WO2019211795A1

WO2019211795A1 - Continuous flow microwave-assisted extraction of a cannabis biomass

Info

Publication number: WO2019211795A1
Application number: PCT/IB2019/053608
Authority: WO
Inventors: Steven Splinter; Tomasz Popek; Harmandeep KAUR; Anna BAKOWSKA-BARCZAK
Original assignee: Radient Technologies Inc
Current assignee: Radient Technologies Inc
Priority date: 2018-05-03
Filing date: 2019-05-02
Publication date: 2019-11-07
Anticipated expiration: 2020-11-03

Abstract

A method and apparatus for extracting pharmacologically active ingredients with increased yield and purity from a cannabis biomass is disclosed. The method comprises providing a raw cannabis biomass containing target compounds for extraction. The raw cannabis biomass may be ground or pulverized to obtain a prepared cannabis biomass. Slurry may be prepared by adding a solvent to the prepared cannabis biomass. The solvent may be selected based on different dielectrics and solvent parameter properties. The slurry may be heated in a continuous flow microwave-assisted extraction apparatus to obtain an extract. The microwave-assisted extraction apparatus may include one or more sensor that may monitor the temperature, pressure, and/or residence time of the slurry. Successively, the spent biomass and the extract may be separated from the slurry. The extract may be treated to obtain a final formulation containing the target compounds in sufficiently high yield and high purity. The spent biomass may be processed to yield less than 0.3% concentration of cannabinoids naturally produced by plants.

Description

CONTINUOUS FLOW MICROWAVE-ASSISTED EXTRACTION OF A CANNABIS BIOMASS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present patent application claims the priority benefit of U.S. provisional patent application number 62/666,439 filed May 3, 2018 and U.S. provisional patent application number 62/666,490 filed May 3, 2018, the disclosures of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field Of The Disclosure

[0002] The present disclosure is generally related to a method and apparatus for processing cannabis biomass to increase yield and purity of cannabis extract and a composition of cannabis biomass of less than 0.3% concentration of one or more cannabinoids.

2. Description of the Related Art

[0003] Cannabis is a genus belonging to the family of cannabaceae. Three common species include Cannabis sativa, Cannabis indica, and Cannabis ruderalis. The genus has been indigenous to Central Asia and the Indian subcontinent. Cannabis has a long history being used for medicinal, therapeutic, and recreational purposes. The importance of cannabis in therapeutics is emphasized by the ever-increasing number of research publication related to the new indications for cannabis. For example, pharmaceutical research companies are presently developing new natural cannabinoid formulations and delivery systems to meet various regulatory requirements. Cannabis is known, for example, to be capable of relieving nausea (such as that accompanying chemotherapy), pain, vomiting, spasticity in multiple sclerosis, and increase hunger in anorexia.

[0004] The term cannabis or "cannabis biomass" encompasses the Cannabis sativa plant and also variants thereof, including subspecies sativa, indica and ruderalis, cannabis cultivars, and cannabis chemovars (varieties characterised by chemical composition), which naturally contain different amounts of the individual cannabinoids, and also plants which are the result of genetic crosses. The term "cannabis biomass" is to be interpreted accordingly as encompassing plant material derived from one or more cannabis plants.

[0005] Cannabis biomass contains a unique class of terpeno-phenolic compounds known as cannabinoids or phytocannabinoids, which have been extensively studied since the discovery of the chemical structure of tetrahydrocannabinol (D-9-THC), commonly known as THC. Over 113 phytocannabinoids have been identified. Such cannabinoids are generally produced by glandular trichomes that occur on most aerial surfaces of the plant. The cannabinoids are biosynthesized in the plant in acidic forms known as acidic cannabinoids. The acidic cannabinoids may be slowly decarboxylated during drying of harvested plant material.

Decarboxylation may be hastened by heating the cannabis biomass, such as when the cannabis biomass is smoked or vaporized.

[0006] The principle cannabinoids present in cannabis are the D-9-tetrahydrocannabinolic add (D-9-THCA) and cannabidiolic acid (CBDA). The D-9-THCA does not have its own psychoactive properties as is, but may be decarboxylated to D-9-tetrahydrocannabinol (D-9- THC), which is the most potent psychoactive cannabinoid among known cannabinoids. The neutral form of CBDA is cannabidiol (CBD), which is a major cannabinoid substituent in hemp cannabis. CBD is non-psychoadive and is widely known to have therapeutic potential for a variety of medical conditions. The proportion of cannabinoids in the plant may vary from species to species, as well as vary within the same species at different times and seasons.

Furthermore, the proportion of cannabinoids in a plant may further depend upon soil, climate, and harvesting methods. Thus, based on the proportion of the cannabinoids present in a plant variety, the psychoactive and medicinal effects obtained from different plant varieties may vary.

