Cell Suspensions of Cannabis sativa (var. Futura): Effect of Elicitation on Metabolite Content and Antioxidant Activity

Phytochemical Composition and Antioxidant Activity of Various Extracts of Fibre Hemp (Cannabis sativa L.) Cultivated in Lithuania

The phytochemistry of fibre hemp (Cannabis sativa L., cv. Futura 75 and Felina 32) cultivated in Lithuania was investigated. The soil characteristics (conductivity, pH and major elements) of the cultivation field were determined. The chemical composition of hemp extracts and essential oils (EOs) from different plant parts was determined by the HPLC/DAD/TOF and GC/MS techniques. Among the major constituents, β-caryophyllene (≤46.64%) and its oxide (≤14.53%), α-pinene (≤20.25%) or α-humulene (≤11.48) were determined in EOs. Cannabidiol (CBD) was a predominant compound (≤64.56%) among the volatile constituents of the methanolic extracts of hemp leaves and inflorescences. Appreciable quantities of 2-monolinolein (11.31%), methyl eicosatetraenoate (9.70%) and γ-sitosterol (8.99%) were detected in hemp seed extracts. The octadecenyl ester of hexadecenoic acid (≤31.27%), friedelan-3-one (≤21.49%), dihydrobenzofuran (≤17.07%) and γ-sitosterol (14.03%) were major constituents of the methanolic extracts of hemp roots, collected during various growth stages. The CBD quantity was the highest in hemp flower extracts in pentane (32.73%). The amounts of cannabidiolic acid (CBDA) were up to 24.21% in hemp leaf extracts. The total content of tetrahydrocannabinol (THC) isomers was the highest in hemp flower pentane extracts (≤22.43%). The total phenolic content (TPC) varied from 187.9 to 924.7 (average means, mg/L of gallic acid equivalent (GAE)) in aqueous unshelled hemp seed and flower extracts, respectively. The TPC was determined to be up to 321.0 (mg/L GAE) in root extracts. The antioxidant activity (AA) of hemp extracts and Eos was tested by the spectrophotometric DPPH^● scavenging activity method. The highest AA was recorded for hemp leaf EOs (from 15.034 to 35.036 mmol/L, TROLOX equivalent). In the case of roots, the highest AA (1.556 mmol/L, TROLOX) was found in the extracts of roots collected at the seed maturation stage. The electrochemical (cyclic and square wave voltammetry) assays correlated with the TPC. The hydrogen-peroxide-scavenging activity of extracts was independent of the TPC.

Impact of Elicitation on Plant Antioxidants Production in Taxus Cell Cultures

Elicited cell cultures of Taxus spp. are successfully used as sustainable biotechnological production systems of the anticancer drug paclitaxel, but the effect of the induced metabolomic changes on the synthesis of other bioactive compounds by elicitation has been scarcely studied. In this work, a powerful combinatorial approach based on elicitation and untargeted metabolomics was applied to unravel and characterize the effects of the elicitors 1 µM of coronatine (COR) or 150 µM of salicylic acid (SA) on phenolic biosynthesis in Taxus baccata cell suspensions. Differential effects on cell growth and the phenylpropanoid biosynthetic pathway were observed. Untargeted metabolomics analysis revealed a total of 83 phenolic compounds, mainly flavonoids, phenolic acids, lignans, and stilbenes. The application of multivariate statistics identified the metabolite markers attributed to elicitation over time: up to 34 compounds at 8 days, 41 for 16 days, and 36 after 24 days of culture. The most notable metabolic changes in phenolic metabolism occurred after 8 days of COR and 16 days of SA elicitation. Besides demonstrating the significant and differential impact of elicitation treatments on the metabolic fingerprint of T. baccata cell suspensions, the results indicate that Taxus ssp. biofactories may potentially supply not only taxanes but also valuable phenolic antioxidants, in an efficient optimization of resources.

