scholarly journals Screening Antimicrobial Activity of Nickel Nanoparticles Synthesized Using Ocimum sanctum Leaf Extract

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Chitra Jeyaraj Pandian ◽  
Rameshthangam Palanivel ◽  
Solairaj Dhanasekaran
Keyword(s):  
Antimicrobial Activity ◽  
Leaf Extract ◽  
Nickel Nanoparticles ◽  
Ocimum Sanctum ◽  
Ros Generation ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Bacteria And Fungi

Antimicrobial efficacy of nickel nanoparticles synthesized using leaf extract of Ocimum sanctum (NiGs) was investigated against pathogenic Gram-negative (E. coli, K. pneumoniae, and S. typhi), Gram-positive (B. subtilis, S. epidermidis) bacteria and fungi (C. albicans, C. tropicalis, A. fumigatus, A. clavatus, and A. niger). 100 µg/mL NiGs showed maximum antimicrobial activity against tested pathogens compared to leaf extract and antibiotics. E. coli (25 mm) and C. albicans (23 mm) exhibited higher zone of inhibition at 100 µg/mL NiGs. MIC, MBC, and MFC values of NiGs against all tested pathogens ranged between 25 and 50 µg/mL. Growth of bacterial and fungal cells (105 cfu/mL) was completely inhibited at 50 µg/mL NiGs. E. coli and C. albicans have showed strong antimicrobial activity with 81% and 50% reactive oxygen species (ROS) production, 30 and 16 µg/mL protein leakage, and 95 and 82 U/L LDH leakages, respectively. Gram-negative bacteria and Candida species showed more sensitivity to NiGs at all concentrations tested (25–100 µg/mL) than Gram-positive bacteria and Aspergillus species, respectively. Microbial growth in the presence of NiGs and ascorbic acid confirmed the involvement of ROS in antimicrobial activity. Hence, NiGs induced ROS generation was attributed to the protein and LDH leakage from microbial membranes.

scholarly journals Antimicrobial Activity and HPLC Fingerprinting of CrudeOcimumExtracts

2011 ◽  
Vol 8 (3) ◽  
pp. 1430-1437 ◽  
Author(s):  
S. S. Deo ◽  
F. Inam ◽  
R. P. Mahashabde
Keyword(s):  
Antimicrobial Activity ◽  
Methanolic Extract ◽  
Ocimum Sanctum ◽  
Moderate Activity ◽  
Aqueous Extracts ◽  
Gram Positive ◽  
Strong Activity ◽  
Gram Negative ◽  
E Coli ◽  
Strong Antimicrobial Activity

The antimicrobial activity of crude methanolic and aqueous extracts ofOcimum sanctumandOcimum kilimandsacharicumagainst gram positive, gram negative and antifungal activity was evaluated to find the zone of inhibition and to set a HPLC profile or fingerprint of these extracts. The crude methanolic extract ofOcimum sanctumshowed strong antimicrobial activity againstS.aureusandC. albicansand moderate activity againstE. coliandB. subtilis. The crude methanolic extract ofOcimum kilimandsacharicumshowed strong antimicrobial activity againstS. aureus, E. coliandC. albicansat higher concentration, same as that shown by the standard forC. albicans. It showed moderate activity againstB. subtilis. The crude aqueous extracts of Ocimum sanctum showed strong antimicrobial activity againstS.aureusand moderate against others. Whereas the crude aqueous extracts ofOcimum kilimandsacharicumshowed moderate activity against the gram positive and gram negative organisms and strong activity againstC. albicansat higher concentration, same as that shown by the standard forC. albicans.

scholarly journals Synthesis and Preliminary Biological Activity Evaluation of New N- Substituted Phthalimide Derivatives

2020 ◽  
Vol 29 (1) ◽  
pp. 247-252
Author(s):  
Halah A. Sahib ◽  
Mohammed H. Mohammed
Keyword(s):  
Antimicrobial Activity ◽  
Methyl Ester ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Ft Ir ◽  
Bacteria And Fungi ◽  
Phenylalanine Methyl Ester

