Ethiopian Pharmaceutical Journal

Toxic Effects of 70% Ethanol Moringa stenopetala (Baker f.) Cufod. (Moringaceae) Leaf Extract on Wistar Albino Rat Embryos

Hussen Abdu — 2023-08-18

Moringa stenopetala (Baker f.) Cufod. (Moringaceae) is a fast-growing tropical plant used as a native vegetable in southwestern Ethiopia. The plant is used for treating different diseases like malaria, hypertension, stomach pain, diabetes, and retained placenta. Yet, evidence of its teratogenicity is limited. The current study aimed to assess the toxic effects of M. stenopetala leaf on rat embryos. The leaves of M. stenopetala were extracted using 70% ethanol. Five groups of animals, each containing ten pregnant rats, were used for the current study. The first three groups were treated with 250, 500, and 1000 mg/kg M. stenopetala leaf extract, respectively. The last two groups were pair-fed and ad libitum control groups. The extract was administered from gestation days 6 to 12. Embryos were recovered at day 12 of gestation and assessed for growth retardations and development delays. When compared with the pair-fed control group, the maternal daily food intake and weight gain were slightly reduced in the high (1000 mg/kg) treated group, but it was not statistically significant. Increased numbers of resorption sites were observed in the 1000 mg/kg treated group when compared with the pair-fed control group. The number of embryos was also significantly reduced in the high dose treated group. The crown-rump length, number of somites, yolk sac diameter, and morphological scores of the embryos were also significantly reduced in 1000 mg/kg treated rats when compared with the pair-fed control group. When compared to pair-fed control group, the high dose treated rats had developmental delays in the yok sac circulation, otic system, and somite score. Therefore, administration of M. stenopetala leaves at a higher dose was found to have toxic effects on the development of rat embryos. It increased resorption sites and reduced the number of embryos at a higher dose. In addition, it delayed the development of yolk sac circulation, sensory otic system, and somite scores in the high dose treated rat embryos. Hence, it is recommended to limit excess consumption of M. stenopetala leaves during pregnancy.

Anti-Inflammatory Activity of 80% Methanol Leaf Extract of Urtica simensis Steudel (Urticacaeae) in Rodents

Getu Dadi — 2023-08-18

The leaves of Urtica simensis Steudel (Urticacaeae) have long been used traditionally to cure a variety of diseases, including eye injuries, gonorrhea, erectile dysfunction, malaria and peptic ulcer disease. They are also claimed to have anti-inflammatory and wound-healing properties. However, there is no scientific evidence to back-up the traditional assertions. The aim of this study was to evaluate in vivo anti-inflammatory activity and to quantitatively determine the major chemical constituents of the 80% methanol leaf extract of U. simensis. The anti-inflammatory activity was evaluated at doses of 100, 200 and 400 mg/kg of the leaf extract using acute model of inflammation (carrageenan induced hind paw oedema) and chronic model of inflammation (cotton pellet induced granuloma) in rats. U. simensis leaf extract had a statistically significant effect on the carrageenan-induced paw oedema and cotton pellet-induced granuloma models. The 400 mg/kg dose demonstrated maximum percent of inhibition of oedema i.e. 27.61% and 35.42%; p < 0.001 at 3rd and 4th h of post-induction, respectively, which is comparable to indomethacin. All the tested doses showed significant (p < 0.001) exudate and granuloma inhibition in cotton pellet induced granuloma model. Phytochemical analysis revealed total values of 26.70 ± 0.14 mg GAE/g of dry weight of extract for phenolic compounds, 13 ± 0.18 mg QE/g of dry weight of extract for flavonoids, and 17.06 ± 0.11 mg AE/g of dry weight of extract for alkaloids in the 80% methanolic leaf extract of U. simensis. Data obtained from the present study generally justified that the 80% methanol leaf extract of U. simensis had significant anti-inflammatory activities, supporting the folkloric use of the plant.

Synthesis and Characterization of Cellulose Acetate from Khat (Catha edulis) Waste

Kebede Wondu — 2023-08-18

Agro-industries produce a lot of lignocellulosic waste, and using this cellulose-rich waste can help with both ecological and economic issues. In this study, cellulose fibers were isolated from a locally abundant source of khat waste and homogeneously acetylated to produce cellulose acetate. In order to determine their yield, chemical functionality, crystallinity, shape, and thermal stability, the as-obtained cellulose fibers and cellulose acetate were analyzed. Cellulose content on a dry weight basis was found to be about 40% in untreated khat waste and about 90% in as-obtained cellulose fibers. The degree of substitution of cellulose acetate ranged from 1.4 to 2.1 with weight gains from 133 to 146% (w/w). SEM images indicated that the asobtained cellulose existed as a fibrous and elongated structure while the cellulose acetate was granular. The FTIR results showed the removal of non-cellulosic materials during chemical treatments of khat waste. Furthermore, an effective attachment of acetate groups was confirmed by the appearance of new peaks around 1743 cm-1, 1368 cm-1, and 1221 cm-1 in the FTIR spectra of cellulose acetate. The elimination of noncellulosic components, notably hemicellulose and lignin, was demonstrated by an increase in the crystallinity index (CrI) of extracted cellulose (73%) after chemical treatment of untreated khat waste (56%). This index then reduced in the cellulose acetate following esterification. This study is beneficial for developing cellulose and cellulose acetate from khat waste as an alternative source for various potential value-added applications.

