Location: Natural Products Utilization ResearchTitle: Microscopic and UPLC-UV-MS analyses of authentic and commercial yohimbe (Pausinystalia johimbe) bark samples Author
Submitted to: Journal of Natural Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/5/2012
Publication Date: 3/9/2012
Citation: Raman, V., Avula, B., Galal, A.M., Wang, Y., Khan, I. 2012. Microscopic and UPLC-UV-MS analyses of authentic and commercial yohimbe (Pausinystalia johimbe) bark samples. Journal of Natural Medicine. 249-252. Interpretive Summary: Twelve commercial raw materials of yohimbe were analyzed using microscopic and UPLC-UV-MS methods. The present work also provides a detailed anatomy of the stem-bark/powder samples of yohimbe, with light and scanning electron microscopy images, for proper identification and authentication. It was observed that three samples may be adulterated. Four other samples were found to contain various levels of impurities. Chemical analysis of the powdered samples was carried out using UPLC-UV-MS techniques. The presence of yohimbine was found to be in the range of 0.1-0.91% in various samples. Yohimbine was not detected in one sample.
Technical Abstract: Yohimbine is the major alkaloid found in the stem-bark of yohimbe, Pausinystalia johimbe (Rubiaceae), an evergreen tree native to Africa. A number of yohimbe products are sold in USA as dietary supplements. Hand-sections of the stem-bark were prepared and the anatomical features were studied by light microscopy and scanning electron microscopy. The present work was aimed at providing a detailed anatomical description of the yohimbe bark as well as analyzing the commercial samples to ascertain their quality.