Investigation of bioactivities of , , and by gas chromatography-mass spectrometry.

species have attracted much attention for their potency in cancer treatment. However, investigating the bioactivities of species is a complex task, due to their diversity, slow growth, and endangered state. The most important species in China are (), (), and × (), which mainly grow in the northeastern region. This article probes deep into the differences among the leaves of , , and , with the aid of gas chromatography-mass spectrometry (GC-MS). Through GC-MS, 162 compounds were detected in the samples and found to contain 35 bioactive metabolites. On this basis, 20 metabolites with significant bioactivities (antibiotic, antioxidant, anticancer, and antiaging effects) were identified via unsupervised learning of principal component analysis and supervised learning of partial least squares-discriminant analysis. The results show that has the most prominent antibiotic, antioxidant, and anticancer effects, while has the most diverse and abundant metabolites that slow down aging.