macaenos

Macaenes: A Comprehensive Reference

1. Identity: Botanical Source, Chemical Nature, and Nomenclature

Macaenes are a class of bioactive natural compounds found exclusively, or in highest concentration, in the hypocotyl (root-like underground storage organ) of Lepidium meyenii Walpers, the plant commonly known as maca or Peruvian ginseng. Lepidium meyenii, known as maca or Peruvian ginseng, is an edible herbaceous biennial plant of the family Brassicaceae native to South America in the high Andes mountains of Peru and Bolivia. The species is also referred to in some phytochemical literature as Lepidium peruvianum Chacón, a name proposed following taxonomic work in the late 20th century, though L. meyenii remains the name most widely used in peer-reviewed research. Many scientific and commercial sources use the name Lepidium meyenii Walp.; other sources, especially those following Gloria Chacón de Popovici, use Lepidium peruvianum Chacón.

Chemically, macaenes belong to the broader category of polyunsaturated fatty acid derivatives. Some types of unique constituents in maca, such as macamides (benzylamides of long-chain fatty acids) and macaenes (unsaturated long-chain fatty acid derivatives), are responsible for its various bioactivities. The two simplest and most representative macaenes identified in maca are linolenic acid and linoleic acid. In diagrams of chemical structures of macamides and macaenes found in maca, macaenes ME 1 and ME 2 are identified as linolenic acid and linoleic acid, respectively. More complex macaene derivatives include oxidized and hydroxylated forms derived from these parent fatty acids. 9-Hydroperoxy-10E,12Z-octadecadienoic acid and 13-hydroperoxy-9Z,12E-octadecadienoic acid are synthesized by linoleic acid through catalysis by lipoxygenase enzymes; these hydroperoxy intermediates are then transferred into the basic skeleton of macaenes — specifically 9- or 13-hydroxy- and 9- or 13-oxo-octadecadienoic acids — through the action of glutathione peroxidase and hydroxy fatty acid dehydrogenase.

Macamides and macaenes are benzylated alkamides, which are natural compounds often used to identify maca accurately. Macamides are considered unique to maca, whereas macaenes can be found in other plants such as tomatoes and eggplants. This distinguishes macaenes from macamides, which have never been found in any other plant species.

Macamides and macaenes are assumed to be the characteristic marker compounds of maca as they have not been found in any other plants — at least not in meaningful concentrations — and are widely employed in analytical methods as phytochemical fingerprints for authentication of maca products. Based on the fact that macamides and macaenes are characteristic components in maca, their contents have been used as principal components to successfully differentiate maca from different origins using principal component analysis (PCA).

Macaenes and macamides are intimately related: macamide formation is based on the amidation reaction of macaenes and benzylamine. That is, macaenes serve as the fatty-acid precursor scaffold to which benzylamine (or substituted benzylamines) is added enzymically to form the amide bond characteristic of macamides. Both compound classes are therefore part of a biosynthetically interconnected network, and research on the two classes is frequently presented together. Secondary metabolites in maca have been categorized into several groups: glucosinolates, macamides, macaenes, alkaloids, sterols, and fatty acids.

1.1 Common Names and Synonyms

• Macaenes (the standard chemical term for the polyunsaturated fatty acid components of maca)
• Maca polyunsaturated fatty acids / maca PUFAs
• Benzylated alkamides (used collectively with macamides)
• Plant source common names: Maca, Peruvian ginseng, maca-maca, maino, ayak chichira, ayak willku (Quechua names)

1.2 Forms and Preparations

Macaenes as such are not produced in isolation as standalone commercial supplements; they are consumed as integral components of whole maca root preparations. Maca is grown for its fleshy hypocotyl fused with a taproot, which is typically dried but may also be freshly cooked as a root vegetable. As a cash crop, it is primarily exported as a powder that may be raw or processed further as a gelatinized starch or as an extract. If dried, it may be processed into a flour for baking or as a dietary supplement.

Maca is available commercially in several dosage forms including powder, liquid, tablets, and capsules. The macaene content of a given product is directly shaped by post-harvest processing. Significant variations of macamide content have been found in commercial maca products (ranging from 69 to 2738 µg/g). Analysis of the macamide biosynthetic pathway suggests that (a) glucosinolate catabolism, (b) lipid hydrolysis, and (c) amide formation are key steps controlling macamide accumulation in the tissues during the postharvest drying process. Since macaenes are precursors to macamides in this pathway, drying conditions that increase macamide formation correspondingly modulate macaene pools.

