• Home
  • Search Results
  • Endogenous enzymes involved in the transformation of oleuropein in Spanish table olive varieties.

Endogenous enzymes involved in the transformation of oleuropein in Spanish table olive varieties.

Journal of agricultural and food chemistry (2014-09-12)
Eva Ramírez, Eduardo Medina, Manuel Brenes, Concepción Romero
ABSTRACT

The main Spanish table olive varieties supplied by different olive cooperatives were investigated for their polyphenol compositions and the endogenous enzymes involved in their transformations during two growing seasons. Olives of the Manzanilla variety had the highest concentration in total polyphenols, followed by the Hojiblanca and Gordal varieties. The Gordal and Manzanilla cultivars showed the highest polyphenol oxidase activities. The Gordal cultivar presented a greater β-glucosidase and esterase activity than the others. An important influence of pH and temperature on the optimal activity of these enzymes was also observed. The polyphenol oxidase activity increased with temperature, and peroxidase activity was optimal at 35 °C. The β-glucosidase and esterase activities were at their maximum at 30 and 55 °C, respectively. The oxidase and β-glucosidase activities were at their maximum at the pH of the raw fruit. These results will contribute to the knowledge of the enzyme transformation of oleuropein in natural table olives.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Caffeic acid, ≥98.0% (HPLC)
Sigma-Aldrich
4-Nitrophenol, ReagentPlus®, ≥99%
Sigma-Aldrich
p-Coumaric acid, ≥98.0% (HPLC)
Sigma-Aldrich
Apigenin, ≥95.0% (HPLC)
Sigma-Aldrich
4-Nitrophenyl acetate, esterase substrate
Sigma-Aldrich
Guaiacol, natural, ≥99%, FG
Sigma-Aldrich
Guaiacol, oxidation indicator
Sigma-Aldrich
Luteolin, ≥98% (TLC), powder
Sigma-Aldrich
4-Nitrophenol, spectrophotometric grade
Supelco
Guaiacol, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
4-Nitrophenol, PESTANAL®, analytical standard
Sigma-Aldrich
4-Nitrophenol solution, 10 mM
Supelco
Luteolin, analytical standard
Sigma-Aldrich
2-(4-Hydroxyphenyl)ethanol, 98%
Supelco
Apigenin, analytical standard
Supelco
Luteolin 7-glucoside, analytical standard
Supelco
trans-p-Coumaric acid, analytical standard
Supelco
2-(4-Hydroxyphenyl)ethanol, analytical standard
Sigma-Aldrich
Luteolin 7-O-β-D-glucoside, ≥98.0% (HPLC)
Supelco
Acetaminophen Related Compound F, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Caffeic acid, matrix substance for MALDI-MS, ≥99.0% (HPLC)
Supelco
4-Nitrophenol
Luteolin, primary reference standard
Apigenin, primary reference standard
Supelco
4-Nitrophenol solution, certified reference material, 5000 μg/mL in methanol
Luteolin 7-glucoside, primary reference standard
Guaiacol, European Pharmacopoeia (EP) Reference Standard