IN VITRO ANTIMICROBIAL ACTIVITY OF ROOT EXTRACT OF CLITORIA TERNATEA

Objective: Infections caused by Gram-negative bacteria are important causes of morbidity and mortality. Extracts of plants and herbs such as Clitorea ternatea are used as diuretic. This work attempts to find out antimicrobial activity of aqueous and alcoholic extract of C. ternatea roots against Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), clinical strains of Klebsiella pneumoniae, and Candida albicans.Methods: The agar well-diffusion method was done using Mueller Hinton agar and Sabouraud’s dextrose agar. The microorganism grown in peptone water was inoculated into culture medium. 4 mm diameter well punched into the agar was filled with 20 μl of aqueous and alcoholic root extracts C. ternatea extracts in various concentrations (100-25 μg/ml). The plates were incubated and antimicrobial activity was evaluated.Results: Aqueous root extract of C. ternatea with the concentration of 100 μg/ml showed zone of inhibition against E. coli (ATCC 25922) 18 mm, P. aeruginosa (ATCC 27853) 14 mm, multidrug resistant strain of K. pneumoniae 15 mm. Alcoholic extract of C. ternatea with the concentration of 100 μg/ml showed zone of inhibition of 35 mm against E. coli (ATCC 25922), P. aeruginosa (ATCC 27853) 22 mm, and multidrug resistant strain of K. pneumoniae 28 mm. C. albicanswas resistant to both extract of C. ternatea root. Conclusions: Alcoholic extract of C. ternatea is a better antibacterial agent against multidrug resistant Klebsiella species and other Gram-negative pathogens. Further, studies are required to identify active substances from the alcoholic extracts of C. ternatea for treating infections.

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Synthesis and Antimicrobial Activity of Piperine Analogues Containing 1,2,4-Triazole Ring

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21876 ◽

2019 ◽

Vol 31 (5) ◽

pp. 1077-1080

Author(s):

Kottakki Naveen Kumar ◽

Karteek Rao Amperayani ◽

V. Ravi Sankar Ummdi ◽

Uma Devi Parimi

Keyword(s):

Antimicrobial Activity ◽

Triazole Ring ◽

Diffusion Method ◽

Moderate Activity ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Antibacterial Study ◽

Gram Negative ◽

E Coli ◽

Micro Organisms

A series 1,2,4-triazole piperine analogues (TP1-TP6) were designed and synthesized. The structures were confirmed using 1H NMR and 13C NMR. Antibacterial study was done using Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative micro-organisms (E. coli and Pseudomonas aeruginosa) by disc diffusion method. Compound containing chloro substitution (TP6) showed the highest effect, while compound TP1, TP3, TP4, TP5 showed the moderate activity.

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Phytochemical Screening and Antimicrobial Activity Of Asparagus Racemosus Willd. and Asparagus Curillus Buch.-Ham. Ex Roxb

Journal of Natural History Museum ◽

10.3126/jnhm.v29i0.19041 ◽

2018 ◽

Vol 29 ◽

pp. 91-102

Author(s):

Rose Shrestha ◽

Astha Shakya ◽

Krishna Kumar Shrestha

Keyword(s):

