African Fruit Research Articles

Physicochemical properties of South African prickly pear fruit and peel: Extraction and characterisation of pectin from the peel

Abstract The aim of this study was to determine the physicochemical properties, extract and characterise pectin from green (Morado), purple (Algerian), and orange (Gymno carpo) varieties of South African prickly pear (PP) (Opuntia ficus-indica) fruit peel. Pectin was extracted using sulphuric acid at four different pH levels (1, 2, 3, and 4) and three different microwave power levels (low 300 W, medium 400 W, and high 500 W) at a fixed time of 10 min. Yield of pectin for purple ranged from 2.9 to 13.8%, orange from 1.4 to 9.8%, and from 2.3 to 10.0% for green prickly pear peel (PPP). Maximum yield of 13.8% on purple, 10.0% on green, and 9.8% on orange was obtained at pH 1.0 and medium power level. Ash content of the extracted pectin was significantly high at 25.16, 34.26, and 36.30% for green, orange and purple PPP, respectively. However, pectin showed lower moisture content and equivalent weight. The methoxyl contents were 2.28, 2.38, and 3.86%, for anhydrouronic acid contents were 25.58, 25.93, and 38.84%, and degree of esterification was 49.87, 50.63, and 56.39% across the orange, purple, and green varieties. The PPP pectin spectra exhibited similarities in their absorption pattern to that of commercial citrus pectin.

Oviposition responses of Bactrocera dorsalis and Ceratitis cosyra to Dufour’s and poison gland extracts of Oecophylla longinoda (Hymenoptera: Formicidae)

The predatory African weaver ant, Oecophylla longinoda (Hymenoptera: Formicidae) effectively control pests by predation as well as by semiochemicals which influence the behaviour of certain species. Here, we investigated and compared the role of O. longinoda semiochemicals on the oviposition responses of two major fruit fly (Diptera: Tephritidae) species of mango; the invasive species, Bactrocera dorsalis, endemic to Southeast Asia and the African native species, Ceratitis cosyra. We carried oviposition choice assays with ant-exposed and unexposed mangoes, using extracts of ant whole body and body parts. Our results show that the flies avoided and laid fewer eggs on weaver ant-exposed than unexposed mango peel discs. Subsequent assays with mango discs treated with whole body extracts in hexane, ethyl acetate, methanol and water reduced oviposition responses in C. cosyra. Moreover, discs treated with abdominal extracts in hexane and water reduced egg laying in B. dorsalis. whereas hexane, methanol and water extracts of the abdomen reduced oviposition in C. cosyra. Additionally, mango discs treated with extracts of exercised Dufour’s and poison gland in hexane elicited stronger oviposition reduction responses in C. cosyra than in B. dorsalis. These results suggest that ant gland compounds play a role in the oviposition avoidance behaviour of both fruit fly species. Moreover, both African fruit fly species and invasive Asian species, are repelled by Oecophylla longinoda semiochemicals implying that B. dorsalis experienced similar evolutionary pressures, and reacting to similar cues, from Oecophylla smaragdina in Asia as did C. cosyra from Oecophylla longinoda in Africa.

Metabolome-based profiling of African baobab fruit (Adansonia digitata L.) using a multiplex approach of MS and NMR techniques in relation to its biological activity.

Adansonia digitata L. also known as African baobab is one of the most important fruit-producing trees, widely distributed in the African continent. Baobab fruits are known to possess potential health benefits and nutritional value. This study aimed to holistically dissect the metabolome of A. digitata fruits using a novel comparative protocol using three different analytical platforms. Ultra high performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS/MS), and headspace solid-phase microextraction/gas chromatography coupled to mass spectrometry (HS-SPME/GC-MS) were respectively employed for phytonutrients and aroma profiling, whereas GC-MS post silylation provided an overview of nutrients i.e., sugars. UHPLC-HRMS/MS analysis allowed for the assignment of 77 metabolites, among which 50% are reported for the first time in the fruit. While GC-MS of silylated and aroma compounds led to the identification of 74 and 16 compounds, respectively. Finally, NMR-based metabolite fingerprinting permitted the quantification of the major metabolites for future standardization. In parallel, in vivo antidiabetic potential of the baobab fruit using a streptozotocin (STZ) induced diabetic rat model was assessed. Histopathological and immune-histochemical investigations revealed hepatoprotective and renoprotective effects of A. digitata fruit along with mitigation against diabetes complications. Moreover, the administration of A. digitata fruits (150 mg kg−1) twice a week lowered fasting blood glucose levels.

