Abstract
Background
Olive leaf extract, and key constituents including oleuropein and hydroxytyrosol, are generating clinical and research interest as cardiovascular risk modifiers. Positive effects have been reported on blood pressure, inflammation, immune function, and insulin resistance, and olive leaf extracts are widely sold in pharmacy and dispensed by naturopaths and herbalists.
Objective
To evaluate the phytochemical profiles of different olive leaf extracts, and compare over-the-counter olive leaf products and olive leaf products for practitioner-based extemporaneous dispensing.
Method
A total of ten olive leaf liquid products were quantified for oleuropein, hydroxytyrosol and total biophenols in an Australian specialist olive chemistry laboratory, using reversed phase high performance liquid chromatography. Five products were Australian over-the-counter liquid extracts, and five were Australian practitioner-only liquid extracts.
Results
Considerable variation in oleuropein, hydroxytyrosol and total biophenol levels was observed between individual products. Of additional interest was a significant variation in oleuropein and hydroxytyrosol levels and ratios between over-the-counter and practitioner products.
Discussion
This research demonstrates substantial variability between olive leaf extracts available to pharmacists, naturopaths and herbalists. Such variability raises the question for pharmacists and other health professionals as to whether clinical results from different olive leaf extracts will be consistent, comparable, or reliable.
Olive leaf extract, and key constituents including oleuropein and hydroxytyrosol, are generating clinical and research interest as cardiovascular risk modifiers. Positive effects have been reported on blood pressure, inflammation, immune function, and insulin resistance, and olive leaf extracts are widely sold in pharmacy and dispensed by naturopaths and herbalists.
Objective
To evaluate the phytochemical profiles of different olive leaf extracts, and compare over-the-counter olive leaf products and olive leaf products for practitioner-based extemporaneous dispensing.
Method
A total of ten olive leaf liquid products were quantified for oleuropein, hydroxytyrosol and total biophenols in an Australian specialist olive chemistry laboratory, using reversed phase high performance liquid chromatography. Five products were Australian over-the-counter liquid extracts, and five were Australian practitioner-only liquid extracts.
Results
Considerable variation in oleuropein, hydroxytyrosol and total biophenol levels was observed between individual products. Of additional interest was a significant variation in oleuropein and hydroxytyrosol levels and ratios between over-the-counter and practitioner products.
Discussion
This research demonstrates substantial variability between olive leaf extracts available to pharmacists, naturopaths and herbalists. Such variability raises the question for pharmacists and other health professionals as to whether clinical results from different olive leaf extracts will be consistent, comparable, or reliable.
| Original language | English |
|---|---|
| Publication status | Published - 2019 |
| Event | Pharmaceutical Society of Australia Conference - Sydney, Australia Duration: 26 Jul 2019 → 28 Jul 2019 |
Conference
| Conference | Pharmaceutical Society of Australia Conference |
|---|---|
| Country/Territory | Australia |
| City | Sydney |
| Period | 26/07/19 → 28/07/19 |