Antimicrobial Activity ◽

Aqueous Extract ◽

Ethanolic Extract ◽

Salmonella Typhi ◽

Diffusion Method ◽

Asparagus Racemosus ◽

Alcoholic Extract ◽

Phytochemical Screening ◽

Zone Of Inhibition ◽

Different Strains

Asparagus racemosus Willd. is an important medicinal plant of tropical and subtropical regions of Nepal and India. Its medicinal usage has been reported in the Indian and British Pharmacopoeias and in traditional systems of medicine such as Ayurveda, Unani, and Siddha. Asparagus curillus Buch-Ham.ex Roxb. is also one of the species found in higher altitude of Nepal. Its roots are used as substitute for A. racemosus. Phytochemical investigation was done for these two species of Nepalese Asparagus as per Methodology for Analysis of Vegetable Drugs by I. Ciulei.1982. Phytochemical screening revealed the presence of coumarin, flavonoid, catecholic tannin, reducing compound in alcoholic extract of A. racemosus while its aqueous extract revealed polyuronoid, reducing compound, polyoses, saponin, gallic tannin, catecholic tannin, etc. Similarly, alcoholic extract of A. curillus revealed catecholic tannin, reducing compound and aqueous extract revealed polyuronoid polyoses, saponin, gallic tannin as main phytochemical compounds. Comparative antimicrobial activity of ethanolic extract of these two species has been evaluated using Kirby-Bauer Agar well diffusion method. The extracts were screened for their antimicrobial activity on nine different strains of human pathogenic microorganisms such as Escherichia coli, Salmonella typhi, Bacillus subtilis, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalies, Saccharomyces cerevisiae and Candida albicans. Among them A. racemosus has shown selected antimicrobial effects against B. subtilis, E. coli, E. faecalis, S. cerevisiae and C. albicans with zone of inhibition of 25 mm in an average. While A. curillus showed effects on S. cerevisiae and C. albicans only with zone of inhibition about12 mm.J. Nat. Hist. Mus. Vol. 29, 2015, Page: 91-102

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Synthesis, Characterisation and Antimicrobial Potential of Novel N-Alkylated Pyrrole Derivatives of Chitosan

Bioscience Biotechnology Research Communications ◽

10.21786/bbrc/14.4.52 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1730-1736

Author(s):

Kalpana. P. R

Keyword(s):

Antimicrobial Activity ◽

Inhibitory Effect ◽

Maximum Activity ◽

Diffusion Method ◽

Zone Of Inhibition ◽

Pyrrole Derivatives ◽

Structural Modifications ◽

E Coli ◽

Antimicrobial Potential ◽

Derivatives Of

Chitosan, a cationic biopolymer is a major derivative of chitin. It is biocompatible, non-toxic and environ-friendly material and has broad spectrum antimicrobial activity. However, it is less effective in neutral or basic conditions due to its solubility only in acidic medium. Therefore, chemical modification with suitable groups is necessary to enhance the potency of chitosan. The present study was mainly conducted to explore the effect of structural modifications on antimicrobial potential of chitosan. N-Methyl, N-Ethyl and N-Propyl pyrrole were reacted with N-chloroacyl-6-O-triphenylmethylchitosan prepared by stepwise modification of chitosan to form N-Methyl, N-Ethyl and N-Propyl pyrrole derivatives of chitosan. Structural characterization of these pyrrole derivatives was done by IR, NMR, XRD, DSC and Elemental Analysis. The gram-negative bacterium Escherichia coli, gram-positive bacterium Staphylococcus aureus were selected for antibacterial activity and the fungus C. albicans was selected for antifungal activity by agar diffusion method and MIC method. Antimicrobial activity of the N-Methyl, N-Ethyl and N-Propyl pyrrole derivatives on E. coli, S. aureus and C. albicans showed an inhibitory effect on all the organisms. The potency of inhibition was found to be varied with the substitutions. The maximum activity was shown by N-pyrrolylpropylchitosan against E. coli (zone of inhibition 1.2±0.05cm, MIC 0.15±0.03mg/ml), S. aureus (zone of inhibition 1.4±0.03cm, MIC 0.15±0.01mg/ml), C. albicans (zone of inhibition 0.8±0.03cm, MIC 0.2±0.03mg/ml). The study also confirmed that all the three derivatives exhibited higher inhibition than that of chitosan against E. coli (zone of inhibition 0.7±0.03cm, MIC 0.09±0.02mg/ml), S. aureus (zone of inhibition 0.8±0.03cm, MIC 0.09±0.02mg/ml), C. albicans (zone of inhibition 0.6±0.03cm, MIC 0.09±0.03mg/ml). Results demonstrated that these three N-alkylpyrrole chitosan derivatives exhibited improved potency and hence can have the more applicability as antimicrobials.

