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Indigenous fruits constitute an important part of human diets in many sub-Saharan African countries, particularly in rural areas and during droughts. In order to promote and expand the utilisation of these fruits, knowledge on their nutritional composition is essential. This review presents the results of a literature research of the nutritional composition of ten selected indigenous fruits from sub-Saharan Africa. Species were selected based on their current importance as well as their future potential for nutrition, processing and cash income generation. Compositional data were compiled and mean values of components per species were calculated. Most papers were compiled for Adansonia digitata (26) and Dacryodes edulis (16), followed by Tamarindus indica (ten), Balanites aegyptiaca (nine), Sclerocarya birrea (nine), Ziziphus mauritiana (nine), Vitex doniana (seven) and Irvingia gabonensis (five), and least for Uapaca kirkiana (three) and Syzygium guineense (three). Fruits were found to be mainly analysed for macronutrients and minerals. Vitamins, apart from vitamin C, were rarely reported. Substantial compositional differences were found among as well as within the different fruit species. The results of this study emphasise the need to generate more high-quality data on a wider spectrum of components of the selected indigenous fruits in sub-Saharan Africa.

An in vitro ruminal gas production study was conducted to assess the effect of yeast supplementation on rumen fermentation of tanniniferous tropical browse mixtures prepared by mixing Berchemia discolor with Acacia brevispica, Acacia elatior, Acacia mellifera, Balanites aegyptiaca, Grewia bicolor or Zizyphus mucronata in a 1:1 dry weight ratio. The six browse mixtures were incubated with buffered rumen fluid alone or supplemented with dried Japanese Sake yeast (JSY) or polyethylene glycol (PEG). Ruminal gas production characteristics were evaluated using the Gompertz equation. The JSY addition increased gas production volume (P

After decades of drought in the Sahel, several studies have reported a ‘(re)greening’ of the area. However, most of these studies were based on large scale climatological or remotely sensed observations, with little or no ground truthing. The aim of this study was to assess the local perceptions of the distribution of socio-economically important tree species in the Sub-Sahel of Burkina Faso. Semi-structured interviews were performed with 87 groups of informants from 20 villages belonging to three ethnic groups (Mossi, Fulani and Samo). Univariate and multivariate statistics were used to compare perceptions between the targeted ethnic groups. According to the locals, more than 80 per cent of the 90 listed species were declining, with over 40 per cent identified as threatened, including numerous plants of great economic value. Increasing species were mostly drought-tolerant plants such as Balanites aegyptiaca. A few species were listed as locally extinct. Gender and age did not significantly affect local knowledge, whereas ethnicity did. The major causes of species decline were identified to be drought, deforestation and bushfires. In all ethnic groups, informants observed a southward shift in species distribution. Local perceptions suggest a general decline in woody vegetation. Thus, the alleged (re)greening in the Sahel might not have reversed the degradation of woody species in the area. Data derived from local ecological knowledge were consistent with that of many ecological studies, suggesting the reliability of people's knowledge for obtaining ecological data. Information from this study can be used as baseline for conservation of species identified as threatened. Copyright © 2011 John Wiley & Sons, Ltd.

Summary The aim of the present study is to analyze the structure of the populations of eight common shrubs and trees in Wadi Allaqi Biosphere Reserve (South-East Egypt) through demographic survey of the plants. This study is special important for the populations of trees and shrubs that are continuously subjected to overuses such as cutting, overgrazes and other constraints. For achieving this, 112 stands were selected at 19 locations distributes in the upstream, midstream and downstream parts, including the different Wadi tributaries. The locations and stands were selected to present a wide range of physiographic and environmental variation in each tributary. In each location, sampling stands were situated randomly. For each species in each stand, the height and several crown diameters of each individual depending on its uniformity were measured. The size frequency distributions of Acacia ehrenbergiana, Tamarix nilotica, Salsola imbricata and Leptadenia pyrotechnica populations were either inverse-J-shaped or positively skewed which may represent rapidly growing populations with high reproductive capacity. Such distributions may also indicate a high juvenile mortality. In these populations, the younger individuals are preponderant than the older ones, which is an indication of strength and success of the species, it is mostly due to victorious germination and survival of seedlings. On contrast, the other four species, Acacia tortilis subsp. raddiana, Calotropis procera, Acacia tortilis subsp. tortilis and Balanites aegyptiaca have a tendency towards the J-shaped or negatively skewed distribution. Such distributions characterize the declining population of limited regenerations capacity (the population has higher proportions of large individuals than the smaller ones).

