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It has been used in an entheogenic context — a chemical substance used in a religious , shamanic , or spiritual context  - in the Indian subcontinent since the Vedic period dating back to approximately BCE, but perhaps as far back as BCE. There are several references in Greek mythology to a powerful drug that eliminated anguish and sorrow.
Herodotus wrote about early ceremonial practices by the Scythians , thought to have occurred from the 5th to 2nd century BCE. In modern culture the spiritual use of cannabis has been spread by the disciples of the Rastafari movement who use cannabis as a sacrament and as an aid to meditation.
The earliest known reports regarding the sacred status of cannabis in the Indian subcontinent come from the Atharva Veda estimated to have been written sometime around — BCE.
Cannabis is consumed in many different ways: Acute effects may include anxiety and panic, impaired attention and memory, an increased risk of psychotic symptoms, [b] the inability to think clearly, and an increased risk of accidents. Those with THC in their system were from three to seven times more likely to be the cause of the accident than those who had not used either cannabis or alcohol, although its role is not necessarily causal because THC stays in the bloodstream for days to weeks after intoxication.
According to the United States Department of Health and Human Services, there were , emergency room visits associated with cannabis use in These statistics include visits in which the patient was treated for a condition induced by or related to recent cannabis use. The drug use must be "implicated" in the emergency department visit, but does not need to be the direct cause of the visit. Most of the illicit drug emergency room visits involved multiple drugs. The short term effects of cannabis can be altered if it has been laced with opioid drugs such as heroin or fentanyl.
Heavy, long-term exposure to marijuana may have biologically based physical, mental, behavioral and social health consequences and may be "associated with diseases of the liver particularly with co-existing hepatitis C , lungs, heart, and vasculature". A limited number of studies have examined the effects of cannabis smoking on the respiratory system. Cannabis smoke contains thousands of organic and inorganic chemical compounds. This tar is chemically similar to that found in tobacco smoke,  and over fifty known carcinogens have been identified in cannabis smoke,  including; nitrosamines, reactive aldehydes, and polycylic hydrocarbons, including benz[a]pyrene.
Evidence for causing these cancers is mixed concerning heavy, long-term use. In general there are far lower risks of pulmonary complications for regular cannabis smokers when compared with those of tobacco. There is concern that cannabis may contribute to cardiovascular disease,  but as of , evidence of this relationship was unclear. If cannabis arteritis turns out to be a distinct clinical entity, it might be the consequence of vasoconstrictor activity observed from deltaTHC and deltaTHC.
Research in these events is complicated because cannabis is often used in conjunction with tobacco, and drugs such as alcohol and cocaine. Although global abnormalities in white matter and grey matter are not associated with cannabis abuse, reduced hippocampal volume is consistently found. Amygdalar abnormalities are sometimes reported, although findings are inconsistent. Cannabis use is associated with increased recruitment of task-related areas, such as the dorsolateral prefrontal cortex , which is thought to reflect compensatory activity due to reduced processing efficiency.
The magnitude of down regulation is associated with cumulative cannabis exposure, and is reversed after one month of abstinence. A meta analysis found that, although a longer period of abstinence was associated with smaller magnitudes of impairment, both retrospective and prospective memory were impaired in cannabis users.
The authors concluded that some, but not all, of the deficits associated with cannabis use were reversible. The study following the largest number of heavy cannabis users reported that IQ declined between ages 7—13 and age Poorer school performance and increased incidence of leaving school early were both associated with cannabis use, although a causal relationship was not established.
At an epidemiological level, a dose response relationship exists between cannabis use and increased risk of psychosis    and earlier onset of psychosis. It is not clear whether cannabis use affects the rate of suicide. Cannabis abuse disorder in the DSM-V involves a combination of DSM-IV criteria for cannabis abuse and dependence, plus the addition of craving, minus the criterion related to legal troubles.
THC, the principal psychoactive constituent of the cannabis plant, has low toxicity. Cannabis has not been reported to cause fatal overdose in humans.