A A new series of bases of Schiff (H2-H4) derived from phthalic anhydrideweresynthesized. These Schiff bases were prepared by the reaction of different amines (tyrosine methyl ester, phenylalanine methyl ester, and isoniazid) with the phthalimide derived aldehyde with the aid of glacial acetic acid or triethylamine ascatalysts. All the synthesized compounds were characterized by (FT-IR and 1HNMR) analyses and were in vitro evaluated for their antimicrobial activity against six various kinds of microorganisms. All the synthesized compounds had been screened for their antimicrobial activity against two Gram-positive bacteria “Staph. Aureus, and Bacillus subtilis”, two Gram-negative bacteria “Escherichia coli, and Klebsiella pneumoniae”, and two fungi species “Candida tropicalis and Candida albicans” using concentrations of 62.5, 125 and 250 µg\mLof derivative in dimethyl sulfoxide(DMSO). All the synthesized compounds showed no activity at all against Gram-positive bacteria, for Gram-negative bacteria and fungi they showed moderate or no activity except compound H1revealedhigh antifungal activityagainstCandida tropicalisat concentrations 125 and 250 µg\ mL. Keywords: Schiff base, phthalic anhydride, antimicrobial.  

Green Synthesis of Silver Nanoparticles from Aqueous Leaf Extract of 'Selaginella bryopteris' and Elucidation of its Antimicrobial Activity

2020 ◽  
Vol 16 (4) ◽  
pp. 449-459
Author(s):  
Varsha Yadav ◽  
Neha Kapoor ◽  
Soma M. Ghorai ◽  
Pradeep
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Aqueous Leaf Extract ◽  
Selaginella Bryopteris

Background: Biosynthesis of nanoparticles from aqueous leaf extract of ‘Selaginella bryopteris’ is a green chemistry approach and is considered to be one of the most efficient methods as it is devoid of toxic chemicals as well as provides natural capping agents for the stabilization of synthesized nanoparticles. ‘S.bryopteris’ also known as ‘Sanjeevani’ (in India), is thought to be prospective natural resource that possesses extraordinary pharmaceutical potential. Objective: S. bryopteris is exclusively native to India and has already been known for its expression of stress-associated genes and high levels of protective metabolites of sugars, phenolic compounds, and polyols. Its potential as an antibacterial agent is being elucidated. Methods: Different leaf extract volumes, silver nitrate (AgNO3) concentrations, and reaction time were investigated separately and the optimal conditions for the synthesis of AgNPs were suggested. The resulting AgNPs were characterized by various techniques like Ultraviolet-Visible (UV-Vis) Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and XRay Diffraction (XRD). Antibacterial assays were carried out by using both agar disk and well diffusion method. Results: The AgNPs synthesized in this process were found to have efficient antimicrobial activity against both Gram-positive as well as Gram-negative bacteria. The antibacterial efficacy of S. bryopteris was consciously tried on uropathogenic Escherichia coli (Gram-negative bacteria) and Bacillus megaterium (Gram-positive bacteria) which have the self-limiting food poisoning potential along with opportunistic uropathogenic bacterial strains namely Proteus mirabilis (Gram-negative bacteria) and a non-pathogenic Micrococcus luteus (Gram-positive bacteria) for comparison. Conclusion: S. bryopteris mediated silver nanoparticles’ synthesis is attempted for being cost-effective, eco-friendly and safe for human therapeutics.

scholarly journals Synthesis and Evaluation of Some Coumarin Based Schiff's Bases as Potential Antimicrobial Agents'

2012 ◽  
Vol 9 (4) ◽  
pp. 2079-2088 ◽  
Author(s):  
Vishakha Bansode ◽  
Meenakshi N. Deodhar
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Agents ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
H Nmr ◽  
Nmr Data ◽  
Bacteria And Fungi

A series of the title compounds 3-(4-(4, 5-dihydro-5-(substituted phenyl)-1H-3-pyrazolyl) phenylimino) methyl)-4-chloro-2H-chromen-2-one 5(a-g) have been synthesized. These compounds were characterized on the basis of their spectral (IR,1H NMR) data and evaluated for antimicrobial activityin vitroagainst gram positive bacteria, gram negative bacteria and fungi. The compound (5b) was found to be the most active with MIC of 20 µg/ml against all the tested organisms.

scholarly journals Muscodor sp. IBRL OS-94, A Promising Endophytic Fungus of Ocimum sanctum with Antimicrobial Activity

2020 ◽  
Vol 27 (2) ◽  
pp. 268-280
Author(s):  
Mohd Taufiq Mat Jalil ◽  
Nabila Husna Hairudin ◽  
Darah Ibrahim
Keyword(s):  
Antimicrobial Activity ◽  
Endophytic Fungus ◽  
Disk Diffusion ◽  
Ocimum Sanctum ◽  
Gram Positive ◽  
Gram Negative ◽  
Fungal Extract ◽  
Gram Positive Bacteria ◽  
Agar Plug ◽  
Diffusion Assay