Powdered maca provided the largest macamide accumulation, followed by sliced hypocotyls, while whole roots displayed a significantly reduced amide-generating potential; the ideal temperature for macamide formation is about 30 °C; macamide content increases continuously along with storage time.

2. Traditional and Historical Use

Lepidium meyenii (maca) is a Peruvian plant of the Brassicaceae family cultivated for more than 2000 years, which grows exclusively in the central Andes between 4000 and 4500 m altitude. Its use as both a dietary staple and a medicinal plant predates the Inca empire. Lepidium meyenii Walp., a species of the family Brassicaceae, has been cultivated both as a crop and medicinal plant for 1300–2000 years in Peru.

Maca is an annual or biennial Andean crop, also known as maca in Peru, where it can be extensively grown at high altitudes (3500–4800 m). Its underground storage hypocotyls have been a traditional medicinal herb and dietary staple since pre-Columbian times. This ancient plant cultivated by natives since Inca times is a centuries-old South American medicinal herb restricted in distribution to high Andean plateaus above 4,000 m a.s.l., and has been traditionally used by indigenous Peruvians as a vital dietary supplement and an important staple food component in their diet.

Traditional preparations centered on the cooked or dried hypocotyl. The tuber of this Peruvian plant is traditionally eaten as a vegetable: boiled or fried, much less raw. For this, the tuber is dried naturally in the sun for four to six days. Many local food products (flour, drinks) incorporate maca. This includes a fresh fermented drink, very popular in Peru, called "chicha de maca," as well as distilled maca liquors. Natives from the highlands of Peru recommend that maca be boiled before its consumption because fresh maca may have adverse effects on health.

The traditional purposes attributed to maca encompassed both nutritional and medicinal domains. Traditional uses of maca report an improvement in endurance and strength, on the one hand, and sexual vigor and fertility in men, on the other. A document dating from the 13th century reveals that Inca warriors used to consume maca before each battle in order to increase their energy in battle. Historically, it has been used as a nutrient-dense food and for its medicinal properties, primarily in enhancing energy and fertility.

The botanical significance of the plant was formally recognized in the West when German botanist Gerhard Walpers named the species in 1843. Antonio Vázquez de Espinosa described the plant following his visit to Peru circa 1598, and Bernabé Cobo described this plant in the early 17th century. Gerhard Walpers named the species Lepidium meyenii in 1843. It was not until the early 1960s that maca and its historically unique properties started to be researched by Peruvian scientist Dr. Gloria Chacón Realdon, who is credited with the re-discovery of this long-forgotten plant and acknowledged as the first scientist pioneering in-depth research into this ancient medicinal plant of the Incas.

The traditional Andean postharvest drying ritual has particular scientific significance. Macamides have been found to be the result of traditional post-harvest drying practices, as proposed in their biosynthesis mechanism, which involves the enzymatic degradation of glucosinolates to amines, the hydrolysis of storage and membrane lipids, and the formation of amide bonds. This means that the bioactive macaene and macamide content of maca is itself a product of traditional processing methods, not simply the raw plant material.

3. Key Constituents and the Relationship of Macaenes to Other Maca Compounds

Maca root contains a diverse phytochemical matrix alongside macaenes. The underground root of this plant is rich in macamides, maca alkaloids, glucosinolates, volatile oils, sterols, polyphenols, and macaenes. The dry maca root contains 8.9–11.6% proteins, 1.1–2.2% lipids, 8.2–9.1% fiber, 5.0% ash, and 54.6–60% carbohydrates.

Within the secondary metabolite profile, reviews over the last two decades have indicated that glucosinolates, macamides, macaenes, and alkaloids are the main bioactive components of maca. More recently, a series of novel thiohydantoins which generally exhibit a variety of activities have been isolated from maca; this review focuses on their biosynthetic pathway, which indicates that macamides, thiohydantoins, and some alkaloids may originate from glucosinolates.

So far, more than 50 different compounds between fatty acids and macaenes have been identified in different studies on L. meyenii. The biosynthetic relationship between macaenes and macamides is central to understanding both compounds: macamides are synthesized via the reaction of benzylamine or its substitutes and long-chain fatty acids catalyzed by enzymes during the drying process; long-chain fatty acids are the precursors of macamides.

