Ultrasound-Assisted Extraction of Cannabinoids from Cannabis Sativa L. Optimized by Response Surface Methodology

Ellagitannin Content in Extracts of the Chestnut Wood Aesculus

The chestnut tree (Castanea sativa Mill.) is a widespread plant in Europe, rich in high-value compounds, which can be divided mainly into monomeric polyphenols and tannins. These compounds exhibit various biological activities, such as antioxidant, as well as anticarcinogenic and antimicrobial properties. Chestnut wood (CW) extracts were prepared using different extraction techniques, process conditions, solvents, and their mixtures. This work aimed to test various extraction techniques and determine the optimal solvent for isolating enriched fractions of vescalagin, castalagin, vescalin, and castalin from CW residues. Supercritical CO2 extraction with a more polar cosolvent was applied at different pressures, which influenced solvent density. According to the results, the proportions of the components strongly depended on the solvent system used for the extraction. In addition, HPLC-DAD was used for semiqualitative purposes to detect vescalagin, castalagin, vescalin, and castalin. The developed valorization protocol allows efficient fractionation and recovery of the polyphenolic components of CW through a sustainable approach that also evaluates pre-industrial scaling-up.

Arbuscular Mycorrhizal Fungi-Mediated Modulation of Physiological, Biochemical, and Secondary Metabolite Responses in Hemp (Cannabis sativa L.) under Salt and Drought Stress

The increasing impact of global climate change has resulted in adversity stresses, like salt and drought, gradually becoming the main factors that limit crop growth. Hemp, which contains numerous medicinal active components and multiple bioactive functions, is widely used in the agricultural, industrial, and medical fields, hence promoting the rapid development of related industries. Arbuscular mycorrhizal fungi (AMF) can establish a symbiotic relationship with 80% of vascular plants. This symbiosis promotes host plant growth, regulates plant physiology and biochemistry, facilitates secondary metabolite synthesis, and enhances resistance to abiotic stresses. However, the effects of salt stress, drought stress, and AMF interaction in hemp are not well understood. In this study, to investigate this, we performed a study where we cultured hemp that was either inoculated or uninoculated with Funneliformis mosseae and determined changes in effective colonization rate, growth, soluble substances, photosynthesis, fluorescence, ions, and secondary metabolites by cultivating hemp under different concentrations of NaCl (0 mM, 100 mM, and 200 mM) and different soil moisture content (45%, 25%, and 15%). The results showed that salt, drought stress, or salt-drought interaction stress all inhibited colonization rate after stress, plant growth, mainly due to ion toxicity and oxidative damage. Inoculation with F. mosseae effectively alleviated plant growth inhibition under 100 mM NaCl salt stress, drought stress, and salt-drought interaction stress conditions. It also improved osmoregulation, photosynthetic properties, fluorescence properties, and ion homeostasis, and promoted the accumulation of secondary metabolites. However, under 200 mM NaCl salt stress conditions, inoculation with F. mosseae negatively affected plant physiology, biochemistry, and secondary metabolite synthesis, although it did alleviate growth inhibition. The results demonstrate that there are different effects of salt-drought interaction stress versus single stress (salt or drought stress) on plant growth physiology. In addition, we provide new insights about the positive effects of AMF on host plants under such stress conditions and the effects of AMF on plants under high salt stress.

Cannabinoids in Medicine: A Multifaceted Exploration of Types, Therapeutic Applications, and Emerging Opportunities in Neurodegenerative Diseases and Cancer Therapy

In this review article, we embark on a thorough exploration of cannabinoids, compounds that have garnered considerable attention for their potential therapeutic applications. Initially, this article delves into the fundamental background of cannabinoids, emphasizing the role of endogenous cannabinoids in the human body and outlining their significance in studying neurodegenerative diseases and cancer. Building on this foundation, this article categorizes cannabinoids into three main types: phytocannabinoids (plant-derived cannabinoids), endocannabinoids (naturally occurring in the body), and synthetic cannabinoids (laboratory-produced cannabinoids). The intricate mechanisms through which these compounds interact with cannabinoid receptors and signaling pathways are elucidated. A comprehensive overview of cannabinoid pharmacology follows, highlighting their absorption, distribution, metabolism, and excretion, as well as their pharmacokinetic and pharmacodynamic properties. Special emphasis is placed on the role of cannabinoids in neurodegenerative diseases, showcasing their potential benefits in conditions such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. The potential antitumor properties of cannabinoids are also investigated, exploring their potential therapeutic applications in cancer treatment and the mechanisms underlying their anticancer effects. Clinical aspects are thoroughly discussed, from the viability of cannabinoids as therapeutic agents to current clinical trials, safety considerations, and the adverse effects observed. This review culminates in a discussion of promising future research avenues and the broader implications for cannabinoid-based therapies, concluding with a reflection on the immense potential of cannabinoids in modern medicine.

Trends in Illicit Cannabis Potency based on the Analysis of Law Enforcement Seizures in the Southern Area of Rome

Cannabis remains the most illicitly produced and consumed substance worldwide, and the average trans-Δ9-tetrahydrocannabinol (THC) content in cannabis products (marijuana, hashish) has increased over time. This paper presents data about THC concentration in cannabis resin samples seized by law enforcement from 2015 to 2022 in the southern area of Rome (Italy). From 2015 to 2022, more than 1000 hashish samples were analyzed; the average THC content was 18.0% and dramatically increased from 13.7% (2015) to 27.1% (2022). The potency of THC in some samples characterized by unusual shape and color was higher than 24% and, in a few cases, higher than 40%. The age group most involved in seizures of cannabis resin concerned males aged between 15 and 36 years old. The spread of this phenomenon increases the risk of adverse health outcomes. Many observational studies compare the increased cannabis potency with the onset of psychosis, depression, anxiety and cannabis use disorders (CUDs), mainly in young adults. THC-potency monitoring provides data that can be helpful to create a network of communication and interaction between universities, and legislative and public health institutions to support education, awareness and surveillance related to cannabis abuse.

Study of Cannabis Oils Obtained from Three Varieties of C. sativa and by Two Different Extraction Methods: Phytochemical Characterization and Biological Activities

Currently, much effort is being placed into obtaining extracts and/or essential oils from Cannabis sativa L. for specific therapeutic purposes or pharmacological compositions. These potential applications depend mainly on the phytochemical composition of the oils, which in turn are determined by the type of C. sativa and the extraction method used to obtain the oils. In this work, we have evaluated the contents of secondary metabolites, delta-9-tetrahydrocannabinol (THC), and cannabidiol (CBD), in addition to the total phenolic, flavonoids, and anthraquinone content in oils obtained using solid-liquid extraction (SLE) and supercritical fluid extraction (SCF). Different varieties of C. sativa were chosen by using the ratio of THC to CBD concentrations. Additionally, antioxidant, antifungal and anticancer activities on different cancer cell lines were evaluated in vitro. The results indicate that oils extracted by SLE, with high contents of CBD, flavonoids, and phenolic compounds, exhibit a high antioxidant capacity and induce a high decrease in the cell viability of the tested breast cancer cell line (MCF-7). The observed biological activities are attributed to the entourage effect, in which CBD, phenols and flavonoids play a key role. Therefore, it is concluded that the right selection of C. sativa variety and the solvent for SLE extraction method could be used to obtain the optimal oil composition to develop a natural anticancer agent.

