Plant of the day 5: Paullinia cupana (Guarana)

The planet is blessed with a rich diversity of plants but due to limiting factors such as moisture, temperature, sunshine, edaphic factors, physiographic factors, etc., the distribution of plant species is not uniform globally. These factors mitigate against the distribution of organisms generally such that plant species that grow in a particular region might find it totally difficult to survive in another region. However, with the advancement in technology, the stories are now changing and species can be genetically modified to thrive in a region where they cannot normally survive. Such species must be of huge economic importance to man either directly or indirectly.

I first got to know about the plant commonly known as Guarana from the comment of my friend @abigail-dantes after I wrote this post about Azanza garckeana, the snot apple plant. Today's post is a sequel to the promise I made to her to do a little literature search about the plant known as Guarana.

From all indications, Guarana seems to be native to the Amazon Basin which is the region of South America drained by the amazon river and its tributaries. The Basin houses one of the largest forests in the world, the Amazon forest which recently fell a victim of wildfire. However, the distribution of the plant transcends the Amazon forest or South America, it goes as far as the United States, North America, Southeast Asia up to Singapore.

Guarana grows as an evergreen woody climber that can be as tall as 13 meters. It belongs to the Sapindaceae flowering plant family otherwise known as soapberry family. The mature plant produces small white flowers and small, bright red fruits that split open at the ripened stage.

What makes Guarana an interesting plant?

Virtually everyone loves coffee. Perhaps I may be wrong but I do not think I have come across anyone that dislikes coffee, although the period of consumption does vary. Coffee is universally loved largely due to caffeine content which has stimulatory and other effects on the human body.

The usefulness of Guarana plant is largely in the black seeds present inside its fruits. The seeds contain a significant amount of caffeine, the same content found in coffee. The most interesting part is that Guarana has twice the amount of caffeine that that coffee has if taking in equal quantities. Better put, a person that consumes one gram of Guarana seeds is consuming twice the amount of caffeine of a person who consumes one gram of coffee. It has been found to be the plant with the highest amount of caffeine content (as high as 10%, coffee has 1-2% caffeine).

In addition, the seed contains other bioactive compounds such as theobromine, theophylline, saponins, other nutritive elements, and tannin which can be as high as 16%. These bioactive compounds make Guarana to have found a lot of ethnobotanical and medicinal uses.

If you have taken energy drinks in the past (for example, red bull), there is a likelihood that you have taken Guarana. Powder of roasted seeds of the plant is utilized in energy drinks. In fact, the seed is primarily used in brewing drinks in the area of the plant's nativity. Over the years, research has clearly confirmed that caffeine (and indeed, Guarana) increased energy expenditure in human subjects over a12-hour day period.

Guarana seeds have also been found to be useful in the burning of fats and hence, are usually found incorporated into weight loss products. The assertion that the seeds burn fat was further reinforced in a 2001 research by Boozer and his co-researchers who examined the short-term safety and efficacy for weight loss of an herbal supplement containing Ma Huang, Guarana and other ingredients in overweight human subjects.

One of the most remarkable uses of Guana apart form energy expenditure and fat burning is its implication in the alleviation of hot flashes and fatigue associated with cancer symptoms. In research carried out in 2006 to study the chemopreventive effects of Paullinia cupana on mouse hepatocarcinogenesis, it was found that the plant has the capacity to reduce the incidence and multiplicity of macroscopic lesions. More recently in 2015, the plant showed encouraging results in mitigating the symptoms of cancer.

Guarana has also be found to have antibacterial potentials. According to a research carried out in 2017, the ethanolic extract of guarana inhibited the growth of a strain of Staphylococcus aureus. A similar study carried out by Carvalho and his co-workers in 2016 also showed a similar result. In 2007, different solvent extracts of Guarana seed were tested against the growth of some food-borne fungi and pathogenic bacteria using agar well diffusion and broth dilution methods. The result showed that the extracts of Guarana seed have strong antimicrobial properties and the author recommended its usage in food, cosmetic and pharmaceutical industries.

A number of anecdotal evidence abounds indicating the effectiveness of Guarana seed or its extract in the treatment of a host of other diseases/abnormalities. It has been utilized in the treatment of headaches, indigestions as well as kidney dysfunction. Report also has it that the seed has been used as an analgesic and in the alleviation of menstrual cramps.

A note of warning

There is no doubt that Guarana has several nutritive and medicinal value and can be a huge source of drug in the treatment of several diseases. However, caution should be taken in the use of the seed or its product due to the high amount of caffeine and tannin it contains. Although very little toxicity of Guana is known, tannin has been reported to be responsible for several abnormalities such as loss of appetite, reduced growth rate, decreased feed efficiency, and reduced protein digestibility in studied subjects.

In addition, some studies have reported potentially harmful effects of caffeine, especially when taken in excess. These effects include elevated sugar levels in diabetic patients, depression, loss of pregnancy, etc.

Final thoughts

Guarana is a plant of numerous medicinal potentials. While some have been backed up by scientific research, others are anecdotal. More research needs to be carried out on this plant to ascertain or re-affirm the various claims.reports.

Thank you all for reading.