[0007] Depending upon the psychoactive and medicinal effects obtained from different varieties of the cannabis plant or the different methods of cultivation for cannabis, a specific variety of cannabis may be considered more effective or potent than others (c.g., in providing the desired physiological effect at a desired level in an individual). Similarly, some specific combinations of pharmacologically active compounds in a cannabis variety may be more desirable in comparison to other varieties. When preparing cannabis plant extracts, the retention of the full mix of cannabinoids present in the original plant may be desirable for some varieties, while other varieties may be preferred in altered form due to the variances in the specific cannabinoid composition and concentrations. Such variance is further exacerbated by the presence of certain terpenoid or phenolic compounds, which may have pharmacological activity of their own and which may be desired at different concentrations in different combinations.

[0008] Historical delivery methods have involved smoking ( e.g ., combusting) the dried cannabis plant material. Smoking results, however, in adverse effects on the respiratory system via the production of potentially toxic substances. In addition, smoking is an inefficient mechanism that delivers a variable mixture of active and inactive substances, many of which may be undesirable. Alternative delivery methods such as ingesting typically require extracts of the cannabis biomass (also known as cannabis concentrates or cannabis oils). Often, cannabis extracts are formulated using any convenient pharmacologically acceptable diluents, carriers or excipients to produce a composition. Raw cannabis biomass may also be more susceptible to possible biological contaminants such as fungi and bacteria than extracts.

[0009] Previously, compounds may be extracted from cannabis by using conventional methods of extraction, such as maceration, decoction, or solvent extraction. Such conventional methods may suffer from various limitations and disadvantages (e.g., extraction times may be very high so as to be impractical to scale). For example, subjecting the biomass to a prolonged extraction process may risk modification of the plant profile, negative effects on terpenes, or otherwise cause other undesirable effects that lower the quality or purity of the end product. Traditional methods of extraction may therefore hamper quality and purity of the final product. Further, final concentrated or purified active compounds are often diluted or dispersed into an oil, fat or other lipid-based excipient or carrier to a desired concentration for certain uses (e.g., in a pharmaceutical, food, or cosmetic formulation).

[0010] Other methods such as supercritical fluid extraction (SFE) make use of supercritical fluids to selectively remove compounds from solid, semisolid, and liquid matrices in a batch process. SFE is, however, dangerous and requires very high pressures to be employed (> 70 atm). In addition, SFE is also inefficient and therefore not conducive to high throughputs, as well as environmentally damaging (e.g., producing large amounts of the greenhouse gas carbon dioxide as a by-product). [0011] Cannabis smoking has been the topic of a number of clinical and basic research studies, which have focused on the mechanism of the addictive processes and the health hazards associated with cannabis use. One of the major drawbacks in these studies has been the unavailability of placebo cannabis cigarettes depleted of A9-THC (i.e., a control), and research cannabis cigarettes containing standardized amounts of A9-THC. These studies have been further complicated by a lack of quantitative information on the effective delivery of A9-THC resulting from the varied and unpredictable amount of A9-THC usually found in cannabis cigarettes. The current art further shows harmful effects of smoked cannabis i.e., cannabinoid effects may not be separated from effects of inhaling smoke from burning plant materials and contaminants.

[0012] Various cultivars of cannabis sativa contain an amount of active compounds

(cannabinoids, e.g. A9-THC) ranging from approximating 5% to 20% by weight. In 1 gram of cannabis, that translates to 50 mg - 200 mg of active compound. An efficient solvent extraction method may extract over 95% of the active compounds, leaving 2.5 mg - 10 mg remaining in the biomass. The amount of the D-9-THC in the depleted cannabis mass may be comparable to industrial hemp, a variety of cannabis sativa, which may contain less than 0.3% D-9-THC by weight, or 3 mg D-9-THC per gram. Further, as per cannabis industry, a common dosage of D-9- THC should be equal or greater than 10 mg. However, the depleted cannabis biomass may contain less D-9-THC than may be required for a normal dose of the D-9-THC, and is functionally inactive. Conventional methods of extracting compounds from cannabis biomass, including SFE, may not be sufficiently efficient so as to deplete the cannabis biomass of D-9- THC to a residual level such that the extracted biomass is comparable to industrial hemp and is functionally inactive. For example, a cultivar of cannabis containing approximately 10% of D-9- THC, and for which approximately 20% of the cannabis biomass is comprised of extractable resin, an extraction efficiency (percent recovery of available D-9-THC) of 90% would result in a depleted cannabis biomass containing approximately 1.25% of D-9-THC and so still may be functionally active. Further, a cultivar of cannabis containing approximately 10% of D-9-THC, and for which approximately 20% of the cannabis biomass is comprised of extractable resin, an extraction efficiency (percent recovery of available D-9-THC) of 95% would result in a depleted cannabis biomass containing approximately 0.63% of D-9-THC and so still may be functionally active [0013] Thus, there is a need for improved methods and systems for extracting various compounds from cannabis biomass that may be more efficient and provide higher quality and quantity of cannabis extract from a given biomass.