The high lipid-solubility of cannabinoids results in their persisting in the body for long periods of time. Not until the end of the 20th century was the specific mechanism of action of THC at the neuronal level studied. These actions can be blocked by the selective CB 1 receptor antagonist rimonabant SR , which has been shown in clinical trials to be an effective treatment for smoking cessation , weight loss , and as a means of controlling or reducing metabolic syndrome risk factors.
Via CB 1 receptor activation, THC indirectly increases dopamine release and produces psychotropic effects. THC and its major inactive metabolite, THC-COOH, can be measured in blood, urine, hair, oral fluid or sweat using chromatographic techniques as part of a drug use testing program or a forensic investigation of a traffic or other criminal offense.
These tests cannot, however, distinguish authorized cannabis smoking for medical purposes from unauthorized recreational smoking. The Duquenois—Levine test is commonly used as a screening test in the field, but it cannot definitively confirm the presence of cannabis, as a large range of substances have been shown to give false positives.
A review found that the THC content in marijuana had increased worldwide from to It is likely that the higher THC content allows people to ingest less tar. At the same time, CBD levels in seized samples have lowered, in part because of the desire to produce higher THC levels and because more illegal growers cultivate indoors using artificial lights.
This helps avoid detection but reduces the CBD production of the plant. The stalks and seeds have "much lower THC levels". After revisions to cannabis scheduling in the UK, the government moved cannabis back from a class C to a class B drug. A purported reason was the appearance of high potency cannabis. Marijuana or marihuana herbal cannabis ,  consists of the dried flowers and subtending leaves and stems of the female Cannabis plant. Although herbal cannabis and industrial hemp derive from the same species and contain the psychoactive component THC , they are distinct strains with unique biochemical compositions and uses.
Hemp has lower concentrations of THC and higher concentrations of CBD, which decreases the psychoactive effects  . Kief is a powder, rich in trichomes ,  which can be sifted from the leaves and flowers of cannabis plants and either consumed in powder form or compressed to produce cakes of hashish. Hashish also spelled hasheesh, hashisha, or simply hash is a concentrated resin cake or ball produced from pressed kief, the detached trichomes and fine material that falls off cannabis flowers and leaves.
It varies in color from black to golden brown depending upon purity and variety of cultivar it was obtained from. Cannabinoids can be extracted from cannabis plant matter using high- proof spirits often grain alcohol to create a tincture , often referred to as "green dragon". Hash oil is a resinous matrix of cannabinoids obtained from the Cannabis plant by solvent extraction ,  formed into a hardened or viscous mass. There are many varieties of cannabis infusions owing to the variety of non-volatile solvents used.
Examples of solvents used in this process are cocoa butter, dairy butter, cooking oil, glycerine , and skin moisturizers. Depending on the solvent, these may be used in cannabis foods or applied topically.
Medical marijuana refers to the use of the Cannabis plant as a physician-recommended herbal therapy as well as synthetic  THC and cannabinoids.
So far, the medical use of cannabis is legal only in a limited number of territories, including Canada,  Belgium , Australia, the Netherlands , Spain, and many U. This usage generally requires a prescription, and distribution is usually done within a framework defined by local laws. There is evidence supporting the use of cannabis or its derivatives in the treatment of chemotherapy-induced nausea and vomiting, neuropathic pain, and multiple sclerosis. Lower levels of evidence support its use for AIDS wasting syndrome, epilepsy, rheumatoid arthritis, and glaucoma.
Cannabis is indigenous to Central Asia  and the Indian subcontinent,  and its use for fabric and rope dates back to the Neolithic age in China and Japan. Cannabis was known to the ancient Assyrians , who discovered its psychoactive properties through the Iranians. Cannabis has an ancient history of ritual use and is found in pharmacological cults around the world.
Hemp seeds discovered by archaeologists at Pazyryk suggest early ceremonial practices like eating by the Scythians occurred during the 5th to 2nd century BC, confirming previous historical reports by Herodotus. AD were found to have traces of cannabis. Following an — travel in North Africa and the Middle East, French physician Jacques-Joseph Moreau wrote on the psychological effects of cannabis use; he was a member of Paris' Club des Hashischins.
