Cannabis cultivation: Methodological issues for obtaining medical-grade product

In the weeds: A comprehensive review of cannabis; its chemical complexity, biosynthesis, and healing abilities

For millennia, various cultures have utilized cannabis for food, textile fiber, ethno-medicines, and pharmacotherapy, owing to its medicinal potential and psychotropic effects. An in-depth exploration of its historical, chemical, and therapeutic dimensions provides context for its contemporary understanding. The criminalization of cannabis in many countries was influenced by the presence of psychoactive cannabinoids; however, scientific advances and growing public awareness have renewed interest in cannabis-related products, especially for medical use. Described as a 'treasure trove,' cannabis produces a diverse array of cannabinoids and non-cannabinoid compounds. Recent research focuses on cannabinoids for treating conditions such as anxiety, depression, chronic pain, Alzheimer's, Parkinson's, and epilepsy. Additionally, secondary metabolites like phenolic compounds, terpenes, and terpenoids are increasingly recognized for their therapeutic effects and their synergistic role with cannabinoids. These compounds show potential in treating neuro and non-neuro disorders, and studies suggest their promise as antitumoral agents. This comprehensive review integrates historical, chemical, and therapeutic perspectives on cannabis, highlighting contemporary research and its vast potential in medicine.

Advancement of Research Progress on Synthesis Mechanism of Cannabidiol (CBD)

Cannabis sativa L. is a multipurpose crop with high value for food, textiles, and other industries. Its secondary metabolites, including cannabidiol (CBD), have potential for broad application in medicine. With the CBD market expanding, traditional production may not be sufficient. Here we review the potential for the production of CBD using biotechnology. We describe the chemical and biological synthesis of cannabinoids, the associated enzymes, and the application of metabolic engineering, synthetic biology, and heterologous expression to increasing production of CBD.

Effects of cannabidiol, with and without ∆9-tetrahydrocannabinol, on anxiety-like behavior following alcohol withdrawal in mice

Introduction

Alcohol use disorder (AUD) is commonly associated with anxiety disorders and enhanced stress-sensitivity; symptoms that can worsen during withdrawal to perpetuate continued alcohol use. Alcohol increases neuroimmune activity in the brain. Our recent evidence indicates that alcohol directly modulates neuroimmune function in the central amygdala (CeA), a key brain region regulating anxiety and alcohol intake, to alter neurotransmitter signaling. We hypothesized that cannabinoids, such as cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC), which are thought to reduce neuroinflammation and anxiety, may have potential utility to alleviate alcohol withdrawal-induced stress-sensitivity and anxiety-like behaviors via modulation of CeA neuroimmune function.

Methods

We tested the effects of CBD and CBD:THC (3:1 ratio) on anxiety-like behaviors and neuroimmune function in the CeA of mice undergoing acute (4-h) and short-term (24-h) withdrawal from chronic intermittent alcohol vapor exposure (CIE). We further examined the impact of CBD and CBD:THC on alcohol withdrawal behaviors in the presence of an additional stressor.

Results

We found that CBD and 3:1 CBD:THC increased anxiety-like behaviors at 4-h withdrawal. At 24-h withdrawal, CBD alone reduced anxiety-like behaviors while CBD:THC had mixed effects, showing increased center time indicating reduced anxiety-like behaviors, but increased immobility time that may indicate increased anxiety-like behaviors. These mixed effects may be due to altered metabolism of CBD and THC during alcohol withdrawal. Immunohistochemical analysis showed decreased S100β and Iba1 cell counts in the CeA at 4-h withdrawal, but not at 24-h withdrawal, with CBD and CBD:THC reversing alcohol withdrawal effects..

Discussion

These results suggest that the use of cannabinoids during alcohol withdrawal may lead to exacerbated anxiety depending on timing of use, which may be related to neuroimmune cell function in the CeA.

Cannabis sativa L. from Seized Drug Material: In Vitro Germination and Establishment

Background: With the expansion of the cannabis-derived product market, there is a growing need for seedling development to produce raw material for pharmaceutical applications and medicinal research. However, cannabis cultivation is illegal in many countries, and legal producers do not sell cannabis seeds in these countries. In Brazil, cannabis is still illegal, and the only way to obtain access to cannabis plants for research or as medicine is through importation, which is costly and requires authorization from the National Health Surveillance Agency (ANVISA), or from material seized by the police from drug trafficking. Methods: Therefore, since cannabis seeds obtained from drug trafficking have never been tested regarding their viability and use in in vitro cultivation, the aim of this study was to analyze the in vitro establishment of cannabis from seeds derived from Brazilian drug trafficking seizures that were provided by the police to investigate seed disinfestation procedures and further multiplication of nodal segments, with the purpose of obtaining material for medicinal research in the country. Seeds were subjected to four disinfestation treatments. Results: The best disinfestation treatment consisted in submerging the seeds in a 2 g·L-1 Captan® solution for 30 min before following the standard procedure with 70% ethanol for 30 sec and then 20 min in 2.5% sodium hypochlorite. The in vitro establishment of cannabis from seeds originating from Brazilian drug trafficking seizures was successful. The germination rate ranged from 10% to 90% according to the sample material. Non-brick weed, which consisted of dry leaves, stalks, and flowers, was more suitable for seed extraction and germination. Clones originating from BW4b showed the best development results compared with others. Conclusions: This is the first report of in vitro cannabis use in Brazil and opens great prospects for future work on its cultivation and research for medicinal applications in the country without relying on seed importation.

Optimizing medicinal hemp production with synergistic light-enhanced technologies and organic biorefinery approaches

This study explores the application of sustainable organic and biorefinery methods to increase the production of therapeutic hemp. Specifically, it focuses on Solodiol, Carmagnola, and Doctor Seedman strains. The study was carried out for 60 days in a highly controlled setting. It employed a unique combination of Murashige and Skoog (MS) media, supplemented with 2,4-D (0.5 mg/L) and kinetin (0.5 mg/L), and augmented with organic additions such as coconut water. This distinctive amalgamation facilitated extraordinary expansion across all varieties. The Solodiol strain demonstrated remarkable growth characteristics in terms of the number of branches, leaves, shoots, and height, whilst Carmagnola and Doctor Seedman indicated significant differences in diameter. Carmagnola, specifically, flourished in specific conditions: a strict 16-h period of light followed by 8 h of darkness, particularly when exposed to blue light. The Carmagnola strain, grown using MS feed (2StemMS), produced a hemp oil extract with a high concentration of 3.85%, compared to the Solodiol and Doctor Seedman strains, and also showcases their potential in promoting an environmentally friendly and therapeutically helpful medicinal hemp industry.

Non-destructive assessment of cannabis quality during drying process using hyperspectral imaging and machine learning

Cannabis sativa L. is an industrially valuable plant known for its cannabinoids, such as cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), renowned for its therapeutic and psychoactive properties. Despite its significance, the cannabis industry has encountered difficulties in guaranteeing consistent product quality throughout the drying process. Hyperspectral imaging (HSI), combined with advanced machine learning technology, has been used to predict phytochemicals that presents a promising solution for maintaining cannabis quality control. We examined the dynamic changes in cannabinoid compositions under diverse drying conditions and developed a non-destructive method to appraise the quality of cannabis flowers using HSI and machine learning. Even when the relative weight and water content remained constant throughout the drying process, drying conditions significantly influenced the levels of CBD, THC, and their precursors. These results emphasize the importance of determining the exact drying endpoint. To develop HSI-based models for predicting cannabis quality indicators, including dryness, precursor conversion of CBD and THC, and CBD : THC ratio, we employed various spectral preprocessing methods and machine learning algorithms, including logistic regression (LR), support vector machine (SVM), k-nearest neighbor (KNN), random forest (RF), and Gaussian naïve Bayes (GNB). The LR model demonstrated the highest accuracy at 94.7-99.7% when used in conjunction with spectral pre-processing techniques such as multiplicative scatter correction (MSC) or Savitzky-Golay filter. We propose that the HSI-based model holds the potential to serve as a valuable tool for monitoring cannabinoid composition and determining optimal drying endpoint. This tool offers the means to achieve uniform cannabis quality and optimize the drying process in the industry.

