The essential oil of Kochia scoparia (L.) Schrad. as a potential repellent against stored-product insects.

Chemical composition of the essential oil from Kochia scoparia (L.) Schrad. (syn. Bassia scoparia (L.) A. J. Scott) was analyzed in quality and quantity by GC-MS and GC-FID. Repellent activities of the essential oil from K. scoparia (KSEO) were evaluated against two common species of stored-product insects Tribolium castaneum Herbst and Liposcelis bostrychophila Badonnel. Results indicated that KSEO mainly consisted of eugenol, ß-caryophyllene, and α-humulene, accounting for 75.6%, 8.2%, and 1.4% of the total oil, respectively. KSEO and the three major components were repellent to T. castaneum and L. bostrychophila adults. Notably, KSEO exerted significant effects, comparable to the positive control DEET at 2 and 4 h post-exposure. Eugenol at 63.17-2.53 nL/cm2 exhibited high percentage repellency ranging from 96 to 70% against L. bostrychophila during 4-h exposure. To gain further insights into the repellent activity, molecular docking simulation was performed with eugenol as the ligand and an odorant binding protein TcOBPC12 (gene: TcOBP10B) from the model insect T. castaneum as the receptor. Docking calculation results revealed that TcOBPC12 had binding affinity to eugenol (△G = - 4.52 kcal/mol) along with a hydrogen bond of 0.18 nm (1.8 Å) long forming between them, which could be an important target protein associated with identifying volatile repellent molecules. This work highlights the promising potential of KSEO as a botanical repellent for controlling stored-product insects.

[Effects and evaluation of different processing and drying methods on components in Paeoniae Radix Alba].

The present study evaluates different processing and drying methods and investigates their effects on the chemical components in Paeoniae Radix Alba via content determination. The fresh medicinal materials of Paeoniae Radix Alba collected from Bozhou of Anhui province were processed(boiled and peeled) and dried(hot air-dried, infrared-dried, and microwave-dried) at different temperatures(40, 50, 60 and 70 ℃), and the 11 components(monoterpene glycosides, polyphenols, tannin, and benzoic acid) in Paeoniae Radix Alba were determined by ultra-performance liquid chromatography coupled to triple quadrupole with electrospray tandem mass spectrometry(UPLC-TQ-MS). Then the compounds in processed and dried samples were analyzed by partial least squares discriminant analysis(PLS-DA) and orthogonal partial least squares discriminant analysis(OPLS-DA), and the contribution rates of differential components were evaluated by variable important in projection(VIP). The results indicated that the samples obtained by different processing and drying methods could be distinguished. Albiflorin, gallic acid, 1,2,3,4,6-pentakis-O-galloyl-ß-D-glucose, and benzoic acid were the common differential components in boiled Paeoniae Radix Alba. Benzoic acid was the common differential component in peeled Paeoniae Radix Alba. Gallic acid was the common differential component in Paeoniae Radix Alba dried by different methods. The samples could not be distinguished after drying at different temperatures due to the lack of common differential components. This study is expected to provide a reference for the selection of processing and drying methods and the optimization of processing parameters.

[Comparative study on differences of Paeonia lactiflora from different habitats based on fingerprint and chemometrics].

This study aims to compare the differences of Paeonia lactiflora from different habitats by establishing fingerprint. The fingerprint of P. lactiflora was established by UPLC. The samples collected from Sichuan,Hebei,Henan,Shanxi and Anhui were analyzed. The common peaks were identified by UPLC-Q-TOF/MS. The relative peak area of the common peaks was analyzed through similarity evaluation system( 2012 edition) for chromatographic fingerprint of traditional Chinese medicine developed by the National Pharmacopoeia Commission. Twelve common peaks were obtained and ten components were identified by reference substance and literature comparison. The similarity of each sample to the reference fingerprint is greater than 0. 900. However,all samples were clearly divided into 5 groups according to habitats after PLS-DA analysis. The peaks 2,6( ethyl gallate),10( galloypaeoniflorin) and 12( benzoyl paeoniflorin) were found to be the main difference components between the samples from five different habitats through the VIP value map. The study found that the variety of ingredients in the different areas are basically similar. But there are some differences in the content of the four components. The results of this study can provide reference at choosing and utilizing P. lactiflora from different places comprehensively.