Ethnobotanical study of wild edible plants in Dibatie district, Metekel zone, Benishangul Gumuz Regional State, western Ethiopia.

BACKGROUND: Plants deliver livelihood and food for millions of people in the world. Indeed, wild edible plants support rural communities in developing countries to overcome seasonal unfavorable conditions. In rural areas of Ethiopia, wild edible plants play an indispensable role in fighting food insecurity as emergency or supplementary foods. Hence, this research was aimed at studying the ethnobotanical assessment of wild edible plants in Dibatie district, Metekel zone, western Ethiopia. METHODS: Ethnobotanical data was collected using a semi-structured interview, field observation, focus group discussions, a market survey, and the ranking of selected plants. Besides, voucher specimens were collected and stored at the National Herbarium of Ethiopia. Descriptive statistics, preference ranking, direct matrix ranking, and familiarity index were computed for data analysis. RESULTS: This study has documented 54 wild edible plant species belonging to 33 plant families and 46 genera. Of these, most (38.90%) had tree growth habits. Wild edible plants bear mostly fruits (72.20%) as edible parts. Local people usually consume these plants freshly raw as complementary foods, though some wild edibles require processing. They were mostly harvested in the January (31.48%) and May (27.78%) months, with the least collected in September (7.41%). Most wild edible plants (78.57%) were available in uncontrolled habitats, while others (21.43%) live in farmlands, home gardens, and as live fences. Out of the recorded plants, about 98% had additional uses besides their nutritional values. CONCLUSION: Wild edible plants assist the livelihoods of the local people in food security, agriculture, energy sources, construction, medicines, ecological services, aesthetics, income generation, and household utensils. Nevertheless, wild edible plants are recently threatened due to various anthropogenic factors in the study area. Thus, they need wise use and in-situ and ex-situ conservation measures from all the concerned bodies for sustainable use in the future.

Antidiarrheal coumarins from Psydrax schimperianus (A. Rich.) Bridson roots.

ETHNOPHARMACOLOGICAL RELEVANCE: Psydrax schimperianus (A. Rich.) Bridson. roots are used for the treatment of diarrhea in West Arsi zone, Ethiopia. AIM OF THE STUDY: This study aimed to investigate the in vivo antidiarrheal activity of crude extract and coumarins isolated from the roots of Psydrax schimperianus to provide a pharmacological basis for its traditional use as an antidiarrheal agent in Ethiopia. MATERIALS AND METHODS: The crude root extract of P. schimperianus was tested in vivo for antidiarrheal efficacy in mice utilizing castor oil-induced diarrhea, gastrointestinal transit time, and enteropooling models at doses of 100, 200, and 400 mg/kg. Phytochemical investigation of the crude root extract led to the isolation of two coumarins, isoscopoletin, and scoparone. Isoscopoletin and scoparone were evaluated for antidiarrheal activity against castor oil-induced diarrhea model at 10 mg/kg and 20 mg/kg doses. RESULTS: The crude root extract of P. schimperianus, at doses of 100, 200, and 400 mg/kg, inhibited defecation by 37.5%, 46.2%, and 61.2%, respectively. At a dose of 20 mg/kg, scoparone and isoscopoletin reduced defecation by 61.2% and 66.6%, respectively. CONCLUSION: The study warrants further investigation of isoscopoletin and scoparone towards development as a novel treatment for diarrheal diseases.

Identification of lobetyolin as a major antimalarial constituent of the roots of Lobelia giberroa Hemsl.