Response Surface Optimization of Extraction Conditions for the Active Components with High Acetylcholinesterase Inhibitory Activity and Identification of Key Metabolites from Acer truncatum Seed Oil Residue

The State Council of China has called for the comprehensive development and utilization of Acer truncatum resources. However, research on one of its by-products, namely seed oil residue (ASR), from seed oil extraction is seriously insufficient, resulting in a waste of these precious resources. We aimed to optimize the conditions of ultrasound-assisted extraction (UAE) using a response surface methodology to obtain high acetylcholinesterase (AChE) inhibitory components from ASR and to tentatively identify the active metabolites in ASR using non-targeted metabolomics. Based on the results of the independent variables test, the interaction effects of three key extracting variables, including methanol concentration, ultrasonic time, and material-to-liquid ratio, were further investigated using the Box-Behnken design (BBD) to obtain prior active components with high AChE inhibitory activity. UPLC-QTOF-MS combined with a multivariate method was used to analyze the metabolites in ASR and investigate the causes of activity differences. Based on the current study, the optimal conditions for UAE were as follows: methanol concentration of 85.06%, ultrasonic time of 39.1 min, and material-to-liquid ratio of 1.06:10 (g/mL). Under these optimal conditions, the obtained extracts show strong inhibitions against AChE with half maximal inhibitory concentration (IC₅₀) values ranging from 0.375 to 0.459 µg/mL according to an Ellman's method evaluation. Furthermore, 55 metabolites were identified from the ASR extracted using methanol in different concentrations, and 9 biomarkers were subsequently identified as potential compounds responsible for the observed AChE inhibition. The active extracts have potential to be used for the development of functional foods with positive effects on Alzheimer's disease owing to their high AChE inhibition activity. Altogether, this study provides insights into promoting the comprehensive utilization of A. truncatum resources.

Cannabis Extraction Technologies: Impact of Research and Value Addition in Latin America

The Cannabis genus of plants has been widely used in different cultures for various purposes. It is separated into three main species: sativa, indica, and ruderalis. In ancient practices, the plant was used as a multipurpose crop and valued for its fiber, food, and medicinal uses. Since methodologies for the extraction, processing, and identification of components have become available, medical, and food applications have been increasing, allowing potential development in the pharmaceutical and healthy functional food industries. Although the growing legalization and adoption of cannabis for the treatment of diseases are key factors pushing the growth of its market, the biggest challenge is to obtain higher-quality products in a time- and cost-effective fashion, making the process of extraction and separation an essential step. Latin American countries exhibit great knowledge of extraction technologies; nevertheless, it is still necessary to verify whether production costs are economically profitable. In addition, there has been an increase in commercial cannabis products that may or may not be allowed, with or without quality fact sheets, which can pose health risks. Hence, legalization is mandatory and urgent for the rest of Latin American countries. In this article, the phytochemical compounds (cannabinoids, terpenes, and phenolic compounds), the current status of legalization, extraction techniques, and research advances in cannabis in Latin America are reviewed.

Extraction techniques for bioactive compounds of cannabis

Historically, cannabis has always constituted a component of the civilized world; archaeological discoveries indicate that it is one of the oldest crops, while, up until the 19th century, cannabis fibers were extensively used in a variety of applications, and its seeds comprised a part of human and livestock nutrition. Additional evidence supports its exploitation for medicinal purposes in the ancient world. The cultivation of cannabis gradually declined as hemp fibers gave way to synthetic fibers, while the intoxicating ability of THC eventually overshadowed the extensive potential of cannabis. Nevertheless, the proven value of certain non-intoxicating cannabinoids, such as CBD and CBN, has recently given rise to an entire market which promotes cannabis-based products. An increase in the research for recovery and exploitation of beneficial cannabinoids has also been observed, with more than 10 000 peer-reviewed research articles published annually. In the present review, a brief overview of the history of cannabis is given. A look into the classification approaches of cannabis plants/species as well as the associated nomenclature is provided, followed by a description of their chemical characteristics and their medically valuable components. The application areas could not be absent from the present review. Still, the main focus of the review is the discussion of work conducted in the field of extraction of valuable bioactive compounds from cannabis. We conclude with a summary of the current status and outlook on the topics that future research should address.

Response surface methodology as a tool to optimize the extraction of bioactive compounds from plant sources

Response surface methodology (RSM) is a widely used mathematical and statistical technique for modeling and optimizing the process for the extraction of bioactive compounds. This review explains the optimization approach through the use of experimental design and empirical models for response prediction and the utilization of the desirability function for multiple response optimization. This paper also reviews recent studies on the application of RSM to optimize bioactive compound extraction processes such as conventional solvent extraction, microwave-assisted extraction, supercritical fluid extraction, and ultrasound-assisted extraction. Finally, the challenges associated with the use of RSM and the efforts made to improve RSM in the extraction process are also highlighted. Overall, this review informs many aspects of RSM that are occasionally ignored or insufficiently discussed with regard to the optimization of bioactive compound extraction processes, and it summarizes significant applications where RSM proved suitable. © 2022 Society of Chemical Industry.

Optimization of Ultrasound- and Microwave-Assisted Extraction for the Determination of Phenolic Compounds in Peach Byproducts Using Experimental Design and Liquid Chromatography-Tandem Mass Spectrometry

The conversion of plant byproducts, which are phenolic-rich substrates, to valuable co-products by implementing non-conventional extraction techniques is the need of the hour. In the current study, ultrasound- (UAE) and microwave-assisted extraction (MAE) were applied for the recovery of polyphenols from peach byproducts. Two-level screening and Box-Behnken design were adopted to optimize extraction efficiency in terms of total phenolic content (TPC). Methanol:water 4:1% v/v was the extraction solvent. The optimal conditions of UAE were 15 min, 8 s ON-5 s OFF, and 35 mL g^-1, while MAE was maximized at 20 min, 58 °C, and 16 mL g^-1. Regarding the extracts' TPC and antioxidant activity, MAE emerged as the method of choice, whilst their antiradical activity was similar in both techniques. Furthermore, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine chlorogenic acid and naringenin in byproducts' extracts. 4-Chloro-4'-hydroxybenzophenone is proposed as a new internal standard in LC-MS/MS analysis in foods and byproducts. Chlorogenic acid was extracted in higher yields when UAE was used, while MAE favored the extraction of the flavonoid compound, naringenin. To conclude, non-conventional extraction could be considered as an efficient and fast alternative for the recovery of bioactive compounds from plant matrices.

