A New Validated Method for Rapid Determination of OLEU Concentration in Dietary Supplements: Comparison with Total Phenol Content and Antioxidant Activity.

• Tác giả: Morgane Carrara, Krati Jian, Mary T Kelly, Delphine Margout-Jantac
• Ngôn ngữ: eng
• Ký hiệu phân loại: 070.4333 Journalism
• Thông tin xuất bản: England : Journal of dietary supplements , 2025
• Bộ sưu tập: NCBI
• ID: 641781

Tóm tắt

 The market for olive leaf dietary supplements is expanding rapidly and is valued at 37.15 million today. However, information on the control of these products is sketchy and the origin and variety of olives are rarely stated. The aim of this research was to validate a simple and rapid screening method for oleuropein determination in olive leaf dietary supplements. A matrix blank was prepared by removal of oleuropein from a mixture of dietary supplements and the matrix was then spiked with known concentrations to create a spiked matrix calibration curve in the range 5 - 40% oleuropein. Five replicate extractions and analyses of the matrix standards were carried out over 10 days. Precision was less than 6% RSD and linearity was demonstrated by the Fischer test. Extraction recovery was >
  90% and there was a strong linear relationship between authentic and matrix standards. All tested products conformed to the label claim which was strongly correlated with total polyphenols measured by the Folin-Ciocalteau method. Antioxidant activity was measured by the DPPH assay and was found to be strongly correlated with total phenol content and oleuropein concentration.