African Ebony Research Articles

Wild Poinsettia, African Ebony and Ashanti Pepper: Potential Biofungicides Against Phytophthora colocasiae Raciborski

Plant extracts could be used as substitutes to synthetic pesticides in the management of fungi and other plant pathogens. The biofungicidal potential of aqueous extracts of wild poinsettia (Euphorbia heterophylla L., a weed) and African ebony (Diospyros crassiflora Hiern, a tree) leaves, and Ashanti pepper (Piper guineense Schumach., a spice) seeds was assessed against Phythophthora colocasiae in vitro. The plants were screened at the rates of 0 (control), 45 and 90%. The synthetic fungicide, mancozeb was included. Results indicated that all the plant extracts were fungitoxic and there was a variation in their potency. Also, the level of inhibition was higher at 90% concentration than at 45%. At 24-120 hours after exposure (HAE), a concentration of 90% Ashanti pepper consistently gave complete inhibition of the fungus similar to mancozeb. Complete inhibition of the fungus was also recorded for 45% Ashanti pepper at 24–48 HAE. At 45% concentration, the inhibitory levels of the extracts were Ashanti pepper: 89.6–100.0%, African ebony: 29.6–33.1 and wild poinsettia: <20.0%. At a concentration of 90%, the levels were Ashanti pepper: 100%, African ebony: 36.7–39.1% and wild poinsettia: 17.1–26.9%. The plant extracts showed promising activity against P. colocasiae and should be exploited for incorporation in management programmes for the fungus.

Assessment of the Effect of West African Ebony (Diospyros mespiliformis) Seed Extracts on Selected Bacteria of Upper River Benue Surface Water

This study was conducted to investigate the effects of D. mespiliformis; crude seed, mucilage and seed extracts on some surface water quality parameters and total bacteria count. The experiment was design as a factorial experiment in Complete Randomized Design (CRD). Sample water was collected from Upper River Benue in Jimeta Bridge. D. mespiliformis purchased at Jimeta Market, Yola Adamawa State. The water sample was collected in Jerry cans (50 litters) transported to wet laboratory, Department of Fisheries, School Agriculture, Modibbo Adama University of Technology Yola where the following physico-chemical parameters were analyzed Electrical Conductivity, Total Dissolve Solid, Ionic Concentration, Temperature, Biological Oxygen Demand and Turbidity. However, Total Bacterial Count was analyzed from microbiology laboratory of same University. Data obtained were analyzed using Analysis of Variance (ANOVA). Result obtained shows the effect of D. mespiliformis treated surface water on the Physicochemical Parameters and effect of D. mespiliformis Crude Seed, Mucilage and Seed Extracts on Total Bacteria Count. The following bacteria Escherichia coli, Bacillus subtilis and Staphylococcus aureus were used during the studies with E. coli has highest total bacteria count of 233 and 22 recorded lowest in seed extract, B. subtilis recorded it highest of 164 and 42 reveal as lowest in the seed mucilage while S. aureus has highest of 100 with it lowest of 32 recorded in mucilage. Further study on the efficacy of D. mespiliformis crude seed, mucilage and seed extracts on contaminant water treatment should be done.

Effect of Seed Processing by Flying Foxes and the Patas Monkey on the Germination Success of the African Ebony (Diospyros mespiliformis)

Abstract Animals deliver an important ecosystem service by dispersing plant seeds. Seed dispersers have different effects on the germination success of seeds. This study aimed at examining the effect of seed processing by the patas monkey (Erythrocebus patas) and two flying foxes (Micropteropus pusillus and Epomophorus gambianus) on the germination success of African ebony (Diospyros mespiliformis). Flying foxes and patas monkeys were kept in cages and fed ad libitum with African ebony fruits. Seeds processed were collected, measured, and germinated. Seeds processed by monkeys and flying foxes were compared to control seeds which were removed by hand from fruits. Our results showed that the patas monkey and flying foxes preferably processed smaller seeds. Flying foxes improved the germination success from 6.67 to 72.5%. They also reduced the mean germination time up to 5 days. The patas monkey also improved the germination success from 6.67 to 52.5% and reduced the mean germination time up to 4 days. The effect of flying foxes and the patas monkey on the seed germination and its implication for the African ebony plantation dynamic should be explained to communities for their conservation.

