Muira Puama (Ptychopetalum olacoides)

muira puama bark

Muira Puama Summary

Muira puama is a large tree native to the Amazon rainforest. The bark of this tree is used to treat related conditions in the Amazon.

Muira puama contains chemicals that directly inhibit acetylcholinesterase, which is a common mechanism of action for nootropics for improving memory and concentration.

Muira puama is considered by many to be adaptogenic for its high degree of safety and non-specific improvements on the nervous system.

 

What Is Muira Puama Used For?

Muira puama is mainly used for age-related conditions involving libido, and neurological function. Traditionally the herb was used alongside catuaba which shares many of the same applications.

 

Traditional Uses of Muira Puama

+ South America

In the Amazon rainforest, Muira puama has had a long history of use for a wide range of ailments.

Every part of this plant has been used as a medicine at one time. However, this has evolved over time to using only the bark and roots.

In the Rio Negro (Brazil), the native peoples in the area used Muira Puama as a sort of panacea, especially in age-related illness. Some uses included treatments for baldness, fatigue, muscular weakness, and sexual debility.

The traditional method of preparation involves mixing Muira Puama, and Catuaba (Erythroxylum catuaba, Trichilia catigua, or Anemopaegma arvense), and infusing them in warm water overnight.

Other preparations in the Amazon using muira puama was a distilled liquor made from sugar cane called Cachaça — or in wine called Garrafadas.

Muira puama spirits were consumed daily before meals at a dose of around 60 mL [6]. This preparation would be considered a tincture by today's definition.

The natives of the Amazon also used this herb to treat what was referred to as "nervous weakness', which include symptoms such as lassitude, general lack of interest/motivation, tremors, sexual debility, [6]. It was also commonly employed in stroke recovery, and aid in coping with stressful circumstances (both emotional and physical), in the Amazon. [3].

The neuroprotective and memory enhancing effects of this herb that have been discovered may be responsible for the success of this herb for this illness.

In Brazil, Ptychopetalum has been a popular herb for a long time. It is used for debilitating diseases, to increase physical endurance, ameliorate performance in mental tasks, improve memory, and recovery from sudden weight loss (A.L Patio et al., 2010).

+ Traditional Chinese Medicine

Not commonly used. However, some non-peer reviewed articles indicate that its actions are warming in nature and enter the triple burner meridian. It is thought by some to regulate both yin and yang in the triple burner and is used as a circulation tonic.

Due to Muira puamas effects on libido, it may have some effect on the kidney meridian as well.

 

Herb Details: Muira Puama

Herbal Actions:

  • Adaptogen
  • Antidepressant
  • Stimulant (mild)
  • Aphrodisiac
  • Nootropic
  • Male tonic
  • Nervine
  • Antiulcer

Weekly Dose

Part Used

  • Bark and Roots

Family Name

  • Olacaceae

Distribution

  • South America, Amazon Rainforest

Constituents of Interest

  • Lupeol

Common Names

  • Muira Puama
  • Uiratã, Muiratam
  • Pau-homen
  • Potenzholz
  • Boise de la Puissance
  • Bois de la puissance sexuelle
  • Potency wood
  • Marapuama

CYP450

  • Unknown

Quality

  • Warm

Pregnancy

  • No adverse reactions expected.

Taste

  • Unknown

Duration of Use

  • May be used long term. Recomended to take breaks, or skip every third day.
 

Products Containing Muira Puama

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Female Libido

Herb Pharm

(Contains Muira puama and Shatvari)


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Muira Puama Capsules

Solaray

Made from Ptychopetalum olacoides root

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Muira Puama Raw Bark

Starwest Botanicals

Raw Ptychopetalum olacoides bark

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Botanical Information

Muira puama is the common name for the species Ptychopetalum olacoides, and Ptychopetalum uncinatum. These species are contained in the family Olacaceae which includes about 180 different species.

Muira puama is a small tree growing to about 15m in height, producing small, white flowers with a pungent jasmine-like fragrance. The taste of the roots and bark are a bit salty, and acrid, while the odor is faint but woody. The tree is relatively nondescript, having ovate dark green to brown leaves, and a greyish colored bark.

When scratched, the inner bark is pink in color. Muira puama is native to the Amazon rainforest, with other species of the family (Olacaceae) growing in tropical Africa.

