scholarly journals Screening Of Antibacterial Activity Of Nepeta Ciliaris Benth. Against Respiratory Tract Pathogens

Author(s):  
Gautam Shiv Shankar ◽  
M Navneet ◽  
Kumar Sanjay ◽  
M Prabhat

The aim of present study was to evaluate the antibacterial potential of various extracts (petroleum ether, acetone, methanol and aqueous) of Nepeta ciliaris against selected respiratory tract pathogens. The extracts from the aerial parts of N. ciliaris at concentration of 200 mg/ml were screened against three gram-positive (Staphylococcus aureus MTCC 1144, Streptococcus pneumoniae MTCC 655 and Streptococcus pyogenes MTCC 442) and one gram-negative (Pseudomonas aeruginosa MTCC 2474) bacterial pathogens. The agar well diffusion method was adopted to examine antibacterial and minimum inhibitory concentration (MIC) values of most effective extracts against the susceptible bacteria. Erythromycin was used as positive control to determine the sensitivity of the strains. Out of the four bacterial species tested, S. pneumoniae was the most susceptible. The acetone extract exhibited maximum activity against all the tested microorganisms while methanol extract showed activity against P. aeruginosa. The MIC values ranged from 40 to 50 mg/ml for all the organisms. The N. ciliaris is potentially a good source of antimicrobial agents. DOI: http://dx.doi.org/10.3126/kuset.v8i1.6049 KUSET 2012; 8(1): 100-103

2014 ◽  
Vol 20 ◽  
pp. 115-123 ◽  
Author(s):  
Kamal Krishna Biswas ◽  
M Omar Faruk ◽  
M Ziaul Amin ◽  
Ranajit Kumar Shaha

Context: Water chest nut (Trapa sp.), an aquatic fruit plant has been used in some area of the rural people of Bangladesh for the treatment of some chronic diseases. Objective: The main objective of this study is to investigate the antibacterial activities of the two varieties (red and green) of water chest nuts. Material and Methods: The antibacterial activities of the methanol extracts of two varieties of water chestnut fruits were studied against a number of human pathogenic bacterial species by using the disc diffusion method. The antibiotic Kanamycin (30 ?g) was used as standard. Results: The methanol extract of red variety of water chestnut showed high antibacterial potential (31 mm) against Bacillus subtilis at concentration of 600 ?g. On the other hand, green variety showed highest antibacterial activities (12 mm) against Staphylococcus aureus at concentration of 600 ?g. In disc diffusion assay, the methanol extract of red variety was found to have a significant antibacterial efficiency as compared to the methanol extract of green variety of water chestnut. Conclusion: These findings pinpoint the efficiency of these extracts to inhibit microbial growth. It may lead to the development of a new phyto-medicine. DOI: http://dx.doi.org/10.3329/jbs.v20i0.17725 J. bio-sci.  20:  115-123, 2012


2012 ◽  
Vol 48 (1) ◽  
pp. 147-154 ◽  
Author(s):  
Antonio Marcos Saraiva ◽  
Cristiane Lopes Saraiva ◽  
Admário Marques Gonçalves ◽  
Rogério Ribeiro Soares ◽  
Fabrício de Oliveira Mendes ◽  
...  

The antimicrobial activity of dry methanol and ethyl acetate extracts for the leaves, bark of the stem, peel of the root, flower, fruit and seed of Caesalpinia pyramidalis Tull. (catingueira) was performed against seventeen isolates of Staphylococcus aureus MRSA multiresistant strains, which included two isolates of S. aureus MSSA and two ATCC strains. The antimicrobial activity was tested by the agar diffusion method and the Minimum Inhibitory Concentration (MIC) was determined. The dry methanol extract of the root showed good antimicrobial activity with a MIC of less than 0.5 mg.mL-1. The dry ethyl acetate extracts exhibited lower antimicrobial activity, which might be explained by solubility problems and less diffusion in the agar medium. Results of the bioautographies also confirmed inhibition halos corresponding to the active substances present in the leaves, as well as in the flower of C. pyramidalis. The phytochemical study of the leaves, bark of the stem, peel of the root, flower and fruit of extracts from C. pyramidalis confirmed the presence of a number of known antimicrobial agents including ursolic acid, quercetin, catechin, ellagic acid, sitosterol, flavonoids, proanthocyanidins and gallic acid.


