Adansonia digitata / Baobab
Baobab: The Tree of Life
Since the origins of human existence, people have looked to their natural surroundings for sources of nutrition and health remedies. One of the authors (SJ), after traveling in many parts of sub-Saharan Africa and talking to traditional healers in rural communities, has found that the plants in one’s immediate vicinity often will contain a surprising amount of constituents with nutritional and medicinal benefits. One example is the baobab tree (Adansonia digitata, Malvaceae), one of the largest sub-Saharan botanicals, which the author has termed a “Cinderella species” — one that is often overlooked, but once properly researched and examined, is shown to be a novel foodstuff with significant health benefits. This article addresses some of the traditional nutritional and medicinal uses, the chemical and pharmacological profile, and scientific facts and myths of the iconic baobab tree.
INTRODUCTION
With its distinctive silhouette, broad trunk, unusual root-like branches, and large, velvety fruit, baobab is the best known of all African trees. The tree is steeped in legend, and due to the many different uses of its various parts, it is known by the local people as the “tree of life.” A large tree can hold up to 4,500 liters of water; its fibrous bark can be used for rope and cloth; its edible leaves and fruit can provide relief from sickness; and its hollow trunk can provide shelter for as many as 40 people.1 So, it is easy to see why it has earned this name.
There has been a renaissance of ethnobotanical surveys of medicinal plants, especially in the cosmetics and nutrition sectors where industry chemists and product formulators are constantly looking for new and natural healthy ingredients.2,3 Since its approval as a novel food ingredient by European Union (EU) food regulators in 2008,4 the native African baobab tree has gained increasing market and media exposure. This paper presents a study of the ethnopharmacological uses of the tree in southern Africa and its significant array of ethnobotanical and potential commercial uses.
BOTANICAL DESCRIPTION
The baobab tree is also known as the upside-down tree, boab, boaboa, bottle tree, kremetart tree, cream of tartar (not to be confused with the multipurpose ingredient potassium bitartrate, which is made from fermented grapes [Vitis vinifera, Vitaceae]) tree, or monkey bread tree. The word “baobab” is derived from the Arabic bu hobab, meaning “fruit with many seeds.” There are eight species of baobab: six are indigenous to Madagascar, one to Australia, and one to mainland Africa (A. digitata). Adansonia digitata grows in most countries south of the Sahara, although in South Africa it is restricted to the Limpopo and Mpumalanga provinces.5
A massive deciduous tree with a round or spreading crown, it can grow to heights of 20 m (approximately 65 ft). The trunk is stout, tapering, and abruptly bottle-shaped, and it can be up to 12 m (39 ft) in diameter. The bark is smooth, grayish-brown, and has heavy folds. The bark on the lower part of the trunk often bears scars from local people who harvest it to retrieve the strong fibers, and from elephants that try to obtain water from the trees. However, even with trunk damage, baobab can continue to grow and regenerate new layers of bark. The leaves are alternate and palmately compound in mature plants. The flowers are waxy, white, crinkly, and mostly solitary, growing up to 20 cm in diameter. The ovoid-shaped fruits are roughly 15 cm long with a hard, woody shell covered by velvety hairs, and they contain kidney-shaped seeds that are embedded in a powdery pulp. In sub-Saharan Africa, baobab is harvested in April and May, and flowers are harvested from November to December. The tree favors a dry, woodland habitat with rocky, well-drained soil.
Baobab is a slow-growing tree and, as such, there has been much speculation about the age of large trees and their growth rate. Carbon-dating techniques and analyses of core samples suggest that baobab trees with 10 m diameters may be around 2,000 years old.5
TRADITIONAL MEDICINAL USES
Baobab leaves, bark, and fruit are used for food and medicinal purposes in southern Africa. The bark has astringent properties and has been used traditionally to alleviate colds, fevers, and influenza (a decoction made from the fresh bark is taken as a beverage for one week to treat the flu).6 The wood, bark, and seeds of the tree are known to have anti-inflammatory properties.7 The leaves may be used as an antiperspirant, and they also have been used to treat fever, kidney and bladder diseases, as well as asthma and diarrhea.8-14 In African traditional medicine, baobab fruit pulp is used to treat fever, diarrhea, dysentery, smallpox, measles, hemoptysis (the coughing up of blood), and as a painkiller. For the treatment of infant diarrhea, a mixture made from the floury pulp mixed with millet flour and water is given to the child until cured.8 For dysentery, baobab leaves are administered orally or crushed into a drink. Leaves can also be used in hip-baths to treat parasitic skin infections. The seed can be pulped and applied externally or added to water as a drink to treat gastric, kidney, and joint diseases.15
During the rainy season when the trees are in leaf, baobab is a good fodder tree, especially for game such as elephants, kudus, nyalas, and impalas. At the end of the season, cattle eat the fallen leaves, and various game species relish the fallen flowers. As far as humans are concerned, the roots can be tapped for water, and the young roots are cooked and eaten. Young leaves can be cooked and eaten like spinach or dried and powdered to be used later. The leaves are rich in ascorbic acid (vitamin C), sugars, and potassium tartrate.16 The acid pith of the fruit is rich in vitamin C and can be used to make a refreshing drink. Baobab seeds, the oil of which is high in calories, can be eaten fresh, dried, or roasted as a substitute for coffee (Coffea spp., Rubiaceae). The pulp and seeds have high nutritional value in the form of iron, calcium, and vitamin C, and they can be fed to livestock toward the end of the dry season when grazing is poor.
