Nigerian Ethnomedicine Research Articles

Turmeric-Black Cumin Essential Oils and Their Capacity to Attenuate Free Radicals, Protein Denaturation, and Cancer Proliferation.

Turmeric rhizomes (Curcuma longa) and black cumin seeds (Nigella sativa) are polyherbal ingredients used for the management of cancer and other chronic inflammatory diseases in Nigerian ethnomedicine. Previous studies have shown the antioxidant, anti-inflammatory, and anticancer activities of the individual plant extracts. However, the two spices have not been biologically potentiated in their combined form. Therefore, this study obtained essential oils (EOs) from the combined spices and evaluated their inhibitory effects on free radicals, protein denaturation, and cancer proliferation. The EOs were extracted by hydro-distillation (HD) and characterized by gas chromatography-mass spectrometry (GC-MS). In vitro antioxidant assessment was conducted based on DPPH, hydrogen peroxide (H2O2), nitric oxide (NO), and ferric ion (Fe3+) radical scavenging assays. The cytotoxicity of the oil against non-tumorigenic (HEK293) and cancerous (HepG2 and HeLa) cell lines was determined following the MTT cell viability assay. An in silico molecular docking analysis of the oil constituents was also performed. Six batches of EOs I-VI were afforded, comprising twenty-two major constituents, with aromatic Ar-turmerone being the most prominent compound. There was a marked improvement in the bioactivity of the oils upon repeated HD and as a combination. The batch VI oil exhibited the best activity, with a cytotoxicity (CC50) of 10.16 ± 1.69 µg/100 µL against the HepG2 cell line, which was comparable to 5-fluorouracil (standard, CC50 = 8.59 ± 1.33 µg/100 µL). In silico molecular docking suggested δ-curcumene, Ar-curcumene, Ar-turmerol, and Ar-turmerone among the promising compounds based on their high binding energy scores with NOX2, NF-κB, and mdm2 proteins. In conclusion, the oils from the turmeric-black cumin combined possess a considerable inhibition ability against free radicals, protein denaturation, and cancer proliferation. This study's findings further underscore the effectiveness of turmeric-black cumin as a polyherbal medicinal ingredient.

Modulation of cadmium induced haematological and renal damages by ethanol leaf extract of Pterocarpus mildbraedii in male Wistar rats

The leaf of Pterocarpus mildbraedii is a popular vegetable in Nigerian ethnomedicine, where it is applied in the management of various disorders. This study was carried out to investigate the ameliorative potential of ethanol leaf extract of P. mildbreadii on cadmium induced haematological and renal damages in male Wistar rats. The leaf extract and the toxicant were administered orally to four groups of rats at doses of 400 mg/kg and 10 mg/kg body weight respectively for 14 days. Indices of renal function (serum urea, creatinine, sodium and potassium) and haematological parameters were analyzed using standard methods. Cadmium caused a significant increase (p < 0.05) in the concentrations of urea, creatinine, sodium and potassium. It also caused a significant (p < 0.05) decrease in haematological parameters such as Hb, HCT, RBC, MCV, MCHC, lymphocytes and platelets while the levels of WBC, neutrophils and monocytes increased compared to control. Ethanol leaf extract of P. mildbreadii reversed the cadmium induced alterations in haematological and renal indices. Histological observation of the kidney tissue revealed abnormal histological architecture in animals intoxicated with cadmium. Animals treated with leaf extract of P. mildbreadii did not show any damage in histology of the kidney tissue. These results suggest the ameliorative potentials of leaf extract of P. mildbreadii on haematological and renal disorders in the rats.

GC-MS Identification of Cholinesterase Inhibitory and Antioxidant Molecules from Leaves of Cnidoscolus aconitifolius (Miller) I.M. Johnston (Euphorbiaceae)