2020 ◽  
Vol 48 (1) ◽  
pp. 66-78
Author(s):  
Saliha EKŞİ ◽  
Ülkü Zeynep ÜREYEN ESERTAŞ ◽  
Ali Osman KILIÇ ◽  
Nebahat EJDER ◽  
Barış UZUNOK

The rapid rise of resistance causes existing antibiotics to become dysfunctional. Therefore, search for new antimicrobial active ingredients has increased in recent years. In this study, flower extracts of Castanea sativa were examined for antimicrobial and anti-quorum sensing aspects. The antimicrobial properties of methanol, ethyl acetate, ethanol and hexane extracts of C. sativa against some gram-positive and gram-negative bacterial species, as well as yeasts (Candida albicans and Candida parapsilosis) were investigated by the agar well diffusion method. The minimum inhibition concentration (MIC) and minimum bactericidal concentrations (MBC) of C. sativa extracts were also determined. Chromobacterium violaceum ATCC 12472, C. violaceum 35352, C. violaceum VIR07 and C. violaceum CV026 indicator strains were used for determination of the quorum sensing inhibitions, and the Pseudomonas aeruginosa PAO1 strain was used for the swarming tests. Additionally, biofilm inhibition was detected by the spectrophotometric method using the P. aeruginosa PAO1 strain. Methanol, ethanol and ethyl acetate extracts of C. sativa was found to have high antibacterial and antifungal effects, while the methanol extract also had anti-quorum sensing, anti- swarming and biofilm inhibition effects, but no activity was found in the n- hexane extract. To the best of our knowledge this is the first report revealed that methanol extract obtained from C. sativa flowers induced anti-quorum sensing activities mainly inhibited the violacein production, swarming and biofilm formation. The present investigation provided evidence that the C. sativa flower extract maybe a potential source of antimicrobial agents. Therefore, much attention should be paid to C. sativa flower content, which could be used with high efficacy against microorganisms.


1970 ◽  
Vol 46 (4) ◽  
pp. 513-518 ◽  
Author(s):  
V Subhadradevi ◽  
K Asokkumar ◽  
M Umamaheswari ◽  
AT Sivashanmugam ◽  
JR Ushanandhini ◽  
...  

Since ancient times plant as sources of medicinal compounds have continued to play a dominant role in the maintenance of human health. To treat chronic and infectious diseases plants used in traditional medicine contain a wide range of ingredients. In this regard, Cassia auriculata L. (Caesalpiniaceae) is widely used in Ayurvedic medicine as a tonic, astringent and as a remedy for diabetes, conjunctivitis, ulcers, leprosy, skin and liver diseases. The aim of present study was to evaluate the antimicrobial activity of ethanolic extract of Cassia auriculata leaves and flowers (CALE & CAFE). CALE and CAFE exhibited broad spectrum antimicrobial activity against standard strains of Staphylococcus aureus, Escherichia coli and Bacillus subtilis and exhibited no antifungal activity against standard strains of Candida albicans and Aspergillus niger. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) was carried out for CALE and CAFE. The results obtained in the present study indicate that the CALE and CAFE can be a potential source of natural antimicrobial agents. Key words: Cassia auriculata; Antimicrobial activity; Agar well diffusion method. DOI: http://dx.doi.org/10.3329/bjsir.v46i4.9600 BJSIR 2011; 46(4): 513-518


2022 ◽  
Vol 9 ◽  
Author(s):  
Jun Tang ◽  
Xueshuang Huang ◽  
Ming-Hang Cao ◽  
Zhiyan Wang ◽  
Zhiyin Yu ◽  
...  

