Maca and Una de Gato for heath and well being

MACA Lepidium meyenii

ANTONIO BIANCHI[1]

BLACPALMA 2(3):30-36 May 2003
Articulo recibido: 18 de Enero de 2003
Recibido en forma revisada: 19 de Febrero de 2003
Aceptado: 20 de Febrero de 2003

A MORE COMPLETE FOOD THAN ROYAL JELLY

“This plant grows in the harshest
and coldest areas of the sierra,
where no other plant for man’s
sustenance can be grown”
                        Father Bernabè Cobo 1653

Who has ever seen the puna? An enormous and infinite cold desert. No trees, no flowers, only small clumps of dried grasses. A blue cold that takes your breath away, some puddles of stagnant water, an inert silence. At night, when the temperature falls well below zero, the twinkling of the stars is transformed into a cascade of light “Puna brava, Puna dura”, say the Peruvians. A desert of absolute cold surrounded by snow-covered peaks, a few huts with stone walls and thatched roofs and a gelid cold that penetrates right into your bones. The sun is there, immobile and distant at the same time, indifferent and sluggish in an absence of heat. It is in this hostile and distant environment that the small potato of the Andes grows, the secret of the ancient Inca, the Maca. Scientists call it Lepidium meyenii: actually not all of them, but the majority now agree that this is the real scientific name.

HISTORY

Its cultivation was once very common in many parts of the Perù and Bolivia plateau: the area of Huancavelica, Ayacucho and the department of Puno still have place-names such as “Macapata”, “Macapampa” or “Macachacra” (1). Today it grows only in a few parts corresponding to the ecological regions of Suni y Puna, on the shores of Lake Chinchapoya, in the department of Junin and Pasco, at an altitude of between 3700 and 4450 metres above sea-level. In total, less than 50 hectares are devoted today to the cultivation of this foodstuff (2). How has such a drastic reduction in the area of cultivation come about?

From prehistoric remains it is now confirmed that the first inhabitants of the Peruvian plateau knew the Maca: between 4000 and 1200 BC an agriculture based on the domestication of the “papa shillinco” of the Maca and of the Oca” was born. But it was the birth of the Cusco and the Inca civilization that fully exploited this tuber The Inca soldiers were fed with rations of Maca to increase their strength and physical performances in extenuating marches and fierce combats. Some writers (3) have even gone so far as to hypothesize that the ascent of this civilization could in some way be related to a diet based on this foodstuff.

The reason for the impressive restriction of the area of growth of Maca is mainly due to the progressive depletion of the soils (4). Maca, a foodstuff that is very rich in nutrients, is believed to progressively exhaust the soil. Therefore a system of cultivation by rotation is necessary, with a period of fallow for the soils of 5-10 years, but even with this system, with the passing of the years, the number of areas that can be cultivated progressively decreases. After centuries, Maca only grows now in a relatively small area of the Perù and this is despite research by the Instituto Nacional de Investigacion Agraria y Agroindustrial (INIAA) which has repeatedly tried to extend these cultivations.(5).

BOTANY

The first description of the maca was the merit of Dr.G. Walpers in 1843 who used a specimen from the department of Puno and coined the term Lepidium meyenii Walp. This description remained unquestioned until 1989 when Gloria Chacon proposed the distinction between Lepidium meyenii and Lepidium peruvianum Chacon, stating that only the latter is the legitimate maca (6). The work of this author was based on a cultivated specimen from the city of Cerro de Pasco, department of Pasco. In fact, this distinction has not had any particular follow-up today and all Authors today speak exclusively of the Lepidium meyenii as the only maca existing in nature, considering the term Lepidium peruvianum a synonym. From the botanical point of view, the maca corresponds to:

DIVISION
CLASS
SUBCLASS
ORDER
FAMILY
GENUS
SPECIES
COMMON NAME ANGIOSPERMAE
DICOTYLEDONEAE
ARCHICHLAMYDEAE
PAPAVERALES
BRASSICACEAE
Lepidium
Lepidium meyenii
MACA
Reference (3)

The Brassicaceae family consists of over 2500 species and over 350 genera, including very important vegetables such as broccoli and cauliflower. The term Lepidium derives from the Greek “Lepidion”, which literally means “small scale”, the name given by Dioscorides to small fruit of this genus. This is a cosmopolitan genus which includes about 130 species in the world: in Peru alone there are 15 species (7).

The maca appears essentially in the vegetative phase as a small rosette of leaves, which becomes larger in the generative phase when it is made up of leaves and flowers, and by a root generally of a conical shape, which is its underground organ and which can reach a length of about 18 cm and a diameter of about 6.5 cm. The dimensions can in fact vary a great deal, with very small specimen
s which reach 1 cm. in length and 0.6 cm. in diameter. Medium sizes are generally around 5-6 cm long and 3-5 cm wide.