Growth performance and nutrient digestibility of weaner rabbits fed African locust bean (Parkia biglobosa) fruit pulp

The need to seek for alternative feed materials to replace maize as source of energy to support growth in weaner rabbits necessitated this study. A feeding trial of 84 days using unsexed rabbit crosses (New Zealand white and Chinchilla) was conducted to assess the replacement value of African Locust bean fruit pulp for maize in weaner rabbits diet. Five diets were formulated, such that 100% maize and 0.00% fruit pulp of African fruit pulp at (T1), 75% maize and 25% inclusion of African locust bean at (T2), 50% maize and 50% African locust bean pulp as (T3), 25% maize and 75% African fruit pulp at (T4) while (T5) contain 100% fruit pulp of African locust bean and 0.00% maize, respectively. Seventy-five (75) weaner rabbits with average initial weight between 610.67g - 622.60g were randomly allocated in a complete randomized design (CRD) experiment to the five diets with fifteen (15) weaner rabbits in each treatment which were subdivided into three (3) replicates having five (5) weaner rabbits in each replicate. The weaner rabbits were housed in individual cage compartment. Data collected were subjected to one-way analysis of variance (ANOVA). Proximate and Phytochemical composition of sun dried fruit pulp of African locust bean used in the diets showed dry matter content of 91.38 %, crude protein 6.70 %, crude fiber 11.21 % Ether extract 5.04 %, ash 5.02 and nitrogen free extract 63.41 %. The metabolizable energy contained in the ingredient was 3079.41 ME/Kcal/Kg. Proximate composition of the experimental diets fed to weaner rabbits carried out indicated that T1 had dry matter content of 93.28 %, crude protein of 19.80 % and 12.41 % of crude fiber. Ether extract was higher in T5 with 8.48 %, while nitrogen free extract contained in T3 had the highest value of 51.17 %. However, ash content in T5 has the highest value of 7.83 %. The metabolizable energy in all the dietary treatment shows that T5 had the highest value of 3013.21 ME/Kcal/Kg. Nutrient digestibility in weaner rabbits showed crude protein digested during the experimental work in the treatment ranged from 69.46 % to 73.73 %. Crude fiber digested was between the ranges of 42.20 % to 58.12 % in all the treatments. Ash content ranged from 50.18 % to 56.35. T5 has the highest percent nutrient of ether extract digested with 83.36 % while the lowest value was obtained in T1 with 58.99 respectively. Values in nitrogen free extract ranged from 65.20 % to 72.43 % and showed a significance difference (P< 0.05) in all the treatment. Data were collected on daily feed intake and weekly weight. Feed conversion ratio, protein efficiency ratio, energy efficiency ratio, nutrient digestibility and feed cost benefit N (kg) were calculated. Weaner rabbits fed 75% maize and 25% African fruit pulp (T2) consumed more feed and significantly gained more weight (P < 0.05) than those fed the other diets. Feed conversion, protein efficiency ratio and energy efficiency ratio were not significantly (P>.0.05) influenced by the treatment diets while nutrient digestibility showed a significance difference (P < 0.05) in all the treatments. Average feed cost/weight gain of production with maize was estimated at N311.25 in T1 while the African locust bean fruit pulp was N161.81 in T5, a cost difference of N149.44, this resulted to a progressive reduction in the cost treatment of feed with increase in the level of fruit pulp of African locust bean meal. The results of this study indicated that when 25 % fruit pulp of African locust replaced maize, the rabbits performed better than the control diet and also of more economical option.