Of the genus, there are 7 species, 2 in South America, and 5 in Africa. Of the South American species, P. olacoides is found throughout French Guyana, Guyana, Suriname, And Brazil. P. uncinatum, however, is only found in Brazil. These 2 species are virtually identical except for Lupeol content.

Both South American species are used interchangeably in traditional medicine, however P. olacoides is preferred currently due to its higher Lupeol content which is believed to be one of the active constituents of this plant. This species is also studied much more commonly than P. uncinatum.

Another completely different and unrelated species of tree found in Brazil is also referred to as Muira puama. Its botanical name is Liriosma ovata, it is also included under the Olacaceae family, however, should not be used in the same way as the Ptychopetalum species due to lack of traditional use in this area, and virtually no scientific data on the medicinal use of this plant. There is, unfortunately, an overwhelming amount of confusion over this species on various unscholarly websites and blogs, talking about Liriosma ovata as if it were the same as Ptychopetalum. The shared name Muira Puama is most likely to blame for this confusion. Many foragers and herb retailers from the Amazon will try to sell Liriosma as Muira Puama on the market as well, so it is essential to correctly identify and purchase this herb from a reputable source.

 

Habitat, Ecology, Distribution

Ptychopetalum uncinatum is found in the Brazilian portion of the Amazon rainforest, where as Ptychopetalum olacoides is found throughout the Amazon rainforest. Other species are found in tropical Africa

 

Harvesting, Collection, Preparation:

The traditional preparation involves mixing with Trichilia catigua (Catuaba), and infusing in warm water overnight, however, the medicinal constituents of Ptychopetalum is generally not soluble In water and is, therefore, better extracted into alcohol.

The majority of studies done on P. olacoides have been conducted on the ethanol extract which is then sometimes lyophilized or concentrated further with other techniques. However, the alcohol extract (tincture) is commonly used due to its simplicity.

Other methods of ingestion include powdering and encapsulation or pressing into tablets. However, these are not preferred for the same reason as infusions (not water soluble).

This herb is a by-product of the logging industry in South America. However, the devastation logging has on the rainforest biome makes this method of collection less than ideal. Skilled foragers can harvest the roots and bark of this plant without causing the same level of devastation to the surrounding area, so this method is preferred. A few websites sell this herb, and due to it being one of the more popular Amazonian herbs, it is relatively easy to find in health food, or herb shops either in encapsulated form or tincture. Online shops providing this herb can also be found quite easily. It is essential to purchase this herb from a reputable source to reduce the likelihood of using the wrong plant (Liriosma ovata), as mentioned earlier.

If preparing a tincture from the raw dried plant, it is recommended to use the highest alcohol content possible. This can be achieved from using ethanol from sources such as Everclear, or other high proof alcohols/moonshines. Clear alcohol is recommended over dark or Amber liquors to extract as many medicinal constituents as possible (dark liquors already have particles in solution, and thus can not hold as many therapeutic molecules as clear alcohol). The standard ratio from dried plants is 1:5 meaning 1 part dried plant material (in g), to 5 parts alcohol (in ml).

 

Pharmacology & Medical Research

+ Adaptogenic

The term "adaptogen" refers to plants or other substances that augment non-specific resistance in the body, and help the body to adapt to various situations. Therefore protecting it from stressful events and factors. [9]. P. olacoides has been shown to exhibit anti-stress properties [6], as well as neuroprotective, antioxidant [3], libido enhancing [2], and positive effects on memory [1]. All are suggesting its classification as Adaptogenic. One of these studies, in particular, suggested that P. Olacoides could be classified as an adaptogen due to the combined results of the effects noted above [6].

It has also been used in traditional medical systems throughout the Amazon as a "tonic" for many years. [6], thus providing generations of human testing.

A survey of Brazilian books (folk literature) [9] searched for plants with properties resembling those of an adaptogen, analyzed 24 books by authors from different areas of the country. Approximately 766 plants were suspected as being adaptogenic and analyzed further. Only species from Brazil, and cited in at least 4 books were selected for further investigation. This resulted in 33 species (24 families). Of these, 4 plants had previous research investigating effects that are considered adaptogenic in nature (anti-stress, memory enhancement, increased physical or sexual performance).

These plants included: Ptychopetalum olacoides, Paullinia cupana, Turnera diffusa, and Heteropterys aphrodisiaca.

