Biomedical applications of hemp


  1. Germplasm collection of Cannabis sativa L.
  2. Development of hemp monoecious varieties
  3. Rapid screening tests for cannabinoids
  4. Breeding of specific Cannabis chemotypes for medical uses
  5. Purification methods to obtain Cannabis products for food and therapeutic purposes

Germplasm collection of Cannabis sativa L.

Some hundred accessions of Cannabis sativa L., with particular interest on monoecious genotypes, has been collected. The collection includes varieties and landraces endowed with useful traits like "Pinnatifidofilla", "Monofilla", high salt tolerance, Orobanche ramosa tolerance, corn bore tolerance and many chemotypes, including Cannabis sativa L. without any cannabinoids. Seed lots are stored in dehumidified room (30% R.U.) and low temperature (10°C). Smaller seed samples are conserved in sealed plastic-aluminium bags at -25°C.


Development of hemp monoecious varieties

Carmono: monoecious variety 2n. Derived from Carmagnola, cross with an Italian accession (Can-19) obtained from IPK-Gatersleben Genbank. The variety has similar yield and fibre production than traditional Italian dioecious Carmagnola. It has good tolerance to Orobanche ramosa and corn bore insect. It is a late maturing variety and should be useful for fibre and essential oil production. This variety was registered in 2000.

Codimono: monoecious variety 2n. It is obtained from a few monoecious plants derived from the old Superfibra variety. It is about 10 days earlier maturing than Carmono. It produces a good quality fibre for textile use and has higher fibre content (about 20%) than Carmagnola, but with a more elastic stalk. This variety was registered in 2000.

Ermes: monoecious variety 2n. Derived from one single Fibranova plant. It shows the "Pinnatifidofilla" sensum Crescini and Allavena leaf shape. The plant is the earliest Italian varieties and produce good seed yield. The leaf character is recessive trait that helps to maintain by visual selection pure variety. The leaf marker appear at the first true leaf stage showing a single leaf, while the normal varieties show tree composed leaf. This character help to maintain the variety not contaminated from hemp drug type or from dioecious or other monoecious variety. Continuous gas-cromatography analysis for THC evaluation is not needed because the visual control allows the elimination of the contaminating chemotypes. This variety is under registration.

Carma: monoecious variety 2n. It is derived from Carmono cross with a single "giganteum" plant selected from dioecious Carmagnola. It is 10% taller than Carmono and shows higher fibre content. Carma leaf is dark green and has a very vigorous stalk that could be higher than 4 meters in good soil conditions. This variety is under registration.



Rapid screening tests for cannabinoids

Laboratory tests: breeding need fast and simple methods to detect and to remove the hemp plant with high tetrahydrocannabinol (THC) content. Immunological, chromatographic and colorimetric tests could offer the right solution for every need. Immunological test used is at first competitive-ELISA, secondarily lateral flow immunoreaction.
Using both methods was started the breeding program to select hemp varieties with lower THC content than the EU limit allows (0,2%).
Gas-chromatography is used for selecting plants with very low THC content. It was realised a simple extraction method using a simplified analytical procedure. Colorimetric tests can be realised in field condition too. A simple test is currently used in our lab for the detection of drug type hemp without instruments and expensive reagents.


Breeding of specific Cannabis chemotypes for medical uses

Breeding lines producing single or few cannabinoids as principal constituent are selected. The lines are self-pollinated for more cycles using sex reversion technique of female plants. The procedure fix the chemotype and until now are available cannabidiol (CBD), tetrahydrocannabinol (THC), cannabigerol (CBG), and mixed chemotype of CBD and cannabidivirin (CBDV, a cannabinoid with pentyl chain instead the more common propyl chain).

Lines are under selection for increasing the poly-insaturated fatty acids and in particular gamma linolenic acid (GLA) fraction of seed oil. In such way, it can be produced some nutraceuticals preventing deficiency of essential fatty acid metabolism.


Purification methods to obtain Cannabis products for food and therapeutic purposes

Hemp produces many cannabinoids and others chemicals of pharmaceutical interest. The extraction and purification methods were optimised for obtaining partial pure cannabinoids or nutraceuticals. Organic extraction and chromatographic purification are currently in use to prepare concentrate solutions to be used in pharmacological tests. Seed oil, essential oil and cannabinoids are purified and used for further studies in pharmacology and diet studies in human and animal nutrition.