Foreword From SG

We do not believe this study was broad enough to draw the conclusions it has. There were very few species used in the testing process, none of which are modern or select genetics. We do however supply this information to show how our government refuses to do proper studies. He holds One of only two DEA permits to grow Cannabis in the United States

Dr. Paul G. Mahlberg’s Cannabis Research

Interview can be found below

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NAIHC Board Member Dr. Paul G. Mahlberg is a Professor of Biology (plant biology) and Senior Fellow of the Institute of Molecular and Cellular Biology, Indiana University. He received his Ph.D. in Botany at the University of California, Berkeley and his MS and BS degrees in Botany at the University of Wisconsin, Madison. He has studied cannabis for over thirty years and has published over thirty articles on cannabis (Cannabis sativa), a tall annual dioecious plant group which includes both industrial hemp and marijuana. Wrote Laboratory Program in Plant Anatomy, and published two educational films. Served as a consulting editor to Academic Press in the preparation of ten monographs. Collaborated with Dr. Ivan Bocsa, Kompolt, Hungary, in a three-year USDA sponsored research study on hemp, and with Dr. Eun Soo Kim, Seoul, Korea, on organization and composition of glandular trichomes in cannabis and related plants. Served as a consultant to the United Nations Industrial Organization, Vienna, on industrial processing of raw opiates; to the University of Mississippi, School of Pharmacy, in its cannabis program; and to private companies in studies on secondary products of plants. Member of the board of directors of the Door County (Wisconsin) Land Trust which is dedicated to preservation of ecologically important land. One of only two federal DEA permits to grow cannabis in the United States is held by Dr. Mahlberg.  His research program began over thirty years ago and continues to the present, specializing in the ultra structure of the resin-producing gland and the biogenesis of its cannabinoids.  With his post-doctoral fellows and graduate students, he has explored these and other topics important to the definition of cannabis as either a drug or a fiber and food plant. Dr. Mahlberg’s most recent cannabis article, co-authored with his student Dr. Karl Hillig, is “A Chemotaxonomic Analysis of Cannabinoid Variation in Cannabis (Cannabaceae).” It was published in American Journal of Botany 91:966-975, 2004. A list of Dr. Mahlberg’s technical reports on cannabis appears below, with Internet links where available. His studies were directed to analyses of various cannabinoids and related secretory products, and their subcellular localization during plant development. As a teenager, Paul Mahlberg’s decision to become a botanist was stimulated by summers at Door County’s Kangaroo Lake in Wisconsin. Now retired from the biology faculty at Indiana University in Bloomington, he continues to do research on secretion by plant cells – and he has maintained his long-time connection with Door County. The latest example of this connection is that Dr. Mahlberg and his wife Marilyn Waite Mahlberg have co-authored Wildflowers of Door County, Wisconsin’s Unique Floral Preserve, “A field guide to the wildflowers that can be found in one of the most unique and beautiful places in America.” ———————————————— Cannabaceae Publications of Paul G. Mahlberg 39. Hillig, K. W., and P. G. Mahlberg. 2004. Chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae). Amer. Jour. Bot. 91: 966-975. Link to Abstract, full text available for a subscription fee. 38. Mahlberg, P. G., and E. S. Kim. 2003. Accumulation of cannabinoids in the secretory cavity of Cannabis. Jour. Industr. Hemp 9: 15-36. 37. Kim, E. S., and P. G. Mahlberg. 2003. Secretory vesicle formation in the secretory cavity of glandular trichomes of Cannabis (Cannabaceae). Mol. Cells 15: 387-395. Link to Abstract which includes link to free full text. 36. Mahlberg, P. G. 2003. Reintroduction of industrial hemp into American agriculture. Wisconsin Flora 4:3-6. 35. Kim, E. S., and P. G. Mahlberg. 2000. Early development of the secretory cavity of peltate glands in Humulus lupulus L. (Cannabaceae). Mol. Cells 10:487-492. 34. Kim, E. S., and P. G. Mahlberg. 1999. Immunochemical localization of tetrahydro cannabinol (THC) in chemically fixed glandular trichomes of Cannabis (Cannabaceae). Jour. Biol. Sci. 3: 215-219. 33. Hammond, C. T., and P. G. Mahlberg. 1999. Phloroglucinol as a natural phenolic constituent of Humulus lupulus (Cannabaceae). Amer. J. Bot. 87: 2105. 32. Kim, E. S., and P. G. Mahlberg. 1997. Cytochemical localization of cellulase activity associated with secretory cavity formation in glandular trichomes of Cannabis (Cannabaceae). Jour. Plant Biol. 40: 61-66. 31. Kim, E. S., and P. G. Mahlberg. 1997. Plastid development in glandular trichomes of Cannabis (Cannabaceae). Mol. Cells 7: 352-359. 30. Kim, E. S., and P. G. Mahlberg. 1997. Immunochemical localization of tetrahydrocannabinol (THC) in cryofixed glandular trichomes of Cannabis (Cannabaceae). Amer. J. Bot. 83: 336-342. Link to Abstract, full text available for a subscription fee. 29. Kim, E. S., and P. G. Mahlberg. 