Lobelia giberroa Hemsl. is an endogenous Ethiopian medicinal plant with a long history of use in the treatment of malaria, bacterial and fungal diseases, and cancer. Here, we present the in vivo bioassay-guided fractionation of the 80% methanol extract of L. giberroa roots, which led to the isolation of lobetyolin. L. giberroa roots were extracted with 80% methanol, and the dried 80% methanol extract was fractionated with hexane, ethyl acetate, methanol, and water. Acute oral toxicity study was conducted according to the Organisation for Economic Co-operation and Development Guideline 425 by using female Swiss albino mice. Antimalarial activity was assessed in Plasmodium berghei-infected Swiss albino mice. Through in vivo bioassay-guided fractionation processes lobetyolin, a C14-polyacetylene glucoside, was isolated from the methanol fraction by silica gel column chromatography as the main active ingredient from the plant. The chemical structure of lobetyolin was elucidated by interpretation of spectroscopic data (1HNMR, 13CNMR, IR. MS) including two dimensional NMR. The plant extract was considered safe for administration up to 2000 mg/kg. In the four-day suppressive test, the 80% methanol extract (400 mg/kg), methanol fraction (400 mg/kg), and lobetyolin (100 mg/kg) exhibited antimalarial activity, with chemosuppression values of 73.05, 64.37, and 68.21%, respectively. Compared to the negative control, which had a mean survival time of 7 days, the lobetyolin (100 mg/kg) and methanol fraction (400 mg/kg) treated groups had mean survival times of 18 and 19 days, respectively. The current study supports the traditional use of the plant for the treatment of malaria. The structural differences between lobetyolin and existing antimalarials, as well as its previously unknown antimalarial activity, make it of interest as an early lead compound for further chemical optimization.

Antiproliferative Effects of Alkaloids from the Bulbs of Crinum abyscinicum Hochst. ExA. Rich.

Crinum abyscinicum Hochst. ExA. Rich bulb is traditionally used in Ethiopia for the treatment of various ailments including internal parasites, mastitis, rabies, colic diseases of animals, and cancer. Despite its importance in traditional cancer treatment, no research work has been reported on the antiproliferative activity of the bulb extract and its major constituents. Phytochemical investigation of the bulb extract of C. abyscinicum by PTLC over silica gel resulted in the isolation of two alkaloids, which were unequivocally identified as 6-hydroxycrinamine and lycorine on the basis of 1H- and 13C-NMR and MS analysis. The bulb extract, 6-hydroxycrinamine, and lycorine possessed significant antiproliferative activity, lycorine being the most active exhibiting GI50 values of 2.8 µg/ml and 3.4 µg/ml against A2780 and MV4-11 cells, respectively. Cell cycle analysis and annexin V/propidium iodide double staining in A2780 cells revealed that both compounds increased the percentage of cells in the S-phase at 30 µg/ml without inducing apoptosis. Our results suggest that the antiproliferative activities of the bulb extract of C. abyscinicum, 6-hydroxycrinamine, and lycorine could support the traditional claim of the plant against cancer.

Antimalarial Activity of Acetylenic Thiophenes from Echinops hoehnelii Schweinf.

Malaria is one of the world's most severe endemic diseases and due to the emergence of resistance to the currently available medicines, the need for new targets and relevant antimalarial drugs remains acute. The crude extract, four solvent fractions and two isolated compounds from the roots of Echinops hoehnelii were tested for their antimalarial activity using the standard four-day suppressive method in Plasmodium berghei-infected mice. The 80% methanol extract exhibited suppression of 4.6%, 27.8%, 68.5% and 78.7% at dose of 50, 100, 200 and 400 mg/kg respectively. The dichloromethane fraction displayed chemosuppression of 24.9, 33.5 and 43.0% dose of 100, 200 and 400 mg/kg of body weight. Five acetylenicthiophenes were isolated from the dichloromethane fraction of which 5-(penta-1,3-diynyl)-2-(3,4-dihydroxybut-1-ynyl)-thiophene decreased the level of parasitaemia by 43.2% and 50.2% while 5-(penta-1,3-diynyl)-2-(3-chloro-4-acetoxy-but-1-yn)-thiophene suppressed by 18.8% and 32.7% at 50 and 100 mg/kg, respectively. The study confirmed the traditional claim of the plant to treat malaria and could be used as a new lead for the development of antimalarial drugs.

Antidiabetic activity and phytochemical screening of extracts of the leaves of Ajuga remota Benth on alloxan-induced diabetic mice.