Cannabis was criminalized in various countries beginning in the 19th century. The British colonies of Mauritius banned cannabis in over concerns on its effect on Indian indentured workers;  the same occurred in British Singapore in In , a compromise was made at an international conference in The Hague about the International Opium Convention that banned exportation of "Indian hemp" to countries that had prohibited its use, and requiring importing countries to issue certificates approving the importation and stating that the shipment was required "exclusively for medical or scientific purposes".
It also required parties to "exercise an effective control of such a nature as to prevent the illicit international traffic in Indian hemp and especially in the resin". In , the Dutch government divided drugs into more- and less-dangerous categories, with cannabis being in the lesser category.
Accordingly, possession of 30 grams or less was made a misdemeanor. Other types of sales and transportation are not permitted, although the general approach toward cannabis was lenient even before official decriminalisation.
In Uruguay, President Jose Mujica signed legislation to legalize recreational cannabis in December , making Uruguay the first country in the modern era to legalize cannabis. In August , Uruguay legalized growing up to six plants at home, as well as the formation of growing clubs, and a state-controlled marijuana dispensary regime. As of October 17, when recreational use of cannabis was legalized in Canada, dietary supplements for human use and veterinary health products containing not more than 10 parts per million of THC extract were approved for marketing; Nabiximols as Sativex is used as a prescription drug in Canada.
The United Nations' World Drug Report stated that cannabis "was the world's most widely produced, trafficked, and consumed drug in the world in ", and estimated between million and million users globally in Since the beginning of the 20th century, most countries have enacted laws against the cultivation, possession or transfer of cannabis. Many jurisdictions have lessened the penalties for possession of small quantities of cannabis so that it is punished by confiscation and sometimes a fine, rather than imprisonment, focusing more on those who traffic the drug on the black market.
In some areas where cannabis use had been historically tolerated, new restrictions were instituted, such as the closing of cannabis coffee shops near the borders of the Netherlands,  and closing of coffee shops near secondary schools in the Netherlands. Simple possession can carry long prison terms in some countries, particularly in East Asia, where the sale of cannabis may lead to a sentence of life in prison or even execution.
In December , the U. At least cities across California have enacted bans in recent years. In December , Uruguay became the first country to legalize growing, sale and use of cannabis. In November , Uttarakhand became the first state of India to legalize the cultivation of hemp for industrial purposes. On October 17, , Australian health minister Sussan Ley presented a new law that will allow the cultivation of cannabis for scientific research and medical trials on patients.
As the drug has increasingly come to be seen as a health issue instead of criminal behavior, marijuana has also been legalized or decriminalized in: Between and , eleven states decriminalized marijuana. In the US, men are over twice as likely to use marijuana as women and year-olds are six times more likely to use as over year-olds.
Marijuana use in the United States is three times above the global average, but in line with other Western democracies. It is often claimed by growers and breeders of herbal cannabis that advances in breeding and cultivation techniques have increased the potency of cannabis since the late s and early '70s when THC was first discovered and understood. However, potent seedless cannabis such as " Thai sticks " were already available at that time. Sinsemilla Spanish for "without seed" is the dried, seedless inflorescences of female cannabis plants.
Because THC production drops off once pollination occurs, the male plants which produce little THC themselves are eliminated before they shed pollen to prevent pollination. Advanced cultivation techniques such as hydroponics , cloning , high-intensity artificial lighting , and the sea of green method are frequently employed as a response in part to prohibition enforcement efforts that make outdoor cultivation more risky.
It is often cited that the average levels of THC in cannabis sold in the United States rose dramatically between the s and , but such statements are likely skewed because undue weight is given to much more expensive and potent, but less prevalent samples.
It is a cross-breed of Cannabis sativa and C. The price or street value of cannabis varies widely depending on geographic area and potency. The Gateway Hypothesis states that cannabis use increases the probability of trying "harder" drugs. The hypothesis has been hotly debated as it is regarded by some as the primary rationale for the United States prohibition on cannabis use. Some studies state that while there is no proof for the gateway hypothesis,  young cannabis users should still be considered as a risk group for intervention programs.
