Isolation and identification of diterpenoids and lignans from the Juniperus sabina L. with insecticidal activities

Botanical insecticides have received extensive attention due to their environmental friendliness and biodegradability. The isolation and identification of active compounds are the most innovative and vigorous stages in botanical pesticide development. This study aims to isolate and identify the insecticidal compounds present in Juniperus sabina L., with the goal of establishing a scientific foundation for developing an environmentally friendly and cost-effective alternative to conventional synthetic pesticides.

Through bioassay-guided isolation, 13 active compounds were obtained, all of which demonstrated significant antifeedant activity against third instar larvae of Mythimna separata. Notably, the lignan compounds exhibited potent insecticidal properties and effectively inhibited larval growth and development. Among the compounds, 4'-demethylpodophyllotoxin (12) exhibited the most potent antifeedant activity against third instar larvae of M. separata, with a median antifeeding concentration (AFC₅₀) of 64.6 μg/mL. Meanwhile, yatein (6) demonstrated remarkable insecticidal activity against fourth instar larvae of Pieris rapae (half-maximal lethal concentration, LC₅₀ = 293 μg/mL) and third instar larvae of Plutella xylostella (LC₅₀ = 1.18 mg/mL). Additionally, yatein (6) displayed significant insect growth regulator effects on M. separata, including an increased abnormal pupation rate, prolonged pupal and larval durations, and a notable reduction in larval weight, pupation rate, emergence rate, egg hatchability, and single female oviposition number.

Our findings offer valuable insights into the discovery of novel insecticidal compounds derived from J. sabina. 4'-Demethylpodophyllotoxin (12) and yatein (6) exhibited significant potential as promising candidates for the development of new botanical pesticides. © 2025 Society of Chemical Industry.