It is considered one of the most ancient cultivated plants and due to its long history of cultivation, it is difficult to identify its exact centre of origin. According to phylogenetic studies based on molecular analysis and studies on sequence homology of ancient and modern DNA extracted from archaeobotanical and modern samples, respectively, most researchers agreed that this plant species originated in central Asia and was introduced in Europe as a cultivated and domesticated agricultural plant during the Bronze age (approximately, from the 22th until 16th century BC)   . Nevertheless, a recent work by McPartland and colleagues  provided evidence that C. sativa was indigenous also to Europe. Currently, there are no more traces of wild-type hemp and only domesticated (i.e., individuals of a species chosen and selected by humans for characteristics making them useful to people) and ruderal (i.e., forms growing outside of cultivation) hemp plants exist. Independently to its origin, the nowadays-domesticated form of C. sativa L. is widespread and cultivated not only in the Asian countries, but also in Canada, the United States (US), Europe, and Africa. It is a multipurpose, sustainable, and low environmental impact crop which can be useful for several application fields, from the agricultural and phytoremediation to food and feed, cosmetic, building, and pharmaceutical industries. Indeed, from this highly versatile plant, it is possible to obtain various products of industrial interest such as fibre and shives; bio-building and thermal insulated materials; seeds, flour and oil with important nutritional and functional features; and bioactive compounds of pharmacological interest  (Figure 1).
Several works clarified well the cannabinoids’ biosynthetic pathway       . According to these studies, a common precursor of all the main cannabinoids exists, and it is the cannabigerolic acid (CBGA). In the cytosol, CBGA is converted into the acidic form of the three main cannabinoids, from which other related cannabinoid compounds will originate, namely tetrahydrocannabinol acid (THCA), that in the acidic form has no psychoactive activity; cannabidiolic acid (CBDA); and cannabichromenic acid (CBCA). This conversion is catalysed by an oxidocyclase specific for each cannabinoid (THCA-synthase, CBDA-synthase, and CBCA-synthase, respectively) (Figure 2). Finally, the acidic form of each cannabinoid undergoes non-enzymatic decarboxylation to their neutral and active form, i.e., THC with psychoactive activity, CBD, and CBC that is found at high levels in juvenile plants   , respectively.
Nowadays the EU is the world’s largest hemp-producing market second only to Canada, with France, the Netherlands, Lithuania, and Romania as the major production centres  . According to the EU guidelines, also in Italy, the cultivation of industrial hemp has been recently restored through the law n. 242/2016, and the subsequent circular of the Ministry of Agricultural, Food and Forestry Policies (MIPAAF) published on 14 January 2017 that has delineated the conditions for hemp production, its commercialization, and its utilization for specific industrial purposes  .
The major discriminant factor related to the different intended uses of C. sativa L. is the level of the two major and more known phytochemicals characteristic of this crop, namely the only one psychoactive and toxicant compound of the plant, THC, and the non-psychoactive cannabidiol (CBD). Both of them belong to the cannabinoids’ class which includes over of 100 secondary metabolites belonging to the family of terpenophenolic compounds, typical of all C. sativa L. plants. These compounds are synthesized, collected, and stored in stalked glandular trichomes, that are specialized tiny secretory epidermal glands   , which are essentially present and abundant on the inflorescence of the female plant, whilst are present in lower numbers on leaves and stems, and are absent on roots and seeds, therefore, these latter organs do not contain cannabinoids    . A possible presence of cannabinoids in hempseeds could occur during the harvesting process, as a result of physical contact with the resin secreted by the glandular trichomes located on the bracts that surround the seed   . Hence, the presence of cannabinoids in hempseed actually represents a contamination, and the level of this contamination depends on both the cultivar ( cv ) and the cleaning process of the seed. Reasonably, THC contamination in seeds from C. sativa L. varieties which produce a low-THC level—as the industrial hemp varieties—should be extremely low  ; anyway, the adoption of a method for the quantification of the possible cannabinoid’s contamination and the level in hempseed products and food may be appropriate    .
Hemp (Cannabis sativa L.) is an ancient, widespread, multipurpose crop cultivated all over the world, all parts of which can be potentially usable for the production of many different commodities with industrial interest. It is one of the oldest cultivated crops and until the first half of the 1900s, it was widely grown essentially as a fibre crop. Declining the demand for natural fibre consequential to the upper hand of synthetic fibre, and competition from other plant fibre sources led to reduce the demand for hemp. In addition, the use of some narcotic strains containing high and unhealthy level (>0.3%) of the only one psychoactive substance, namely the cannabinoid delta-9 tetrahydrocannabinol (THC), led to the crop’s prohibition during much of the 20th century. The clarification of the genetics and the biosynthetic pathway of the cannabinoids has been essential to identify three main different genotypes and the related chemical phenotypes of hemp plants, differing in the content of the two main hemp cannabinoids, THC and cannabidiol (CBD). Among these, the chemical phenotype commonly named “industrial hemp” includes hemp varieties which contain <0.3% or 0.2% of THC level that makes them unsuitable for narcotic purposes, but very useful for many other industrial applications. Therefore, from a legislative point of view, the main western countries such as United States, Canada, and European Union after a prohibition period, from the last decade of 1900s, have reintroduced and restored the industrial hemp cultivation.
What is hemp?
Hemp is a variety of Cannabis sativa L. Hemp is a dioecious plant, which means that it can be separated into male and female plants. In hemp fields, there is usually a concentration of female hemp and sporadic placed males to pollinate the females and produce nutrient-rich seeds. Hemp has been used for over 10,000 years to make paper and fibres for clothing and fabric, but also in cosmetic products, particularly as an oil but also as other extracts and derivatives.
Other raw materials from hemp include by-products from production of hemp seed oil such as Cannabis Sativa Seedcake powder and Cannabis Sativa Seedcake, which may be used as abrasives, as well as derivatives such as Potassium Hempseedate, which can be found in soaps and handwashes, and Ethyl Cannabis Seedate, which may be used as a naturally derived Cyclopentasiloxane (D5) substitute.
Transparency and traceability
Following baseline regulatory compliance, for the formulation and subsequent claims made about natural and organic cosmetics, transparency and traceability are key to ensure that any substance extracted or derived from hemp used in a product ensures certain verifiable qualities. When using raw materials from Cannabis in cosmetics, brands should choose reliable supply chains that give proof of the traceability of these plant extracts from crop-to-shop. This is a key aspect for regulatory compliance but also for end consumers because it reassures them about the origin and qualities of these substances when used in a cosmetic product.
Marijuana and CBD are not the same even if they both come from the same plant. CBD is a single, isolated compound in the cannabis plant, while marijuana contains many naturally occurring compounds, including THC and CBD. Hemp seed oil, extracted from the seeds of Cannabis sativa L., Cannabaceae, has next to no THC or CBD.
Specific European and national legislation as well as international conventions apply to establish which type of extracts and derivates of the Cannabis sativa L. plant may be used in products, including food and cosmetics. Keep reading to find out more about hemp, an incresingly popular ingredient in cosmetics, and the differences in the extracts and derivates of the Cannabis sativa L. plant.
Fifteen hemp cultivars were grown and 13 cannabinoids were determined.
All cultivars corresponded to < 0.2 % limit of total tetrahydrocannabinol.
Bracts from upper and lower inflorescence contains similar cannabinoids content.
Big differences in cannabinoid content between cultivars were found.
Tetrahydrocannabinol/cannabidiol ratio > 1:30 was found in four cultivars.