The latter are those generally most appreciated by the Indian populations. The larger ones on the other hand, are too rich in fibre and are considered of poor nutritional value and called “shugla”. The colour of the root varies from plant to plant, ranging from light yellow to dark red and even brown-black: there exists a vast native classification of the different species which are not necessarily in relation to their quality, as shown by modern chemical studies. From a recent study carried out on 758 plants from the department of Junin, the following 13 ecotypes were found:

Colour of the root Percentage of ecotypes
Yellow
Red-white
Scarlet red-white
White-red
Lead grey
Black
Red-yellow
White
White- scarlet red
Yellow-red
Light lead grey
Scarlet red-lead grey
Yellow-light lead grey 47.8%
16.5%
9.0%
6.3%
5.4%
4.2%
3.7%
2.2%
1.6%
1.3%
0.8%
0.7%
0.5%
Reference (3)

PHYTOCHEMISTRY

As far as the chemical composition of maca is concerned, we have to distinguish two major categories: the primary compounds (of a nutritional nature) and the secondary ones. Nutritional studies on the maca have obviously revealed a considerable difference in the content of macroinutrients. In 1968 Gloria Vasquez, in her doctoral thesis, reported for the first time the following composition (9):

Chemical composition Percentage
Humidity
Total nitrogen
Proteins
Lipids
Carbohydrates
Ashes
Calcium
Iron
Phosphorus
Calories 35.51 g%
1.71 g%
10.30 g%
26.10 g%
24.63 g%
3.46 g%
207.90 mg%
9.93 g%
328.10 mg%
384.00 Kcal
Reference (3)
This study reveals an optimum protein content and an appreciable content of calcium and iron, which make this foodstuff indicated in many states of deficiency. In 1973 another thesis (9) appeared which in part confirms and in part scales down the previous data, reporting the following:

Chemical composition Percentage
Major components
Water
Proteins
Lipids
Carbohydrates
Ashes
Calories 68.70%
3.80%
0.60 g%
23.00 g%
1.40 g%
176.00 kcal
Vitamins
Carotene
Thiamine
Riboflavin
Ascorbic acid 0.07 mg
0.15 mg
0.31 mg
3.10 mg
Minerals
Calcium
Phosphorus
Iron 94.00 mg %
57.00 mg %
2.20 mg %
Reference (3)

The results of this second study show a protein, lipid and iron content that is significantly less than the first and a calcium content that is still very appreciable. The difference in the results is probably to be derived from the different typology of specimens analysed. The larger potatoes, even if aesthetically better, are in fact rich mainly in fibre and therefore are of a low caloric and nutritional value, whilst the smaller ones have more macronutrients. A recent thesis at the University of San Marcos (10) has tried to put some order in the subject, focusing its interest on specimens that the farmers consider suitable for human consumption.

Major
compounds Yellow
variety
(g %) Red
variety
(g %) Black
variety
(g %)
Humidity
Total proteins
Fats
Fibres
Ashes
Carbohydrates
Total nitrogen
Non-protein nitrogen
Pure protein
(NP x 6.25)
Starch
Soluble sugars
Direct reducers
Soluble sugars
Indirect reducers 9.71
17.99
0.82
5.30
3.49
62.69
2.87
1.55
8.25

37.86
6.17

16.52 10.14
17.22
0.91
5.45
3.68
62.60
2.76
1.16
9.97

37.52
6.03

17.26
  10.47
16.31
0.82
4.95
3.63
63.82
2.42
1.36
7.7

38.18
7.02

17.10

Vitamins Yellow
variety
(mg %) Red
variety
(mg %) Black
variety
(mg %)
Niacin
Ascorbic acid
Riboflavin
Thiamine 43.30
3.52
0.61
0.42 37.27
3.01
0.50
0.52 39.06
2.05
0.76
0.43
Minerals Yellow
variety
(mg %) Red
variety
(mg %) Black
variety
(mg %)
Potassium
Sodium
Magnesium
Calcium
Phosphorus 1130
20
70
190
320 1160
20
80
200
290 1000
40
80
240
280
Trace elements Yellow
variety
(ppm) Red
variety
(ppm) Black
variety
(ppm)
Copper
Zinc
Manganese
Iron
Boron 6
32
22
80
12 6
30
20
62
24 8
30
22
86
26
Reference (3)