+ Antiacetylcholinesterase

An ethanol extract of P. olacoides showed significant inhibition of acetylcholinesterase activity in vitro in the hippocampus, and striatum of rats. [4]. The cholinergic hypothesis surrounding Alzheimer's disease gives a good reason to believe that P. olacoides could be successful as a treatment to this debilitating disease.

+ Neuroprotective

Ptychopetalum olacoides has been used traditionally as the treatment for age-related illness, as well as the present day for more specific illnesses that can be classified under the same heading. P. olacoides neuroprotective effects, anti-acetylcholinesterase properties [4], Antioxidant properties [3], libido enhancing effects [2], and Anti-stress effects [6] all confirm the use of this herb to combat many age-related illnesses including libido loss, and Alzheimer's.

+ Cancer

Lupeol, a triterpene, has been shown to demonstrate anti-inflammatory, anti-mutagenic, and anti-arthritic properties both in vitro and in vivo [14]. Lupeol is found in many fruits, as well as many medicinal plants including aloe, and Ptychopetalum species. P. olacoides has a higher Lupeol content than P. uncinatum.

In pancreatic cancer (4th leading cause of cancer mortality in the USA), the only potentially curative therapy is surgical resection. However, only 15-20% of patients can be considered for surgery on presentation due to the advancement of the disease upon presentation, (Yan Liu et al., 2015). Chemotherapy also has limited efficacy on this disease, [17]. This prompts the immediate need for alternative therapies and treatments for this and similar pathologies, be it natural or synthetic. "Growing evidence suggests that natural products might be a good source to develop next-generation anti-cancer drugs" [17]. In a study conducted on the effects of Lupeol on pancreatic cancer researchers stated: "Lupeol inhibits the proliferation of growth of PCNA-1 cells".

A study done on lupeol effect specifically on colorectal cancer stated that: "our data strongly advocate the efficacy of Lupeol against CRC (colorectal cancer) cells that exhibit constitutively active Wnt/b-cetenin signaling" [14].

Lupeol anti-cancer properties have also been extensively studied on cancers such as prostate cancer, skin cancer, hepatocellular carcinoma, epidermoid carcinoma, and melanoma. [17].

+ Depression

Ptychopetalum olacoides ethanol extracts have been shown to produce anti-stress effects [6], neuroprotective effects, and promnesic effects (A.L da Silva 2008). These effects combined, have a strong influence over prevention, and treatment of the pathology of depression. A study done on the standardized ethanol extract of Ptychopetalum olacoides [8] showed a reduction in stress and increased management of stress in mice trials. The effects seem to be through the D1-dopamine receptors, and b-noradrenergic receptors, which have both been shown to be relevant in other antidepressant drugs. A P. olacoides ethanol extract has also been shown to prevent stress-induced HPA-hyperactivity, which is known to be present in depressed individuals. [5].

The long-standing use of P. olacoides in traditional medicine systems in the Amazon, also provide strong evidence of success in treating this illness with this plant. [4].

+ Infection

A study done in vitro on the antimicrobial effects of Amazon plants reported that the aqueous extract of P. olacoides (1:10 in distilled water, infused at 70c and lyophilized) had an inhibitory effect on the growth of Klebsiella ozaenae (a gram-negative bacteria), and Acinetobacter baumanniii (also gram-negative bacteria), [2]. This gives compelling evidence that P. olacoides could have antibacterial actions on other gram-negative bacteria. More research is needed in this area, however.

+ Antioxidant

A study done on the antioxidant activities of Ptychopetalum olacoides on mice [3] using an ethanol extract of P. olacoides (POEE), found reduced free radical production in the hypothalamus, as well as a significant decrease in lipid peroxidation in the cerebral cortex, striatum, and hypothalamus. A lower carbonyl content in the cerebellum and striatum were also noted. "This study suggests that POEE contains compounds able to improve the cellular antioxidant efficacy in the brain, ultimately reducing the damage caused by oxidative stress'. One of the main antioxidant compounds of this herb is reported to be Lupeol. This triterpene molecule is found in many plants and has been shown to possess antioxidant activities [12].