Backgound: Alzheimer’s disease (AD) is a progressive and fatal neurodegenerative disease, clinically characterized by memory and cognitive dysfunction. AD affects about 35 million people worldwide today and is estimated to nearly double every 20 years. Cnidoscolus aconitifolius (Miller) I.M. Johnston has been reported in Nigerian ethnomedicine as a memory enhancer. There is a lack of scientific evidence to justify the claims. Moreover, there are no effective neurotherapeutic agents available for the treatment of AD; hence the need arises to search for new and more effective agents. Objective: This study aims to evaluate and identify potential molecules with anti-Alzheimer’s and antioxidant potentials from Cnidoscolus aconitifolius leaves. Methods: The air-dried leaves of Cnidoscolus aconitifolius (Miller) I.M. Johnston (PCG/UNN/0267) were extracted using the successive extraction procedure based on increasing the polarity of the eluent in the ascending order of n-hexane, ethyl acetate, and methanol. Phytochemical screening was carried out on the extracts using standard procedures. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities were done according to Ellman’s method. Eserine was used as standard. Antioxidant potentials were evaluated using standard in vitro chemical analyses. A GC-MS (QP2010SE, SHIDMAZU JAPAN) analysis was done to identify bioactive compounds from the most active fraction. Statistical analyses were performed using one-way ANOVA followed by Dunnett’s Multiple Comparison test at α0.05. Results: Phytochemical analysis revealed the presence of tannins, resins, saponins, flavonoids, phenols, carbohydrates, alkaloids, and terpenoids. Ethyl acetate fraction demonstrated the highest acetylcholinesterase and butyrylcholinesterase inhibitory activity at 1 mg/mL with IC50 values of 0.288 ± 0.00 mg/mL (82.9% inhibition) and 0.440±0.02 mg/mL ((75.4% inhibition), respectively, compared to eserine (IC50=0.050 ± 0.01 mg/mL) for AChE and (IC50=0.049 ± 0.00 mg/mL) for BuChE. Metal (ferrous ion) chelating activity was also high in the ethyl acetate fraction with IC50 value of 0.160 ± 0.00 mg/mL compared to EDTA (IC50 = 0.085 ± 0.00 mg/mL) at 1 mg/mL. Hydroxyl radical scavenging activity was higher in the ethyl acetate fraction (IC50 = 0.352 ± 0.01 mg/mL) when compared to BHT (IC50 = 0.074 ± 0.00 mg/mL) at 1 mg/mL. The pro-anthocyanidin content was also higher in ethyl acetate (6.94 ± 0.16 mg cyanidin/g of sample) compared to other fractions. GC-MS analysis of the most active fraction (ethyl acetate) revealed a total of 56 compounds. The major compounds revealed were: n-Hexadecanoic acid (Area % of 13.45%; Retention time of 14.863), Phytol (Area % of 5.13%; Retention time of 15.864), Octadecanoic acid (Area % of 4.86%; Retention time of 16.211), 9, 12, 15-Octadecatrienoic acid (Z,Z,Z) (Area % of 26.85%; Retention time of 16.09), Squalene (% Area of 2.65%; Retention time of 20.94) and alpha-Tocopheryl acetate (% Area of 1.71%; Retention time of 23.40). Conclusion: C. aconitifolius has the potential to inhibit cholinesterase enzymes involved in the pathology of Alzheimer’s disease. The molecules identified could serve as potential drug leads in managing Alzheimer’s disease.

Cytotoxic action of the leaves of Uvaria chamae P.Beauv. and Dicliptera paniculata (Forssk.) I.Darbysh. from Nigeria mediated through intrinsic apoptotic pathway induction in four cancer cell lines

BackgroundOver the years, the morbidity and mortality due to cancer have continued to increase worldwide. Plants are well utilized in Nigeria ethno-medicine for cancer treatment. However, scientific evidence, particularly at the molecular level, has been lacking, and biodiversity loss is a threat. Aim of the studyThe cytotoxic activity of the leaves of six plants used in Nigeria ethno-medicine was investigated and the molecular pathway of cytotoxic action of two active extracts on four cancer cell lines (A549, RD, MCF-7, and HeLa) was also assessed. Materials and methodsCytotoxic activities of the plant extracts were assessed on breast (MCF-7), lung (A549), cervical (HeLa), adenocarcinoma and rhabdomyosarcoma (RD) cells using MTT cell viability assay in a time-dependent manner. The sandwich ELISA method was used to assess the protein expressions (Bcl-2, BAX, and executioner caspase 3) involved in the apoptotic pathway in cancer cells after treatment with cytotoxic extracts. UHPLC-MS/MS approach was used to analyze the possible bioactive phytochemicals of the cytotoxic plant extract. ResultsUvaria chamae and Dicliptera paniculata extracts displayed good cytotoxicity across all cell lines in a time- and concentration-dependent manner (CC50 <30 µg/mL). Increased pro-apoptotic BAX and lowered expression of anti-apoptotic Bcl-2 show the cytotoxic action of the two extracts followed the intrinsic apoptotic pathway compared to untreated cells. The increased expression of executioner caspase 3 indicated that the intrinsic apoptotic pathway was caspase-dependent. ConclusionThe anticancer potential of U. chamae and D. paniculata in this study validates the use of these plants in Nigerian ethno-medicine, highlighting apoptosis as a molecular pathway of their cytotoxicity.

