Alstonia Boonei Research Articles

Antimalarial Therapies and Infertility:A Comprehensive Review

Apart from other factors associated with infertility, scientific literatures had shown that synthetic and herbal antimalarial agents are also associated with reproductive disorders. However, there is paucity of review update on the reproductive toxicity posed by these antimalarial agents. With the aid of the internet data base, relevant literatures on this subjects matter were reviewed in this evaluation. Among the synthetic and herbal antimalarials investigated, Quinine, Piperaquine phosphate, Chloroquine, Proguanil, halofantrine hydrochloride, Pyrimethamine, Arthemeter- Lumefantrine, ACTs (artesunate), Artemether, Azadirachta indica (Neem), Phyllanthus amarus, Alstonia boonei , except (sulfadoxine/pyrimethamine), were associated with diverse reproductive toxicities. Proposed mechanisms of such toxicities include; reduction in follicle stimulating hormone, leuteinizing hormone and testosterone levels, impairments in sperm parameters, antifolate (Pyrimethamine) activity, anti-androgenic activity, distortion of the blood-testis barrier formed by the sertoli cells and increase reactive oxygen species (ROS). On this basis, antimalarial therapies (synthetic and medicinal plants) should be used with caution, especially during pregnancy. Also, reproductive toxicities of new antimalarial drugs being launched into the marked should be screened to ascertain their safety.

Plants used in Bandjoun village (La'Djo) to cure infectious diseases: An ethnopharmacology survey and in-vitro Time-Kill Assessment of some of them against Escherichia coli

An ethnopharmacology survey concerning the medicinal plants used in Bandjoun village (La'Djo) to cure infectious diseases was carried out in three districts of this village. The survey led to the identification of 79 medicinal plants species listed in 41 families. These plants were cited to be use to treat about 25 infectious diseases among which malaria, diarrhea and intestinal-worms were the most cited. Chromolaena odorata, Voacanga africana, Moringa oleifera, Mammea africana, Euphorbia hirta, Psidium guajava, Allium cepa, Enantia chlorantha, Alstonia boonei and Picralima nitida, were the ten most cited plants. Extractions of parts of these last plants were performed in hydro-ethanol (3:7) solvent and then tested in-vitro against an Escherichia coli isolate. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were assessed by microdilution assay and the time-kill assessment was carried out by measure of log reduction in viable cell count, on a period of 48 hours. MIC and MBC determined were ranged between 1.00 and 32.0 mg/mL. Eighty percent (80%) of plant extracts tested have been bactericidal (MBC/MIC = 1 or 2) after 24 hours of incubation. A significant dose-dependent decreasing (P<0.05) in test organisms population was observed in the time with log reduction in viable cell count was ranged between 0.13 log10cfu/mL and 100% of inhibition. This antimicrobial activity has been attributed to metabolites groups in plant extracts namely, Phenols, flavonoids, tannins, coumarins, terpenoids, anthraquinones, cardiac glycosides, anthocyanides and alkaloids. These results obtained against Escherichia coli give a scientific validation to the traditional medical knowledge of Bandjoun-village populations and confirm some of the plants identified like a source of potentially active compounds against infectious diseases.

Formulation and Evaluation of Alstonia boonei Stem Bark Powder Tablets.

The aim of this work was to formulate Alstonia boonei dried stem bark powder into tablets by wet granulation method using acacia, gelatine and sodium carboxymethyl cellulose as binders at concentrations of 1, 2, 4 and 8% w/w. The phytochemistry of the stem bark of Alstonia boonei was evaluated. The micromeritic properties of the granules prepared were studied. The tablets were evaluated using the necessary official and unofficial tests. The results of the phytochemical analysis showed that alkaloids, tannins, steroids, saponins, glycosides, flavonoids and terpenoids were present while anthroquinones and acidcompounds were absent. Micromeritic studies showed that Alstonia boonei granules had good flowability. The formulated tablets complied with British Pharmacopoeial specification for weight uniformity, hardness (≥5 kgf) and tablet friability (<1%). For disintegration test, tablets formulated with gelatine and acacia at concentrations of 1, 2 and 4% w/w complied with Pharmacopoeial specification. However, tablets formulated with SCMC (1-8% w/w) and 8% w/w of acacia and gelatine failed the disintegration tests (Disintegration time more than 15 min).

