In vitro Erythrocyte Haemolysis Inhibition Properties of Senna singueana Extracts

Both leaves and bark of Senna singueana (Del.) Lock(Fabaceae) are traditionally used, in some parts of Ethiopia, for the treatment of a form of skin cancer. Also the inner bark of the plant is chewed fresh to soothe stomach spasm and smoke from the wood and bark is used as smoke baths. The objective of this work was to study the antioxidant properties, of this plant using an erythrocyte haemolysis inhibition assay, because one way to justify the traditional anticancer uses can be through the concept of antioxidant effect. Crude extracts from leaves and bark of S. singueana were prepared by maceration with 80% methanol. Fractions were prepared from both leaves and bark using solvents of different polarity (diethyl ether, chloroform, and 80% methanol). The 80% methanol fraction was partitioned using ethyl acetate. These crude extracts and solvent fractions were then evaluated for their capacity to inhibit H2O2 induced erythrocyte haemolysis. Also to evaluate the presence of any intrinsic haemolysis inducing constituents such as saponins, foaming index determination and preliminary haemolysis activity determination tests were performed on extracts from the bark and leaves of the plant. The results revealed that the ethyl acetate solvent fraction from the bark of S. singueana exhibited concentration dependent erythrocyte haemolysis inhibitory activity, with an IC50 value of 233 µg/ml. However, the other solvent fractions and crude extracts did not show meaningful haemolysis inhibitory activity. The results of the foaming index determination and preliminary haemolysis activity determination tests showed the presence of saponins; but, none of the dilutions of the extracts showed any visible haemolysis activity compared to H2O2, used as a control. The results of the ethyl acetate solvent fraction from the bark of the plant could indicate the possible presence of constituents that can inhibit erythrocyte haemolysis, which in turn, could be due to lipid peroxidation inhibitory activity.Keywords: Senna singueana, Extracts, Haemolysis Inhibition, Antioxidan

Radical Scavenging Activity and Preliminary Phytochemical Screening of Pods of Cassia arereh Del. (Fabaceae)

Cassia arereh is traditionally used as a fish poison and to manage different disease conditions including gastrointestinal tract (GIT) disorders, infertility, diabetes, insect bite, and infections. Free radicals have been implicated in the pathogenesis of a range of chronic diseases; and many medicinal plants are thought to be effective in managing such diseases, mainly through their free radicals scavenging ability. The objective of this study was to conduct phytochemical screening and investigate the free radical scavenging activity of various extracts of pods of C. arereh. Petroleum ether, ethanol, and water extracts were prepared from the pods powder and tested for their radical scavenging activity using 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) assay. The pods powder was also subjected to preliminary phytochemical screening. The results revealed that ethanol and water extracts possessed strong DPPH radical scavenging activity with 50% inhibitory concentration (IC50) values of 8.84 and 16.76μg/ml, respectively. Ascorbic acid was used as a standard and exhibited a radical scavenging IC50 value of 2.0μg/ml. Results of preliminary phytochemical screening indicated the possible presence of anthraquinones, carbohydrates, deoxy-sugars, saponins, tannins, and terpenoids. It can be concluded that pods of C. arereh may contain medicinally relevant constituents such as terpenoids and displayed strong radical scavenging activity, which may partly contribute to the possible scientific basis for its traditional use to alleviate different disease conditions.Keywords: Cassia arereh, Phytochemical screening, Radical scavenging, Traditional medicine, Ethiopia

Spatio-temporal land use/cover dynamics and its implication for sustainable land use in Wanka watershed, northwestern highlands of Ethiopia

Long-term land use and land cover (LULC) dynamics information is essential to understand the trends and make necessary land management interventions, such as in the highlands of Ethiopia. This study analyzed six decades of LULC dynamics of Wanka watershed, Northwestern Ethiopian highlands. Two sets of aerial photographs (1957 and 2017), SPOT 5 and sentinel satellite imageries were analyzed. In addition, key informant interviews, focus group discussions and field observations were used to identify the drivers and impact of LULC change. It was found that cultivated and rural settlement land (CRSL), bare land, and urban built up area have been continuously expanded at the expenses of mainly forest and shrub lands. Over the entire study period (1957–2017) while the bare land and CRSL have increased by about 59% and 20% respectively, forest and shrub lands have declined by 59% and 57% respectively. Urban built up area has also expanded. The impact of popula- tion pressure and expansion of CRSL land were considerable. The trend of LULC dynamics in the study watershed implies adverse impact on the quality and quantity of the land resource. Hence, appropriate land use planning and strategies that reduce expansion of cultivated land need to be practiced

The use of plants in the traditional management of diabetes in Nigeria: Pharmacological and toxicological considerations