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Antimicrobial activity of Commercial essential oils on human pathogens

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00771 ◽

2021 ◽

pp. 4440-4444

Author(s):

B. R. Malathy ◽

Sweetlin Ajitha P ◽

Sangeetha K. S ◽

Swetha Thampy ◽

Kamala G

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Pathogenic Bacteria ◽

Steam Distillation ◽

Diffusion Method ◽

Human Pathogens ◽

Aromatic Plants ◽

Zone Of Inhibition ◽

E Coli ◽

Development Of Resistance

Essential oils (EOs) are natural extracts from the seeds, stems, roots, flowers, bark and other parts of the plant prepared by steam distillation. They are complex, volatile, natural compounds formed by aromatic plants as secondary metabolites. They are known for their bactericidal, virucidal, fungicidal, sedative, anti-inflammatory, analgesic, spasmolytic and locally anesthetic properties. They are generally composed of a combination of substances like terpenes, phenolics, aldehydes or alcohols. The complex composition and different mechanisms of action of EOs may be an advantage over other antimicrobials to prevent the development of resistance of pathogenic bacteria. With this background, the aim of this study was to evaluate the antimicrobial activity of five essential oils like basil, lime, rosemary, thyme and canada balsam against 14 microbes. The effects of essential oil on the selected microbes were determined by agar well diffusion method. The zone of inhibition was observed and measured in millimeter. Essential oils which showed inhibitory diameter >15 mm were further tested to determine the minimum inhibitory concentration (MIC). S. aureus, E. coli, S. mutans, S. sanguinis, C. albicans and M. furfur were inhibited by all essential oils. K. pneumoniae, P. aeruginosa and E .faecalis were inhibited only by thyme and not by other essential oils. The MIC values ranged from 50% to 0.10%. The least MIC value of 0.10% was shown by thyme and basil to S. aureus, thyme to E.coli and all essential oils against C. albicans except lime.

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SEARCH FOR ANTIMICROBIAL AGENTS: QUINOXALINE AS A PROMISING TARGET

INDIAN DRUGS ◽

10.53879/id.54.07.10919 ◽

2017 ◽

Vol 54 (07) ◽

pp. 5-9

Author(s):

R. G Ingle ◽

◽

S. J. Wadher

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Agents ◽

Disk Diffusion ◽

Diffusion Method ◽

Bacterial Strains ◽

Disk Diffusion Method ◽

Gram Negative ◽

E Coli ◽

Promising Target ◽

Quinoxaline Derivatives

A set of ten new 2,3-diphenyl-6-sulfonamido quinoxaline derivatives was synthesized and screened for antimicrobial activity by disk diffusion method. Test derivatives R3, R5, R’’1 and R’’2 show promising results against bacterial strains S. aureus gram positive and E. coli gram negative organism with the concentration 1000 μg/mL in disk diffusion method. Rest of the derivatives show sensitivity against the same organisms. All the synthesized derivatives were confirmed by their spectral data.

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Gram-negative bacilli causing infections in an intensive care unit of a tertiary care hospital in Istanbul, Turkey

The Journal of Infection in Developing Countries ◽

10.3855/jidc.4277 ◽

2014 ◽

Vol 8 (05) ◽

pp. 597-604 ◽

Cited By ~ 1

Author(s):

Seniha Senbayrak Akcay ◽

Asuman Inan ◽

Simin Cevan ◽

Ayse Nilufer Ozaydın ◽

Naz Cobanoglu ◽

...

