𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Purification and characterisation of carrot (Daucus carota L) pectinesterase

✍ Scribed by Jesús Alonso; Wenceslao Canet; Nazlin Howell; Rafael Alique

Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
156 KB
Volume
83
Category
Article
ISSN
0022-5142

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

A pectinesterase isoform with an alkaline isoelectric point of over 8.66 was detected in crude extracts of carrot. The enzyme was purified by ion exchange and molecular exclusion chromatography. The molecular weight of the isoform was 25 kDa, determined in native conditions by filtration through Sephadex G‐75 SF. The enzyme showed a high affinity for its substrate, with K~m~ and V~max~ values of 0.031 mg ml^−1^ and 6.77 units respectively for apple pectin. The pectinesterase activity exhibited an optimum around pH 7.4 and was activated by metallic ions, with optimum activities at NaCl concentrations between 130 and 330 mM and at CaCl~2~ concentrations between 15 and 50 mM. The enzyme was activated most by Ca^2+^ and exhibited a greater tolerance of high concentrations of Na^+^. Comparison of its heat stability with other pectinesterases of vegetable origin indicated that the purified isoform was very thermolabile, being rendered inactive by heating for 5 min at 70 °C. The enzyme was inhibited by high concentrations of polygalacturonic acid and competitively inhibited by D‐galacturonic acid, with a K~i~ value of 1 mM. Copyright © 2003 Society of Chemical Industry

📜 SIMILAR VOLUMES

Nitrogen nutrition and flavour compounds
Nitrogen nutrition and flavour compounds of carrots (Daucus carota L) cultivated in Mitscherlich pots
✍ Schaller, Robert G; Schnitzler, Wilfried H 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 126 KB

Carrots (Daucus carota L) of the cultivar `Nanthya' F 1 were grown in Mitscherlich pots containing quartz sand with inorganic nitrogen fertilisation (®ve levels, four replications) and timecontrolled drip irrigation. The effect of different nitrogen uptake on the yield and on the amount and composit

Protective effect of carrot (Daucus caro
Protective effect of carrot (Daucus carota L.) against lindane - induced hepatotoxicity in rats
✍ P. Balasubramaniam; L. Pari; Venugopal P. Menon 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 82 KB 👁 2 views

Daucus carota commonly known as carrot, is widely used in European folk medicine for the treatment of jaundice and hepatic disorders. Oral administration of carrot extract (25 mL/kg/day) for 30 days produced significant hepatoprotection against lindane (20 mg/kg/day) induced hepatotoxicity in rats.

Supercritical fluid carbon dioxide extra
Supercritical fluid carbon dioxide extraction of α-and β-carotene from carrot (Daucus carota L.)
✍ Amitabh Chandra; Muraleedharan G. Nair 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 106 KB 👁 1 views

Carrots (Daucus carota L. var. Caro Pride) were extracted with supercritical fluid carbon dioxide (SFOC 2 ) under various combinations of pressures and solvent modifiers at 40°C and analysed for their ␣and ␤-carotene content by high pressure liquid chromatography. The SFCO 2 extraction at 40°C and 6

Activity, localisation and thermal inact
Activity, localisation and thermal inactivation of deteriorative enzymes in Australian carrot (Daucus carota L) varieties
✍ Vora, Harshul M; Kyle, William S?A; Small, Darryl M 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 115 KB

Four Australian carrot varieties have been selected for a study of deteriorative enzymes. The varieties included those commonly used for table and also for processing purposes (Red Hot Original, Red Count, Top Pak and Red Hot Carotene 100). The activities of three deteriorative enzymes (peroxidase,