1995. Glandular cuticle formation in Cannabis (Cannabaceae). Amer. J. Bot. 82: 1207-1214. 28. Hammond, C.T., and P. G. Mahlberg. 1994. Phloroglucinol glucoside as a natural constituent of Cannabis sativa. Phytochemistry 37: 755-756. 27. Mahlberg, P. G., and E. S. Kim. 1992. Secretory vesicle formation in glandular trichomes of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 79:166-173. 26. Mahlberg, P. G., and E. S. Kim. 1991. Cuticle development on glandular trichomes of Cannabis L. (Cannabaceae). Amer. J. Bot. 78:1113-1122. 25. Kim, E. S., and P. G. Mahlberg. 1991. Secretory cavity development of glandular trichome of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 78:142-151. 24. Hammond, C. T., and P. G. Mahlberg. 1990. Thin-layer chromatographic identification of phenol in the glandular secretory system of Cannabis sativa L. (Cannabaceae). Ind. Acad. Sci. 98:201-209. 23. Turner, J., and P. G. Mahlberg. 1988. In vivo incorporation of labeled precursors into cannabinoids in seedlings of Cannabis sativa L. (Cannabaceae) pp. 263-270. In, G. Chesher, P. Consroe and R. Musty (eds.), Marihuana. Australian Gov’t. Publ. 22. Vogelmann, A., J. Turner, and P. G. Mahlberg. 1988. Cannabinoid composition in seedlings compared to adult plants of Cannabis sativa. J. Nat. Prod. 51:1075-1079. 21. Vogelmann, A., J. Turner, and P. G. Mahlberg. 1987. Cannabinoid occurrence in seedlings of Cannabis sativa L.: Quantitation in seedlings of known age and primary leaf length. Bot. Gaz. 148:468-477. 20. Turner, J., P. G. Mahlberg, V. Lanyon, and J. Pleszczynska. 1985. A temporal study of cannabinoid composition in continual clones of Cannabis sativa L. (Cannabaceae). Bot. Gaz. 146:32-38. 19. Vogelmann, A., J. Turner, and P. G. Mahlberg. 1984. Sequential appearance of cannabinoids during seedling development in Cannabis sativa L., pp. 18-23. In: Marihuana, D. Harvey (ed.). IRL Press, Oxford, UK. 18. Turner, J., and P. G. Mahlberg. 1984. Effects of sample treatment on chromatographic analysis of cannabinoids in Cannabis sativa L. (Cannabaceae). J. Chromatogr. 283:165-171. 17. Turner, J., and P. G. Mahlberg. 1984. Separation of acid and neutral cannabinoids in Cannabis sativa L. using HPLC, pp. 79-88. In: “Biology of Cannabinoids,” W. Dewey, S. Agurell, and R. Willette (eds.). Academic Press, N.Y. 16. Mahlberg, P. G., J. Turner, J. Hemphill, and C. Hammond. 1984. Ultrastructure, development and composition of glandular trichomes of Cannabis, pp. 23-51. In: Biology and Chemistry of Plant Trichomes, E. Rodriguez, P. Healey, and I. Mehta (eds.). Pergamon Press, New York. 15. Mahlberg, P. G., and J. Hemphill. 1983. The effect of light quality on cannabinoid composition of Cannabis sativa L. (Cannabaceae). Bot. Gaz. 144:43-48. 14. Turner, J. and P. G. Mahlberg. 1982. Simple high-performance liquid chromatographic method for separating acidic and neutral cannabinoids in Cannabis sativa L. Jour. Chromatogr. 253:295-303. 13. Turner, J., J. Hemphill, and P. G. Mahlberg. 1982. Interrelationships of glandular trichomes and cannabinoid content. II. Developing leaves of Cannabis sativa L. (Cannabaceae). Bull. on Narc. 33:63-71. 12. Furr, M. and P. G. Mahlberg. 1981. Histochemical analyses of unbranched non articulated laticifers and capitate glandular hairs in Cannabis sativa L. (Cannabaceae). Jour. Nat. Prod. 41:153-159. 11. Lanyon, V., J. Turner, and P. G. Mahlberg. 1981. Quantitative analysis of cannabinoids in the secretory product from capitate-stalked glands of Cannabis sativa L. (Cannabaceae). Bot. Gaz. 142:316-319. 10. Turner, J., J. Hemphill, and P. G. Mahlberg. 1981. Interrelationships of glandular trichomes and cannabinoid content. I: Developing pistillate bracts of Cannabis sativa L. (Cannabaceae). Bull. on Narc. 33:59-69. 9. Hemphill, J., J. Turner, and P. G. Mahlberg. 1980. Cannabinoid content of individual plant organs from different geographical strains of Cannabis sativa L. (Cannabaceae). Jour. Nat. Prod. 43:112-122. 8. Turner, J., J. Hemphill, and P. G. Mahlberg. 1980. Trichomes and cannabinoid content in developing leaves and bracts of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 67:1397 1406. 7. Hammond, C. and P. G. Mahlberg. 1978. Ultrastructural development of capitate glandular hairs of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 65:140-151. 6. Turner, J., J. Hemphill, and P. G. Mahlberg. 1978. Studies on growth and cannabinoid composition of callus derived of Cannabis sativa. Lloydia 41:453-462. 5. Turner, J., J. Hemphill, and P. G. Mahlberg. 1978. Quantitative determination of cannabinoids in individual glandular trichomes of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 65:1103-1106. 4. Turner, J., J. Hemphill, and P. G. Mahlberg. 1978. Cannabinoid composition and gland distribution in clones of Cannabis sativa L. Bull. on Narc. 30:55-65. 3. Hammond, C. and P. G. Mahlberg. 1977. Morphogenesis of capitate glandular hairs of Cannabis sativa L. (Cannabaceae). Amer. J. Bot. 64:1023-1031. 2. Turner, J., J. Hemphill, and P. G. Mahlberg. 1977. Gland distribution and cannabinoid content in clones of Cannabis sativa. Amer. J. Bot. 64:687-693. 1. Hammond, C. and P. G. Mahlberg. 1973. Morphology for glandular hairs of Cannabis sativa L. from scanning electron microscopy. Amer. J. Bot. 60:524-528.