Chemical Composition and In Vitro Antimicrobial Activity of the Essential Oil of the Roots of Silene macrosolen

Gizachew Kassahun Bizuneh — 2023-08-18

Medicinal plants have always played a crucial role as sources for drug lead compounds. Thus, the objective of this study was to qualitatively identify and quantitatively determine the chemical compositions of the essential oil extracted from the roots of Silene macrosolen Steud. ex A. Rich (Caryophyllaceae) and also to quantitatively assay the antimicrobial efficacy of the essential oil against selected medicinally important pathogenic microorganisms. The essential oil was extracted from the root of S. macrosolen by hydrodistillation using Clevenger-type apparatus and analyzed for its chemical compositions by capillary gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of the oil was evaluated on ten bacterial and three fungal species using the microdilution technique. GC-MS analysis of the essential oil resulted in the identification of 44 compounds that account for 64.63% of the total oil content. The major constituents of the oil were hydrocarbons that include 3,7-dimethyldecane (11.29%), tridecane (9.42%), 4-ethyltetradecane (6.92%), pentadecane (4.90%), and 7-methyl-1-undecene (4.62%). Overall, the oil showed higher antibacterial activities against Gram-positive than Gram-negative bacteria. In particular, the oil exhibited strong activity against Staphylococcus aureus and Staphylococcus epidermidis with an MIC value of 31.5 μg/ml. The results indicate that the essential oil of S. macrosolen roots contains mainly long-chain hydrocarbons which may be responsible for the antimicrobial activity of the plant.

Distilled Lupinus albus Seeds Induce Vasorelaxation by Activation of eNOS-NO-cGMP Pathway and Direct Inhibition of Voltage Dependent Calcium Channels

Yoseph Likey — 2023-08-18

Hypertension is a global health problem that needs exploration for new therapeutics. The community in North Western Ethiopia uses a local alcoholic beverage prepared from Lupinus albus L. seeds for the treatment of hypertension. Although this preparation has been traditionally used as an antihypertensive preparation, it lacks scientific evidence regarding efficacy and possible mechanisms of its antihypertensive action. The aim of this study was to investigate the ex vivo vasorelaxation activity and possible mechanisms of L. albus seed distillate (“gebto arekei”) in isolated guinea pig thoracic aorta. The vasorelaxation effect of different concentrations of the distillate (4 - 32 μg/ml) was investigated in isolated thoracic aorta strips pre-contracted by either epinephrine (1 μM) or potassium chloride (80 mM) using ex vivo isometric tension recording method. The extract induced vasorelaxation response in both endothelium intact and endothelium denuded strips as well as strips pre-incubated with NG-nitro-L-arginine methyl ester (L-NAME) and methylene blue (MB) in concentration-dependent manner. The distillate showed synergistic activity when combined with sodium nitroprusside. Determination of calcium concentration responses revealed significant inhibition of contraction. The concentration that caused maximal relaxation and 50% maximal relaxation was found to be 4.74 μg/ml and 3.80 μg/ml, respectively, in epinephrine pre-contracted endothelium intact strips, whereas it was 21 μg/ml and 7.01 μg/ml in strips pre-contracted with potassium chloride. Distilled L. albus seeds showed vasodilatory effect through endothelial nitric oxide synthase-nitric oxide-cyclic guanosine monophosphate pathway and direct inhibitory effect on voltage dependent calcium channels that supports its traditional use in the treatment of hypertension.

In Vitro Antiprotozoal Activity of the Leaf Latex of Caralluma speciosa Against Two Leishmania Species

Alemu Tadesse Feroche — 2023-08-18

The alarming growth of parasite resistance has increased the urgency of finding novel therapeutic compounds for the treatment of protozoal diseases such as leishmaniasis. Previous studies have demonstrated that several plants belonging to the genus Caralluma possess antiprotozoal activity against malaria, trypanosomiasis and leishmaniasis. In the present study, the antiprotozoal activity of the methanolic extract of the leaf latex obtained from the Ethiopian plant Caralluma speciosa N. E. Br. (family Asclepiadaceae) was evaluated by in vitro testing against Leishmania aethiopica and L. donovani. Antileishmanial activity test was carried out using the Alamar Blue assay on promastigotes and axenic cultured amastigotes of L. aethiopica and L. donovani clinical isolates, and cell viability was fluorometrically determined. Amphotericin B was used as a positive control, and 1% dimethyl sulfoxide (DMSO) and the media were employed as a negative control. Results of the study indicated that the latex possessed good activity against both parasites with IC50 values of 18.32 ± 0.85 and 26.21 ± 0.90 μg/ml against promastigotes, and 25.72 ± 0.76 and 25.33 ± 0.65 μg/ml against axenically cultured amastigotes of L. aethiopica and L. donovani, respectively. Furthermore, the latex showed selectivity indices (SIs) of 7.88 and 5.51 toward promastigotes and 5.61 and 5.70 toward amastigotes, while amphotericin B demonstrated SIs of 10.32 and 10.55 toward promastigotes and 9.76 and 10.10 toward amastigotes of L. aethiopica and L. donovani, respectively. The findings of this investigation attest that the latex of C. speciosa is endowed with promising antileishmanial activity against and L. aethiopica and L. donovani warranting further investigations into the active constituents.