Bioactivity-guided isolation of the antidiabetic principle in Pterocarpus Santalinoides leaf extract

Pterocarpus santalinoides is used in Nigerian ethnomedicine to treat diabetes mellitus. This study aimed to establish the antidiabetic property of the plant, and isolate and characterize its active principle. Dried and pulverized leaves (500 g) of P. santalinoides were extracted with 1.8 L of 80 % hydromethanol by cold maceration. The dried extract (10 g) was partitioned into n-hexane, ethyl acetate (EtOAc), n-butanol, and water. Antidiabetic activitiy-guided isolation by column chromatographic separation of the EtOAc soluble and purification of the sub-fractions by repeated preparative thin layer chromatography (pTLC) yielded a C-glycosyl flavonoid, identified as isovitexin. The chemical structure was elucidated based on high-resolution mass spectroscopy, 1D, and 2D nuclear magnetic resonance spectroscopic analyses. Alloxan-induced diabetic rat model was adopted for antidiabetic screening. The extract of P. santalinoides (100-200 mg/kg), fraction F4 (50 mg/kg), sub-fraction F4.3 (10 mg/kg), and the semi-purified compound F4.3.2 (5 mg/kg) significantly (p<0.05) reduced the fasting blood glucose of alloxan-induced diabetic rats, causing 48.4, 69.4, 57.7 and 64.5 % antidiabetic activity respectively, compared with > 68 % recorded in glibenclamide (2 mg/kg) control. These results reveal that isovitexin is the antidiabetic principle in P. santalinoides.

Assessment of antimalarial medicinal plants used in Nigerian ethnomedicine reveals antimalarial potential of Cucurbita pepo leaf extract

Medicinal plants are often used to treat malaria in different parts of Nigeria and exploiting these can unravel new therapeutic leads. This study evaluated the antiplasmodial potential of selected plants used to treat malaria in Nsukka, Enugu state, Nigeria. Leaves of three different plants (Cucurbita pepo, Hibiscus rosa-sinensis and Pennisetum purpureum) were collected for screening and two extracts viz., 70%v/v ethanol and dichloromethane/methanol (1:1 v/v), were prepared for each. An acute toxicity test was done in mice and cytotoxicity was assessed using human hepatoma cell line (HUH). The extracts were screened against chloroquine-sensitive P. falciparum (Pf3D7) in vitro, and chloroquine-resistant P. berghei ANKA in vivo using a 4 day-suppressive test in mice. Cucurbita pepo ethanol extract was further tested for hemolytic effect on human erythrocytes and in established infection in mice. Parameters assessed were post-treatment parasitemia, hematological indices, organ (brain, kidney, liver, and spleen) weights, and survival. The extracts were non-cytotoxic up to a test dose of 100 μg/ml and 2000 mg/kg fed - mice did not show acute or delayed toxicity. Cucurbita pepo ethanol extract (CpE) displayed excellent in vitro antiplasmodial activity with IC50 of 3.05 μg/ml. At an oral dose of 500 mg/kg, mice were observed to display significant (p < 0.01) ∼51% suppression of parasitemia. The extract did not produce any significant hemolytic effect up to a test concentration of 1 mg/ml. In established infection, a dose of 300 mg/kg significantly (p < 0.01) protected mice from anemia caused by low hematocrit. The extract produced significant (p < 0.05) elevation in red blood cells and platelet counts, and an increase in hemoglobin was evident at 100 and 300 mg/kg. Further, CpE in a dose-dependent manner, reversed liver and spleen weight increase seen in untreated, infected mice. These findings show C. pepo as a potential candidate for further studies to identify its bioactive principle(s) and possible mechanism(s) of antimalarial action.