SUMMARY OF THE CLAIMED INVENTION

[0014] Embodiments of the present invention provide a method for processing cannabis biomass to increase yield and purity of cannabis extract. The method comprises providing a raw cannabis biomass containing target compounds for extraction. The raw cannabis biomass may be ground or pulverized to obtain a prepared cannabis biomass. Slurry may be prepared by adding a solvent to the prepared cannabis biomass. The solvent may be selected based on different dielectrics and solvent parameter properties. The slurry may be heated in a continuous flow microwave assisted extraction apparatus to obtain an extract. The microwave-assisted extraction apparatus may include one or more sensor that may monitor the temperature, pressure, and/or residence time of the slurry. Successively, the spent biomass and the extract may be separated from the slurry. The extract may be treated to obtain a final formulation containing the target compounds in sufficiently high yield and high purity. The spent biomass may be processed to yield less than 0.3% concentration of cannabinoids naturally produced by plants.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a block diagram representation of an exemplary system for extracting pharmacologically active ingredients with increased yield and purity from a cannabis biomass.

[0016] FIG. 2 is a flow chart illustrating an exemplary method for extracting

pharmacologically active ingredients with increased yield and purity from cannabis biomass.

[0017] FIG. 3 is a block diagram representation of an exemplary extraction process where various sensors are placed at different locations thereof.

[0018] FIG. 4 is a block diagram representation of exemplary post-extraction processing of separated spent biomass from solvent using a variety of mechanical separation processes.

[0019] FIG. 5 is a table of test data of concentrations of target compounds present in raw biomass of different cultivars of cannabis.

[0020] FIG. 6 is a table of test data obtained for different solvent to biomass ratios used for optimal extraction of target compounds from the biomass, according to an embodiment.

[0021] FIG. 7 is a table of test data of concentrations of THC found in the biomass at different stages of processing.

[0022] FIG. 8A is a table of test data of concentrations of cannabinoids obtained at different temperature related to the processing.

[0023] FIG. 8B is a table of test data of concentrations of CBDA obtained at different extractor residence time values related to the processing.

[0024] FIG. 9 is a table showing an analysis of the concentration of compounds present in various samples of decarboxylated cannabis biomass.

[0025] FIG. 10 is a table showing an analysis of the concentration of compounds present in spent biomass after extraction for the decarboxylated cannabis biomass.

DETAILED DESCRIPTION

[0026] Embodiments of the present invention provides a method for processing cannabis biomass to increase yield and purity of cannabis extract. The method comprises providing a raw cannabis biomass containing target compounds for extraction. The extract may be treated to obtain a final formulation containing the target compounds in sufficiently high yield and high purity.

[0027] Method of extracting pharmacologically active compounds from cannabis biomass will now be explained with reference to various units shown in the block diagram of FIG. 1 and the flow chart 200 of FIG. 2. FIG. 1 is a block diagram representation of an exemplary system 100 for extracting pharmacologically active compounds from biomass, and FIG. 2 is a flow chart illustrating an exemplary method 200 for extracting pharmacologically active compounds from biomass.

[0028] The term 'pharmacologically active ingredients' may henceforth be used

interchangeably with the term 'target compounds.' One skilled in the art will appreciate that, for this and other processes and methods disclosed herein, the functions performed in the processes and methods may be implemented in differing order. Furthermore, the outlined steps and operations are only provided as examples, and some of the steps and operations may be optional, combined into fewer steps and operations, or expanded into additional steps and operations without detracting from the essence of the disclosed embodiments.

[0029] System 100 of FIG. 1 includes a raw biomass holding chamber 102, into which a raw biomass may be provided in step 202 of FIG. 2. The raw biomass may contain target compounds for extraction. The raw biomass may be present in the form of dried, ground, non- decarboxylated or decarboxylated flowers (buds) of cannabis plant. Any part of the cannabis biomass that contains cannabinoids can be used or included in the raw biomass that is provided to raw biomass holding chamber 102. In some embodiments, the average particle size of the raw biomass may range between 0.5 - 10 mm. The raw biomass may contain target compounds that need to be extracted. In one embodiment, the raw biomass may be heated to approximately 125° C for approximately 45 minutes to decarboxylate the cannabinoid carboxylic acids into neutral cannabinoid forms. The mass of decarboxylated cannabis following such treatment may get reduced ( e.g ., 11.7% weight loss). In an embodiment, the raw biomass may be dried, non- decarboxylated cannabis biomass. In another embodiment, the raw biomass may be fresh, non- dried, non-decarboxylated cannabis biomass.