Fertility Enhancing Effect of Diopyros mespiliformis (African Ebony) Stem Bark on Testes of Wistar Albino Rats: A hormonal study

Diospyros mespiliformis (African ebony) is a plant that is highly recognized all over African and Asian countries, for its medicinal and curative properties. This study investigates the effects of Diospyros mespiliformis aqueous stem bark extract on the testis, epididymal weight and hormonal assay in Wistar albino rats at different doses. Thirty Adult Wistar rats were assigned into five groups of six rats each. With group I serving as control, while group (II, III, IV and V) were treated with 25mg/kg, 50mg/kg 100mg/kg and 100mg/kg (post treatment group) of the extract within the experimental period of twenty eight days. Twenty four hours after the last oral administration, the rats in groups (I- IV) were euthanized for tissue harvesting. The rats in group V were allowed to remain for fourteen days post-treatment and they were euthanized on day fifteen. Testes, epididymis tissues were harvested and weighed, blood samples were collected for hormonal analysis. Investigations revealed an increased in testosterone, follicle stimulating hormone (FSH), luteinizing hormone (LH) serum level in groups (II, III and IV) when compared to groups (I and V). The testis and epididymis weight increased in groups (III and IV) when compared to the groups (I, II and V). The results of the study revealed that aqueous stem bark extract of Diospyros mespiliformis have fertility enhancing potentials on the testis, epididymis and hormonal serum level in Wistar albino rats.
 Keywords: Diospyros mespiliformis, Epididymis, Fertility enhancers, Hormone, Weight

PICT: A low‐cost, modular, open‐source camera trap system to study plant–insect interactions

Abstract Commercial camera traps (CTs) commonly used in wildlife studies have several technical limitations that restrict their scope of application. They are not easily customizable, unit prices sharply increase with image quality and importantly, they are not designed to record the activity of ectotherms such as insects. Those developed for the study of plant–insect interactions are yet to be widely adopted as they rely on expensive and heavy equipment. We developed PICT (plant–insect interactions camera trap), an inexpensive (<100 USD) do‐it‐yourself CT system based on a Raspberry Pi Zero computer designed to continuously film animal activity. The system is particularly well suited for the study of pollination, insect behaviour and predator–prey interactions. The focus distance can be manually adjusted to under 5 cm. In low light conditions, a near‐infrared light automatically illuminates the subject. Frame rate, resolution and video compression levels can be set by the user. The system can be remotely controlled using either a smartphone, tablet or laptop via the onboard Wi‐Fi. PICT can record up to 72‐hr day and night videos at >720p resolution with a 110‐Wh power bank (30,000 mAh). Its ultra‐portable (<1 kg) waterproof design and modular architecture is practical in diverse field settings. We provide an illustrated technical guide detailing the steps involved in building and operating a PICT and for video post‐processing. We successfully field‐tested PICT in a Central African rainforest in two contrasting research settings: an insect pollinator survey in the canopy of the African ebony Diospyros crassiflora and the observation of rare pollination events of an epiphytic orchid Cyrtorchis letouzeyi. PICT overcomes many of the limitations commonly associated with CT systems designed to monitor ectotherms. Increased portability and image quality at lower costs allow for large‐scale deployment and the acquisition of novel insights into the reproductive biology of plants and their interactions with difficult to observe animals. ​

Germination of West African Ebony (Diospyros mespiliformis Hochst) Seeds: Effects of Dehydration and Different Pre-sowing Treatments

