scholarly journals Antibacterial Potential of Aloe weloensis (Aloeacea) Leaf Latex against Gram-Positive and Gram-Negative Bacteria Strains

2019 ◽  
Vol 2019 ◽  
pp. 1-4
Author(s):  
Yohannes Kelifa Emiru ◽  
Ebrahim Abdela Siraj ◽  
Tekleab Teka Teklehaimanot ◽  
Gedefaw Getnet Amare
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Maximum Activity ◽  
New Drugs ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative

Objective. To evaluate the antibacterial effects of the leaf latex of Aloe weloensis against infectious bacterial strains. Methods. The leaf latex of A. weloensis at different concentrations (400, 500, and 600 mg/ml) was evaluated for antibacterial activities using the disc diffusion method against some Gram-negative species such as Escherichia coli (ATCC 14700) and Pseudomonas aeruginosa (ATCC 35619) and Gram-positive such as Staphylococcus aureus (ATCC 50080) and Enterococcus fecalis (ATCC 4623). Results. The tested concentrations of the latex ranging between 400 and 600 mg·mL−1 showed significant antibacterial activity against bacterial strain. The highest dose (600 mg/ml) of A. weloensis leaf latex revealed the maximum activity (25.93 ± 0.066 inhibition zone) followed by the dose 500 mg/ml against S. aureus. The lowest antibacterial activity was observed by the concentration 400 mg/ml (5.03 ± 0.03) against E. coli. Conclusion. The results of the present investigation suggest that the leaf latex of A. weloensis can be used as potential leads to discover new drugs to control some bacterial infections.

scholarly journals Evaluation of antibacterial activity of vitamin C against human bacterial pathogens

2023 ◽  
Vol 83 ◽  
Author(s):  
S. Mumtaz ◽  
S. Mumtaz ◽  
S. Ali ◽  
H. M. Tahir ◽  
S. A. R. Kazmi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Vitamin C ◽  
Bacterial Infections ◽  
Unmet Need ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Adjunct Treatment

Abstract Now a day’s multidrug resistance phenomenon has become the main cause for concern and there has been an inadequate achievement in the development of novel antibiotics to treat the bacterial infections. Therefore, there is an unmet need to search for novel adjuvant. Vitamin C is one such promising adjuvant. The present study was aimed to elucidate the antibacterial effect of vitamin C at various temperatures (4°C, 37°C and 50°C) and pH (3, 8, and 11), against Gram-positive and Gram-negative bacteria at various concentrations (5-20 mg/ml) through agar well diffusion method. Growth inhibition of all bacterial strains by vitamin C was concentration-dependent. Vitamin C significantly inhibited the growth of Gram-positive bacteria: Bacillus licheniformis (25.3 ± 0.9 mm), Staphylococcus aureus (22.0 ± 0.6 mm), Bacillus subtilis (19.3 ± 0.3 mm) and Gram-negative bacteria: Proteus mirabilis (27.67 ± 0.882 mm), Klebsiella pneumoniae (21.33±0.9 mm), Pseudomonas aeruginosa (18.0 ± 1.5 mm) and Escherichia coli (18.3 ± 0.3 mm). The stability of vitamin C was observed at various pH values and various temperatures. Vitamin C showed significant antibacterial activity at acidic pH against all bacterial strains. Vitamin C remained the stable at different temperatures. It was concluded that vitamin C is an effective and safe antibacterial agent that can be used in the future as an adjunct treatment option to combat infections in humans.

Antibacterial Activity of Amine-Functionalized Zeolite NaY against Staphylococcus aureus ATCC6538 and Escherichia coli ATCC11229

2015 ◽  
Vol 761 ◽  
pp. 402-406 ◽  
Author(s):  
Siti Aishah Mohd Hanim ◽  
Nik Ahmad Nizam Nik Malek ◽  
Zaharah Ibrahim ◽  
Mashitah Mad Salim ◽  
Nur Isti'anah Ramli ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Gram Positive ◽  
Gram Negative ◽  
Zeolite Nay ◽  
Amine Functionalized ◽  
Diffusion Technique

The antibacterial activity of functionalized zeolite NaY (CBV100) with different concentrations of 3-aminopropyltriethoxysilane (APTES) (0.01, 0.05, 0.20 and 0.40 M) was studied against Staphylococcus aureus ATCC 6538 (Gram positive) and Escherichia coli ATCC 11229 (Gram negative) through disc diffusion technique (DDT). The characterization of functionalized zeolite NaY with fourier transform infrared (FTIR) spectroscopy indicated the attachment of APTES on zeolite NaY. Through DDT, the inhibition zone of functionalized zeolite NaY increased proportionally to the amount of the amine-functional group attached onto zeolite NaY. Functionalized zeolite NaY showed higher antibacterial activity against Gram-positive compared to Gram-negative bacteria. It can be concluded from this study that amine-functionalized zeolite NaY shows evidence of antibacterial activities.

scholarly journals Antibacterial Activities of Xanthium Strumarium L.