In silico genome-wide analysis of homeodomain-leucine zipper transcription factors in Cannabis sativa L

HD-Zip (Homeodomain-Leucine Zipper) is a family of transcription factors unique to higher plants and plays a vital role in plant growth and development. Increasing research results show that HD-Zip transcription factors are widely involved in many life processes in plants. However, the HD-Zip transcription factor for cannabis, a valuable crop, has not yet been identified. The sequence characteristics, chromosome localization, system evolution, conservative motif, gene structure, and gene expression of the HD-Zip transcription factor in the cannabis genome were systematically studied. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to verify its function. The results showed that cannabis contained 33 HD-Zip gene members. The number of amino acids is 136-849aa, the isoelectric point is 4.54-9.04, and the molecular weight is 23264.32-93147.87Da. Many cis-acting elements are corresponding to hormone and abiotic stress in the HD-Zip family promoter area of cannabis. Sequencing of the transcriptome at 5 tissue sites of hemp, stems, leaves, bracts, and seeds showed similar levels of expression of 33 members of the HD-Zip gene family at 5 tissue sites. Bioinformatics results show that HD-Zip expression is tissue-specific and may be influenced by hormones and environmental factors. This lays a foundation for further research on the gene function of HD-Zip.

Effect of augmented nutrient composition and fertigation system on biomass yield and cannabinoid content of medicinal cannabis (Cannabis sativa L.) cultivation

Growing evidence underscores the role of nutrients and fertigation systems in soilless production, influencing medicinal cannabis biomass and secondary metabolite content. This study delves into the impact of enhanced nutrient regimes on the 'ionome' and its ramifications for biomass and cannabinoid production in medicinal cannabis, comparing two distinct fertigation systems: recirculation and drain-to-waste. Notably, we assess the optimal harvest time for maximizing profitability. In comparing the experimental variant with elevated levels of phosphorus (P), potassium (K), and iron (Fe) in the nutrient solution to the control variant, we observe distinct patterns in element composition across stems, leaves, and flowers, with significant differences between fertigation systems. Total nitrogen content was determined through the Kjeldahl method. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were employed for elemental analysis. Cannabinoid identification and quantification used high-performance liquid chromatography with a diode-array detector (HPLC/DAD). Followed statistical analyses included ANOVA and Tukey's HSD test. Although the augmented nutrient regimen does not substantially increase plant biomass, interesting differences emerge between the two fertigation systems. The recirculation fertigation system proves more profitable during the recommended harvest period. Nonetheless, the altered nutrient regime does not yield statistically significant differences in final inflorescence harvest mass or cannabinoid concentrations in medicinal cannabis. The choice of fertigation system influences the quantity and quality of harvested inflorescence. To optimize the balance between the dry biomass yield of flowers and cannabinoid concentration, primarily total THC yield (sum of tetrahydrocannabinolic acid, Δ9-tetrahydrocannabinol, and Δ8-tetrahydrocannabinol), we propose the 11th week of cultivation as the suitable harvest time for the recirculation system. Importantly, the recirculation system consistently outperformed the drain-to-waste system, especially after the ninth week, resulting in significantly higher total THC yields. Enriched nutrition, when compared with control, increased THC yield up to 50.7%, with a remarkable 182% surge in the recirculation system when compared with the drain-to-waste system.

Effects of cannabis smoking on the respiratory system: A state-of-the-art review

The diminished perception of the health risks associated with the consumption of cannabis (marijuana) lead to a progressive increase in its inhalational use in many countries. Cannabis can be smoked through the use of joints, spliffs and blunts, and it can be vaporised with the use of hookah or e-cigarettes. Delta-9 tetrahydrocannabinol (THC) is the main psychoactive component of cannabis smoke but contains numerous other substances. While the recreational use of cannabis smoking has been legalised in several countries, its health consequences have been underestimated and undervalued. The purpose of this review is to critically review the impact of cannabis smoke on the respiratory system. Cannabis smoke irritates the bronchial tree and is strongly associated with symptoms of chronic bronchitis, with histological signs of airway inflammation and remodelling. Altered fungicidal and antibacterial activity of alveolar macrophages, with greater susceptibility to respiratory infections, is also reported. The association with invasive pulmonary aspergillosis in immunocompromised subjects is particularly concerning. Although cannabis has been shown to produce a rapid bronchodilator effect, its chronic use is associated with poor control of asthma by numerous studies. Cannabis smoking also represents a risk factor for the development of bullous lung disease, spontaneous pneumothorax and hypersensitivity pneumonitis. On the other hand, no association with the development of chronic obstructive pulmonary disease was found. Finally, a growing number of studies report an independent association of cannabis smoking with the development of lung cancer. In conclusion, unequivocal evidence established that cannabis smoking is harmful to the respiratory system. Cannabis smoking has a wide range of negative effects on respiratory symptoms in both healthy subjects and patients with chronic lung disease. Given that the most common and cheapest way of assumption of cannabis is by smoking, healthcare providers should be prepared to provide counselling on cannabis smoking cessation and inform the public and decision-makers.

Comparative genomics of flowering behavior in Cannabis sativa

Cannabis sativa L. is a phenotypically diverse and multi-use plant used in the production of fiber, seed, oils, and a class of specialized metabolites known as phytocannabinoids. The last decade has seen a rapid increase in the licit cultivation and processing of C. sativa for medical end-use. Medical morphotypes produce highly branched compact inflorescences which support a high density of glandular trichomes, specialized epidermal hair-like structures that are the site of phytocannabinoid biosynthesis and accumulation. While there is a focus on the regulation of phytocannabinoid pathways, the genetic determinants that govern flowering time and inflorescence structure in C. sativa are less well-defined but equally important. Understanding the molecular mechanisms that underly flowering behavior is key to maximizing phytocannabinoid production. The genetic basis of flowering regulation in C. sativa has been examined using genome-wide association studies, quantitative trait loci mapping and selection analysis, although the lack of a consistent reference genome has confounded attempts to directly compare candidate loci. Here we review the existing knowledge of flowering time control in C. sativa, and, using a common reference genome, we generate an integrated map. The co-location of known and putative flowering time loci within this resource will be essential to improve the understanding of C. sativa phenology.

Metabolomic analysis of methyl jasmonate treatment on phytocannabinoid production in Cannabis sativa

Cannabis sativa is a multi-use and chemically complex plant which is utilized for food, fiber, and medicine. Plants produce a class of psychoactive and medicinally important specialized metabolites referred to as phytocannabinoids (PCs). The phytohormone methyl jasmonate (MeJA) is a naturally occurring methyl ester of jasmonic acid and a product of oxylipin biosynthesis which initiates and regulates the biosynthesis of a broad range of specialized metabolites across a number of diverse plant lineages. While the effects of exogenous MeJA application on PC production has been reported, treatments have been constrained to a narrow molar range and to the targeted analysis of a small number of compounds. Using high-resolution mass spectrometry with data-dependent acquisition, we examined the global metabolomic effects of MeJA in C. sativa to explore oxylipin-mediated regulation of PC biosynthesis and accumulation. A dose-response relationship was observed, with an almost two-fold increase in PC content found in inflorescences of female clones treated with 15 mM MeJA compared to the control group. Comparison of the inflorescence metabolome across MeJA treatments coupled with targeted transcript analysis was used to elucidate key regulatory components contributing to PC production and metabolism more broadly. Revealing these biological signatures improves our understanding of the role of the oxylipin pathway in C. sativa and provides putative molecular targets for the metabolic engineering and optimization of chemical phenotype for medicinal and industrial end-uses.