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Tertiary Care ◽

Multidrug Resistant ◽

Diffusion Method ◽

Care Hospital ◽

Chi Square ◽

Disk Diffusion Method ◽

Gram Negative ◽

E Coli

Introduction: This study aimed to demonstrate the changing epidemiology of infecting microorganisms and their long-term resistance profiles and to describe the microbiological point of view in anti-infective management of intensive care unit (ICU) patients. Methodology: A total of 5,690 isolates of Gram-negative bacilli were included in this study. Antibiotic susceptibility was tested using the disk diffusion method and Vitek 2 system. Chi-square tests were used for hypothesis testing. Results: The most frequently isolated organisms were A. baumannii (37.3%), P. aeruginosa (30.3%), Enterobacter spp. (10.4%), E. coli (10.4%), and Klebsiella spp. (8.9%). A. baumannii was the most frequently isolated organism from the respiratory tract (43.4%); the susceptibility rates for imipenem and meropenem decreased to 7% and 6% (p < 0.0001), respectively. The percentage of multidrug-resistant (MDR) A. baumannii isolates continuously increased from 18.7% in 2004 to 69% in 2011 (p < 0.0001), whereas MDR P. aeruginosa isolates increased from 1.5% to 22% (p < 0.0001). Carbapenem-resistant Klebsiella isolates emerged in 2010 and increased to 20% in the next year. The rates of ESBL-producing Enterobacteriaceae in the ICU was very high in 2011 – 50% for E. coli and 80% for Klebsiella strains. Conclusion: The most common isolated Gram-negative bacillus in our study was A. baumannii and that the prevalence of MDR isolates has increased markedly over. Accordingly, the comparison of antibiotic resistance of other pathogens in 2004 and 2011 displayed an increasing trend. These data imply the urgent need for new and effective strategies in our hospital and in the region.

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Cefepime/tazobactam as a new treatment option for multidrug resistant gram negative bacilli

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20192512 ◽

2019 ◽

Vol 7 (6) ◽

pp. 2278

Author(s):

Roshni Agarwal ◽

Vaibhav Agarwal ◽

Anjali Tewari ◽

Parwati Upadhyay

Keyword(s):

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Multidrug Resistant ◽

Diffusion Method ◽

Resistant Bacteria ◽

In Vitro Susceptibility ◽

Gram Negative ◽

E Coli ◽

New Treatment

Background: Every time an antibiotic is used, whether appropriately or not, the probability of the development and spread of antibiotic resistant bacteria is increased. Thus, multidrug resistant bacteria particularly ESBL (Extended spectrum βlactamase), Amp C and carbapenemases producing gram negative bacilli have emerged as a major health problem all over the world. Considering new treatment options as a carbapenems sparing and resistance prevention modality, this study was aimed to know the in vitro susceptibility pattern of Cefepime/Tazobactam (CPM/TZ) in comparison to other β-Lactam/ β-Lactamase inhibitors (BL/BLI) and carbapenems against GNB.Methods: A prospective study was conducted on all clinical samples received for a period of about 1 year. Identification and susceptibility of all isolates was done by Vitek 2 Compact system. Susceptibility of CPM/ TZ was done by disc diffusion method on the basis of CLSI guidelines. Both fermenters (E. coli and Klebsiella pneumoniae) and non-fermenters (Acintobacter baumanii and Pseudomonas aeruginosa) were included in the study.Results: Out of 550 GNB isolates the most common was E. coli (61.8%), Acintobacter baumanii (16%), Klebsiella pneumoniae (14.9%) and Pseudomonas aeruginosa (7.3%). Cefepime/tazobactam had a much higher susceptibility of 68% compared to cefepime (28%). Among the BL/BLI combinations tested cefepime/tazobactam (68%) showed the maximum percentage of susceptibility followed by cefoperazone/sulbactam (61.5%) and piperacillin/tazobactam (57.6%). Amongst all GNB isolates cefepime/tazobactam (68%) sensitivity was very much comparable to imipenem (71.8%) and meropenem (69.6%).Conclusions: CPM/TZ exhibited the best in vitro activity in comparison to the other BL/BLI. This new combination of cefepime/tazobactam appears to be a promising alternative therapeutic option to carbapenems. Clinical studies are needed to confirm this in vitro study result.