2018 ◽  
Vol 29 ◽  
pp. 70-77 ◽  
Author(s):  
Anjana Devkota ◽  
Ritu Kumari Das
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Antibacterial Activities ◽  
Diffusion Method ◽  
Xanthium Strumarium ◽  
Distilled Water ◽  
Leaf Extracts ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Antibacterial activities of Xanthium strumarium L. (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. The antibacterial activity was studied against six pathogenic bacteria, three gram negative: Klebsiella pneumoniae (ATCC 15380), Proteus mirabilis (ATCC 49132), Escherichia coli (ATCC 25922) and three gram positive: Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25932) at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ ml, 250 mg/ml) of leaf extracts of X. strumurium. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antibacterial activity of extracts was determined by disc diffusion method and zone of inhibition (ZOI) was measured. Gram negative bacteria was found more resistant than gram positive bacteria. The most susceptible bacterium was S. aureus while the most resistant bacterium was E. coli. Methanolic extract was found more effective than distilled water. These findings suggest that extracts obtained from leaves of X. strumurium possess biobactericidal potential, which can suitably be exploited for making antibacterial drugs.J. Nat. Hist. Mus. Vol. 29, 2015, Page: 70-77

scholarly journals The Antibacterial Activity of Catunaregam tomentosa Against Selected Gram-Positive and Gram-Negative Bacteria

2021 ◽  
Vol 5 (S1) ◽  
pp. 34-38
Author(s):  
Nor Aleesa Ali ◽  
Wan Amalina Wan Mamat ◽  
Syed Ahmad Tajudin Tuan Johari ◽  
Muhammad Yusran Abdul Aziz ◽  
Ahmad Syibli Othman
Keyword(s):  
Antibacterial Activity ◽  
Plant Extracts ◽  
Bacterial Infections ◽  
Scientific Basis ◽  
Diffusion Method ◽  
Antibacterial Drug ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Value Evaluation

Catunaregam tomentosa is a plant from Rubiaceae family that is used in traditional medicine for the treatment of stomatitis and ulcers due to bacterial infections. Besides, it also helps in the treatment of oliguria and dysuria. Indiscriminate use of commercial antibacterial medicines had led to the search for novel antibacterial drugs. Since for ages medicinal plants have been used to treat bacterial infection, so they can be excellent sources of the novel antibacterial drug. To evaluate the scientific basis of the use of plant, antibacterial activity leaves extract of C.tomentosa was investigated against selected Gram-positive and Gram-negative bacteria. The study also investigated the effect of pH on its antibacterial activity. Antibacterial activity of the plant extracts was evaluated against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa by using the disc diffusion method at 100mg/mL concentration. Extracts of C. tomentosa inhibit the activity of S. aureus but do not inhibit the activity of Gram-negative bacteria. Minimum inhibitory concentration (MIC) was also determined against S. aureus at concentration 100, 50, 25, 12.5, 6, 3, 1.5, 0.75 and 0.395mg/mL and 3mg/mL were the MIC value. Evaluation on the effect of different pH on antibacterial activity of plant extracts shows that the activity of the plant extracts does not affect when treated with acidic pH but increased at alkaline pH. Based on the present finding, C. tomentosa leaves extract have the potential to be a viable candidate in the discovery of a natural antibacterial agent against S. aureus infections. This study provides scientific knowledge to further determine the antibacterial values of C. tomentosa extracts.

scholarly journals Molecular Computation and Antibacterial Activity of Cu (II) Complex of Naphthaldehyde Thiosemicarbazone

2020 ◽  
pp. 85-93
Keyword(s):  
Antibacterial Activity ◽  
Molecular Geometry ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Spectral Measurements ◽  
Gram Positive ◽  
Activity Data ◽  
Gram Negative ◽  
Diffusion Technique ◽  
Parent Ligand