Evaluation of herbal antimalarial MAMA decoction-amodiaquine combination in murine malaria model

Context: Co-administration of amodiaquine with MAMA decoction (MD), an herbal antimalarial drug comprising the leaves of Mangifera indica L. (Anacardiaceae), Alstonia boonei De Wild (Apocynaceae), Morinda lucida Benth (Rubiaceae) and Azadirachta indica A. Juss (Meliaceae) was investigated. The practice of concurrent administration of herbal medicines with orthodox drugs is currently on the increase globally.Objective: The study was designed to investigate the possible enhancement of the antimalarial potency as well as possible herb–drug interaction resulting from concurrent administration of MAMA decoction with amodiaquine (AQ).Materials and methods: Combinations of MD with AQ were investigated in chloroquine (CQ)-sensitive Plasmodium berghei NK 65 in varying oral doses (mg/kg) at: sub-therapeutic [MD30 + AQ1.25], therapeutic [MD120 + AQ10] and median effective [MD40 + AQ3.8], using chemosuppressive and curative antimalarial test models. Secondly, P. berghei ANKA (CQ-resistant)-infected mice were orally treated with MD 120, 240, [MD120 + AQ10] and [MD240 + AQ10] mg/kg, using both models. The survival times of mice were monitored for 28 d.Results: ED50 values of MD and AQ were 48.8 and 4.1 mg/kg, respectively. A total parasite clearance of CQ-sensitive P. berghei NK65 was obtained with the therapeutic combination dose in the curative test giving an enhanced survival time. In CQ-resistant P. berghei ANKA-infected mice, [MD120 + AQ10] and [MD240 + AQ10] mg/kg gave comparable activities with AQ (10 mg/kg) in both models.Conclusion: The therapeutic combination dose gave total parasite clearance of CQ-sensitive P. berghei NK65, whereas none of the doses tested showed notable activity against CQ-resistant P. berghei ANKA.

English

Alstonia boonei De Wild ethanol extracts of the stem bark (ABSB) and root bark (ABRB) were evaluated for possible anthelmintic activity. Three different concentrations of each extract (50, 100 and 150 mg/ml) were evaluated for in vitro anthelmintic activity by determining the effects of the extracts on the paralysis and death times of Pheretima posthuma. Mebendazole (MBZ) 15 mg/mg was used as reference anthelmintic. ABSB and ABRB demonstrated a concentration dependent anthelmintic activity with a reduction in paralytic and death times upon increase in the concentration of the extracts. ABSB revealed better anthelmintic activity than ABRB at all concentrations tested. ABSB also revealed a significant paralytic time (p<0.01) at 150 mg/ml with reference to MBZ. Phytochemical screening revealed the presence of alkaloids, tannins, flavonoids saponins and glycosides in ABSB and ABRB. Key words: Alstonia boonei, anthelmintic, Pheretima posthuma, death time, paralytic time.

Antidiabetic and Plasma Endogenous Antioxidant Activity of &lt;i&gt;alstonia boonei&lt;/i&gt; in Alloxan-Induced Male Diabetic Rabbits

Alstonia boonei is a well-known plant of medicinal value but its effect on endogenous plasma antioxidant in diabetes remains unknown. Thus, need to investigate the effects of the methanolic extract of the plant on plasma bilirubin and uric acid level in alloxan induced diabetes rabbits. Twenty five rabbits divided into five groups of four rabbits each were used. There was a significant change in the levels of total bilirubin and uric acid in the plasma of treated groups as compared with both non diabetes and untreated diabetes group, while conjugated bilirubin level was relatively unchanged in the treated group. This work clearly indicates that methanolic extract of Alstonia boonei stem bark is effective in the management of diabetes as well as restoration of lost endogenous plasma antioxidants experienced in diabetes mellitus.