Moving Away from 12:12; the Effect of Different Photoperiods on Biomass Yield and Cannabinoids in Medicinal Cannabis

The standard practice to initiate flowering in medicinal cannabis involves reducing the photoperiod from a long-day period to an equal duration cycle of 12 h light (12L)/12 h dark (12D). This method reflects the short-day flowering dependence of many cannabis varieties but may not be optimal for all. We sought to identify the effect of nine different flowering photoperiod treatments on the biomass yield and cannabinoid concentration of three medicinal cannabis varieties. The first, "Cannatonic", was a high cannabidiol (CBD)-accumulating line, whereas the other two, "Northern Lights" and "Hindu Kush", were high Δ9-tetrahydrocannabinol (THC) accumulators. The nine treatments tested, following 18 days under 18 h light/6 h dark following cloning and propagation included a standard 12L:12D period, a shortened period of 10L:14D, and a lengthened period of 14L:10D. The other six treatments started in one of the aforementioned and then 28 days later (mid-way through flowering) were switched to one of the other treatments, thus causing either an increase of 2 or 4 h, or a decrease of 2 or 4 h. Measured parameters included the timing of reproductive development; the dry weight flower yield; and the % dry weight of the main target cannabinoids, CBD and THC, from which the total g cannabinoid per plant was calculated. Flower biomass yields were highest for all lines when treatments started with 14L:10D; however, in the two THC lines, a static 14L:10D photoperiod caused a significant decline in THC concentration. Conversely, in Cannatonic, all treatments starting with 14L:10D led to a significant increase in the CBD concentration, which led to a 50-100% increase in total CBD yield. The results show that the assumption that a 12L:12D photoperiod is optimal for all lines is incorrect as, in some lines, yields can be greatly increased by a lengthened light period during flowering.

The Cannabis Plant as a Complex System: Interrelationships between Cannabinoid Compositions, Morphological, Physiological and Phenological Traits

Maintaining specific and reproducible cannabinoid compositions (type and quantity) is essential for the production of cannabis-based remedies that are therapeutically effective. The current study investigates factors that determine the plant's cannabinoid profile and examines interrelationships between plant features (growth rate, phenology and biomass), inflorescence morphology (size, shape and distribution) and cannabinoid content. An examination of differences in cannabinoid profile within genotypes revealed that across the cultivation facility, cannabinoids' qualitative traits (ratios between cannabinoid quantities) remain fairly stable, while quantitative traits (the absolute amount of Δ⁹-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabichromene (CBC), cannabigerol (CBG), Δ⁹-tetrahydrocannabivarin (THCV) and cannabidivarin (CBDV)) can significantly vary. The calculated broad-sense heritability values imply that cannabinoid composition will have a strong response to selection in comparison to the morphological and phenological traits of the plant and its inflorescences. Moreover, it is proposed that selection in favour of a vigorous growth rate, high-stature plants and wide inflorescences is expected to increase overall cannabinoid production. Finally, a range of physiological and phenological features was utilised for generating a successful model for the prediction of cannabinoid production. The holistic approach presented in the current study provides a better understanding of the interaction between the key features of the cannabis plant and facilitates the production of advanced plant-based medicinal substances.

The supply-side effects of cannabis legalization

Objective

The purpose of this study is to examine how cannabis legalization and corresponding taxation would affect the supply-side of the cannabis market. Specifically, the study considers various scenarios in which Oklahoma legalizes recreational cannabis for adult use and simulates changes in state-level market sales for other legal states and the average grower profits in Oklahoma. We assume that legalizing recreational cannabis in medical-only states would significantly increase the demand quantity in the legalized states and the local government would levy a significant level of tax on recreational cannabis. These assumptions are based on the post-legalization phenomena in other legalized US states.

Method

We simulate outcomes in the cannabis industry under the assumption of representative consumers with constant elasticity of substitution demand behavior and profit-maximizing firms with a Cobb-Douglas profit function. All agents are assumed to take exogenous prices as given. We calibrate the model using state-level sales data from 2020 and explore potential policies in Oklahoma and at the federal level.

Results

We find that, under the scenarios we consider, legalization of recreational cannabis in Oklahoma would lead to a decrease in the quantity of cannabis sold in Oklahoma’s medical cannabis market as well as decreases in the quantity of cannabis sold in other states on average. Furthermore, we find that as the excise tax rate on recreational cannabis in Oklahoma is increased, the demand quantity in recreational cannabis market would decrease while the other markets’ demand quantity would increase on average. As the elasticity of substitution between state-level products increases, the overall demand quantity would increase and the market quantity across states become more sensitive to Oklahoma’s tax policies. This pattern could become starker as the elasticity of substitution between recreational and medical cannabis increases. In terms of profit, heavy taxation and price decrease due to legalization would significantly decrease cannabis producers’ production and profit levels unless the cost reduction strategies complement legalization.

Conclusion

Based on our results, the legalization of recreational cannabis has the potential to generate tax revenue to fund critical government projects and services. However, such legalization would have to be done carefully because heavy excise taxes would decrease the legal cannabis market demand and growers’ profit, which would incentivize producers and consumers to move to the illicit cannabis market. Policymakers would have to compromise between the levels of interstate transportation and taxation to ensure that cannabis suppliers also realize some profit within the cannabis supply chain.

Cannabis Synthetic Seeds: An Alternative Approach for Commercial Scale of Clonal Propagation and Germplasm Conservation

Indoor cannabis (Cannabis sativa) cultivation has been rapidly increasing in many countries after legalization. Besides conventional propagation through cuttings, synthetic seed production provides a competent system for mass propagation, germplasm conservation and international exchange of genetic materials. The present study developed a reliable protocol for cannabis synthetic seed production using encapsulation of nodal segments derived from in vitro or in vivo sources. Synthetic seeds were produced in 3% sodium alginate and 75 mM calcium chloride in Murashige and Skoog (MS) medium and stored under various environmental conditions for up to 150 days. The plantlets regrowth efficiency was monitored on culture media up to 30 days after the storage period. Regrowth rates of 70% and 90% were observed in synthetic seeds from in vitro and in vivo-derived sources, respectively, when stored in 6 °C under 50 μmol s^-1 m^-2 light for 150 days. Furthermore, addition of acetylsalicylic acid (ASA) to the encapsulation matrix not only postponed precocious germination of synthetic seeds at 22 °C, but also improved the regrowth rate of in vivo-derived synthetic seeds to 100% when they were stored in 6 °C under light. Exposure to light during storage significantly increased shoot length of regrown synseeds when compared to those stored in darkness. This difference in shoot growth disappeared when synseeds were treated with 25 µM ASA. All regenerated plantlets were rooted and acclimatized in sterile rockwool plugs without morphological changes.

Review: Cannabinoids as Medicinals

PURPOSE OF REVIEW

There have been many debates, discussions, and published writings about the therapeutic value of cannabis plant and the hundreds of cannabinoids it contains. Many states and countries have attempted, are attempting, or have already passed bills to allow legal use of cannabinoids, especially cannabidiol (CBD), as medicines to treat a wide range of clinical conditions without having been approved by a regulatory body. Therefore, by using PubMed and Google Scholar databases, we have reviewed published papers during the past 30 years on cannabinoids as medicines and comment on whether there is sufficient clinical evidence from well-designed clinical studies and trials to support the use of CBD or any other cannabinoids as medicines.

RECENT FINDINGS

Current research shows that CBD and other cannabinoids currently are not ready for formal indications as medicines to treat a wide range of clinical conditions as promoted except for several exceptions including limited use of CBD for treating two rare forms of epilepsy in young children and CBD in combination with THC for treating multiple-sclerosis-associated spasticity.

SUMMARY

Research indicates that CBD and several other cannabinoids have potential to treat multiple clinical conditions, but more preclinical, and clinical studies and clinical trials, which follow regulatory guidelines, are needed to formally recommend CBD and other cannabinoids as medicines.