Diospyros mespiliformis is a highly valued and threatened tree species within the Sahelo-Sudanian zone of Africa, but its seed germination requirements under cultivation are not well researched. In a first experiment which aimed at determining germination response of seeds to dehydration, fresh seeds were dried at room temperature for 26 days during which their moisture content, their germinability, and their viability were monitored at two-day intervals. In the second experiment, 14 pre-germination treatments were tested for their effect on the germination of dried seeds. Results showed that fresh seeds had 52.7% moisture and achieved 97.7% germination. As seeds were dried, percentage germination gradually decreased with decreasing moisture content and reached 0% when moisture content had dropped to 18%. Meanwhile, seed viability remained at 100% over drying duration. Seeds that were not germinated after air dry also recorded 100% viability. The most effective treatment for inducing germination of dried seeds was scarification using 98% sulfuric acid for 30 min which resulted in 96.6% germination. This study reports for the first time in D. mespiliformis seeds a desiccation-induced dormancy which can be efficiently alleviated by acid scarification. This study provides useful information that will contribute to efficient management of D. mespiliformis seed resources for propagation.

Effect of Methanolic Extract of African Ebony (Diospyros mespiliformis) Stem Bark on Liver and Kidney Function Biomarkers in Alloxan Induced Diabetic Albino Rats

The effect of methanolic extract of African Ebony (Diospyros mespiliformis) on glucose level, liver and kidney function biomarkers in alloxan induced diabetic rat was investigated. The rats were grouped into four of ten (10) rats each. The rats in Group B, C and D were induced with 0.4mL of alloxan. Group C was treated with 0.3 mL of methanol stem back of Diospyros mespiliformis, Group D was treated with 1.3 mL of metformin; Group A non-diabetic and Group B diabetic untreated. There was a significance increase (P<0.05) in serum glucose level (23.95±1.04mmol/L) of diabetic untreated rat when compared with the normal rat (5.59±0.22mmol/L) Group A. There was also a significant difference P<0.05 in glucose level of the Groups treated with extract (15.90±0.29mmol/L) and Group treated with metformin (17.25±0.28mmol/L) when compared with diabetic untreated rat (23.95±1.04mmol/L). The effect of extract on Liver marker enzymes AST shows a significant (P<0.05) decrease in the Group treated with extract (11.00±0.40U/L) and metformin (11.04±1.08U/L) when compared with untreated (12.88±0.53g/L). ALT showed significant (P<0.05) decrease in the Groups treated with extract (11.05±1.07U/L) and metformin (11.02±1.11U/L) when compared with untreated Group (14.58±0.76g/L). There was a significance P<0.05 increase of Total protein in untreated rats (66.00±2.26g/L) when compared with extract (11.25±1.15g/L) and treated with metformin (11.75±1.11g/L). There was a significance P<0.05 decrease in ALB in diabetic untreated (41.25±0.25g/L) when compared with that treated with extract (57.25±4.37g/L) and metformin (60.20±1.88g/L) and untreated rats. The values of renal function, Urea (6.74±1.76) mMol/l for Group A, (6.50±1.56) mMol/l for Group B, (8.87±1.10)mMol/l for Group C and (8.44±1.21) mMol/l for Group D. Creatinine values (0.44±0.01) mMol/l for Group A, (4.02±0.36) mMol/l for Group B, (3.16±0.10) mMol/l for Group C and (0.46±0.10) mMol/l. The stem bark extracts possesses hypoglycemic effect and also has a positive effect on liver and kidney function biomarker.

Antibacterial potency of aqueous and methanolic extracts of Diospyros mesiliformis leaf and stem bark

Diospyros mespiliformis“Jackal berry” (also known as African ebony and by its Afrikaan name Jackal bessie). In hausa its called kanya, igi dudu (black wood) in Yoruba and Onye-oji (Black fellow) in igbo. It is widely used locally in treating various ailments such as fever, whooping cough, wounds, malaria, pheumonia, syphilis, leprosy and host of other ailment without proper scientific validation. This investigation is aimed at validating the scientific use of Diospyros mespiliformis leaf and stem bark using two solvents, methanol and aqueous. Phytochemical screening of the crude extracts revealed the presence of bioactive compounds such as saponins, tannins, alkaloids flavonoids, steroids, terpenoids and glycoside. The extracts were tested against Escherichia coli, Salmonella typhi and Staphylococcus aureus respectively. The antibacterial activity of the stem bark extracts revealed higher activity against E. coli, S.typhi and S. aureus than the leaf extracts. The mean range of zones of inhibition of stem bark at 100mg/ml and 12.5mg/ml varies between 19.29± 3.82 and 5.71± 2.05 while that of leaf extract ranges from 17.71± 2.06 and 5.43±1.13 at 100mg/ml and 12.5 respectively.
 Key words: Antibacterial, Phytochemicals, Diospyros mespiliformis, Minimum Inhibitory Concentration.

