کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4565556 | 1330987 | 2007 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Extraction, thermal stability and kinetic behavior of pectinmethylesterase from hawthorn (Crataegus pubescens) fruit
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
دانش تغذیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Extraction, thermal stability and kinetic behavior of pectinmethylesterase from hawthorn (Crataegus pubescens) fruit Extraction, thermal stability and kinetic behavior of pectinmethylesterase from hawthorn (Crataegus pubescens) fruit](/preview/png/4565556.png)
چکیده انگلیسی
Pectinmethylesterase (PME) extracted from hawthorn (Crataegus pubescens) fruit was evaluated for its thermal stability and kinetic behavior. The enzyme extraction process was established after studying different NaCl concentrations (0.5-3.0 moles/L). A maximum PME extraction of 51.61 units/mg protein was obtained using 2 moles/L NaCl. Kinetic parameters (Km and Vmax) were determined using a commercial citrus pectin and C. pubescens pectin as substrates. The effects of NaCl concentration, pH and temperature on PME activity were investigated. PME showed higher affinity for C. pubescens pectin (Km and Vmax of 2.84 mg/mL protein, and 64.10 units/mg protein, respectively) than for citrus pectin. C. pubescens PME extract showed maximum activity at 0.4 moles/L NaCl, pH 7.5, and 55 °C. The Ea and Q10 for thermal activation were 36.27 kJ/mol and 2.01 (20-30 °C), respectively. About 50% of the activity still remained after heating for 25 min at 60 °C, and it was completely inactivated by incubation at 80 °C for 10 min. The Q10 and Ea values for thermal inactivation reaction were 20.06 (70-80 °C) and 146.16 kJ/mol, respectively. These results provide useful information about the factors that affect the activity of C. pubescens PME, and might be used as a starting point for texture control during post-harvest handling and processing of this fruit.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: LWT - Food Science and Technology - Volume 40, Issue 2, March 2007, Pages 278-284
Journal: LWT - Food Science and Technology - Volume 40, Issue 2, March 2007, Pages 278-284
نویسندگان
Maria A. Vivar-Vera, Juan A. Salazar-Montoya, Graciano Calva-Calva, Emma G. Ramos-RamÃrez,