40 research outputs found
Effect of Cymbopogon martinii, Foeniculum vulgare
This study was performed to investigate effect of essential oils on Aspergillus spore germination, growth, and mycotoxin production. In vitro antifungal and antiaflatoxigenic activities of Cymbopogon martinii, Foeniculum vulgare, and Trachyspermum ammi essential oils were carried out on toxigenic strains of Aspergillus species. Plant materials were hydrodistilled for 4-5 h in Clevenger apparatus. 0.25 μL/mL, 0.5 μL/mL, 1 μL/mL, 2 μL/mL, and 4 μL/mL concentrations of each essential oil were prepared in 0.1% Tween 80 (V/V). T. ammi oil showed highest antifungal activity. Absolute mycelial inhibition was recorded at 1 μL/mL by essential oils of T. ammi. The oil also showed complete inhibition of spore germination at a concentration of 2 μL/mL. In addition, T. ammi oil showed significant antiaflatoxigenic potency by totally inhibiting toxin production from A. niger and A. flavus at 0.5 and 0.75 μL/mL, respectively. C. martinii, F. vulgare, and T. ammi oils as antifungals were found superior over synthetic preservative. Moreover, a concentration of 5336.297 μL/kg body weight was recorded for LC50 on mice indicating the low mammalian toxicity. In conclusion, the essential oils from T. ammi can be a potential source of safe natural food preservative for food commodities contamination by Aspergillus species
Sub-chronic Toxicity of Anti-ectoparasitic Formulation Comprising Cymbopogon Citrates Essential Oil and Jatropha Curcas Fixed Oil in Swiss Albino Mice
Ectoparasites are found widely distributed in all agro-ecological zones of Ethiopia. The problems they cause can be alleviated through the use of traditional medicinal plants. Cymbopogon citratus is one of the traditional herbs commonly used for such purpose. This study was conducted to profile safety of the C. citratus based anti ectoparasitic formulation. The toxicity study had shown significant weight change in animal group that received 3.75% of the formulation. There were also significant changes in serum lipid profiles of treated group animals compared with the control. The level of uric acid in animals treated with 3.75% of the formulation showed significant increase compared with the control. Liver and kidney histopathology of both treatment group animals revealed few mononuclear leucocytic infiltrations. The blood cell parameters and different biochemical findings had revealed no sign of toxicity. However; other measured parameters like the body weight, histological and some biochemical findings had shown both significant and insignificant sign of toxicities. Therefore; it is important to consider the effect of the formulation in prolonged treatment on body weight, uric acid excretion and lipid metabolism
Khat chewing habit as a possible risk behaviour for HIV infection: a case-control study
Background: The use/abuse of psychoactive drugs such as khat leaves (Catha edulis) are believed to alter one's moods or emotional state either through the sustained release or inhibition of neurotransmitters, thereby enhancing or dampening the response of the individual. Most people whose thinking are warped by continued drug use may not be able to see the harm resulting from their actions. Thus, there has been a strong linkage between drug use and casual or unsafe sexual practice despite the serious concern about HIV infection. Objective: Khat chewing is known to be a widespread habit in Ethiopia. This study is, thus, aimed at investigating whether or not the use of this psychostimulant alone or in conjunction with other behaviors associated with its use constitutes a risk behavior that accelerates the spread of HIV infection. Methods: A case-control study involving 850 human subjects, i.e. 425 HIV positives (cases) and 425 HIV negatives (controls) was conducted using rapid test algorithm and/or western blot method for determination of HIV status. Both groups were interviewed about their probable khat chewing habits, alcohol intake, multiple sexual practice, and the like, using a structured questionnaire. The data were analysed