The citric and tartaric acids found in the pulp inspired one of baobab’s popular names, “cream of tartar tree.” Baobab pulp is often used in baking as a milk-curdling agent, as a flavoring for yogurt and ice cream, and as a source of calcium for pregnant and lactating women. Due to its high pectin content, the pulp also has been used traditionally as a thickening agent for sauces and jams. In some African cultures, the pulp has been used as an ingredient in cosmetics.17
Baobab has a long history of use as a medicinal product. The botanist and physician Prospero Alpini (1553-1617) wrote in his book De plantis Aegypti liber that fresh baobab fruit had a very pleasing taste, and that the Ethiopians used it on burns and rashes and to cool the effects of serious fevers. For these afflictions, they either chewed the flesh of the fruit or pressed it into a juice with added sugar. Alpini also wrote that in Cairo, Egypt, where fresh baobab fruit was unobtainable, Egyptians made preparations from its powder to treat fevers, dysentery, and bloody wounds — an indication that this plant has been used medicinally for centuries.18
Local medicinal uses for baobab are richly varied.15 The bark, along with dried leaves, is made into a preparation called lalo that is used to induce sweating and reduce fever. The bark contains a quantity of edible, insoluble, acidic, tragacanth-like gum, which is used to disinfect skin ulcers and wounds. Mucilages made from baobab phloem sap in the bark are used as a remedy for gastrointestinal inflammation.15,19 The bark also is popular as a cardiotonic; this traditional use has been confirmed experimentally by researchers who demonstrated the positive inotropic effect of an ethanolic bark extract on isolated atrial muscles of rats.20
In Sierra Leone specifically, the leaves and bark are used as a prophylactic against malaria. In the Congo, a bark decoction is used to bathe children with rickets, and in Tanzania, as a mouthwash to treat toothache. In Ghana, the bark is used as a substitute for quinine in cases of fever. In southern Zimbabwe, the leaf is eaten as a vegetable, while in central Africa it is used as a diaphoretic (perspirant) against fevers, and the seeds as a remedy for dysentery. In Messina, South Africa, the powdered seed is given to relieve hiccups in children.1
In Nigeria and Senegal, baobab fruits are reputed to be effective against microbial diseases. This has been confirmed in tests against certain bacteria and fungi, although the active constituents responsible for these effects have yet to be isolated.21 A prepared root infusion is used as a bath for babies to maintain soft skin.20 Conditions including asthma, sedation, colic, fever, inflammation, diseases of the urinary tract, ear trouble, backache, wounds, tumors, and respiratory difficulty are treated orally. The leaves are considered an emollient and diuretic, and leaf decoctions are used for earache and otitis (inflammation of the outer ear, middle ear, or ear canal).15 In general, leaf preparations are used for the control of kidney and bladder diseases, asthma, fatigue, and as a tonic, blood cleanser, prophylactic, and febrifuge (a medication that reduces fever). They have also been used for diarrhea, inflammation, insect bites, the expulsion of guinea worms, internal pain, and other afflictions.
BIOLOGICAL PROPERTIES
The pulp of baobab fruit contains astringent compounds (e.g., tannins and cellulose), which exert an antidysenteric action due to an osmotic effect and an inhibitory interaction with acetylcholine, the neurotransmitter that is responsible for gut spasms. The fruit has anti-inflammatory, febrifuge, and analgesic properties due to the presence of saponins and sterols; experimental data have also shown the fruit to have hepatoprotective effects.20 The leaves have both antihypotensive and antihistaminic properties, and the leaf powder, due to its antihistaminic properties, has been suggested as an anti-asthmatic.22
Anticancer Activity
Anticancer activity is virtually unheard of in plants in the family Malvaceae, yet research suggests that A. digitata may have antitumor properties.1 In Senegal and Guinea, both a decoction and a poultice made from baobab fruit extract were shown to have antitumor activities.23,24 The specific bioactive constituents responsible for these actions have not yet been identified.
Antisickling Activity
Sickle-cell anemia is a problem that has affected Africans for centuries. One Nigerian remedy is derived from a concoction of an aqueous extract of the bark of A. digitata, which is used locally for its antisickling activity. However, after testing various concentrations on washed sickle-cell blood samples, researchers in Nigeria found that the results did not support the anecdotal reports.25
Hepatoprotective Influence
In vitro studies in Saudi Arabia have shown that aqueous extracts of A. digitata pulp demonstrate hepatoprotective activity against carbon tetrachloride administered in rats. Consumption of certain Adansonia fruits may play an important role in human resistance to liver damage. The mechanism of action for liver protection is unknown, but it may be due to the triterpenoids, beta-sitosterol, beta-amyrin palmitate, alpha-amyrin, and/or ursolic acid in the fruit.26
Antiviral, Antibiotic, Anti-inflammatory, Antipyretic, and Analgesic Effects
Researchers in Togo, western Africa, and Canada studied 19 medicinal plants of Togo and analyzed them for antiviral and antibiotic activity. Of the 19 species studied, 10 demonstrated significant antiviral activity, and all but two showed antibiotic activity. A. digitata was the most potent, exhibiting activity against each of the three tested viruses (herpes simplex, Sindbis, and polio).27 Further antimicrobial tests undertaken in Nigeria confirmed the aforementioned results.21
Aqueous extracts of baobab fruit have exhibited marked anti-inflammatory, antipyretic (in rats given 400 and 800 mg/kg dosages), and analgesic (in mice two hours after administration) effects.28,29 Phytochemical examination has revealed the presence of sterols, triterpenes, saponins, tannins, and glycosides, which may play a role in these actions.
Other studies support baobab’s anti-inflammatory and antiviral activities as well. In one experiment, baobab leaves, fruit pulp, and seeds were extracted with three different solvents: water, methanol, and dimethyl sulfoxide (DMSO).7 Researchers compared the three extracts to determine the minimum concentration required to inhibit 100% of three viruses (herpes simplex, influenza, and respiratory syncytial virus), and assessed their effects on cytokine secretion (interleukin [IL]-6 and IL-8) in human cell cultures. Cytokines are cell-signaling proteins that play an important role in the immune system. The leaf extracts exhibited the most potent antiviral properties, particularly the DMSO extracts, and the influenza virus was the most susceptible virus. Pulp and seed extracts were less active but still showed significant results. Cytotoxic activities of the extracts were evident only at much higher concentrations. Additionally, the researchers found that the extracts — particularly the leaf extracts — acted as cytokine modulators, meaning that they possessed anti-inflammatory activity. Overall, the results indicate the presence of multiple bioactive compounds in different parts of the plant, which may explain some of the medical benefits attributed to traditional leaf and pulp preparations. These promising results highlight the urgent need for more scientific research to be conducted on the baobab tree.