Background: An endophytic fungus, Muscodor sp. IBRL OS-94 isolated from the leaf of Ocimum sanctum was believed to possess significant antimicrobial activity and several assays were carried out to evaluate its pharmaceutical potential. Methods: Agar plug diffusion and the disk diffusion assays were performed to evaluate the antimicrobial activity of the fungal extract. Also, the broth microdilution assay was done to investigate the minimum inhibitory concentration (MIC) of the fungal extract. Meanwhile, the scanning electron microscope (SEM) was employed to observe the structural degeneration of the microbial cells treated to the extract. Results: The results revealed that fungal isolate showed favorable antimicrobial activity through agar plug diffusion assay and the disk diffusion assay demonstrated that most of the test microorganisms were susceptible to extracellular extract compared to extracellular extract. As for the MIC and MLC values, the extracellular fungal extract exerted a bactericidal/fungicidal effect against all five Gram-positive bacteria, four Gram-negative bacteria, one yeast, and none of the test fungi. Meanwhile, the intracellular fungal extract exhibited bactericidal/fungicidal activity against three Gram-positive bacteria, one Gram-negative bacterium, and one yeast. The structural degeneration study via SEM revealed that various cell abnormalities including severe damage to the cell wall which led to microbial cell death. Conclusion: The present study suggests the fungal extract from Muscodor sp. IBRLOS-94 as an antimicrobial agent.

scholarly journals Enaminone-Derived Pyrazoles with Antimicrobial Activity

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Mashooq Ahmad Bhat ◽  
Mohamed A. Al-Omar ◽  
Ahmed M. Naglah ◽  
Abdul Arif Khan
Keyword(s):  
Antimicrobial Activity ◽  
Gram Negative Bacteria ◽  
Significant Activity ◽  
Disc Diffusion ◽  
Initial Screening ◽  
Gram Positive ◽  
Gram Negative ◽  
Disc Diffusion Assay ◽  
Gram Positive Bacteria ◽  
Diffusion Assay

A series of pyrazoles derived from the substituted enaminones were synthesized and were evaluated for antimicrobial activity. All the compounds were characterized by the spectral data and elemental analysis. The synthesized compounds were initially screened for their antimicrobial activity against ATCC 6538, NCTC 10400, NCTC 10418, and ATCC 27853. During initial screening, compounds (P1, P6, and P11) presented significant antimicrobial activity through disc diffusion assay. These compounds were further evaluated for antimicrobial activity at different time points against Gram-positive and Gram-negative bacteria and presented significant activity for 6 hours. The activity was found to be greater against Gram-positive bacteria. In contrast at 24 hours, the activity was found only against Gram-positive bacteria except compound (P11), showing activity against both types of bacteria. Compound (P11) was found to have highest activity against both Gram-positive and Gram-negative bacteria.

Antimicrobial activity of Pycnarrhena cauliflora (Miers.) Diels. methanol extract

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Eti Nurwening Sholikhah ◽  
Maulina Diah ◽  
Mustofa ◽  
Masriani ◽  
Susi Iravati ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Methanolic Extract ◽  
Biological Activities ◽  
Positive Control ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Methanolic Extracts

Pycnarrhena cauliflora (Miers.) Diels., local name sengkubak, is one of indigenous plants from West Kalimantan that has been used as natural flavor. Pycnorrhena cauliflora is one of species of Menispermaceae family which is rich in bisbenzylisoquinoline alkaloids. This alkaloids are known to have various biological activities including antiprotozoal, antiplasmodial, antifungal and antibacterial activities. This study aimed to investigate antimicrobial activity of  the P. cauliflora (Miers.) Diels. methanolic extracts against gram-positive and gram-negative bacteria. The methanolic extract of P. cauliflora (Miers.) Diels., root, leaf and stem were prepared by maceration. The disk-diffusion method was then used to determine the antimicrobial activity of the extracts against Streptococcus pyogenes, S. mutants, Staphylococcus aureus, S. epidermidis, Salmonella typhi, Shigella flexneri, Pseudomonas aeruginosa and Escherichia coli after 18-24 h incubation at 37 oC. Amoxicillin was used as positive control for gram-positive bacteria and ciprofloxacin was used as gram-negative bacteria. The inhibition zones were then measured in mm. Analysis were conducted in duplicates. The results showed in general the methanolic extracts of P. cauliflora (Miers.) Diels. root (inhibition zone diameter= 10-23 mm) were more active than that leaf (0-15 mm) and stem (0-17 mm) extracts against gram-positive bacteria. The zone inhibition diameter of amoxicillin as positive control was 8-42 mm. In addition, the methanolic extracts of P. cauliflora (Miers.) Diels. root (12-17 mm) were also more active than that leaf (0-12 mm) and stem (0-12 mm) extracts against gram-negative bacteria. The zone inhibition diameter of ciprofloxacin as positive control was 33-36 mm. In conclusion, the methanolic extract of P. caulifloria (Miers.) Diels. root is the most extract active against both gram-positive and gram-negative bacteria. Further study will be focused to isolate active compounds in the methanolic extract of the root.