+ Stress

An ethanol extract of P. olacoides (POEE), has been shown to reduce stress in mice through various tests [8]. Another study out of Brazil (A.L Patio et al., 2010), found that POEE exhibited anti-stress properties in mice, measured by the light/dark test. This study made the connection between previously known neuroprotective actions, with the confirmed anti-stress actions from this study, and suggested this herb as adaptogen-like. The data found in this study indicates that this herb counteracts some of the effects caused by chronic stress. This same study showed that POEE can prevent chronic stress-induced anxiety, and although there were no direct effects found on glycemia, it effectively prevented stress-induced hyperglycemia. The extract also increased hypoxia endurance in mice when administered both orally and intraperitoneal. All of these traits are what lead researchers in this study to suggest its classification as an adaptogen.

P. olacoides has also been shown to produce anti-hypoxic effects in mice, which have a direct connection to the pathology of stress. This may be due to a combination of the antioxidant properties, and its noradrenergic potentiating ability [8].

Stress has been proven to have an effect on the pathogenesis of various diseases. Such diseases include endocrine disease (including diabetes), immunosuppression, sexual and cognitive dysfunctions, peptic ulcer, hypertension, heart disease, anxiety, depression, and ulcerative colitis. [6].

+ Anxiety

Anxiety is both a symptom and a disorder by itself. It is characterized in humans by tense and physically exhaustive alertness. [5]. An ethanol extract of P. olacoides (30, 100, and 300 mg/kg doses) all found to decrease anxious behaviors in mice through various tests.

+ Rheumatoid Arthritis

Lupeol, which is one of the more studied constituents found in many plants, has been shown to possess many amazing qualities, with anti-inflammatory being one of them. "Triterpenes are found to have anti-inflammatory activity without any toxic manifestation. The pentacyclic Triterpenes Lupeol and Lupeol linoleate were tested in adjuvant-induced arthritis in rats, showed a reduction in paw swelling by 39 and 58% respectively." [15].

+ Aphrodisiac

A study done in vitro on rabbits [2] studying the effects of the herbal compound Catuama®, and its individual constituents have shown that injections of an extract of P. olacoides caused a dose-dependent relaxation of the corpus cavernosum. Since the relaxation of the corpus cavernosum is a key step in penile erection, these results suggest a mechanism of action in treating impotence in males. The traditional use of this herb for these illnesses also adds to the evidence that P. olacoides may be useful in the treatment of impotence and erectile dysfunction.

+ Memory

An animal study done [1] showed that the ethanol extract of P. olacoides has a positive effect on memory retrieval in mice. This study investigated the role of serotonin receptors in P. olacoides effects on amnesia, and other cognitive deficits found that the extracts mechanism of action involves the anti-acetylcholinesterase effects, as well as effects on beta-adrenergic and dopamine receptors. The study also found that the effects of P. olacoides ethanol extract (POEE) were increased through a synergistic action of 5HT (2A) (but not 5HT(1A)) serotonin antagonists, spiperone. The synergism can be identified as the combined effects of 5HT antagonism, or a combination of acetylcholinesterase inhibitory effects (POEE) and 5HT antagonism. This shows that P. olacoides have a positive influence on both short-term, and long-term memory retrieval in mice through anti-acetylcholinesterase activity, as well as serotonin receptors in the brain.

+ Neuroprotective

Many neurodegenerative diseases (Parkinson's, Alzheimer's, autism, dementia, and Huntington's disease, for example) share similar traits and causative factors. Various mechanisms can be held responsible for the development of neurodegenerative diseases such as oxidative stress, protein aggregates in neurons, depletion of neurotransmitters, mitochondrial malfunction, CNS inflammation, or damage of the blood-brain barrier. (M. Rasool et al., 2014). Acetylcholinesterase as well as butyrylcholinesterase cause the breakdown of cholinesterase in the brain. Low cholinesterase has been associated with both age-related disorders leading to cognitive decline. Thus increasing the likelihood of neurodegenerative disorders to take place. [13].

Ptychopetalum olacoides has demonstrated antioxidant activity in the brain [3], anti-acetylcholinesterase activity [1], as well as anti-inflammatory effects (Lupeol) [15, 17]. All of these properties demonstrated by Ptychopetalum olacoides have direct therapeutic influence over many of the causative factors of various neurodegenerative disorders. Less directly, P. olacoides well-studied effects on the prevention and treatment of both acute and chronic stress deserve merit in the prevention and treatment of neurological disorders due to the causative factor of oxidative damage in the brain. [1].

The constituents responsible for P. olacoides anti-acetylcholinesterase, anti-inflammatory, and antioxidant activity is the triterpene Lupeol, [13]. A-pinene and B-pinene are considered to have anti-acetylcholinesterase activity as well [10].