BACKGROUND: Ajuga remota Benth is traditionally used in Ethiopia for the management of diabetes mellitus. Since this claim has not been investigated scientifically, the aim of this study was to evaluate the antidiabetic effect and phytochemical screening of the aqueous and 70% ethanol extracts on alloxan-induced diabetic mice. METHODS: After acute toxicity test, the Swiss albino mice were induced with alloxan to get experimental diabetes animals. The fasting mean blood glucose level before and after treatment for two weeks in normal, diabetic untreated and diabetic mice treated with aqueous and 70% ethanol extracts were performed. Data were statistically evaluated by using Statistical Package for the Social Sciences software version 20. P-value <0.05 was considered statistically significant. RESULTS: The medium lethal doses (LD50) of both extracts were higher than 5000 mg/kg, indicating the extracts are not toxic under the observable condition. Aqueous extracts of A.remota (300 mg/kg and 500 mg/kg body weight) reduced elevated blood glucose levels by 27.83 ± 2.96% and 38.98 ± 0.67% (P < 0.0001), respectively while the 70% ethanol extract caused a reduction of 27.94 ± 1.92% (300 mg/kg) & 28.26 ± 1.82% (500 mg/kg). Treatment with the antidiabetic drug, Glibenclamide (10 mg/kg body weight) lowered blood glucose level by 51.06% (p < 0.05). Phytochemical screening of both extracts indicated the presence of phenolic compounds, flavonoids, saponins, tannins, and steroids, which might contribute to the antidiabetic activity. The extracts, however, did not contain alkaloids and anthraquinones. CONCLUSION: The aqueous extract (500 mg/kg) showed the highest percentage reduction in blood glucose levels and the ability of A. remota extracts in reducing blood glucose levels presumably due to the presence of antioxidant constituents such as flavonoids. The effect of the extract supported the traditional claim of the plant.

Survey of Medicinal Plants Used to Treat Malaria by Sidama People of Boricha District, Sidama Zone, South Region of Ethiopia.

In Ethiopia, malaria control has been complicated due to resistance of the parasite to the current drugs. Thus, new drugs are required against drug-resistant Plasmodium strains. Historically, many of the present antimalarial drugs were discovered from plants. This study was, therefore, conducted to document antimalarial plants utilized by Sidama people of Boricha District, Sidama Zone, South Region of Ethiopia. An ethnobotanical survey was carried out from September 2011 to February 2012. Data were collected through semistructured interview and field and market observations. Relative frequency of citation (RFC) was calculated and preference ranking exercises were conducted to estimate the importance of the reported medicinal plants in Boricha District. A total of 42 antimalarial plants belonging to 27 families were recorded in the study area. Leaf was the dominant plant part (59.0%) used in the preparation of remedies and oral (97.4%) was the major route of administration. Ajuga integrifolia scored the highest RFC value (0.80). The results of this study revealed the existence of rich knowledge on the use of medicinal plants in the study area to treat malaria. Thus, an attempt should be made to conserve and evaluate the claimed antimalarial medicinal plants with priority given to those that scored the highest RFC values.

Evaluation of the antiplasmodial properties of selected plants in southern Ethiopia.

BACKGROUND: The majority of the Ethiopian population is at risk of malaria largely caused by Plasmodium falciparum. The resistance of the parasite to existing drugs is the main challenge in the control of the disease and thus new therapeutic drugs are required. In Ethiopia, people use different plant species to treat malaria. However, very few of them have so far been evaluated for their safety level and antimalarial activity. Thus, the aim of this study was to evaluate the safety and antimalarial activity of extracts of Ajuga integrifolia, Clerodendrum myricoides, Melia azedarach, Peponium vogelii and Premna schimperi, locally used by the Sidama people of Ethiopia to treat malaria. METHODS: The safety level of 80 % methanol extracts of the plants were evaluated using standard acute toxicity test procedure. The antiplasmodial activity of 80 % methanol extracts of the plants were assessed in vivo using Swiss albino mice against chloroquine sensitive rodent malaria parasite, Plasmodium berghei, using the standard 4-day suppressive test procedure at doses of 200,400 and 800 mg/kg/day. The 80 % methanol extract of Ajuga integrifolia that exhibited better antimalarial activity was fractionated using different solvents and screened for its phytochemical constituents and evaluated in vivo for its antimalarial activity at doses of 100, 200 and 400 mg/kg/day. RESULTS: All extracts given at the three different doses caused no lethal effect on mice in 24 h and within 10 days of observation. All extracts and fractions exhibited antimalarial activity in a dose dependant manner. The highest inhibition was exhibited by the crude extracts of A. integrifolia (35.17 %) at 800 mg/kg/day (P < 0.05). Among fractions of A. integrifolia, n-butanol fraction demonstrated the highest inhibition (29.80 %) at 400 mg/kg/day (P < 0.05). The extracts and fractions prolonged the survival time and prevented weight loss of the mice, but did not prevent PCV reduction. Phytochemical test on Ajuga integrifolia indicated the presence of alkaloids, flavonoids, saponins, terpenoids, anthraquinone, steroids, tannins, phenols and fatty acids. CONCLUSIONS: Findings show that the plants are non-toxic and demonstrate antimalarial activity in a dose dependant manner suporting claims of their traditional therapeutic value for malaria treatment. However, further in-depth investigation is required to assess the potential of the plants towards the development of new antimalarial agent.