Review: Cannabinoids as Medicinals

Purpose of review

There have been many debates, discussions, and published writings about the therapeutic value of cannabis plant and the hundreds of cannabinoids it contains. Many states and countries have attempted, are attempting, or have already passed bills to allow legal use of cannabinoids, especially cannabidiol (CBD), as medicines to treat a wide range of clinical conditions without having been approved by a regulatory body. Therefore, by using PubMed and Google Scholar databases, we have reviewed published papers during the past 30 years on cannabinoids as medicines and comment on whether there is sufficient clinical evidence from well-designed clinical studies and trials to support the use of CBD or any other cannabinoids as medicines.

Recent findings

Current research shows that CBD and other cannabinoids currently are not ready for formal indications as medicines to treat a wide range of clinical conditions as promoted except for several exceptions including limited use of CBD for treating two rare forms of epilepsy in young children and CBD in combination with THC for treating multiple-sclerosis-associated spasticity.

Summary

Research indicates that CBD and several other cannabinoids have potential to treat multiple clinical conditions, but more preclinical, and clinical studies and clinical trials, which follow regulatory guidelines, are needed to formally recommend CBD and other cannabinoids as medicines.

Biosynthetic origins of unusual cannabimimetic phytocannabinoids in Cannabis sativa L: A review

Plants of Cannabis sativa L. (Cannabaceae) produce an array of more than 160 isoprenylated resorcinyl polyketides, commonly referred to as phytocannabinoids. These compounds represent molecules of therapeutic importance due to their modulation of the human endocannabinoid system (ECS). While understanding of the biosynthesis of the major phytocannabinoids Δ⁹-tetrahydrocannabinol (Δ⁹-THC) and cannabidiol (CBD) has grown rapidly in recent years, the biosynthetic origin and genetic regulation of many potentially therapeutically relevant minor phytocannabinoids remain unknown, which limits the development of chemotypically elite varieties of C. sativa. This review provides an up-to-date inventory of unusual phytocannabinoids which exhibit cannabimimetic-like activities and proposes putative metabolic origins. Metabolic branch points exploitable for combinatorial biosynthesis and engineering of phytocannabinoids with augmented therapeutic activities are also described, as is the role of phytocannabinoid remodelling to accelerate the therapeutic portfolio expansion in C. sativa.

Portable biosensors for rapid on-site determination of cannabinoids in cannabis, a review

Recent studies highlight the therapeutic virtues of cannabidiol (CBD). Furthermore, due to their molecular enriched profiles, cannabis inflorescences are biologically superior to a single cannabinoid for the treatment of various health conditions. Thus, there is flourishing demand for Cannabis sativa varieties containing high levels of CBD. Additionally, legal regulations around the world restrict the cultivation and consumption of tetrahydrocannabinol (THC)-rich cannabis plants for their psychotropic effects. Therefore, the use of cannabis varieties that are high in CBD is permitted as long as their THC content does not exceed a low threshold of 0.3%-0.5%, depending on the jurisdiction. These chemovars are legally termed 'hemp'. This controlled cannabinoid requirement highlights the need to detect low levels of THC, already in the field. In this review, cannabis profiling and the existing methods used for the detection of cannabinoids are firstly evaluated. Then, selected valuable biosensor technologies are discussed, which suggest portable, rapid, sensitive, reproducible, and reliable methods for on-site identification of cannabinoids levels, mainly THC. Recent cutting-edge techniques of promising potential usage for both cannabis and hemp analysis are identified, as part of the future cultivation and agricultural improvement of this crop.

Understanding Cannabis sativa L.: Current Status of Propagation, Use, Legalization, and Haploid-Inducer-Mediated Genetic Engineering

Cannabis sativa L. is an illegal plant in many countries. The worldwide criminalization of the plant has for many years limited its research. Consequently, understanding the full scope of its benefits and harm became limited too. However, in recent years the world has witnessed an increased pace in legalization and decriminalization of C. sativa. This has prompted an increase in scientific studies on various aspects of the plant’s growth, development, and use. This review brings together the historical and current information about the plant’s relationship with mankind. We highlight the important aspects of C. sativa classification and identification, carefully analyzing the supporting arguments for both monotypic (single species) and polytypic (multiple species) perspectives. The review also identifies recent studies on suitable conditions and methods for C. sativa propagation as well as highlighting the diverse uses of the plant. Specifically, we describe the beneficial and harmful effects of the prominent phytocannabinoids and provide status of the studies on heterologous synthesis of phytocannabinoids in different biological systems. With a historical view on C. sativa legality, the review also provides an up-to-date worldwide standpoint on its regulation. Finally, we present a summary of the studies on genome editing and suggest areas for future research.

Growing ganja permission: a real gate-way for Thailand's promising industrial crop?

The current revision to Thailand’s Narcotics Act (B.E. 2563) permits Thai corporations to produce cannabis (ganja) for therapeutic purposes, as well as conduct beneficial research and development in science and agriculture. While ganja possession, distribution, and use are still illegal in Thailand, the law removes certain elements of Cannabis sativa (including hemp) from the narcotic lists as of December 2020 and Thailand's narcotics board plans to remove them totally from the lists before the last quarter of 2022. The Thai Food and Drug Administration (Thai FDA) board maintains the exclusive licensing authority to assess applications and provide authorization due to the complexity of the registration process. In this view, we analyzed the guidelines for obtaining cannabis production license, and it was apparent that the announced law was in-line with regulations set-out by many countries in terms of security and prevention of misuse. The other criteria however fall merely onto the government gains, rather than public interests. To avoid the claimed state monopoly, several types of licensing should be issued in the future, depending on the genuine purpose of the farmers. The complete regulation process and conditions for obtaining a ganja growing license in Thailand are highlighted and discussed in this review.

Post-Harvest Operations to Generate High-Quality Medicinal Cannabis Products: A Systemic Review

The traditional Cannabis plant as a medicinal crop has been explored for many thousands of years. The Cannabis industry is rapidly growing; therefore, optimising drying methods and producing high-quality medical products have been a hot topic in recent years. We systemically analysed the current literature and drew a critical summary of the drying methods implemented thus far to preserve the quality of bioactive compounds from medicinal Cannabis. Different drying techniques have been one of the focal points during the post-harvesting operations, as drying preserves these Cannabis products with increased shelf life. We followed or even highlighted the most popular methods used. Drying methods have advanced from traditional hot air and oven drying methods to microwave-assisted hot air drying or freeze-drying. In this review, traditional and modern drying technologies are reviewed. Each technology will have different pros and cons of its own. Moreover, this review outlines the quality of the Cannabis plant component harvested plays a major role in drying efficiency and preserving the chemical constituents. The emergence of medical Cannabis, and cannabinoid research requires optimal post-harvesting processes for different Cannabis strains. We proposed the most suitable method for drying medicinal Cannabis to produce consistent, reliable and potent medicinal Cannabis. In addition, drying temperature, rate of drying, mode and storage conditions after drying influenced the Cannabis component retention and quality.

Future Directions for the Discovery of Natural Product-Derived Immunomodulating Drugs

Drug discovery from natural sources is going through a renaissance, having spent many decades in the shadow of synthetic molecule drug discovery, despite the fact that natural product-derived compounds occupy a much greater chemical space than those created through synthetic chemistry methods. With this new era comes new possibilities, not least the novel targets that have emerged in recent times and the development of state-of-the-art technologies that can be applied to drug discovery from natural sources. Although progress has been made with some immunomodulating drugs, there remains a pressing need for new agents that can be used to treat the wide variety of conditions that arise from disruption, or over-activation, of the immune system; natural products may therefore be key in filling this gap. Recognising that, at present, there is no authoritative article that details the current state-of-the-art of the immunomodulatory activity of natural products, this in-depth review has arisen from a joint effort between the International Union of Basic and Clinical Pharmacology (IUPHAR) Natural Products and Immunopharmacology, with contributions from a Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation number of world-leading researchers in the field of natural product drug discovery, to provide a "position statement" on what natural products has to offer in the search for new immunomodulatory argents. To this end, we provide a historical look at previous discoveries of naturally occurring immunomodulators, present a picture of the current status of the field and provide insight into the future opportunities and challenges for the discovery of new drugs to treat immune-related diseases.