Ethnopharmacological relevance: The prevalence of diabetes is on a steady increase worldwide and it is now identified as one of the main threats to human health in the 21st century. In Nigeria, the use of herbal medicine alone or alongside prescription drugs for its management is quite common. We hereby carry out a review of medicinal plants traditionally used for diabetes management in Nigeria. Based on the available evidence on the species׳ pharmacology and safety, we highlight ways in which their therapeutic potential can be properly harnessed for possible integration into the country׳s healthcare system. Materials and methods: Ethnobotanical information was obtained from a literature search of electronic databases such as Google Scholar, Pubmed and Scopus up to 2013 for publications on medicinal plants used in diabetes management, in which the place of use and/or sample collection was identified as Nigeria. ‘Diabetes’ and ‘Nigeria’ were used as keywords for the primary searches; and then ‘Plant name – accepted or synonyms’, ‘Constituents’, ‘Drug interaction’ and/or ‘Toxicity’ for the secondary searches. Results: The hypoglycemic effect of over a hundred out of the 115 plants reviewed in this paper is backed by preclinical experimental evidence, either in vivo or in vitro. One-third of the plants have been studied for their mechanism of action, while isolation of the bioactive constituent(s) has been accomplished for twenty three plants. Some plants showed specific organ toxicity, mostly nephrotoxic or hepatotoxic, with direct effects on the levels of some liver function enzymes. Twenty eight plants have been identified as in vitro modulators of P-glycoprotein and/or one or more of the cytochrome P450 enzymes, while eleven plants altered the levels of phase 2 metabolic enzymes, chiefly glutathione, with the potential to alter the pharmacokinetics of co-administered drugs. Conclusion: This review, therefore, provides a useful resource to enable a thorough assessment of the profile of plants used in diabetes management so as to ensure a more rational use. By anticipating potential toxicities or possible herb–drug interactions, significant risks which would otherwise represent a burden on the country׳s healthcare system can be avoided

In Vitro Radical Scavenging Activity of the Leaf and Bark Extracts of Senna singueana (Del). Lock

The leaves and bark of Senna singueana (Del). Lock (family: Fabaceae) are traditionally used in some parts of Ethiopia, for the treatment of a form of skin cancer locally called ‘Minshiro Nekersa\'. Total extracts and solvent fractions obtained from the leaves and bark; and fractions obtained from solid-phase extraction and TLC of the leaf extract were prepared and tested for their radical scavenging activity using DPPH (1,1- diphenyl-2-picrylhydrazyl) and deoxyribose degradation inhibition assays. The results revealed that all the samples tested possess strong DPPH radical scavenging activity and moderate deoxyribose degradation inhibitory effect. The IC50 values of the total extracts and solvent fractions ranged from 6.16 to 200.10 μg/ml in DPPH assay and 262.77 μg/ml to 1457.63 μg/ml in deoxyribose degradation inhibition assay. The TLC separated bands showed IC50 values ranging from 8.89 to 53.83 μg/ml, and 72.17 to 849.18 μg/ml, respectively, in the two assays. The positive control standard compounds ascorbic acid (for the DPPH assay) and butylhydroxytoluene (for the deoxyribose degradation inhibition assay) showed IC50 values of 4.46 and 4.76 μg/ml, respectively. As free radicals are known to be involved in carcinogenesis, radical scavengers can short-cut free radical mediated critical steps that lead into carcinogenesis. It was thus proposed that the observed radical scavenging activity of S. singueana may contribute partly to the possible scientific basis for the traditional anticancer use of the plant. Keywords: Senna singueana, Fabaceae, radical scavenging activity, DPPH assay, deoxyribose degradation inhibition assayEthiopian Pharmaceutical Journal Vol. 25 (2) 2007: pp. 77-8

In Vivo Diuretic Activity of Hydromethanolic Extract and Solvent Fractions of the Root Bark of Clerodendrum myricoides Hochst. (Lamiaceae)

Introduction. Clerodendrum myricoides (Lamiaceae) has been traditionally used for the treatment of various ailments, including body swelling and urine retention. The present study aimed to evaluate the diuretic activity of a crude extract and solvent fractions of the root bark of C. myricoides. Methodology. The coarsely powdered root bark of C. myricoides was extracted by a cold maceration method using 80% methanol. A portion of the extract was fractionated based on the polarity index of solvents to obtain chloroform, ethyl acetate, and aqueous fractions. To investigate the diuretic activity of the plant, rats were divided into fifteen groups. The normal control groups received either water or 2% tween 80, the standard group received furosemide (10 mg/kg), and the test groups were administered the hydromethanolic extract and solvent fractions at the doses of 100, 200, and 400 mg/kg by the oral route. The urine volume, urine pH, urine, and serum electrolytes were determined and compared with the standard and normal control groups. Results. The crude hydromethanolic extract, ethyl acetate, and chloroform fractions induced significant diuresis at a dose of 400 mg/kg (P<0.001) compared to the aqueous fraction. The hydromethanolic extract at 200 mg/kg and 400 mg/kg also caused noticeable diuresis (P<0.001) compared to the standard, furosemide. Rats treated with hydromethanolic extract, ethyl acetate, and chloroform fractions showed delayed onset and prolonged diuresis in a dose-dependent fashion compared to the aqueous fraction (P<0.05). The hydromethanolic extract and solvent fractions produced the highest saliuretic and natriuretic index compared to the standard, furosemide. The crude hydromethanolic extract also failed to produce any sign of toxicity up to 2000 mg/kg. Conclusion. From this study, the hydromethanolic extract and ethyl acetate fraction of the root bark of C. myricoides produced a prominent diuretic effect in rats

A Food Demand System Estimation for Rural Malawi: Estimates Using Third Integrated Household Survey Data

In contrast to the myriad of empirical work on food demand in other countries, very few studies have considered zero expenditures on some food groups. Those which have attempted have been based on techniques which result in endogeneity and inefficient estimates which in turn may misinform policy calibration. Improving on methodological flaw of previous studies, the present study censors zero expenditures in the first stage using simulation based maximum likelihood multivariate probit. In the second stage, Quadratic Almost Ideal Demand System which allows for a more realistic assumption of curvature in Engels curve is estimated. In turn, food expenditure and price elasticities are derived. In view of the high expenditure elasticities, considering a policy option that would enhance rural consumer income is desirable, since it will result in high consumption thereby providing more incentives for food production