using SPSS/PC + statistical software.Results: Risk behaviors for HIV infection such as khat chewing in conjunction with alcohol intake and casual sex were observed more in people with HIV than in the control group. Khat chewing was significantly associated with multiple sexual practice (OR = 4.03, 95% CI = 3.02, 5.39), which in turn was strongly linked with HIV cases (OR = 3.52, 95% CI = 2.64, 4.69). Thus, more than the non-chewers, khat chewers constituted significantly higher number of HIV cases (OR =2.32, 95% CI = 1.75, 3.07).Conclusion/Recommendations: Khat chewing is a risk behavior for the spread of HIV infection. Mainstreaming of khat control into national development planning initiatives is recommended.The Ethiopian Journal of Health Development Vol. 19(3) 2005: 174-18
Anti-bacterial activity of Plumbago zeylanica L. roots on some pneumonia causing pathogens
The anti bacterial activity of polar and non-polar extracts prepared from the roots of Plumbago zeylanica L. (Plumbaginaceae), a plant widely used in Ethiopian traditional medicine for various ailments were investigated using hole plate diffusion method against some pneumonia causing pathogens. The aqueous extract did not exhibit any activity while petroleum ether extract was found to have strong anti-bacterial effects as compared to the ethanol extract which showed a significant activity. Activity guided chromatographic purification of the petroleum ether extract led to the isolation of three compounds, of which the compound identified as 5-hydroxy-2-methyl-1, 4-naphthoquinone, plumbagin, found to be the active component on the tested microorganisms. Minimum inhibitory concentration value of this particular compound showed comparative activity resembling the commonly used broad spectrum antibiotic, tetracycline. The strong antibacterial effect of the petroleum ether extract is discussed to show that it was attributable to this compound rather than the other two that were found to have trace of activities.
Key words/phrases: Anti-bacterial activity, Minimum inhibitory concentration, Plumbago zeylanica, pneumonia
SINET: Ethiopian Journal of Science Vol.25(2) 2002: 285-29
QUANTITATIVE DETERMINATION AND OPTIMIZATION OF EXTRACTION CONDITIONS FOR EMBELIN IN EMBELIA SCHIMPERI BY UV-VIS SPECTROMETRY
Embelin is a unique chemical compound found in nature, composed of quinone moiety resembling Coq10 (Ubiquinones), having ketone and hydroxy groups with an aliphatic chain. An Optimum solvent for extracting Embelin from Embelia schimperi and its simultaneous determination of the content of Embelin in the extract has been performed using UV-VIS spectrometry. The identification of Embelin spot obtained from hot ethyl acetate extract of the seed is confirmed by Nuclear Magnetic Spectroscopy (NMR). A plot of peak absorbance versus concentration of Embelin was found to be linear over the range of 3-12 μg/ml. The limit of detection was 0.11μg/ml and the limit of quantitation was 0.37 μg/ml. Extraction conditions were also optimized for the best possible extraction of Embelin from the fruits of Embelia schimperi in different solvent polarity like n-hexane, carbon tetrachloride, diethyl ether, chloroform, ethyl acetate, propanol and ethanol. The determination of Embelin in various solvent extract exhibited a mean content of 0.66-5.79 % w/w. Carbon tetrachloride and ethyl acetate was found to be best for the highest possible recovery of the analyte, Embelin. The developed UV method was validated in terms of precision, accuracy, stability, LOD and LOQ Keywords: Embelia schimperi, Embelin, spectrometry, extractio
The Effect of Cymbopogon citratus Essential Oil-Water Emulsion on Some Blood Parameters and Histopathology of Liver and Kidney in Mice
This study was aimed to assess the possible toxic effects o
Effect of Ultrasound-Assisted Extraction of Moringa stenopetala Leaves on Bioactive Compounds and Their Antioxidant Activity