[0030] Successively in step 204, the raw biomass may be sampled and analyzed in sampling chamber 120. In a preferred embodiment, the raw biomass may be analyzed to determine cannabinoid content and a cannabinoid profile (of the specific cannabinoids and concentrations thereof) of the sampled raw biomass. The raw biomass may be sampled and analyzed using several methods. Such analysis may be performed using an Ultra High-performance Liquid Chromatography coupled with Mass Spectrometry (UPLC-MS) detection technique. Further, a terpene profile of the raw biomass may be determined using a Gas Chromatography-Mass Spectrometry Detection (GC-MS). The sampling and analysis techniques may help in determining the cannabinoid content and the cannabinoid profile of the raw biomass (i.e., THC, THCA, CBD, CBDA or total cannabinoids present in the provided biomass).

[0031] Further in step 206, the raw biomass may be ground into small particles to obtain a prepared biomass in biomass preparation chamber 104. The prepared biomass may then be provided from biomass preparation chamber 104 to a prepared biomass holding chamber 106.

[0032] The prepared biomass may be used to form a slurry in step 208. The slurry may be formed in a slurry formation chamber 108 where one or more solvents may be added to the prepared biomass from a solvent holding chamber 110. The solvent added to the prepared biomass may be selected with different dielectric and solvent parameter properties. The solvent may be selected from an alcohol group, alkane group, and ketone group, or mixtures of such with water, stored in a solvent holding chamber 110. The prepared biomass may be combined with the solvent to form the slurry. The solvent-to-biomass ratio may be maintained at approximately 5-10 1/kg to ease pumping operation of the slurry. In an embodiment, the solvent-to-raw biomass ratio may be maintained as low as possible.

[0033] Thereafter, the slurry may be transferred from the slurry formation chamber 108 to an extraction chamber 112 where such slurry is subject to heat at step 210. The slurry may be transported using a set of mechanical conveyors ( e.g ., slurry pump, screw conveyor or worm gear). In the extraction chamber 112, the slurry may be subjected to a thermal process, such as provided by a microwave generator 114.

[0034] In one case, the slurry may be transported into an extraction chamber 112 through a tube. Extraction chamber 112 may include a portion that is microwave transparent, which may allow microwaves ( e.g ., generated using a magnetron of microwave generator 112) to pass through and heat the slurry inside the extraction chamber 112. The slurry may be heated within the extraction chamber 112 to a certain temperature by exposing the slurry to the microwave to a predefined time with a predefined microwave energy density range. In a preferred embodiment, the slurry may be heated to a temperature range of 20 - 75° C with a contact time of 1 - 30 minutes, and microwave energy density range of 0.1 - 10 kW/kg. Such heating may facilitate the extraction of various (pharmacologically active) compounds from the prepared biomass into the solvent. In a preferred embodiment the conditions of temperature, time and microwave energy density may be determined by the results of the sampling and analysis of the biomass and carefully controlled to maximize purity and yield of the cannabis extract.

[0035] Post heating the slurry and extraction of compounds from the biomass, the now- spent biomass and solvent(s) may be transferred to separation chamber 116, where the slurry is subject to filtration and separation at step 212. Such filtration and separation within filtration unit 116 may result in isolating the slurry components from each other: the spent biomass and the solvent(s) containing the extracted compounds. Once isolated, the spent biomass and the solvent(s) containing the extracted compounds may be transferred into spent biomass storage unit 118 and solvent recovery chamber 122, respectively. The separation process may be performed using one or more of several methods, such as filtration, centrifugation, and other similar processes.

[0036] In an embodiment, the spent biomass may be sampled at step 214. Sampling of the spent biomass may be performed in a sampling chamber 120. The spent biomass may be sampled and analyzed to determine remaining cannabinoid content and cannabinoid profile. The spent biomass may be sampled and analyzed using several methods. The analysis may be performed using an Ultra High Performance Liquid Chromatography coupled with Mass Spectrometry detection (UPLC-MS). Further, terpene profile of the spent biomass may be determined using a Gas Chromatography-Mass Spectrometry Detection (GC-MS). The sampling and analytical techniques may help in determining cannabinoid content and profile of the spent biomass (e.g., THCA, THC, CBDA, CBD, and total cannabinoids).

[0037] Post sampling and analysis of the spent biomass, the waste spent biomass may be incinerated or mixed with a deactivating agent for disposal. The disposal may be done using a disposal system 128. In one case, clay may be used as the deactivating agent. [0038] An extract/solvent mixture may first be separated from the spent biomass, and the solvent may then be separated from the extract/solvent mixture and recovered by a solvent recovery chamber 122 at step 216. As a result, a desolventized extract may be obtained. The solvent may be recovered from the extract/solvent mixture by a distillation or evaporation process, so that the solvent may be used in another extraction process. In a preferred embodiment the solvent may be removed using a thin film vacuum evaporation process such as wiped film evaporation.

[0039] Post separation from the spent biomass, the active compounds may then be combined with a carrier fluid 130 or excipients or other additives ( e.g ., medium chain triglycerides) to form a formulated extract. The formulation— combination of the extracts with a carrier fluid or excipients— may be performed in a formulation chamber 124.

