Title
Bioactive Maca (Lepidium meyenii) alkamides are a result of traditional Andean postharvest drying practices
Date Issued
01 January 2015
Access level
open access
Resource Type
journal article
Publisher(s)
Elsevier Ltd
Abstract
Maca, Lepidium meyenii Walpers (Brassicaceae), is an annual herbaceous plant native to the high plateaus of the Peruvian central Andes. Its underground storage hypocotyls have been a traditional medicinal agent and dietary staple since pre-Columbian times. Reported properties include energizing and fertility-enhancing effects. Published reports have focused on the benzylalkamides (macamides) present in dry hypocotyls as one of the main bioactive components. Macamides are secondary amides formed by benzylamine and a fatty acid moiety, with varying hydrocarbon chain lengths and degree of unsaturation. Although it has been assumed that they are usually present in fresh undamaged tissues, analyses show them to be essentially absent from them. However, hypocotyls dried by traditional Andean postharvest practices or industrial oven drying contain up to 800 μg g1 dry wt (2.3 μmol g1 dry wt) of macamides. In this study, the generation of macamides and their putative precursors were studied during nine-week traditional drying trials at 4200 m altitude and in ovens under laboratory conditions. Freeze-thaw cycles in the open field during drying result in tissue maceration and release of free fatty acids from storage and membrane lipids up to levels of 1200 μg g1 dry wt (4.3 μmol g1 dry wt). Endogenous metabolism of the isothiocyanates generated from glucosinolate hydrolysis during drying results in maximal benzylamine values of 4300 μg g1 dry wt (40.2 μmol g1 dry wt). Pearson correlation coefficients of the accumulation profiles of benzylamine and free fatty acid to that of macamides showed good values of 0.898 and 0.934, respectively, suggesting that both provide sufficient substrate for amide synthesis during the drying process.
Start page
138
End page
148
Volume
116
Issue
1
Language
English
OCDE Knowledge area
Biotecnología agrícola, Biotecnología alimentaria Bioquímica, Biología molecular
Scopus EID
2-s2.0-84934889883
PubMed ID
Source
Phytochemistry
ISSN of the container
00319422
Sponsor(s)
The authors wish to acknowledge financial support from the Perú-Biodiverso program (account 318.1) and the Peruvian Ministry for Production FIDECOM-PIPEA program (contract 132-10). We also wish to thank Ecoandino S.A.C. and Carlos Arbizu and Iván Manrique from the International Potato Center (CIP) for providing plant and germplasm reference material. E.G.C. acknowledges travel support from the Alexander von Humboldt Foundation to visit the MPI-Jena. W.K. acknowledges support from the German Academic Exchange Service (DAAD) for a long-term professorship at PUCP. A.M. wishes to thank the DAAD for travel support for short term visits to PUCP.
Sources of information: Directorio de Producción Científica Scopus