Evaluation of African Star Apple (Chrysophyllum albidum) Seed Oil as a Potential Feedstock for Industrial Application

Aims: Evaluate possible application of African Star Apple seed oil as industrial raw material geared towards possible conversion of waste to wealth with no negative impact as it borders on food scarcity. Also unveiling the possibility of a sustainable environment via the eradication of waste from the environment, thereby creating a clean environment.
 Place and Duration of Study: Fresh ripped fruits of African Star Apple were bought from some local market sellers at Agbarha-Otor market which is located in Ughelli North Local Government Area of Delta State, Nigeria on longitude 6° 2' 54" E /5° 30' 40" N, between November, 2019 and March, 2020.
 Experimental Details: Soxhlet extraction with n-hexane as solvent was used for the oil extraction of 100 g per batch of extraction. Pretreatment procedure of oil was done prior to transesterification. Homogenous base-catalyzed transesterification reaction was used in this study under controlled experimental conditions such as temperature, reaction time, methanol to oil molar ratio and catalyst type and concentration were examined under varied ranges to ascertain optimum experimental conditions for the reaction. Extracted seeds oil were analysed for its physicochemical properties using standard methods via: specific gravity, acid value, refractive index, saponification value, iodine value and free fatty acid using standard methods.
 Results: The results showed an oil yield of 14.9%, an indication that the seed reflects a poor source of abundant oil. Results obtained for the physiochemical properties, revealed that; specific gravity, refractive index, saponification value, acid value, free fatty acid and iodine value showed values of 0.896 kg/m3, 1.549, 231.32 mgKOH/g, 3.23 mgKOH/g, 2.07% and 47.63 mg/100 g respectively. Also, results for Methanol: Oil ratio showed that maximum yield was obtained at 6:1 molar ratio. Maximum conversion efficiency for molar concentration was achieved at 0.75% for both catalysts. While a reaction time of 125 min projected better yield.
 Conclusion: The seed of African star fruit are discarded as waste, therefore its use as a source of oil for industrial feedstock and other domestic application, poses no challenge with regards to food security. Its non-drying potential based on its low iodine value, makes it suitable lubricating oil for industrial application. Similarly, potential application of the oil as feedstock for the production of biodiesel is justified on the basis of its low acid value. Conclusively, the seeds may not have sufficient oil volume potential to be used as edible (domestic) and industrial oil. Consequently upon its low yield, application for biofuel production in commercial scale becomes unrealistic.

The effects of moisture content, fiber length and compaction time on African oil palm empty fruit bunches briquette quality parameters

In this paper a study on the process of densification of oil palm empty fruit bunches (OPEFB) is presented. An empirical-statistical model that allows the evaluation of densification process is obtained through an experimental factorial design. The main purpose of the experimental arrangement is to find the appropriate reference values for the experimental factors - moisture content, fiber length and compaction time-with which optimal performance responses of briquettes are achieved. Statistical models are obtained that explain in an acceptable way the influence of independent experimental factors on the mechanical properties of briquettes, such as briquettes density, durability index and compressive strength. It is possible to conclude that briquettes manufactured with the appropriate reference values, moisture content of 8% w.b., fiber length of 73.6 mm and a compaction time of 26.6 s respectively, meet mechanical and thermal requirements that are required in the most representative standards for biomass briquettes for energy purposes. Results obtained in the current investigation can be used as reference for the design of an industrial pilot plant destined to the densification of EFB of African oil palm.

