Study On The Chemical Compositions In Alien Species Of Maca (Lepidium Meyenii Walp.)

The Maca (Lepidium meyennii Walp.) plant has highly nutritious and economic value asa food and medicine crop in the highlands of Peru. A lot of clinical studies permit that macahas different biological activities, such as fertility enhancer, aphrodisiac, adaptogen, anabolicand influence hormonal balance. At present, its reaserch work is mainly on secondarycompounds like alkaloids, glucosinolates, isothiocyanates, macamides and steroids. However,the corresponding relation between the active material basis and functional mechanism is stillquite indistinct, for the quantity and distribution of maca are very limited.Our country started to plant maca since the end of last century in Yunnan. Until now ithas been planted in Lijiang, Shangri-La, Huize, and got much progress in planting technology,yet the system studies on the distinction of nutritious in Maca from Yunnan and original isrear. It made an impact on the utilization of maca. Therefore it is of great significance toassess the quality change after introduction to Yunnan by testing its main nutritious andinorganic elements. The aim of this research is to discover the quality differences of macaafter the plant introduction to Yunnan, and to study the chromium speciation in simulatedgastric solutions, so that to lay a theoretical foundation for the utilization of maca and drugdesign.The contents of main nutritious components in Maca (Lepidium meyennii Walp.) rootsfrom different planting sources were determined. The results showed that the protein contentsin all maca roots are higher and significant differences, whereas no difference was observedin fat, carbohydrate, starch, amino acids, fiber and aliphatic acids, the contents of essentialamino acids in maca roots are no difference among three sources from Yunnan, yetsignificant difference comparing to Peru. Except for VD and VB6different sources havesignificant differences in other vitamins contents in maca roots.It made a study by ICP-MS method to determinate sixteen elements contents in macaroots from four habitats. The results showed that the higher content of Zn was found and nosignificant differences in maca roots from four habitats, yet the other fifteen elementscontents were significant differences. The highest content of B element was found in Perumaca root. In Shangri-La maca root we found the highest content of Mn. The highest contents of Sn and Ni were both found in Huize maca root. All the contents of Pb, Hg, Cd, As, Cuwere lower and conformed to the requirement. The correlations of nine pair elements reachedsignificant or highly significant level. Significant positive correlations were found for Co andAs, Hg and Sn, Ni, Sb, Cu (P<0.05). B and Sr, Sn, Sb had highly significant positivecorrelations (P<0.01).An LC-ICP-MS method is developed for Cr element morphometric analysis in macaroots. This method was extracted in simulation gastric solutions with the chelating agent ofethylene diamine tetraacetic acid (EDTA), and applied to determinate the contents of Cr(III)and Cr(VI) in maca roots from different sources. The results showed Cr is mainly present byCr(III) and the contents of Cr(III) and Cr(VI) were significantly different. That conformed tothe total contents.