Antimalarial Properties of Morinda lucida and Alstonia boonei on Sulphadoxine-Pyrimethamine and Curcuma longa on Quinine in Mice

The antimalarial activities of Morinda lucida (MLE), Alstonia boonei (ABE), Curcuma longa (CLE) at 12.5–400 mg kg−1, sulphadoxine-pyrimethamine (S-P), and quinine at 0.2–1.7 and 0.625–10 mg kg−1, respectively, were investigated in Plasmodium berghei–infected mice using the 4-d malaria test. Assessment of MLE plus S-P, ABE plus S-P, and CLE plus quinine was similarly done. Dose-dependent activities were noted with MLE, ABE, and CLE with chemosuppression values of 39.8–90.5, 0.2–74.8, and 34.6–78.4%, respectively. The combinations gave 1.8- to 2.5-fold greater chemosuppression than the individual drug/extracts. The efficacies of S-P and quinine were enhanced when combined with the extracts.

In vitro antiplasmodial activity and phytochemical screening of Alstonia boonei De wild used in treating malaria-associated symptoms

This study investigated the In vitro antiplasmodial activity and phytochemical constituents of the leaves from Alstonia boonei used in the local treatment of malaria. The crude ethanol extract from the medicinal plant (AB-01) was fractionated into ethyl acetate (AB-01-01), chloroform (AB-01-02) and n-hexane (AB-01-03) fractions. In vitro antiplasmodial assays and phytochemical screening of ethyl acetate, chloroform and n-hexane fractions from the plant were further carried out. Alkaloids, saponins tannins, flavonoids, steroids and glycosides were detected in the extracts of the plant. Plants leaves extracts and fractions were found to be active against Plasmodium falciparum with percentage elimination range of 40.90 to 81.81%. The analysis of the results of the extract and that of the standard (positive control) using Mann-Whitny U test indicate that there is no significant difference between them. Spearman rank correlation analysis of the plant samples with the positive control samples showed that there is correlation and the degree of relationship between the antiplasmodial activities of the plant samples and positive control samples is positively perfect (?s = 1).

The use of ethnobotanicals in the management of inflammation in Nigeria: a review

Inflammation, one of the leading health issues in recent times call for concern. Many plants used in the management and treatment of inflammation in various parts of Nigeria have not been properly harnessed hence this review. The result of this review revealed that plants commonly used for the treatment of inflammation include: Zingiber officinale, Alstonia boonei, Plumbago zeylanica, Ocimum basilicum, Parquetina nigrescens, Peperomia pellucida, Abrus precatorius, Tetrapleura tetraptera, Alchornea cordifolia, Terminalia ivorensis, Aspilia africana, Ageratum conyzoides and Hymenocardia acida. Altogether 74 plant species are ethnobotanicals used in the management and treatment of inflammation. The plants were enumerated with their family names, common and local names, possible chemical constituents, part(s) used, route of administration and subsequent references where available.DOI: http://dx.doi.org/10.3126/ije.v4i2.12620 International Journal of Environment Vol.4(2) 2015: 1-18

Subchronic toxicity of aqueous extract of Alstonia boonei de wild. (apocynaceae) stem bark in normal rats