Light and Electron Microscopic Studies of the Seminal Vesicular Glands of the African Straw-coloured Fruit Bat, Eidolon helvum

Background: Secretions from the seminal vesicular gland enhance the survival and reproductive functions of the spermatozoa. The order Chiroptera has evolved great diversity in their reproductive structure influenced by location, abiotic factors and availability of food. Eidolon helvum is a near threatened tropical African fruit bat and little is known of its reproductive biology. The aim of this study was to highlight the structure, histochemistry and ultrastructure of the seminal vesicular glands of Eidolon helvum. Methods: The paired seminal vesicular glands of 16 adult male Eidolon helvum were obtained in May during the early rainy season in tropical Nigeria. The glands were evaluated grossly, histological and ultrastructurally.Result: The spirally coiled tubular organs were divided into numerous lobules of tubular-alveolar glandular acini lined by simple cuboidal epithelium made up of basal cells and mono or bi-nucleated cuboidal secretory cells. PAS positive secretions projected from the apical surfaces. Principal secretory cells contained numerous rough endoplasmic reticulum, mitochondria, Golgi complexes, electron lucid secretory vesicles, electron dense granules and lysosomes. The unique merocrine and apocrine secretions contributed to the formation of vaginal plugs.

Physicochemical Properties and Fatty Acid Profile of African Elemi Fruit Pulp Oil Compared with Palm Kernel Oil

African elemi (Canarium schweinfurthii) fruit pulp oil was extracted and refined which yielded 39.5% oil. It was characterized for its physical, chemical, phytochemical properties and fatty acid profile in comparison with palm kernel oil (PKO). The result for physical properties revealed that there was no significant difference in the density, refractive index, and flash point of the oils. African elemi fruit pulp oil (AEO) had significantly (p>0.05) higher slip melting point and viscosity while significantly (p<0.05) lower smoke point and fire point. Chemical properties of the oils such as iodine, acid value, unsaponifiable matter and free fatty acids were significantly (p>0.05) higher in AEO with the values of 76.79 g/100 g, 0.94 mg KOH/g, 1.32 and 0.58%, respectively and significantly (p<0.05) lower in saponification and peroxide values, 155.47 mg KOH/g and 1.06 meq/kg, respectively compared to the values obtained for the PKO. Saturated fatty acid profile of AEO had the values of 9.44, 32.24 and 2.63% for myristic (C14:0), stearic acid (C18:0) and palmitic acid (C16:0) while PKO had the values of 48.00, 16.20, 2.50 and 8.40% for lauric (C12:0), myristic (C14:0), stearic acid (C18:0) and palmitic acid (C16:0), respectively. The monounsaturated fatty acids were oleic acid (C18:1) 30.24% for AEO and 15.0% for PKO making oleic acid the highest occurring monounsaturated fatty acids present in AEO. Thus, lauric acid (C12:0) and linoleic (C18:2) was not dictated in AEO while gadoleic (C20:1) was not dictated in PKO. Flavonoids, tannins, saponins, phytates and alkaloids had the values of 0.29, 0.33, 0.13, 0.13 and 0.74% for AEO and 0.32, 0.12, 0.24, 0.11 and 0.07% for PKO, respectively and all were within the acceptable limit of 3% for food products with respect to the phytochemical properties of the oils. The result for solid fat content - temperature profile revealed that PKO and AEO completely melted at 35 °C and 45 °C, respectively.

Phenotypic variation, functional traits repeatability and core collection inference in Synsepalum dulcificum (Schumach & Thonn.) Daniell reveals the Dahomey Gap as a centre of diversity

The miracle plant Synsepalum dulcificum is a multipurpose natural sweetener and a promising West African orphan fruit shrub candidate for genetic improvement. Unfortunately, basic knowledge such as phenotypic variation and inheritance estimates required for implementing a breeding program are still lacking. A set of 203 accessions were sampled in two habitats from seven populations spread across the Dahomey Gap (DG) and the Upper Guinea forest (UG) in West Africa. The phenotypic diversity and allometric relationships among functional traits were analysed; the broad-sense heritability was estimated for fruit-traits, and a mini-core collection was developed in the species. Quantitative variation in tree- and fruit-traits was recorded, and multivariate analyses were performed to assess relationships among accessions, whereas heritability was estimated using the coefficient of repeatability. Tree-traits observed in S. dulcificum were more variable than fruit-traits. While habitat-type only affected tree-traits, the provenance population significantly affected both fruit- and tree-traits, with the UG populations outperforming the DG ones. Significant correlations were observed among fruit-traits on one hand, and among tree-traits on the other hand, whereas poor correlations were observed between tree- and fruit-traits. The multivariate analysis grouped accessions in three clusters. Promising individuals for high fruit mass and pulp-dense genotypes’ selection were identified within clusters. Repeatability estimates for fruit-traits ranged from 0.015 (edible ratio) to 0.88 (fruit mass). The Core Hunter algorithm enabled the extraction of 41 individuals as robust representatives of the initial set of 203 accessions, and the mapping of this core collection suggested Dahomey Gap as a centre of diversity of the species. These original findings offer opportunities, not only for the genetic improvement of S. dulcificum, but also for targeted ex-situ conservation in the species.