Copper (II) complex of naphthaldehyde thiosemicarbazone (L) has been synthesized and characterized by melting points, conductance, magnetic, infrared, and ESI-MS spectral measurements in addition to elemental analysis. A tetrahedral structure is suggested for the complex. The antibacterial activities of the complex and ligand were evaluated by the disc diffusion technique. Pure bacteria cultures of Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) were used to check the antibacterial activities of the synthesized compounds. Antibacterial activities were compared by measuring the inhibition zone diameter and chloramphenicol was used as a reference. Both the compounds showed significant antibacterial activity in different range against gram-positive & gram-negative bacteria. The antibacterial activity data also show that the Cu(II) complex to be more effective than the parent ligand. Molecular geometry of the complex has been optimized by ChemDraw Ultra 12.0 and then MM2 calculation has been done.

scholarly journals Antibacterial activity of Beta vulgaris L. pomace extract

2011 ◽  
pp. 263-269 ◽  
Author(s):  
Aleksandra Velicanski ◽  
Dragoljub Cvetkovic ◽  
Sinisa Markov ◽  
Jelena Vulic ◽  
Sonja Djilas
Keyword(s):  
Antibacterial Activity ◽  
Beta Vulgaris ◽  
Staphylococcus Epidermidis ◽  
Control Sample ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Natural Isolates

Antibacterial activity of Beta vulgaris L. (beetroot) pomace extract (concentration 100 mg/ml) was tested against five Gram positive and seven Gram negative bacterial strains (reference cultures and natural isolates). Disc diffusion method with 15 ?l of extract and agar-well diffusion method with 50 and 100 ?l were used. Antibiotic (cefotaxime/clavulanic acid) was used as a control sample. The tested extract showed the highest activity against Staphylococcus aureus and Bacillus cereus, where clear zones (without growth) appeared. There was no any activity against other tested Gram-positive bacteria, except for Staphylococcus epidermidis, with a small zone of reduced growth. Growth of all tested Gram-negative bacteria was inhibited usually with 100 ?l of extract. The most susceptible were Citrobacter freundii and Salmonella typhymurium. The tested antibiotic gave clear, usually large zones for all tested strains except for Staphylococcus cohni spp. cohni, where only a zone of reduced growth appeared.

scholarly journals Antibacterial properties of an Indian traditional medicinal plant, Rhynchosia scarabaeoides (L.) DC. (Fabaceae)

2011 ◽  
Vol 1 (1) ◽  
pp. 17 ◽  
Author(s):  
Surekha Challa ◽  
Kiran K. Rajam ◽  
Vishnu V. V. Satyanarayana Kasapu ◽  
Suresh Kumar Tanneeru ◽  
Venkata Siva Satyanarayana Kantamreddi
Keyword(s):  
Ethyl Acetate ◽  
Bacterial Infections ◽  
Antibacterial Properties ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Traditional Healers ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Plant Parts ◽  
Ethanol Extracts

<em>Rhynchosia scarabaeoides </em>(L.) DC plant parts are extensively used by traditional healers in India to treat a variety of bacterial diseases, such as dysentery, diarrohea and skin disorders. This article reports the antibacterial activities of n-hexane, ethyl acetate and ethanol extracts belonging to the leaf, stem and root parts of <em>R. scarabaeoides</em> against five bacterial strains, <em>Bacillus subtilis</em>, <em>Escherichia coli</em>, <em>Klebseilla pneumonia</em>, <em>Proteus vulgaris</em> and <em>Staphylococcus aureus</em>, using an agar gel diffusion method. The range of inhibition zone (IZ) was found to be 15-24 mm and the minimum inhibitory activity (MIC) was found to be 1 mL/well. The IZ was found to be higher in ethyl acetate extracts while this was moderate in ethanol extracts, and no activity was seen with n-hexane extracts or root extracts. The MIC value of leaf ethyl acetate extract was found to be 1 mg against bacterial strains <em>P. vulgaris</em> and <em>S. aureus</em>, whereas 2 mg was found against <em>B. subtilis</em>, <em>K. pneumoniae</em> and <em>E. coli</em>. These results support the traditional usage of R. scarabaeoides plant parts in the treatment of bacterial infections. Interestingly, this plant was screened for antibacterial activity for the first time and was found to be active. Detailed chemical investigations are, therefore, warranted.