Sahelian savannah faces increasing pressure from human activities, leading to its degradation. The aim of this study was to investigate the possibility of restoration of dryland savannah vegetation by the elimination of disturbance factors on the ecosystem. Is degraded dryland savannah vegetation able to be restored by means of natural succession? What is the timescale for its recovery? The study took place in the Bandia Reserve, 65 km south-east of Dakar (Senegal), a unique site with two successional stages due to the elimination of uncontrolled exploitation. The vegetation structure of 15 years (15YRS) and 5 years (5YRS) after fencing was compared with vegetation exposed to continuous livestock grazing and wood collection outside the fenced area. Calculated by redundancy analysis, a significant effect of selected areas on the cover of all species was revealed and successional stage explained more than 45% of data variability. Perennial forbs, annual forbs and perennial grasses achieved the highest cover in 5YRS, woody species in 15YRS and annual grasses in the area outside of the fenced reserve. The dominant woody species Acacia seyal, A. ataxacantha, A. nilotica subsp. adstringens and Balanites aegyptiaca reconstituted the dense formation of Acacia bushland by means of natural succession in the 15YRS area. Resume La savane sahelienne subit une pression croissante des activites humaines, qui entrainent sa degradation. Le but de cette etude etait d’etudier la possibilite de restaurer la vegetation de la savane seche en eliminant les facteurs de perturbation de l’ecosysteme. La vegetation de savane seche est-elle capable de se retablir par voie de succession naturelle ? Quelle est l’echelle de temps de cette restauration ? Cette etude a eu lieu dans la Reserve de Bandia, situee a 65 km au sud-est de Dakar (Senegal), un site unique qui enclot deux stades de succession en raison de la fin de son exploitation incontrolee. La structure de la vegetation qui s’est developpee quinze ans (15 A) et cinq ans (5 A) apres la pose d’une cloture a ete comparee a la vegetation exposee au pâturage continu du betail et a la collecte de bois, en dehors de la cloture. Une analyse de redondance a revele un effet significatif des zones choisies sur la couverture de toutes les especes, et le stade de succession a permis d’expliquer plus de 45% de la variabilite des donnees. Les dicotyledones perennes et annuelles et les monocotyledones perennes atteignaient la plus grande couverture en 5 A, les especes ligneuses en 15 A, et les monocotyledones annuelles dans la zone situee en dehors de l’aire cloturee. Les especes ligneuses dominantes, Acacia seyal, A. ataxacantha, A. nilotica subsp. adstringens et Balanites aegyptiaca ont reconstitue la formation dense d’une brousse aAcacia par la succession naturelle dans la zone 15 A.

The Sahel region of West Africa is an important wintering ground for Palearctic migrants. It is, however, undergoing significant anthropogenic degradation that is likely to reduce its value in this regard. Despite there being evidence that the populations of several Palearctic species may be determined by conditions on their Sahelian wintering grounds, there are almost no baseline data on their habitat use there and so the effects that habitat change might have on their future density and distribution cannot be determined. This study measured which habitat variables were associated with the presence of Common Whitethroat Sylvia communis, Lesser Whitethroat S. curruca and Subalpine Warbler S. cantillans by carrying out point counts and habitat measurements at 1861 points at 16 sites in northern Nigeria during the winters of 2001 and 2002. Common Whitethroats were most common at intermediate tree heights and densities of Salvadora persica (with this effect strongest in the pre-migratory period), and increased as Balanites aegyptiaca density increased initially, although this effect levelled off at higher Balanites densities. Subalpine Warblers were most common at intermediate tree heights and Balanites densities, increased as Acacia and Salvadora density increased, decreased with tree density and were least common at intermediate shrub densities. Lesser Whitethroats were most common at intermediate tree heights, Acacia and Salvadora densities, increased with Balanites density, and decreased with tree density and diversity. The shallow slopes of the significant relationships found between Palearctic warbler species and habitat parameters suggest that the group may be robust to habitat degradation, with densities remaining relatively constant across a wide range of habitat types. Common Whitethroats, in particular, appear to be able to survive in extremely degraded habitats, yet may be vulnerable to the disappearance of Salvadora, the fruit of which may allow pre-migratory fattening.