Achimota Pararubulavirus 3: A New Bat-Derived Paramyxovirus of the Genus Pararubulavirus.

Bats are an important source of viral zoonoses, including paramyxoviruses. The paramyxoviral Pararubulavirus genus contains viruses mostly derived from bats that are common, diverse, distributed throughout the Old World, and known to be zoonotic. Here, we describe a new member of the genus Achimota pararubulavirus 3 (AchPV3) and its isolation from the urine of African straw-coloured fruit bats on primary bat kidneys cells. We sequenced and analysed the genome of AchPV3 relative to other Paramyxoviridae, revealing it to be similar to known pararubulaviruses. Phylogenetic analysis of AchPV3 revealed the failure of molecular detection in the urine sample from which AchPV3 was derived and an attachment protein most closely related with AchPV2—a pararubulavirus known to cause cross-species transmission. Together these findings add to the picture of pararubulaviruses, their sources, and variable zoonotic potential, which is key to our understanding of host restriction and spillover of bat-derived paramyxoviruses. AchPV3 represents a novel candidate zoonosis and an important tool for further study.

GENETIC VARIABILITY AND INTERRELATIONSHIP AMONG MORPHOLOGICAL TRAITS IN AFRICAN PEAR FRUIT (DACRYODES EDULIS (G.DON) H.J. LAM) ACCESSIONS

African pear fruit (Dacryodes edulis) is a highly sought for multipurpose agroforestry tree species that has the potential for both local and international trades, Nigeria is among the leading producer of the fruit, but its pattern and extent of its genetic variability is currently unknown. Hence, a study was carried out to determine the pattern and extent of genetic variability and interrelationships among 13 morphological traits of African pear fruit accessions. The experiment was laid in a Completely Randomized Design in 5 replications. Data collected on number of leaf production, leaf length, leaf breadth, leaf length/breadth ratio, internode distances, plant height, collar diameter, fresh leaf weight, fresh stem weight, fresh root weight, dry leaf weight, dry stem weight, dry root weight and biomass accumulation were subjected to Analysis of Variance. Treatment means were separated using Duncan’s Multiple Range Test at 5% probability level. Results showed significant (p<0.05) differences among the D. edulis genotypes for most of the traits evaluated indicated variation in the performance of the genotypes and pattern of clustering indicated that there was no association between eco-geographical distribution of genotypes and genetic diversity. PCA revealed that fourteen axes accounted for 100% of the variations observed while the first five axes contributed 73.23% of the total variation observed. The first axis accounted for 25.61% of the total variation while the second and third accounted for 15.43 and 15.01%, respectively. The fourth axis contributed 9.82% of the total variation while the fifth axis contributed 7.36% of the total variation. Significant phenotypic and genotypic correlations were observed between most of the plant characters evaluated and biomass accumulation which is an indication that the phenotypic association will be a good index for the genotypic association.