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Addition of L-cysteine to the N- or C-terminus of the all-D-enantiomer [D(KLAKLAK)2] increases antimicrobial activities against multidrug-resistant Pseudomonas aeruginosa, Acinetobacter baumannii and Escherichia coli

PeerJ ◽

10.7717/peerj.10176 ◽

2020 ◽

Vol 8 ◽

pp. e10176

Author(s):

Maki K. Ohno ◽

Teruo Kirikae ◽

Eisaku Yoshihara ◽

Fumiko Kirikae ◽

Isao Ishida

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Synergistic Effects ◽

Multidrug Resistant ◽

Antimicrobial Activities ◽

Cysteine Residue ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

C Terminus

Background Antimicrobial peptides have a broad spectrum of antimicrobial activities and are attracting attention as promising next-generation antibiotics against multidrug-resistant (MDR) bacteria. The all-d-enantiomer [D(KLAKLAK)2] has been reported to have antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa, and to be resistant to protein degradation in bacteria because it is composed of D-enantiomer compounds. In this study, we demonstrated that modification of [D(KLAKLAK)2] by the addition of an L-cysteine residue to its N- or C- terminus markedly enhanced its antimicrobial activities against Gram-negative bacteria such as MDR Acinetobacter baumannii, E. coli, and P. aeruginosa. Methods The peptides [D(KLAKLAK)2] (DP), DP to which L-cysteine was added at the N-terminus C-DP, and DP to which L-cysteine was added at the C-terminus DP-C, were synthesized at >95% purity. The minimum inhibitory concentrations of peptides and antibiotics were determined by the broth microdilution method. The synergistic effects of the peptides and the antibiotics against MDR P. aeruginosa were evaluated using the checkerboard dilution method. In order to assess how these peptides affect the survival of human cells, cell viability was determined using a Cell Counting Kit-8. Results C-DP and DP-C enhanced the antimicrobial activities of the peptide against MDR Gram-negative bacteria, including A. baumannii, E. coli, and P. aeruginosa. The antimicrobial activity of DP-C was greater than that of C-DP, with these peptides also having antimicrobial activity against drug-susceptible P. aeruginosa and drug-resistant P. aeruginosa overexpressing the efflux pump components. C-DP and DP-C also showed antimicrobial activity against colistin-resistant E. coli harboring mcr-1, which encodes a lipid A modifying enzyme. DP-C showed synergistic antimicrobial activity against MDR P. aeruginosa when combined with colistin. The LD50 of DP-C against a human cell line HepG2 was six times higher than the MIC of DP-C against MDR P. aeruginosa. The LD50 of DP-C was not altered by incubation with low-dose colistin. Conclusion Attachment of an L-cysteine residue to the N- or C-terminus of [D(KLAKLAK)2] enhanced its antimicrobial activity against A. baumannii, E. coli, and P. aeruginosa. The combination of C-DP or DP-C and colistin had synergistic effects against MDR P. aeruginosa. In addition, DP-C and C-DP showed much stronger antimicrobial activity against MDR A. baumannii and E. coli than against P. aeruginosa.

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Synthesis, Characterization and Antimicrobial Activity of N-2-(4-Chlorophenyl)acetyl Derivatives of (S)-Amino Acids

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22416 ◽

2019 ◽

Vol 32 (2) ◽

pp. 381-384

Author(s):

G. Venkateshappa ◽

P. Raghavendra Kumar ◽

Krishna2

Keyword(s):

