Antimicrobial Potency of Methanolic Leaf Extracts from Selected Medicinal Plants against Staphylococcus aureus

2016 ◽  
Vol 05 (01) ◽  
Author(s):  
Rachuonyo HO ◽  
Ogola PE
2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Johana Rondevaldova ◽  
Olga Leuner ◽  
Alemtshay Teka ◽  
Ermias Lulekal ◽  
Jaroslav Havlik ◽  
...  

Bacterial infections are in less-developed countries traditionally treated by remedies prepared from medicinal plants.Embelia schimperi(Vatke) is a plant used as a taenicide or disinfectant in Ethiopia, very often taken mixed with another plant species. In the present study, we examined two extracts prepared from seeds and twigs with leaves ofE. schimperiand its main present secondary metabolite embelin for their antibacterial combinatory effect with oxacillin and tetracycline against sensitive and resistantStaphylococcus aureusstrains. Minimum inhibitory concentrations were determined through the broth microdilution method, whereas the combinatory effect was evaluated through fractional inhibitory concentration sum (ΣFIC) indices. Results show many positive interactions and synergy occurring in embelin and oxacillin combinations against 4 out of 9 strains (ΣFIC 0.203–0.477) and for embelin and tetracycline combination against 3 out of 9 strains (ΣFIC 0.400–0.496). Moreover, the resistance to oxacillin has been overcome in 2 strains and to tetracycline in 3 strains. According to our knowledge, this is the first study showing antimicrobial combinatory effect ofE. schimperias well as of embelin. These findings can be used for the further research targeted on the development of new antistaphylococcal agents.


Author(s):  
Vijayalakshmi N ◽  
Mudiganti Ram Krishna Rao

Objective: The present study deals with the antioxidant assays of the different leaf extracts of two medicinal plants, Sphaeranthus indicus and Psophocarpus tetragonolobus. Methods: Dried leaves of S. indicus and P. tetragonolobus were packed in separate round bottom flasks for sample extraction using ethanol, methanol, hexane, and distilled water as solvents for 72 h, and the extracts were collected after evaporating the solvents. Antioxidant studies of the various extracts were performed by 1-diphenyl-2-picrylhydrazyl and Ferric Reducing Ability of Plasma assays.Results: Among the two plants studied, S. indicus showed better 2-diphenyl-1-picryl-hydrazyl (DPPH), scavenging activity than P. tetragonolobus with IC50 values of 174.380 and 262.313, respectively, as compared to that of the standard, ascorbic acid, IC50 value of which being 111.16. The FRAP assay results for both the plants indicated that the methanol fractions showed closer results when compared with standards, ascorbic acid and quercetin. The IC50 value of S. indicus, P tetragonolobus, ascorbic acid, and quercetin was 70.065, 151.953, 85.162, and 79.647, respectively. These results clearly indicate that S. indicus methanol fraction had better antioxidant activity when compared to both standards.Conclusion: It is concluded that S. indicus and P. tetragonolobus have excellent antioxidant activities which could be the major contributing factors for their medicinal roles. Further studies in this direction are being carried on.


2020 ◽  
Vol 26 (6) ◽  
pp. 200454-0
Author(s):  
Sabaoon Shamshad ◽  
Jamshaid Rashid ◽  
Ihsan-ul-haq ◽  
Naseem Iqbal ◽  
Saif Ullah Awan

Multidrug resistance of bacteria is an emerging human health hazard and warrants development of novel antibacterial agents with more effective mode of action. Here, zinc oxide and silver nanomaterials were prepared using Ficus palmata Forssk leaf extract with efficient antibacterial activity. SEM coupled with EDS confirmed the spherical symmetry with average particle diameter 50 to 65 nm while the XRD confirmed crystalline face centered cubic structure of silver and hexagonal crystallize phase of zinc oxide nanoparticles. Antibacterial activity was evaluated for 8 pathogenic bacterial strains including 3 drug resistant pathogenic strains. The nanoparticles showed enhanced growth inhibition for resistant strains in comparison with the broad-spectrum antibiotics i.e. roxithromycin and cefixime. Minimum inhibitory concentration in μg.mL<sup>-1</sup> of silver nanoparticles was found to be as low as 33.3 for resistant Streptococcus haemolyticus; 11.1 for Staphylococcus aureus and E Coli; and 3.7 μg.mL<sup>-1</sup> for resistant Pseudomonas aeruginosa. Similarly, the minimum inhibitory concentration of zinc oxide nanoparticles was found to be 100 μg.mL<sup>-1</sup> against resistant Streptococcus haemolyticus and Staphylococcus aureus; 11.1 μg.mL<sup>-1</sup> for resistant Pseudomonas aeruginosa; and 3.7 μg.mL<sup>-1</sup> against resistant E coli. Ficus palmata Forssk leaf extracts can be explored effectively for synthesizing active antibacterial nanomaterials as a non-toxic and environmentally benign synthesis route.