Storage temperature and time changes of phenolic compounds and antioxidant properties of Natal plum (Carissa macrocarpa)

Natal plum is a South African indigenous fruit. Natal plum were stored at 2, 4, 10 and 25 °C (control) temperatures up to 12 days, and fruit were evaluated at 4 day intervals for changes in quality and phenolic compounds. The results showed that 2 °C significantly reduced the weight loss and total colour difference while maintaining the quality attributes. Supervised Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) and the ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometer and chemometric approach separated the fruit stored at low temperature from those stored at 25 °C, and a unique marker compound quinic acid was identified with the low temperature fruit. Similarly, cyanidin (aglycone) separated the fruit stored at 2 °C from those stored at other lower temperatures (4, and 10 °C). Thus, it can be proposed that the temperature stress at 2 °C had favoured the cold-induced accumulation of cyanidin derivatives (anthocyanins) to provide chilling tolerance. The bioactive compounds (cyanidin-3-O-pyranoside (10.4 mg kg−1), cyanidin-3-O-glucoside (54 mg kg−1), and quercetin 3-O-rhamnosyl glucoside (57 mg kg−1)] and the antioxidant activity (FRAP assay) were significantly higher in fruit stored at 2 °C for 12 days. Thus, storage of Natal plum at 2 °C for 12 days can be recommended if the fruit are used as a functional ingredient.

Histology, ultrastructure, and seasonal variations in the bulbourethral gland of the African straw-colored fruit bat Eidolon helvum.

We studied the morphological characteristics and seasonal changes of the bulbourethral gland of Eidolon helvum in a typical African tropical environment. Forty-eight bulbourethral glands were examined using gross anatomical, histological, histochemical, and ultrastructural techniques during the early rainy, late rainy, and peak dry seasons. The pear-shaped bilateral bulbourethral glands were located extra-abdominally in the inguinal region. Trabeculae from the capsule divided the parenchyma into numerous lobules of tubuloalveolar glandular acini. The mucosa was covered by a simple columnar epithelium consisting up of principal secretory cells, columnar dense cells and basal cells, which were progressively pronounced during the dry season. The principal cells contained eosinophilic granules, which were PAS positive while the dense cells did not show affinity for the stains. The mean gross weights, acini diameters, and epithelial heights were greater during the rainy season than the dry season. Ultrastructural evaluation showed that the cytoplasm of the principal cells contained well-developed Golgi complexes, rough endoplasmic reticulum, mitochondria, and secretory vesicles of varying electron densities and sizes. The secretory vesicles were numerous during the early rainy season, decreased during the late rainy season and were scanty during the peak dry season. The simple columnar epithelium observed during the rainy season was replaced by an undefined stratified epithelium during the dry season, and this was associated with cellular degenerations and regenerations. In conclusion, E. helvum has a typical mammalian bulbourethral gland, with a unique cell type, the dense cell whose functions are not well-understood. The gland exhibits cyclical seasonal variation in structure and secretory activity; being active during the early rainy season (breeding season), and showing the lowest activity during the dry season (non-breeding season). Glandular epithelial cell renewal occurs during the dry season in preparation for the next breeding season.

Starch composition, glycemic indices, antioxidant properties and carbohydrate hydrolyzing enzymes activities of African star apple fruit parts

BackgroundAfrican star apple (Chrysophyllum albidum) is a traditonal fruit, which is predominant in tropical regions with the fruit parts consumed by the populace and used in folklore to manage diabetes. However, the likely activity mechanism is still undetermined. The current study examined and compared the inhibitory abilities of African star apple fruit parts on selected key enzymes related to diabetes mellitus in the pancreas tissue of rat.MethodsInhibitory effect of aqueous extract (1:10 w/v) of African star apple fruit parts (pulp, cotyledon, seed coat and pulp coat) on the activities of α-amylase, α-glucosidase, as well as their starch composition, phenolic constituents, estimated glycemic index, and antioxidant properties were assessed.ResultsThe fruit parts showed low sugar, eGI, amylose, and amylopectin contents. The analysis also showed that the fruit parts inhibited α-glucosidase and α-amylase activities and exhibited antioxidant properties. Furthermore, the fruit parts contain high concentrations of beta-amyrin acetate, eleagine, epicatechin, epigallocatechin, skatole, stigmasterol and tetrahydro − 2- methylharman as revealed by HPLC-DAD.ConclusionThe fruit part low estimated glycemic indices, strong antioxidant properties, inhibition of α-amylase and α-glucosidase activities exhibited might be related to the bioactive compounds contained in the extract. This could also be a potential mechanism for the use in the prevention and management of type-2 diabetes. Nevertheless, the African star apple pulp coat displayed the highest property in comparison to other parts of the fruit.