Amino Acids ◽

Antimicrobial Activity ◽

Diffusion Method ◽

Gram Negative ◽

E Coli ◽

Ft Ir ◽

Bacteria And Fungi ◽

Derivatives Of ◽

Ft Ir Spectroscopy ◽

Agar Well Diffusion Method

This paper reports the synthesis, characterization and antibacterial activity of N-2-(4-chlorophenyl)acetyl derivatives of various (S)-amino acids such as (S)-alanine, (S)-phenylalanine, (S)-leucine, (S)-methionine, (S)-proline and (S)-tryptophane. These compounds have been successfully synthesized and their structures were confirmed by 1H NMR and 13C NMR and FT-IR spectroscopy. The antimicrobial activity of these six (S)-amino acids derivatives have been evaluated by the agar well diffusion method against pathogens both Gram-positive (S. aureus) and Gram-negative (K. aerogenes, E. coli and P. desmolyticumas) bacteria and fungi (A. flavus and C. albicans). All these compounds have shown mild to moderate antimicrobial activity.

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Bactericidal and Fungicidal Activity of Polyetherguanidinium Chloride

Mikrobiolohichnyi Zhurnal ◽

10.15407/microbiolj83.01.049 ◽

2021 ◽

Vol 83 (1) ◽

pp. 49-57

Author(s):

M.Ya. Vortman ◽

◽

Yu.B. Pysmenna ◽

A.I. Chuenko ◽

A.V. Rudenko ◽

...

Keyword(s):

Antimicrobial Activity ◽

Fungicidal Activity ◽

Heterotrophic Bacteria ◽

Diffusion Method ◽

Klebsiella Pneumonia ◽

Microscopic Fungi ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Wide Range

There is information in the literature about the salts of polyhexamethylene guanidine (PGMG), which are effective biocidal and sterilizing drugs and disinfectants due to the wide range of their antimicrobial activity against gram-positive and gram-negative bacteria (including Mycobacterium tuberculosis), viruses, and fungi. The aim of this work is to study the bactericidal and fungicidal activity of the synthesized polyetherguanidinium chloride against a number of bacteria and microscopic fungi. Methods. Cultivation of microorganisms. Bacteria were grown on meat-peptone agar for 48 hours at a temperature of 28±2°C. Test cultures of micromycetes were cultured on beer wort agar (6°B), incubated for 14 days in a thermostat at a temperature of 28±2°C. Antimicrobial activity of newly synthesized polyetherguanidinium chloride was determined by standard disco-diffusion method, and fungicidal activity was determined by agar diffusion method. Results. The synthesis of polyetherguanidinium chloride was carried out in two stages. The first stage was the synthesis of a guanidinium-containing oligoether with terminal guanidine moieties by the reaction between an aromatic oligoepoxide and guanidine. The second stage was the synthesis of polyetherguanidinium chloride by the reaction between a guanidinium-containing oligoether with terminal guanidine moieties and oligooxyethylenediamine. The bactericidal and fungicidal activity of polyetherguanidinium chloride against various heterotrophic bacteria and microscopic fungi has been shown. It was found that polyetherguanidinium chloride at concentrations of 1–3% inhibited the growth of gram-negative (Escherichia coli 475, Klebsiella pneumonia 479) and gram-positive (Staphylococcus aureus 451) bacteria. The proposed 1% solution of polyetherguanidinium chloride shows a 1.5 times higher antimicrobial activity than the polymeric disinfectant polyhexamethyleneguanidinium chloride for E. coli 475 and K. pneumoniae 479 bacteria and lower antimicrobial activity for S. aureus 451 bacteria. According to the obtained data, it was noted that polyetherguanidinium chloride at a concentration of 1% had a high fungicidal activity against almost all investigated isolates: Aspergillus versicolor F-41250, Acremoneum humicola F-41252, Acremoneum roseum F-41251, Cladosporium sphaerospermum F-41255, Paecilomyces lilacinus F-41256 and Scopulariopsis candida F-41257. Conclusions. Received polyetherguanidinium chloride at a concentration of 1% showed bactericidal activity against S. aureus 451, E. coli 475, K. pneumoniae 479 and fungicidal effect to all fungi studied by us, and so can be used as a disinfectant for building materials.

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