In vivo antimalarial evaluation of some 2,3-disubstituted-4(3H)-quinazolinone derivatives.

BACKGROUND: Malaria is a neglected tropical parasitic disease affecting billons of people around the globe. Though the number of cases and deaths associated with malaria are decreasing in recent years, it is the most deadly disease in the world. This study aimed at investigating the in vivo antimalarial activities of some 2,3-disubstituted-4(3H)-quinazolinone derivatives. RESULTS: The in vivo antimalarial activities of the test compounds (6-9 and 11-13) were investigated using the 4-day suppressive standard test in mice infected with chloroquine-sensitive Plasmodium berghei ANKA strain. The tested compounds showed significant antimalarial activities with mean percentage suppression of 43.71-72.86 % which is significantly higher than the negative control group (p < 0.05). Compounds 12 and 13 displayed better antimalarial activities from the group with mean percentage suppression of 67.60 and 72.86 % respectively. CONCLUSION: The tested compounds showed significant in vivo antimalarial activities in mice infected with P. berghi ANKA strain. Thus, 3-aryl-2-(substitutedstyryl)-4(3H)-quinazolinones represent a possible scaffold for the development of antimalarial agents.

Synthesis and biological screening of some pyridine derivatives as anti-malarial agents.

Two series of pyridine derivatives were synthesised and evaluated for their in vivo anti-malarial activity against Plasmodium berghei. The anti-malarial activity was determined in vivo by applying 4-day standard suppressive test using chloroquine (CQ)-sensitive P. berghei ANKA strain-infected mice. Compounds 2a, 2g and 2h showed inhibition of the parasite multiplication by 90, 91 and 80%, respectively, at a dose level of 50 µmol/kg. Moreover, The most active compounds (2a, 2g and 2h) were tested in vitro against CQ-resistant Plasmodium falciparum RKL9 strains where compound 2g showed promising activity with IC(50) = 0.0402 µM. The compounds were non-toxic at 300 and 100 mg/kg through the oral and parenteral routes, respectively. The docking pose of the most active compounds (2a, 2g and 2h) in the active site of dihydrofolate reductase enzyme revealed several hydrogen and hydrophobic interactions that contribute to the observed anti-malarial activities.

Volatile constituents and biological activities of Pycnostachys abyssinica and Pycnostachys eminii extracts.

CONTEXT: Pycnostachys abyssinica Fresen and Pycnostachys eminii Gürke (Lamiaceae) are used in traditional Ethiopian medicine against eye and skin infections, "Mitch disease", and dysentery. OBJECTIVE: Our study was aimed at characterizing essential oil (EO), phytochemical groups, and antimicrobial and anthelmintic activity of extracts to underscore the species' indigenous medicinal use. MATERIALS AND METHODS: Plant organs of Pycnostachys species were subjected to hydrodistillation, and essential oils (EO) analyzed by GC-MS. Phytochemical compounds, antimicrobial (diffusion assay) and anthelmintic activity (bioassay) of gradient solvent extracts of different polarity were studied. RESULTS: In the stem and root EO of P. abyssinica, 25 (99%) and 30 (99.79%) compounds were detected respectively, with estragole (70.4%) (stem) and exo-fenchyl acetate (30.6%) (root) as the most abundant compounds. In leaf, stem and root EO of P. eminii, 30 (90.66%), 27 (90.59%) and 27 (99.96%) compounds were detected, respectively, with high levels of ß-caryophyllene (from 18.08% to 28.85%) and germacrene D (from 15.1% to 22.06%). Alkaloids, saponins, phytosterols, flavonoids, polyphenols, diterpenoids and carotenoids were detected in Pycnostachys. Petroleum ether, chloroform and methanol extracts showed distinct antimicrobial effects with generally higher potential activity of lipophilic and semi-lipophilic fractions. Leaf and root methanol extracts of both species showed lethal activity against earthworms. DISCUSSION: Identified EO constituents and phytochemical groups underscore the observed antifungal, antibacterial and anthelmintic activity of Pycnostachys gradient solvent extracts. CONCLUSION: EO analysis, phytochemical screening, and antimicrobial and anthelmintic assays indicate the biological potential of Pycnostachys species from Ethiopia, and emphasize their pharmacological and indigenous applications.

