The extract is derived from the bulbs of red onions (Allium cepa). Its formula comprises a blend of bioactive compounds, including flavonoids, quercetin, and sulfur compounds. In cosmetics, Allium cepa bulb extract is prized for its soothing and antioxidant properties, which can help reduce skin inflammation and combat oxidative stress. It is often found in skincare products designed to promote skin health, calm irritation, and protect against environmental damage.