Summary Denaturing gradient gel electrophoresis (DGGE) of amplified nifH gene fragments was used to study the diazotrophic community of soil samples under Acacia tortilis ssp. raddiana (legume tree) and Balanites aegyptiaca (non-legume tree), two dominant plant species growing naturally in the dryland part of Senegal. Samples were taken along transects from the stem up to 10 m distance from it, at depths of 0–0.25 m and 0.25–0.50 m. Sampling was done in the dry season (25 June 1999) and in the rainy season (28 August 1999). The community structure and diversity of the bacterial groups from the different samples was analysed further using different techniques, such as statistical analysis and diversity index evaluation of the band patterns. Diazotrophic diversity was lower under B. aegyptiaca than under A. tortilis ssp. raddiana. Multidimensional scaling (MDS) analysis and ANOSIM tests showed a significant effect of the tree on the diazotroph assemblages. SIMPER analysis showed that the major elements responsible for the dissimilarity are a member of the genus Sinorhizobium, which is characteristic of the samples taken under A. tortilis ssp. raddiana and a member of the cluster Bradyrhizobium for the samples taken under B. aegyptiaca. Forty-four major bands were partially sequenced, yielding 33 different nifH sequences, which were used in phylogenetic reconstructions. Most sequences were affiliated with the alpha- beta- and gamma-proteobacteria. Five nifH sequences were identical to those of Pseudomonas stutzeri, and one sequence showed 100% similarity to that of Azotobacter vinelandii. Four bands were affiliated with the Cyanobacteria and a single one with the Firmicutes. For both trees, there were also clear differences between the samples taken in the dry and rainy seasons. Only for the samples taken under A. tortilis ssp. raddiana was a significant difference found between the two sampling depths.

This work examines the effects of lyophilized extracts of the medicinal plants Rhazya stricta, Balanites aegyptiaca and Haplophylum tuberculatum on liver damage induced by paracetamol in mice. Rapid HPLC finger prints for some of these extracts were made. The hepatoprotective effects of the plant extracts were compared with that of the standard hepatoprotective agent silymarin. The extracts (1 g/kg) and silymarin (0.1 g/kg) were given orally for 5 consecutive days .On the last day of treatment a hepatotoxic oral dose of paracetamol (0.6 g/kg) was given, and 3 h later, the hepatic function of mice was evaluated using pentobarbitone -induced sleeping time, the concentration of reduced glutathione (GSH) in liver, and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transferase (GGT) and cholesterol concentration in plasma. The livers were weighed and examined for macro- and microscopic changes. Pretreatment with R. stricta or with silymarin protected the livers of treated mice against paracetamol hepatotoxicity as evidenced by a significant improvement of the above liver function tests. B. Aegyptiaca had a relatively modest hepatoprotective activity, while H. tuberculatum was almost ineffective. Oral pretreatment of mice for 5 consecutive days with an extract of R. stricta or silymarin protected about 57% and 92% of the treated mice, respectively, against the lethal effect of paracetamol (1 g/kg). B. aegyptiaca and H. tuberculatum protected only 27% and 16% of the animals, respectively. Copyright © 2001 John Wiley and Sons, Ltd.

In order to find alternative protein sources in African regions where protein deficiency in nutrition is prevailing, solubility, in-vitro digestibility, amino acid composition and chemical score of Balanites aegyptiaca Del. kernel proteins were investigated as a function of different processing steps including defatting, air classification, wet sieving and aqueous ethanol treatment. Air classification delivered a fine fraction of 58.1% of the total protein. Applying a wet sieving process, a protein concentrate of 72.9% protein content was achieved but the recovery was very low (35.6%). However, in case of isoelectric precipitation followed by aqueous ethanol treatment both protein content (78.2%) and recovery (53.7%) were high. Data concerning the chemical score revealed, that lysine content of the defatted kernel flour amounted to 74.2% of the recommended FAO/WHO standard level. In-vitro protein digestibility was found to be higher than of legume proteins. The digestible protein of the full fat flour, defatted flour, air classified and wet sieved fine fractions and protein concentrate were 91.9, 93.7, 82.(), 86.4 and 94.2%, respectively. The sapogenin content per 100 g protein of the investigated protein preparations was significantly lower (46% to 62%) than of the initial material (oilcake).