Antioxidant Capacity
Epidemiological evidence has linked intake of vitamin C and other antioxidant micronutrients to health benefits, by virtue of their capacity to trap reactive oxygen species (ROS) that are associated with degenerative diseases and damage to biological systems.30 Current scientific evidence has helped boost consumer interest in supplementing the diet with antioxidants, especially those derived from natural sources. Baobab fruit pulp is a valuable source of vitamin C, while baobab leaves contain provitamin A.13 The red funicles (threadlike stalks that connect seeds to the ovary wall) present in the fruit have an impressive antioxidant capacity, higher than in other parts of baobab and in many other fruits as well (Table 1).12,31 However, the exact antioxidant composition in baobab has not yet been determined.
The method most widely used to measure antioxidant activity involves generating radical species and analyzing the antioxidants that cause the disappearance of these radicals. The scavenging activity of antioxidants is measured against a reference compound, such as Trolox, a water-soluble equivalent of vitamin E. Most published antioxidant activity investigations conducted on baobab have focused on fresh leaves only.12
Vertuani et al. investigated the fresh fruit pulp, fruit shell, and dry leaves of baobab and compared the antioxidant values to those of other commonly consumed fresh fruits with high levels of vitamin C, including orange (Citrus sinensis, Rutaceae), kiwi (Actinidia chinensis, Actinidiaceae), apple (Malus domestica, Rosaceae), and strawberry (Fragaria × ananassa, Rosaceae).12 In this study, antioxidant activity was measured with a photochemiluminescence method of aqueous/methanol extracts from baobab products. This method allows for the measurement of the antioxidant capacities of both water- and lipid-soluble components. In water-soluble fractions, antioxidants such as flavonoids and vitamin C can be detected, while in lipid-soluble fractions, tocopherols and carotenoids can be measured.32,33 Baobab products displayed the highest capacity. Notably, dry leaves exhibited an antioxidant capacity of approximately 6.4 mmol (millimoles) of Trolox equivalents per gram of tested product (Table 1). In comparison to the baobab fruit pulp, kiwi, orange, strawberry, and apple all showed a much lower antioxidant capacity.12 However, comparing fresh fruit to dry fruit is misleading since baobab fruit is naturally dry, but these figures represent the best data available, and are a fairly good indication of baobab’s antioxidant capacity.
With regard to the lipid-soluble antioxidant component, baobab fruit pulp also showed the highest antioxidant capacity (4.15 mmol/g), followed by the dry leaves (2.35 mmol/g). The other fruit pulps had very limited capacity, which may be due to their low levels of lipid-soluble antioxidants.12
To account for the potential effects of secondary antioxidant products, and to avoid underestimation of antioxidant activity, the oxygen radical absorbance capacity (ORAC) assay can be used to follow reactions for extended periods of time. With this method, values are also reported as Trolox equivalents. Seasonal variation in fruit products, different methods of extraction, and treatment of samples can lead to differences in the outcome values. Absolute ORAC values are more significant when the test materials are in the same condition.31
In a study using ORAC values to compare the antioxidant capacities of baobab and so-called “superfruits” (Baobab Foods, unpublished data, 2011), the baobab red funicle was found to contain the highest level of antioxidants compared to goji berry (Lycium barbarum, Solanaceae), pomegranate (Punica granatum, Lythraceae), and cranberry (Vaccinium macrocarpon, Ericaceae), with the exception of the açaí berry (Euterpe oleracea, Arecaceae). Baobab fruit pulp has an ORAC value twice as high as those of cranberry and pomegranate. These data suggest potential antioxidant benefits from the consumption of baobab-containing products, although these results have been difficult to replicate and validate.
In a separate study of African fruits and culinary spices, A. digitata fruit once again showed high antioxidant capacity along with the highest amount of total phenolics (237.68 mg gallic acid equivalents/g) and total flavonoids (16.14 mg vitamin E/g) of the botanicals tested.34 Researchers reported IC50 (the half maximal inhibitory concentration) values of 8.15 µg/mL and 9.16 µg/mL using the DPPH (a standard antioxidant assay using 2,2-diphenyl-1-picrylhydrazyl) and ABTS (an enzyme assay using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assays, respectively. The FRAP (ferric reducing ability of plasma) assay determined a Trolox equivalent antioxidant capacity of 0.75 mmol/g.
CONSTITUENTS
Small Molecules
Acids, terpenoids, and flavonoids
Adansonia digitata fruit contains organic acids such as citric, tartaric, malic, and succinic acids, and its seeds yield oil that contains oleic, linoleic, and linolenic acids, as well as cyclopropenic fatty acids.8,16 Baobab also contains terpenoids, such as α- and β-amyrin palmitate, β-sitosterol, and ursolic acid.