 

Phytochemistry

The bark and roots are high in fatty acid esters (the main one being behenic acid), essential oils including beta-caryophyllene, and alpha-humulene, some phytosterols, triterpenes (including Lupeol), and an alkaloid named recently as muirapuamine.

Also contained are other novel alkaloids, free long-chain fatty acids, sesquiterpenes, monoterpenes, and esters. Lupeol is described as one of the main constituents of this herb. In one study [12] Lupeol was found to possess antioxidant properties. In other studies [14, 17]. Lupeol was shown to exhibit anti-cancer properties in various forms of cancer.

The main plant chemicals found in Muira puama include: alpha-copaene, alpha-elemene, alpha-guaiene, alpha-humulene, alpha-muurolene, alpha-pinene, alpha-resinic acid, alpha-terpinene, arachidic acid, allo-aromadendren, behenic acid, beta-bisabolene, beta-caryophyllene, beta-pinene, beta-resinic acid, beta-sitosterol, beta-transfarnesene, borneol, campesterols, camphene, camphor, car-3-ene, caryophyllene, cerotic acid, chromium, coumarin, cubebene, delta-cadinene, dotriacontanoic acid, elixene, ergosterols, eugenol, essential oils, gamma-muurolene, hentriacontanoic acid, heptacosanoic acid, lignoceric acid, limonene, linalool, lupeol, melissic acid, montanic acid, muirapuamine, myrcene, nonacosanoic acid, para-cymene, pentacosanoic acid, phlobaphene, stigmasterols, trichosanic acid, and uncosanic acid.

 

Clinical Applications Of Muira Puama:

Although the traditional method of preparation involved infusing the crushed bark in warm water overnight, the constituents in muira puama are not very water soluble. The best way to consume this herb is as an alcoholic liquid extract, or a concentrated extract made using organic solvents.

 

Cautions:

This herb may overly stimulate some individuals. Reduce the dose, or avoid taking muira puama altogether if overstimulation occurs. Side effects include insomnia and hypertension.  

May promote hypertension if taken for long periods due to its stimulating effects on the central nervous system, although few studies if any have been conducted to investigate this possibility. Consult a medical professional if taking Ptychopetalum spp. with high blood pressure.

May cause insomnia due to its stimulating effects. This may be avoided by taking a day off every 2-3 days during long term use. However, there is little evidence of this side effect in the scientific literature as well.

Avoid consuming with excessive amounts of caffeine due to possible insomnia side effects. 

 

Synergy

Traditional use of this plant commonly used catuaba (various species) alongside this plant for a wide range of ailments [11].

A formula called Catuama® containing Ptychopetalum olacoides, Trichilia catigua, Paullinia cupana, and Zingiber officinalis, has been through numerous scientific peer reviewed studies showing synergy between the botanicals in this formula [16]. Some sources report Catuama actually uses the Croton echinoides species instead of Ptychopetalum olacoides. The author has so far been unsuccessful in finding lab analysis of this preparation to confirm.

Possible synergy with Smilax species due to the absorption aiding qualities of Smilax spp.

Spiperone shows synergy through 5HT antagonism and acetylcholinesterase inhibition [1]. Other possible synergistic botanicals with a lot of suggested synergy from various web related sources without sufficient scientific evidence include Ginkgo biloba, Glycyrrhiza glabra, and Cucurbita spp. seeds.

 

Author

Justin Cooke, BHSc

The Sunlight Experiment

(Updated November 2018)

 

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References:

  1. da Silva, A. L., Ferreira, J. G., da Silva Martins, B., Oliveira, S., Mai, N., Nunes, D. S., & Elisabetsky, E. (2008). Serotonin receptors contribute to the promnesic effects of P. olacoides (Marapuama). Physiology & behavior, 95(1-2), 88-92.

  2. Antunes, E., Gordo, W. M., De Oliveira, J. F., Teixeira, C. E., Hyslop, S., & De Nucci, G. (2001). The relaxation of isolated rabbit corpus cavernosum by the herbal medicine Catuama® and its constituents. Phytotherapy Research, 15(5), 416-421.