The macaene content of maca also varies by phenotype (color). Maca batches from different producers significantly vary in the amount of macaene, macamides, sterols, and glucosinolates. In 2005 appeared the first publication indicating that different maca color types have different properties, and more recently it has been found that maca colors associate with variations in concentrations of distinct bioactive metabolites. Research over the last twenty years has identified up to seventeen different colors (phenotypes) of maca. The color, hypocotyl size, growing location, cultivation, and post-harvest processing methods can have a significant effect on the nutrition content, phytochemical profile, and clinical application.

4. Mechanisms of Action

4.1 Precursor Role in Macamide Biosynthesis

The most clearly established mechanistic role of macaenes is as biochemical precursors to macamides. Macamides are inhibitors of endocannabinoid neurotransmitter degradation in mammalian nervous systems. They result from the condensation of benzylamine, a glucosinolate hydrolysis product, with free fatty acids released from lipid hydrolysis. In this pathway, macaenes (the oxidized and modified polyunsaturated fatty acid intermediates) are the immediate precursors. 9-Hydroperoxy intermediates are transferred into the basic macaene skeleton through glutathione peroxidase and hydroxy fatty acid dehydrogenase, generating the hydroxy- and oxo-octadecadienoic acid forms of macaenes.

4.2 Endocannabinoid System Modulation (via Macamides)

Because macaenes and macamides are studied as a functionally coupled pair — macaenes being the structural backbone from which macamides are formed — the neuropharmacological mechanisms ascribed to macamides are directly relevant to the macaene/macamide system as a whole. Macamides are a distinct class of secondary metabolites, benzylamides of long-chain fatty acids, isolated from the Peruvian plant Lepidium meyenii. As structural analogues of the endocannabinoid anandamide (AEA), they have demonstrated neuroprotective effects in vitro and in vivo.

Macamides play a stimulatory role on the central nervous system through inhibition of mammalian fatty acid amide hydrolase (FAAH) and the associated endocannabinoid receptor system. Macamides present in maca extracts are believed to be the active compounds responsible for the neuroprotective effect through inhibition of FAAH. FAAH inhibits anandamide endocannabinoid degradation, which is involved in cell proliferation of neural progenitor cells involving CB1 and CB2 receptors in this process.

Previous studies have demonstrated the activity of the pentane extract and its macamides, the most representative lipophilic constituents of maca, in the endocannabinoid system as FAAH inhibitors. One of the most active macamides, N-3-methoxybenzyl-linoleamide, was studied to determine its mechanism of interaction with FAAH and whether it has inhibitory activity on mono-acyl glycerol lipase (MAGL). Macamide concentrations from 1 to 100 µM were tested and showed no effect on MAGL. This suggests that the endocannabinoid modulation by macamides is selective for FAAH rather than extending to both major endocannabinoid-degrading enzymes.

It has been proposed that macamides may act on the nervous system through their inhibitory effect on the degradation of endocannabinoids by disrupting the activity of the FAAH enzyme. One study evaluated this property showing that the effect on FAAH was dependent on macamide concentrations and suggesting its probable irreversibility.

Macamide pre-treatment exerts significant neuroprotection against Mn-induced toxicity via a CB1 receptor-mediated mechanism. Macamides are potential ligands for nuclear receptor PPARγ.

4.3 Antioxidant Mechanisms

The antioxidant activity of maca crude extract (MCE), total macamides (TMM), and total macaenes (TME) was evaluated by DPPH radical scavenging, ABTS radical scavenging, and reducing power assays. The ability of MCE, TMM, and TME was tested against multiple cancer cell lines (leukemia HL-60, lung cancer A549, liver cancer SMMC-7721, breast cancer MCF-7, and colon cancer SW480). The results demonstrate that TMM has the best free radical scavenging ability and reducing power compared to MCE and TME; TME has the weakest antioxidant capacity among them. The difference in antioxidant properties between TMM and TME may be caused by benzylated alkamide in the chemical structure.

One key macamide (MAC 18:3, the linolenic acid-derived macamide) increases endogenous levels of the antioxidant glutathione (GSH) in the presence of MnCl₂ challenge. Regulation of sphingolipid metabolism and mitochondrial function were determined to be the main mechanisms underlying the neuroprotective effect of N-benzylhexadecanamide (a typical macamide).

4.4 Hormonal Considerations

A key mechanistic finding is that maca, including its macaene/macamide fraction, does not appear to exert its effects through direct sex hormone elevation. Gelatinized maca root at 1,500 or 3,000 mg/day over 4 months increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility in 9 healthy men aged 24 to 44 years. Serum hormone levels of luteinizing hormone, follicle-stimulating hormone, prolactin, testosterone, and estradiol were not modified with maca treatment. The proposed mechanism is instead neuromodulatory: macamides may influence the endocannabinoid system indirectly by resembling anandamide-like lipids, which could help explain perceived effects on mood, motivation, and sexual desire.