Optimizing Photoperiod Switch to Maximize Floral Biomass and Cannabinoid Yield in Cannabis sativa L.: A Meta-Analytic Quantile Regression Approach

Cannabis sativa L. is an annual, short-day plant, such that long-day lighting promotes vegetative growth while short-day lighting induces flowering. To date, there has been no substantial investigation on how the switch between these photoperiods influences yield of C. sativa despite the tight correlation that plant size and floral biomass have with the timing of photoperiod switches in indoor growing facilities worldwide. Moreover, there are only casual predictions around how the timing of the photoperiodic switch may affect the production of secondary metabolites, like cannabinoids. Here we use a meta-analytic approach to determine when growers should switch photoperiods to optimize C. sativa floral biomass and cannabinoid content. To this end, we searched through ISI Web of Science for peer-reviewed publications of C. sativa that reported experimental photoperiod durations and results containing cannabinoid concentrations and/or floral biomass, then from 26 studies, we estimated the relationship between photoperiod and yield using quantile regression. Floral biomass was maximized when the long daylength photoperiod was minimized (i.e., 14 days), while THC and CBD potency was maximized under long day length photoperiod for ~42 and 49-50 days, respectively. Our work reveals a yield trade-off in C. sativa between cannabinoid concentration and floral biomass where more time spent under long-day lighting maximizes cannabinoid content and less time spent under long-day lighting maximizes floral biomass. Growers should carefully consider the length of long-day lighting exposure as it can be used as a tool to maximize desired yield outcomes.

Impact of Harvest Time and Pruning Technique on Total CBD Concentration and Yield of Medicinal Cannabis

The definition of optimum harvest and pruning interventions are important factors varying inflorescence yield and cannabinoid composition. This study investigated the impact of (i) harvest time (HT) and (ii) pruning techniques (PT) on plant biomass accumulation, CBD and CBDA-concentrations and total CBD yield of a chemotype III medical cannabis genotype under indoor cultivation. The experiment consisted of four HTs between 5 and 11 weeks of flowering and three PTs-apical cut (T); removal of side shoots (L) and control (C), not pruned plants. Results showed that inflorescence dry weight increased continuously, while the total CBD concentration did not differ significantly over time. For the studied genotype, optimum harvest time defined by highest total CBD yield was found at 9 weeks of flowering. Total CBD-concentration of inflorescences in different fractions of the plant's height was significantly higher in the top (9.9%) in comparison with mid (8.2%) and low (7.7%) fractions. The T plants produced significantly higher dry weight of inflorescences and leaves than L and C. Total CBD yield of inflorescences for PTs were significantly different among pruned groups, but do not differ from the control group. However, a trend for higher yields was observed (T > C > L).

The Effect of Cannabis-Based Medicine in the Treatment of Cachexia: A Systematic Review and Meta-Analysis

Background: Cachexia is a prevalent condition associated with underlying chronic disease. Wasting of skeletal muscle and adipose tissue loss in cachectic patients is associated with higher rates of disability, reduced quality of life (QoL), and worse prognosis. There is a large unmet need to develop strategies to treat cachexia as there are currently no standardized guidelines in the management of cachexia. Activation of endogenous cannabinoid receptors, through exogenous cannabinoids, has demonstrated potential in increasing appetite, reducing catabolism, and has shown anti-inflammatory properties. Since no single pharmacological agent is currently recommended for use in cachexia, the potential of cannabinoids as an appetite stimulant warrants further research and assessment of current evidence. Objective: This review aims to evaluate the evidence for the efficacy of cannabis-based medicinal products, against placebo and other active treatments, in anorexia-cachexia syndrome in improving appetite, weight, and QoL. Methods: A literature search of the Medline, EMBASE, CENTRAL, and the Web of Science Core Collection, for articles published up to February 2020, was conducted. All randomized controlled trials comparing the use of cannabis-based medicine versus placebo/active treatments for patients with cachexia were screened. The quality of evidence in included studies was assessed using the GRADE framework and any risk of bias was judged using the Cochrane risk of bias tool. Results: A total of five studies, encompassing 934 participants, were found to be eligible. The pooled group effect size for change in appetite was -1.79 (95% confidence interval: -3.77 to 0.19) favoring the control group (p=0.08). Additionally, no significant difference for weight change or change in QoL for cannabinoids versus placebo/other treatment was observed. The quality of evidence for all five studies was assessed to be low. Conclusion: There is a lack of high-quality evidence to recommend the use of cannabinoids in the treatment of cachexia. Given the limited available pharmacological options for cachexia and the potential for cannabinoids to increase appetite and alter the immune system, further research is needed before clinical recommendations on the pharmacological management of cachexia can be made.

Contents of Cannabinoids in Hemp Varieties Grown in Maryland

Coincident with the cannabis legalization and the increased interest in the medicinal use of the plant, the cannabis marketplace and farming have seen tremendous growth. It is reported that there are more than 2000 cannabis varieties available to customers. However, the data that is available to the growers and breeders regarding the cannabinoid contents of various varieties remains low. Here, a high-performance liquid chromatography (HPLC) method was developed and validated for the simultaneous separation and determination of 11 cannabinoids. A total of 104 hemp bud materials belonging to 20 varieties were collected from farms in the state of Maryland and analyzed with the HPLC method. The contents of the 11 cannabinoids in various varieties were compared and discussed, highlighting the varieties that showed a high yield of cannabinoids and good consistency that are more appropriate for cannabinoid production.

Forensic laboratory backlog: The impact of inconclusive results of marijuana analysis and the implication on analytical routine

Forensic laboratories worldwide are struggling to keep up with the increasing number of cases submitted for analysis, regardless of the reasons, backlog of controlled substances cases is a reality in many countries. In this paper we analyse the number of petitioned examinations (from 2016 to 2020) and the data from 11,655 marijuana TLC results from the Forensic Laboratory in the Federal District Civil Police in Brazil. Data demonstrates that backlog increases inconclusive results, with storage and light playing a crucial role in the process. Additionally we explored the repercussions of delayed forensic results for controlled substances and propose an approach to overcome waiting time in this context.

Cannabidiol modulation of oxidative stress and signalling

Cannabidiol (CBD), one of the primary non-euphoric components in the Cannabis sativa L. plant, has undergone clinical development over the last number of years as a therapeutic for patients with Lennox-Gastaut syndrome and Dravet syndromes. This phytocannabinoid demonstrates functional and pharmacological diversity, and research data indicate that CBD is a comparable antioxidant to common antioxidants. This review gathers the latest knowledge regarding the impact of CBD on oxidative signalling, with focus on the proclivity of CBD to regulate antioxidants and control the production of reactive oxygen species. CBD is considered an attractive therapeutic agent for neuroimmune disorders, and a body of literature indicates that CBD can regulate redox function at multiple levels, with a range of downstream effects on cells and tissues. However, pro-oxidant capacity of CBD has also been reported, and hence caution must be applied when considering CBD from a therapeutic standpoint. Such pro- and antioxidant functions of CBD may be cell- and model-dependent and may also be influenced by CBD dose, the duration of CBD treatment and the underlying pathology.