Interview

Dr. Paul G. Mahlberg
American Cannabis researcher

One of only two DEA permits to grow Cannabis in the United States is held by Dr. Paul Mahlberg of the Biology Department at Indiana University, Bloomington.  His research program began over 20 years ago and continues to the present, specializing in the ultra structure of the resin-producing gland and the biogenesis of its cannabinoids.  With his post-doctoral fellows and graduate students, he has explored these and other topics important to the definition of Cannabis as either a drug or fiber plant.

 

Journal of the IHA:  How and when did you first become interested in Cannabis?

Paul Mahlberg:  My research interests focus on the secretion phenomenon in plants, with particular emphasis on the specialized laticifer cell, the secretory gland and secondary products in these structures. Cannabis is an excellent model for use in such studies because it possesses a great abundance of lipophilic glands as well as laticifers.  Cannabinoids represent interesting secondary products in this dioecious/monoecious plant because they occur only in this one genus.  Flower development, which is day-length dependent, can be induced even in a very young plant making it an excellent experimental subject.  These characters, which attracted my interests in about 1970, are desirable for our particular studies.

JIHA:  Your laboratory is one of only two in the United States with DEA permission to grow Cannabis.  When and for what purpose were you granted your first research permit?

PM:  I received my license to study Cannabis about 1970 for the purpose of cultivating the plant and studying its morphology and cannabinoid composition.

JIHA:  How many graduate students and post-doctoral fellows have studied Cannabis in your laboratory?

PM:  Six graduate students and 6 post doctorates or visiting faculty members have studied with me on the topic of Cannabis.

JIHA:  What research topics concerning Cannabis have you explored in your laboratory?