[0040] Successively, the final formulated extract may be obtained at step 218. The resulting formulation product may then be provided to a product holding chamber 126. The heated formulated extract may be formulated into final formulated extract using at least one of a plurality of formulation methods. In some embodiments, the inactive acidic cannabinoids may be activated (decarboxylated) by heating the final formulated extract.

[0041] Thereafter, sampling of the formulation product may be performed at step 220. Sampling of the formulated extract may be performed in the sampling chamber 120. The formulated extract may comprise A-9-THC, A-9-THCA, CBDA, CBD, other cannabinoids, terpenes, or other medicinal value compounds. The final formulated extract may be sampled and analyzed using several techniques. In a preferred embodiment, analysis of the final formulated extract may be performed to determine cannabinoid content and cannabinoid profile. The analysis may be performed using an Ultra High Performance Liquid

Chromatography coupled with Mass Spectrometry detection (UPLC-MS). Terpene profile of the final formulated extract may be determined using a Gas Chromatography-Mass Spectrometry Detection (GC-MS). The sampling and analytical techniques may help in determining the content and profile of the final formulated extract (i.e. THC, THCA, CBD, CBDA or total cannabinoids).

[0042] FIG. 3 illustrates various sensors placed at different locations during the extraction process. The sensors may be placed at various stages of processing to assess temperature, pressure, elapsed time, and other parameters. FIG. 3 illustrates a portion of the process depicted in FIG. 1 and potential placement of example monitoring devices. Temperature of slurry entering the slurry formation chamber 108 may be monitored using a slurry temperature sensor 302. As the slurry is transported into the extractor 112, pressure of the incoming slurry may be monitored using an incoming slurry pressure sensor 304. The slurry may be heated to a certain temperature by exposing the slurry to the microwave 114, for a predefined time, with a predefined microwave energy range in the extractor 112. The extractor residence time sensor 306 may monitor an amount of time for which the slurry may be heated in the extractor 112. An extractor output temperature sensor 308 may monitor temperature of the slurry and an extractor output pressure sensor 310 may monitor pressure of the slurry, before the slurry is filtered and separated by the filtration unit 116.

[0043] FIG. 4 illustrates various post-extraction processing to separate spent (already extracted) biomass from solvent using a variety of mechanical separation processes. Post extraction, the spent biomass may be separated from the solvent using a mechanical separation process 402. The mechanical separation process may include filtration, centrifugation, or any similar method known in the art. A spent biomass 404 may be obtained from the mechanical separation 402. Following this separation, the spent biomass may contain some residual solvent and potentially target compounds. These compounds may be removed using solvent washing, solvent evaporation or chemical neutralization 406. The solvent used for washing may be subjected to additional processes to recover target compounds. The spent biomass may further be processed using vacuum and temperature treatments 408, such as drying and lyophilization (e.g. freeze-drying), to obtain a final spent biomass product 410.

[0044] The final spent biomass product 410 may be utilized in agricultural or industrial applications requiring non-toxic material that is absorbent and highly fibrous like animal litter, animal feed, and mulch.

[0045] In an embodiment, post the mechanical separation process 402, the solvent may contain the extracted target compounds; these may undergo a chemical or physical treatment 412 for improving purity through removal of less desirable compounds. The solvent may be removed by a solvent recovery process 414 using chemical, pressure, or temperature-based methods, such as vacuum distillation or vacuum evaporation. A formulation 416 obtained post solvent recovery 414 may then contain the target compounds at high purity. Further, compounds may be combined with appropriate diluents, carrier materials, excipients, scents, flavorings, or other elements to create a formulated extract 418 for the desired application. In an exemplary embodiment, THC may be present in a concentration of, for example, 20 g/1 directly following the extraction step. Following centrifugation and vacuum evaporation, the THC may be present in a concentration of, for example, 70% w/w. In a final formulation step, the THC may be diluted into a medium-chain triglyceride carrier oil to concentration of, for example, 30 g/1·

[0046] FIG. 5 illustrates test data of concentrations of target compounds present in raw biomass of different cultivars (also referred to as strains) of cannabis. The target compounds in the raw biomass may be measured using a variety of analytic testing devices, including gas chromatographs, high performance liquid chromatographs, or mass spectrometers. Raw biomass may constitute dried, fresh, or frozen cannabis biomass. In some embodiments, the cannabis biomass may be comprised of cannabis flowers, leaves, stems or roots or some combination of these. In one embodiment, cannabis may be harvested from various cultivars and locations and under different conditions. To ensure high purity of target compounds, the biomass may be sampled and inspected using chemical, mechanical, or optical methods.