This last study, as well as confirming the concerns on the quality of the maca put on to the market, nevertheless reveals how maca has a very respectful protein content, especially if related with the low levels of fat. The fats of the maca are lower than that of the potato (1.8%), kiwicha (2.5%) or maize (3.9%). The presence of a discreet carbohydrate fraction nevertheless makes maca a foodstuff that, although reduced (comprised between 176 and 384 Kcal) is not without caloric value. This factor makes it an ideal complement in the athlete’s diet (rich supply of protein, few fats but with a discreet energy supply in terms of calories). This value is increased further if we analyse in particular the type of amino acids present in this Andean tubercle (11):

Amino acids Concentration
in mg/g
of protein
Glutamic acid
Arginine
Aspartic acid
Leucine
Valine
Glycine
Alanine
Phenylalanine
Lysine
Serine
Isoleucine
Threonine
Tyrosine
Methionine
HO-Proline
Histidine
Sarcosine
Proline
Cystine
Tryptophane 156.5
99.4
91.7
91.0
79.3
68.3
63.1
55.3
54.5
50.4
47.4
33.1
30.6
28.0
26.0
21.9
0.7
0.5
not determined
not determined
(essential amino acids in bold type),
Reference (3)

Practically all the essential amino acids, apart from tryptophane, are present. This data is also confirmed by subsequent studies (12):
Content in essential amino acids of the maca.

Amino acids G/100g
of
protein
Isoleucine
Leucine
Valine
Lysine
Phenylalanine + Tyrosine
Threonine
Methionine + cystine 4.3
6.8
6.3
5.8
4.8
4.5
3.3

The maca is therefore an ideal food for the athlete, precisely due to its richness in those nutrients essential for the development of a muscular mass that is adequate to sustain considerable and, above all, prolonged, effort. This obviously does not mean that we have in front of us the concentrations which certain “gym” supplements have made us used to, with great concern for safety and perplexity for their real effectiveness. The position of maca as a dietary supplement is more diversified and in a certain sense, more “complete”. It contains in the correct dietary concentrations, all the nourishment required by a person subjected to intense physical effort (such as a peasant obliged to work for 8 – 10 hours at over 4,000 metres above sea-level). In addition, the energizing action of the maca is not limited to its nutritional value. Experiments on rats have shown that taking maca in alimentary doses can increase the levels of glucose in hypoglycaemic rats after a prolonged fast (18hours) or after pharmacological induction (insulin): this data is particularly significant as it shows an action of glucogenesis, the production of glucose from the reserves of glycogen in the organism (13). The availability of glucose is put into relation with the energy reserves of the organism and the hypoglycaemic crisis is the first sign of the “collapse” of athletes subjected to prolonged effort. The utility of the maca for the athlete is therefore particularly indicated for those who are seeking an improvement in their physical resistance and in prolonged effort.

The concentration of relevant doses of minerals (11) make it more useful for this purpose.

Minerals mg/110 g
of dry plant
Iron
Manganese
Copper
Zinc
Sodium
Potassium
Calcium 16.6
0.8
5.9
3.8
18.7
2050.0
150.0

The presence of significant concentrations of iron and calcium also make it suitable to supplement all those situations of increased requirements, especially in women: pregnancy and ageing, above all. In particular the concomitant presence of high concentrations of these minerals and of all the essential amino acids necessary for the growth of the foetus make it an excellent source of nutrition during pregnancy, as reported by the Andean tradition knowledge. Naturally on condition that significant doses are reached, corresponding to about 5-10 g per day. On the other hand, its highly publicised use as a slimming supplement leaves us perplexed. Given its low but not negligible caloric value, the maca can represent an interesting foodstuff for slimming diets on condition that it is part of the daily calorie count: otherwise its use as an additional supplement risks altering the real calorie supply, compromising the result of the diet.

THERAPEUTIC ACTIVITY

As far as the secondary compounds currently identified in the maca are concerned, these are essentially of three categories:

-          COMPOUNDS OF A STEROID NATURE
These include the following compounds (11):

Steroid compounds Percentage
Sitosterol
Campesterol
Ergosterol
Brassicasterol
Ergostaniedol 45.50%
27.30%
13.60%
9.10%
4.50%

At the state of present knowledge and of the concentrations of these compounds present in the maca,. none of these components appear to be able to exercise a significant action on the properties of this foodstuff.

-          AROMATIC GLUCOSINOLATES
The maca contains isothiocyanates of an aromatic nature already shown in many other Brassicaceae. Between these glucotropaenoline and m-methoxyglucotropaeoline have been shown in particular (13). These compounds seem to have preventive activities on many models of tumours (especially of the gastrointestinal system) on experiment animals. It must however be specified that the concentration of these substances is much higher in foodstuffs closer to our dietary tradition (Brussels sprouts, broccoli etc.) therefore it appears decidedly illogical to use the maca to seek this chemical-preventive effect.