Micropropagation and Effect of Phloroglucinol on Rooting of Diospyros crassiflora Hiern

The jet-black to streaked ebony wood produced by the African ebony (Diospyros crassiflora Hiern, Ebenaceae) is exploited in Central and West Africa. A conservation effort is currently underway in Cameroon to propagate the tree through seedlings and cuttings. However, the intermittent availability of its seeds and the long time required for rooting formation of cuttings are limiting its propagation. This study aims to develop a successful protocol for ebony micropropagation. In vitro culture of nodal segments from seedlings was performed in half-strength Murashige and Skoog (MS) medium supplemented with either zeatin (0.0, 2.3, 4.6, 9.1, 13.7, 18.2, 22.8, and 27.4 µm) or 6-benzylaminopurine (BAP) (0.0, 2.2, 4.4, 8.8, 13.3, 17.8, 22.2, and 26.6 µm). After 12 weeks, all media allowed shoot budbreak. Shoots displaying the greatest budbreak were observed with 22.8 µm zeatin and 22.2 µm BAP. The shoots were then transferred to a medium supplemented with indole-3-butyric acid (IBA) and phloroglucinol (PG) at different concentrations for root induction. Root induction was observed on the shoots initially induced in the medium with BAP, but not in those grown in the medium with zeatin. In half-strength MS supplemented with 396.5 µm PG plus 14.2 µm IBA, the formation of a single tap root was observed on 79% of shoots, with an average root length of 2.8 ± 0.18 cm. Rooted plants were successfully acclimatized to the greenhouse, with a 50% survival rate. This is the first report on Diospyros crassiflora micropropagation, which paves the way for rapid ebony multiplication to respond to needed conservation efforts.

Acute and sub-chronic toxicity evaluation of the crude methanolic extract of Diospyros mespiliformis hochst ex a. Dc (ebenaceae) and its fractions

Diospyros mespiliformis, commonly called Jackal berry or African ebony, belongs to the plant family, Ebenaceae. The roots, barks and leaves have been used traditionally to treat wide varieties of conditions, however, there is limited information and literature reports concerning the toxicity and safety of this plant. The present study was conducted to evaluate the acute and sub-chronic toxicity of the crude methanolic extract of Diospyros mespiliformis and its fraction in Wistar rats. Diospyros mespiliformis was extracted by methanol 96 %. The crude methanolic extract was then fractionated into low, average and high polar compounds using hexane, ethyl acetate and butanol respectively. For the acute toxicity study, the revised limit Dose Test of “Up and Down” procedure according to the OECD guideline was used to determine the median lethal dose (LD50) of the crude methanolic leaf and bark extracts using a single fixed dose (5 g/kg) of the extracts administered by oral-gavage sequentially to 5 female Wistar rats. The rats were observed for instant death and toxicity signs for 24 h and then daily for 14 days. In the sub-chronic toxicity study, the bark and leaf ethyl acetate fractions (extract) was administered orally at doses of 250, 500 and 750 mg/kg bw /day respectively for 28 days to healthy Wistar rats. At the end of the experimental period, body weight, certain haematological, serum biochemical and histopathological parameters were evaluated. Results showed that acute oral administration of crude methanolic extract of Diospyros mespiliformis (5 g/kg bw) produced neither mortality nor visible changes in behavior or any other physiological activities and indicated that the LD50 of crude methanolic leaf and bark extract was greater than 5 g/kg bw in Wistar Rats. In the 28-days repeated dose oral toxicity study, no significant toxic effects was detected in any of the parameters evaluated. In conclusion, the crude methanolic extract was found safe in the acute toxicity study and the ethyl acetate fraction of Diospyros mespiliformis in the sub chronic study in rats could be safe for therapeutic purposes over a period not exceeding 28 days.

