Geographic Distribution of Three Alkaloid Chemotypes of Croton lechleri

Abstract

Three known alkaloids, isoboldine (2), norisoboldine (1), and magnoflorine (8), have been isolated for the first time from Croton lechleri, a source of the wound healing latex "sangre de grado". An HPLC system was developed, and a large number of latex and leaf samples of C. lechleri from 22 sites in northern Peru and Ecuador were analyzed to gain an understanding of the natural variation in alkaloid content for the species. Up to six alkaloids were found to occur in the leaves including, in addition to those listed above, thaliporphine (3), glaucine (4), and taspine (9), whereas the latex contained only 9. Taspine (9) is the component that has been previously found to be responsible for the wound healing activity of C. lechleri latex, and its mean concentration throughout the range examined was found to be 9% of the latex by dry weight. In addition, three chemotypes are defined based on the alkaloid content of the leaves, and the geographic distribution of these chemotypes is discussed along with a quantitative analysis of the alkaloid content as a function of chemotype.

Molecular Cloning and Characterization of CYP80G2, a Cytochrome P450 That Catalyzes an Intramolecular C–C Phenol Coupling of (S)-Reticuline in Magnoflorine Biosynthesis, from Cultured Coptis japonica Cells

“…Because CYP80G2 catalyzed the C-C phenol-coupling reaction from reticuline to corytuberine, the proposed precursor of magnoflorine (17,18), this result suggested that CYP80G2 is involved in magnoflorine biosynthesis. Because the enzymological properties of CYP80G2 were not clear, further analysis was performed using recombinant CYP80G2.…”

“…Involvement of CYP80G2 in Magnoflorine BiosynthesisAlthough (S)-corytuberine, produced from (S)-reticuline by CYP80G2, has been proposed to be a precursor of magnoflorine (17,18), no experimental evidence has been provided, either in vivo or in vitro. Thus, we examined whether (S)-corytuberine could be converted to magnoflorine using heterologously expressed S-adenosyl-L-methionine:coclaurine N-methyltransferase (CNMT) of C. japonica (22).…”

“…In addition, we discuss the role of the unique amino acid residue in the helix I region of CYP80G2 in its C-C phenol-coupling reaction. We also discuss the involvement of CYP80G2 in magnoflorine bio- synthesis, because corytuberine has been proposed to be the precursor of magnoflorine (17,18), an aporphine-type alkaloid produced by cultured C. japonica cells.…”

Evolving Concepts Related to Achieving Benefit Sharing for Custodians of Traditional Knowledge

“…It is important to appreciate that what is considered as traditional knowledge is an ever-evolving process. Access to other information, introduction of plants not indigenous to a region, natural inventiveness, as well as changing disease patterns, can all impose modifications on use and preference (Elvin-Lewis 2006; Lewis et al 1991, Lewis et al 2004, Milanowski et al 2002. Thus, the acquisition of these types of data and estimations of perceived worth has to be placed into a temporal context as well.…”

“…Several species or chemotypes can be involved that also possess the same or similar active components and thus claims of origin would be difficult to achieve if these taxa are known to be pervasive. A noteworthy example is the use of the sap of the Amazonian tree Croton lechleri and related taxa for wound healing throughout western tropical South America (Milanowski et al 2002). Also, some plants have such a global distribution and are used for the same purpose that claims of specific ownership would be impossible to validate, such as the use of Maclura tinctoria (L.) Steudel for tooth extraction throughout the tropics of Madagascar, Africa, and South America (Kaufmann & Elvin-Lewis 1995), the cosmopolitan uses of either Catharanthus roseus (L.) G.Don f. in remedies for diabetes (Lewis & Elvin-Lewis 2003), or of Phyllanthus species for hepatitis (Elvin-Lewis 2006).…”