Effect of gamma irradiation on phenol content, antioxidant activity and biological activity of black maca and red maca extracts (Lepidium meyenii walp)

Not All Maca Is Created Equal: A Review of Colors, Nutrition, Phytochemicals, and Clinical Uses

Maca (Lepidium meyenii, Lepidium peruvianum) is part of the Brassicaceae family and grows at high altitudes in the Peruvian Andes mountain range (3500-5000 m). Historically, it has been used as a nutrient-dense food and for its medicinal properties, primarily in enhancing energy and fertility. Scientific research has validated these traditional uses and other clinical applications by elucidating maca's mechanisms of action, nutrition, and phytochemical content. However, 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. Yet, research differentiating the colors of maca and clinical applications remains limited. In this review, research on the nutrition, phytochemicals, and various colors of maca, including black, red, yellow (predominant colors), purple, gray (lesser-known colors), and any combination of colors, including proprietary formulations, will be discussed based on available preclinical and clinical trials. The gaps, deficiencies, and conflicts in the studies will be detailed, along with quality, safety, and efficacy criteria, highlighting the need for future research to specify all these factors of the maca used in publications.

Effect of Black Maca Supplementation on Inflammatory Markers and Physical Fitness in Male Elite Athletes

Given the current lack of studies, the primary purpose of this study was to investigate the effects of black maca supplementation intake on changes in physical strength and inflammatory markers among elite athletes. Forty-four elite athletes were recruited for the present study. They included shooting athletes, racket sports athletes, and fin swimming athletes. The intake capsules contained 2500 mg of 100% concentrated black maca extract. Participants were instructed to take one capsule twice a day for eight weeks with pure water. Changes were seen in the ATP-PC systems and aerobic energy systems, particularly in the fin swimming athletes requiring aerobic energy systems. This effect is caused by increased antioxidant activity and influenced mitochondrial biosynthesis regulatory factors due to black maca supplementation intake. These findings provide preliminary evidence that elite athletes will benefit from taking black maca to improve their inflammation levels and physical fitness.

Effects of Maca on Muscle Hypertrophy in C2C12 Skeletal Muscle Cells

With aging, sarcopenia and the associated locomotor disorders, have become serious problems. The roots of maca contain active ingredients (triterpenes) that have a preventive effect on sarcopenia. However, the effect of maca on muscle hypertrophy has not yet been investigated. The aim of this study was to examine the effects and mechanism of maca on muscle hypertrophy by adding different concentrations of yellow maca (0.1 mg/mL and 0.2 mg/mL) to C2C12 skeletal muscle cell culture. Two days after differentiation, maca was added for two days of incubation. The muscle diameter, area, differentiation index, and multinucleation, were assessed by immunostaining, and the expression levels of the proteins related to muscle protein synthesis/degradation were examined by Western blotting. Compared with the control group, the muscle diameter and area of the myotubes in the maca groups were significantly increased, and the cell differentiation index and multinucleation were significantly higher in the maca groups. Phosphorylation of Akt and mTOR was elevated in the maca groups. Maca also promoted the phosphorylation of AMPK. These results suggest that maca may promote muscle hypertrophy, differentiation, and maturation, potentially via the muscle hypertrophic signaling pathways such as Akt and mTOR, while exploring other pathways are needed.

Maca extracts regulate glucose and lipid metabolism in insulin-resistant HepG2 cells via the PI3K/AKT signalling pathway

This work focused on the separation of the active ingredients of maca (Lepidium meyenii Walpers) and evaluated the antioxidative capability of these components with effects on improving glucose and lipid metabolism in insulin-resistant HepG2 cells. DPPH free radical scavenging and reducing power assays were used to evaluate the antioxidant activity of maca extracts. An insulin-resistant HepG2 cell model induced by glucose, fructose, oleic acid, and palmitic acid was adopted to investigate the effects of maca extracts on regulating glucose and lipid metabolism in this study. LC-MS/MS was then used for determination of the maca n-butanol (NBT) subfraction. The results showed that maca ethanol extract and subfractions of this extract exhibited certain antioxidant capacity. Furthermore, the NBT subfraction reversed the disorders in glucose and lipid metabolism in insulin-resistant HepG2 cells and significantly increased the mRNA expression of phosphoinositide 3-kinases (PI3K) and AKT in insulin-resistant HepG2 cells in a dose-dependent manner. In addition, the LC-MS/MS results showed that the NBT subfraction contained many active ingredients. Overall, this study suggests that the NBT subfraction of the ethanol extract rich in glucosinolates modulates insulin resistance via PI3K/AKT activation in insulin-resistant HepG2 cells and might exert potentially beneficial effects in improving or treating glucose and lipid metabolic disorders.

Maca extracts and estrogen replacement therapy in ovariectomized rats exposed at high altitude

PURPOSE

Hormone Replacement Therapy (HRT) and herbal remedies are often used to alleviate menopausal symptoms, but their effects and efficacy at high altitudes presents with several uncertainties. The purpose of this study was to evaluate whether pre-treatment with maca (Lepidium meyenii Walp) improved the tolerance to high altitude on an ovariectomized (OVX) rat model at sea level.