Methodology: Wistar rats were randomly assigned into eight groups of five animals each: four male groups and four female groups. Each sex group had a control group receiving distilled water and three test groups receiving 200, 500 and 1000mg/kg respectively. Animal’s body weights were recorded on the first day and once a week for the four experiment weeks. The hematological analysis included total WBC count, total RBC count, Hb, %HCT, MCV, MCH and MCHC. Biochemical/serum profile studies include TG, TC, ALT, AST, urea and TP. Tissue specimens of the liver, kidney and lung were subjected to histological examination using standard hematoxylin-eosin staining.Results: In male rats, aqueous extract showed significant decreases in relative weight of liver with extreme significance P&lt;0.001 at a dose of 200mg/kg (vs. control group), P&lt;0.001 of lung at all the doses, P&lt;0.05 (200 and 500mg/kg) and P&lt;0.01 (1000mg/kg) in heart weight. In relative kidney weight, only the dose of 1000mg/kg showed a significant increase vs. normal control male rats. Unlike male rats, only relative kidney weight in female rats was significantly different from the control group in a dose-dependent manner. The aqueous extract treated male groups showed significant increases P&lt;0.001 (1000mg/kg) of total WBC count and MCHC, significant decreases of %HTC (dose response manner), P&lt;0.05 total RBC count (at doses of 500 and 1000mg/kg) and Hb P&lt;0.01 (500mg/kg) vs. normal male rats. In female rats, the haematological study showed significant increase P&lt;0.01 of total WBC count (at the doses of 500 and 1000mg/kg), significant decreases P&lt;0.05 and P&lt;0.01 of total RBC respectively at the doses of 200 and 1000mg/kg, significant decrease of Hb with extreme significance P&lt;0.001 at the dose 1000mg/kg, %HTC also decrease dose response manner vs. control female rats. Biochemical study showed in male rats significant decreases in level of TG P&lt;0.001 (at the doses of 200 and 500mg/kg) and urea, although it showed any dose-dependent effect vs. control male rats. AST also decreases (P&lt;0.05) in male rats at the dose of 200mg/kg but significantly increase P&lt;0.001 at the dose of 500mg/kg. In the female rats, biochemical study revealed significant increases in level of TG P&lt;0.001 and urea P&lt;0.01 at the dose of 200mg/kg and significant decreases in level of TG P&lt;0.01, AST P&lt;0.05 and urea P&lt;0.05 at the dose of 500mg/kg (vs. control female rats). Microscopically, there were mild hepatic and renal tissue injuries supporting the hematological analysis.Conclusion: The results indicated that aqueous extract of Alstonia boonei De Wild is toxic in high doses.

INDIGENOUS USES AND PHYTOCHEMICAL CONTENTS OF PLANTS USED IN THE TREATMENT OF MENSTRUAL DISORDERS AND AFTER- CHILD BIRTH PROBLEMS IN ABEOKUTA SOUTH LOCAL GOVERNMENT AREA OF OGUN STATE, NIGERIA

A survey of plants used for the treatment of menstrual disorders and after-child birth problems was conducted in Abeokuta South Local Government. Hundred (100) questionnaires were administered using multi stage sampling method on traditional herbal practitioners. Ethnobotanical information such as, plants and plant parts used, methods of extraction used and mode of administration of the herbal preparations of these plants were requested. Also, phytochemical contents of the most frequently mentioned plants were determined. Data were subjected to Analysis of variance (ANOVA) with probability set at p<0.05 and descriptive statistics. Results revealed that a total of fifty-six (56) plants belonging to 37 families were mentioned. The most frequently mentioned families are Euphorbiaceae, Leguminoceae, Anacardiaceae, Apocynaceae, Araceae and Combretaceae. Sesamum indicum, Dioclea sarmentosa, Clausena anisata, Anogeissus leiocarpus, Alafia barteri, Tetrapleura tetraptera, Daniella oliveri, Lannea egregia and Alstonia boonei were the most frequently mentioned plants used in the treatment of menstrual disorders and after-childbirth problems. Leaves (34%), fruits (7%), flowers (3%), tubers (2%), stem-barks (28%), seeds (11%) , roots and barks (2%) and roots (13%) were the plants reported being used for the remedy of these disorders. Decoction (54%), squeezing (9%), grinding/squeezing (14%), paste (4%), exudation (4%), cooking (4%), soaking/ decoction/infusion (4%), and heating to ashes (4%) were the methods of extracting the bioactive principles of the plants using water (79%) as major solvent. Significant difference (P < 0.05) was observed in the quantities of  tannins recorded in the leaves of Sesamun indicum, Dioclea sarmentosa, Clausena anisata, Anogeissus leiocarpus and Alafia barteri. Similar observations were found in the quantities of saponnins, alkaloids, flavonoids and phenol. Highest values of tannins (0.32mg/g), saponnins (1.07mg/g), alkaloids (5.16mg/g), flavonoids (3.12mg/g) and phenol (0.09 mg/g) were determined in the leaves of  Clausena anisata, Sesanum indicum, Dioclea sarmentosa and Alafia barteri. Across the roots of these plants, similar amount of tannins and saponnins were quantified. This observation varied significantly when compared with alkaloids, flavonoids and phenol quantified in the roots of plants. Highest tannins (1.67mg/g) and saponnins (3.33 mg/g) were recorded in the roots of Dioclea sarmentosa, alkaloids (4.33 mg/g) and flavonoid (6.33 mg/g) in Anogeissus leiocarpus while phenol (1.33 mg/g) was recorded in roots of Sesanum indicum.  Key words: Menstrual Disorders, Childbirth Problems, phytochemical contents, Traditional practitioners, Indigenous plants

