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BACKGROUND: Calpurnia aurea (Ait.) Benth. leaves are used to treat different diseases like ectoparasite infestation, diarrhea, sores, anthrax, fevers, pain, and snake venom. The leaves of Calpurnia aurea were first extracted by methanol and further fractionated with the help of n-hexane, dichloromethane and ethyl acetate with increasing polarity. METHODS: The antibacterial activities of the fractions were evaluated against disease causing bacteria using agar well diffusion. The minimum inhibitory concentrations (MIC) of the fractions were determined by the micro-broth dilution method using tetrazolium salt colorimetric assay. The antioxidant activities of the solvent fractions were determined by phospho-molbedum reduction assay, reducing power assay and hydroxyl radical scavenging activity. RESULTS: The average MIC value of C. aurea fractions ranged from 1.95mg/mL to 31.25mg/mL, 7.81mg/mL to 31.25mg/mL and 13.02mg/mL to 62.5mg/mL, for ethyl acetate, dichloromethane and n-hexane fractions, respectively. The leaf extracts have a higher antioxidant effect, as shown in the phospho-molbedum reduction assay, reducing power and hydroxyl radical scavenging assay. CONCLUSION: The ethyl acetate and dichloromethane fractions revealed significant antibacterial effects against the growth of pathogenic bacteria. However, the n-hexane fraction showed the least antibacterial effect against all of the test bacteria. Furthermore, the n-hexane fractions of C. aurea showed higher antioxidant activity.
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INTRODUCTION: The present trial aimed to investigate invitro anthelminthic activities of selected tropical tanniferous plant extract on egg hatchability and larval development inhibition of Haemonchus contortus in sheep. In view of that, three tropical tanniferous plants Rhus glutinosa, Syzygium guineensa and Albizia gumifera, were selected based on their relative high content of condensed tannins. METHODS: In this study, eggs were collected from artificially infected with H. contortus. Then the egg was directly subjected to invitro assay with these condensed tannin-enriched extracts using egg hatchability assay and inhibition of larval development assay. RESULTS: The result showed that extracts from all three tropical tanniferous plants demonstrated statistically significant (P < 0.05) dosedependent inhibition of both egg hatchability and larval development. According to IC50 and IC90 values, the condensed tannin-enriched extracts inhibiting egg hatching and larval development most potently were Rhus glutinosa followed in descending order of activity by Syzygium guineensa and Albizia gumifera. DISCUSSION: The result of this study showed that these condensed tanninenriched extracts were effective in inhibiting egg hatchability as well as larval development. Therefore, condensed tannin might be recommended as one of the options for the control of H. contortus in sheep.
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The current study was undertaken from December 2015 to May 2016 with the aim of determining and comparing the pathogenicity and response to diminazene aceturate (DA) and isometamidium chloride (ISM) treatment in experimentally infected mice with trypanosome isolates from Jawi and Birsheleko areas of northwest Ethiopia. A total of 42 mice were used for the experiment. These mice were randomly assigned in to 7 groups of 6 mice per group. Three of the groups (Group 1, 4 and 5) were inoculated with trypanosome isolated from Jawi and three other groups (Group-2, 6 and 7) were inoculated with trypanosome isolated from Birsheleko and the remaining one group (Group 3) was negative control. Each experimental mice were received 0.3 ml of positive blood at the 105 parasites/ml from donor animals intraperitoneally while negative control group were received 0.3 ml sterile water. The mice were clinically observed daily during the study period. Parameters including level of parasitaemia, body weight, PCV and hemoglobin value were recorded once per week for ten consecutive weeks post infection. Trypanocidal treatment was given on day 21 post infection when peak parasitaemia was detected in groups (Group 4-DA-Jawi, 5-ISM-Jawi, 6-DA-BRSH and 7-ISM-BRSH). The treatment doses for DA was at 28 mg/kg and for ISM at 4 mg/kg. In all experimental groups during study period when the mice showed severe clinical signs and at the end of the experiment they were euthanized with 70% ethanol for gross and histopathological examinations. The parameters measured during the study period revealed markers leading to pathological changes in all infected groups. Parasitaemia were detected early in the Jawi isolate infected groups compared to the Birsheleko groups. All infected mice showed clear clinical manifestation of depression, weight loss, reduction in feed intake and huddled together in the corner of the cage. Significant (P < 0.05) reduction was observed in the mean PCV and hemoglobin value of s infected mice compared to the negative control. The mean PCV values of Birsheleko isolate infected group was significantly (P < 0.05) lower than Jawi isolate infected group. This study showed that treatment with either DA or ISM were unable to clear parasitaemia indicating the presence of drug resistance problems for both isolates. Relative improvement in clinical and pathological changes was observed as compared with untreated infected groups. Gross and histopathological lesions were observed in infected groups. In conclusion, the current study suggests the presence of strain difference in virulence between isolates and the drugs unable to cure infections indicating the presence of resistance problems necessitate further molecular characterization of the strains and drug resistance detection in the natural host.
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Infectious diseases are the critical problems of the world as a result of the emergence of different antimicrobial resistant microorganisms due to several reasons like misuses and repeating uses of antibiotics. Because of this, searching of new treatment method is important from natural substances to against those infectious diseases in both human and animals' aspects. Among those plants, Sida rhombifolia has various roles against those infectious diseases through its different phytochemical components. The objectives of this study were assessing the antibacterial activity of the aqueous-methanol extract of the plant's aerial part and knowing the phytochemical constituents of the plant. Preliminary phytochemical screening revealed that the extract of S. rhombifolia's aerial part possesses flavonoids, alkaloids, polyphenols, and quinines. In addition to this, the antibacterial activity of the plant extract was evaluated on five pathogenic bacteria species using agar well diffusion method at different concentrations of plant extracts. Minimum inhibition concentration and minimum bactericidal concentration determinations were done by tetrazolium chloride microtiter dilution assay. The inhibition zone of mean diameters ranging from 0.00 to 7.67mm against all test bacteria was significantly (p<0.05) much less than that of the positive control Chloroamphinicole (30µg/disc) with the range of 14.33mm-15mm of inhibition zone of diameters. The inhibition zones of the tested bacteria at the concentration of 62.5mg/ml were much less than the higher concentration (500mg/ml) and significantly different (p<0.05), whereas the MIC value ranges from 4.62 to 97.22mg/ml and the MBC value ranges from 4.62 to 125.00mg/ml. Even if the plant extract showed antibacterial activity, it was lower than that of other solvent extraction methods; so other solvent extraction methods and fractionates must be conducted to investigate the antibacterial activities of the plant extract on different bacterial strains and species that cause different diseases.