In the 1980s, researchers in India identified two new flavonol glycosides from the roots of A. digitata, namely 3,7-dihydroxy flavan-4-one-5-O-β-D-galactopyranosyl (1→4)-β-D-glucopyranoside from the benzene extract of the water-insoluble fraction of the ethanolic root extract, and quercetin–7-O-β–D-xylopyranoside from spectral data and chemical studies of an ethyl acetate stem extract.35,36 Further investigation has identified another flavanone glycoside, fisetin-7-O-α-L-rhamnopyranoside, in the roots of baobab.37
Macromolecules
Polysaccharides
Published research has shown that baobab fruit pulp contains sugars but no starch and is an excellent source of vitamin C, calcium, and pectin. The fruit pulp is composed of carbohydrates (75%), proteins (2.5%), and a limited amount of lipids.20 It also contains fibers (50%), both soluble and insoluble, which are composed mainly of pectin. Pectin levels range from 23.4-33.8 mg/100 g depending on varieties and geographical location.38,39
Recently, researchers have focused on the potential gut health benefits associated with pectin, which exhibits health-promoting properties in the gastrointestinal tract. This polysaccharide has shown potential as a prebiotic, as it enhances the growth of probiotic bacteria in the large intestine. Studies have shown that pectin prevents pathogenic bacteria from binding to the intestinal wall, and that it chelates heavy metals, which are then excreted through urine.40-42
Adansonia digitata’s leaves and bark have been reported to contain an alkaloid called adansonin, which is used as an antidote to strophanthin, a poisonous cardiac glycoside alkaloid that is present in vines of the genus Strophanthus (Apocynaceae). This is important to locals since strophanthin is used as an arrow poison in Africa. Previously, adansonin was sold as a substitute for quinine due to its febrifuge properties.43,44 However, it is not clear whether adansonin is a pure compound or if it is indeed an alkaloid. It is possible that the substance is a mixture of compounds, but more structural research is needed. Baobab leaves are also rich in mucilage that contains uronic acids, rhamnose, and other sugars.
Micronutrients
Minerals and trace elements
Calcium, potassium, magnesium, and iron are abundant in baobab.38 In general, it is rare for calcium to be found in large quantities in fruits and vegetables, but baobab dried fruit pulp contains large amounts of this micronutrient, ranging from 257-370 mg/100 g. The leaves contain even greater amounts (307-2640 mg/100 g dry weight).45 These quantities rival those of other good dietary sources of calcium — for example, dried skim milk (960-1890 mg/100 g) — but it is much higher than levels present in other fruits and vegetables.16 Baobab contains four times the amount of calcium found in dehydrated apricots (Prunus spp., Rosaceae), and 13 times that in dehydrated apples.46 Whether or not the calcium is in a form suitable for absorption via oral administration is currently under review.
Baobab dried fruit pulp also has the highest concentration of potassium, magnesium, copper, and manganese among popular dehydrated fruits, and the second-highest concentration of zinc. The magnesium content of baobab is similar to that of dehydrated bananas (Musa acuminata, Musaceae), whereas iron levels are comparable to those found in dehydrated apricots and peaches (Prunus persica, Rosaceae).38 Based on the European Recommended Daily Allowances (RDAs) for calcium, iron, and magnesium of 800 mg, 14 mg, and 375 mg, respectively, baobab powder could prove to be a useful dietary source of these minerals, provided that sufficient amounts could be added to a product to enable a label claim. In order to make an on-label claim in Europe, the product must contain 15% of the RDA of the vitamin or mineral per 100 g, or per single-serving package.16,46
Vitamins
The main vitamins found in baobab include vitamin C and various B vitamins. On average, baobab ripe pulp has a vitamin C content of approximately 107 mg/100 g, which will remain stable for months if protected from moisture. Even if no precautions are taken, appreciable quantities of the vitamin will endure in the pulp for many years. One study found that baobab ripe pulp stored in a glass bottle showed no signs of bacterial or fungal decomposition after two years.47
Baobab dried fruit pulp contains significantly higher levels of vitamin C than other commonly consumed dried fruits16 (Table 2). Obtaining the dried pulp traditionally involves minimal processing, which helps preserve heat- and moisture-sensitive vitamins. Vitamin C is present in an amount of about 300 mg/100 g of dried fruit pulp15 — six and a half times higher than that of oranges (46 mg/100 g), five times higher than that of strawberries (61 mg/100 g), and 10 times higher than that of dried peaches and apricots.9,38 Baobab fruit pulp, naturally in powdered form, contains levels of vitamin C ranging from 34-499 mg/100 g. (According to the unofficial African Herbal Pharmacopoeia, such levels depend on the source, with pharmacopeial-grade material containing the largest amounts.48) Based on the European RDA of 80 mg of vitamin C, baobab fruit pulp powder added to an ingestible product could provide an adequate daily source of vitamin C.
In a study that assessed the vitamin B1 (thiamine) and B2 (riboflavin) contents in A. digitata, the leaves were found to contain higher levels of vitamin B2 than vitamin B1, with the most vitamin B2 (1.04 ± 0.05 mg/100 g dry matter) found in baobab leaves from Senegal. The highest iron content (26.39 mg/100 g) was found in leaves from Mali.45
Macronutrients
Fiber
In terms of macronutrients, baobab dried fruit pulp is low in fat and consists of approximately 50% fiber. It is relatively low in protein but contains numerous amino acids.16 Baobab dried fruit pulp therefore would be ideal as a fiber-supplementing ingredient in foods, raising the overall nutritional profile. According to the EU Nutrition and Health Claims Directive (No. 1924/2006), a claim that a food is a source of fiber may be made only if the product contains a minimum of 3 g/100 g, or at least 1.5 g/100 kcal.50A claim that a food is high in fiber may be made only if the product contains a minimum of 6 g/100 g, or at least 3 g/100 kcal. No specific information is available on the glycemic index (GI) or satiating effects of baobab, but its profile, compared to other foods, would indicate that it may have the potential to be a low-GI and satiating ingredient due to its low sugar and high soluble fiber content.43,51
Baobab vs. Superfruits: Comparing Nutritional Content
To date, the oft-used marketing term “superfruit” does not have an official regulatory definition, but products marketed as superfruits are generally high in a variety of nutrients and thus are associated with health benefits. Fruits currently marketed as superfruits include açaí berry, blueberry (Vaccinium spp.), cranberry, goji berry, mangosteen (Garcinia mangostana, Clusiaceae), and pomegranate, and some have suggested adding baobab to the list as well.