Microwave- and Ultrasound-Assisted Extraction of Cannabinoids and Terpenes from Cannabis Using Response Surface Methodology

Limited studies have explored different extraction techniques that improve cannabis extraction with scale-up potential. Ultrasound-assisted and microwave-assisted extraction were evaluated to maximize the yield and concentration of cannabinoids and terpenes. A central composite rotatable design was used to optimize independent factors (sample-to-solvent ratio, extraction time, extraction temperature, and duty cycle). The optimal conditions for ultrasound- and microwave-assisted extraction were the sample-to-solvent ratios of 1:15 and 1:14.4, respectively, for 30 min at 60 °C. Ultrasound-assisted extraction yielded 14.4% and 14.2% more oil and terpenes, respectively, compared with microwave-assisted extracts. Ultrasound-assisted extraction increased cannabinoid concentration from 13.2−39.2%. Considering reference ground samples, tetrahydrocannabinolic acid increased from 17.9 (g 100 g dry matter−1) to 28.5 and 20 with extraction efficiencies of 159.2% and 111.4% for ultrasound-assisted and microwave-assisted extraction, respectively. Principal component analyses indicate that the first two principal components accounted for 96.6% of the total variance (PC1 = 93.2% and PC2 = 3.4%) for ultrasound-assisted extraction and 92.4% of the total variance (PC1 = 85.4% and PC2 = 7%) for microwave-assisted extraction. Sample-to-solvent ratios significantly (p < 0.05) influenced the secondary metabolite profiles and yields for ultrasound-assisted extracts, but not microwave-assisted extracts.

Ultrasound-Assisted Extraction of Cannabinoids from Cannabis Sativa for Medicinal Purpose

Over the past 20 years, the interest in Cannabis oily extracts for medicinal use compounded in pharmacy has consistently grown, along with the need to have preparations of adequate quality. Hot maceration (M) is the most frequently used method to compound oily solutions. In this work, we systematically studied the possibility of using an ultrasonic homogenizer and a sonotrode (US) as an alternative extraction method. Oily solutions were prepared using two available varieties of Cannabis for medicinal use, called FM2 and Bedrocan. All preparations resulted with an equivalent content in CBD and THC, with the advantage of a faster process using US. In particular, 10 min sonication at the amplitude optimized for the sonotrode used (2 or 7 mm) provides not statistically different total Δ9-tetrahydrocannabinol (M-FM2: 0.26 ± 0.02 % w/w; US-FM2: 0.19 ± 0.004 % w/w; M-Bedrocan: 1.83 ± 0.17 % w/w; US-Bedrocan: 1.98 ± 0.01 % w/w) and total cannabidiol (M-FM2: 0.59 ± 0.04 % w/w; US-FM2: 0.58 ± 0.01 % w/w) amounts extracted in refined olive oil. It can therefore be confirmed that sonotrode is an efficient and fast extraction technique and its use is without negative consequence on the solvent properties. Despite DSC evidencing that both maceration and sonication modify the T_onset and enthalpy of the event at about -10 °C, the qualitative characteristics of the oil remained constant for the two treatments and similar to the starting material.

Ultrasound-assisted extraction, optimization, isolation, and antioxidant activity analysis of flavonoids from Astragalus membranaceus stems and leaves

Astragalus membranaceus is a medicinal and edible species in China, with a variety of biological activities. This study evaluated the reuse potential of A. membranaceus waste as a source of food antioxidants. Antioxidant and antifungal activities of flavonoids, polysaccharides, and saponins from A. membranaceus stems and leaves were evaluated. Results showed that inhibition rate of flavonoids on six tested fungi reaches 100 % at a concentration of 5 mg/mL, and the antioxidant test demonstrated satisfactory antioxidant activity. On this basis, an extremely economical ultrasonic-assisted extraction of flavonoids from A. membranaceus stems and leaves was developed and optimized via response surface methodology (RSM). Optimized conditions included an extraction time of 35 min, ethanol concentration of 75 %, liquid-solid ratio of 40 mL/g, and extraction temperature of 58 °C, in which the extraction yield of flavonoids was 22.0270 ± 2.5739 mg/g. The total flavonoids were separated and purified using activity-guided isolation technology, and frac. ccd with strong antioxidant activity were analyzed via HPLC-MS/MS. Results showed that main components are isoquercitrin and astragalin. This study can provide a potential innovative application for the development of natural food antioxidants from A. membranaceus waste.

Postharvest Operations of Cannabis and Their Effect on Cannabinoid Content: A Review

In recent years, cannabis (Cannabis sativa L.) has been legalized by many countries for production, processing, and use considering its tremendous medical and industrial applications. Cannabis contains more than a hundred biomolecules (cannabinoids) which have the potentiality to cure different chronic diseases. After harvesting, cannabis undergoes different postharvest operations including drying, curing, storage, etc. Presently, the cannabis industry relies on different traditional postharvest operations, which may result in an inconsistent quality of products. In this review, we aimed to describe the biosynthesis process of major cannabinoids, postharvest operations used by the cannabis industry, and the consequences of postharvest operations on the cannabinoid profile. As drying is the most important post-harvest operation of cannabis, the attributes associated with drying (water activity, equilibrium moisture content, sorption isotherms, etc.) and the significance of novel pre-treatments (microwave heating, cold plasma, ultrasound, pulse electric, irradiation, etc.) for improvement of the process are thoroughly discussed. Additionally, other operations, such as trimming, curing, packaging and storage, are discussed, and the effect of the different postharvest operations on the cannabinoid yield is summarized. A critical investigation of the factors involved in each postharvest operation is indeed key for obtaining quality products and for the sustainable development of the cannabis industry.

Rapid In Situ Detection of THC and CBD in Cannabis sativa L. by 1064 nm Raman Spectroscopy

The need to find a rapid and worthwhile technique for the in situ detection of the content of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in Cannabis sativa L. is an ever-increasing problem in the forensic field. Among all the techniques for the detection of cannabinoids, Raman spectroscopy can be identified as the most cost-effective, fast, noninvasive, and nondestructive. In this study, 42 different samples were analyzed using Raman spectroscopy with 1064 nm excitation wavelength. The use of an IR wavelength laser showed the possibility to clearly identify THC and CBD in fresh samples, without any further processing, knocking out the contribution of the fluorescence generated by visible and near-IR sources. The results allow assigning all the Raman features in THC- and CBD-rich natural samples. The multivariate analysis underlines the high reproducibility of the spectra and the possibility to distinguish immediately the Raman spectra of the two cannabinoid species. Furthermore, the ratio between the Raman bands at 1295/1440 and 1623/1663 cm^–1 is identified as an immediate test parameter to evaluate the THC content in the samples.

Tannin-based coagulants: Current development and prospects on synthesis and uses

Population growth, industrialization, urbanization, and agriculture lead to a decrease in the availability of clean water. Coagulation/flocculation is one of the most common operations in water, urban wastewater, and industrial effluents treatment systems. Usually, this process is achieved using conventional coagulants that have their performance affected by pH, are poorly biodegradable, produce a huge volume of sludge, and are associated with degenerative diseases. As a substitute for these chemicals, natural coagulants have been highly researched for the last ten/fifteen years, especially the tannin-based (TB) ones. This review paper highlights the advantages of using these greener products to treat different types of water, wastewater, and effluents, especially from dairy, cosmetics, laundries, textile, and other industries. TB coagulants can successfully remove turbidity, color, suspended solids, soluble organic (chemical/biochemical oxygen demand) and inorganic matter (total phosphate, and heavy metals), and microorganisms. TB coagulants are compatible with other treatment technologies and can be used as coagulant-aid to reduce the consumption of chemicals. TB coagulants can reduce operating costs of water treatment due to less alkalinity consumption, as pH adjustment is sometimes unnecessary, and the production of a smaller volume of biodegradable sludge. TB coagulants can be synthesized by valorizing wastes/by-products, from the bark of some specific trees and skins/pomace of different fruits and vegetables. The strengths, weaknesses, opportunities, and threats (SWOT) on TB coagulants are discussed. The progress of TB coagulants is promising, but some threats should be overcome, especially on tannin extraction and cationization. The market competition with conventional coagulants, the feasibility of application in real waters, and the reluctance of the industries to adapt to new technologies are other weaknesses to be surpassed.