5. Scientific Evidence by Area of Use

Important framing note: The great majority of mechanistic data on macaenes and macamides derives from in vitro cell studies and animal models. Human clinical trials of maca generally tested whole-root preparations (powder, gelatinized powder, or extracts) in which macaenes and macamides are only two of many co-occurring bioactive constituents. No clinical trial has isolated macaenes as a pure compound and administered it to human subjects. The clinical evidence for maca as a whole is discussed below, with specific reference to the macaene/macamide fraction where the source material supports it.

5.1 Sexual Function and Libido

The potential bioactive ingredients in maca include macaridine, macamides, macaenes, glucosinolates, maca alkaloids, and maca nutrients. Macaenes and macamides have been reported as novel compounds in maca and are probably responsible for improving sexual behavior, although this needs to be further demonstrated.

Clinical studies, primarily focused on sexual health, indicate improved sexual desire, erectile function, and subjective wellbeing in men. Several small, placebo-controlled trials in adults report modest increases in self-rated sexual desire with maca after 6–12 weeks. Recent clinical trials have also suggested significant effects of maca for increasing sperm count and mobility and improving sexual function in humans.

Clinical trials showed efficacy of maca on sexual dysfunctions as well as increasing sperm count and motility. However, the systematic review literature provides important cautions: the available data are insufficient for determining whether maca is clinically effective based on the number and quality of trials reviewed. Study populations have been small, and most trials lasted 12 weeks or fewer.

5.2 Fertility and Reproductive Parameters

Maca has been used for centuries in the Andes for nutrition and to enhance fertility in humans and animals. Animal experiments have provided the strongest mechanistic support: animal experiments suggest that maca has spermatogenic and fertility-enhancing activities, which are likely due to the phytosterols or phytoestrogens present in the maca. Several in vivo studies have shown that maca may improve sexual behaviour and enhance androgen-like effects in rats.

In the human domain, gelatinized maca root at 1,500 or 3,000 mg/day over 4 months increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility in 9 healthy men (24 to 44 years of age). Serum hormone levels of luteinizing hormone, follicle-stimulating hormone, prolactin, testosterone, and estradiol were not modified with maca treatment. This is a small, uncontrolled study and its results should be interpreted cautiously. Based on recent pharmacological studies, macamides exhibit a variety of biological activities including fertility promotion through promoting Leydig cell proliferation and testosterone secretion — findings that are preclinical (cell or animal level) only.

5.3 Energy, Exercise Performance, and Anti-Fatigue

Maca contains secondary metabolites, including macamides, macaenes, polysaccharides, fatty acids, glucosinolates, alkaloids, and flavonols that contribute to its neuroprotective, anti-fatigue, antioxidant, antitumor, anti-inflammatory activity, sexual improvement, and fertility enhancement.

Macamides are the main active components of maca that inhibit acetylcholinesterase, exert anti-fatigue effects, and free radical scavenging activity; N-benzyl-hexadecanamide is the active maca ingredient considered responsible for the anti-fatigue effects. Animal model evidence: the anti-fatigue properties of N-benzyl-(9Z,12Z)-octadecadienamide were evaluated by a weight-loaded forced swimming test. Results indicated that this macamide supplementation increased the forelimb grip strength of mice and exercising time remaining on the Rota-rod test.

Maca also shows promise in alleviating menopausal symptoms in women and enhancing physical performance. Human clinical data on anti-fatigue effects attributed specifically to macaenes or macamides in isolation are not yet available in the published literature. The evidence base for this application remains at the level of animal experiments and in vitro studies.

5.4 Neuroprotection

The neuroprotective potential of macamides (as derived macaene products) is the most extensively mechanistically characterized area in the preclinical literature. Recent years have seen an increase in exploration of the therapeutic effects of various metabolites extracted from maca. Among the most important secondary metabolites are macamides, molecules derived from N-benzylamides of long-chain fatty acids. Macamides have been proposed as active drugs to treat some neurological disorders. Their excellent human tolerance and low toxicity along with neuroprotective, immune-enhancing, and antioxidant properties make them ideal for exploration as therapeutic agents.

Yang et al. investigated possible neuroprotective mechanisms of macamides on neonatal hypoxic–ischemic brain damage (HIBD). They used macamide B (N-benzyl-9Z,12Z-octadecadienamide) and explored its effect on autophagy and apoptosis induced by HIBD. Their results were remarkable, indicating that this macamide significantly reduced brain damage and improved neuronal recovery.