Medicinal plants and traditional healing practices in Ehotile people, around the Aby Lagoon (eastern littoral of Côte d'Ivoire).

BackgroundAccess to useful plants is a growing problem in Africa, increased by the loss of natural vegetation and the erosion of traditional knowledge. Ethnobotany contributes to promote these indigenous knowledge. Despite the large diversity of ethnic groups in Côte d’Ivoire, few ethnomedicine researches have targeted these groups. Among the great Akan group, the Ehotile people are one of the smallest and oldest ethnic group around the Aby Lagoon. The goal of this study was to analyze the level of knowledge and use of medicinal plants by the Ehotile people, and moreover, contribute to build a database about useful plants of first Ivorian people.MethodsTwo sets of surveys were conducted in four Ehotile villages: a house-to-house freelist interview and an individual walk-in-the woods interview with some key informants identified by the community. Frequency of citation, Smith’s index, Use value and Informant Consensus Factor were used to estimate the local knowledge of medicinal plants.ResultsMedicinal plants are widely used by Ehotile people. Some were used in addition to modern prescriptions while for some disorders commonly called “African diseases” only plants are used. 123 species employed in the treatment of 57 diseases were listed. Specifically, the most common indications included malaria, sexual asthenia, troubles linked to pregnancy, dysmenorrhoea and haemorrhoids. Analysis of freelists suggested that Ehotile people has a good knowledge of medicinal plants and the most salient included Harungana madagascariensis, Alstonia boonei, Ocimum gratissimum and Xylopia acutiflora. Regarding the consensus among key informants, ICF values were low (<0.5), however category of infectious and parasitic diseases obtained the best agreement (ICF = 0.42). Following the local experts, 4 types of plants availability were distinguished: Abundant plants easy to collect, abundant plants difficult to harvest, scarce plants and endangered plants.ConclusionsDespite the virtual disappearance of natural formations in Ehotile land, medicinal plants are important in the Ehotile health system. Medicinal plants are known and used alone or in addition to medical prescriptions to treat several ailments. However, some of them are becoming rare, and it is feared that this scarcity will result in the inevitable loss of associated knowledge and practices.

Antiplasmodial Properties, Toxicity and Novelty-Induced Behavior of a Formulation from Picralima nitida and Alstonia boonei

Aims: This study aimed at investigating the antiplasmodial activities of the combination of Alstonia boonei De Wild (Apocynaceae) stem-bark and Picralima nitida (Stapf) T.H EJMP, 8(2): 112-120, 2015; Article no.EJMP.2015.096 113 safety of MS. Methodology: Swiss albino mice of both sexes, (18-22 g), were used for the antiplasmodial experiments with the freeze-dried extractive from the decoction of the 1:1 mixture of the two plants against chloroquine-sensitive Plasmodium berghei NK65 strain. For the toxicity and noveltyinduced behavioral (NIB) studies, twenty four rats were divided into four groups (n=6 per group) for three dose (150, 300 and 600 mg/kg) levels of MS and the vehicle (distilled water). The NIB was observed on days 1 and 30 of administration of MS and the vehicle. The animals were sacrificed on day 30 and blood harvested for biochemical assays. Results: The results of the antiplasmodial investigation showed that 12.5 mg/kg extractive of the plant mixture gave antiplasmodial activity equivalent to 82% of the activity of chloroquine (5 mg/kg). The NIB results showed that acute oral administration of MS had no significant effects while the sub-chronic administration caused a significant (P<0.05) increase in rearing but decrease in grooming behaviours, dose-dependently. The biochemical parameters were not affected by the administration of MS at all doses used. Conclusion: The extractive of the plant mixture possessed antiplasmodial activity while the oral sub-chronic administration of MAMA Syrup had central excitatory effects but no significant toxicity