Effect of wood on the sound of oboe as simulated by the chanter of a 16-inch French bagpipe

Many objective and subjective experiments on brass instruments, organs, flutes and clarinets have shown that the influence of material was weak. Yet, the influence of wood on the sound of oboes is still to be determined. In this study, short musical recordings of ten French 16″ bagpipes made of 5 different woods (African Ebony, Santos Rosewood, Boxwood, African Blackwood and Service Tree) were presented to subjects (specialist and naïve), who had to give their feedback on several criteria (global quality, warmth, aggressiveness, brightness, volume and attack precision). The choice of a bagpipe rather than a simple oboe enables to minimize the influence of the musician, as he is not directly in contact with the reed. An influence of the reed material was found, but no influence of the wood. In a second experiment, a discrimination task allowed to confirm that the differences between chanters were not principally due to the wood. Several physical parameters calculated from recorded signals could also not reveal any large differences between woods.

Germination Effects of Purposive Bruchid Screening of African Ebony (Dalbergia Melanoxylon) Seeds In the Arid and Semi-Arid Region of South Eastern Kenya

The African ebony (Dalbergia melanoxylon) is a tree that is crucial in making of high value wooden traditional artifacts, however its slow growth in the arid and semi-arid lands (ASALs), poor germination and low seedling growth rate, seed pest predation coupled with overharvesting pause a great threat for the future availability of the species. Unscreened natural methods of seed germination might not sustainably solve the problem of low germination. Overharvesting for wood carving, and low natural regenerative ability of the species and lack of the local and national conservation efforts present a serious threat its availability to the future availability of Dalbergia melanoxylon. Availability of viable seed plays a crucial role the establishment of African ebony. There is need for immediate methods for multiple seedling production for propagation of D. melanoxylon. Our studies showed 2% germination without screening but increased to 40% after screening (p< 0.001). Careful moisture monitoring of the seedling seemed to increase the growth rate in the ASAL region. Therefore, selected propagation methods of this species can rescue it from the current extinction trend which is caused by its low regenerative ability when natural methods are used and over exploitation. There is need to support on farm cultivation of the tree to sustain the carving industry.

Methodology Optimization of DNA extraction from fresh leaf tissues of Melanoxylon brauna (Fabaceae)

Melanoxylon brauna (Fabaceae - Caesalpinioideae) is an endemic and valuable hardwood tree species in the Brazilian Atlantic rainforest; it is comparable to African ebony wood. We tested three protocols of DNA extraction based on the citrimonium bromide (CTAB) method and evaluated the quantity, purity and integrity of the DNA. We also determined whether these procedures interfere with PCR amplification in order to develop a protocol for M. brauna. We found that the quality and integrity of DNA were improved with the use of proteinase K in the extraction buffer and by modifications in the centrifugation speed. The lowest concentration of DNA was obtained with Doyle and Doyle's protocol (5.42 ng/μL). Ferreira and Grattapaglia's protocol modified for M. brauna provided the most DNA (36.89 ng/μL) and the highest quality DNA (purity ratio of 1.80 nm). The original Ferreira and Grattapaglia protocol provided 13.42 ng/μL DNA; however, the purity ratio (1.44 nm) indicates protein contamination. PCR results showed that Ferreira and Grattapaglia's protocol modified for M. brauna gave satisfactory quantity and purity of DNA for molecular studies.

ChemInform Abstract: Synthesis of the Reported Structure of Crassiflorone, a Naturally Occurring Quinone Isolated from the African Ebony Diospyros crassiflora, and Regioisomeric Pentacyclic Furocoumarin Naphthoquinones.

AbstractThe synthesis of the proposed structure of crassiflorone (Ia) as well as that of three regioisomers (Ib), (II) is presented.

