کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10544162 | 963572 | 2005 | 13 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Partial purification and characterisation of polyphenol oxidase and peroxidase from marula fruit (Sclerocarya birrea subsp. Caffra)
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Partial purification and characterisation of polyphenol oxidase and peroxidase from marula fruit (Sclerocarya birrea subsp. Caffra) Partial purification and characterisation of polyphenol oxidase and peroxidase from marula fruit (Sclerocarya birrea subsp. Caffra)](/preview/png/10544162.png)
چکیده انگلیسی
Marula fruit, native to sub-Saharan Africa, is of growing commercially importance. Polyphenol oxidase (PPO) and peroxidase from the fruit were partially purified by a combination of temperature induced phase separation in Triton X-114, DEAE-ion exchange and Sephadex G100 gel filtration. PPO activity was purified 58-fold with 75% recovery while the purification factor for peroxidase was 19% with 25% recovery. The enzymes were characterised for enzyme concentration-reaction rate relationship, thermal stability, pH activity and stability, molecular weight, isoelectric point (pI) and kinetic parameters. PPO and peroxidase shared the same molecular weight (71 kDa) and pI (5.43). Thermal deactivation curves were bi-phasic for both activities. Peroxidase displayed maximal activity at pH 4.0 with ABTS (2,2â²-azino-(bis-3-ethylbenzthiazoline-6-sulfonic acid)) and a KM of 1.77 mM for hydrogen peroxide. The pH optimum for PPO was 7.0 with catechol. Marula PPO had KM values of 1.41, 1.43, 3.73 and 4.99 mM for catechin, 4-methylcatechol, 3,4-dihydroxyphenylpropanoic acid (DHPPA) and catechol, respectively.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Food Chemistry - Volume 92, Issue 2, September 2005, Pages 311-323
Journal: Food Chemistry - Volume 92, Issue 2, September 2005, Pages 311-323
نویسندگان
Kwanele M. Mdluli,