Summary Abundances of Phlebotomus orientalis, P. papatasi (Diptera: Psychodidae) and other sandflies were investigated in relation to different types of vegetation associated with endemic foci of visceral leishmaniasis (kala-azar) in eastern Sudan. Sandfly collection sites were in Umsalala Village (Galabat Province) and Dinder National Park (Dinder Province). Sandfly species found in the area were P. orientalis, P. papatasi, Sergentomyia africana, S. antennata, S. clydei, S. schwetzi and S. squamipleuris. Among the types of trees in the Dinder area, P. orientalis was more abundant in forests dominated by Acacia seyal than where Combretum kordofanum, Balanites aegyptiaca, Hyphaena thaibaica or Ziziphus spinachristi were the dominant trees. At Umsalala, P. papatasi was more abundant in the village than at any site with dense vegetation, but P. orientalis was uncommon. Sergentomyia spp. were distributed fairly evenly amongst most types of vegetation investigated at both localities. The ecological distribution of sandflies and epidemiology of kala-azar in Sudan are discussed with emphasis on the association of P. orientalis with A. seyal woodlands.

Summary The Acacia seyal zone and the woodland zone of Waza National Park were sampled by means of line transects to assess damage to trees caused by elephants. In the Acacia seyal zone a total of 1503 trees was examined of which 65% were undamaged, 15% less than three-quarters browsed, and 20% were seriously damaged. Of all trees browsed and trees seriously damaged the majority (50% and 31%, respectively) came from the mature class. It is concluded that elephant damage to Acacia trees is not yet serious but if the trends continue (a doubling of the number of trees killed in 15 years), elephant might have considerable effects on Acacia dynamics and structure. In the woodland zone a total of 1431 trees was examined of which 55% were undamaged, 36% were less than three-quarters damaged and 9% were seriously damaged. Of all trees browsed and trees seriously damaged the majority (66% and 74%, respectively) came from the mature class. The woodland zone of Waza is under far less browsing pressure than that of Kalamaloue National Park, a dry season habitat for some of the Waza elephants. In both parks Acacia seyal, Piliostigma reticulatum, Combretum spp. and Balanites aegyptiaca were sought out as preferred foods. The study concludes with a recommendation for continued monitoring of the vegetation in Waza and Kalamaloue parks so that proper management can be taken to conserve it. It stresses the importance of the hydrological restoration of the Waza–Logone floodplain. Resume Les effets du broutage par les elephants dans la zone aAcacia seyal et la partie arbustive du Parc National de Waza ont eteevalues par echantillonnage sur des transects arm d'evaluer les degâts causes aux arbres. Dans la zone aAcacia seyal un total de 1503 arbres furent examines dont 65%etaient indemnes, 15% endommages a moins de trois-quarts et 20% serieusement endommages. Parmi les arbres broutes et les arbres serieusement endommages la majorite (50% et 31% respectivement) appartenait a la classe des adultes. Il est conclu que les degâts causes par les elephants ne sont pas encore graves mais que si la tendance se poursuit (doublement en 15 ans des arbre serieusement endommages), les elephants pourraient avoir des effets considerables sur la dynamique et la structure des Acacia. Dans la partie arbustive un total de 1431 arbres furent examines dont 55%etaient indemnes, 36% endommages a moins de trois-quarts et 9% serieusement endommages. Parmi les arbres broutes et les arbres serieusement endommages la majorite (66% et 74% respectivement) appartenait a la classe des adultes. La partie arbustive de Waza subit une pression bien moins importante que celle du Parc National de Kalamaloue, un habitat de saison seche pour les elephants de Waza. Dans les deux parcs, Acacia seyal, Piliostigma reticulatum, Combreturn spp., and Balanites aegyptiaca sont les nourritures preferees. Cette recherche se termine en recommendant de poursuivre les observations sur la vegetation des parcs de Waza et Kalamaloue de facon a entreprendre une gestion correcte pour la proteger. Elle insiste sur l'importance de la restauration du systeme hydrologique de la plaine d'inondation de Waza–Lagone.

Balanites aegyptiaca (L) Del. has a trizonate ovule primordium and an elongated bitegmic, crassinucellate and anatropous ovule. The dermal inner and outer integument are about 45-layered and the inner layer of the inner integument becomes slightly endothelial. After fertilization the nucellus and subsequently the inner integument are resorbed. The outer integument ultimately becomes about 30-layered. The cells of the inner layer of the outer integument divide once periclinally. The vascularized seed-coat consists of parenchyma cells with scattered, lignified sclerenchyma elements. Ovule and seed characters support the recognition of a separate family Balanitaceae and a relationship with an enlarged order Linales

The aqueous extract of Balanites aegyptiaca bark, which is used in Sudanese folk medicine in the treatment of jaundice, was without effect when studied on rabbit intestine, rabbit aortic strip, rat stomach strip, rat uterus and rat phrenic nerve-diaphragm in a dose up to 10 mg/mL gut bath. In a larger dose (25 mg) the extract decreased significantly the contractility and the rate of the isolated perfused rabbit heart. Administration of the aqueous extract to biliary duct-ligated rats, showed a dose-dependent significant decrease in serum bilirubin level. The chronic and subchronic toxicity investigations indicate the safety of the aqueous extract at a dose level which showed a significant decrease in serum bilirubin level in experimental obstructive jaundice in rats.

