Musa acuminata and Musa paradisiac are two types of bananas adapted to warm and humid tropical climate, needing more than 2,000 mm of rainfall per year and rich soils to grow. Bananas have been present in our diets since long time ago, they are rich in potassium, a mineral that plays a very important role in mass bone formation and regulation of blood pressure, magnesium, selenium, phosphorous, iron, vitamins A, B1, B2, B3, B5, B6, vitamin C, vitamin E, zinc (very important to regulate sleep cycles and enhance male reproductive functions)...etc. Image: Bananas by Kevin Connors via Morgue File.
In spite most of us believe in the health benefits and multiple properties of Kela fruit (Bananas), not many people knows about their most valuable active constituent, a lectin named BanLec (from Banana Lectin), that is known to exert anti-cancer and anti-HIV properties and that has been recently the subject of scientific study for its potential pharmaceutical use in future medicines. Image: Banana tree by Melvin "Buddy" Baker under Creative Common license (CC BY 2.0).
Common name: Banana.
The image above has been taken with a 5 megapixel Panasonic Lumix DMC-LZ3S, with a CCD chip that captures enough detail for photo-quality 13 x 17-inch prints, has a 6x image-stabilized optical zoom; 2.0-inch LCD display, playback of 9, 16, and 25 images is possible on a multi-split screen, Consecutive shooting feature lets you take up to five shots per second. The camera stores images on SD memory cards.
CURIOSITY: Kela fruit (Bananas) are naturally radioactive
due to the fact that they contain a relatively high amount of potassium, more precisely potassium-40
, a radioactive isotope of potassium, however the amount of potassium per banana is marginal, being only 0,036 mg or radioactive Potassium-40 out of the 300 mg or potassium that we find on each banana .
BANLEC LECTIN FROM BANANA
BanLec is a jacalin-related lectin, a kind of sugar-binding protein, isolated from the fruit of bananas found in the Musa acuminata bananas among other banana species . Lectins play a very important role in plants, where they are mainly used during germination , but their most important attribute is played in viral infections, where some viruses use lectins to attach themselves to the cells of the host organism during infection . This property has been used by scientists to hypothesize about the possibility to use this function to inhibit certain viruses. Image right: Peachyqueen via morguefile.
As the BanLec lectin from Musa paradisiac binds to high mannose carbohydrate structures including those found on viruses containing certain particular envelope proteins such as human immunodeficiency virus type-1 (HIV-1), scientist hypothesized that BanLec might inhibit HIV-1 through binding of the HIV-1 envelope protein, gp120 . Well, the results of this study show that BanLec possesses potent anti-HIV activity BanLec is able to block HIV-1 cellular entry in the presence of BanLec. BanLec inhibits HIV-1 infection by binding to the glycosylated viral envelope and blocking cellular entry .
The relative anti-HIV activity of BanLec could be compared to other anti-HIV lectins, such as snowdrop lectin and Griffithsin, and to T-20 and maraviroc, two anti-HIV drugs currently in clinical use. BanLec is therefore a potential component for an anti-viral microbicide that could be used to prevent the sexual transmission of HIV-1 .
Additionally to the already mentioned BanLec lectin identified in the predominant proteins in the pulp of ripe bananas (Musa acuminata L.), another study identified a lectin present in plantains (Musa spp.), the plantain agglutinin was called PlanLec .
BANLEC LECTIN AND T-CELL PROLIFERATION
A specific lectin (BanLec-I) from banana (Musa paradisiac), was found able to stimulated T-cell proliferation .
In a study done in murine models using the Banana genus Musa acuminata, it was determined that it is possible that the banana lectin could be developed into a useful anti-HIV, immunopotentiating and antitumor agent . In the study the lectin was capable of eliciting a mitogenic response in murine splenocytes and inducing the expression of the cytokines interferon-gamma, tumor necrosis factor-alpha, and interleukin-2 in splenocytes .
Tumor Necrosis Factor primary role is the regulation of immune cells, but it is also able to induce fever, apoptotic cell death (natural cell death), sepsis, cachexia, inflammation, and to inhibit tumorigenesis and viral replication .
 Isolation and characterization of BanLec-I, a mannoside-binding lectin from Musa paradisiac (banana).
V L Koshte, W van Dijk, M E van der Stelt, and R C Aalberse
 A lectin isolated from bananas is a potent inhibitor of HIV replication.
Swanson MD, Winter HC, Goldstein IJ, Markovitz DM.
Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Medical Center, Ann Arbor, Michigan 48109, USA.
 Fruit-specific lectins from banana and plantain.
Peumans WJ, Zhang W, Barre A, Houlès Astoul C, Balint-Kurti PJ, Rovira P, Rougé P, May GD, Van Leuven F, Truffa-Bachi P, Van Damme EJ.
Laboratory of Phytopathology and Plant Protection, Katholieke Universiteit Leuven, Belgium.
 Musa acuminata (Del Monte banana) lectin is a fructose-binding lectin with cytokine-inducing activity.
Cheung AH, Wong JH, Ng TB.
Department of Biochemistry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
 Plant names: Porcher Michel H. et al. 1995 - 2020, Sorting Anthemis Names. Multilingual Multiscript Plant Name Database (M.M.P.N.D) - A Work in Progress. School of Agriculture and Food Systems. Faculty of Land & Food Resources. The University of Melbourne. Australia. < http://www.plantnames.unimelb.edu.au >
 Chemistry: The Practical Science by Paul B. Kelter, Michael D. Mosher ,Andrew Scot, pag. 903