Antibacterial activity of ethanolic extracts of selected medicinal plants against human pathogens

2011 ◽  
Vol 1 (1) ◽  
pp. S76-S78 ◽  
Author(s):  
Joy Jeba Malar T Renisheya ◽  
M Johnson ◽  
Uthith M Mary ◽  
A Arthy
2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Bishnu P. Marasini ◽  
Pankaj Baral ◽  
Pratibha Aryal ◽  
Kashi R. Ghimire ◽  
Sanjiv Neupane ◽  
...  

The worldwide increase of multidrug resistance in both community- and health-care associated bacterial infections has impaired the current antimicrobial therapy, warranting the search for other alternatives. We aimed to find thein vitroantibacterial activity of ethanolic extracts of 16 different traditionally used medicinal plants of Nepal against 13 clinical and 2 reference bacterial species using microbroth dilution method. The evaluated plants species were found to exert a range ofin vitrogrowth inhibitory action against the tested bacterial species, andCynodon dactylonwas found to exhibit moderate inhibitory action against 13 bacterial species including methicillin-resistantStaphylococcus aureus, imipenem-resistantPseudomonas aeruginosa, multidrug-resistantSalmonella typhi, andS. typhimurium. The minimum inhibitory concentration (MIC) values of tested ethanolic extracts were found from 31 to >25,000 μg/mL. Notably, ethanolic extracts ofCinnamomum camphora, Curculigo orchioides, andCurcuma longaexhibited the highest antibacterial activity againstS. pyogeneswith a MIC of 49, 49, and 195 μg/mL, respectively; whereas chloroform fraction ofCynodon dactylonexhibited best antibacterial activity againstS. aureuswith a MIC of 31 μg/mL. Among all,C. dactylon, C. camphora, C. orchioides, andC. longaplant extracts displayed a potential antibacterial activity of MIC < 100 μg/mL.


1970 ◽  
Vol 18 ◽  
pp. 128-133 ◽  
Author(s):  
MTH Molla ◽  
MS Ahsan ◽  
MT Alam ◽  
ME Haque

Context: Development of resistance in human pathogens against conventional antibiotic necessitates searching indigenous medicinal plants having antibacterial property. Seven medicinal plants used actively in folklore, ayurvedic and traditional system of medicine were selected for the evaluation of their antimicrobial activity for this study.   Objectives: Evaluation of the effectiveness of some medicinal plant extracts against four Gram-positive and five Gram-negative bacteria.  Materials and Methods: The antibacterial activity of the crude ethanolic extracts obtained from the leaves of seven medicinal plants; viz., Andrographis paniculata, Catharanthus roseus, Adhatoda vasica, Vitex vegundo, Aloe vera, Flacortia ramontchi and Nyctanthes arbortristis were tested against nine bacteria at concentrations of 300-, 400- and 500 μg/ml. Standard antibiotic disc kanamycin (30μg/ml) was used for comparison. The minimum inhibitory concentration (MIC) of ethanolic extracts of the leaves of these medicinal plants were determined by testing the extracts on four Gram-positive and five Gram-negative bacteria by serial tube dilution method.   Results: All the extracts have notable antimicrobial activities against the test organisms. The ethanolic extracts of the leaves showed the highest antimicrobial activities against Bacillus megaterium and Shigella dysenteriae for An. paniculata, Ad. vasica and Al. vera; Bacillus subtilis and Salmonella typhi for C. roseus and N. arbortristis; Staphylociccus aureus and Salmonella typhi for V. vegundo; and Bacillus subtilis and Shigella sonnei for F. ramontchi respectively. The extract of the plants had MIC values ranging from 32 to 128 mg/ml. All plant extracts showed no MIC against Shigella shiga and against Sarcina lutea only C. roseus showed MIC 128 mg/ml.   Conclusion: The results revealed that the ethanolic extracts of the plants under present investigation have notable antimicrobial activities.   Keywords: medicinal plants; antimicrobial screening; MIC; bacteria. DOI: http://dx.doi.org/10.3329/jbs.v18i0.8788 JBS 2010; 18(0): 128-133


2017 ◽  
Author(s):  
Luong Thi My Ngan ◽  
Pham Phuong Dung ◽  
Nguyen Vang Thi Yen Nhi ◽  
Nguyen van Minh Hoang ◽  
Tran Trung Hieu

2017 ◽  
Vol 5 (1) ◽  
pp. 62 ◽  
Author(s):  
Stephen Enabulele ◽  
Oluwatosin Amusa ◽  
Eseosa Uwadiae

The leaves of two medicinal plants namely; Morinda lucida and Nauclea latifolia were investigated for their antibacterial, mineral and phytochemical properties. Results of the study showed that the aqueous and ethanolic extract of the two leaves had significant antibacterial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes and Proteus mirabilis. The biologically active constituents present in the extracts were cardiac glycosides, tannins, saponin, coumarins, reducing sugar, terpenoids, alkaloids, steroids and flavonoids. The percentage yield extracts of the respective plants were Morinda lucida leaves 12.9% for ethanol and 9.0% for aqueous extracts while Nauclea latifolia had 12.1% for ethanol and 8.4% for aqueous extracts. Results of the antibacterial activity analysis revealed that the ethanolic extracts of the two medicinal plants at different concentrations were more active against the test organisms named above than the aqueous extracts. The MIC values for the ethanolic extracts ranged between 25.0 and 100.0 mg/ml while that of aqueous extract ranged between 50.0 and 100.0 mg/ml. The MBC values for ethanolic extract ranged between 50.0 and 100mg/ml while that of aqueous extracts also ranged between 50.0 and 100mg/ml. Analysis of the mineral content of the plant leaves shows that they were rich in potassium and calcium. This study confirms that the leaf extracts have some reasonable level of antimicrobial activity and appreciable amounts of mineral content which could be beneficial to human health. The findings from this work can be further exploited for isolation and characterization of novel Phytochemical compounds which could be used in the treatment of infectious diseases especially in light of the emergence of drug-resistant microorganisms and the need to produce new effective antimicrobial agents.