PM:  Our investigations have included several areas, in part, reflecting topics my students have chosen for their research.   Results from some of these studies are yet to be published.  One broad area includes studies on gland development and distribution, and formation of secretory content, including cannabinoids, at various phases of plant development.  This area includes our interests in gland evolution not only inCannabis, among its many strains, but in relation to glands among angiosperms.  We have been developing new concepts on gland development, and would like to examine them in relation to glands in other families.  Of course, we do wonder about cannabinoid evolution among the strains, as well.  It is curious as to why the pathway “ends” with THC (assuming CBN may be an artifact), yet evolved laterally, in a sense, with formation of propyl and other forms.  These two facets of evolution are still very much in need of study.
We have studied plant growth and cannabinoid composition and distribution in Cannabis clones to learn more about the interrelationships between genetically stable plants, and the role of selected environmental factors on cannabinoid production.  Included in this area have been our initial studies on the biosynthesis of these compounds.
The development of tissue-cultured materials to study cannabinoid synthesis attracted our attention, and still does, with the objective to manipulate the medium to control both cannabinoid formation and root-shoot formation.   While we are having some success with the latter, we must also concentrate on learning about factors that can stimulate cannabinoid formation.  Perhaps further study in this area can aid in identifying the gene controlling cannabinoid biosynthesis, with subsequent silencing of it in strains for economic utilization.

JIHA:  Which line of your research has yielded the most significant results in terms of our understanding of Cannabis?

PM:  Our most significant results derive from studies on the gland and the role of the gland in localization of cannabinoids.  The disc cells, and particularly the secretory cavity, of the gland perform a major role in the physiology of secondary products, activities yet to be understood.  This is so for glands not only in Cannabisbut other plants as well.  Whereas in other studies, individuals have directed attention to the secretory cells, they have ignored the secretory cavity – the very feature that characterizes the “gland”.  Thus, the data and concepts derived from our studies will reflect not only upon the glands of Cannabis, but perhaps will broaden our understanding of the nature of the secretory cavity in other glands.

JIHA:  What are you working on now and plan to explore in the future?

PM:  Several research topics or directions are being pursued at present and very briefly are presented here.  We employ several techniques in our studies including electrophoresis, chromatography, electron microscopy, morphology and tissue culture procedures.  While our studies represent basic research thrusts, they also have application to my interest in developing hemp as an agro-industrial crop.
Karl Hillig, a graduate student, is utilizing our germplasm collection of 200 strains to study the evolution and taxonomy of the genus.   He is using several techniques to accumulate data to interpret interrelationships between the strains which include, fiber, oil and drug-related forms.
Dr. Eun-Soo Kim and I are studying cannabinoid localization and secretion in glands using THC antibodies as probes to identify the organelle or membrane involved with THC synthesis, and the mechanism of secretion into the secretory cavity.  This study is a facet of our ongoing study on the mechanism of plant cell secretion.  Perhaps it will be possible to identify the gene(s) related to THC and other cannabinoid syntheses.
In our tissue culture studies, Dr. Tom Hammond and I are examining the role of different compounds in the synthesis of cannabinoids, and in shoot (plantlet) formation.  We wish to learn the mechanism of cannabinoid formation with the objective to control formation of these compounds.

JIHA:  If funded, what line of Cannabis research would you personally find the most interesting to pursue?

PM:  My current and future studies will interrelate basic research with applied aspects of the study of hemp for commercial utilization.  One aspect of the latter is the development of hemp as a sustainable source of fiber.  A particular application of the fiber is for the production of particleboard.  C&S Specialty Builder’s Supply, Inc., has utilized hemp stalks, grown in Canada, to produce particleboard equal or better than that from trees.  An important aspect of this particleboard program is that the particleboard industry need not retool to produce it.  A manufacturer can use hemp or tree fiber in any combination for production of the board.  Thus, hemp can be grown as an annual crop to provide a sustainable source of income to farmers and provide a source of fiber to supplement wood fiber for industrial utilization.  In the United States, we are unable to grow hemp at this time because of the law preventing cultivation of all forms of Cannabis.   In contrast, many western countries, including our neighbor Canada, permit cultivation of hemp.  There are other components obtainable from the plant – such as oil from seeds or pharmaceuticals, but the possibility of gaining legal approval to cultivate non-hemp Cannabis in the United States in the near future is less probable than for hemp fiber strains.
Our present and future research will include a number of thrusts with the aim of enabling us to distinguish hemp from marijuana.   These goals include: a) to alter hemp morphologically so that it appears unlike marijuana, b) to further reduce the already low THC content in hemp strains with the objective to reduce it to zero, c) to evaluate the taxonomic relationships of accessions in our germplasm collection using molecular procedures to review speciation in this genus, d) to identify the gene controlling THC synthesis with the objective to block or alter its activity, and e) to utilize tissue culture procedures to alter the THC gene or introduce genetic markers to distinguish hemp from marijuana.  These research directions have the objective to develop superior fiber strains free of THC so that they can become an acceptable agricultural crop to law enforcement authorities.