Non-thermal plasma improved callogenesis performance and elicited the production of cannabinoids by modifying DNA methylome, expression of WRKY1 and ERF1B transcription factors, and expression of genes that contributed to the biosynthesis of cannabinoids

The current decade has witnessed notable advancement towards the utilization of non-thermal (cold) plasma in multidisciplinary fields such as plant sciences. This study intends to validate whether cold plasma contributes to improving callogenesis performance and eliciting the production of cannabinoids in cannabis. The cannabis-derived calli were treated with plasma at different exposure times, including 0, 60, 120, and 180 s. The plasma priming improved the callogenesis performance and callus biomass by an average of 46.6%. The molecular assessment (MSAP method) validated how the plasma priming is epigenetically associated with variation in DNA methylome in the cannabis calli. The cold plasma treatments transcriptionally upregulated the expression of WRKY1 and ERF1B transcription factors by averages of 3.5- and 3.8-fold. The plasma treatment also stimulated the transcription of OLS, OAC, CBGAS, CBDAS, and THCAS genes involved in the biosynthesis of cannabinoids. The HPLC assessment proved the high potency of cold plasma to enhance the synthesis of cannabinoids, including Cannabigerol (CBG), Cannabidiol (CBD), and cannabinol (CBN). The plasma-primed calli contained higher concentrations of proteins (56%), proline (38%), and soluble phenols (40%). The activities of peroxidase and catalase enzymes showed a similar upward trend in response to the plasma. The profound increase in the concentrations of soluble sugars resulted from the plasma treatments. The plasma priming of calli contributed to the significant upregulation in the activity of the phenylalanine ammonia-lyase enzyme. This biological assessment study validates the high potency of plasma priming to elicit the biosynthesis of cannabinoids in cannabis calli.

Current status and future prospects in cannabinoid production through in vitro culture and synthetic biology

For centuries, cannabis has been a rich source of fibrous, pharmaceutical, and recreational ingredients. Phytocannabinoids are the most important and well-known class of cannabis-derived secondary metabolites and display a broad range of health-promoting and psychoactive effects. The unique characteristics of phytocannabinoids (e.g., metabolite likeness, multi-target spectrum, and safety profile) have resulted in the development and approval of several cannabis-derived drugs. While most work has focused on the two main cannabinoids produced in the plant, over 150 unique cannabinoids have been identified. To meet the rapidly growing phytocannabinoid demand, particularly many of the minor cannabinoids found in low amounts in planta, biotechnology offers promising alternatives for biosynthesis through in vitro culture and heterologous systems. In recent years, the engineered production of phytocannabinoids has been obtained through synthetic biology both in vitro (cell suspension culture and hairy root culture) and heterologous systems. However, there are still several bottlenecks (e.g., the complexity of the cannabinoid biosynthetic pathway and optimizing the bioprocess), hampering biosynthesis and scaling up the biotechnological process. The current study reviews recent advances related to in vitro culture-mediated cannabinoid production. Additionally, an integrated overview of promising conventional approaches to cannabinoid production is presented. Progress toward cannabinoid production in heterologous systems and possible avenues for avoiding autotoxicity are also reviewed and highlighted. Machine learning is then introduced as a powerful tool to model, and optimize bioprocesses related to cannabinoid production. Finally, regulation and manipulation of the cannabinoid biosynthetic pathway using CRISPR- mediated metabolic engineering is discussed.

Simulated microgravity contributed to modification of callogenesis performance and secondary metabolite production in CannabisIndica

In vitro plant culture paves the way for meeting the industrial demand of pharmaceutically valuable secondary metabolites. This study intends to monitor how callus cells of Cannabis indica respond to the simulated microgravity (clinorotation; a Man-made technology). Callus initiation resulted from the culture of the leaf explant in a medium supplemented with kinetin (0.5 mgL^-1) and 2, 4-D (2 mgL^-1). Calli were treated with microgravity at three exposure times (0, 3, and 5 days). The microgravity treatments increased callus biomass about 2.5-fold. The clinorotation treatments transcriptionally induced the olivetolic acid cyclase (OAC) and olivetol synthase (OLS) genes about 6.2-fold. The tetrahydrocannabinolic acid synthase (THCAS) and cannabidiolic acid synthase (CBDAS) genes displayed a similar upward trend in response to microgravity. The applied treatments also stimulated the expression of the ethylene-responsive element-binding proteins (ERF1B) and WRKY1 transcription factors by an average of 7.6-fold. Moreover, the simulated microgravity triggered epigenetic modification in the DNA methylation profile. The HPLC-based assessment validated the high efficacy of the clinorotation treatments to increase the concentration of cannabinoids, including Cannabigerol (CBG) and Cannabidiol (CBD). However, the clinorotated calli contained a lower concentration of Tetrahydrocannabinol (THC) than the control group. The microgravity treatments increased concentrations of proline (79%), soluble sugars (61.3%), and proteins (21.4%) in calli. The biochemical assessment revealed that the clinorotation treatments slightly increased H₂O₂ concentration. The upregulation in the activities of peroxidase, catalase, and phenylalanine ammonia-lyase enzymes resulted from the microgravity treatments. Both HPLC and molecular assessments validated the significant efficacy of microgravity to enhance the production of cannabinoids.

