Correlation of mescaline concentrations in Lophophora williamsii (Cactaceae) with rib numbers and diameter of crown (U.S.A.)
Lophophora williamsii, peyote, is a small cactus growing to approximately 10 cm in diameter with a flat to dome-shaped spineless crown with fissures or ribs that develop following the Fibonacci series and whose numbers indicate relative degree of maturing. In this study crown tissue of 30 wild-collected specimens was analyzed to determine whether there was a correlation between the concentration of the primary alkaloid mescaline in crown tissue with the average diameter of the crown. We also compared mescaline concentration in three groups of ten individuals: 5 ribs (juvenile stage), 8 ribs (intermediate), and 13 ribs (elder/mature stage), since these Fibonacci numbers are the most stable and long-lasting on L. williamsii. This was designed to test the hypothesis that there is a positive correlation between mescaline concentration and both diameter and rib number. Nine greenhouse-grown specimens were likewise analyzed to serve as a control group for the study. All 39 tissue samples were subjected to an alkaloid extraction procedure followed by an acid-base washing procedure. Mescaline was identified using liquid-chromatography and mass spectroscopy and then quantified using reverse-phase high-pressure liquid chromatography. The Pearson’s Chi-squared test showed no statistical correlation between increasing mescaline concentration and increasing rib numbers for field-collected samples and greenhouse?raised control samples. Field-collected samples: P-value of 0.392; greenhouse control samples: P-value of 0.313. Similarly, field and greenhouse samples showed no statistical correlation between mescaline concentration and average diameter of the crown. Field-collected samples: P-value of 0.251; greenhouse control samples: P-value of 0.229. This study contributes to the understanding of this vulnerable species and to approaches to its overall conservation and the preservation of Native American culture.