[0047] In an exemplary embodiment, FIG. 5 illustrates test data related to various samples collected from different cultivars (strains). In one case, Cultivar A collected from locationl, on 23 April may contain a concentration of 5.3% THCA w/w (w/w represents the % weight of the compound divided by the total weight) 0.1% THC w/w, and total cannabinoid concentration of 6.5% w/w. In another case, Cultivar A collected from location 1, on 04 July may contain a concentration of 4.1% THCA w/w, 0.04% THC w/w, and total cannabinoid concentration of 4.2% w/w. Further, Cultivar B collected from location 1, on 16 October may contain a concentration of 13.7% THCA w/w, 0.7% THC w/w, and total cannabinoid concentration of 14.8% w/w. In another case, Cultivar C collected from location 1, on 6 November may contain a concentration of 11.7% THCA w/w, 0.2% THC w/w, and total cannabinoid concentration of 12.4% w/w. In one case, Cultivar D collected from location 1, on 14 November may contain a concentration of 14% THCA w/w, 0.2% THC w/w, and total cannabinoid concentration of 14.7% w/w.

[0048] In an exemplary embodiment, FIG. 6 illustrates test data obtained for different solvents and solvent-to-biomass ratios used for optimal extraction of target compounds from the biomass. Extraction of the target compounds from the biomass may occur in a solvent. The solvent may be varied to ensure high-yield, high-quality extraction of the target compounds from the specific biomass type. In some embodiments, alcohols may be used to extract compounds. The solvent may be for example ethanol (C2H5OH), isopropyl alcohol (IP A, C3H7OH), and the like. In some embodiments, the solvent may be an alkane, such as liquefied butane or pentane.

[0049] In an exemplary embodiment, FIG. 6 also illustrates various solvents used with the samples collected from various locations. For first sample, Cultivar A collected from location 1, on 23 April was extracted with ethanol as a solvent. 4 grams of biomass mass used with 24 mL of solvent volume, resulted in a recovery of 70% of the available THCA present in the biomass. For the second sample, Cultivar A collected from locationl, on 30 April was extracted with ethanol as the solvent. In one case, 4 grams of biomass used with 32 mL of solvent volume, resulted in a recovery of 90% of available THCA. In another case, Cultivar A collected from location 1, on 23 April, was extracted with pentane as a solvent. In one case, 4 grams of biomass mass used with 32 mL of solvent volume, resulted in a recovery of 93% of available THCA. In another case Cultivar A collected from location 1, on 04 July, was extracted with polyethylene glycol as a solvent. In one case, 4 grams of biomass mass used with 32 mL of solvent volume, resulted in a recovery of 78% of available THCA.

[0050] FIG. 7 illustrates test data of concentrations of THC found in the biomass at different stages of processing. Samples taken from various inputs and outputs of the process may be analyzed. Optical, chemical, or mechanical methods may be utilized to assess purity of the target compounds. Raw biomass may indicate harvested organic materials; spent biomass may indicate organic matter subjected to extraction and separated from the solvents; formulation may indicate final target compounds following removal of both spent biomass and residual solvent. A sample of material collected at any of these process stages may be assessed for a compound of interest.

[0051] In an exemplary embodiment, FIG. 7 illustrates THC content concentrations found in samples collected at different stages of the processing. In one case, 14% concentration of THC was found to be present in the raw biomass. In another case, 0.8% concentration of THC was found to be present in the spent biomass. In another case, 72% concentration of THC was found to be present in the final formulation. [0052] FIG. 8A illustrates test data of concentrations of THCA or CBDA obtained at different temperatures related to the processing, according to an embodiment. FIG. 8B illustrates test data of concentrations of THCA or CBDA obtained at different extractor residence time values related to the processing. Sensors may monitor temperature, flow rate, or residence time. Extractor residence time may indicate a total amount of time for which a specific volume of slurry is exposed to the microwave extraction process. The presence of extractor residence time monitoring sensors may ensure residence time is optimized for both high levels of extraction and maximum throughput without damage to any target compounds.

[0053] In an exemplary embodiment, FIG. 8A illustrates % cannabinoid recovery at various input slurry temperatures and extractor output temperatures. For sample Run 06, at an input slurry temperature of 23°C and an extractor output temperature of 23°C, 86% of THCA recovery was determined. For sample Run03 at an input slurry temperature of 23°C and an extractor output temperature of 27°C, 93% of THCA recovery was determined. For sample Run07 at an input slurry temperature of 23°C and an extractor output temperature of 40°C, 85% of CBDA recovery was determined. In one case, for sample Run08 an input slurry temperature of 22°C and an extractor output temperature of 60°C, 91% of THC recovery was determined.

[0054] In an exemplary embodiment, FIG. 8B illustrates CBDA % recovery at different extractor residence times. For sample Run09 with an extractor residence time of 5 min, 83% CBDA recovery was determined. In another case, sample RunOlO with an extractor residence time of 10 min, 90% CBDA recovery was determined. Further, in one case sample Runll with an extractor residence time of 20 min, 83% THC recovery was determined.

