Essential oils of Schisandra chinensis seeds and berries without seeds were separately extracted. A total of 55 compounds were identified in the essential oil of berries without seeds (EOB), representing 85.75% of the total content. A total of 52 compounds were identified in the essential oil of seeds (EOS), representing 89.74% of the total content. For EOB, the top three content compounds were α-cis-bergamotene (10.79%), 4,11-selinadiene (5.28%) and α-cadinol (5.19%), while the top three content compounds of EOS were ylangene (10.16%), β-himachalene (9.46%) and di-epi-α-cedrene (8.92%). The antioxidant activity of the essential oil was tested using the DPPH radical-scavenging method. The antioxidant activity of EOB was higher than EOS. The IC(50) values of EOB and EOS were 8.4 and 15.8 mg/mL, respectively. This study concluded that EOB and EOS were not only different in extraction yield but also in chemical composition and antioxidant activity.

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Rhipicephalus microplus is a major threat to the cattle industry worldwide. The intensive use of acaricides and repellents has resulted in drug resistance. Hence, effective and eco-friendly pest control alternatives are urgently needed, especially from natural plant resources. In this study, the acaricidal and repellent activities of nine herbs against the larvae and eggs of R. microplus were evaluated. The results showed that ethanol extracts of star anise (Illicium verum), chaulmoogra (Hydnocarpus anthelmintica), motherwart (Leonurus artemisia), mandarin orange peel (citri reticulatae pericarpium, i.e., peel of Citrus reticulata fruit), and stemona (Stemona sessilifolia) had good contact acaricidal activities of 100, 98, 94, 88 and 86%, respectively, whereas star anise and clove (Syzygium aromaticum) had good fumigant acaricidal activities of 98 and 96%, respectively. The hatching inhibition rate of star anise against R. microplus eggs was 100%. All nine herbs had good real-time repellent rates, but only castor bean and star anise had repellent effects after 48 h (81.3 and 79.6%, respectively). This is the first report of the acaricidal and repellent activities of these medicinal herbs against R. microplus. Ethanol extracts of these herbs might be considered as potential alternatives to chemical acaricides for control of R. microplus.