Moringa stenopetala je višenamjenska biljka s izraženim nutritivnim i terapeutskim svojstvima. Svrha je ovoga rada bila ispitati utjecaj vremena i temperature ekstrakcije potpomognute ultrazvukom na izdvajanje bioaktivnih spojeve i antioksidacijsku aktivnost ekstrakta lista biljke M. stenopetala. Ekstrakcija je provedena pri temperaturama od 30, 40 i 50 °C tijekom 10, 20 i 30 minuta. Ispitan je i međusobni utjecaj vremena i temperature ekstrakcije na ukupne udjele fenola i flavonoida, antioksidacijsku aktivnost (mjerenu pomoću ABTS, DPPH i FRAP metoda) i sposobnost keliranja Fe2+ iona. Nakon 20 min ekstrakcije pri 40 °C dobiven je najveći udjel ukupnih fenola u suhoj tvari, izražen kao ekvivalent galne kiseline, i to 46,6 mg/g, te najveći udjel ukupnih flavonoida u suhoj tvari, izražen kao ekvivalent katehina, i to 20,4 mg/g. Pri istim je uvjetima izmjerena najveća antioksidacijska aktivnost ekstrakata, izražena kao ekvivalent Troloxa u suhoj tvari, i to 336,5 mg/g prema DPPH metodi, 581 ,8 mg/g prema ABTS metodi i 1 33,3 mg/g prema FRAP metodi. Sposobnost keliranja, izražena u ekvivalentima EDTA u suhoj tvari, bila je 28,4 mg/g. Najmanje bioaktivnih spojeva i najmanja antioksidacijska aktivnost opaženi su u ekstraktima dobivenim nakon 30 min pri 50 °C, te nakon toga u ekstraktima dobivenim pri nižoj temperaturi (30 °C) i kraćem vremenu trajanja (10 min). Morfološka je analiza ostataka dobivenih nakon ekstrakcije pomoću pretražnog elektronskog mikroskopa pokazala veća oštećenja strukture uzorka pri duljem vremenu ekstrakcije. Stoga je zaključeno da su temperatura od 40 °C i vrijeme ekstrakcije od 20 min optimalni za izdvajanje bioaktivnih spojeva iz lišća biljke M. stenopetala.Moringa stenopetala is a multipurpose plant having high nutritional and medicinal values. The aim of this study is to evaluate the effect of time and temperature of ultrasound-assisted extraction on bioactive compounds and antioxidant activities of M. stenopetala leaf extract. The ultrasound-assisted extraction took place at each of 30, 40 and 50 °C for 10, 20 and 30 min. The study also included the analysis of the interaction effects of time and temperature on the total phenolic content, total flavonoid content, antioxidant activity (ABTS and DPPH assay), FRAP and chelating activity. The highest total phenolic content, expressed in mg gallic acid equivalents per g dry mass, was 46.6 and total flavonoid content, expressed in mg catechin equivalents per g dry mass, was 20.4 at 40 °C for 20 min. Under the same conditions, the highest antioxidant activities evaluated by DPPH, ABTS and FRAP, expressed in mg Trolox equivalents per g dry mass, were 336.5, 581.8 and 133.3 respectively, and chelating activity, expressed in mg EDTA equivalents per g dry mass, was 28.4. The lowest amounts of bioactive compounds and antioxidant activities were observable when the extraction occurred at 50 °C for 30 min, followed by the extraction at lower temperature (30 °C) for shorter time (10 min). The morphological analysis of the residues obtained after extraction using scanning electron microscope indicated that there was a higher ultrasonic destruction of the structural components of the sample at longer extraction time. Therefore, ultrasound-assisted extraction at a temperature of 40 °C for 20 min is the best time-temperature combination to extract bioactive compounds from M. stenopetala leaves
Zingiber Officinale Roscoe and Echinops Kebericho Mesfin Showed Antiplasmodial Activities against Plasmodium Berghei in a Dosedependent Manner in Ethiopia
BACKGROUND: The emergence and spread of Plasmodium falciparum resistance to antimalarial drugs necessitated the search for new drugs from natural products. Zingiber officinal Roscoe and Echinops Kebericho Mesfin are traditional herbal medicines widely used for the treatment of malaria in Ethiopia. The aim of the study was to assess the toxicity profile and in vivo antiplasmodial activities of 70% methanol crude extracts of both plant materials against Plasmodium berghei.METHODS: Healthy male Swiss Albino mice of age 4-5 weeks and weight 25-36 g were infected by P. berghei. The extracts were administered orally at doses 5000, 2500 and 1250 mg/kg for acute toxicity of E. kebericho Mesfin. Graded doses at 1000, 500 and 250 