When comparing the micronutrients found in baobab to those found in superfruits, one must take into account that values for baobab are for the dried fruit pulp, whereas the data for superfruits are for raw foods. The vitamin C content of baobab dried fruit pulp is up to five times higher than that of raw blueberries and 15 times higher than that of pomegranates. It has much higher levels of niacin (vitamin B3), slightly higher levels of vitamin B1, and about the same amount of vitamin B2 as the selected superfruits. Baobab dried fruit pulp has also been found to contain greater quantities of calcium, magnesium, and iron. It is worth noting that removing water from fresh fruit concentrates the nutrients, so it may be an unfair comparison. However, as baobab is naturally dry, the situation is unavoidable.
In summary, baobab fruit pulp has the following:
Vitamins B1 and B2, and a high natural vitamin C content (at least 100 mg/100 g);
Strong antioxidant properties with an Integral Antioxidant Capacity of 11.1 mmol/g, which is significantly higher than that of orange pulp (10.2 mmol/g) and grape seed oligomers (10.25 mmol/g);
Minerals, including calcium (293 mg/100 g), phosphorus (96-118 mg/100 g), iron (7-8.6 mg/100 g), and potassium (2.31 mg/100 g);
Low amounts of fat and high levels of soluble fiber;
High levels of pectin, making it a useful binding and thickening agent;
Organic acids such as ascorbic, citric, malic, and succinic acids, which contribute to baobab’s bitter taste.
COMMERCIAL USES
Nutritional Applications
Since baobab obtained approval from EU regulators in 2008 as a novel food ingredient, the United Kingdom has been increasing imports of powdered baobab fruit for use as a healthy additive to snack foods and beverages. In the UK, the amount of baobab dried pulp that can be added to foods, such as cereal bars and smoothies, ranges from 10-20% (typically 5-10 g).16 This should be kept in mind when assessing baobab’s contribution to the product’s overall nutritional intake.
A 2008 report by the UK-based Natural Resources Institute estimated that trade in baobab fruit could be worth up to $961 million per year for African producers — it is currently valued at $11 million.13 African producers export approximately 20 tons of baobab each year, and the growing industry is crucial in bringing money to local people who harvest and process the fruit.
Baobab fruit pulp is currently available as a milled and sifted, free-flowing, light-colored powder, as well as a de-pectinized extract, and in the form of leaf extracts, fruit fiber (funicles), or fruit seed oil. The powder can be taken in its pure form as is done traditionally, but it can also be stirred into porridge, yogurt, or smoothies to appeal to a Western diet. Companies in Europe and North America offer baobab food products in a variety of forms, including sauces, jams, bars, and fruit chews, among others.
Skin and Cosmetic Benefits
In addition to its nutritional value, baobab has been shown to be beneficial for skin care. Studies suggest that baobab preparations can promote skin cell regeneration and tone, tighten, and moisturize the skin.17,20,52 These effects may be due, in part, to baobab’s vitamin A, D, and E content. The fruit pulp provides a complex of vitamins that exerts a variety of positive, synergistic actions, including the following: emollient effects (vitamin A), the control of sebaceous gland excretion (vitamin B6), the induction of melanin synthesis (vitamin B1/B2 complex), antioxidant defense and collagen synthesis stimulation (vitamin C), improvement of cutaneous circulation (vitamin B4), action against lipid peroxidation (vitamin E), and defense from tissue matrix degradation (triterpenic compounds).20
Fiber contained in the pulp also promotes anti-aging and antioxidant effects on the skin. Leaf extracts have antioxidant, emollient, and soothing properties, keeping skin soft and elastic while also exerting antibacterial activity. The fatty oil from the seeds improves the firmness, hydration, and lightness of the skin. It also has soothing and anti-inflammatory effects due to essential oils, hydrocarbons, and sterols, making it an ideal treatment for dry skin and the prevention of wrinkles. Baobab seed oil can heal abrasions, sunburns, and hematomas, and promote tissue regeneration.17
References
1. Wickens GE. The Baobabs: Pachycauls of Africa, Madagascar and Australia. Cham, Switzerland: Springer Science & Business Media; 2008.
2. Ashidi JS, Houghton PJ, Hylands PJ, Efferth, T. Ethnobotanical survey and cytotoxicity testing of plants of southern-western Nigeria to treat cancer, with isolation of cytotoxic constituents from Cajanus cajan Millsp. J Ethnopharmacol. 2010;128:501-512.
3. Li JW, Vederas JC. Drug discovery and natural products: end of an era or an endless frontier? Science. 2009;325:161-165.
4. Commission Decision of 27 June 2008 authorising the placing on the market of baobab dried fruit pulp as a novel food ingredient under Regulation (EC) No 258/97 of the European Parliament and of the Council. Official Journal of the European Union. 2008;183:38-39. Available at: http://acnfp.food.gov.uk/sites/default/files/mnt/drupal_data/sources/files/multimedia/pdfs/commdec2008575ec.pdf. Accessed October 8, 2015.
5. Baum DA, Small RL, Wendel JF. Biogeography and floral evolution of baobabs (Adansonia, Bombacaceae) as inferred from multiple data sets. Syst Biol. 1998;47(2):181-207.
6. Sulaiman LK, Oladele OA, Shittu IA, Emikpe BO, Oladokun AT, Meseko A. In-ovo evaluation of the antiviral activity of methanolic root-bark extract of the African baobab (Adansonia digitata Lin). African Journal of Biotechnology. 2011;10(20):4256-4258.
7. Vimalanathan S, Hudson, J. Multiple inflammatory and antiviral activities in Adansonia digitata (baobab) leaves, fruits and seeds. Journal of Medicinal Plants Research. 2009;3(8):576-582.
8. Lockett CT, Calvert CC, Grivetti LE. Energy and micronutrient composition of dietary and medicinal wild plants consumed during drought. Study of rural Fulani, northeastern Nigeria. International Journal of Food Sciences and Nutrition. 2000;51(3):195-208.