Bioassay-guided isolation of cytotoxic constituents of Aframomum melegueta K.Schum. seeds

The seeds of Aframomum melegueta are used extensively in the Nigerian ethnomedicine for the management of cancer. This study therefore aimed at isolating and characterizing its cytotoxic constituents. Methanol extract of the seed was obtained through cold maceration, and it was further partitioned into n – hexane, dichloromethane and ethylacetate. The most active fraction was purified on repeated chromatographic techniques, using vacuum liquid chromatography (VLC), column (CC), and high-performance liquid chromatography (HPLC). The extract, purified fractions and isolated compounds were tested for their cytotoxic activities against the human Rhabdomyosarcoma (RD) and breast (MCF-7) cancer cell lines, using MTT assay. The crude extract and n-hexane fraction were found to be selectively cytotoxic to the cancer cell lines. Bioassay-guided fractionation of the n-hexane fraction led to the isolation of three compounds, which were identified as 6-shogaoal, 6-paradol, and 1-dehydro-6-gingerdione. 6-shogaoal demonstrated the highest cytotoxicity with CC50 values of 0.11 ± 0.02 and 0.25 ± 0.05ìg/mL against RD and MCF-7 cell lines respectively, and these were higher in activity when compared with cyclophosphamide (CC50 = 1.98 ± 0.15 and 0.71 ± 0.7ìg/mL). The presented data validates the ethnomedicinal use of A. melegueta in the treatment of cancer and is also indicative of the potential of 6-shogaol as an anticancer agent.

Ethnobotanical Survey of Plants used for Cancer Treatment in Akinyele Local Government of Ibadan, Nigeria and Preliminary Cytotoxic Activity of Selected Plants

Background: In Nigerian ethnomedicine, a few anticancer constituents of medicinal plant of natural products have been reported in the literature. Although several traditional medical practitioners (TMPs) have claimed to have managed this disease with plants that have been in existence from ancient times.Objective: This study aimed at the documentation and validation of plants that are commonly used in the treatment of cancer in Akinyele Local Government of Oyo State, Nigeria.Materials and methods: Focus-Group discussion and administration of semi-structured questionnaires were used to discover the practice of traditional medicine using plants. The methanol extracts of the commonly cited plants were then screened for cytotoxicity using the Brine shrimp lethality (BSL) and in vitro [3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay. Two cancer (Rhabdomyosarcoma; RD and cervical; Hep-2C) and normal (Vero) cell lines were used for the screening of the extracts.Results: A total number of 45 Traditional Medical Practitioners and herb sellers were recruited for this study, 26 different plants were recorded with their local names and parts used for therapeutic preparation. Two plant extracts; Aframomum melegueta and Strophanthus hispidus were found to be active against the cancer cell lines and selective to normal cell line used.Conclusion: Some of the plants had cytotoxic properties on the cancer cell lines which supports the claims of the Traditional Medicinal Practitioners. However, the non-selectivity of some plants to normal cells could be a great threat to the cancer patients being treated.

Isolation and identification of phytochemical constituents from the roots of Calliandra portoricensis

Calliandra portoricensis is a plant widely used in Nigerian ethnomedicine for the treatment of tuberculosis and other respiratory conditions. In view of its traditional use, the present study is aimed at the isolation and identification of bioactive components or secondary metabolites which may be responsible for its biological activity. The air dried roots was extracted with hexane, ethyl acetate and then methanol via maceration at roomtemperature. Repeated column chromatography of the ethyl acetate extract over silica gel yielded linalonic acid, spinasterone, lupeol, daucosterol and triacontanyl caffeate. The structures of these compounds were determined by NMR, mass spectrometry and comparison with literature. This is an initial report of these compounds from the plant material.&#x0D; Key words: Linalonic acid, Triacontanyl caffeate, Daucosterol, Spinasterone, Nigeria