The gateway effect may appear due to social factors involved in using any illegal drug. Because of the illegal status of cannabis, its consumers are likely to find themselves in situations allowing them to acquaint with individuals using or selling other illegal drugs. In turn alcohol and tobacco are easier to obtain at an earlier point than is cannabis though the reverse may be true in some areas , thus leading to the "gateway sequence" in those individuals since they are most likely to experiment with any drug offered.
An alternative to the gateway hypothesis is the common liability to addiction CLA theory. It states that some individuals are, for various reasons, willing to try multiple recreational substances. The "gateway" drugs are merely those that are usually available at an earlier age than the harder drugs.
Researchers have noted in an extensive review that it is dangerous to present the sequence of events described in gateway "theory" in causative terms as this hinders both research and intervention. Cannabis research is challenging since the plant is illegal in most countries. There are also other difficulties in researching the effects of cannabis. Many people who smoke cannabis also smoke tobacco. Another difficulty researchers have is in recruiting people who smoke cannabis into studies.
Because cannabis is an illegal drug in many countries, people may be reluctant to take part in research, and if they do agree to take part, they may not say how much cannabis they actually smoke. A review found that the use of high CBD-to-THC strains of cannabis showed significantly fewer positive symptoms such as delusions and hallucinations, better cognitive function and both lower risk for developing psychosis, as well as a later age of onset of the illness, compared to cannabis with low CBD-to-THC ratios.
Cannabis use started to become popular in the United States in the s. Private use of cannabis was legalized in September after a unanimous decision by the Constitutional Court in Johannesburg. Media related to Cannabis at Wikimedia Commons.
From Wikipedia, the free encyclopedia. Cannabis A flowering cannabis plant. Medical cannabis from state-controlled production: Anlage III , other cannabis: Schedule I legal in 9 states for recreational use UN: Entheogenic use of cannabis. Long-term effects of cannabis. History of cannabis and Timeline of cannabis law.
Prohibition of drugs and Drug liberalization. Illegal but often unenforced. Marijuana and the Cannabinoids. Retrieved 13 December Retrieved 12 January Retrieved 28 September Retrieved 9 October Retrieved 17 July American Heritage Dictionary of the English Language. See also article on Marijuana as a word. Spanish Word Histories and Mysteries: Pharmacology, Toxicology, and Therapeutic Potential. National Institute on Drug Abuse.
Retrieved 19 April Retrieved 12 July Manual of forensic emergency medicine: Jones and Bartlett Publishers. World Drug Report Retrieved 26 June Retrieved 9 September Retrieved 30 October National Conference of State Legislatures. Retrieved 3 July Retrieved 19 October National Institute of Drug Abuse. The term medical marijuana refers to using the whole unprocessed marijuana plant or its basic extracts to treat a disease or symptom.
Retrieved 8 September A Systematic Review and Meta-analysis". Current Pain and Headache Reports. The Brain and Body's Marijuana and Beyond.
Archived from the original PDF on 30 April British Journal of Hospital Medicine. Cannabis Use and Dependence: Public Health and Public Policy. Cannabis in Medical Practice: University of Virginia Medical Center. Cannabinoid function in learning, memory and plasticity. Handbook of Experimental Pharmacology. Marijuana Cannabis sativa L.
Medical Toxicology of Drug Abuse: Synthesized Chemicals and Psychoactive Plants. Retrieved 14 July The American Journal on Addictions. Retrieved 1 November Are All These Hoops Necessary? The sum of squared errors SSE are 0. In these recent years, the development of flavor and fragrance industries are remarkably fast due to the rapid development of food, cosmetics, and perfume industries. Thousands of new artificial flavor and fragrance compounds have also been produced to fulfill high demand for food, cosmetics, and perfume industries.