2018 ◽  
Vol 41 (2) ◽  
pp. 38-47
Author(s):  
Huda Abdal-Hadei Ali Al-Nasrawi

     This study aimed to evaluate-the inhibitory effects of ethanolic and-chloroformic-extracts of local medicinal plants as Oak (Quercus-acuta), Thyme (Thymus vulgaris) and Cinnamon (Cinnamomum-zeylanicum) prepared in different concentrations (50, 100, 200 and 400 mg/ml) against the growth of Listeria-monocytogenes isolated from infected humans and animals and comparing their activity with effectiveness of the standard antibiotics. The results showed detection of Listeria-monocytogenes in 3 of (50) blood samples collected from aborted woman making 6% samples, while the detection rates of Listeria-monocytogenes in milk samples collected from sheep and cattle were 4% (4/100) and 9.16% (11/120) respectively. The ethanolic and-chloroformic extracts-of Thyme as well as, chloroformic extracts of Oak and Cinnamon  at concentrations (50 and 100 mg/ml) showed significant antibacterial activity against the growth of Listeria-monocytogenes isolates from humans, while the ethanolic extracts  of Oak and Cinnamon did not show any antibacterial activity against the growth of same bacterial isolates. The ethanolic and chloroformic extracts of Thyme, as well as chloroformic extracts of Cinnamon at concentrations (50 and 100 mg/ml) showed antibacterial activity against growth of Listeria monocytogenes isolates of cattle, while ethanolic and chloroformic extracts of Oak and ethanolic- extracts of Cinnamon did not show any activity against growth of the same isolates. The results showed that all extracts have antibacterial activity against growth of-Listeria monocytogenes isolates-of sheep, except ethanolic extracts of Cinnamon at all tested concentration; as well, the chloroformic extracts of Thyme at concentrations (5o and 100 mg/ml) didn’t show any inhibitory activity for the growing of the same Listeria. monocytogenes isolates. Most of the results showed high antibacterial activity against growth of all Listeria .monocytogenes isolates from human and animals compared with negative control and this depends on their inhibition zones. In this study, we used six standard antibiotics as a positive control for Listeria monocytogenes, where rifampin. (5mcg),-chloramphenicol.(10mcg), streptomycin (25 mcg) and amoxicillin/clavulanic acid-(20/10mcg) were effective in inhibition the growth of all L. monocytogenes isolates from human and animals, while cefotaxime. (10 mcg) and novobiocin. (30 mcg) showed no inhibitory effects against growth of all L. monocytogenes isolates.


2013 ◽  
Vol 6 (7) ◽  
pp. 331-339 ◽  
Author(s):  
Saeide Saeidi ◽  
Parisa Shojaei ◽  
Saphora Bazi ◽  
Nima Sanadgol

2020 ◽  
Vol 18 ◽  
Author(s):  
Mulugeta Mulat ◽  
Fazlurrahman Khan ◽  
Archana Pandita

Background: Medicinal plants have been used for treatments of various health ailments and the practices as a remedial back to thousands of years. Currently, plant-derived compounds used as alternative ways of treatment for multidrug-resistant pathogens. Objective: In the present study, various parts of six medical plants such as Solanum nigrum, Azadirachta indica, Vitex negundo, Mentha arvensis, Gloriosa superba, and Ocimum sanctum were extracted for obtaining biological active constituents. Methods: Soxhlet method of extraction was used for obtaining crude extracts. Agar disc diffusion and 96-well plate spectroscopic reading were used to detect the extract’s antibacterial and antibiofilm properties. Results: The obtained extracts were tested for antimicrobial and antibiofilm properties at 25 mg/mL concentrations. Maximum antibacterial activity was observed in O. sanctum chloroform extract (TUCE) against Staphylococcus aureus (24.33±1.52 mm), S. nigrum acetone extract (MAAC) against Salmonella Typhimurium (12.6 ± 1.5 mm) and Pseudomonas aeruginosa (15.0 ±2.0 mm). Only TUCE exhibited antibacterial activity at least a minimum inhibitory concentration of 0.781 mg/mL. Better antibiofilm activities were also exhibited by petroleum extracts of G. superba (KAPE) and S. nigrum (MAPE) against Escherichia coli, S. Typhimurium, P. aeruginosa and S. aureus. Moreover, S. nigrum acetone extract (MAAC) and O. sanctum chloroform extract (TUCE) were showed anti-swarming activity with a reduction of motility 56.3% against P. aeruginosa and 37.2% against S. aureus. MAAC also inhibits Las A activity (63.3% reduction) in P. aeruginosa. Conclusion: Extracts of TUCE, MAAC, MAPE, and KAPE were exhibited antibacterial and antibiofilm properties against the Gram-positive and Gram-negative pathogenic bacteria. GCMS identified chemical constituents are responsible for being biologically active.


Sign in / Sign up

Export Citation Format

Share Document