Antioxidant and Antimicrobial Studies of Some Hemi-parasitic West African Plants

The study investigated the antioxidant and antimicrobial activities of some West African hemi-parasitic plants, which comprised Tapinanthus bangwensis (TB), Tapinanthus globiferus (TG) and Globimetula braunii (GB), used in Nigerian ethnomedicine for the management of skin and other microbial infections. This was with a view to determining the most active plant extract and fraction. The leaf and stem of each plant was separately air-dried, powdered and macerated in ethanol-H20 (8:2). The extracts were subjected to in vitro antioxidant tests such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), Fe2+ chelating ability (FIC) and total antioxidant capacity (TAC) assays, with L-ascorbic acid, quercetin and ethylenediaminetetraacetic acid (EDTA) as positive controls. The antimicrobial test was carried out using micro-broth dilution method against reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, where ciprofloxacin and ketoconazole were the positive controls. An activity-guided fractionation approach was adopted in the study. The most active GB leaf extract was fractionated to obtain n-hexane, dichloromethane, ethylacetate, n-butanol and aqueous fractions, and were subsequently tested. The results showed that the extract of GB leaf demonstrated the highest bioactivities with inhibitory concentration (IC50) of DPPH at 31.21±1.11 µg/mL, FRAP value of 109.30±0.76 mg AAE/g, TAC value of 178.15±3.54 mg AAE/g and MIC of 5.0 – 10.0 mg/mL. The Ethylacetate fraction of GB leaf demonstrated the highest bioactivities, which were four-times, thrice and twice better than its GB leaf extract in the DPPH, TAC and antimicrobial studies respectively. The EtOAc fraction (IC50 = 8.58±1.39 µg/mL) was comparable (P &gt; 0.05) in antioxidant activity with quercetin (IC50 = 7.72±0.88 µg/mL). The EtOAc fraction also exhibited broad-spectrum antimicrobial activity with inhibitory concentration of 1.25 mg/mL against MRSA and C. albicans. In conclusion, the extract of G. braunii leaf demonstrated considerable bioactivities and the moderately polar EtOAc fraction was the most active fraction; hence, validates the folkloric use G. braunii leaf as a remedy for microbial infections.

Aqueous extract of Moringa oleifera leaf used in Nigerian ethnomedicine alters conception and some pregnancy outcomes in Wistar rat

The leaf of Moringa oleifera (Lam) Moringaceae, is globally accepted in ethnomedicine and particularly used to tackle malnutrition and enhance breast milk production in resource-limited settings. It is reported to be laden with a wide array of interesting bioactive plant metabolites. However, its safety at conception and during pregnancy has not been well reported notably in Nigeria. This work investigated the in vitro and in vivo uteroactive and contraceptive potentials of cold and hot aqueous extracts of M. oleifera leaves (MOL) commonly used in Nigerian Traditional Medicine. In addition, we determined the physicochemical characteristics of the freeze-dried aqueous extracts and powder.Powdered MOL (100 g each, 1:10 w/v) was extracted in the cold (room temperature) and hot (boiling) distilled water. The in vitro protocol involved the dose-dependent effect of aqueous extracts of MOL on the tension produced by the isolated uteri of non-pregnant rats using organ bath. Uterine contractility and contraceptive properties of MOL were assessed in vivo using female Wistar rats (150–170 g). Particle morphology, size, polydispersity index and zeta potential of MOL were determined.The in vitro administration of cold and hot aqueous extracts of MOL significantly (p < .05) produced uterine contractility with varying intensities. Contractile effect of cold MOL aqueous extract (89.7%) was higher than that of hot MOL (50.6%). In vivo, MOL cold aqueous extracts administered before and after mating, respectively produced 100% and 80% inhibition of conception, while 96.6% and 58% effect was comparatively produced by hot aqueous extracts of MOL.This work has provided useful data on MOL, a commonly consumed medicinal preparation/food supplement and the possible implications of its intake before conception, at conception and during pregnancy.

Resveratrol derivatives from Commiphora africana (A. Rich.) Endl. display cytotoxicity and selectivity against several human cancer cell lines.