Dichlorvos‑induced oxidative stress in rat brain: Protective effects of the ethanolic extract of Alstonia boonei stem bark

Organophosphorous pesticides, commonly used in agriculture for achieving better‐quality products, are toxic substances that have harmful effects on human health. Recent research on pesticides, especially pesticide mixtures, has shown that they are one of the key environmental health issues. The aim of the present study was to investigate the protective effects of Alstonia boonei ethanolic extract in dichlorvos‐induced neurotoxicity in Wistar rats. Dichlorvos (50 mg/kg body weight) was orally administered in Wistar rats for 14 days followed by the treatment of Alstonia boonei (200 and 400 mg/kg body weight) for 14 days. The activities of lipid peroxidation (LPO), reduced glutathione (GSH) and activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level were measured to evaluate the toxicity of these pesticides in the brain. Histological examinations of the brain were monitored. Under the influence of dichlorvos, there was significant decrease in the activities of SOD, CAT, GPx, GSH, ALT and AST and significant increase in malondialdehyde. Alstonia boonei showed a significant brain‐protective effect by decreasing the level of lipid peroxidation and elevating the activities of antioxidative enzymes and the level of GSH. Furthermore, histological alterations in the brain were observed in dichlorvos‐untreated rats and were ameliorated in dichlorvos‐induced treated rats with Alstonia boonei. The observations presented lead us to conclude the harmful effects of dichlorovos during the exposure and the protective role of Alstonia boonei in minimizing these effects. Key words: Alstonia boonei, brain, dichlorvos, lipid peroxidation, organophosphate, oxidative stress, reactive oxygen species

Sustainable Harvesting of Alstonia boonei De Wild. (Apocynaceae) in the Community Forest of Mbeth II, East Region of Cameroon

This paper aims to analyze the traditional usages and, assess the abundance of stems and the mass of the barks of Alstonia boonei for its use as a medicinal plant in the community forest of Mbeth II, East region of Cameroon. Ethnobotanical surveys were conducted among the community of Mbeth II and in city markets in Bertoua and Yaounde between January and April 2012. The management inventory was conducted in July 2012 to assess the abundance of A. boonei stems in the forest. During the inventory, samples of barks were collected from mature trees and the mass of the stem barks of A. boonei was estimated using an indirect method. A. boonei was cited by 26 informants in the village and markets in the treatment of six ailments. Malaria, typhoid fever and intestinal worms were largely cited. The stem bark is confirmed for its activity against malaria/fever. The density (number of stems/ha) of A. boonei obtained in the Community forest of Mbeth II was 0.89 stems/ha. The density of exploitable stems was therefore 0.744 stems/ha. The average volume of fresh bark for an exploitable tree is 0.0356 m3, while the average fresh mass of the bark of an exploitable tree was 34.4 kg. Considering that for all trees above 30 cm diameter at breast high (considered as a minimum exploitable diameter for the harvesting of barks), only two quarters of the bark are taken from the main stem up to the first branch, the average sustainable mass of Alstonia boonei in Mbeth II is 17.2 kg. Results discussed in this paper can be summarized, in a specific document called “the simple management plan of A. boonei as a medicinal plant in the community forest of Mbeth II”. The glaring development challenge at the back ground of what precedes is the urgent need to achieve the recommendations proposed in such a document.