Abiotic Stresses Elicitation Potentiates the Productiveness of Cardoon Calli as Bio-Factories for Specialized Metabolites Production

Cultivated cardoon (Cynara cardunculus L. var altilis) is a Mediterranean traditional food crop. It is adapted to xerothermic conditions and also grows in marginal lands, producing a large biomass rich in phenolic bioactive metabolites and has therefore received attention for pharmaceutical, cosmetic and innovative materials applications. Cardoon cell cultures can be used for the biotechnological production of valuable molecules in accordance with the principles of cellular agriculture. In the current study, we developed an elicitation strategy on leaf-derived cardoon calli for boosting the production of bioactive extracts for cosmetics. We tested elicitation conditions that trigger hyper-accumulation of bioactive phenolic metabolites without compromising calli growth through the application of chilling and salt stresses. We monitored changes in growth, polyphenol accumulation, and antioxidant capability, along with transcriptional variations of key chlorogenic acid and flavonoids biosynthetic genes. At moderate stress intensity and duration (14 days at 50–100 mM NaCl) salt exerted the best eliciting effect by stimulating total phenols and antioxidant power without impairing growth. Hydroalcoholic extracts from elicited cardoon calli with optimal growth and bioactive metabolite accumulation were demonstrated to lack cytotoxicity by MTT assay and were able to stimulate pro-collagen and aquaporin production in dermal cells. In conclusion, we propose a “natural” elicitation system that can be easily and safely employed to boost bioactive metabolite accumulation in cardoon cell cultures and also in pilot-scale cell culture production.

Towards a Cardoon (Cynara cardunculus var. altilis)-Based Biorefinery: A Case Study of Improved Cell Cultures via Genetic Modulation of the Phenylpropanoid Pathway

Cultivated cardoon (Cynara cardunculus var. altilis L.) is a promising candidate species for the development of plant cell cultures suitable for large-scale biomass production and recovery of nutraceuticals. We set up a protocol for Agrobacterium tumefaciens-mediated transformation, which can be used for the improvement of cardoon cell cultures in a frame of biorefinery. As high lignin content determines lower saccharification yields for the biomass, we opted for a biotechnological approach, with the purpose of reducing lignin content; we generated transgenic lines overexpressing the Arabidopsis thaliana MYB4 transcription factor, a known repressor of lignin/flavonoid biosynthesis. Here, we report a comprehensive characterization, including metabolic and transcriptomic analyses of AtMYB4 overexpression cardoon lines, in comparison to wild type, underlining favorable traits for their use in biorefinery. Among these, the improved accessibility of the lignocellulosic biomass to degrading enzymes due to depletion of lignin content, the unexpected increased growth rates, and the valuable nutraceutical profiles, in particular for hydroxycinnamic/caffeoylquinic and fatty acids profiles.

Phytochemical characterization and biological properties of two standardized extracts from a non-psychotropic Cannabis sativa L. cannabidiol (CBD)-chemotype

The aim of study was to evaluate and compare the phytochemical profile, the antioxidant and antimicrobial properties of two standardized extracts from non-psychotropic (Δ⁹ -tetrahydrocannabinol ≤0.2%) Cannabis sativa L. var. fibrante rich in cannabidiol (CBD). The two extracts, namely Cannabis Fibrante Hexane Extract 1 (CFHE1) and Cannabis Fibrante Hexane Extract 2 (CFHE2), were obtained by extraction with acidified hexane from dried flowering tops as such and after hydrodistillation of the essential oil, respectively. Gas chromatographic analysis showed that cannabinoids remained the predominant class of compounds in both extracts (82.56% and 86.38%, respectively), whereas a marked depletion of the terpenes occurred. Moreover, liquid chromatographic analysis highlighted a high titer of cannabidiol acid (CBDA) and CBD in CFHE1 and CFHE2, respectively. Both extracts showed a strong and concentration-dependent antioxidant activity and a potent antimicrobial activity against both Staphylococcus aureus ATCC 6538 (MIC and MBC of 4.88 μg/ml for CFHE1, and 4.88 and 19.53 μg/ml, respectively, for CFHE2) and methicillin resistant clinical strains (MIC values between 1.22 and 9.77 μg/ml and MBC values between 4.88 and 78.13 μg/ml). Considering this, the obtained results suggest that standardized extracts of C. sativa var. fibrante could find promising applications as novel antimicrobial agents.