Commiphora africana (A. Rich.) Endl. (Burseraceae) is a medicinal plant widely used in Nigerian ethnomedicine. The in vitro cytotoxicity of the stem bark extract of C.africana and isolated cytotoxic compounds was investigated. Three resveratrol derivatives: (E)-resveratrol 3-O-rutinoside (1), 5-methoxy-(E)-resveratrol 3-O-rutinoside (2), and pinostilbene (3), together with 3-hydroxy-5-methoxybenzoic acid (4) were isolated from the methanol fraction of C.africana. Their structures were determined by extensive analysis of their HREIMS and NMR spectra. The cytotoxicity of the isolated compounds against four human carcinoma cells was determined using the MTT assay. Compound 1 displayed the highest antiproliferative effect on the cell lines, with IC50 values of 16.80, 21.74, 17.89, and 17.44μM, against MCF7, A549, PC3, and HepG2 human cancer cell lines, respectively. In addition, compounds 1-3 showed low toxicity against normal human prostate cell line, with selectivity indices greater than five across the carcinoma cells, indicating that the compounds possess potential in the development of low-toxicity chemotherapeutic agents. These results support the traditional use of this plant in the treatment of cancer.

In vitro cytotoxic activity of medicinal plants from Nigeria ethnomedicine on Rhabdomyosarcoma cancer cell line and HPLC analysis of active extracts

BackgroundCancer is a leading cause of death world-wide, with approximately 17.5 million new cases and 8.7 million cancer related deaths in 2015. The problems of poor selectivity and severe side effects of the available anticancer drugs, have demanded the need for the development of safer and more effective chemotherapeutic agents. The present study was aimed at determining the cytotoxicities of 31 medicinal plants extracts, used in Nigerian ethnomedicine for the treatment of cancer.MethodsThe plant extracts were screened for cytotoxicity, using the brine shrimp lethality assay (BSLA) and MTT cytotoxicity assay. Rhabdomyosarcoma (RD) cell line, normal Vero cell line and the normal prostate (PNT2) cell line were used for the MTT assay, while Artemia salina nauplii was used for the BSLA. The phytochemical composition of the active plant extracts was determined by high performance liquid chromatography (HPLC) analysis.ResultsThe extract of Eluesine indica (L.) Gaertn (Poaceae), with a LC50 value of 76.3 μg/mL, had the highest cytotoxicity on the brine shrimp larvae compared to cyclophosphamide (LC50 = 101.3 μg/mL). Two plants extracts, Macaranga barteri Mull. Arg. (Euphorbiaceae) and Calliandra portoricensis (Jacq.) Benth (Leguminosae) exhibited significant cytotoxic activity against the RD cell line and had comparable lethal activity on the brine shrimps. Further cytotoxic investigation showed that the dichloromethane fraction of Macaranga barteri (DMB) and the ethyl acetate fraction of Calliandra portoricensis (ECP), exhibited approximately 6-fold and 4-fold activity, respectively, compared to cyclophosphamide on RD cell line. Determination of selective index (SI) using Vero and PNT2 cell line indicated that DMB and ECP displayed a high degree of selectivity against the cancer cell under investigation. HPLC analysis showed that 3,5dicaffeoylquinic acid, acteoside, kampferol-7-O-glucoside and bastadin 11 were the major components of DMB while the major components of ECP were neurolenin B, nigrosporolide and trans-geranic acid.ConclusionThe results demonstrate the cytotoxicity of Macaranga barteri and Calliandra portoricensis extracts, which are used in Nigerian folklore for cancer treatment.

Protective effects of Buchholzia coriacea seeds extract and fractions on blood glucose and hyperlipidemia in diabetic rats

Background: The Buchholzia coriacea seeds (Capparaceae) are used in Nigerian ethnomedicine for treatment of hyperglycemia. Our aim, therefore, is to evaluate antihyperglycemic and hypolipidemic effects of extract and fractions of Bulcholzia coriacea seeds.Methods: The cut, dried and pulverized seeds were extracted with a mixture of methanol-dichloromethane (1:1) which yielded the crude extract, MDE. The MDE was fractionated using bioactive guided procedure and yielded hexane fraction (HF), ethylacetate fraction (EF) and methanol fraction (MF). Alloxan-induced diabetes, normoglycemic test and oral glucose tolerance test (OGTT) were the antidiabetic models employed, while hypolipidemic study was performed using standard assay kits to determine the serum total cholesterol (TC) triglycerides (TG) and low density lipoproteins (LDL). Acute toxicity test of the extract was performed using Lorke’s method while qualitative and quantitative phytochemical analyses were also performed using standard procedures.Results: The results showed an oral median lethality dose (LD50) greater than 5000mg/kg. The extract and fractions showed significant antihyperglycemic effect comparable and in synergy to metformin, a standard agent. The extract (200mg/kg) showed the highest percentage blood glucose reduction (PBGR) of 52.89% while ethylacetate fraction (EF, 400mg/kg) showed PBGR of 50.84%. Also, the MDE and hexane fraction (HF) showed a significant reduction of TC, TG and LDL and related increase in HDL-C levels in diabetic treated rats.Conclusions: The extract and the fractions of Buchholzia coriacea seeds possess antihyperglycemic and antihyperlipidemic effects and showed same mechanism of action as metformin, thus providing scientific rationale for its folkloric use.