Vanillic Acid as a Promising Xanthine Oxidase Inhibitor: Extraction from Amomum villosum Lour and Biocompatibility Improvement via Extract Nanoemulsion

Gout is an oxidative stress-related disease. Food-derived vanillic acid, a promising xanthine oxidase inhibitor, could potentially be used as a safe, supportive, and therapeutic product for gout. The extraction of vanillic acid from a classic Chinese herbal plant Amomum villosum with ethanol was investigated in the study. The optimum conditions were determined as extraction time of 74 min, extraction temperature of 48.36 °C, and a solid-to-liquid ratio of 1:35 g·mL⁻¹ using the Box–Behnken design (BBD) of response surface methodology (RSM). The experimental extraction yield of 9.276 mg·g⁻¹ matched with the theoretical value of 9.272 ± 0.011 mg·g⁻¹ predicted by the model. The vanillic acid in Amomum villosum was determined to be 0.5450 mg·g⁻¹ by high-performance liquid chromatography–diode array detection (HPLC–DAD) under the optimum extraction conditions and exhibited xanthine oxidase (XO) inhibitory activity, with the half-maximal inhibitory concentration (IC50) of 1.762 mg·mL⁻¹. The nanoemulsion of Amomum villosum extract consists of 49.97% distilled water, 35.09% S_mix (mixture of tween 80 and 95% ethanol with 2:1 ratio), and 14.94% n-octanol, with a particle size of 110.3 ± 1.9 nm. The nanoemulsion of Amomum villosum extract exhibited markable XO inhibitory activity, with an inhibition rate of 58.71%. The result demonstrated the potential benefit of Amomum villosum as an important dietary source of xanthine oxidase inhibitors for gout.

Cannabis: Chemistry, extraction and therapeutic applications

Cannabis, a genus of perennial indigenous plants is well known for its recreational and medicinal activities. Cannabis and its derivatives have potential therapeutic activities to treat epilepsy, anxiety, depression, tumors, cancer, Alzheimer's disease, Parkinson's disease, to name a few. This article reviews some recent literature on the bioactive constituents of Cannabis, commonly known as phytocannabinoids, their interactions with the different cannabinoids and non-cannabinoid receptors as well as the significances of these interactions in treating various diseases and syndromes. The biochemistry of some notable cannabinoids such as tetrahydrocannabinol, cannabidiol, cannabinol, cannabigerol, cannabichromene and their carboxylic acid derivatives is explained in the context of therapeutic activities. The medicinal features of Cannabis-derived terpenes are elucidated for treating several neuro and non-neuro disorders. Different extraction techniques to recover cannabinoids are systematically discussed. Besides the medicinal activities, the traditional and recreational utilities of Cannabis and its derivatives are presented. A brief note on the legalization of Cannabis-derived products is provided. This review provides comprehensive knowledge about the medicinal properties, recreational usage, extraction techniques, legalization and some prospects of cannabinoids and terpenes extracted from Cannabis.

Optimizing the Desorption Technology of Total Flavonoids of Ginkgo Biloba from Separating Materials of Activated Carbon

Activated carbon adsorption is one of the processes used to produce ginkgolides from the extract of Ginkgo biloba (EGB) in most enterprises. However, the problem is that the ginkgolides can be eluted by ethanol after the Ginkgo biloba extracts are adsorbed by activated carbon, while total ginkgo flavonoids (TGFs) would form dead adsorption, leading to the ineffective utilization of TGFs. In this paper, the maximum adsorption capacity of TGFs by activated carbon was 226.7 mg/g activated carbon at pH 5, and the adsorption of TGFs was easier and more favorable to monolayer adsorption. On this basis, the technical process of desorption of TGFs from activated carbon preparation technology was optimized by using the response surface optimization technique. Under the optimum process (the elution volume was 116.75 mL, the ethanol concentration in the eluent was 73.4%, the elution temperature was 31.5 °C, and the ammonia concentration was 5.7%), the desorption rate of TGFs was 74.56%. Scanning electron microscopy morphological analysis showed that the used activated carbon had a wide pore size distribution, with the micropore pore size mainly concentrated around 0.64 and 1.00 nm and the mesopore pore size mainly concentrated between 2.89 and 39.5 nm. In addition, the molecular weight of ginkgo flavonoids is mainly distributed between 500 and 1000 Da, which can be transported to the micropores through the mesopore channels. On the other hand, there is a force between the flavonoids and the acidic oxygen-containing functional groups on the pore surface, which is the main reason for the formation of dead adsorption. The obtained results contribute to further improving the process of adsorbing and desorbing TGFs from EGB and lay a foundation for the development of more suitable activated carbon.

Combined ionic liquid and supercritical carbon dioxide based dynamic extraction of six cannabinoids from Cannabis sativa L

The potential of supercritical CO2 and ionic liquids (ILs) as alternatives to traditional extraction of natural compounds from plant material is of increasing importance. Both techniques offer several advantages over conventional extraction methods. These two alternatives have been separately employed on numerous ocassions, however, until now, they have never been combined for the extraction of secondary metabolites from natural sources, despite properties that complement each other perfectly. Herein, we present the first application of an IL-based dynamic supercritical CO2 extraction of six cannabinoids (CBD, CBDA, Δ9-THC, THCA, CBG and CBGA) from industrial hemp (Cannabis sativa L.). Various process parameters were optimized, i.e., IL-based pre-treatment time and pre-treatment temperature, as well as pressure and temperature during supercritical fluid extraction. In addition, the impact of different ILs on cannabinoid extraction yield was evaluated, namely, 1-ethyl-3-methylimidazolium acetate, choline acetate and 1-ethyl-3-methylimidazolium dimethylphosphate. This novel technique exhibits a synergistic effect that allows the solvent-free acquisition of cannabinoids from industrial hemp, avoiding further processing steps and the additional use of resources. The newly developed IL-based supercritical CO2 extraction results in high yields of the investigated cannabinoids, thus, demonstrating an effective and reliable alternative to established extraction methods. Ultimately, the ILs can be recycled to reduce costs and to improve the sustainability of the developed extraction process.

