Cannabis sativa L. is an annual species cultivated since antiquity for different purposes. While, in the past, hemp inflorescences were considered crop residues, at present, they are regarded as valuable raw materials with different applications, among which extraction of the essential oil (EO) has gained increasing interest in many fields. The aim of the present study is the evaluation of the yield and the chemical composition of the EO obtained by hydrodistillation from eleven hemp genotypes, cultivated in the same location for two consecutive growing seasons. The composition of the EOs was analyzed by GC–MS, and then subjected to multivariate statistical analysis. Sesquiterpenes represented the main class of compounds in all the EOs, both in their hydrocarbon and oxygenated forms, with relative abundances ranging from 47.1 to 78.5%; the only exception was the Felina 32 sample collected in 2019, in which cannabinoids predominated. Cannabinoids were the second most abundant class of compounds, of which cannabidiol was the main one, with relative abundances between 11.8 and 51.5%. The statistical distribution of the samples, performed on the complete chemical composition of the EOs, evidenced a partition based on the year of cultivation, rather than on the genotype, with the exception of Uso-31. Regarding the extraction yield, a significant variation was evidenced among both the genotypes and the years of cultivation.

Cannabis sativa L. has been long cultivated for its narcotic potential due to the accumulation of tetrahydrocannabinolic acid (THCA) in female inflorescences, but nowadays its production for fiber, seeds, edible oil and bioactive compounds has spread throughout the world. However, some hemp varieties still accumulate traces of residual THCA close to the 0.20% limit set by European Union, despite the functional gene encoding for THCA synthase (THCAS) is lacking. Even if some hypotheses have been produced, studies are often in disagreement especially on the role of the cannabichromenic acid synthase (CBCAS). In this work a set of European Cannabis genotypes, representative of all chemotypes, were investigated from a chemical and molecular point of view. Highly specific primer pairs were developed to allow an accurate distinction of different cannabinoid synthases genes. In addition to their use as markers to detect the presence of CBCAS at genomic level, they allowed the analysis of transcriptional profiles in hemp or marijuana plants. While the high level of transcription of THCAS and cannabidiolic acid synthase (CBDAS) clearly reflects the chemical phenotype of the plants, the low but stable transcriptional level of CBCAS in all genotypes suggests that these genes are active and might contribute to the final amount of cannabinoids.

Cannabis sativa has long been harvested for industrial applications related to its fibers. Industrial hemp cultivars, a botanical class of Cannabis sativa with a low expression of intoxicating Δ⁹-tetrahydrocannabinol (Δ⁹-THC) have been selected for these purposes and scarcely investigated in terms of their content in bioactive compounds. Following the global relaxation in the market of industrial hemp-derived products, research in industrial hemp for pharmaceutical and nutraceutical purposes has surged. In this context, metabolomics-based approaches have proven to fulfill the aim of obtaining comprehensive information on the phytocompound profile of cannabis samples, going beyond the targeted evaluation of the major phytocannabinoids. In the present paper, an HRMS-based metabolomics study was addressed to seven distinct industrial hemp cultivars grown in four experimental fields in Northern, Southern, and Insular Italy. Since the role of minor phytocannabinoids as well as other phytocompounds was found to be critical in discriminating cannabis chemovars and in determining its biological activities, a comprehensive characterization of phytocannabinoids, flavonoids, and phenolic acids was carried out by LC-HRMS and a dedicated data processing workflow following the guidelines of the metabolomics Quality Assurance and Quality Control Consortium. A total of 54 phytocannabinoids, 134 flavonoids, and 77 phenolic acids were annotated, and their role in distinguishing hemp samples based on the geographical field location and cultivar was evaluated by ANOVA-simultaneous component analysis. Finally, a low-level fused model demonstrated the key role of untargeted cannabinomics extended to lesser-studied phytocompound classes for the discrimination of hemp samples.

Hemp (Cannabis sativa L.) hurds, the inner bark of the stem, are a poorly appreciated part of the plant that typically represents waste. The aim of this experiment was to describe the physical characteristics, including moisture (M), water absorption (WA), and ammonia absorption (AA), of 10 hemp varieties (Fibranova, Codimono, USO31, CS, Futura 75, Eletta Campana, Carmaleonte, Felina 32, Santhica, and Ferimon) cultivated in Italy. Samples of hemp hurds were ground to 8 mm obtaining hemp shives. Values of M, WA, and AA were determined following the official procedures. The results showed an average of 7.78%, 251.9%, and 50.0% for M, WA, and AA, respectively. Data of M and WA were similar among varieties, whereas a significant difference was found for the AA, varying from 45.0 to 55.5% for the Fibranova and Ferimon varieties, respectively. In conclusion, hemp shives have good physical characteristics, similar to other commercial bedding materials (i.e., wood shavings) but other parameters and on-farm trials will be required to make a full assessment of hemp.

The study investigated the nutritional profile and nutraceutical composition of the seeds (whole and defatted) of two monoecious hemp cultivars (Carmaleonte, Codimono) and one dioecious cultivar (CS) grown during the 2018 and 2019 crop seasons. The phenolic acid profiles, both free and bound, antioxidant activity (AA), protein content (PC), total phenolic content (TPC), β-carotene, lutein content, and condensed tannins (CT) were studied, and the effects of genotype (G), year (Y), and GxY interaction were also measured. The results indicated the stronger involvement of the year in the nutritional and antioxidant properties of the whole seeds than in those of the defatted seeds, as indicated by the analysis of the variance. The PC, TPC, AA, sum of phenolics free (SPF), and sum of phenolics bound (SPB) were significantly affected by year, while the lutein and some phenolic acids, free and bound (ferulic and p-coumaric acids and N-trans-caffeoyltyramine), showed significant effects of the genotype. In this respect, the Carmaleonte revealed the highest content of ferulic and p-coumaric acids, as well as CS of N-trans-caffeoyltyramine. A prevalence of Y effect over G was measured in the free and bound fraction of the phenolics of the whole seeds, in contrast to the defatted seeds, in which significant effects of GxY were also measured. Moreover, the Pearson’s correlation coefficients indicated a strict involvement of precipitations in the variation of the phenolics accumulation, above all with bound p-hydroxybenzoic acid (r = 0.71 **), bound syringic acid (r = 0.69 *), bound N-trans-caffeoyltyramine (r = 0.64 *), and SPB (r = 0.60 *). As phenolics bound fractions have strong biological activities, (including antioxidant and anti-inflammatory activities) the high concentrations of N-trans-Caffeoyltyramine B in the CS defatted seeds suggest that it is valuable ingredient for functional foods.