Constituents, antileishmanial activity and toxicity profile of volatile oil from berries of Croton macrostachyus.

The chemical composition of the volatile oil from berries of Croton macrostachyus Hochst. ex Del. was determined by GC and GC/MS. The oil was tested for its in vitro antileishmanial activity on two Leishmania strains, and its toxicity on the human monocytic leukemia (THP-1) cell line and erythrocytes from sheep blood. The main constituents of the oil were benzyl benzoate (51.8%), linalool (10.1%), gamma-muurolene (9.3%), (E,E)-alpha-farnesene (3.2%), delta-cadinene (2.8%) and alpha-curcumene (2.7%). The oil was effective against L. donovani and L. aethiopica promastigotes (MIC = 0.08 microL/mL and 0.16 microL/mL, respectively) and axenic amastigote stages (EC50 = 20.00 nL/mL and 6.66 nL/mL, respectively). The CC50 value for the oil was 10.00 nL/mL on THP-1 cells with selectivity index values of 0.5 for L. donovani and 1.5 for L. aethiopica. The median lethal concentration (LC50) of the oil was 2.45 microL/mL. Thus the observed high efficacy and moderate toxicity of the volatile oil from C. macrostachyus, makes the plant a promising source of new lead compounds in the search for safe and effective antileishmanial drugs.

Essential-oil composition, antileishmanial, and toxicity study of Artemisia abyssinica and Satureja punctata ssp. punctata from Ethiopia.

Essential oils of Artemisia abyssinica and Satureja punctata ssp. punctata from Ethiopia were analyzed by GC and GC/MS, and screened for leishmanicidal activity against promastigote and axenic amastigotes of Leishmania donovani and L. aethiopica, including toxicity studies on human monocytic leukemia cells (THP-1) and erythrocytes in vitro. GC/MS of A. abyssinica oil revealed 67 compounds (99.94%) with the major constituents yomogi alcohol (38.47%), artemisyl acetate (24.88%), and artemisia alcohol (6.70%), and oxygenated monoterpenes (84.00%) as the dominant group. The oil of S. punctata contained 67 compounds (99.49%) with the main constituents geranial (27.62%), neral (21.72%), alpha-bisabolol (13.62%), and (E)-nerolidol (4.82%), of which oxygenated mono- and sesquiterpenes (58.39 and 26.91%, resp.) showed highest abundance. Both oils showed effect on promastigotes (MIC 76.5 to 312.5 nl/ml) and amastigotes (EC(50) 4.06 to 131.00 nl/ml) of L. donovani and L. aethiopica, and varying toxicities on THP-1 cells (CC(50) 0.013 to 350 nl/ml with selectivity index between 0.001 and 28) and erythrocytes (with LC(50) 0.35 to 1.52 microl/ml). S. punctata oil exerted highest activity against both Leishmania sp. and toxicity. The revealed antileishmanial activities support further isolation and investigation of oil constituents for in vitro/in vivo evaluation.

Lead and cadmium accumulation in medicinal plants collected from environmentally different sites.

Though use of herbal medicine is increasing dramatically worldwide, environmental pollution especially with heavy metals poses serious problem on quality of medicinal plants and their products. In Ethiopia, where more than 85% of the population relies on traditional medicine, data on heavy metals level of plants is unavailable. The purpose of this study was to assess Pb and Cd in plants grown in different parts of Ethiopia. Out of 26 samples analyzed, four for lead (15.4%; 11.56 +/- 1.07 to 98.19 +/- 1.05 mg/kg) and seventeen for cadmium (65.4%; 0.38 to 1.83 +/- 0.06 mg/kg) were found to contain concentrations above WHO limits (10 mg/kg and 0.3 mg/kg respectively).