Macamides are very important secondary metabolites produced by Lepidium meyenii Walp, which possess multiple bioactivities, especially in the neuronal system. In a previous study, macamides exhibited excellent effects in the recovery of injured nerves after 1-methyl-4-phenylpyridinium (MPP⁺)-induced dopaminergic neuronal damage in zebrafish. Regulation of sphingolipid metabolism and mitochondrial function were determined to be the main mechanisms underlying the neuroprotective effect of N-benzylhexadecanamide in an MPP⁺-induced neurodegeneration cell model.

All neuroprotective findings are currently from in vitro or animal studies; no human clinical trials have evaluated macaenes or macamides as treatments for neurological disease.

5.5 Antioxidant Activity

Maca, including its bioactive components such as macamides, has demonstrated antioxidant effects; however, the effect size of maca on oxidative stress has not been qualitatively described and calculated at the time of recent systematic reviews. Macamides can scavenge free radicals, protect cells from oxidative stress, and play a key role in anti-fatigue.

Regarding macaenes specifically: there are no published reports on the antioxidant activity of macaenes prior to the 2021 study examining macamide and macaene fractions directly. That study found that total macaenes (TME) have the weakest antioxidant capacity compared to total macamides (TMM) and maca crude extract (MCE). This evidence is preclinical (in vitro assays only). Macamides have shown antioxidant activity as one of their best-known properties and great potential as therapeutic agents; however, studies investigating this activity in humans are limited.

5.6 Anticancer Activity (In Vitro)

The ability of total macamides (TMM) and total macaenes (TME) was tested against multiple cancer cell lines: leukemia HL-60, lung cancer A549, liver cancer SMMC-7721, breast cancer MCF-7, and colon cancer SW480. TMM showed a good inhibitory effect on the five cancer cell lines tested. These are in vitro findings only and no clinical evidence for anticancer effects of macaenes in humans exists. The well-known bioactivities of macamides and macaenes are described as antitumor and antioxidant in preclinical literature, but translational confirmation is absent.

5.7 Menopausal Symptoms

Clinical studies indicate improved sexual desire, erectile function, and subjective wellbeing in men, and maca also shows promise in alleviating menopausal symptoms in women and enhancing physical performance. Human clinical data in this area relate to maca whole extracts; the contribution of macaenes specifically has not been separated from that of other active constituents.

5.8 Bone Health / Anti-Osteoporosis

Experimental scientific evidence showed that maca has nutritional, energizer, and fertility-enhancer properties, and it acts on sexual dysfunctions, osteoporosis, benign prostatic hyperplasia, memory and learning, and protects skin against ultraviolet radiation. Based on recent pharmacological studies, macamides exhibit biological activities including anti-osteoporosis effects — demonstrated in preclinical studies only. Dedicated human trials are not yet published.

5.9 Overall Evidence Characterization

Maca is a plant with great potential as an adaptogen and appears to be promising as a nutraceutical in the prevention of several diseases. Scientific evidence has shown effects on sexual behavior, fertility, mood, memory, osteoporosis, metabolism, and the treatment of some tumor entities. However, the active principles behind each effect are still unknown. The specific contribution of macaenes, distinct from macamides and glucosinolates, to any of these effects has not been established in a controlled human study. There is a lack of in vivo and clinical research with more representative sample sizes and more consistent methodologies.

6. Body Systems and Health Areas Associated with Macaenes

Based on the available peer-reviewed evidence, the following body systems and health domains have been investigated in the context of maca's macaene/macamide constituents:

• Central nervous system: Neuroprotection (via FAAH inhibition and CB1 receptor pathway); anti-fatigue; mood modulation; memory support (preclinical evidence)
• Reproductive system: Male fertility (sperm parameters); sexual desire and function in both sexes; female menopausal symptom relief (human clinical evidence, limited)
• Endocrine system: Adaptogenic effects; no direct steroidogenic action confirmed in human studies
• Skeletal system: Anti-osteoporosis activity (preclinical only)
• Metabolic / antioxidant pathways: Free radical scavenging, oxidative stress reduction (in vitro and animal evidence)
• Oncology (experimental): In vitro antiproliferative effects on cancer cell lines

7. Dosage Forms and Dosages Reported in Studies

Maca is available commercially in several dosage forms including powder, liquid, tablets, and capsules. Most commercial websites recommend a daily dose of one dried maca extract 450 mg capsule three times daily taken orally with food.