9. Lunven P, Adrian J. Intérêt alimentaire de la feuille et de la pulpe du fruit de baobab (Adansonia digitata). Ann Nutr. 1960;14:263-276.
10. Obizoba IC, Anyika JU. Nutritive value of baobab milk (gubdi) and mixtures of baobab (Adansonia digitata L.) and hungry rice, acha (Digitaria exilis) flours. Plant Foods Hum Nutr. 1994;46(2):157-165.
11. Nour AA, Magboul BI, Kheiri NH. Chemical composition of baobab fruit (Adansonia digitata L). Trop Sci. 1980;22:383-388.
12. Vertuani S, Braccioli E, Buzzoni V, Manfredini S. Antioxidant capacity of Adansonia digitata fruit pulp and leaves. Acta Phytotherapeutica. 2002;V:2. Available at: www.baobabfruitco.com/pdf/Pdf/2008/2003_02_ActaPhytoTerAntioxidant.pdf. Accessed October 21, 2015.
13. Phytotrade/LFR summary report. Nutritional evaluation of baobab dried fruit pulp and its potential health benefits. London, UK; July 2009.
14. Sidibe M, Williams JT. Baobab. Adansonia digitata. International Centre for Underutilised Crops: Southampton, UK; 2002.
15. Kamatou GPP, Vermaak I, Viljoen AM. An updated review of Adansonia digitata: a commercially important African tree. South African Journal of Botany. 2011;77(4):908-919.
16. Food Standards Agency. McCance and Widdowson’s The Composition of Foods. 6th ed. Cambridge, UK: Royal Society of Chemistry; 2002.
17. Vermaak I, Kamatou GPP, Komane-Mofokeng B, Viljoen AM, Beckett K. African seed oils of commercial importance — cosmetic applications. South African Journal of Botany. 2011; 77(4):920-933. Available at: www.researchgate.net/profile/Guy_Paulin_Kamatou/publication/236011534_African_seed_oils_of_commercial_importance__Cosmetic_applications/links/00b49515ad9885ba8b000000.pdf. Accessed October 7, 2015.
18. Alpini, P. De Plantis Aegypti. Venice; 1592.
19. Mueller MS, Mechler E. Medicinal Plants in Tropical Countries. New York, NY: Thieme Medical Publishers; 2004.
20. Burlando B, Verotta L, Cornara E, Bottini-Massa E. Herbal Principles in Cosmetics – Properties and Mechanism of Action. Boca Raton, FL: CRC Press; 2010.
21. Hussain HSN, Deeni YY. Plants in Kano ethnomedicine: screening for antimicrobial activity and alkaloids. Int J Pharmacognosy. 1991;29(1)51-56.
22. Hostettmann K, Marston A, Ndjoko K, Wolfender JL. The potential of African plants as a source of drugs. Current Organic Chemistry. 2000;4:973-1010.
23. Sebire, RPA. Les Plantes Utiles du Senegal. Paris;1899:341.
24. Kerharo J, Adam JG. La Pharmacopée Sénégalaise Traditionelle — Plantes Médicales et Toxiques. 1974.
25. Adesanya SA, Idowu TB, Elujoba A. Antisickling activity of Adansonia digitata. Planta Med. 1988;54(4):374.
26. Qarawi A, Damegh M, Mougy S. Hepatoprotective influence of Adansonia digitata pulp. Journal of Herbs, Spices & Medicinal Plants. 2003;10(3):1-6.
27. Ananil K, Hudson JB, De Souzal C, et al. Investigation of medicinal plants of Togo for antiviral and antimicrobial activities. Pharmaceutical Biology. 2000;38(1):40-45. Available at: http://stipulae.johnvanhulst.com/DOCS/PDF/InvestigationAntiviralActivity_MedicinalPlantOfTogo.pdf. Accessed October 21, 2015.
28. Kaboré D, Sawadogo-Lingani H, Diawara B, Compaoré CS, Dicko MH, Jakobsen M. A review of baobab (Adansonia digitata) products: effect of processing techniques, medicinal properties and uses. African Journal of Food Science. 2011;5(16):833-844.
29. Ramadan, A. Harraz F, El-Mougy, S. Anti-inflammatory, analgesic and antipyretic effects of the fruit pulp of Adansonia digitata. Fitoterapia. 1994;65:418-422. Available at: www.mightybaobab.com/scientific-papers/Anti-Inflammatory-OralToxicity-BaobabPulp.pdf. Accessed October 7, 2015.
30. Elsayed NM. Antioxidant mobilization in response to oxidative stress: a dynamic environmental-nutritional interaction. Nutrition. 2001;17:828-834.
31. Nutrient Data Laboratory, Agriculture Research Service, US Department of Agriculture. Oxygen radical absorbance capacity (ORAC) of selected foods. 2007. Available at: www.functionalfood.org.tw/fodinf/food_inf970220-1.pdf. Accessed October 7, 2015.
32. Popov I, Lewin G, Baehr R. Photochemiluminescent detection of antiradical activity. I. Assay of superoxide dismutase. Biomed Biochem Acta. 1987;46:775-779.
33. Osman MA. Chemical and nutrient analysis of baobab (Adansonia digitata) fruit and seed protein solubility. Plant Foods Hum Nutr. 2004;59(1):29-33.
34. Dzoyem JP, Kuete V, McGaw LJ, Eloff JN. The 15-lipoxygenase inhibitory, antioxidant, antimycobacterial activity and cytotoxicity of fourteen ethnomedically used African spices and culinary herbs. J Ethnopharmacol. 2014;156:1-8.
35. Chauhan JS, Kumar S, Chaturvedi R. A new flavanonol glycoside from Adansonia digitata roots. Planta Med. 1984;50:113.
36. Chauhan JS, Chaturvedi R, Kumar S. A new flavonol glycoside from the stem of Adansonia digitata. Indian J Chem. 1982;21(B):254-256.