Establishing some pharmacognostic standards for Nigerian &lt;i&gt;Musa x sapientum&lt;/i&gt; L. leaf

Musa x sapientum is well known to Nigerian ethnomedicine and widely cultivated worldwide for its fruit. All the parts have medicinal application. The leaves collected from Abuja, Ibadan, Yenagoa and Owerri, Nigeria were subjected to microscopical examination and physic-chemical experiments in order to provide some pharmacognostic standards for it. The leaf possessed epidermal cells with straight anticlinal walls, bearing fewer stomata on the upper surface than the lower surface that showed numerous anomocytic stomata. The moisture content was (7.6% and 13.0%), water and ethanol soluble extractives (7.9% - 9.5% and 5.9% - 7.3%, respectively), total ash (5.5% - 14.0%), acid insoluble (0.5% - 2.7%) water soluble extractive (3.3% to 7.2%), sulphated ash (4.3% - 8.2%), stomata number and stomata index were 14 ± 0.80 and 16.00 ± 0.76, respectively. This will help to detect adulteration of the powdered sample.Keywords: Adulteration; Standardization; Musa sapientum; Monograph

Sub-chronic Effect of Methanol-Dichloromethane Stem Bark Extract of Stemonocoleus micranthus Harms. (Fabaceae) on Lipid Profile and Histology of Liver and Kidney of Rats

In Nigerian ethnomedicine, Stemonocoleus micranthus Harms (Fabaceae) is used in the management of heart related diseases. This study investigated the effect of sub-chronic administration of methanol-dichloromethane stem bark extract of S. micranthus (SME) on lipid profile and histology of liver and kidney of rats. Adult albino rats of both sexes were randomly divided into four groups (n=5) and received daily administration of SME (100, 200, and 400 mg/kg) and 2 ml/kg distilled water (control) respectively for 28 days per oral. Biochemical tests were performed pre-treatment and subsequently fortnightly as the treatment commenced. The results showed that the extract increased the serum high density lipoprotein cholesterol concentration while low density lipoprotein cholesterol, total cholesterol, triacylglycerol, and very low density lipoprotein cholesterol concentrations were reduced compared with the baseline values. However, the histopathological examination of the liver and kidney of the rats that received extract and solvent revealed normal portal area with bile ducts and hepatic artery as well as normal glomerulus and renal tubules without observable changes suggesting zero tendency of causing toxic effects. The preliminary phytochemical analysis showed that SME contained alkaloids, glycosides, flavonoids, reducing sugars, terpenoids, saponins, proteins and, fats oils. SME exhibited an oral LD50 >5 g/kg in mice. These findings suggest that the stem bark extract of S. micranthus contains constituents that possess hypolipidemic activity in rats.

Alpha-amylase Inhibition and Brine Shrimp Lethality Activities of Nine Medicinal Plant Extracts from South-West Nigerian Ethnomedicine

ABSTRACTAcanthospermum hispidum, Alchornea laxiflora, Calyptrochilum christyanum, Heliotropicum indicum, Holarrhena floribunda, Ipomoea asarifolia, Nauclea diderrichii, Piper guineense, and Tetracera scandens were extracted into methanol and screened for the availability of alpha-amylase inhibitors. Plant extracts’ toxicity was determined by brine shrimp lethality assay (BSLA). The most active plant, Nauclea diderichii, was fractionated into four solvent systems (n-hexane fractions, ethyl acetate, dichloromethane, and n-butanol) and tested. All the extracts showed varying degrees of alpha-amylase inhibitory activity. N. diderrichii with IC50 = 248.30 ± 0.27 µg.mL–1 had the highest inhibitory activity, while its butanol fraction with IC50 = 137.8 µg.mL–1 had activity comparable to the standard α-amylase inhibitor acarbose (IC50 = 177.50 ± 0.42 µg.mL–1). LC50 values for BSLA ranged from 11.35 to 1,127.50 µg.mL–1, with T. scandens being the most toxic with 11.35 µg.mL–1 and N. diderrichii the least toxic with 1,127.50 µg.mL–1.

