The Nutritional Composition of Maca in Hypocotyls (Lepidium meyeniiWalp.) Cultivated in Different Regions of China

Abstract

Maca (Lepidium meyeniiWalp.) was introduced to China in the recent two decades. Proximate compositions and secondary metabolites in dried maca tuber powders of different cultivation areas and colour types were analyzed and compared in order to provide the scientific guideline for its application. Cultivation region significantly affects the compositions of maca. The protein content of maca ranged from 9.31% to 21.02% by dry basis of maca powders and Xiaopingba-Y, Yulong-Y, and Pamirs-Y have the higher protein contents. The essential amino acids (EAA) contents ranged from 189.19 to 312.90 mg/g protein. The crude lipid content of different maca ranged from 0.59% to 1.00% and has no significant difference (P>0.05). The total dietary fiber (TDF) contents ranged from 17.82% to 26.00% and soluble dietary fiber (SDF) ranged from 2.46% to 7.88%, respectively. Maca samples were rich in Na, Mg, Ca, and K elements which ranged 138.3–187.8, 625.2–837.2, 3838.9–4502.7, and 5394.8–8063.3 mg/kg dry matter (DM). Xiaopingba-Y has the highest benzyl glucosinolate content which was 2.31 mg/g DM. Peru-Y and Xiaopingba have the higher contents of total alkaloids contents which was 2.61 and 2.56 mg/kg DM. Yongsheng-Y, Yulong-Y, and Pamirs-Y were rich in N-benzyl hexadecanamide contents, which were 0.164, 0.174, and 0.173 mg/g DM, respectively. Significant higher protein, total dietary fiber, insoluble dietary fiber, total alkaloids, and benzyl glucosinolate contents were found in purple and black maca compared to yellow maca in Pamirs, while there was no significant difference in N-benzyl hexadecanamide content.

Is the hype around the reproductive health claims of maca (Lepidium meyenii Walp.) justified?

“…Other studies have shown that the cultivation area can significantly affect the nutritional and metabolite content of maca. For example, yellow maca samples grown in China had a higher mineral and protein content than yellow maca grown in Peru (Zhang et al, 2015, Chen et al, 2017. Additionally, most scientific studies investigated the properties of Peruvian maca but not Chinese maca (see appendix 2).…”

Characterization of Maca (Lepidium meyenii/Lepidium peruvianum) Using a Mass Spectral Fingerprinting, Metabolomic Analysis, and Genetic Sequencing Approach

“…A recent study performed on maca cultivated in four different high-altitude areas of China and one from Peru showed that the content of benzyl glucosinolate (one of several glucosinolates) and N-benzyl hexadecanamide (one of several macamides) for all the plants of Chinese origin was significantly higher than from Junín, Peru. However, the total alkaloid level of the Peruvian sample was significantly higher than samples from three of the four Chinese locations [27].…”

Antioxidants in Maca (Lepidium meyenii) as a Supplement in Nutrition

“…Clement et al [8] reported that there are differences in Gls between ecotypes and the lead color ecotype of maca has higher total Gls than that of yellow, pink and violent. Supporting to this, black maca has more benzyl glucosinolate than yellow and purple macas [18]. But, other researchers found out that various ecotypes have Gls in similar quantities and there is not an influence of ecotype on Gls content in maca [20].…”

“…Czechia, the most of the N-benzylhexadecanamide is in that of China, then Peru and Czehia respectively. Further, macamide was not detected in maca grown in greenhouse [18,27,28]. However the above-mentioned studies argue that ecotype has no effect on macamide, they were reported that violent color of hypocotyl has higher total macamide than yellow, pink and lead colors of them [8].…”

“…The most of Gls in maca is aromatic type and glucotropaeolin. The Gls content varies by ecotype, part of maca plant, harvest time, cultivation region, drying and extraction process ( Table 2) [8,[16][17][18]. Also, researchers have focused on antioxidant and anticarcinogenic effects of Gls in maca [4,19].…”