-          ALKALOIDS
Four alkaloids have been identified in the maca (3): macaine 1,2,3 and 4. The presence of these compounds has been put into relation with the aphrodisiac and anti-sterility activity of the maca but to date scientific proof is lacking in order to support this function.

-          POLYUNSATURATED FATTY ACIDS: THE PROBLEM OF THE ACTIVE INGREDIENTS.
The maca has, in traditional Andean medicine, an aphrodisiac and anti-sterility function. Altitude has in fact a strongly inhibiting action on sexuality and on the reproductive capacities of man and animals. The Andean peoples have always maintained that a diet based on the maca can contrast this effect. This action has been shown today in some experiments on farm animals. Regularly taking maca induces an increase in sexual relations and an increase in the Graaf follicles in the female animals, whilst in male animals the volume of seminal fluid is increased by 20%, sperm motility by 40% and the number of spermatozoids by 33%: all this can be translated in the end by a larger number of pregnancies brought to term (3). To reach these objectives the percentage of maca flour in the diet should correspond to about 6%. The limit of these studies mainly consists of the absence of a control group. This effect has subsequently been the object of at least four studies on animals (with a relative control group) which have at least confirmed the aphrodisiac effect. On the basis of this research it is probable that the active fraction is that regarding the polyunsaturated fatty acids; amongst these, two in particular take on particular importance, macaene and macamide (15). However, the presence of these compounds varies enormously in the various products on the market, oscillating between 0.15% and 0.84%, with the result that the consumption of these compounds oscillates between 1-52 and 14.88 mg/die (16). Other Authors had hypothesized in this sense a role of the isothiocyanates (1) or the steroid substances (11).

CLINICAL STUDIES AND EXPERIMENTAL PHARMACOLOGY

Two studies have been carried out in Italy, one in China and one in Perú. Two studies were carried out by the University of Modena. In the first, it was shown how the aphrodisiac effect, on experiment rats- visible through an increase in copulative performance, is independent of the nutritive value of the maca (17). In the second however, it was shown how above all the hexanic extract is responsible for this and not the chloroform extract (17). The Chinese study showed how by supplementing the diet of experiment rats with such an extract at 10% for 22 days there was, in the group treated, an increase in the number of sexual intromissions that was four times greater and an increase in the number of females positive with the presence of sperm of 2.5 times. (18). Whilst a Peruvian study showed that an aqueous extract of maca (66.7 mg/ml) given for 14 days results in an increase in the weight of the testicles and of the epididymis, with an increase in the number of mature spermatozoids (19).The last two studies essentially maintain how the use of maca has as a primary indication male sterility rather than a simple aphrodisiac effect and this action, from a therapeutic point of view, would without doubt be more fascinating and in tune with traditional Andean medicine. It must be underlined that a recent Peruvian study has shown how taking tablets of maca (1500-3000 mg/die) for four months led in nine subjects aged between 22 and 44 to an increase in seminal volume, in spermatozoid count and an increase of sperm motility and the number of mobile spermatozoids. None of these effects was in any way traceable to a hormone-mediated action due to an increase in luteinizing hormone, stimulating follicle, to an increase in prolactin, testosterone of estradiol (20). Given the worrying risks in the long term connected with an increase in these hormones, this is no meagre result.

The primary interest of maca for anti-sterility and possibly as an aphrodisiac (even if in this case we are still far from clear evidence) lies precisely in the fact that it seems to depend on compounds that contribute in some way to its food value. That is, it would be a question of natural substances with a wide safety margin (tests on animals have not shown any sign of toxicity at doses of 3 g/kg) which make maca a completely different aphrodisiac from substances such as ginseng, muira puana or yohimbina, for which (in the absence of equally clear evidence) there always exists the danger of side effects. Maca is a natural foodstuff that can be used for long periods and with an excellent margin of safety: the Andean peoples have been using it for thousands of years at high doses without any sign of toxicity having been shown.