Impact of Three Different Light Spectra on the Yield, Morphology and Growth Trajectory of Three Different Cannabis sativa L. Strains

Cannabis is one of the oldest cultivated plants, but plant breeding and cultivation are restricted by country specific regulations. Plant growth, morphology and metabolism can be manipulated by changing light quality and intensity. Three morphologically different strains were grown under three different light spectra with three real light repetitions. Light dispersion was included into the statistical evaluation. The light spectra considered had an influence on the morphology of the plant, especially the height. Here, the shade avoidance induced by the lower R:FR ratio under the ceramic metal halide lamp (CHD) was of particular interest. The sugar leaves seemed to be of elementary importance in the last growth phase for yield composition. Furthermore, the last four weeks of flowering were crucial to influence the yield composition of Cannabis sativa L. through light spectra. The dry flower yield was significantly higher under both LED treatments compared to the conventional CHD light source. Our results indicate that the plant morphology can be artificially manipulated by the choice of light treatment to create shorter plants with more lateral branches which seem to be beneficial for yield development. Furthermore, the choice of cultivar has to be taken into account when interpreting results of light studies, as Cannabis sativa L. subspecies and thus bred strains highly differ in their phenotypic characteristics.

Development and early identification of Cannabis chemotypes during the plant growth: current analytical and chemometric approaches

The identification of cannabis chemotypes at an early stage of a plant's growth, which is long before anthesis, has been intensively pursued in order to control the on-target selection of the cultivar type at the beginning of cultivation, so as to avoid economic and legal drawbacks. However, this issue has been systematically addressed by only few and relatively recent studies of analytical chemistry, possibly because result validations require long-term monitoring of the content and ratio of cannabinoids and terpenes in a great number of plant specimens suitably selected and grown. Here, we review the procedures, the chromatographic techniques and the statistics used in topical investigations during the past thirteen years. Through heterogeneous and not easily comparable approaches, they prove the feasibility of chemotypes safe determination within the first month of a plant's life.

The characterization of key physiological traits of medicinal cannabis (Cannabis sativa L.) as a tool for precision breeding

BACKGROUND

For millennia, drug-type cannabis strains were extensively used for various medicinal, ritual, and inebriant applications. However, cannabis prohibition during the last century led to cultivation and breeding activities being conducted under clandestine conditions, while scientific development of the crop ceased. Recently, the potential of medicinal cannabis has been reacknowledged and the now expanding industry requires optimal and scientifically characterized varieties. However, scientific knowledge that can propel this advancement is sorely lacking. To address this issue, the current study aims to provide a better understanding of key physiological and phenological traits that can facilitate the breeding of advanced cultivars.

RESULTS

A diverse population of 121 genotypes of high-THC or balanced THC-CBD ratio was cultivated under a controlled environment facility and 13 plant parameters were measured. No physiological association across genotypes attributed to the same vernacular classification was observed. Floral bud dry weight was found to be positively associated with plant height and stem diameter but not with days to maturation. Furthermore, the heritability of both plant height and days to maturation was relatively high, but for plant height it decreased during the vegetative growth phase. To advance breeding efficacy, a prediction equation for forecasting floral bud dry weight was generated, driven by parameters that can be detected during the vegetative growth phase solely.

CONCLUSIONS

Our findings suggest that selection for taller and fast-growing genotypes is likely to lead to an increase in floral bud productivity. It was also found that the final plant height and stem diameter are determined by 5 independent factors that can be used to maximize productivity through cultivation adjustments. The proposed prediction equation can facilitate the selection of prolific genotypes without the completion of a full cultivation cycle. Future studies that will associate genome-wide variation with plants morphological traits and cannabinoid profile will enable precise and accelerated breeding through genomic selection approaches.

Metabolomic Analysis of Cannabinoid and Essential Oil Profiles in Different Hemp (Cannabis sativa L.) Phenotypes

Hemp (Cannabis sativa L.) cannabinoids and terpenoids have therapeutic effects on human and animal health. Cannabis plants can often have a relatively high heterogeneity, which leads to different phenotypes that have different chemical profiles despite being from the same variety. Little information exists about cannabinoid and terpenoid profiles in different hemp phenotypes within the same variety. For this study, 11 phenotypes from three different varieties (“Carmagnola” selected (CS), “Tiborszallasi” (TS), and “Finola” selection (FS)) were analyzed. The components of essential oil (29) were analyzed using gas chromatography with flame ionization detection (GC/FID), and 10 different cannabinoids of each phenotype were determined using high-performance liquid chromatography (HPLC). Principal component analysis (PCA) and analysis of variance (ANOVA) showed that according to the components of essential oil, FS and TS plants were more uniform than CS plants, where there were great differences between CI and CII phenotypes. The content of cannabinoid CBD-A was the highest in all four FS phenotypes. By comparing cannabinoid profiles, FS was clearly separated from TS and CS, while these two varieties were not clearly distinguishable. Phenotypes TV and CI had the highest total content of Δ-9-THC, while all phenotypes of FS had the highest total content of CBD. The highest total content of CBG was determined in phenotype CI. Obtained results are useful for the development of new supplementary ingredients, for different pharmacy treatments, and for further breeding purposes.

Repurposing Cannabidiol as a Potential Drug Candidate for Anti-Tumor Therapies

In recent years, evidence has accumulated that cannabinoids-especially the non-psychoactive compound, cannabidiol (CBD)-possess promising medical and pharmacological activities that might qualify them as potential anti-tumor drugs. This review is based on multiple studies summarizing different mechanisms for how CBD can target tumor cells including cannabinoid receptors or other constituents of the endocannabinoid system, and their complex activation of biological systems that results in the inhibition of tumor growth. CBD also participates in anti-inflammatory activities which are related to tumor progression, as demonstrated in preclinical models. Although the numbers of clinical trials and tested tumor entities are limited, there is clear evidence that CBD has anti-tumor efficacy and is well tolerated in human cancer patients. In summary, it appears that CBD has potential as a neoadjuvant and/or adjuvant drug in therapy for cancer.

A Rapid Nano-Liquid Chromatographic Method for the Analysis of Cannabinoids in Cannabis sativa L. Extracts

Cannabis sativa L. is an herbaceous plant belonging to the family of Cannabaceae. It is classified into three different chemotypes based on the different cannabinoids profile. In particular, fiber-type cannabis (hemp) is rich in cannabidiol (CBD) content. In the present work, a rapid nano liquid chromatographic method (nano-LC) was proposed for the determination of the main cannabinoids in Cannabis sativa L. (hemp) inflorescences belonging to different varieties. The nano-LC experiments were carried out in a 100 µm internal diameter capillary column packed with a C18 stationary phase for 15 cm with a mobile phase composed of ACN/H₂O/formic acid, 80/19/1% (v/v/v). The reverse-phase nano-LC method allowed the complete separation of four standard cannabinoids in less than 12 min under isocratic elution mode. The nano-LC method coupled to ultraviolet (UV) detection was validated and applied to the quantification of the target analytes in cannabis extracts. The nano-LC system was also coupled to an electrospray ionization–mass spectrometry (ESI-MS) detector to confirm the identity of the cannabinoids present in hemp samples. For the extraction of the cannabinoids, three different approaches, including dynamic maceration (DM), ultrasound-assisted extraction (UAE), and an extraction procedure adapted from the French Pharmacopeia’s protocol on medicinal plants, were carried out, and the results achieved were compared.

Cannabis lighting: Decreasing blue photon fraction increases yield but efficacy is more important for cost effective production of cannabinoids

LED technology facilitates a range of spectral quality, which can be used to optimize photosynthesis, plant shape and secondary metabolism. We conducted three studies to investigate the effect of blue photon fraction on yield and quality of medical hemp. Conditions were varied among studies to evaluate potential interactions with environment, but all environmental conditions other than the blue photon fraction were maintained constant among the five-chambers in each study. The photosynthetic photon flux density (PPFD, 400 to 700 nm) was rigorously maintained at the set point among treatments in each study by raising the fixtures. The lowest fraction of blue photons was 4% from HPS, and increased to 9.8, 10.4, 16, and 20% from LEDs. There was a consistent, linear, 12% decrease in yield in each study as the fraction of blue photons increased from 4 to 20%. Dry flower yield ranged from 500 to 750 g m-2. This resulted in a photon conversion efficacy of 0.22 to 0.36 grams dry flower mass yield per mole of photons. Yield was higher at a PPFD of 900 than at 750 μmol m-2 s-1. There was no effect of spectral quality on CBD or THC concentration. CBD and THC were 8% and 0.3% at harvest in trials one and two, and 12% and 0.5% in trial three. The CBD/THC ratio was about 25 to 1 in all treatments and studies. The efficacy of the fixtures ranged from 1.7 (HPS) to 2.5 μmol per joule (white+red LED). Yield under the white+red LED fixture (10.4% blue) was 4.6% lower than the HPS on a per unit area basis, but was 27% higher on a per dollar of electricity basis. These findings suggest that fixture efficacy and initial cost of the fixture are more important for return on investment than spectral distribution at high photon flux.