37. Chauhan JS, Kumar S, Chaturvedi R. A new flavanone glycoside from the roots of Adansonia digitata. Nat Acad Sci Lett. 1987;10:177-179.
38. Chadaré F, Linnemann A, Hounhouigan J, Nout M, Van Boekel MA. Baobab food products: a review on their composition and nutritional value. Crit Rev Food Sci Nutr. 2009;49(3):254-74.
39. Brown L, Rosner B, Willett WW, Sacks FM. Cholesterol-lowering effects of dietary fiber: a meta-analysis. American Journal of Clinical Nutrition. 1999;69:30-42
40. Rhoads J, Manderson K, Hotchkiss AT, et al. Pectic oligosaccharide mediated inhibition of the adhesion of pathogenic Escherichia coli strains to human gut culture cells. Journal of Food Protection. 2008;71:2272-2277.
41. Schols HA, Visser RGF, Voragen AGJ, eds. Pectins and Pectinases. Wageningen, Netherlands: Wageningen Academic Publisher; 2009.
42. Liu LS, Fishman ML, Hicks KB. Pectin in controlled drug delivery. Cellulose. 2007;14(1):15-24.
43. Bamalli Z, Abdulkarim SM, Hasanah MG, Karim R. Baobab tree (Adansonia digitata L) parts: nutrition, applications in food and uses in ethno-medicine — a review. Annals of Nutritional Disorder and Therapy. 2014;1(3):1-9.
44. Gebauer J, El-Siddig K, Ebert G. Baobab (Adansonia digitata): a review on a multipurpose tree with promising future in the Sudan. Die Gartenbauwissenschaft. 2002;67:155-160.
45. Hyacinthe T, Charles P, Adama K, et al. Variability of vitamins B1, B2 and minerals content in baobab (Adansonia digitata) leaves in East and West Africa. Food Sci Nutr. 2015;3(1):17-24.
46. Souci SW, Fachmann W, Kraut H. Food Composition and Nutrition Tables. 6th ed. Stuttgart, Germany: Medpharm Scientific Publishers, CRC Press; 2000.
47. Carr WR. The baobab tree: a good source of ascorbic acid. Central African Journal of Medicine. 1958;4(9):372-374. Available at: http://opendocs.ids.ac.uk/opendocs/bitstream/handle/123456789/6462/Carr,%20W.R.%20%20CAJM%20%20vol.%204,%20no.%209.pdf?sequence=1. Accessed October 21, 2015.
48. Brendler T, Eloff JN, Gurib-Fakim A, Phillips LD, eds. African Herbal Pharmacopoeia. Port Luis, Republic of Mauritius: Association for African Medicinal Plant Standards; 2010:7-13.
49. Sena LP. Analysis of nutritional components of eight famine foods of the Republic of Niger. Plant Foods for Human Nutrition. 1998;52:17-30.
50. Commission regulation (EC) No 1924/2006 of 20 December 2006 on nutrition and health claims made on foods. Official Journal of the European Union. 2006;404:9-25. Available at: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2006:404:0009:0025:EN:PDF. Accessed September 14, 2015.
51. Coe SA, Clegg M, Armengol M, Ryan L. The polyphenol-rich baobab fruit (Adansonia digitata L.) reduces starch digestion and glycemic response in humans. Nutr Res. 2013;33(11):888-896.
52. Tanabe H. Cosmetic composition. Japanese patent 2008-127281. 2008. Available at: www.directorypatent.com/JP/2008-127281.html. Accessed October 19, 2015.
53. Starwest Botanicals most important quality assurance tests. Starwest Botanicals website. Available at: www.starwest-botanicals.com/content/quality_assurance.html. Accessed October 19, 2015.
54. Commission regulation (EC) No 1881/2006 of 19 December 1006 setting maximum levels for certain contaminants in foodstuffs. Official Journal of the European Union. 2006;364:5-24. Available at: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2006:364:0005:0024:EN:PDF. Accessed September 14, 2015.
Baobab: The Tree of Life ¬– An Ethnopharmacological Review by Simon Jackson
HerbalGram. 2015; American Botanical Council
Over de apenbroodboom
‘Ik geloof niet dat iemand ooit een dergelijke boom gezien heeft’, zei de Fransman Adanson, toen hij in 1749 Senegal bezocht. Hij bedoelde een boom die 20 m hoog was met een stam van 8 m doorsnede. David Livingstone noemde hem later ‘ een wortel die verkeerd om ingeplant is’.
Volgens een Afrikaanse legende heeft de duivel in een woedende bui deze boom uit de grond getrokken om hem er later verkeerd om weer in te duwen. Dat is de reden waarom vele mensen hem kennen als ‘boom die op zijn hoofd staat’. Hij is één van de meest bekende bomen in Oost-Afrika, hoewel men zijn nog grotere familieleden op Madagaskar en in Australië vindt.
Naamgeving Adansonia
De botanische naam Adansonia heeft de boom te danken aan de Fransman Michel Adanson die deze boom na zijn reis naar Senegal voor het eerst heeft beschreven. Digitata betekent voorzien van vingers wat betrekking heeft op de vingervormige bladeren. In het Swahili noemt men de boom Mbuyu (spreek em- baj- joe) wat marktboom betekent. De aangename schaduw die hij heeft wanneer hij in blad staat is ideaal als marktplaats.
De naam apebroodboom heeft hij te danken aan de bavianen die van de vlezige vruchtkern en de zaadkernen houden. Andere kleine apen en vogels leven in de kruin van de boom en gebruiken hem als speel-en nestplaats.
Plantkenmerken van de baobab
Apebroodbomen groeien als solitairs op de Afrikaanse savanne en het droge, hete bushland. Meestal zijn oude apebroodbomen breder dan ze hoog zijn. Zij kunnen een hoogte van 15 m tot 20 m bereiken. Het meest sensationeel is de enorme stam van deze reuzen, waarvan de omtrek bij oude exemplaren 30 m kan bedragen.