Fruit bats in flight: a look into the movements of the ecologically important Eidolon helvum in Tanzania

BackgroundMany ecologically important plants are pollinated or have their seeds dispersed by fruit bats, including the widely distributed African straw-colored fruit bats (Eidolon helvum). Their ability to fly long distances makes them essential for connecting plant populations across fragmented landscapes. While bats have been implicated as a reservoir of infectious diseases, their role in disease transmission to humans is not well understood. In this pilot study, we tracked E. helvum to shed light on their movement patterns in Tanzania and possible contact with other species.MethodsTracking devices were deployed on 25 bats captured in the Morogoro Municipal and Kilombero District area near the Udzungwa Mountains of Tanzania. Nightly flight patterns, areas corresponding to foraging bouts and feeding roosts, and new day roosts were determined from bat movement data and characterized according to their proximity to urban built-up and protected areas. Sites for additional environmental surveillance using camera traps were identified via tracking data to determine species coming in contact with fruits discarded by bats.ResultsTracking data revealed variability between individual bat movements and a fidelity to foraging areas. Bats were tracked from one to six nights, with a mean cumulative nightly flight distance of 26.14 km (min: 0.33, max: 97.57) based on data from high-resolution GPS tags. While the majority of their foraging locations were in or near urban areas, bats also foraged in protected areas, of which the Udzungwa Mountains National Park was the most frequented. Camera traps in fruit orchards frequented by tracked bats showed the presence of multiple species of wildlife, with vervet monkeys (Chlorocebus pygerythrus) observed as directly handling and eating fruit discarded by bats.ConclusionsBecause we observed multiple interactions of animals with fruits discarded by bats, specifically with vervet monkeys, the possibility of disease spillover risk exists via this indirect pathway. With flight distances of up to 97 km, however, the role of E. helvum in the seed dispersal of plants across both protected and urban built-up areas in Tanzania may be even more important, especially by helping connect increasingly fragmented landscapes during this Anthropocene epoch.

Caractérisation phénotypique des plantules de quatre populations de Sclerocarya birrea (A. Rich.) Hochst. au Burkina Faso

Sclerocarya birrea (A. Rich.) Hochst. est un fruitier oléagineux d’Afrique. Les fortes mortalités après plantation sont dues à l’affectation inappropriée des plants dans les zones écologiques. La caractérisation phénotypique des plantules a pour objectif de déterminer dès le jeune âge des caractères d’adaptation aux conditions écologiques. L’étude porte sur 494 plantules originaires des populations de You, Yarci, Gonsé et Diapangou-Peulh au Burkina Faso. Celles-ci appartiennent à quatre localités circonscrites dans trois zones climatiques. Les résultats montrent que la levée groupée assure la présence de générations chevauchantes à l’intérieur des populations. L’analyse de variance qui fait apparaître des différences intra- et inter-population sur la majorité des variables traduit la diversité phénotypique des plantules. L’analyse en composantes principales montre des caractéristiques spécifiques à chaque population. Le dendrogramme de la classification ascendante hiérarchisée permet d’identifier trois groupes : G1 : Gonsé (55,88 %), Yarci (23,52 %) et You (20,58 %) ; G2 : You (46,15 %), Yarci (42,30 %), Diapangou-Peulh (7,69 %) et Gonsé (3,84 %) ; G3 : Diapangou-Peulh (90 %), Yarci (5 %) et You (5 %). Ces trois groupes traduisent le rapprochement phénotypique entre individus. Ces résultats mettent en évidence l’existence des gains génétiques pour la sélection individuelle et populationnelle. Ils montrent également que ces populations ne sont pas menacées d’impasse évolutive à court terme. L’étude des héritabilités indique que les caractères les plus héritables sont la hauteur de la tige (28,31 %), la longueur de la racine principale (44,30 %), le nombre de racines secondaires (81,89 %), le poids frais des racines (73,47 %) et le poids sec des racines (28,86 %). L’architecture du système racinaire traduit la capacité d’adaptation de Sclerocarya birrea à différents types de sols. Compte tenu de ces résultats, la sélection sur les caractères adaptatifs au jeune âge peut être envisagée.