Untargeted Metabolomic Analyses Reveal Chemical Complexity of Dioecious Cannabis Flowers

Cannabis is a mostly dioecious multi-use flowering plant genus. Sexual dimorphism is an important characteristic in Cannabis-based commercial production systems, which has consequences for fibre, seed, and the yield of secondary metabolites, such as phytocannabinoid and terpenes for therapeutic uses. Beyond the obvious morphological differences between male and female plants, metabolic variation among dioecious flowers is largely undefined. Here, we report a pilot metabolomic study comparing staminate (male) and pistillate (female) unisexual flowers. Enrichment of the α-linolenic acid pathway and consensus evaluation of the jasmonic acid (JA) related compound 12-oxo-phytodienoicacid (OPDA) among differentially abundant metabolites suggests that oxylipin signalling is associated with secondary metabolism and sex expression in female flowers. Several putative phytocannabinoid-like compounds were observed to be upregulated in female flowers, but full identification was not possible due to the limitation of available databases. Targeted analysis of 14 phytocannabinoids using certified reference standards (cannabidiolic acid (CBDA), cannabidiol (CBD), Δ9-tetrahydrocannabinolic acid A (Δ9-THCAA), Δ9-tetrahydrocannabinol (Δ9-THC), cannabichromenic acid (CBCA), cannabichromene (CBC), cannabigerolic acid (CBGA), cannabigerol (CBG), cannabinolic acid (CBNA), cannabinol (CBN), cannabidivarinic acid (CBDVA), cannabidivarin (CBDV), tetrahydrocannabivarinic acid (THCVA), and tetrahydrocannabivarin (THCV)) showed a higher total phytocannabinoid content in female flowers compared with the male flowers, as expected. In summary, the development of a phytocannabinoid-specific accurate-mass MSn fragmentation spectral library and gene pool representative metabolome has the potential to improve small molecule compound annotation and accelerate understanding of metabolic variation underlying phenotypic diversity in Cannabis.

‘Cannabis’ ontologies I: Conceptual issues with Cannabis and cannabinoids terminology

Objective

Identify a coherent nomenclature for Cannabis sativa L. derived products and their analogues.

Design

Research undertaken in parallel to the three-year assessment of Cannabis derivatives by the World Health Organisation. The scope is limited to Cannabis products intended for human incorporation (internal and topical consumption). Primarily embedded in pharmacognosy, the study incorporates a wide range of scholarly and grey literature, folk knowledge, archives, pharmacopœias, international law, field pharmacy, clinical and herbal medicine data, under a philosophical scrutiny. Generic and Cannabis-specific nomenclatural frames are compared to determine the extent to which they coincide or conflict.

Results

All lexica reviewed use weak, ambiguous, or inconsistent terms. There is insufficient scientific basis for terms and concepts related to Cannabis at all levels. No sound classification exists: current models conflict by adopting idiosyncratic, partial, outdated, or utilitarian schemes to arrange the extraordinarily numerous and diverse derivatives of the C. sativa plant. In law and policy, no clear or unequivocal boundary between herbal and non-herbal drugs, nor natural and synthetic cannabinoids was found; current nomenclatures need updates. In science, the botanical Cannabis lexicon overlooks parthenocarpy, and wide disagreement remains as to the taxonomy and systematics of the plant; chemical research should address differences in kinds between synthetic cannabinoids; pharmacopœias include little information related to Cannabis, and disagree on broader classes of herbal medicines, virtually failing to embrace many known Cannabis medicines. Since existing products and compounds fail to be categorised in an evidence-based manner, confusions will likely increase as novel cannabinoid compounds, genetic and biotechnological modifications surge.

Conclusions

The lack of clarity is comprehensive: for patients, physicians, and regulators. This study proposes an update of terms at several levels. It points at gaps in morphological descriptions in botany and pharmacognosy and a need for a metaphysical address of cannabinoids. Methods of obtention are identified as a common criterion to distinguish products; the way forward suggests a mutually exclusive nomenclatural pattern based on the smallest common denominator of obtention methods. In the context of a swelling number of Cannabis products being consumed (be it via medical prescription, adult-use, ‘hemp’ foodstuff and cosmetics, or other purposes), this study can assist research, contribute to transparent labelling of products, consumer safety and awareness, pharmacovigilance, medical standards of care, and an update of prevention and harm reduction approaches. It can also better inform regulatory policies surrounding C. sativa, its derivatives, and other cannabinoid-containing products.

An extreme-phenotype genome-wide association study identifies candidate cannabinoid pathway genes in Cannabis

Cannabis produces a class of isoprenylated resorcinyl polyketides known as cannabinoids, a subset of which are medically important and exclusive to this plant. The cannabinoid alkyl group is a critical structural feature that governs therapeutic activity. Genetic enhancement of the alkyl side-chain could lead to the development of novel chemical phenotypes (chemotypes) for pharmaceutical end-use. However, the genetic determinants underlying in planta variation of cannabinoid alkyl side-chain length remain uncharacterised. Using a diversity panel derived from the Ecofibre Cannabis germplasm collection, an extreme-phenotype genome-wide association study (XP-GWAS) was used to enrich for alkyl cannabinoid polymorphic regions. Resequencing of chemotypically extreme pools revealed a known cannabinoid synthesis pathway locus as well as a series of chemotype-associated genomic regions. One of these regions contained a candidate gene encoding a β-keto acyl carrier protein (ACP) reductase (BKR) putatively associated with polyketide fatty acid starter unit synthesis and alkyl side-chain length. Association analysis revealed twenty-two polymorphic variants spanning the length of this gene, including two nonsynonymous substitutions. The success of this first reported application of XP-GWAS for an obligate outcrossing and highly heterozygote plant genus suggests that this approach may have generic application for other plant species.

Cannabis Chemovar Nomenclature Misrepresents Chemical and Genetic Diversity; Survey of Variations in Chemical Profiles and Genetic Markers in Nevada Medical Cannabis Samples

Introduction: Medical cannabis patients receive clinical benefits from the secondary metabolites of the plant, which contain a variety of cannabinoids and terpenoids in combinations that can be used to classify the chemovars. State-regulated medical cannabis programs rely on breeder-reported “strain” names both within diversion control systems and to describe the medical cannabis products that are sold to patients in medical cannabis dispensaries. In state-regulated medical cannabis programs, there is no conventional nomenclature system that correlates the breeder-reported names with their profiles of active ingredients, and these “strain” names are invalid as they refer to chemical differences properly referred to as to chemovars.

Materials and Methods: To determine the actual levels of chemical diversity represented in 2662 samples of Cannabis flower collected between January 2016 and June of 2017 in Nevada, chemical profile data were measured from these samples by a state-qualified third-party testing laboratory. Principal component analysis (PCA) was used to define clusters in data sets representing both cannabinoids and terpenoids, cannabinoids only, or terpenoids only.

