Four undescribed pyrethrins from seeds of Pyrethrum cinerariifolium and their aphidicidal activity

Abstract

Four undescribed pyrethrins C-F (1–4) as well as four known pyrethrins (5–8) were isolated from seeds of Pyrethrumcinerariifolium Trev. The structures of compounds 1–4 were elucidated by UV, HRESIMS, and NMR (1H and 13C NMR, 1H-1H COSY, HSQC, HMBC and ROESY), among which the stereostructure of compound 4 was determined by calculated ECD. Furthermore, compounds 1–4 were evaluated for their aphidicidal activities. The insecticidal assay results showed that 1–4 exhibited moderate aphidicidal activities at the concentration of 0.1 mg/mL with the 24 h mortality rates ranging from 10.58 to 52.98%. Among them, pyrethrin D (2) showed the highest aphidicidal activity, with the 24 h mortality rate of 52.98%, which was slightly lower than the positive control (pyrethrin II, 83.52%). Graphical Abstract

Applicability of Food Monitoring Data for Assessing Relative Exposure Contributions of Pyrethroids in Retrospective Human Biomonitoring Risk Estimations

“…They are synthetic analogs of pyrethrins that mimic the insecticidal activity of Chrysanthemum cinerariaefolium flowers and cause distress in the central nervous system by changing the dynamics of sodium cation channels in neuronal membranes [ 1 ]. It is a group of high interest and under further development, e.g., new discoveries of natural pyrethrins [ 2 ] and new formulation approaches such as nanopestices [ 3 ]. Traditionally, pyrethroids have been divided into Type I and Type II pyrethroids, but mixed modes of action have been proposed in some cases [ 4 ].…”