Antioxidant and antibacterial activities of 13 ornamental herbaceous peony cultivars: a comparative study with stems and leaves

Paeonia lactiflora is an important ornamental and medicinal plant, but after the flowering period, the above-ground parts of ornamental cultivars are often discarded as waste. When considering the development of medicinal plant resources, attention should be paid to the comprehensive development and utilisation of the plant. In this study, 13 ornamental herbaceous peony cultivars were selected, and their stems and leaves were analysed for antioxidant and antibacterial activities. The results showed that total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity and antibacterial activity varied depending on the cultivar and plant organ. In the same cultivar, the TPC and TFC of leaves were higher than those of the stems. The antioxidant activity was significantly correlated with TPC of stems and leaves. In the antibacterial assay, the extracts of stem and leaves of the cultivars ‘Hong Yan Fei Shuang’ and ‘Chun Xiao’ were the most effective against most of the tested strains. This is an innovative study that shows the great potential of ornamental herbaceous peony stems and leaves as sources of biologically active compounds.