Effects of Ethanol on the Supercritical Carbon Dioxide Extraction of Cannabinoids from Near Equimolar (THC and CBD Balanced) Cannabis Flower

In this study, supercritical carbon dioxide (scCO2) extractions of cannabinoids were conducted at four different densities (231, 590, 818, and 911 kg/m3) using ethanol (5% w/v) as a co-solvent. The chemical profiles of these cannabinoids were analysed via reverse-phase high-performance liquid chromatography (RP-HPLC). It was determined that scCO2, at low density (231 kg/m3), produced an extract yield of 6.1% w/v. At high scCO2 density (~818 kg/m3), the yield was 16.1% w/v. More specifically, the amounts of tetrahydrocannabinol (THC) and cannabidiol (CBD) in the scCO2 extract at 818 kg/m3 were 10.8 and 15.6% w/v, respectively. It was also found that the use of 5% w/v ethanol increased scCO2 extract yields at both low and high densities (7.6% w/v and 18.2% w/v, respectively). Additionally, the use of co-solvent increased this yield further under both low- and high-density conditions, to 13.7 and 19.1% w/v, respectively. Interestingly, higher scCO2 density (911 kg/m3) with and without ethanol did not improve the scCO2 extract yield or the amount of cannabinoids. Although this study provides new insights into the correlation between scCO2 density and ethanol co-extraction of CBD and THC, more studies are needed to determine how different scCO2 densities and co-solvents influence the extraction of cannabinoids.

Use of non-psychoactive residual biomass from Cannabis sativa L. for obtaining phenolic rich-extracts with antioxidant capacity

The present research aims to give an added value to the chain production of Cannabis sativa L plant, taking advantage of the non-psychoactive residual biomass (stems and leaves). Total phenolic content (TPC) and total antioxidant capacity (TAC) were analysed. A factorial design 2³ was carried out using extraction time (T), Particle size (PS), and solid-solvent ratio (SS) as factors. The extractions were made with ethanol at 96% as solvent. The maximum concentration of TPC found was 1264.61 mg GA/g DW at 6:250 g/mL, 8 h, and 109.28 µm for SS, T and PS, respectively. Similarly, the maximum TAC obtained was 0.467 mM Trolox equivalent, at 8 h, 6:250 g/mL and 109.28 µm for T, SS and PS, respectively. Additionally, the presence of oil was found in some samples of cannabis extracts for which FITR was performed, obtaining the presence of C-OH bonds associated with alcohols, phenols and possible cannabinoids.

Phytocannabinoids - An Overview of the Analytical Methodologies for Detection and Quantification of Therapeutically and Recreationally Relevant Cannabis Compounds

The legalization of the cultivation of low Δ9-tetrahydrocannabinol (Δ9-THC) and high cannabidiol (CBD) Cannabis Sativa plants is gaining momentum around the world due to increasing demand for CBD-containing products. In many countries where CBD oils, extracts and CBD-infused foods and beverages are being sold in health shops and supermarkets, appropriate testing of these products is a legal requirement. Normally this involves determining the total Δ9-THC and CBD and their precursor tetrahydrocannabinolic acids (THCA) and cannabidiolic acid (CBDA). As our knowledge of the other relevant cannabinoids expands, it is likely so too will the demand for them as additives in many consumer products ensuring a necessity for quantification methods and protocols for their identification. This paper discusses therapeutically relevant cannabinoids found in Cannabis plant, the applicability and efficiency of existing extraction and analytical techniques as well as the legal requirements for these analyses.

Processing and extraction methods of medicinal cannabis: a narrative review

INTRODUCTION

As the cannabis industry transitions from a black market to a legal market, product development, and methods of extraction have become a focal point. To date, more than thousands of chemical constituents have been identified from the cannabis plant, all of which possess different chemical properties that require different conditions for preservation during drying and extraction. However, scientific publications that explore these areas for the cannabis plant are currently lacking.

METHOD

This is a narrative review paper which focuses on critiquing drying and extraction methods of Cannabis sativa L. plant. Relevant keywords such as medicinal cannabis, extraction, solvent, cannabinoids, and terpenes have been searched in PubMed, EMBASE, MEDLINE, Google Scholar, and Cochrane Library (Wiley) databases.

RESULT

To find relevant papers for this narrative review, 93 papers have been reviewed. Among them, 12 irrelevant papers were discarded. The excluded papers were either about hemp seed oil or hemp fiber and protein. Based on this review, solvent extraction is the most common method for cannabis plants. Although solventless and hydrodynamic extraction are known for their high yield and feasibility, more investigation is needed in these areas. Regarding the drying process, hang-drying is the most convenient method; however, it may be substituted by freeze-drying in the near future.

DISCUSSION

This review analyses various drying and extraction processes to guide the selection of suitable methods for various types of cannabis products and applications. This is done by outlining traditional and modern methods of drying techniques, exploring the importance of solvents for extraction, visiting solventless extraction procedures, and finally comparing conventional and alternative methods of extraction.

CONCLUSION

In conclusion, based on the current knowledge, using organic solvents is the most convenient method for medicinal cannabis extraction. However, more research is needed for some of the drying and extraction methods. Also, developing a green and sustainable cannabis extraction method should be considered for future studies.

In vitro antioxidant and antibacterial activities with polyphenolic profiling of wild cherry, the European larch and sweet chestnut tree bark

This study is a comparative investigation of antioxidant and antibacterial properties of tree bark extracts of three common European species, Prunus avium L., Larix decidua Mill. and Castanea sativa Mill. The bioactive compounds present in the bark were recovered in 80% aqueous ethanol using ultrasound as the green extraction method. The antioxidant potential of the extracts was assessed with multiple biochemical assays: total phenol content (TPC) expressed in gallic acid equivalent (GAE), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) expressed in trolox equivalent (TE), and ferric reducing ability of plasma (FRAP) expressed in ascorbic acid equivalent (AAE). Sweet chestnut bark extract showed the highest antioxidant activity with TPC of 174.25 ± 16.95 mg GAE/g dry weight, DPPH (IC50) of 2.69 ± 0.03 μg/mL, ABTS of 739.65 ± 24.41 mg TE/g dry weight and FRAP of 207.49 ± 3.62 mg AAE/g dry weight. The antibacterial activity of the extracts was evaluated by disk diffusion test, minimal inhibitory concentration (MIC) assay and bacterial growth curves. Sweet chestnut bark extract gave IC50 values of 0.25 mg/mL and 1.00 mg/mL against E. coli and S. aureus, respectively. The polyphenolic profiling of the bark extracts was performed to identify the major compounds responsible for the bioactivities using high-performance liquid chromatography/tandem mass spectrometry (HPLC–MS/MS). The bark extracts were rich in natural antioxidants, thus holding tremendous potential for use as natural additives in food industry.

Graphic abstract

Extraction of Phenolic Compounds and Terpenes from Cannabis sativa L. By-Products: From Conventional to Intensified Processes

Cannabis sativa L. is a controversial crop due to its high tetrahydrocannabinol content varieties; however, the hemp varieties get an increased interest. This paper describes (i) the main categories of phenolic compounds (flavonoids, stilbenoids and lignans) and terpenes (monoterpenes and sesquiterpenes) from C. sativa by-products and their biological activities and (ii) the main extraction techniques for their recovery. It includes not only common techniques such as conventional solvent extraction, and hydrodistillation, but also intensification and emerging techniques such as ultrasound-assisted extraction or supercritical CO2 extraction. The effect of the operating conditions on the yield and composition of these categories of phenolic compounds and terpenes was discussed. A thorough investigation of innovative extraction techniques is indeed crucial for the extraction of phenolic compounds and terpenes from cannabis toward a sustainable industrial valorization of the whole plant.