Synthesis of the reported structure of crassiflorone, a naturally occurring quinone isolated from the African ebony Diospyros crassiflora, and regioisomeric pentacyclic furocoumarin naphthoquinones

A synthesis of the structure reported for the natural product crassiflorone, a furocoumarin naphthoquinone, is described. The key steps are a Diels-Alder reaction to form 2-bromo-8-hydroxy-6-methylnaphthoquinone, followed by O-protection and copper(II) mediated coupling to 4-hydroxy-5-methylcoumarin to establish the pentacyclic framework whose structure was unambiguously confirmed by X-ray crystallography. Since the spectroscopic data of the synthetic material did not match those reported for the natural product, three further regioisomeric furocoumarin naphthoquinones were prepared by copper(II) mediated coupling of 4-hydroxy-5- or 8-methyl coumarins with 5-benzyloxy-2-bromo-7-methyl- or 8-benzyloxy-2-bromo-6-methyl-1,4-naphthoquinone. Again the spectroscopic data did not match those of the natural material and therefore the true structure of crassiflorone remains unknown.

Synthesis of the Reported Structure of Crassiflorone, a Pentacyclic Naphthoquinone Isolated from the African Ebony Diospyros crassiflora

A short synthesis of the furocoumarin naphthoquinone structure reported for the natural product crassiflorone is descnbed, in which the key steps are a Diels-Alder reaction to form 2-bromo-8-hydroxy-6-methylnaphthoquinone, followed by O-protection and copper(II)-mediated coupling to 4-hydroxy-5-methylcoumarin to establish the pentacyclic framework.

The influence of tourism on the woodcarving trade around Cape Town and implications for forest resources in southern Africa

Woodcarving is an important informal sector industry that is heavily dependent on tourism and yet sustains the livelihoods of many migrant communities in South Africa. In the Cape Town area, the trade appears to be dominated by sellers from neighbouring countries, including Zimbabwe, Malawi and the Democratic Republic of Congo. The most traded wood species are Dalbergia melanoxylon (African ebony), Brachylaena huillensis (silver oak or muhuhu) and Afzelia quanzensis (pod mahogany). This study found that the average gross income from the trade was R6450 and R2692 per month in the tourism peak and off seasons, respectively. However, while the woodcarving industry provides an important source of informal employment, it has contributed to the scarcity of highly prized hardwood species, especially in impoverished, underdeveloped areas.

Sound quality of the 16'' french bagpipe: wood influence

The most played among the bagpipes from the centre of France is the 16‐inch musette, called in this way because of the length of the melodic pipe (oboe). Though these instruments are less known than the biniou from Brittany or the Great Highland Bagpipe, the number of players and makers is, nowadays, in increase because of their easy play and quasi‐chromatic scale. Whereas the Breton and Scottish bagpipes are always made of very hard woods, some 16'' musettes are fabricated with softer woods. This difference is certainly related to the flexibility of the 16'' oboe double‐reed. At first, we recorded some short musical sequences played on 16'' musettes made of 5 different woods (African Ebony, Santos Rosewood, Boxwood, African Blackwood and Service Tree), then some listeners (specialist and naïve) were asked to give their feedback about the quality of the recorded sounds. In a second set of experiments, we recorded some single notes played with these various bagpipes and analyzed the acoustic features of the recorded signals. At last, the perceptual results were compared with the physical parameters obtained in the second experiment.

Current sculptural art of the Makonde, Mozambique, as a world-view.

Este artigo discute a noção de “arte tradicional” e de “autenticidade”, correntes no discurso sobre a arte africana, a partir do estudo da arte escultórica dos WaMakonde do norte de Moçambique. Diferenciando-se da escultura dominante na África Austral, os Wa-Makonde, atualmente, esculpem segundo dois tipos básicos, chamados ujamaa e shetani, e utilizam o ébano como matéria-prima. Procura-se mostrar que esta arte, criada nos anos 50-60, é uma re-elaboração plástica de experiências coletivas e que ela pode ser considerada como uma visão de mundo na qual estão atualizados valores ancestrais.