[0055] In one embodiment, to enable sampling of the process inputs and outputs, pressure sensors may be located at various points within the process. In this example, pressure of the slurry may be measured before the slurry enters into microwave extractor and again after the extraction run is complete. A net change in the pressure may be calculated from the sensor readings. Pressure adjustments may be made to prevent process upsets and improve product consistency.

[0056] In one embodiment, extraction of the target compounds may be performed in a microwave extractor, where power of the microwaves could be adjusted. The biomass-solvent slurry flows through a chamber while being subjected to the microwaves. Thus, duration of the slurry residence time in the extractor may be a function of both the slurry flow rate and length and volume of the chamber through which the slurry travels. Adjustment of the microwave parameters, the flow rate, or the chamber dimensions may be utilized to permit maximum extraction of the target compounds, while limiting extraction of less desirable compounds and minimizing run time.

[0057] In a preferred embodiment, sampling and analysis of the spent biomass may be performed to determine the cannabinoid content and the cannabinoid profile in the composition of the extracted (spent) cannabis biomass. The composition of the cannabis biomass may include one or more cannabinoids having a total concentration of less than 0.3%. The cannabinoids may be naturally produced by plants, and may be selected from a group consisting of tetrahydrocannabinol (THC), Tetrahydrocannabinolic acid (THCA), Tetrahydrocannabivarin (THCV), Cannabidiol (CBD), Cannabigerol (CBG), cannabinol (CBN), and Cannabichromene (CBC). Further, the composition may include one or more terpenoids having a total concentration of less than 3%. The one or more terpenoids may be naturally produced by the plants, and may be selected from a group consisting of Limonene, Humulene, Pinene, Linalool, Caryophyllene, and Myrcene, for example. It should be noted that the composition may contain low terpenes (i.e., the one or more terpenoids) in order to have low odor and/or flavor. Further, the composition may include one or more flavonoids naturally produced by the plants having a total concentration of less than 3%. Further, the composition of the cannabis biomass may include 20 - 80% concentration of original chlorophyll, cellulose, and non-active compounds. It should be noted that the composition of the cannabis biomass may include cannabis sativa biomass depleted of A-9-T1TC below a specific threshold.

[0058] FIG. 9 illustrates a table showing an analysis of the concentration of compounds present in various samples of decarboxylated cannabis biomass a comparison made between concentrations of compounds present in various samples of non-decarboxylated cannabis biomass at a biomass preparation step. The various samples may include sample 1, sample 2, and sample 3. Sample 1 of the cannabis biomass may have been analyzed by U1TPLC to contain 10.88% of THCA, 2.36% of THC, 11.90% of Total THC equivalents, 0.48% of CBDA, non- detectable CBD and 0.42% of Total CBD equivalents. Similarly, sample 2 of the cannabis biomass may have been analyzed to contain 9.46% of THCA, 1.79% of THC, 10.09% of Total THC equivalents, 3.63% of CBDA, 0.52% of CBD and 3.71% of Total CBD equivalents. Similarly, sample 3 of the cannabis biomass may have been analyzed to contain 7.50% of THCA, 2.68% of THC, 9.26% of Total THC equivalents, 2.93% of CBDA, 1.06% of CBD and 3.62% of Total CBD equivalents. It should be noted that the total THC equivalents (and similarly, Total CBD equivalents) may be calculated using the following formula:

Total THC equivalents = THC + THCA * 0.877

[0059] FIG. 10 illustrates a table showing an analysis of spent biomass after extraction for the decarboxylated cannabis biomass sample 1 and 2. In an exemplary embodiment, a slurry may be formed from the decarboxylated biomass in a slurry formation unit by adding ethanol to the prepared biomass. Successively the slurry may be transferred to an extractor. The ethanol to biomass ratio may be maintained at approximately 10 1 per kg and the residence time maintained at approximately 18 minutes by controlling the mass flow of the biomass and the solvent to the extractor. Heating of the slurry may be affected by application of microwave energy. The microwave energy density may be carefully controlled. Post heating the slurry, the spent biomass and extract mixture may be separated by stages of centrifugation and filtration. The spent biomass may be washed with additional ethanol solvent during centrifugation. As shown in FIG. 10, the analysis of the spent biomass sample 1 for the non-decarboxylated cannabis biomass may have been analyzed by UHPLC to contain 0.17% of THCA, 0.14% of THC, 0.29% of Total THC equivalents, 0.09% of CBDA, 0.06% of CBD and 0.14% of Total CBD equivalents. The analysis of the spent biomass sample 2 for the non-decarboxylated cannabis biomass may have been analyzed by UHPLC to contain 0.18% of THCA, 0.14% of THC, 0.30% of Total THC equivalents, 0.09% of CBDA, 0.06% of CBD and 0.14% of Total CBD equivalents. It should be noted that after extraction, the concentration of THC is less than 0.3% which for cannabis may be considered non-psychoactive, for example, industrial hemp (i.e. a cultivar of cannabis sativa that naturally produces less than 0.3% A-9-THC). The extraction efficiency necessary to achieve a residual concentration of THC in the spent biomass may be greater than 95%.