Extraction of naturally occurring cannabinoids: an update

INTRODUCTION

Organic molecules that interact with the cannabinoid receptors are called cannabinoids, which can be endogenous, natural or synthetic compounds. They possess similar pharmacological properties as produced by the plant, Cannabis sativa L. Before cannabinoids can be analysed, they need to be extracted from the matrices.

OBJECTIVE

To review literature on the methods and protocols for the extraction of naturally occurring cannabinoids.

METHODOLOGY

An extensive literature search was performed incorporating several databases, notably, Web of Knowledge, PubMed and Google Scholar, and other relevant published materials. The keywords used in the search, in various combinations, with cannabinoids and extraction being present in all combinations, were Cannabis, hemp, cannabinoids, Cannabis sativa, marijuana, and extraction.

RESULTS

In addition to classical maceration with organic solvents, e.g. ethanol, pressurised solvent extraction, solvent heat reflux, Soxhlet extraction, supercritical fluid extraction, ultrasound-assisted extraction and microwave-assisted extraction, are routinely used nowadays for the extraction of cannabinoids from plant materials and cannabis consumer products. For the extraction of cannabinoids from biological samples, e.g. human blood, and also from food and beverages, and wastewater, solid-phase extraction and its variants, as well as liquid-liquid extraction are commonly used. Parameters for extraction can be optimised by response surface methodology or other mathematical modelling tools. There are at least six US patents on extraction of cannabinoids available to date.

CONCLUSIONS

Irrespective of the extraction method, extraction temperature, extraction time and extraction pressure play a vital role in overall yield of extraction. Solvent polarity can also be an important factor in some extraction methods.

Different Cannabis sativa Extraction Methods Result in Different Biological Activities against a Colon Cancer Cell Line and Healthy Colon Cells

Cannabis sativa is one of the oldest medicinal plants used by humans, containing hundreds of bioactive compounds. The biological effects and interplay of these compounds are far from fully understood, although the plant’s therapeutic effects are beyond doubt. Extraction methods for these compounds are becoming an integral part of modern Cannabis-based medicine. Still, little is known about how different methods affect the final composition of Cannabis extracts and thus, their therapeutic effects. In this study, different extraction methods were tested, namely maceration, Soxhlet, ultrasound-assisted extraction (UAE), and supercritical CO₂ extraction methods. The obtained extracts were evaluated for their cannabinoid content, antioxidant properties, and in vitro bioactivity on human colon cancer and healthy colon cells. Our data suggest that Cannabis extracts, when properly prepared, can significantly decrease cancer cell viability while protecting healthy cells from cytotoxic effects. However, post-processing of extracts poses a significant limitation in predicting therapeutic response based on the composition of the crude extract, as it affects not only the actual amounts of the respective cannabinoids but also their relative ratio to the primary extracts. These effects must be carefully considered in the future preparations of new therapeutic extracts.

Effective determination of the principal non-psychoactive cannabinoids in fiber-type Cannabis sativa L. by UPLC-PDA following a comprehensive design and optimization of extraction methodology

Cannabidiol (CBD) and cannabidiolic acid (CBDA) represent the most abundant non-psychoactive cannabinoids in fiber-type Cannabis sativa L. (hemp) and both have demonstrated high therapeutic potential. Hence, efficient extraction coupled with reliable determination of these compounds is crucial for informed utilization of hemp and is increasingly needed in the present state of harmonization efforts. In this context, a systematic approach for extraction optimization was followed, which initially involved comparison of three widely available extraction techniques, i.e. ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and dynamic maceration (DM). These were applied on samples of different hemp varieties (n = 3) using ethanol as a safe and efficient solvent. UAE showed the most promising results and was further optimized by means of response surface methodology (RSM), based on a circumscribed central composite design. The conditions maximizing CBD, CBDA, and total CBD content as well as extraction yield were determined with high desirability (0.97) and were experimentally confirmed. The optimized UAE method was also compared with a previously reported extraction procedure, demonstrating superior performance. For the quantitation of CBD and CBDA in hemp extracts, a reversed-phase UPLC-PDA method was developed and validated. Chromatographic separation was achieved in less than 10 min, while satisfactory results for linearity (R² > 0.996), precision (RSD < 2.0%), and accuracy (recovery rates of 93.1-101.0%) were obtained for both analytes. Limits of detection were determined as 0.07 and 0.04 μg mL^-1 for CBD and CBDA, respectively, indicating sufficient sensitivity. The good performance of the method was verified by the evaluation of additional parameters (e.g. matrix effect, extraction recovery), which was largely enabled by the use of isolated standards. The whole analytical workflow, involving both optimized UAE extraction and UPLC-PDA determination, entails simplified manipulation and may offer a reliable and cost-effective approach for routine quality control of hemp regarding the principal cannabinoids.

Extraction of medicinal cannabinoids through supercritical carbon dioxide technologies: A review

The pharmaceutical importance of cannabis is growing due to the natural non-psychoactive and psychoactive cannabinoids. For medicinal and forensic purposes, the effective extraction and quantification are essential to fully utilise the natural cannabinoids. The supercritical fluid extraction (SFE) process has gained increasing interest due to its selective extraction, short processing time (partly due to the efficient solvent removal process - supercritical fluid to vapour - leaving a solvent free product), low running cost, and low impact on the environment, compared to that of most conventional extraction methods. In this review, the extraction of cannabinoids through SFE methods have been summarised. The advantages of SFE of cannabinoids over conventional extraction procedures; such as microwave-assisted extraction, solid phase microextraction, hard-cap espresso, soxhlet extraction, high-throughput homogenization, ultrasound-assisted extraction, vacuum distillation of lipid-based extract, and liquid-liquid extraction are discussed. Furthermore, this review examines the importance of the SFE of cannabinoids by coupling with various conventional extraction methods, separation techniques, selection of a suitable co-solvent/modifier, and appropriate sample preparation. Additionally, the applications of using SFE technology and cannabinoids are reviewed with a focus on industrial, pharmaceutical, waste by-products, and purification.

Cannabinoids: Recent Updates on Public Perception, Adverse Reactions, Pharmacokinetics, Pretreatment Methods and Their Analysis Methods

Cannabinoids (CBDs) have been traditionally used as a folk medicine. Recently, they have been found to exhibit a high pharmacological potential. However, they are addicted and are often abused by drug users, thereby, becoming a threat to public safety. CBDs and their metabolites are usually found in trace levels in plants or in biological matrices and, are therefore not easy to be detected. Advances have been made toward accurately analyzing CBDs in plants or in biological matrices. This review aims at elucidating on the consumption of CBDs as well as its adverse effects and to provide a comprehensive overview of CBD pretreatment and detection methods. Moreover, novel pretreatment methods such as microextraction, Quick Easy Cheap Effective Rugged Safe and online technology as well as novel analytic methods such as ion-mobility mass spectrometry, application of high resolution mass spectrometry in nontarget screening are summarized. In addition, we discuss and compare the strengths and weaknesses of different methods and suggest their future prospect.

