Comparative study on chemical compositions and volatile profiles of seed oils from five common Cucurbitaceae species

The chemical compositions and volatile profiles of wax gourd seed oil (WGSO), watermelon seed oil (WSO), pumpkin seed oil (PSO), cucumber seed oil (CSO), and bitter gourd seed oil (BGSO) were comparatively explored for the first time. All oils complied with standards for physicochemical properties and BGSO had the highest phenolic content. Their mineral levels varied significantly. The fatty acid composition of WGSO, WSO, PSO, and CSO was similar, predominantly linoleic acid. Whereas BGSO exhibited a distinct fatty acid profile with 55.38 % α-eleostearic acid. All samples were rich in tocopherols and squalene, with WSO having the highest total tocopherol content and PSO having the highest squalene content. HS-GC-IMS and HS-SPME-GC-MS detected 118 and 67 VOCs, respectively, primarily consisting of aliphatic aldehydes, alcohols, esters, and ketones. Principal component analysis confirmed that BGSO had the most distinctive volatile characteristics, while the other four seed oils shared similar VOC profiles.