Advances and Perspectives in Tissue Culture and Genetic Engineering of Cannabis

For a long time, Cannabis sativa has been used for therapeutic and industrial purposes. Due to its increasing demand in medicine, recreation, and industry, there is a dire need to apply new biotechnological tools to introduce new genotypes with desirable traits and enhanced secondary metabolite production. Micropropagation, conservation, cell suspension culture, hairy root culture, polyploidy manipulation, and Agrobacterium-mediated gene transformation have been studied and used in cannabis. However, some obstacles such as the low rate of transgenic plant regeneration and low efficiency of secondary metabolite production in hairy root culture and cell suspension culture have restricted the application of these approaches in cannabis. In the current review, in vitro culture and genetic engineering methods in cannabis along with other promising techniques such as morphogenic genes, new computational approaches, clustered regularly interspaced short palindromic repeats (CRISPR), CRISPR/Cas9-equipped Agrobacterium-mediated genome editing, and hairy root culture, that can help improve gene transformation and plant regeneration, as well as enhance secondary metabolite production, have been highlighted and discussed.

Anticancer property of Hemp Bioactive Peptides in Hep3B liver cancer cells through Akt/GSK3β/β-catenin signaling pathway

Foodborne protein hydrolysates exhibit biological activity that may be therapeutic in a number of human disease settings. Hemp peptides (HP) generated by controlled hydrolysis of hemp proteins have a number of health benefits and are of pharmaceutical value. In the present study, we produce small molecular weight HP from hemp seed and investigate its anticancer properties in Hep3B human liver cancer cells. We demonstrate that HP treatment increased apoptosis, reduced cell viability, and reduced cell migration in Hep3B human liver cancer cells without affecting the normal liver cell line L02. We correlate these phenotypes with increased cellular ROS levels, upregulation of cleaved caspase 3 and Bad, and downregulation of antiapoptotic Bcl-2. HP treatment led to increased Akt and GSK-3β phosphorylation, with subsequent downregulation of β-catenin, suggesting β-catenin signaling modulation as a critical mechanism by which HP exhibits anticancer properties. Our findings suggest HP are of potential therapeutic interest for liver cancer treatment.

Effects of Abiotic Elicitors on Expression and Accumulation of Three Candidate Benzophenanthridine Alkaloids in Cultured Greater Celandine Cells

Efforts to develop the necessary biotechnologies in Greater Celandine (Chelidonium majus L.), a leading plant resource for the development of plant-derived medicines, have been hampered by the lack of knowledge about transcriptome and metabolome regulations of its medicinal components. Therefore, this study aimed to examine the effect of abiotic elicitors, methyl jasmonate (MJ) and salicylic acid (SA), at different time courses (12, 24, 48, and 72 h), on expression and metabolome of key benzophenanthridine alkaloids (BPAs) in an optimized in vitro culture. Gene expression analysis indicated the upregulation of CFS (cheilanthifoline synthase) to 2.62, 4.85, and 7.28 times higher than the control at 12, 24, and 48 h respectively, under MJ elicitation. Besides, MJ upregulated the expression of TNMT (tetrahydroprotoberberine N-methyltransferase) to 2.79, 4.75, and 7.21 times at 12, 24, and 48 h respectively, compared to the control. Investigation of BPAs revealed a significant enhancement in the chelidonine content (9.86 µg/mg) after 72 h of MJ elicitation. Additionally, sanguinarine content increased to its highest level (3.42 µg/mg) after 24 h of MJ elicitation; however, no significant enhancement was detected in its content in shorter elicitation time courses. Generally, higher gene expression and BPAs’ level was observed through longer elicitation courses (48 and 72 h). Our findings take part in improving the understanding of transcription and metabolic regulation of BPAs in cultured Greater Celandine cells.

