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Cannabis sativa L. is a plant known all over the world, due to its history, bioactivity and also social impact. It is chemically complex with an astonishing ability in the biosynthesis of many secondary metabolites belonging to different chemical classes. Among them, cannabinoids are the most investigated ones, given their pharmacological relevance. In order to monitor the composition of the plant material and ensure the efficacy and safety of its derived products, extraction and analysis of cannabinoids play a crucial role. In this context, in addition to a conventional separation method based on HPLC with UV/DAD detection, a new strategy based on a non-separation procedure, such as 13 C-qNMR, may offer several advantages, such as reduced solvent consumption and simultaneous acquisition of the quali/quantitative data related to many analytes. In the light of all the above, the aim of this work is to compare the efficiency of the above-mentioned analytical techniques for the study of the main cannabinoids in different samples of cannabis inflorescences, belonging to fibre-type, recreational and medical varieties. The 13 C-qNMR method here proposed for the first time for the quantification of both psychoactive and non-psychoactive cannabinoids in different cannabis varieties provided reliable results in comparison to the more common and consolidated HPLC technique., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Cannabis-based medications are being increasingly used for the treatment of different clinical conditions. Among all galenic formulations, olive oil extracts from medical Cannabis are the most prescribed ones for their easy preparation and usage. A great variety of methods have been described so far for the extraction of medical Cannabis oils to reach a high yield of Δ 9 -tetrahydrocannabinol (Δ 9 -THC), but poor attention has been paid to the preservation of the terpene fraction from the plant, which may contribute to the overall bioactivity of the extracts. In this context, the present study was aimed at the chemical characterization of different medical Cannabis oils prepared by following both innovative and existing extraction protocols, with particular attention to cannabinoids and terpenes, in order to set up a suitable method to obtain an extract rich in these chemical classes. In particular, six different extraction procedures were followed, based on different techniques, of which all but one included a decarboxylation of the plant material. The profile of cannabinoids was studied in detail by means of HPLC-ESI-MS/MS, while terpenes were characterized by means both GC-MS and GC-FID techniques coupled with solid-phase microextraction operated in the head-space mode (HS-SPME). An innovative method that is based on the extraction of the oil by dynamic maceration at room temperature from plant inflorescences, which were partially decarboxylated in a closed system at a moderate temperature and partially pre-extracted with ethanol, produced similar yields of bioactive compounds as that obtained by using a microwave-assisted distillation of the essential oil from the plant material, in combination with a maceration extraction of the oil from the residue. Both these new methods provided a higher efficiency over already existing extraction procedures of medical Cannabis oils and they can be applied to obtain a product with a high therapeutic value., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Aloysia polystachya (Griseb. et Moldenke) has not been deeply investigated in past years and currently data about its chemical composition are limited. Phenolic compounds characterization can be very difficult in vegetable matrices, owing to bonds to sugar moieties or conjugation, giving rise to complex structures. In this work, methanolic extracts of Aloysia polystachya leaves were analyzed by HPLC-ESI-MS, the favourite technique for the separation and quantification of their polyphenols. To assess the complete characterization and quantification of the phenylpropanoid fraction, three different MS techniques have been coupled to HPLC: ion trap mass spectrometry (Ion Trap LC/MS), quadrupole-time of flight high resolution mass spectrometry (Q-TOF HRMS) and triple-quadrupole (TQ LC/MS) for the quantification. Eleven phenylpropanoid glycosides were identified and quantified and, among them, the compounds forsythoside A, plantainoside C, purpureaside D, martynoside and its two isomers were detected for the first time to the best of our knowledge. The results presented here could be helpful to assess the quality of this plant and could further contribute to the chemotaxonomy of the genus., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Echinacea purpurea (L.) Moench, Echinacea angustifolia DC. var. angustifolia and Echinacea pallida (Nutt.) Nutt. are frequently used as medicinal plants and their preparations are among the most widely used herbal medicines. The extracts from these species have shown a highly complex chemical composition, including polar compounds (caffeic acid derivatives, CADs), non-polar compounds (alkylamides and acetylenic secondary metabolites; essential oil) and high molecular weight constituents (polysaccharides and glycoproteins). All these chemical classes of compounds have demonstrated to possess interesting biological activities. In the light of all the above, this paper is focused on the analytical techniques, including sample preparation tools and chromatographic procedures, for the chemical analysis of bioactive compounds in medicinally used Echinacea species. Since sample preparation is considered to be a crucial step in the development of analytical methods for the determination of constituents present in herbal preparations, the strength and weakness of different extraction techniques are discussed. As regards the analysis of compounds present in Echinacea plant material and derivatives, the application of different techniques, mainly HPLC, HPLC-ESI-MS, HPLC-ESI-MS/MS, HPCE, HPTLC and GC, is discussed in detail. The strength, weakness and applicability of the different separation tools are stated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A closed-vessel microwave-assisted extraction (MAE) technique was optimized for the first time for the extraction of polyphenols from raw propolis. The results obtained by means of response surface experimental design methodology showed that the best global response was reached when the extraction temperature was set at 106 °C, the solvent composition close to EtOH-H2O 80:20 (v/v), with an extraction time of 15 min. In comparison with other techniques, such as maceration, heat reflux extraction (HRE) and ultrasound-assisted extraction (UAE), the extraction with MAE was improved by shorter extraction time and lower volume of solvent needed. The HPLC analyses of propolis extracts were carried out on a fused-core Ascentis Express C18 column (150 mm × 3.0 mm I.D., 2.7 μm), with a gradient mobile phase composed by 0.1% formic acid in water and acetonitrile. Detection was performed by DAD and MS. The method validation indicated that the correlation coefficients were >0.999; the limit of detection was in the range 0.5-0.8 μg/ml for phenolic acids and 1.2-3.0 μg/ml for flavonoids; the recovery range was 95.3-98.1% for phenolic acids and 94.1-101.3% for flavonoids; the intra- and inter-day %RSD values for retention times and peak areas were ≤ 0.3 and 2.2%, respectively. The quali- and quantitative analysis of polyphenols in Italian samples of raw propolis was performed with the validated method. Total phenolic acids ranged from 5.0 to 120.8 mg/g and total flavonoids from 2.5 to 168.0mg/g. The proposed MAE procedure and HPLC method can be considered reliable and useful tools for the comprehensive multi-component analysis of polyphenols in propolis extracts to be used in apitherapy., (Copyright © 2013 Elsevier B.V. All rights reserved.)