Oil-loaded gels fight fungus

Thanks to their ability to evaporate at ordinary temperatures, essential oils are popular components in perfume. But this volatility makes it difficult to take advantage of essential oils’ pharmacological properties: they can vanish into the air before they’ve had a chance to work their magic. Technion chemists Boaz Mizrahi and Sivan Yogev discovered that they could release essential oils in a controlled fashion by capturing them in organogels (ACS Appl. Polym. Mater. 2020, DOI: 10.1021/acsapm.0c00269). Organogels are soft materials made of a polymeric matrix, like ethyl cellulose, and an organic solvent, such as vegetable oil. Mizrahi and Yogev made organogels using citral, a component of lemongrass; linalool, which is found in lavender and mint essential oils; and an essential oil of Mentha arvensis, also known as wild mint. They found that citral organogels and organogels with high concentrations of linalool and M. arvensis were able to kill the pathogenic fungus Trichophyton rubrum, the most common cause of athlete’s foot. They also found the organogels were able to successfully fight fungal infection in horse hooves in lab experiments. In addition, containers with essential oil–loaded organogels were able to keep cherry tomatoes fresher longer than containers with canola oil–loaded gels or with no organogels (shown). Although the idea of using essential oils in food containers isn’t new, Mizrahi says this system can go into existing packaging.