2019 ◽  
Vol 5 (2) ◽  
pp. 117-137 ◽  
Author(s):  
Maureen U. Okwu ◽  
◽  
Mitsan Olley ◽  
Augustine O. Akpoka ◽  
Osazee E. Izevbuwa ◽  
...  

2006 ◽  
Vol 1 (10) ◽  
pp. 1934578X0600101 ◽  
Author(s):  
Surya Hadi ◽  
John B. Bremner

A new, weakly antibacterial indole alkaloid, named lombine, together with the known alkaloid voacangine, have been isolated from the bark of Voacanga foetida (Bl.) Rolfe (Apocynaceae), a plant used on Lombok, Indonesia, for medicinal purposes. A combined chemo- and bio-rational strategy was developed to target this plant for investigation. Lombine was shown to be bactericidal against Staphylococcus aureus and Escherichia coli.


2020 ◽  
Vol 2020 ◽  
pp. 1-6 ◽  
Author(s):  
Desta Berhe Sbhatu ◽  
Haftom Baraki Abraha

Medicinal plants and plant remedies have been in use in Ethiopia for centuries. Studies on ethnobotany, ethnomedicine, and ethnoveterinary estimate that nearly 80% of Ethiopians use some type of medicinal plants and plant remedies. Medicinal plants are regarded as the most important and sometimes the only source of therapeutics in the country. Some 800 plant species are used as sources of medicine to treat about 300 physical and mental disorders. However, because these plant species are not adequately studied, there is a big limitation in their documentation, profiling, and management. Moreover, there is a continuous loss of knowledge about medicinal plants because the communities and people are adopting new lifestyles. Hence, this article reports the finding of a study aimed at providing the gross phytochemical characteristics and antimicrobial activities of ethanol and aqueous extracts of fruit, leaf, and stem of Solanum incanum L. against two Gram-negative (Escherichia coli and Salmonella typhi) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacteria for developing gross antimicrobial profile of the plant. Phytochemical screening of fruit, leaf, and stem extracts of S. incanum has shown that it is the source of alkaloids, saponins, flavonoids, glycosides, terpenoids, and steroids. According to agar disc-diffusion tests, 100 mg/mL extracts of the plant produced bacterial growth inhibition zones of 0.00 to 16.06 mm. Ethanol and aqueous leaf extracts produced inhibition zones ranging from 11.34 to 16.06 mm against all bacterial species. The greatest inhibition zone of 16.06 mm was recorded in E. coli subjected to ethanol leaf extract. The same extract resulted in a growth inhibition zone of 16.04 mm in S. aureus. The greatest growth inhibition zones in B. subtilis (13.34 mm) and S. typhi (11.56 mm) were observed with ethanol leaf and fruit extracts, respectively. Aqueous leaf extracts produced growth inhibition zones ranging from 10.45 mm (for S. typhi) to 14.02 mm (for E. coli). Ethanol leaf extracts resulted in the lowest Minimum Inhibition Concentration (MIC) of 1.56 mg/mL in E. coli and S. aureus. Therefore, fruits, leaves, and stems of S. incanum can be regarded as good sources of some bioactive compounds. The findings are important for taking measures for conservation and sustainable use of the plant as well as for further elucidation of its phytochemistry and antimicrobial efficacy of its constituents.


Author(s):  
Flávia A. Gonçalves ◽  
Manoel Andrade Neto ◽  
José N. S. Bezerra ◽  
Andrew Macrae ◽  
Oscarina Viana de Sousa ◽  
...  

Guava leaf tea of Psidium guajava Linnaeus is commonly used as a medicine against gastroenteritis and child diarrhea by those who cannot afford or do not have access to antibiotics. This study screened the antimicrobial effect of essential oils and methanol, hexane, ethyl acetate extracts from guava leaves. The extracts were tested against diarrhea-causing bacteria: Staphylococcus aureus, Salmonella spp. and Escherichia coli. Strains that were screened included isolates from seabob shrimp, Xiphopenaeus kroyeri (Heller) and laboratory-type strains. Of the bacteria tested, Staphylococcus aureus strains were most inhibited by the extracts. The methanol extract showed greatest bacterial inhibition. No statistically significant differences were observed between the tested extract concentrations and their effect. The essential oil extract showed inhibitory activity against S. aureus and Salmonella spp. The strains isolated from the shrimp showed some resistance to commercially available antibiotics. These data support the use of guava leaf-made medicines in diarrhea cases where access to commercial antibiotics is restricted. In conclusion, guava leaf extracts and essential oil are very active against S. aureus, thus making up important potential sources of new antimicrobial compounds.


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