Different flavor substances can be found in natural products, and most of them have high economic value. One of them is acetophenone. Collin, "Aroma extraction dilution analysis of Sauternes wines. Key role of polyfunctional thiols", J.
There are numbers of natural products contain acetophenone such as apple, apricot, banana, and cauliflower [ 2 P. Gutierrez, "Phenolic-compound-extraction system for fruit and vegetable samples", J. The extraction process using organic solvent may be the most commonly used methods to obtain the acetophenone from natural products.
However, this method possesses several disadvantages such as low purity and requires several stages of purification of the resulting product [ 4 C. Patent 2,, , Extraction using supercritical CO 2 is one of viable alternatives that can be used in aroma and fragrance industries.
The working procedures are relatively straightforward and produce high extraction yields with high purity, and shorter extraction time [ 4 C. Another advantage of using supercritical fluid is the elimination of subsequent separation processes such as distillation and crystallization.
For the design of the supercritical extraction process of acetophenone from the natural matrices, the equilibrium or solubility data of acetophenone-supercritical CO 2 is needed. Currently, several literatures [ 5 A. Maurer, "High-pressure vapor liquid equilibria in binary mixtures of carbon dioxide and aromatic hydrocarbons: Sharafeev, "Waste management in propylene epoxidation process with the use of supercritical fluid media", Am.
Bamberger and Maurer [ 5 A. The determination of the solubility of aromatic hydrocarbons in supercritical carbon dioxide was conducted gravimetrically. The measurements were performed at temperatures between K and K at pressures up to 18 MPa. Recently, Gumerov et al. They used dynamic flow method to extract and to obtain the solubility those hydrocarbons, and one of the hydrocarbons was acetophenone.
Since all of the previous studies emphasized on the dynamic system, in the current study we focused on the combination of static system and gravimetrically method. Therefore, one of the objectives of this study is to obtain the solubility data of acetophenone on supercritical carbon dioxide at various pressures and temperatures. To obtain the solubility data of compounds in the supercritical fluid SCF in a wide range of pressures and temperatures, is tedious, expensive, and time consuming work.
In most cases, the data obtained from the experiments usually only valid in a narrow range of pressures and temperatures. To overcome this problem, usually a mathematical model which valid for a wide range of pressures and concentrations is needed. This mathematical model is usually developed from the limiting number of experimental data. In this paper, we employed density based models Chrastil and Del Valle — Aguilera and equation of state EoS approach Peng-Robinson to correlate the experimental solubility data of acetophenone in supercritical carbon dioxide.
The solubilities of acetophenone in supercritical carbon dioxide were measured at four different temperatures Acetophenone C 8 H 8 O is a yellow liquid with a boiling point of Acetophenone used in this study was obtained as analytical standard and supplied by Sigma-Aldrich CAS no: Food grade carbon dioxide with the purity of Analytical grade ethanol was used to dissolve the acetophenone in the sample collector.
In order to control and maintain the temperature, oven memmert Germany was used. Another part of the system was equilibration column Swagelok, USA. The entire components, fittings, and tubing used in the system were made of stainless steel Swagelok, USA. The maximum working pressure and temperature of the supercritical system was 30 MPa and The solubility of acetophenone in supercritical CO 2 was obtained in the static mode.
Brief descriptions of the experimental procedure are described as follow [ 7 S. Ismadji, "Solubility of methyl salicylate in supercritical carbon dioxide at several temperatures", J. The oven was turned on, and the system was heated until the desired temperature was reached After the thermal equilibrium condition had been reached, the liquid CO 2 was pumped to the equilibration column using a high pressure pump.
Since the static method was used in this study, during the processes, valves V-2 was closed, while valves V-1 was kept open. After the equilibrium condition had been achieved, then the sampling tube was disconnected from the system by closing valve V The sample in the sampling tube was released by opening valve V-2 to the collector containing a known amount of ethanol to fully separate acetophenone and carbon dioxide.
At least three replicated samples were taken at the experimental condition, and equilibrium composition was determined by averaging the replications. The concentration of acetophenone in ethanol was determined by means of a Shimadzu gas chromatograph GC provided with a flame ionization detector. Gas chromatography was calibrated externally using acetophenone solutions with different concentrations.