Positive Effect of Cannabis sativa L. Herb Extracts on Skin Cells and Assessment of Cannabinoid-Based Hydrogels Properties

The skin is an organ that is constantly exposed to many external factors that can affect its structure and function. Due to the presence of different cannabinoid receptors on many types of skin cells, cannabinoids can interact directly with them. Therefore, as part of this work, the impact of two types of Cannabis sativa L. herb extracts on keratinocytes and fibroblasts was assessed. The content of biologically active compounds such as phenols, flavonoids, chlorophylls and cannabinoids was evaluated. The antioxidant capacity of prepared extracts using the DPPH radical, H2DCFDA probe and measurement of superoxide dismutase activity was also assessed. The cytotoxicity of hemp extracts was determined using the Alamar Blue, Neutral Red and LDH assays. The ability of the extracts to inhibit the activity of matrix metalloproteinases, collagenase and elastase, was assessed. Preparations of model hydrogels were also prepared and their effect on transepidermal water loss and skin hydration was measured. The obtained results indicate that hemp extracts can be a valuable source of biologically active substances that reduce oxidative stress, inhibit skin aging processes and positively affect the viability of skin cells. The analysis also showed that hydrogels based on cannabis extracts have a positive effect on skin hydration.

‘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.

The Influence of Hemp Extract in Combination with Ginger on the Metabolic Activity of Metastatic Cells and Microorganisms

This study presents an investigation of the anticancer and antimicrobial ability of a combination of ginger and cannabis extracts in different ratios (1:1, 7:3 and 3:7). Extracts were obtained using various methods (Soxhlet extractions, cold macerations, ultrasonic extractions and supercritical fluid extractions). The antioxidant activity and the presence of total phenols were measured in the extracts, and the effect of the application extracts in various concentrations (c = 50, 20, 10, 5, 1, 0.1, 0.01 mg/mL) on cells was investigated. Higher values of antioxidants were measured at the ratio where ginger was predominant, which is reflected in a higher concentration of total phenols. Depending on the polyphenol content, the extracts were most effective when prepared supercritically and ultrasonically. However, with respect to cell response, the ratio was shown to have no effect on inhibiting cancer cell division. The minimum concentration required to inhibit cancer cell growth was found to be 1 mg/mL. High-performance liquid chromatography (HPLC) analysis also confirmed the effectiveness of ultrasonic and supercritical fluid extraction, as their extracts reached higher cannabinoid contents. In both extractions, the cannabidiol (CBD) content was above 30% and the cannabidiolic acid (CBDA) content was above 45%. In the case of ultrasonic extraction, a higher quantity of cannabigerol (CBG) (5.75 ± 0.18) was detected, and in the case of supercritical fluid extraction, higher cannabichromene (CBC) (5.48 ± 0.13) content was detected, when compared to other extraction methods. The antimicrobial potential of extracts prepared with ultrasonic and supercritical extractions on three microorganisms (Staphylococcus aureus, Escherichia coli and Candida albicans) was checked. Ginger and cannabis extract show better growth inhibition of microorganisms in cannabis-dominated ratios for gram-positive bacterium S. aureus, MIC = 9.38 mg/mL, for gram-negative bacterium E. coli, MIC > 37.5 mg/mL and for the C. albicans fungus MIC = 4.69 mg/mL. This suggests guidelines for further work: a 1: 1 ratio of ginger and hemp will be chosen in a combination with supercritical and ultrasonic extraction.

Emerging challenges in the extraction, analysis and bioanalysis of cannabidiol and related compounds

Cannabidiol (CBD) is a bioactive terpenophenolic compound isolated from Cannabis sativa L. It is known to possess several properties of pharmaceutical interest, such as antioxidant, anti-inflammatory, anti-microbial, neuroprotective and anti-convulsant, being it active as a multi-target compound. From a therapeutic point of view, CBD is most commonly used for seizure disorder in children. CBD is present in both medical and fiber-type C. sativa plants, but, unlike Δ⁹-tetrahydrocannabinol (THC), it is a non-psychoactive compound. Non-psychoactive or fiber-type C. sativa (also known as hemp) differs from the medical one, since it contains only low levels of THC and high levels of CBD and related non-psychoactive cannabinoids. In addition to medical Cannabis, which is used for many different therapeutic purposes, a great expansion of the market of hemp plant material and related products has been observed in recent years, due to its usage in many fields, including food, cosmetics and electronic cigarettes liquids (commonly known as e-liquids). In this view, this work is focused on recent advances on sample preparation strategies and analytical methods for the chemical analysis of CBD and related compounds in both C. sativa plant material, its derived products and biological samples. Since sample preparation is considered to be a crucial step in the development of reliable analytical methods for the determination of natural compounds in complex matrices, different extraction methods are discussed. As regards the analysis of CBD and related compounds, the application of both separation and non-separation methods is discussed in detail. The advantages, disadvantages and applicability of the different methodologies currently available are evaluated. The scientific interest in the development of portable devices for the reliable analysis of CBD in vegetable and biological samples is also highlighted.

Response surface optimization of the water immersion extraction and macroporous resin purification processes of anhydrosafflor yellow B from Carthamus tinctorius L

In this study,based on a developed high performance liquid chromatographic quantitative method, the suitable extraction and purification conditions of anhydrosafflor yellow B (AHSYB) from safflower were determined by response surface methodology. The optimal water immersion extraction parameters were as follows: liquid to solid ratio of 22:1; extraction temperature of 75 °C; extraction time of 35 min. Under these conditions, the maximum extraction yield of AHSYB reached 0.465%. The aqueous extract was further purified by HPD-300 macroporous resin. The optimum adsorption conditions were: pH 2.8; adsorption flow rate of 1.9 mL/min; solution concentration of 0.06 g/mL. The optimum desorption conditions were: ethanol concentrations of 74%; desorption flow rate of 1.6 mL/min; elution volume of 4.4 BV. Under these conditions, the maximum adsorption ratio and desorption ratio reached 1.095 and 0.906 mg/g, respectively. The content of AHSYB reached 6.83%, which was 2.91 times higher than that before purification. PRACTICAL APPLICATION: The suitable conditions for water immersion extraction and macroporous resin purification of AHSYB are first determined, which facilitates the further utilization of AHSYB as a food and drug.

Microwave-Assisted Industrial Scale Cannabis Extraction

Cannabis is a flowering plant that has long been used for medicinal, therapeutic, and recreational purposes. Cannabis contains more than 500 different compounds, including a unique class of terpeno-phenolic compounds known as cannabinoids. Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most extensively studied cannabinoids. They have been associated with the therapeutic and medicinal properties of the cannabis plant and also with its popularity as a recreational drug. In this paper, an industrial method for cannabis extraction using 915 MHz microwaves coupled with continuous flow operation is presented. The main advantages of the microwave-assisted extraction (MAE) are associated to the continuous-flow operation at atmospheric pressure which allows for higher volumes of biomass to be processed in less time than existing extraction methods, with improved extraction efficiency leading to increased final product yields, improved extract consistency and quality because the process does not require stopping and restarting material flows, and ease of scale-up to industrial scale without the use of pressurised batch vessels. Moreover, due to the flexibility of changing the operation conditions, MAE eliminates additional steps required in most extraction methods, such as biomass decarboxylation or winterisation, which typically adds at least a half day to the extraction process. Another factor that sets MAE apart is the ability to achieve high extraction efficiency, i.e., up to 95% of the active compounds from cannabis biomass can be recovered at industrial scale.