During a screening for antifungal secondary metabolites, six new mono-/bis-alkenoic acid derivatives (2–7) and one known alkenoic acid derivative (1) were isolated from an endophytic fungi Scopulariopsis candelabrum. Their chemical structures were identified by 1H-NMR, 13C-NMR, 2D NMR, and high-resolution mass spectrometry, as well as comparisons with previously reported literatures. Among them, fusariumesters C‒F (2–5) are bis-alkenoic acid derivatives dimerized by an ester bond, while acetylfusaridioic acid A (6) and fusaridioic acid D (7) are alkenoic acid monomers. All the isolates were submitted to an antifungal assay against Candida albicans and the corn pathogen Exserohilum turcicum using the filter paper agar diffusion method. As a result, only compound 1 decorating with β-lactone ring turned out to be active against these two tested fungi. The broth microdilution assay against Candida albicans showed the minimum inhibitory concentration (MIC) value of 1 to be 20 μg/ml, while the minimum inhibitory concentration value of the positive control (naystatin) was 10 μg/ml. And the half maximal inhibitory concentration (IC50) value (21.23 μg/ml) of 1 against Exserohilum turcicum was determined by analyzing its inhibition effect on the mycelial growth, using cycloheximide (IC50 = 46.70 μg/ml) as the positive control.


2008 ◽  
Vol 61 (3) ◽  
pp. 223 ◽  
Author(s):  
Xin-Hua Liu ◽  
Peng-Cheng Lv ◽  
Bo Li ◽  
Hai-Liang Zhu ◽  
Bao-An Song

A series of novel 1-(acetyl,carboxamide,carbothioamide)substituted-5-(substituted-phenyl)-3-methy-4,5-dihydropyrazole derivatives have been synthesized and characterized by 1H NMR, IR, ESI-MS, and elemental analysis. Compounds 6h and 6q were further characterized by single crystal X-ray structural analysis. All of the compounds have been screened for their antibacterial potential in vitro against Bacillus subtilis ATCC 6633, Escherichia coli ATCC 35218, Pseudomonas fluorescens ATCC 13525, and Staphylococcus aureus ATCC 6538. Among the tested compounds, some of them display significant activity against the tested strains, and compounds 5ac and 6h show potent activity with a minimum inhibitory concentration value of 1.562 μg mL–1 against B. subtilis ATCC 6633, which is comparable to the positive control penicillin. Structure–effect relationships are also discussed based on the experimental data.


Author(s):  
Mohammad Hassan Moshafi ◽  
Ali Peymani ◽  
Alireza Foroumadi ◽  
Mohammad Reza Zabihi ◽  
Farzad Doostishoar

Introduction: Nitrofurans and nitroimidazoles are broad-spectrum antimicrobial agents, which affect the microbial DNA. The aim of the present study was to evaluate the new derivatives of these two groups of antimicrobials against certain Gram-positive and Gram-negative bacterial strains. Materials and Methods: Seven new derivatives of nitrofurans and nitroimidazoles were synthesized, and 6.4 mg of each derivative was dissolved in dimethyl sulfoxide. Then, 8 serial dilutions (0.5, 1, 2, 4, 8, 16, 32, and 64 μg/ml) of each derivative was prepared using Muller-Hinton broth, and the minimum inhibitory concentration for each derivative was measured and compared to ciprofloxacin (standard). Results: All the derivatives had no antibacterial effects against Gram-negative bacteria (minimum inhibitory concentration > 64 μg/ml); only 2-(5-nitro-2-furyl)-5-(n-pentylsulfunyl)-1,3,4-thiadiazole exhibited mild antibacterial effects against Klebsiella pneumonia (minimum inhibitory concentration of 16-32 μg/ml). The antibacterial effects of the derivatives against Gram-positive bacteria also showed variations from complete inhibition of the growth of Staphylococcus epidermidis and Bacillus subtilis (minimum inhibitory concentration < 0.5 μg/ml) by 2-(5-nitro-2-furyl)-5-(n-buthylthio)-1,3,4-thiadiazole to no inhibition of S. epidermidis and streptococcus pyogenes. Conclusion: These compounds have weak antibacterial effects; only two derivatives showed antibacterial effects similar to that of the positive control.