Schematic diagram of supercritical apparatus. Liquid CO2 cylinder; 2. High pressure pump; 3. Digital pressure indicator; 5. The operational conditions for GC are described as follows: DB Wax; 2 oven: The solubilities of acetophenone in supercritical CO 2 were measured at temperatures ranging from The experimental solubility data of acetophenone in supercritical carbon dioxide are given in Table 1 and also plotted in Fig. The densities of carbon dioxide at several pressures and temperatures were predicted using Stryjek and Vera modification of the Peng-Robinson equation of state [ 8 R.
An improved peng-robinson equation of state for pure compounds and mixtures", Can. Experimental solubility of acetophenone in supercritical CO 2 as a function of pressure at different temperatures: Where P and V are pressure and molar volume, respectively, R is the gas constant; T c and P c are the critical temperature and critical pressure of the pure component, respectively. From the experimental data shown in Fig. This phenomenon can be explained by the effect of the solvent density on the solubility of the solute at supercritical condition: The solubility data of acetophenone in supercritical CO 2 expressed in mole fraction are ranging from 0.
Below crossover region, the solubility of acetophenone in supercritical carbon dioxide decreases with increasing temperature, but above the crossover region, the opposite phenomenon is observed. The crossover region was observed at a pressure range between 11 and 16 MPa. This phenomenon can be explained by two crucial factors density of the SCF and the solute vapor pressure which affected by the change of temperature. As the temperature increases, the density of SCF decreases but the solute vapor pressure increases.
These two factors have the tendency of opposite effects on the solubility curve. The effect of density seems to be dominant in the low pressure region and cause the decrease of the solute solubility as the temperature increases, while, the solute vapor pressure seems to be dominant in the high pressure region hence the solute solubility increased as the temperature increases [ 9 M. Krukonis, Supercritical Fluid Extraction: Principles and Practices , Butterworths: Huang, "Kawl, and Y.
The density-based equations, are the most widely used models to correlate the solubility of various compounds in supercritical fluids, due to its simplicity and do not require any critical physical properties. The earliest known of the density based model was developed by Chrastil [ 12 J. Chrastil, "Solubility of solids and liquids in supercritical gases", J. He developed the model based on the theory of the solvato complex formation in equilibrium, one molecule of solute A associates with k molecules of solvent B to form a solvato complex AB k.
His semiempirical model has the mathematical form as follows:. Parameter a is a constant, which depends on the heat of vaporization and solvation enthalpies of the solute. Parameter b is a function of the association number and the molecular weights of the solute and supercritical fluids. This parameter is not affected by changing of temperature [ 12 J. In order to obtain the parameters k, a , and b , the fitting of the solubility experimental data was conducted for all temperatures simultaneously using a nonlinear least square method by minimizing the following sum of squared errors as the objective function.
Where C exp is the experimental solubility of acetophenone in supercritical CO 2 , C cal is the calculated solubility, and N is the number of experimental data.
Table 2 represents the fitting parameters values and the sum of squared errors of Chrastil equation. Table 2 and Fig. The sum of the squared error value of the data fitting is 0. Chrastil plot of acetophenone solubility in scCO 2 as a function of temperature and density.
From the value of parameter a in the Table 2 , the total enthalpies of vaporization and solvation of the solute can be estimated to be
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Limonene was the principal component extracted, the optimum conditions for limonene Furthermore, the effect of CO2 flow rate and particle size of orange peel was studied in the range Do you want to read the rest of this article? of particle size and the effect of mass flow of CO 2 on the extraction rate of essential oil. This Dissertation is brought to you for free and open access by DigitalCommons @URI. properties of supercritical C02 are summarized in Table 2. 4. to an uniform condition within the nucleating medium, and hence in principle to narrow . Table The density of carbon dioxide from the Bender equation and .. Supercritical CO2 is the most commonly used solvent in extraction processes, .. make use of the RESS process to reduce the particle size and narrow the.