Cholinesterase inhibitory activity and structure elucidation of a new phytol derivative and a new cinnamic acid ester from Pycnanthus angolensis

The leaves of Pycnanthus angolensis (Welw.) Warb., Myristicaceae, are used as memory enhancer and anti-ageing in Nigerian ethnomedicine. This study aimed at evaluating the cholinesterase inhibitory property as well as isolates the bioactive compounds from the plant. The acetylcholinesterase and butyrylcholinesterase inhibitory potentials of extracts, fractions, and isolated compounds were evaluated by colorimetric and TLC bioautographic assay techniques. The extract inhibited both enzymes with activity increasing with purification, ethyl acetate fraction being most active fraction at 65.66±1.06% and 49.38±1.66% against acetylcholinesterase and butyrylcholinesterase, respectively while the supernatant had 77.44±1.18 inhibition against acetylcholinesterase. Two new bioactive compounds, (2E, 18E)-3,7,11,15,18-pentamethylhenicosa-2,18-dien-1-ol (named eluptol) and [12-(4-hydroxy-3-methyl-oxo-cyclopenta-1,3-dien-1yl)-11-methyl-dodecyl](E)-3-(3,4-dimethylphenyl)prop-2-enoate (named omifoate A) were isolated from the plant with IC50 of 22.26μg/ml (AChE), 34.61μg/ml (BuChE) and 6.51μg/ml (AChE), 9.07μg/ml (BuChE) respectively. The results showed that the plant has cholinesterase inhibitory activity which might be responsible for its memory enhancing action, thus justifying its inclusion in traditional memory enhancing preparations

Antimalarial and cytotoxic properties of Chukrasia tabularis A. Juss and Turraea vogelii Hook F. Ex. Benth

Malaria, caused by plasmodium parasite, is at the moment the highest cause of morbidity and mortality in the tropics. Recently, there is increasing efforts to develop more potent antimalarials from plant sources that will have little or no adverse effects. This study is aimed at investigating the in vivo mice antimalarial and in vitro antiplasmodial effects of two Meliaceae plants commonly used in Nigerian ethnomedicine as part of recipe for treating malaria infection: Chukrasia tabularis and Turraea vogelii. Hot water decoction and methanol extract of both plants were evaluated for their antimalarial activity in vivo using the mice model assay and in vitro using the parasite lactate dehydrogenase (pLDH) assay. The extracts were also assessed for toxicity with brine shrimp lethality assay and in mammalian cell lines using the neural red assay. The in vivo mice model antimalarial study showed that the methanol extract of the stem bark of C. tabularis exhibited the highest % chemosuppression (83.65 ± 0.66) at the highest dosage administered (800 mg/kg) when compared with chloroquine diphosphate, the standard reference drug which had a % suppression of 90.36 ± 0.04 (p < 0.05). The in vitro antiplasmodial study indicated that the aqueous extract of the stem bark of C. tabularis displayed good activity against Plasmodium falciparum chloroquine-sensitive (D6) strain (IC50 of 10.739 μg/mL) and chloroquine-resistant (W2) strain. Chloroquine and artemisinin had <0.163 and <0.0264, respectively.

English

Chemical investigation into the composition of Cissus polyantha tuber, a plant used in Northern Nigerian ethno medicine for managing inflammatory conditions and conjunctivitis has led to the isolation of a chalcone from the ethyl acetate and a steroid from the hexane soluble fractions of its methanol extract. The structures of these compounds were elucidated by extensive analysis of their spectroscopic data, including 1 and 2D nuclear magnetic resonance (NMR). This is the first report of the isolation of the compounds from the plant and they may be responsible for the previously reported anti-inflammatory effects. &nbsp;&nbsp;&nbsp; Key words: Cissus polyantha, vitaceae, 2D nuclear magnetic resonance (NMR), chalcone, steroid. &nbsp;&nbsp