Constituents of Cannabis sativa L. XIII: Stability of dosage form prepared by impregnating synthetic (--)-delta 9-trans-tetrahydrocannabinol on placebo Cannabis plant material.
Lewis GS, Turner CE
J Pharm Sci 1978 Jun;67(6):876-8
Abstract:
Synthetic (--)-delta 9-trans-tetrahydrocannabinol impregnated on placebo Cannabis decomposed only 6.3% after being stored for 1 year at --18 degrees. Storage at 5 degrees and room temperature under various conditions led to severe decomposition. The amount of cannabinol observed when (--)-delta 9-trans-tetrahydrocannabinol decomposed indicates that cannabinol is not the only decomposition product.
Stability of Cannabis sativa L. samples and their extracts, on prolonged storage in Delhi.
Narayanaswami K, Golani HC, Bami HL, Dau RD
Bull Narc 1978 Oct-Dec;30(4):57-69
Abstract:
The percentage rate of change into cannabinoids (Cannabidiol [CBD], tetrahydrocannabinol [THC] and cannabinol [CBN]) was higher in cannabis samples than in the extracts. This is probalby due to the decomposition of acids into corresponding neutral cannabinoids under the conditions of storage. Previous claims that CBD content in plant material is relatively constant are not substantiated by our results. There was a 1.0-2.5-fold increase in CBD content in plant material compared with the extracts. However, the fact that there was no appreciable increase in CBD/CBN content in the stored extracts of the same samples supports the view that the step-wise extraction does not bring the acids into the final extract pure delta 9THC decomposed at a rate of 41 per cent per year under tropical storage conditions. The delta 9THC content decreased in the samples and equally in the extracts though 100 per cent conversion of THC to CBN does not take place. The higher CBN content found in extracts than that expected by the conversion THC to CBN is a result of metabolic conversion.
The stability of cannabis and its preparations on storage
Fairbairn JW, Liebmann JA, Rowan MG
J Pharm Pharmacol 1976 Jan;28(1):1-7
Abstract:
Solutions of pure cannabinoids, nine samples of herbal and two of resin cannabis (one freshly prepared) were stored in varying conditions for up to 2 years. Exposure to light (not direct sunlight) was shown to be the greatest single factos in loss of cannabinoids especially in solutions, which should therefore be protected from light during analytical and phytochemical operations. Previous claims that solutions in ethanol were stable have not been substantiated. The effect of temperature, up to 20 degrees, was insignificant but air oxidation did lead to significant losses. These could be reduced if care was taken to minimize damage to the glands which act as "well filled, well closed containers". Loss of tetrahydrocannabinol after exposure to light does not lead to an increase in cannabinol, but air oxidation in the dark does. It is concluded that carefully prepared herbal or resin cannabis or extracts are reasonably stable for 1 to 2 years if stored in the dark at room temperature.
Stability of cannabinoids in dried samples of cannabis dating from around 1896-1905 Harvey DJ
J Ethnopharmacol 1990 Feb;28(1):117-28
Abstract:
Cannabinoids from three samples of cannabis obtained from the Pitt-Rivers Museum, Oxford, and dating from the turn of the century were examined by gas chromatography and mass spectometry for the presence of cannabinoids. Although the samples were from different geographical locations, the profiles of constituent cannabinoids were similar. In common with other aged material, most of the cannabinoid content was present as cannabinol (CBN), the main chemical degradation product of the major psychoactive constituent, delta-9-tetrahydrocannabinol (delta-9-THC). However, a substantial concentration of CBN acid-A was also present; this compound is unstable to heat and readily undergoes decarboxylation to CBN. Methyl and propyl homologues of CBN, together with delta-9-THC and its naturally occurring acid-A were also found at low concentrations in all samples. Intermediates in the formation of CBN from delta-9-THC, previously identified in aged solutions of the drug, were absent or present in only trace concentrations. However, oxidation products involving hydroxylation at the benzylic positions, C-11 and C-1', not seen in solution, were identified in substantial abundance. The results suggest that decomposition of cannabis samples may proceed more slowly than originally thought.
Preservation of cannabis
Turner CE, Hadley K
JAMA 1973 Feb 26;223(9):1043-4
No Abstract Available: I'm not sure this is actually on topic, find reference.
Microbiological contaminants of marijuana
McPartland JM, Journal of the International Hemp Association 1: 41-44.
Abstract:
Use of marijuana as a medicament is on the rise. Many medical marijuana users have a suppressed immune system, owing to their disease or treatment. Herbal marijuana, whether field grown or hydroponically cultivated, contains many microorganisms. Many of these organisms may pose a threat to immunosuppressed individuals. The microflora of marijuana is well described in the literature. Similarly, the microflora that cause opportunistic infections in AIDS patients is well documented. These separate literatures are correlated with commentary, and methods for detecting and eliminating microbial contaminants are discussed.
A collection of references on the degradation of cannabis and its active constituents and effects of different storage methods
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