Underutilized African indigenous fruit trees and food–nutrition security: Opportunities, challenges, and prospects

AbstractThe diverse range of indigenous fruit trees in Africa is a source of untapped potential for food and nutrition security. Here, we review information on 10 indigenous fruit trees that are considered to be underutilized and explore their occurrence, distribution, nutritional components, phytochemicals, and medicinal potentials, as well as their associated challenges and prospects. The indigenous fruit trees, which occur across different ecological zones in Africa, are rich sources of vitamins, minerals, protein, and valuable phytochemicals. They also have recognized medicinal value and used as diverse therapeutic remedies by many ethnic groups in Africa. The key challenges to fruit tree sustainability include indiscriminate and illegal logging, low accessibility, and low acceptability, as well as inadequate research on their cultivation. We proposed a scheme to increase the value chain of underutilized fruit trees, which can contribute to the livelihoods of smallholder farmers and other stakeholders mainly through income generation. In addition to the concerted efforts of multidisciplinary research teams encompassing plant breeders, botanists, molecular biologists, food scientists, and horticulturists, there is an urgent need for governments and other international stakeholders to provide incentives and encourage the domestication, commercialization, and agro‐processing of underutilized fruit trees for future economic prosperity of Africa.

Foraging movements are density-independent among straw-coloured fruit bats.

Intraspecific competition in large aggregations of animals should generate density-dependent effects on foraging patterns. To test how large differences in colony size affect foraging movements, we tracked seasonal movements of the African straw-coloured fruit bat (Eidolon helvum) from four colonies that range from 4000 up to 10 million animals. Contrary to initial predictions, we found that mean distance flown per night (9–99 km), number of nightly foraging sites (2–3) and foraging and commuting times were largely independent of colony size. Bats showed classic central-place foraging and typically returned to the same day roost each night. However, roost switching was evident among individuals in three of the four colonies especially towards the onset of migration. The relatively consistent foraging patterns across seasons and colonies indicate that these bats seek out roosts close to highly productive landscapes. Once foraging effort starts to increase due to local resource depletion they migrate to landscapes with seasonally increasing resources. This minimizes high intraspecific competition and may help to explain why long-distance migration, otherwise rare in bats, evolved in this highly gregarious species.

Phylogeny of African fruit bats (Chiroptera, Pteropodidae) based on complete mitochondrial genomes

Phylogeny of African fruit bats (Chiroptera, Pteropodidae) based on complete mitochondrial genomes

New microsatellite markers for Dacryodes edulis (Burseraceae), an indigenous fruit tree species from Central Africa.

Microsatellites were designed and characterized in the African fruit tree species Dacryodes edulis (Burseraceae). The fruits are commercialized throughout Central Africa and the species is present in forested environments as well as cultivated systems. The high variability of these markers makes them suitable to investigate the structure of genetic diversity in this important food tree species from Central Africa. From a genomic library obtained by next-generation sequencing, 21 new polymorphic microsatellite loci were developed. Tested on 95 individuals from four populations coming from three countries of the Congo Basin, the microsatellites displayed two to 20 alleles (mean 7.5; expected heterozygosity 0.003 to 0.937, mean 0.666). The transferability of microsatellites was effective for four other Dacryodes species (D. buettneri, D. igaganga, D. osika, D. pubescens). This set of newly developed microsatellite markers will be useful for assessing the genetic diversity and differentiation as well as gene flow patterns of D. edulis in tropical forests from Central Africa.