2021 ◽  
Vol 12 (6) ◽  
pp. 87-90
Author(s):  
Virendra Vaishnav ◽  
Debasish Sahoo ◽  
Tanushree Chatterjee

Medicinal Plants are the good source of natural antimicrobial agents. The main aim of present study was to evaluate the antibacterial activity of stem and root of Rauwolfia serpentina against six microorganism, Powdered stem and root of plant were extracted with acetone, chloroform and methanol and streptomycin used as positive control. The antibacterial activity of Rauwolfia serpentine was detected by using disc diffusion method and agar well diffusion method on the following bacteria- Bacillus cereus, Staphylococcus aureus, Bacillus fusiformis, Escherichia coli, Pseudomonas aeruginosa and P. luminescens. The experiment reported that R. serpentina Root methanol extract shown 14.86 ± 1.11 highest antibacterial activity against Pseudomonas aeruginosa through well diffusion method. Whereas root chloroform recorded 13.46 ± 1.28 highest antibacterial activity against E. coli through disc diffusion method, maximum zone of inhibition 22.66±0.52 mm was found for the positive control, streptomycin through well diffusion method. Further studies should be undertaken to reveal the correct mechanism of action of antimicrobial effect to identify the active ingredients which can be used in drug development program.


2016 ◽  
Vol 2 (2) ◽  
pp. 49
Author(s):  
Sahar Omidpanah ◽  
Abbas Hadjiakhondi ◽  
Azadeh Manayi

Researchers have been trying to develop new broad-spectrum antibiotics against the infectious diseases caused by bacteria, fungi, viruses, and parasites for many decades. Prolonged usage of the antibiotics has led to the emergence of drug resistance among bacteria; therefore, there is a tremendous need for novel antimicrobial agents from different sources such as plants which are used in traditional medicine. The aim of this study was to evaluate antibacterial effect of <em>Achillea tenuifolia</em>.<em> </em>The plant material was extracted by maceration method using methanol three times at room temperature. The extract was concentrated after removing the solvent by rotary evaporator and then lyophilized using freeze dryer. Inhibitory effect of the extract was examined against four standard bacteria strains and two isolated strains from diseased hen using disk diffusion method and microdilution method to evaluate their inhibition zone diameter (IZD) and minimum inhibitory concentration (MIC), respectively. The results showed that the extract of the plant was active against standard strains including <em>Escherichia coli</em>, <em>Pseudomonas aeruginosa</em>, <em>Staphylococcus aureus </em>and <em>Enterococcus faecalis </em>with IZDs of 10.3±0.5, 14±0.0, 12±0.0 and 11.6±0.5, respectively.<strong> </strong>However, growths of isolated strains were not inhibited in the presence of the extract. Although, the growths of isolated strains were not inhibited by the plant extract, the standard strains were moderately susceptible to the extract; among those <em>P. aeroginosa</em> was more sensible than other tested strains


Author(s):  
Vifin Putri Rahmawati ◽  
Chylen Setiyo Rini

Plants have many chemical components. The use of natural ingredients as an alternative treatment in dealing with diseases, especially acne. One of them is mango (Mangifera indica L.) varieties of apples obtained at the Larangan Main Market in Sidoarjo. This study aims to determine the potential of infusion and maceration of mango skin varieties in inhibiting Pseudomonas aeruginosa and Propionibactrium acne at various concentrations. This antibacterial potential test was carried out using the diffusion method of the wells. The antibacterial potential is characterized by the formation of a clear zone around the well called the inhibition zone. This study uses 10 concentrations namely 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% and Clindamycin as positive control and aquades as negative control. Based on the results of the Two Way ANOVA test data obtained were not normally distributed, therefore a comparison test was performed using the Kruskal-Wallis test with a sign value (α <0.05). This showed that there were significant differences in the use of various concentrations. The maceration extract concentration of 100% is the best concentration to form a zone of inhibition against P. aeruginosa  of 17.9 mm and P. acne bacteria of 13.2 mm. The results of the infusion extract concentration did not form inhibitory zones in both of P. aeruginosa and P. acnes.


Sign in / Sign up

Export Citation Format

Share Document