PRODUCTION AND USES

As mentioned earlier, there exists a serious problem of availability of ground for maca: the Andean populations have consequently developed over the centuries a refined technology to maximise as far as possible the preservation of the beneficial properties of this foodstuff. The traditional method of preparation appears to consist of a slow drying of the fresh potatoes which takes from six to eight weeks. During the day the maca is spread out on special sacks and exposed to the sun of the Andes: it is gathered in the evening in order to protect it from the night freezing and exposed again the next day. Drying in the sun modifies the taste, making it more pleasant, perhaps degrading the fraction of glucosinolates or hydrolyzing the fibre content. At this point only the smaller potatoes are selected, as they are poor in fibre and richer in nutritive substances. The larger ones are kept as animal fodder. The pressure exercised by the commercial success in recent years of maca-based products today risks modifying this traditional system of production. There have been cases where the maca potatoes have been put on to the market without considering their dimensions and often dried quickly in rudimentary ovens. Even the Institute for the Study of Genetic Resources of the FAO in Rome intervened on the matter and which, in collaboration with the prestigious Centre for the Study of the Potato of Peru, set up a specific programme to protect the quality of maca put on to the market and to promote organic cultivation, free of chemical additives.

Today the advice for those who wish to use maca as an energizing foodstuff is without doubt that of using the flour or the whole potato: modern research has shown that this is the best way to preserve all the nutritive elements. Moreover, no research exists to date that has been able to isolate a fraction responsible for the energizing or anti-hypoglycemizing activity. The matter of the aphrodisiac properties is more complex: in this case, the experiments available would give more evidence for the use of extracts that exploit the presence of polyunsaturated fatty acids: different preparations, mainly in the form of capsules. are present on the European and American markets. Three thousand years on, the small potato from the Andes never ceases to amaze.

BIBLIOGRAPHY

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(2) Tello JM, Herman M and Calderon A (1992). La maca: cultivo alimenticio potencial para las zonas altoandinas. Boletín de Lima 14: 59-66.

(3) Obregon Vilches L (1998). Maca. Planta Medicinal y Nutritiva del Perú. Instituto de Fitoterapia Americano, Lima, Perú.

(4) Castro de León (1990). Un cultivo andino en extinción: el caso de la Maca. Perú Indígena, 12: 85-94.

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(8) Vásquez Baquerizo, G. (1968). Estudio químico-bromatológico del Lepidium meyenii. Tésis. Bachiller en Medicina. Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú.

(9) Alvarez Mayta T (1973). Estudio de la Maca y su valor nutritivo. Tésis. Faculdad de Ciencias de la Educación. Especialidad de Ciencias Químicas y Biológicas. Universidad Nacional del Centro del Perú (Huancayo).

(10) Yllessca Gutierrez MG (1994). Estudio Químico y Fitoquímico Comparativo de 3 Ecotipos de Lepidium meyenii. Cátedra de Bromatología, Faculdad de Farmacia y Bioquímica. Universidad Nacional Mayor de San Marcos, Lima, Perú.

(11) Dini A, Migliuolo G, Ratselli L, Saturnino P e Schettino O (1994). Chemical composition of Lepidium meyenii. Food Chemistry, 49: 347-349.

(12) Espinoza T and Poma I (1995). Determinación de aminoácidos esenciales de la Maca y elaboración de una mezcla proteica a base de alimentos andinos. Tesis. Facultad de Ingeniería en Industrias Alimentarias. Universidad Nacional del Centro del Perú, (Huancayo).

(13) Miura T, Hayashi M, Naito Y and Suzuki I (1999). Antihypoglycemic effect of Maca in fasted and insulin-induced hypoglycemic mice. J. Tradit. Med. 16: 93-96.

(14) Piacente S, Carbone V, Plaza A, Zampilli A and Pizza C (2002). Investigation of the Tuber Constituents of Maca (Lepidium meyenii). J. Agric. Food Chem. 50: 5621- 5625.

(15) Muhammad I, Zhao J, Dunbar DC, Khan IA (2002). Constituents of Lepidium meyenii ‘maca’. Phytochemistry 59: 105-110.

(16) Ganzera M, Zhano J, Muhammad I, Khan IA (2002). Chemical profiling and standardization of Lepidium meyenii (Maca) by reversed phase high performance liquid chromatography. Chem. Pharm. Bull. 50: 988-991.

(17) Cicero AFG, Bandieri E e Arletti (2001). J. Ethnopharmacol. 75: 225-229.

(18) Zheng BL, He K, Kim CH, Rogers L, Shao Y, Huang ZY, Lu Y, Yan SJ, Qien LC and Zheng QY (2000). Effect of a lipidic extract from Lepidium meyenii on sexual behavior in mice and rats. Urology 55: 598-602.

(19) Gonzales GF, Cordova A, Gonzales C, Chung A, Vega K and Villena A.(2001). Lepidium meyenii (Maca) improved semen parameters in adult men. Asian J. Androl. 3: 301-303.

(20) Gonzales GF, Ruiz A, Gonzalez C, Villegas L, Cordova A (2001). Effect of Lepidyum meyenii (maca) roots on spermatogenesis of male rats. Asian J. Androl. 3: 231-233.