JIHA:  How is your laboratory funded?

PM:  Our support is very minimal.  The strictures against all forms of Cannabis does adversely influence funding from national agencies.  We are fortunate to have some research support from private sources, including HortaPharm B. V., Amsterdam, and C &S Specialty Builder’s Supply, Inc., Oregon, as well as from the Indiana University Faculty Research Support Office.   These sources do not provide money for salaries.  Fortunately, students and visiting faculty have provided their own salary support in conjunction with their dedication to research interests.  Thus, our studies are very much underfunded, which makes it very difficult to progress at a desirable research pace.  Yet even at this slow pace we have made progress in several.directions as indicated above.

JIHA:  How many different accessions of Cannabis have you grown, which general gene pools do they represent and what is the purpose of investigating such diversity?

PM:  We have accumulated approximately 200 accessions in our germplasm collection with the aid of import permits.  These accessions include historically important strains from Europe, Asia and other world-wide sources.  Mr. Hillig is utilizing all of these strains in his studies.

JIHA:  Various theoretical pathways for the biosynthesis of cannabinoids have been proposed by you and other researchers.  Do you have any new theories on the biosynthesis of cannabinoids?

PM:  The cannabinoid pathway is most interesting in that it is known to occur only in the genus, Cannabis.  This phenomenon suggests that the pathway, and this genus, are evolutionarily recent in origin, or that the precursor(s) are unique to this genus, or that yet another factor may relate to the origin of this pathway inCannabis.  The general interpretation that a terpene and a phenol condense to form cannabinoids (purportedly CBG being the first cannabinoid) contrasts with an earlier one describing cannabinoid derivation from fatty acids.  Chemical synthesis supports the first interpretation and, while both terpenes and phenols are individually common in plants, this condensation appears unique to Cannabis.   Since the terpenoid (or geranyl) component represents a precursor in various pathways in different plants, we have become particularly interested in the role of the phenol component.  In chemical synthesis of cannabinoids, olivetol (1,5-dihydroxypentylbenzene) is interpreted to serve as the phenolic precursor, yet olivetol is not detected in plant extracts.  While olivetol is detectable in GLC of samples, it is also known that certain cannabinoids decompose during GLC to yield small quantities of olivetol.
Recently, we have reported an abundance of glycosidic or free phloroglucinol (1,3,5-trihydroxybenzene) in the laticifer and gland, whereas no olivetol was detectable.  These and other data raise the question as to which phenol(s) is involved in the biological synthesis of cannabinoids.

JIHA:  The inability of police to readily distinguish between Cannabis grown for marijuana and industrial fiber hemp has interfered with efforts to establish the latter crop in many areas.  A 1991 FAO publication suggests that morphological markers could be introduced into hemp to aid in their easy identification.  Do you have any interest in developing these easily recognized, low THC varieties?

PM:  Because of my interest in the agro-industrial development of hemp, I am most interested in developing markers in fibers strains to enable law enforcement officials to distinguish between hemp and marijuana.  We have begun a pilot study in this direction to develop a morphological marker.  In addition to studies on the normal plant, tissue cultures (including somatic hybridization) could be utilized to modify or introduce traits into cells, stimulate callus formation and induce plantlets to subsequently develop a flowering clone for character analysis.  I consider the development of such morphological variants to be important both for short and long term success of the hemp industry, given the present social climate concerning ‘drug abuse’.
Hemp is a non-drug form of Cannabis, as we know.  It is necessary for us to assist law enforcement officials to recognize that hemp does differ from drug forms.

JIHA:  What do you feel will be Cannabis‘ greatest benefit to humanity?

PM:  We must view Cannabis as we do any other crop plant.  If it can be cultivated profitably by growers to provide products such as fiber, oil, seed or pharmaceuticals, we must scientifically, socially and economically consider its potential value for utilization.  We know that hemp, as a fiber source, can contribute industrial products for development of a major industry.
Unfortunately, restrictive laws in the United States at present prohibit the cultivation of hemp as a fiber crop, thereby making it impossible to evaluate the potential of hemp as an agro-industrial crop in this country.   A revision of the statutes in the United States is necessary, and timely, to permit the cultivation of hemp for its industrial development.