Seeking out new health products in the olive plant
Olive oil is delicious, and it’s also widely considered to be beneficial to our health. Various underlying ingredients explaining this are bioactive compounds: natural chemicals found within plants, which research suggests have antioxidant, anti-inflammatory and antimicrobial properties. In the EU-funded Olive-Net project, undertaken with the support of the Marie Skłodowska-Curie Actions programme, scientists searched for new bioactive compounds in the olive plant, O. europaea, while finding a use for environmental waste, too. “The olive processing industry is responsible for the production of a huge bulk of by-products that are harmful to the environment and have been a matter of study for many years,” explains Leandros Skaltsounis, professor of Pharmacognosy and Natural Product Chemistry at the National and Kapodistrian University of Athens and Olive-Net project coordinator. “However, both products and by-products of the olive processing industry contain considerable amounts of valuable substances,” he says. Olive-Net aimed to exploit these diverse raw materials to develop novel active ingredients for the pharmaceutical, nutraceutical and cosmetic industries. The team used state-of-the-art natural product chemistry and biology to find novel natural products from O. europaea and improve already existing ones. “The results have highlighted their potential and provide a solution to the disposal of by-products that cause serious environmental problems,” notes Skaltsounis.
Advanced analytical techniques
Samples of O. europaea, specifically olive oil, edible olives, olive mill wastewater, olive leaves and olive pomace, were collected from various places in Algeria, Greece and Morocco. The Olive-Net project used a range of innovative extraction techniques to find chemicals in the samples, including microwave-assisted extraction, which uses microwave energy to partition bioactive compounds from the sample matrix into the solvent, and adsorption resin chromatography, which separates molecules based on their properties. These extraction methods were paired with sophisticated analysis techniques, such as high-resolution liquid chromatography mass spectrometry known as HRLC-MS, which separates target compounds followed by their mass-based detection. The researchers also used nuclear magnetic resonance, a technique using magnetic fields to study the structure of chemicals. “The techniques studied the raw materials in a holistic way, each of them from a different perspective, to identify and highlight bioactive natural products,” adds Skaltsounis.
Novel extracts and new insights
Olive-Net produced a series of promising results from the diverse analytical sampling techniques. “The most important were the characterisation of emerging chemical entities from the Mediterranean olive products and by-products, and the broadening of knowledge on their beneficial health effects, specifically inflammation and ageing,” says Skaltsounis. The researchers found a wide range of biophenols – various types of bioactive compounds – in different materials coming from the olive tree. The team produced novel natural extracts and produced various new synthetic compounds. “The partners hope that through new funding they will be able to study in detail specific compounds and extracts that were produced, and most importantly study their biological evaluation,” Skaltsounis remarks.
A symbol of unity
The olive tree is key to European agriculture, and a shared cultural entity in countries across the Mediterranean. The project promoted shared knowledge exchange across partner countries. According to Skaltsounis: “It is very important that partners from different countries of the EU – Austria, France, Germany, Greece, Spain, Italy – and also Algeria, Morocco and Thailand were united as a consortium to study the endless possibilities of the olive tree.”
Olive-Net, olive, oil, products, waste, bioactive, compounds, extraction, analysis