scholarly journals Construction of Leaderless-Bacteriocin-Producing Bacteriophage Targeting E. coli and Neighboring Gram-Positive Pathogens

2021 ◽  
Author(s):  
Yoshimitsu Masuda ◽  
Shun Kawabata ◽  
Tatsuya Uedoi ◽  
Ken-ichi Honjoh ◽  
Takahisa Miyamoto
Keyword(s):  
Antimicrobial Agents ◽  
Host Strain ◽  
Phage Resistance ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
T7 Phage

We demonstrated that we could combine LLB and phage to construct promising novel antimicrobial agents, LLB-phage. The first LLB-phage, lnqQ -T7 phage, can control the growth of both the Gram-negative host strain and neighboring Gram-positive bacteria while preventing the emergence of phage resistance in the host strain.

ANTIMICROBIAL ACTIVITY OF COPPER KAOLINITE AND SURFACTANT MODIFIED COPPER KAOLINITE AGAINST GRAM POSITIVE AND GRAM NEGATIVE BACTERIA

2016 ◽  
Vol 78 (3-2) ◽  
Author(s):  
Nor Syafawani Sarah Md Saad ◽  
Nik Ahmad Nizam Nik Malek ◽  
Chun Shiong Chong
Keyword(s):  
Antimicrobial Activity ◽  
Synergistic Effects ◽  
Wide Spectrum ◽  
Copper Nitrate ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
X Ray ◽  
Gram Positive Bacteria ◽  
Diffusion Technique

The aim of this research was to determine the antimicrobial activity of kaolinite modified with antimicrobial compounds against Gram positive and Gram negative bacteria. Copper kaolinite (Cu-kaolinite) was prepared by loading raw kaolinite with copper nitrate trihydrate (CuNO3) while surfactant modified Cu-kaolinite (SM-Cu-kaolinite) was prepared by adding cationic surfactants hexadecyltrimethyl ammonium (HDTMA) on Cu-Kaolinite. Samples was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyzer. The antimicrobial activity of the samples was tested against Gram negative bacteria (Escherichia coli ATCC 11229 and Pseudomonas aeruginosa ATCC 15442), and Gram positive bacteria (Staphylococcus aureus ATCC 6538 and Enterococcus faecalis ATCC 29212) through disc diffusion technique (DDT) and minimum inhibition concentration (MIC). The results showed that the antimicrobial activity of Cu-kaolinite increased after modified with HDTMA due to the synergistic effects of Cu ions and HDTMA molecules on the kaolinite. The antimicrobial activity for surfactant modified Cu-kaolinite was greater for Gram positive bacteria compared to Gram negative bacteria. In conclusion, the attachment of HDTMA on Cu-kaolinite contributed to the enhanced antimicrobial activity against wide spectrum of bacteria (Gram positive and Gram negative bacteria).

scholarly journals Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles for antibacterial photodynamic therapy

2019 ◽  
Vol 18 (5) ◽  
pp. 1147-1155 ◽  
Author(s):  
Rehan Khan ◽  
Melis Özkan ◽  
Aisan Khaligh ◽  
Dönüs Tuncel
Keyword(s):  
Antibacterial Activity ◽  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Water Dispersible ◽  
Gram Positive Bacteria ◽  
High Yields

Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles have the ability to generate singlet oxygen in high yields and exhibit light-triggered antibacterial activity against Gram negative bacteria, E. coli as well as Gram positive bacteria, B. subtilis.

Sign in / Sign up

Export Citation Format

Share Document