Beta-Amyrin and alpha-amyrin acetate isolated from the stem bark of Alstonia boonei display profound anti-inflammatory activity

Context: Alstonia boonei De Wild (Apocyanaceae) is used in ethnomedicine for the management of malaria, ulcer, rhematic pain, toothache, and inflammatory disorders.Objective: To investigate the anti-inflammatory potential of β-amyrin and α-amyrin acetate isolated from the stem bark of Alstonia boonei using animal models.Materials and methods: Chromatographic purification of the crude methanol extract led to the isolation and structure elucidation of β-amyrin and α-amyrin acetate. Their anti-inflammatory activities were evaluated in rodents using egg albumen-induced paw edema and xylene-induced ear edema models. The gastric ulcerogenic, in vivo leucocyte migration, and RBC membrane stabilization tests were also investigated.Results: α-Amyrin acetate at 100 mg/kg showed significant (p < 0.05) inhibition of egg albumen-induced paw edema with % inhibition of 40 at the 5th hour. Oral administration up to 100 mg/kg did not produce significant (p > 0.01) irritation of the gastric mucosa while significant (p < 0.01) ulceration was recorded for indomethacin at 40 mg/kg compared with the negative control. At 100 μg/mL, both β-amyrin and α-amyrin acetate inhibited heat-induced hemolysis to as much 47.2 and 61.5%, respectively, while diclofenac sodium (100 μg/mL) evoked only 40.5% inhibition. Both compounds at 100 µg/ear produced significant (p < 0.01) inhibition of ear edema in mice by 39.4 and 55.5%, respectively. Also at 100 mg/kg (p.o.) α-amyrin acetate evoked 60.3% reduction in total leucocyte count and significant (p < 0.05) suppression (47.9%) of neutrophil infiltration.Discussion and conclusion: This study generally provided evidence of profound anti-inflammatory activity of β-amyrin and α-amyrin acetate isolated from the Alstonia boonei stem bark.

Influence of formulation ratio of the plant components on the antimalarial properties of MAMA decoction

Mangifera indica, Alstonia boonei, Morinda lucida and Azadirachta indica (MAMA) decoction, commonly prepared and used in Nigeria from 1:1:1:1 ratio of Mangifera indica L. (Anacardiaceae), Alstonia boonei De Wild (Apocynaceae), Morinda lucida Benth (Rubiaceae), and Azadirachta indica A. Juss (Meliaceae) leaves, plus four new variants of this combination were subjected to three in vivo antimalarial test models using chloroquine-sensitive Plasmodium berghei berghei to determine the most active under each of the test models. Using the original formulation, MAMA (1:1:1:1) which gave ED50 and ED90 of 101.54±2.95 and 227.18±2.95, respectively, as reference for comparison, MAMA-1 (1:2:2:2), with 79.58±1.30 and 170.98±1.30, gave significantly (p<0.05) higher survival at 85 and 340 mg/kg when 80 % of the mice survived for 15.6 and 17.8 days, respectively, while MAMA-2 (2:1:2:2), with 83.57±1.93 and 164.23±1.93, gave comparable survival except at 170 mg/kg with 60 % survivors for 12 days. MAMA-1 and MAMA-2 were the best curative formulations with MAMA-1 giving additional prophylactic activity. MAMA-3 (2:2:2:1) with 98.70±0.91 and 220.17±0.91, gave comparable (p>0.05) survival at 85 mg/kg with 60 % survival for 13.2 days and significantly higher survival at 42.5 mg/kg for 17 days with 40 % survival. Both MAMA and MAMA-3 were the best chemosuppressive formulations plus additional curative activities. MAMA-4 (1:1:2:2), the best prophylactic formulation with 94.87±2.43 and 201.20±2.43 gave significantly higher (p<0.05) survival at all doses except at 21.25 mg/kg which gave 60 % survival up to 10 days. Thus, the antimalarial therapy desired, following appropriate diagnosis, whether prophylactic, chemosuppressive or curative would determine which of the MAMA decoction formulations to be prescribed. This phenomenon of formulary optimization may also be applied to other pharmacological activities.