Metabolic Engineering Strategies of Industrial Hemp (Cannabis sativa L.): A Brief Review of the Advances and Challenges

Industrial hemp (Cannabis sativa L.) is a diploid (2n = 20), dioecious plant that is grown for fiber, seed, and oil. Recently, there has been a renewed interest in this crop because of its panoply of cannabinoids, terpenes, and other phenolic compounds. Specifically, hemp contains terpenophenolic compounds such as cannabidiol (CBD) and cannabigerol (CBG), which act on cannabinoid receptors and positively regulate various human metabolic, immunological, and physiological functions. CBD and CBG have an effect on the cytokine metabolism, which has led to the examination of cannabinoids on the treatment of viral diseases, including COVID-19. Based on genomic, transcriptomic, and metabolomic studies, several synthetic pathways of hemp secondary metabolite production have been elucidated. Nevertheless, there are few reports on hemp metabolic engineering despite obvious impact on scientific and industrial sectors. In this article, recent status and current perspectives on hemp metabolic engineering are reviewed. Three distinct approaches to expedite phytochemical yield are discussed. Special emphasis has been placed on transgenic and transient gene delivery systems, which are critical for successful metabolic engineering of hemp. The advent of new tools in synthetic biology, particularly the CRISPR/Cas systems, enables environment-friendly metabolic engineering to increase the production of desirable hemp phytochemicals while eliminating the psychoactive compounds, such as tetrahydrocannabinol (THC).

Comprehending and improving cannabis specialized metabolism in the systems biology era

Cannabis sativa is a source of food, fiber and specialized metabolites such as cannabinoids, with psychoactive and pharmacological effects. Due to its expanding and increasingly-accepted use in medicine, cannabis cultivation is acquiring more importance and less social stigma. Humans initiated different domestication episodes whose later spread gave rise to a plethora of landrace cultivars. At present, breeders cross germplasms from different gene pools depending on their specific use. The fiber (hemp) and drug (marijuana) types of C. sativa differ in their cannabinoid chemical composition phenotype (chemotype) and also in the accumulation of terpenoid compounds that constitute a strain's particular flavor and scent. Cannabinoids are isoprenylated polyketides among which cannabidiolic acid (CBDA) and (-)-trans-Δ⁹-tetrahydrocannabinol acid (THCA) have been well-documented for their many effects on humans. Here, we review the most studied specialized metabolic pathways in C. sativa, showing how terpenes and cannabinoids share both part of the isoprenoid pathway and the same biosynthetic compartmentalization (i.e. glandular trichomes of leaves and flowers). We enlist the several studies that have deciphered these pathways in this species including physical and genetic maps, QTL analyses and localization and enzymatic studies of cannabinoid and terpene synthases. In addition, new comparative modeling of cannabinoid synthases and phylogenetic trees are presented. We describe the genome sequencing initiatives of several accessions with the concomitant generation of next-generation genome maps and transcriptomic data. Very recently, proteomic characterizations and systems biology approaches such as those applying network theory or the integration of multi-omics data have increased the knowledge on gene function, enzyme diversity and metabolite content in C. sativa. In this revision we drift through the history, present and future of cannabis research and on how second- and third-generation sequencing technologies are bringing light to the field of cannabis specialized metabolism. We also discuss different biotechnological approaches for producing cannabinoids in engineered microorganisms.

Elicitation-Based Method for Increasing the Production of Antioxidant and Bactericidal Phenolic Compounds in Dionaea muscipula J. Ellis Tissue

The carnivorous plant Dionaea muscipula J. Ellis (Venus flytrap) is a widely known medical herb, capable of producing various phenolic compounds known for their strong antioxidant and antibacterial properties. In the pharmaceutical industry, Venus flytrap is grown in tissue cultures, as the natural population of D. muscipula is very limited. Here, we describe an improved method to increase the quantity and quality of phenolic compounds produced in D. muscipula. This is achieved by combining biotic elicitation (using Cronobacter sakazakii bacteria lysate) of D. muscipula cultured with rotary shaking (hydromechanical stress), which we describe here for the first time. The antibacterial activity and the antioxidant properties of the obtained compounds were studied on two antibiotic-resistant human pathogenic bacteria. The proposed plant culture conditions resulted in an increase in fresh weight, as well as a higher total phenolic content, in comparison to traditional tissue cultures on agar-solidified medium. With the use of high-performance liquid chromatography, we demonstrated that the described elicitation strategy leads to an increased synthesis of myricetin, caffeic acid, ellagic acid and plumbagin in D. muscipula tissue. We also found that a higher level of antioxidant activity, exhibited by the plant extract, corresponded with its higher phenylpropanoid content. The bactericidal activity of the extract against Staphylococcus aureus was dependent on the duration of plant culture under described elicitation conditions, whereas neither elicitation condition (duration or elicitor concentration) seemed relevant for the bactericidal activity of the extract towards Escherichia coli. This suggest that Gram-negative bacteria are less sensitive to compounds derived from Venus flytrap tissue.