Apebroodbomen behoren bij de de langst levende bomen van de aarde. Hun stam is vaak hol, maar dat beïnvloedt niet hun stabiliteit. Zij kunnen zelfs een brand in het binnenste van hun stam overleven.
Olifanten rammen gaten in de zachte stam om aan de vochtige gedeelten van het vezelige hout te komen. Meestal maakt het de bomen niets uit, maar soms zakt een reus in elkaar als gevolg van de vernielingen door dikhuiden.
Tijdens het droge seizoen(6 tot 7 maanden) is de boom kaal. Kort voor de regentijd verschijnen zijn vingervormige bladeren, die aan een gespreide hand doen denken. Zij bestaan uit drie tot negen enkele gave blaadjes. Als de boom begint uit te botten, verschijnen er ook grote witte bloemen die als parasols in de boom hangen en een onaangename geur verspreiden die aantrekkelijk is voor vleermuizen.
Zij gaan open tussen de late namiddag en zonsondergang en zijn de volgende dag helemaal open. Zij worden tijdens de nacht bestoven door de vliegende honden (een soort vleermuis). Inboorlingen vermengen het stuifmeel met water en gebruiken dit mengsel dan als kleefstof.
Uit het bolvormige vruchtbeginsel ontstaan ovale vruchten, omhuld door een harde, houten schil en bedekt met geelachtig-grijs, fluwelig vilthaar. De zaadkernen zijn ingebed in de witte, poederachtige kern.
De 40 cm lange vruchten hangen aan stelen naar beneden. Zij voelen zacht aan en lijken op apenstaarten. De Engelsen noemen deze boom ook wel dead-rat-tree omdat zij menen dat de vruchten op dode ratten lijken.
Tijdens de korte regenperiode zuigt de baobab met zijn sponsachtige vezels veel water op dat hij in zijn stam opslaat. De stam is aan zijn top meestal hol. Hier worden regenwater en dauw verzameld . Men neemt aan dat een stam van ca 200 kubieke meter inhoud 140 000 l water kan opslaan. Wanneer men stukken uit de stam slaat, kan men er drinkwater uitpersen.
De schors is opvallend glanzend, grijs, zacht en knoestig, soms diep ingekerfd.
Gebruik van de Adansonia
Voor de inheemse bevolking is de boom een geschenk van God. Zij noemen hem daarom ook ‘boom des levens’. Volgens wetenschappelijk onderzoek bestaan er exemplaren die ouder dan 3000 jaar zijn. De boom levert aan de mensen voeding, water, kleding, snoep, materiaal om daken te dekken, kleefstof, materiaal voor sierraden en medicijn. Het hout van de stam is niet geschikt als brandstof omdat hij te vochtig is. Maar de vezelige bast onder de buitenste schors wordt gebruikt om er touw van te maken voor netten, matten, weefsel, hoeden, kano, bladen, kisten, manden en papier. De jonge loten en bladeren worden gekookt en als groente gegeten. Zij bevatten suiker en vitamine C. In Noord-Afrika maalt men de bladeren fijn en voegt ze dan als smaakmaker toe aan koeskoes (soort gierst).
Nadat men de zaden geroosterd heeft, maakten men er koffie van. Het vlezige deel van de zaden is grondstof voor bier en olie.
Het witte, licht zure vruchtvlees en de zaden zijn rijk aan vitamine C, B, calcium en citroen- en wijnsteenzuur. Men kan het gebruiken om deeg te laten rijzen. Hij wordt daarom ook ‘wijnsteenboom’ genoemd. Soms maakt men van het vruchtvlees een drankje dat naar citroen smaakt, wat hem de naam ‘citroenboom’ heeft opgeleverd.
Bijna alles van de boom wordt ergens voor gebruikt. De vruchtschil gebruiken de mensen als dobber bij het vissen, om water te putten, als soepkom en om rattenvallen van te maken. De rook van het vruchtvlees dat men aangestoken heeft, verdrijft insecten. Wanneer men het met melk vermengt, krijgt men een lekkere yoghurt. Kinderen zuigen of kauwen op baobabzaden. De rode zaden worden op straat als snoep verkocht. Zij smaken een beetje zuur.
De zaden met hun hoog eiwit-en vetgehalte worden met gierst samen tot voedzame gerechten verwerkt.
Vroeger werd het gedroogde vruchtvlees naar Europa geëxporteerd als geneesmiddel (terra lemnia) en gebruikt voor de zeepbereiding.
En natuurlijk is de apebroodboom ook de huisapotheek van het dorp. Voedende moeders geven hun babi’s soms een beetje van het melige vruchtvlees om het kleintje te beschermen tegen buikkrampen, diarree en koorts. Van bijna alle delen van de boom wordt medicijn gemaakt die men op de markten verkoopt: tegen ontstekingen, tandpijn, diarree, griep, astma, nierkwalen, ter bevordering van de bloedsomloop, tegen malaria en ademhalingsproblemen.
Mythologie Adansonia
Hij wordt zeer gewaardeerd, soms gevreesd en soms aanbeden.Volgens een legende wordt iedereen die een bloem van de apebroodboom plukt door een leeuw verslonden. Men gelooft dat in de bloemen geesten wonen. De in water geweekte zaden zouden tegen aanvallen van krokodillen beschermen. Wie een aftreksel van de schors drinkt, wordt groot en sterk.
Volgens een andere legende vroeg de apebroodboom op een dag aan God om hem de mooiste boom van de aarde te maken. God vervulde deze wens. Eerst was de boom daar erg blij, maar dan merkte hij dat zijn schoonheid zich onder de aarde bevond, terwijl zijn wortels omhoog rezen. De boom was verontwaardigd, en God zei: "Ik heb jou tot mooiste van de wereld gemaakt, maar niemand mag het zien behalve jijzelf."