Influence of cowpea variety on the potency and deterrent indices of six plant powders against the seed bruchid, Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae)

Bruchid-induced damage, lethal and deterrent indices of Cymbopogon citratus, Alstonia boonei, Hyptis suaveolens, Azadirachta indica, Loranthus braunii and Lycopersicon esculentum were investigated on Oloyin and IT845-2246 cowpea varieties at 0.00, 0.625, 1.25, 2.50 and 5.00% (w/w) under laboratory conditions (29 ± 3 °C and 65 ± 5% R.H.). The experiment was laid out in 6 × 5 × 2 factorial arrangement fitted into a completely randomised design with four replicates. Results showed that irrespective of cowpea variety, the lowest bioactive concentration at which adult bruchid emergence was significantly deterred was 1.25%. A hundred percent mortality was recorded with H. suaveolens at 1.25% concentration with Oloyin, and with C. citratus and A. boonei at 2.50 and 5.00. The powders also caused outright inhibition and reduction in adult bruchid emergence in the third filial generation. For H. suaveolens and C. citratus, lethal concentrations (LC50) were 0.073 and 0.080 on Oloyin and IT845-2246, respectively. Also, C. citratus and A. indica had the highest oviposition deterrence DC50 values, 1.42 and 1.68. Results showed that bioactivity which was lower on Oloyin compared to IT845-2246, depended on cowpea’s accession used and was not dose-dependent. Powders of any of the tested plant species may be effectively exploited for bruchid control in stored cowpea grains at reduced concentration of 1.25% provided.

Antimicrobial and Phytochemical Properties of Alstonia Boonei Extracts

Alstonia boonei De wild is a major spice crop grown abundantly in Ghana and other tropical countries. In this study we have carried out phytochemical analysis and antimicrobial investigation of ethanol and aqueous extracts of the root of Alstonia boonei against a panel of clinically significant bacterial and fungal strains. Four Gram positive and Gram negative bacteria namely Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus were subjected to test the antimicrobial activity along with one fungi namely, Candida albicans. The ethanol and aqueous extracts of root of Alstonia boonei were subjected to microbial susceptibility assays using agar well diffusion method. Phytochemical screening was done to test the presence of phytochemicals responsible for the antimicrobial potential of roots of Alstonia boonei. The results of the phytochemical studies revealed the presence alkaloids, cyanogenetic glycosides, flavonoids, terpenoids and steroids and saponins. Susceptibility testing by disc diffusion assay revealed significant antimicrobial activity of methanol and aqueous extracts of the roots against the pathogens tested. The minimum inhibitory concentrations (MIC) of the various extracts by Agar Dilution method ranged from 3.0 to 10.0 mg/ml. The ethanol extracts exhibited better antimicrobial activity than aqueous extract. The study findings provide supportive evidence for the use of Alstonia boonei in traditional medicines.

Particle Sizes and Thermal Insulation Properties of Some Selected Wood Materials for Solar Device Applications

This study investigates the thermal properties of some selected wood materials found in the rain forest of South Western Nigeria. These wood species are Alstonia boonei (Ahun), Pterygota macrocarpa (Oporoporo), Milicia excels (Iroko), Pterocarpus (Osun), Celtics zenkeri (Ita) and Pterocarpus mildraedii (Ure). Particle sizes of 300 µm, 600 µm and 850 µm were sieved out from each of the different wood materials of the six varieties of wood species. The samples were machined to appropriate disc shape using fabricated hydraulic-press mould. The modified Lee's disc apparatus was used to determine the thermal conductivities of the samples. The result shows that thermal conductivity of the selected wood shavings change with particle sizes. Except for the Pterygota marcrocarpa, other samples had least thermal conductivity values at 600 µm particle size ranging from 0.045-0.067 Wm -1 K -1 . This range fall within the thermal conductivity values of commonly used solar flat plate collectors. In addition, 600 µm pose the best insulation among the particle sizes considered. Hence, the selected wood materials could be used as industrial insulators as their thermal conductivity values fall within the range of existing industrial thermal insulators. The materials could also serve as good potential devices as heat resistant. Keyword: Thermal conductivity, Particle size, Lee's disc, Industrial insulator