The most commonly cited dosage range in published human research is 1,500–3,000 mg/day of maca root preparations. Specifically: gelatinized maca root at 1,500 or 3,000 mg/day over 4 months was used to assess effects on sperm parameters in 9 healthy men aged 24 to 44 years.

The Peruvian native population in the central Andes uses the hypocotyls after it has been naturally dried and in amounts greater than 20 g/day as a traditional dietary staple, illustrating that very large quantities are consumed as food without reported adverse effects in the traditional context.

Animal studies have used pulverized maca hypocotyls in doses of 15, 25, 75, and 100 mg/kg for assessment of sexual behavior at 1, 7, 15, and 21 days of treatment.

For macaenes as isolated compounds, no standardized human dosage exists; they have not been administered as purified isolates in human clinical trials. Content in commercial products varies substantially: significant variations of macamide content have been found in commercial products, ranging from 69 to 2738 µg/g.

Currently, maca dietary ingredients comprise a wide range of products including maca root powder, maca root gelatinized powder, and different types of maca root extracts purified to specific groups of bioactive compounds in maca (i.e., glucosinolates, macamides, or amino acids), the latter ones requiring further evaluation for possible risk to health.

8. Safety Considerations and Interactions

8.1 General Safety Profile

Maca is generally safe, with rare adverse effects, supported by preclinical studies revealing low toxicity and good human tolerance. Maca has been reported to have a low degree of acute oral toxicity in animals and low cellular toxicity in vitro. No adverse reactions were reported in an animal study with rats fed maca extract in doses up to 5 g/kg. Its long-time use as a food product suggests a low potential for toxicity.

Macamides are of natural origin, and it has been shown that their consumption does not present side effects.

8.2 Thyroid and Goitrogen Considerations

Maca contains glucosinolates, which are the biosynthetic precursors to macaenes and macamides. These same glucosinolates carry a relevant safety signal: patients with thyroid conditions should avoid maca because glucosinolates taken in excess and combined with a low-iodine diet can cause goiter. Like its relatives in the Brassicaceae family, maca contains glucosinolates — sulfur-rich compounds that can break down into substances known to interfere with iodine uptake in the thyroid gland. These are sometimes called goitrogens because, in large enough amounts, they can contribute to goiter or worsen existing thyroid dysfunction.

8.3 Hormone-Sensitive Conditions

Maca is not a phytoestrogen with high concentrations of isoflavones like soybean and red clover, but it has been proposed to have progestin-like activity due to increases in uterine weight seen in a study with ovariectomized mice. While it may not be a classical phytoestrogen, by nature of its potential ability to enhance endogenous estradiol and progesterone levels depending on the possible phenotypes used and the form it is in, its use would be contraindicated in those with a personal history of hormone-sensitive cancer.

8.4 Pregnancy and Lactation

Maca use should be avoided during pregnancy and lactation due to a lack of safety and efficacy data.

8.5 Product Quality and Variability

Maca batches from different producers significantly vary in the amount of macaenes, macamides, sterols, and glucosinolates. This variability means that the pharmacological activity of commercial preparations cannot be reliably predicted without analytical characterization. Factors during postharvest drying that may directly affect biosynthesis of macamides include drying temperature, the shape of the tuber, and the storage period, which are key factors for the accumulation of macamides. Because macaenes are direct precursors to macamides, these same variables affect macaene levels.

8.6 Drug Interactions

No drug interactions with maca are well documented. There is no evidence of adverse reactions with maca in the reviewed clinical literature. Given that macamides inhibit FAAH — an enzyme in the endocannabinoid system — macamides act on CB1 receptors for neuroprotective activity against Mn-induced mitochondrial depolarization and toxicity, and the inhibition of FAAH was regarded as another mechanism for the anti-inflammatory and neuroprotective effects of macamides. Theoretical interactions with cannabinoid-pathway medications or FAAH-targeting drugs exist based on mechanism but have not been studied clinically.

8.7 USP Regulatory Status

Currently, maca dietary ingredients comprise a wide range of ingredients including maca root powder, maca root gelatinized powder, and different types of maca root extracts purified to specific groups of bioactive compounds in maca (i.e., glucosinolates, macamides, or amino acids), the latter ones requiring further evaluation for possible risk to health. Individual USP-NF quality monographs for these articles, including specifications, testing, and accepting criteria for the identity, composition, purity, and limits of contaminants, are currently in development.

References

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