Acaricidal activity of components of Cryptomeria japonica against spider mites

Variations in Essential Oil Chemical Composition and Biological Activities of Cryptomeria japonica (Thunb. ex L.f.) D. Don from Different Geographical Origins—A Critical Review

“…The results revealed that C. japonica leaf EO is often characterized by two or more major compounds, which may be present in similar amounts, and that in most countries, namely in East Asia, ent-kaurene is the major C. japonica leaf EO constituent, followed by elemol. However, based on other geographical regions and using PCA (Figure 2), we can categorized the C. japonica leaf EO into three distinct chemotypes, regarding major constituents: (1) ent-kaurene chemotype (very frequent in Taiwan [10] and Korea [30]) (2) elemol plus ent-kaurene chemotype (more frequent in Japan [31], China [27] and Nepal [11]) and (3) α-pinene chemotype (found in Azores islands [32], Corsica island [33] and Japan [18]). The corresponding PCs data are found in Table 2.…”

“…It is believed that these diterpenes chemotypes are mainly genetically controlled [27,33,42]. Moreover, Yamashita et al [31] had reported that the diterpene chemotype of the leaves has an impact on the biological activity of the EO, i.e., the ent-kaurene chemotype exhibited higher acaricidal activity than the other diterpene hydrocarbon chemotypes (phyllocladene or ent-sclarene), where the difference between ent-kaurene and phyllocladene was a diastereomer with the same planar structure. This study [31] highlights the importance of the stereostructure/stereochemistry of the compounds on their biological activities.…”

Effect of the extract and compound from Solanum nigrum Linn on Tetranychus cinnabarinus

“…Moreover, similar results were observed by Pavela (2016), who published the efficacy of aqueous extracts obtained from 28 plant species, and extracts obtained from Saponaria officinalis roots and Ammi visnaga seeds were found to provide the significantly highest efficacies with LC 50 of 10.3 and 12.5 g/l, respectively, which are still much higher than S. nigrum crude extract, even though they were tested against Tetranychus urticae Koch, whereas the methanol extract of A. visnaga seeds showed a more remarkable persistence than the extract we tested in this study, for which LC 90 was estimated as lower than 5.0 g/l against adult T. urticae after 10 days of treatment (Pavela 2015). Furthermore, many other plant extracts from different families found by various authors are considered acaricides under in vitro laboratory conditions, including Eucalyptus camaldulensis (Mansour et al 2004), K. scoparia (Shi et al 2006), Aloe vera L. (Wei et al 2011), Phytolacca americana L. , Rosmarinus officinalis and Salvia officinalis (Laborda et al 2013), Callistemon viminalis, Eucalyptus bicostata, Eucalyptus maidenii, Eucalyptus sideroxylm and Eucalyptus approximans (Roh et al 2013), Cryptomeria japonica (Yamashita et al 2015) and Chenopodium quinoa Willd. (Harder et al 2016).…”

Growth-inhibitory activity of components in Cryptomeria japonica leaves against Robinia pseudoacacia

“…The TLC analysis in the separation of ethyl acetate extract was performed using a mixed solvent of hexane: ethyl acetate (1:1) or ethyl acetate:methanol (4:1, 3:2, and 1:1). Components were identified by comparison of their GC-MS spectra with those of standard samples isolated during our previous studies (Yamashita et al 2015;Suzuki et al 2018) and/or samples supplied from Dr Nagahama (Sojo University). β-Eudesmol was isolated by further column chromatography from the sesquiterpene alcohol fraction of the hexane extract.…”

“…However, its leaves have not been utilized effectively and many of the materials generated by the timber industry are regarded as forest wastes rather than potentially useful resources. Some components of Sugi have allelopathic activities against fungi (Chen et al 2005) and arthropods (Chen et al 2012;Yamashita et al 2015). Especially, growth-inhibitory activities against plants have been found in terpenoid and flavonoid compounds contained in Sugi (Sekine et al 2012;Suzuki et al 2018).…”