Aspergillus awamori. Thermal stability increased 17.6% for $\alpha$-amylase of Aspergillus sp. at 6$0^{\circ}C$ for 10min, 30% for $\alpha$-amylase of Bacillus licheniformis at 10$0^{\circ}C$ for 5min and 4.5% for $\alpha$-amylase of sweet potato at 6$0^{\circ}C$ for 10min compared with those of native enzymes.

  • PDF

Stabilization of Barley $\beta$-Amylase by Modification with $IO_4$-Oxidized Starch ($IO_4$-산화전분 변형에 의한 보리 $\beta$-Amylase의 안정성 증가)

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

  • PDF

Effect of Dimethipin on the ${\alpha}-amylase$ Induction in Barley Seeds (보리종자에서 ${\alpha}-amylase$ 유도에 미치는 Dimethipin의 영향)

  • 전방욱
    • Journal of Plant Biology
    • /
    • v.34 no.2
    • /
    • pp.159-163
    • /
    • 1991
  • The effect of dimethipin, one of the synthesized plant growth regulators, on the gibberellic acid-induced a-amylase activity in the barley de-embryonated seed system was investigated in order to elucidate the possible action mechanism of dimethipin. Dimethipin markedly inhibited the increase of mRNA and protein content, and a-amylase activity induced by gibberellic acid. The inhibitory effects were gradually decreased as the time interval between gibberellic acid treatment and dimethipin addition was made larger. Dimethipin inhibited the increase of mRNA content when added within 18 h from gibberellic acid treatment; however, it inhibited the increase of soluble protein content and a-amylase activity even added after 18 h from the treatment. These results suggest the possibility that dimethipin inhibit both mRNA synthesis and a-amylase protein synthesis.thesis.

  • PDF

Activities of Hydrolytic Enzymes in Barley Malts Prepared under Different Germination Conditions (발아조건별 당화용 엿기름의 분해효소 활성도)

  • Mok, Chul-Kyoon;Lee, Young-Tack
    • Applied Biological Chemistry
    • /
    • v.42 no.4
    • /
    • pp.324-329
    • /
    • 1999
  • Barley malts were prepared at 15, 18 and $21^{\circ}C$ for $3{\sim}6$ days, and assayed for ${\beta}-glucanase$, ${\alpha}-amylase$ and ${\beta}-amylase$ activities. ${\beta}-Glucanase$ activity increased markedly during earley germination and reached maximum at the 6th day of germination. ${\beta}-Glucanase$ activity in six-rowed barley malt was much higher than that in two-rowed malt. ${\beta}-Glucanase$ activity was associated with reduction in ${\beta}-glucan$ content during germination. ${\beta}-amylase$ activity was also considerably higher in two-rowed barley, and increased continuously during 6-day germination. ${\beta}-Amylase$ activity was the lowest at $15^{\circ}C$, the highest at $18^{\circ}C$, and intermediate at $21^{\circ}C$ of germination temperature. Considerable amount of ${\beta}-amylase$ was detected in ungerminated raw barley, and this enzymatic activity tended to increase during 6-day germination. Diastatic power, measure of starch-saccharifying enzyme, in six-rowed malt was $1.4{\sim}1.6$ fold higher than in two-rowed malt. Germination at $18^{\circ}C$ for $5{\sim}6$ days was suggested to be the optimum condition for manufacturing good quality malts, in terms of enhanced starch-degrading enzymatic activity.

  • PDF

A Study on Amylase Activities During Germination of Maize Seeds (옥수수의 발아과정중(發芽過程中) AMYLASE활성(活性))

  • Choi, Kook-Chi
    • Applied Biological Chemistry
    • /
    • v.27 no.2
    • /
    • pp.107-111
    • /
    • 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.

  • PDF

Effects of Red light on ${\alpha}-Amylase$ isozymes of the Germinated Barley (Hordeum distichum L.) (맥아의 ${\alpha}-Amylase$ isozyme에 미치는 Red Light의 영향)

  • Kim, Jin-Gu;Shin, Seung-Ryeul;Kim, Kwang-Soo;Shon, Tae-Hwa
    • Applied Biological Chemistry
    • /
    • v.31 no.4
    • /
    • pp.351-355
    • /
    • 1988
  • This study carried out to change ${\alpha}-amylase$ activity and isozymes in barley during germination in the dark and red light. The specific activity of ${\alpha}-amylase$ increased during the germination in the dark, giving 355.0 and 523.7 units/mg protein at 3 and 5 days, and the activity was increased by the red light up to 48 and 15% at 3 and 5 days of germination, respectively. The ratio of ${\alpha}-amylase$ I and II was approximately 95 : 5 at both 3 and 5 days of germination in the dark while the different ratio was found by the red light i.e. 60 : 40 and 90 : 10 at 3 and 5 days of germination, respectively.

  • PDF