  3. Siqueira, I. R., Fochesatto, C., Torres, I. L. S., da Silva, A. L., Nunes, D. S., Elisabetsky, E., & Netto, C. A. (2007). Antioxidant activities of Ptychopetalum olacoides (“muirapuama”) in mice brain. Phytomedicine, 14(11), 763-769.

  4. Da Silva, A. L., da Silva Martins, B., de Moura Linck, V., Herrmann, A. P., Mai, N., Nunes, D. S., & Elisabetsky, E. (2009). MK801-and scopolamine-induced amnesias are reversed by an Amazonian herbal locally used as a “brain tonic”. Psychopharmacology, 202(1-3), 165-172.

  5. Da Silva, A. L., Bardini, S., Nunes, D. S., & Elisabetsky, E. (2002). Anxiogenic properties of Ptychopetalum olacoides Benth.(marapuama). Phytotherapy Research, 16(3), 223-226.

  6. Piato, A. L., Detanico, B. C., Linck, V. M., Herrmann, A. P., Nunes, D. S., & Elisabetsky, E. (2010). Anti-stress effects of the “tonic” Ptychopetalum olacoides (Marapuama) in mice. Phytomedicine, 17(3-4), 248-253.

  7. Oliveira, A. A., Segovia, J. F., Sousa, V. Y., Mata, E. C., Gonçalves, M. C., Bezerra, R. M., ... & Kanzaki, L. I. (2013). Antimicrobial activity of amazonian medicinal plants. SpringerPlus, 2(1), 371.

  8. Piato, Â. L., Rizon, L. P., Martins, B. S., Nunes, D. S., & Elisabetsky, E. (2009). Antidepressant profile of Ptychopetalum olacoides Bentham (Marapuama) in mice. Phytotherapy research, 23(4), 519-524.

  9. Mendes, F. R., & Carlini, E. A. (2007). Brazilian plants as possible adaptogens: an ethnopharmacological survey of books edited in Brazil. Journal of Ethnopharmacology, 109(3), 493-500.

  10. Oboh, G., Olasehinde, T. A., & Ademosun, A. O. (2014). Essential oil from lemon peels inhibit key enzymes linked to neurodegenerative conditions and pro-oxidant induced lipid peroxidation. Journal of oleo science, 63(4), 373-381.

  11. Taylor, L. (2005). The healing power of rainforest herbs: A guide to understanding and using herbal medicinals (No. 615.321 T243). SquareOne publishers.

  12. Santiago, L. A., & Mayor, A. B. R. (2014). Lupeol: an antioxidant triterpene in Ficus pseudopalma Blanco (Moraceae). Asian Pacific journal of tropical biomedicine, 4(2), 109-118.

  13. Rasool, M., Malik, A., Qureshi, M. S., Manan, A., Pushparaj, P. N., Asif, M., ... & Sheikh, I. A. (2014). Recent updates in the treatment of neurodegenerative disorders using natural compounds. Evidence-Based Complementary and Alternative Medicine, 2014.

  14. Tarapore, R. S., Siddiqui, I. A., Adhami, V. M., Spiegelman, V. S., & Mukhtar, H. (2013). The dietary terpene lupeol targets colorectal cancer cells with constitutively active Wnt/β‐catenin signaling. Molecular nutrition & food research, 57(11), 1950-1958.

  15. Geetha, T., & Maralakshmi, P. (1999). Effect of lupeol and lupeol linoleate on lysosomal enzymes and collagen in adjuvant-induced arthritis in rats. Molecular and cellular biochemistry, 201(1-2), 83-87.

  16. Pontieri, V., Neto, A. S., de França Camargo, A. F., Koike, M. K., & Velasco, I. T. (2007). The herbal drug Catuama reverts and prevents ventricular fibrillation in the isolated rabbit heart. Journal of electrocardiology, 40(6), 534-e1.

  17. Liu, Y., Bi, T., Wang, G., Dai, W., Wu, G., Qian, L., ... & Shen, G. (2015). Lupeol inhibits proliferation and induces apoptosis of human pancreatic cancer PCNA-1 cells through AKT/ERK pathways. Naunyn-Schmiedeberg's archives of pharmacology, 388(3), 295-304.

  18. Novello, C. R., Marques, L. C., Pires, M. E., Kutschenco, A. P., Nakamura, C. V., Nocchi, S., ... & Mello, J. C. (2016). Bioactive Indole Alkaloids from Croton echioides. Journal of the Brazilian Chemical Society, 27(12), 2203-2209.