Results: The PCA of the terpenoid only data set revealed three well-defined clusters. All three terpenoids only data clusters had high tetrahydrocannabinolic acid synthase, but the terpene profiles listed in reverse-order of abundance best defined these chemovars. The three chemovars in Nevada were labeled with 396 breeder-reported sample names, which overestimate the diversity and do not inform patients regarding chemical properties. Representative DNA samples were taken from each chemovar to determine whether the genetic diversity was greater than the chemical diversity. The limited genotyping experiment was based on DNA sequence polymorphisms. The genetic analysis revealed twelve distinct genetic clades, which still does not account for the entirety of the 396 reported sample names. The finite genotypes did not correlate with the chemotypes determined for the samples. This suggests that either the DNA-markers used were too narrowly restricted for factual separation or that environmental factors contributed more significantly to the chemical profiles of cannabis than genetics.

Conclusion: The three chemovars and twelve genotypes reflect low medical diversity on the market in Nevada during its “medical use only” phase. Furthermore, the 396 breeder-reported sample names within this set imply a false sense of diversity of products in Nevada dispensaries.

Different Effects of Cannabis Abuse on Adolescent and Adult Brain

Cannabis abuse is a common phenomenon among adolescents. The dominant psychoactive substance in Cannabis sativa is tetrahydrocannabinol (THC). However, in the past 40 years the content of the psychoactive ingredient THC in most of the preparations is not constant but has increased due to other breeding and culturing conditions. THC acts as the endocannabinoids at CB1 and CB2 receptors but pharmacologically can be described as a partial (not a pure) agonist. Recent evidence shows that activation of the CB1 receptor by THC can diminish the production of neuronal growth factor in neurons and affect other signalling cascades involved in synapsis formation. Since these factors play an important role in the brain development and in the neuronal conversion processes during puberty, it seems reasonable that THC can affect the adolescent brain in another manner than the adult brain. Accordingly, in adolescent cannabis users structural changes were observed with loss of grey matter in certain brain areas. Moreover, recent studies show different effects of THC on adolescent and adult brains and on behaviour. These studies indicate that early THC abuse can result in neuropsychological deficits. This review gives an overview over the present knowledge in this field.

Cannabis sativa L. Inflorescences from Monoecious Cultivars Grown in Central Italy: An Untargeted Chemical Characterization from Early Flowering to Ripening

The chemical composition of the inflorescences from four Cannabis sativa L. monoecious cultivars (Ferimon, Uso-31, Felina 32 and Fedora 17), recently introduced in the Lazio Region, was monitored over the season from June to September giving indications on their sensorial, pharmaceutical/nutraceutical proprieties. Both untargeted (NMR) and targeted (GC/MS, UHPLC, HPLC-PDA/FD and spectrophotometry) analyses were carried out to identify and quantify compounds of different classes (sugars, organic acids, amino acids, cannabinoids, terpenoids, phenols, tannins, flavonoids and biogenic amines). All cultivars in each harvesting period showed a THC content below the Italian legal limit, although in general THC content increased over the season. Citric acid, malic acid and glucose showed the highest content in the late flowering period, whereas the content of proline drastically decreased after June in all cultivars. Neophytadiene, nerolidol and chlorogenic acid were quantified only in Felina 32 cultivar, characterized also by a very high content of flavonoids, whereas alloaromadendrene and trans-cinnamic acid were detected only in Uso-31 cultivar. Naringenin and naringin were present only in Fedora 17 and Ferimon cultivars, respectively. Moreover, Ferimon had the highest concentration of biogenic amines, especially in July and August. Cadaverine was present in all cultivars but only in September. These results suggest that the chemical composition of Cannabis sativa L. inflorescences depends on the cultivar and on the harvesting period. Producers can use this information as a guide to obtain inflorescences with peculiar chemical characteristics according to the specific use.

Spatio-Temporal and Cultivar-Dependent Variations in the Cannabis Microbiome

The incipient legalization and commercialization of Cannabis sativa in Canada have promulgated research into characterizing the plant’s microbiome as it promotes many facets of plant growth and health. The emblematic production of commercially important secondary metabolites, namely tetrahydrocannabinol (THC), cannabidiol (CBD) and terpenes, has warranted investigating the modulating capacity of these molecules on the plant microbiome. C. sativa cultivars can be classified into chemotypes depending on the relative levels of THC and CBD they produce; their biosynthesis also varies spatially and temporally during the life cycle of the plant. To study the differential microbiome structure and diversity between cultivars in a spatio-temporal manner, we extracted microbial DNA from the rhizosphere, endorhizosphere, and phyllosphere during the entire life cycle of three different chemotypes; CBD Yummy (<1% THC/13% CBD), CBD shark (6% THC/10% CBD) and Hash (14% THC/ < 1% CBD). Illumina marker gene sequencing of bacterial (16S) and fungal (ITS) communities were coupled to the QIIME2, PICRUSt, and LEfSe pipelines for analysis. Our study describes spatio-temporal and cultivar-dependent variations in the fungal and bacterial microbiome of C. sativa, and details strong cultivar-dependent variance in the belowground microbiome. Furthermore, the predicted pathway abundance of the bacterial microbiome is concomitantly subject to spatio-temporal variations; pathways related to lipid, amino acid, glucose and pentose metabolism were noteworthy. These results describe, for the first time, spatio-temporal and cultivar-dependent variations in the microbiome of C. sativa produced under strict commercial settings. Describing the microbiome is the first step in discoveries that could help in engineering a plant growth and health promoting microbiome in future works.

Investigating Relationships Between Alcohol and Cannabis Use in an Online Survey of Cannabis Users: A Focus on Cannabinoid Content and Cannabis for Medical Purposes

Cannabis is commonly used among people who drink alcohol, but findings are mixed regarding the direction of this relationship. The type of cannabis used [high-cannabidiol (CBD) vs. high-delta-9tetrahydrocannabinol (THC)] and motives for use (i.e., whether cannabis is used to treat a medical condition) may influence the relationship between cannabis and drinking. Specifically, CBD has shown preclinical promise in reducing alcohol consumption, and medical cannabis users report using cannabis to reduce drinking. This study leverages survey data from cannabis users who drink alcohol (N = 533). Respondents were categorized as using cannabis to treat (CTT) a medical condition or as individuals whose cannabis use is not intended to treat (NCTT) a medical condition and grouped based on the THC/CBD ratio of the flower or edible cannabis they typically use (e.g., "High-THC/CBD," "Medium-THC/CBD" and "Low-THC/CBD"). The CTT group (n = 412) reported drinking significantly less frequently than the NCTT group (n = 121). Cannabinoid content of flower cannabis was associated with alcohol consumed on cannabis-use days, such that individuals in the High-THC/CBD group drink more on cannabis-use days compared to the Medium-THC/CBD group. Cannabinoid content of edible cannabis was associated with drinks per drinking occasion, such that the High-THC/CBD group consumed the most drinks and the Low-THC/CBD group consumed the fewest. For both edible and flower groupings, higher-THC/CBD cannabis was associated with more frequent co-use than lower-THC/CBD cannabis. Results suggest that whether someone uses cannabis to treat a medical condition may impact their drinking frequency, and the cannabinoid content in flower and edible cannabis impacts alcohol consumption.

Cannabidiol-from Plant to Human Body: A Promising Bioactive Molecule with Multi-Target Effects in Cancer

Cannabis sativa L. is a plant long used for its textile fibers, seed oil, and oleoresin with medicinal and psychoactive properties. It is the main source of phytocannabinoids, with over 100 compounds detected so far. In recent years, a lot of attention has been given to the main phytochemicals present in Cannabis sativa L., namely, cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC). Compared to THC, CBD has non-psychoactive effects, an advantage for clinical applications of anti-tumor benefits. The review is designed to provide an update regarding the multi-target effects of CBD in different types of cancer. The main focus is on the latest in vitro and in vivo studies that present data regarding the anti-proliferative, pro-apoptotic, cytotoxic, anti-invasive, anti-antiangiogenic, anti-inflammatory, and immunomodulatory properties of CBD together with their mechanisms of action. The latest clinical evidence of the anticancer effects of CBD is also outlined. Moreover, the main aspects of the pharmacological and toxicological profiles are given.