mg/kg used for four days suppressive studies. Parasitemia, body weight, packed cell volume (PCV) and survival time were determined. SPSS Version 20 was used for the analysis of data of parasitemia, body weight, PCV, and survival times. Statistical significance was determined by one-way ANOVA. Independent ttest was used to compare results. Results were presented as a mean ± standard error of the mean (M ± SEM). All data were analyzed at a 95% confidence interval (α= 0.05).RESULTS: At the dose of 5000 mg/kg, E. kebericho Mesfin showed no toxic effects. The LD50 of extract could go beyond the dose used. In vivo antiplasmodial activity of extracts showed excellent chemo suppression at 500 and 1000 mg/kg in a dose dependent manner compared with the negative control. The chemo suppressions of the 1000 mg/kg of both plant extracts were 49.53 ± 1.90% and 32.83 ± 1.03%, respectively. The survival times of P. berghei infected mice were also a dose dependent manner while failed to prevent weight loss.CONCLUSION: The extracts of both medicinal plants showed antiplasmodial activities against P. berghei. It confirmed the literature findings and their traditional uses.
Insecticidal Activity of Some Traditionally Used Ethiopian Medicinal Plants against Sheep Ked Melophagus ovinus
Twelve medicinal plants and a commercially used drug Ivermectin were examined for insecticidal activity against Melophagus ovinus sheep ked at different time intervals using in vitro adult immersion test. The findings show that at 3.13 µL/mL, 6.25 µL/mL and 12.5 µL/mL concentration of Cymbopogon citratus, Foeniculum vulgare and Eucalyptus globulus essential oils respectively, recorded 100% mortalities against M. ovinus within 3 hour of exposure. Significantly higher insecticidal activity of essential oils was recorded (P=0.00) when compared to 10 μg/mL Ivermectin after 3-hour exposure of M. ovinus at a concentration of ≥1.57 μL/mL, ≥3 μL/mL, and ≥12.7 μL/mL essential oils of C. citratus, F. vulgare, and E. globulus, respectively. Among essential oils, C. citratus has showed superior potency at a three-hour exposure of the parasite (P=0.00) at a concentration of ≥0.78 μL/mL. Strong antiparasitic activity was recorded by aqueous extract of Calpurnia aurea (80% mortality) at a concentration of 200 mg/mL within 24 h among aqueous extracts of 9 medicinal plants. The results indicated all the four medicinal plants, particularly those tested essential oils, can be considered as potential candidates for biocontrol of M. ovinus sheep ked
Comparative analysis of lamivudine in two commercially available brands using HPLC and UV-VIS spectroscopy
One of the components of care for people living with HIV/AIDS is the use of antiretroviral drugs (ART) and the successful outcome of these drugs requires proven quality, safety and efficacy. The quality of these drugs can be assessed by qualitative and quantitative analysis using different analytical techniques. The objective of this study is to compare the analytical results of two brands of ART drug, Lamivox-150 and Lamidine using high pressure liquid chromatography (HPLC) and UV spectroscopy in order to select a validated, simple, cost-effective and affordable analytical technique. The two brands of a lamivudine tablets were quantified against a reference standard, lamivudine with HPLC and UV spectroscopy and the results were compared. The HPLC method involves the use of methanol:acetonitrile (5:95) as a mobile phase, and octadecylsilane (C18) as a stationary phase. For UV spectroscopic analysis, complete release of the active ingredient from the tablets was achieved with 0.01N HCl using ultrasonic bath for 10 min. This is followed by subsequent quantitative determination of the released drug at maximum absorbance wavelength of 280 nm. Concentrations of lamivudine ranging from 0.2-2 mg/ml and 1.6-16 µg/m were used to construct calibration curves for HPLC and UV spectroscopic analyses, respectively. The content of lamivudine per tablet in Lamivox-150 and Lamidine was found to be in agreement with the labelled amount when analysed by both techniques (