Maca Root (Lepidium meyenii)

Maca root (Lepidium meyenii), a cruciferous biennial plant native to the high Andes of Peru (2 500–4 500 m), is cultivated for its fleshy subterranean taproot, which has been used for centuries as a nutritional and medicinal food. Modern dietary supplements exploit the root’s dense profile of glucosinolates, polyphenols, and unique alkylamides (macamides) to support energy, hormonal balance, and metabolic function.

Maca is a complex plant matrix; its principal bioactives are:

• Alkylamides: (e.g., N‑(3‑hydroxy‑5‑methoxy‑phenyl)‑2‑methyl‑2‑butenamide) – C₁₁H₁₇NO₂, MW 191 g/mol; they contain a fatty‑acid‑derived amide backbone with a phenyl‑substituted side chain.
• Glucosinolates: (e.g., glucobrassicin) – C₁₂H₁₅NO₆S, MW 389 g/mol; characterized by a β‑D‑glucose–sulfonate conjugated to a 4‑hydroxy‑3‑methoxy‑phenyl group.
• Polyphenols: (quercetin, C₁₅H₁₀O₇, MW 302 g/mol) with multiple hydroxyl groups conferring antioxidant capacity.

The root’s proximate composition includes 12–18 % carbohydrate (primarily fructose), 5–8 % protein, and 2–3 % lipids (rich in fatty acids such as linoleic and oleic acids). The overall IUPAC name for the primary alkylamide is (2‑E‑1‑(3‑hydroxy‑5‑methoxyphenyl)‑2‑methylbut-1‑en-1‑yl)‑N‑phenyl‑acetamide, reflecting its unique amide‑linked phenyl structure.

Maca is cultivated almost exclusively in Peru’s high‑altitude regions (Junín, Pasco, and Huancayo provinces) where the thin, cool climate fosters high glucosinolate and alkylamide concentrations.

• Harvesting: Commercially, roots are harvested at 6–9 months, washed, sliced or ground, and dried at ≤45 °C to preserve heat‑labile compounds.
• Extraction: Standardized extracts are obtained via aqueous‑ethanol (70 %) extraction followed by spray‑drying; the final product is standardized to 5–10 % total alkylamides (often measured by HPLC).
• Quality Considerations:
  • Geographic traceability: Certified Peruvian origin and altitude (>3 500 m) are linked to higher phytochemical content.
  • Processing method: Low‑temperature drying and minimal exposure to light/oxygen preserve glucosinolates and polyphenols.
  • Third‑party testing: for heavy metals (Pb, Cd, As) and pesticide residues is essential, as soil contamination can occur in high-altitude mining regions.
• Product Selection: Choosing products with a “standardized to X % alkylamides” label and independent certifications (e.g., USDA Organic, GMP) ensures consistent potency and safety.