METHOD

The animals were treated with 17β-estradiol (200 µg/kg; E2), red and black maca (1.5 g/kg) for 28 days and exposed at high altitude or sea level.

RESULT

Our findings showed that red and black maca extracts significantly (P < .001) reduced the MDA level in OVX rat serum under hypoxia in a similar way to E2. Red and black maca extracts had similar effects with E2, by significantly (P < .001) reversing and increasing the ovariectomized induced decrease in cornified endometrial cell number. Under hypoxic conditions, the black maca (P < .05) and E2 (P < .01) increased the uterine weight in OVX rats. Finally, E2 alone significantly recovered the frequency of the uterine contractile response.

CONCLUSION

Aqueous extract of L. meyenii partially protects the reproductive function in hypobaric hypoxic environment, through the recovery of the cornified endometrial cells and uterine weight in a menopausal model of OVX rats.

Impact of gamma radiation on antioxidant activity in faba bean (Vicia faba L.) and the potential of meatballs formulation with inclusion of the powder of irradiated beans

In the present study, the effect of gamma radiation on antioxidant activity in faba beans was investigated. Whole seeds were irradiated at doses of 0-10 kGy and the antioxidant activity in samples was assessed by measuring the DPPH radical scavenging activity and ferric reducing antioxidant power in the ethanolic extracts of seeds. Exposing of faba bean seeds to ascending doses of gamma irradiation induced significant gradual increases in the antioxidant activity in faba bean and the maximum increases were observed in samples irradiated at dose of 9 kGy. Therefore, the potential of meatballs formulation with inclusion of the powder of 9 kGy irradiated faba beans was investigated with evaluating the antioxidant capacity and oxidative stability in non-irradiated and 4.5 kGy irradiated meatballs. Meatballs formulated with 20% of faba bean powder were highly acceptable. Neither incorporation of irradiated faba bean in meatballs formulation nor irradiation treatments of the prepared meatballs could adversely affect the acceptability of samples. Incorporation of irradiated faba bean, especially at 9 kGy, in meatballs formulation improved the antioxidant activity and oxidative stability in non-irradiated and irradiated samples and increased their refrigerated shelf-life through delaying of the appearance of mold growth on samples. Therefore, healthier meat products with enhanced oxidative stability can be successfully formulated with inclusion of irradiated faba beans.

Chemical composition and health effects of maca (Lepidium meyenii)

Maca (Lepidium meyenii Walpers) has emerged as a popular functional plant food due to various claimed health effects. This review details the major (i.e., starch, dietary fiber, and protein) and minor constituents (i.e., minerals, non-starch polysaccharides, polyphenols (flavonolignans), macaenes, macamides, glucosinolates, and alkaloids) of maca (root and aerial parts). Diverse health effects of maca are also summarized. Various bioactivities of maca include enhanced reproductive health, antifatigue, antioxidation, neuroprotection, antimicrobial activity, anticancer, hepatoprotection, immunomodulation, and improving skin health and digestive system's function. Plant genetics, botanical parts, processing, extraction, and experimental protocols represent the major factors affecting the chemical composition, physicochemical attributes, and health effects of maca-based products. However, clinical studies to support the claimed health effects of maca and related mechanisms appear to be lacking. Product innovation and diversification in food and non-food utilization of different parts of maca to maximize the value perceptions are suggested.

Ultraviolet light assisted extraction of flavonoids and allantoin from aqueous and alcoholic extracts of Symphytum officinale

Aim:

Symphytum officinale (comfrey) is a medicinal plant commonly used in decoction and to treat ailments. It protects the skin against ultraviolet (UV)-irradiation. UV irradiation may induce variable effects on the constituents of herbal extracts and thereby may limit or improve the advantages of using these extracts as medicinal supplements. This study aimed to assess the effect of UV radiations including UV-A, UV-B, and UV-C on the constituents of S. officinale aqueous and alcoholic extracts.

Materials and Methods:

Comfrey extracts (1% w/v) were prepared using distilled water, ethanol, and methanol. They were exposed to wavelengths of UV-A, UV-B, and UV-C for 10 min. The principal peak on the UV-spectroscopy scanning, the flavonoids, reducing power, and the allantoin levels were determined before and after irradiation.

Results:

UV irradiation reduces the magnitude of the principle peak at 355 nm wavelength of the aqueous infusion and methanol extracts. It improves the levels of flavonoids and reducing power of the aqueous extracts and increases the levels of allanotoin in aqueous and methanol extracts.

Conclusions:

UV-radiation enhances the yields of active ingredient of comfrey extracted with methanol, whereas improves the flavonoids, reducing power, and allantoin levels of comfrey extracted by the aqueous infusion method. UV-radiation reduces the levels of flavonoids, reducing power and allantoin when the comfrey extracted by alcohols.