Development of extraction technique and GC/FID method for the analysis of cannabinoids in Cannabis sativa L. spp. santicha (hemp)

INTRODUCTION

Nowadays, the interest in industrial Cannabis sativa L. herb has been increasing in the world. As a result, it is becoming one of the most studied plants due to its multifunctional benefits.

OBJECTIVES

To the best of our knowledge, no study has been conducted so far to determine the impact of extraction methods and conditions on the extraction yields of CBD and CBG from the Cannabis sativa L. ssp. Santhica. Therefore, we aimed to investigate a simple and sensitive GC-FID method to determine CBD and CBG in hemp extract.

METHODS

As regards sample preparation, three extraction techniques were compared, including maceration (ME), ultrasound-assisted extraction (UAE) and reflux-heat extraction (RHE), in order to obtain a high recovery of the CBD of interest from the plant material. The GC-FID method developed in this study represents a powerful tool for the extraction and analysis of non-psychoactive cannabinoids from hemp varieties to be used for the preparations of extracts with a high content of bioactive compounds for both pharmaceutical and nutraceutical applications.

RESULTS

A simple extraction procedure for CBD and CBG from hemp was also optimized in this work, by using ultrasound assisted extraction method with 96% ethanol, material/solvent ratio 1:10 and extraction time 10 min at room temperature.

CONCLUSION

The overall analytical method was fully validated in agreement with international guidelines. Therefore, proving a powerful and reliable tool for both the selection of hemp varieties with a high content of bioactive compounds and the quality control of its derivatives.

Optimization of Ultrasound-Assisted Extraction Using Response Surface Methodology for Simultaneous Quantitation of Six Flavonoids in Flos Sophorae Immaturus and Antioxidant Activity

Ultrasound-assisted extraction (UAE) was applied to extract rutin (RU), nicotiflorin (NI), narcissoside (NA), kaempferol (KA), isorhamnetin (IS), quercetin (QU), and total flavonoids of Flos Sophorae Immaturus (TFFSI) from Flos Sophorae Immaturus (FSI). Through single factor test and response surface methodology (RSM), the optimal extraction conditions were concluded as follows: ethanol concentration 70%, time 30 min, temperature 61 °C, and liquid/solid ratio 15.30 mL/g, respectively. The actual extraction rates of RU, NI, NA, KA, IS, QU, and TFFSI were 14.6101%, 2.9310%, 7.1987%, 0.1041%, 0.4920%, 2.7998%, and 26.4260%, respectively. The experimental results demonstrated that the extraction method with accuracy and efficiency could be used for the comprehensive evaluation quality control of extracts from FSI. The antioxidant activities of hydroalcoholic extraction from FSI on 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•⁺), superoxide anion (•O²⁻) free radicals, and ferric reducing/antioxidant power (FRAP) were assessed. The results showed that the antioxidation activities of extracts on DPPH, ABTS•⁺, and •O²⁻ free radicals were reached 89.29%, 97.86%, and 56.61%, and 81.4% in FRAP at 1.0 mg/mL, respectively. The antioxidant capacity of FSI extract was positively correlated with the amount of total flavonoids.

Selective Extraction of Cannabinoid Compounds from Cannabis Seed Using Pressurized Hot Water Extraction

Phytochemicals of Cannabis sativa mainly for the use in the different industries are that of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Pressurized hot water extraction (PHWE) is seen as an efficient, fast, green extraction technique for the removal of polar and semi-polar compounds from plant materials. The PHWE technique was applied to extract cannabinoid compounds from Cannabis sativa seed. Response surface methodology was used to investigate the influence of extraction time (5-60 min), extraction temperature (50-200 °C) and collector vessel temperature (25-200 °C) on the recovery of delta-9-tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD), cannabichromene (CBG) and cannabigerol (CBC) from Cannabis sativa seed by PHWE. The identification and semi quantification of cannabinoid compounds were determined using GCXGC-TOFMS. The results obtained from different extractions show that the amount of THC and CBN was drastically decreasing in the liquid extract when the temperature rose from 140 to 160 °C in the extraction cell and the collector's vessel. The optimal conditions to extract more CBD, CBC, and CBG than THC and CBN were set at 150 °C, 160 °C and 45 min as extraction temperature, the temperature at collector vessel, and the extraction time, respectively. At this condition, the predicted and experimental ratio of THCt (THC + CBN)/CBDt (CBD + CBC+ CBG) was found to be 0.17 and 0.18, respectively. Therefore, PHWE can be seen as an alternative to the classic extraction approach as the efficiency is higher and it is environmentally friendly.

Simultaneous Optimization of Ultrasound-Assisted Extraction for Flavonoids and Antioxidant Activity of Angelica keiskei Using Response Surface Methodology (RSM)

Angelica keiskei Koidzumi (A. keiskei), as a Japanese edible herbal plant, enjoys a variety of biological activities due to the presence of numerous active compounds, especially flavonoids. This study aims for the optimization of ultrasound-assisted extraction (UAE) for flavonoids in A. keiskei and their antioxidant activity by using the response surface methodology (RSM). Single-factor experiments and a four-factor three-level Box-Behnken design (BBD) were performed to explore the effects of the following parameters on flavonoid extraction and antioxidant activity evaluation: ultrasonic temperature (X1), ultrasonic time (X2), ethanol concentration (X3) and liquid-solid ratio (X4). The optimum conditions of the combination of total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity (DPPH-RSC) and ferric-reducing antioxidant power (FRAP) were as follows: X1 = 80 °C, X2 = 4 min, X3 = 78%, X4 = 35 mL/g, respectively. The experimental results provide a theoretical basis for the extensive utilization of A. keiskei and flavonoids extraction from A. keiskei as a potential source of antioxidants.

Extractions of Medical Cannabis Cultivars and the Role of Decarboxylation in Optimal Receptor Responses

Introduction: Phytocannabinoids, characteristic compounds produced by medical cannabis, interact with cannabinoid (CB) receptors (CB1 and CB2) as well as other receptor systems to exhibit their corresponding pharmacological effects. In their natural form, CBs such as Δ9-tetrahydrocannabinolic acid and cannabidiolic acid are inactive at these receptors, while their decarboxylated forms (Δ9-tetrahydrocannabinol and cannabidiol, respectively) are potent ligands at CB receptors. Thus, extraction and processing of medical cannabis for active constituents are important. Purpose and Methods: Patients consuming medical cannabis often have limited alternative treatment options and in recent years, medical cannabis extracts have been popular as a substitute for dried cannabis plants, despite limited studies on these derivatives. We investigated three disparate cannabis cultivars and compared four chemical extraction methods head to head, viz. Soxhlet, ultrasound-assisted supercritical fluid, and microwave-assisted extractions, for their efficiency. We further characterized the chemical compositions of these extracts. Results: Microwave extraction consistently produced completely decarboxylated phytocannabinoid extracts. Factors such as temperature and exposure time play important roles in the decarboxylation of phytocannabinoids, thereby generating pharmacologically active CBs, and these conditions may differ for each cannabis cultivar. Conclusion: Chemical consistency and potency due to active compounds are in turn important in producing consistent and reliable medical cannabis extracts and their derivatives. These processes must be subject to higher levels of scientific rigor as the patient population around the world are seeking the help of such extracts for various clinical conditions, and as medical cannabis industry is receiving acceptance in various countries.