A new long chain aliphatic compound, 10-methyl-n-heptacosane and a new sugar, diglucosyldirhamnoside have been isolated from the ethanolic extract of the stem bark of Balanites aegyptiaca. The structures of these compounds were elucidated by a combination of spectral methods (IR, MS, 1 H and 13 C NMR).

The effects of daily oral feeding of a crude alcohol extract from the pericarp of unripe fruits of Balanites roxburghii at a dose of 500 mg/kg for 45 days were investigated with respect to epididymal and testicular histophysiology, metabolism and the fertility potential of mice, following withdrawal study. The testicular and cauda epididymal parameters revealed altered physiology and metabolism resulting in a reduction in fertility of extract-fed mice. Moreover, the induced effects seemed to be transient and were reversible upon withdrawal, showing its antifertility action.

The anthelmintic activity of aqueous extracts (0.25 mg/mL) from 14 plant species that represent seven families of the Sudanese flora was examined using the free living rhavditid nematode, Caenorhabditis elegans as a test organism. Extracts of Balanites aegyptiaca and Sesbania sesban were the most effective (LC 50 , 0.8 an,d 8.0 mg/mL, respectively). Extracts of Albizzia anthelmintica, Cympopogen narvatus, Abrus precatorius, Rhyncosia minima, Striga hermonthica and Anogeissus leiocarpa (LC 50 , 9.5-84.6 mg/ml were less effective in this model test system. Extracts of six plant species, Albizzia malacophylla, Gardenia lutea, Physostigma mesoponticum, Salvadora persica, Xeromphis nilotica and Waltheria indica had no effect upon C. elegans survival

Saponins and sapogenins isolated from Balanites roxburghii, Agave cantala and Phaseolus vulgaris were studied for insect antifeedant activity against the larvae of the noctuid, Spilosoma obliqua (Walker). The most active compound was diosgenin-3-0-[α-L-rhamnopyranosyl (12)]-[β-D-glucopyranosyl (13)-β-D-glucopyranosyl (14)]-β-D-glucopyranoside (X), inhibiting approximately. 73.63 per cent feeding at 0.02 per cent concentration. Relative efficacy of all the tested compounds was assessed, using azadirachtin as standard.

Five new steroidal glycosides were isolated from the roots of Balanites aegyptiaca, a widely used African medicinal plant. On the basis of spectroscopic and chemical evidence, their structures were determined as (3β,12α,14β,16β)-12-hydroxycholest-5-ene-3,16-diyl bis(β-D-glucopyranoside) (1), (3β,20S,22R,25R)- and (3β,20S,22R,25S)-26-(β-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl β-D-xylopyranosyl-(13)-β-D-glucopyranosyl-(14)[α-L-rhamnopyranosyl-(12)]-β-D-glucopyranoside (2 and 3, resp.), and (3β,20S,22R,25R)- and (3β,20S,22R,25S)-spirost-5-en-3-yl β-D-xylopyranosyl-(13)-β-D-glucopyranosyl-(14)[α-L-rhamnopyranosyl-(12)]-β-D-glucopyranoside (4 and 5, resp.)

Two samples of Balanites aegyptiaca fruits were collected from two different regions in Sudan. The edible mesocarp contained 1.2–1.5% protein and 35–37% total sugars of which 81.3–91.1% is present as reducing sugars. The kernels contained 45.0–46.1% oil. Palmitic, stearic, oleic and linoleic acids were the main fatty acids. The ratio of saturated to unsaturated fatty acids was 10:26 in both samples. The protein was found to be low in aromatic amino acids.

Lalob fruit from the Sudan has been examined by modern chemical and physical methods. The kernels which amount to 9 to 10% of the fruit contain approximately 46% oil. Extraction of the ground kernels with commercial hexane yields a light yellow oil, having a composition calculated from iodine-thiocyanogen values corresponding to 43.8% linolein, 30.5% olein, 23.7% saturated acid glycerides, and 2.0% unsaponifiable matter. Calculation of the composition from ultraviolet absorption measurements gave results in fairly close agreement with those obtained by the iodine-thiocyanogen method. It was shown that the color of the crude oil was due almost entirely to the presence ofa-carotene.