[0060] The composition of the cannabis biomass may be an intermediate product for one or more use cases such as, but not limited to, a placebo cigarette with characteristics of cannabis plant without any active compounds (i.e., negligible quantities of A-9-THC), and a carrier mass for a specific concentration and/or blends of the one or more cannabinoids, the one or more terpenoids, and the one or more flavonoids, by 'spiking' the composition with the extracted compounds. Further, the composition of the cannabis biomass may be used as adjuvant drugs for anti-inflammatory and analgesic treatment, especially for chronic and terminal pain, neuropathic pain symptoms in humans and in animals. Further, the composition may be used as a raw material for various goods such as paper, fabrics, rope, and livestock feed, etc. by further processing the composition. Further, the composition may be sufficiently depleted of TFIC that it may not be considered to be a controlled substance.

[0061] The foregoing detailed description of the technology has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the technology to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. The described embodiments were chosen in order to best explain the principles of the technology, its practical application, and to enable others skilled in the art to utilize the technology in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the technology be defined by the claim.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A method for extracting pharmacologically active ingredients with increased purity and yield from a cannabis biomass, the method comprising:

preparing a raw cannabis biomass, wherein the prepared cannabis biomass includes particles;

forming a slurry by adding a solvent to the prepared cannabis biomass;

extracting one or more cannabinoid components from the slurry using a continuous flow microwave-assisted extraction apparatus; and

separating the extracted cannabinoid components from a spent biomass.

2. The method of claim 1, wherein preparing the raw cannabis biomass includes at least one of grinding, milling, chopping, or sorting of the raw cannabis biomass.

3. The method of claim 1, wherein the solvent includes at least one of alcohols, alkanes, and ketones.

4. The method of claim 1, further comprising use of one or more sensors that monitor at least one of temperature, pressure, and residence time of the slurry in the microwave portion of the continuous flow microwave-assisted extraction apparatus.

5. The method of claim 4, wherein at least one of the sensors detects a pressure of the slurry entering an extraction chamber.

6. The method of claim 4, wherein at least one of the sensors detects a duration of extraction in the microwave portion of the continuous flow microwave-assisted extraction apparatus.

7. The method of claim 4, wherein at least one of the sensors detects a temperature and pressure of the extractor output.

8. The method of claim 1, wherein separating the extracted cannabinoid components from a spent biomass includes at least one of separation, filtration, concentration, acidification, basification, drying, and packaging.

9. The method of claim 1, wherein the raw cannabis biomass consists of tetrahydrocannabinol carboxylic acid (THCA) and tetrahydrocannabinol (THC) concentration ranging between 0.3- 40%.

10. The method of claim 1, wherein the raw cannabis biomass consists of cannabidiolic acid (CBDA) and cannabidiol (CBD) concentration ranging between 0.3-40%.

11. The method of claim 1, wherein the components are extracted from the slurry according to a contact time ranging between 1 - 15 minutes.

12. The method of claim 1, wherein the components are extracted from the slurry according to a contact time ranging between 16-30 minutes.

13. The method of claim 1, wherein a volume quantity of the solvent ranges between 3 - 15 1/kg of biomass.

14. The method of claim 1, further comprising processing the spent biomass to remove pharmacologically active compounds.

15. The method of claim 1, further comprising processing the extract to increase concentration of pharmacologically active compounds.

16. The method claim 15, further comprising combining the extracted cannabinoid components with carrier fluid to form a formulated extract.

17. The method claim 16, wherein the carrier fluid includes at least one of: polyunsaturated fatty acid (PUFA), corn oil, safflower oil, borage oil, flax oil, canola oil, cottonseed oil, soybean oil, olive oil, sunflower oil, coconut oil, palm oil, avocado oil, monoglycerides, diglycerides, triglycerides, medium chain or long chain triglycerides, lecithin, limonene, essential oils of spices, herbs or other plants, fish oil, glycerol, and glycols.

18. A composition of cannabis biomass, the composition comprising:

less than 0.3% concentration of one or more cannabinoids naturally produced by plants.

19. The composition of claim 18 further comprising:

less than 3% concentration of one or more terpenoids naturally produced by the plants; and

less than 3% concentration of one or more flavonoids naturally produced by the plants.

20. An apparatus for extracting pharmacologically active ingredients with increased purity and yield from a cannabis biomass, the apparatus comprising:

an extraction chamber that holds a slurry that includes a cannabinoid biomass and a solvent;

a microwave generator that generates microwaves that are applied to the slurry, wherein the microwaves enhance extraction of one or more active cannabinoids from the cannabinoid biomass into the solvent;

at least one sensor, wherein the at least one sensor monitors data including at least one of duration, pressure or temperature of the slurry;

a separation chamber that separates a spent cannabinoid biomass from the slurry, wherein the separated solvent now further includes the extracted active cannabinoids.