RT info:eu-repo/semantics/article T1 Insecticidal activity of spray dried microencapsulated essential oils of Rosmarinus officinalis and Zataria multiflora against Tribolium confusum A1 Ahsaei, Seyed Mohammad A1 Rodríguez Rojo, Soraya A1 Salgado, Marta A1 Cocero Alonso, María José A1 Jahromi, Khalil Talebi A1 Amoabediny, Ghassem AB Rosmarinus officinalis and Zataria multiflora (Lamiaceae) essential oils (EOs) contain components with insecticidal properties that can be used as pesticides for stored product pests. In the present study, they were encapsulated in octenyl succinic anhydride (OSA) - starch in order to test their insecticidal activity against Tribolium confusum. First an oil-in-water emulsion was prepared and afterwards, it was dried by spray-drying technique. The emulsions were characterized regarding particle size (461–854 nm), stability and encapsulated oil efficiency (68–88%). Also, solid formulations were characterized by particle size (8.29–11.35 μm), encapsulation efficiency (5–52%) and water activity (0.19–0.26). Further, the release rate at storage conditions (at 27 ± 3 °C and 70–75% relative humidity in the dark) was measured over a period of 40 days. The insecticidal activity against T. confusum was determined by specific bioassays performed at 27 ± 3 °C temperature and 70–75% relative humidity in the dark. Five concentrations were used for estimation of fumigant toxicity of rosemary and Zataria oils after 72 h exposure in adult beetles. Fumigant toxicity results revealed that microencapsulated oils were more effective than non-formulated oils against beetles in long time. Similarly, it was demonstrated that microencapsulation of the essential oils increases their persistence: non-formulated oils have not insecticidal activity after 15 days of the storage period, whereas at the same period, the mortality rate against T. confusum of rosemary and Zataria microencapsulated oils was 46.6 and 35.5%, respectively. PB Elsevier Ltd. YR 2020 FD 2020 LK https://uvadoc.uva.es/handle/10324/66055 UL https://uvadoc.uva.es/handle/10324/66055 LA eng NO Crop Protection 128 (2020) 104996 DS UVaDOC RD 17-jul-2024