In vitro Antibacterial Activity of 7-Substituted-6-Fluoroquinolone and 7-Substituted-6,8-Difluoroquinolone Derivatives

Chemotherapy ◽  
2017 ◽  
Vol 62 (3) ◽  
pp. 194-198 ◽  
Author(s):  
Socorro Leyva-Ramos ◽  
Denisse de Loera ◽  
Jaime Cardoso-Ortiz
Keyword(s):  
Antibacterial Activity ◽  
Antimicrobial Agents ◽  
New Drugs ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative

Background: Fluoroquinolones are widely prescribed synthetic antimicrobial agents. Quinolones act by converting their targets, gyrase and topoisomerase IV, into toxic enzymes that fragment the bacterial chromosome; the irreversible DNA damage eventually causes the killing of bacteria. Thorough knowledge of the structure-activity relationship of quinolones is essential for the development of new drugs with improved activity against resistant strains. Methods: The compounds were screened for their antibacterial activity against 4 representing strains using the Kirby-Bauer disk diffusion method. Minimal inhibitory concentration (MIC) was determined by measuring the diameter of the inhibition zone using concentrations between 250 and 0.004 μg/mL. Results: MIC of derivatives 2, 3, and 4 showed potent antimicrobial activity against gram-positive and gram-negative bacteria. The effective concentrations were 0.860 μg/mL or lower. MIC for compounds 5-11 were between 120 and 515 μg/mL against Escherichia coli and Staphylococcus aureus, and substituted hydrazinoquinolones 7-10 showed poor antibacterial activity against gram-positive and gram-negative bacteria compared with other quinolones. Conclusion: Compounds obtained by modifications on C-7 of norfloxacin with the acetylated piperazinyl, halogen atoms, and substituted hydrazinyl showed good in vitro activity - some even better than the original compound.

scholarly journals Antibacterial Activity of Floral Petals of Some Angiosperms

2019 ◽  
pp. 1-5 ◽  
Author(s):  
L. Rajanna ◽  
N. Santhosh Kumar ◽  
N. S. Suresha ◽  
S. Lavanya
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Inhibition Zone ◽  
Bacterial Strains ◽  
Inhibitory Zone ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Antibacterial Assay

The in vitro antibacterial assay was carried out against both Gram positive (B. cerus and S. aureus) and Gram negative (E. coli and K. pneumoniae) bacteria. Floral petals of 20 different species of plants were collected and tested for antibacterial activity. The result showed that the petals were active against both Gram positive and Gram negative. Out of 20 floral petals tested, 19 floral petals exhibited antibacterial activity against selected bacterial strains. The minimal inhibitory zone of floral petal discs against human pathogenic bacteria varies from 2 – 6 mm. Rosa carolina and Ruellia tuberosa showed significance inhibition zone for all the bacterial strains while Lantana camara does not show inhibition zone for any of these pathogenic bacteria.

scholarly journals The spectrum of antibacterial activity of human defensins and cathelicidin against gram-positive and gram-negative bacterial strains isolated from hospitalized patients

2020 ◽  
Author(s):  
Albert Bolatchiev
Keyword(s):  
Antibacterial Activity ◽  
Synergistic Effect ◽  
Hospitalized Patients ◽  
New Drugs ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Conventional Antibiotics ◽  
Human Defensins

AbstractBackgroundTo date, there is a spread of resistance of microorganisms to antibiotics. To solve this problem, the search and development of new drugs with antibacterial activity is necessary. Antimicrobial peptides (AMPs) have pronounced antibacterial activity and may be promising candidates for the role of new drugs. Besides, AMPs can be used to overcome conventional antibiotics resistance due to the possible synergistic effect. In this work, the combined effect of some AMPs (human defensins, HNP-1, hBD-1, hBD-3 and cathelicidin, LL-37) with conventional antibiotics (vancomycin and imipenem) against gram-positive (Enterococcus faecalis; Staphylococcus aureus, methicillin-sensitive, MSSA, and methicillin-resistant, MRSA) and gram-negative (Escherichia coli; Klebsiella pneumoniae; Pseudomonas aeruginosa) bacterial strains was investigated.MethodsBacterial strains were isolated from hospitalized patients of the intensive care unit. Commercially available AMPs (HNP-1, hBD-1, hBD-3, LL-37 by Cloud-Clone Corp., USA) and antibiotics, vancomycin (Sandoz, Slovenia) and imipenem (Merck Sharp and Dohme, USA) were used. Antibiotic resistance phenotypes of isolated bacterial strains were carried out using the disk diffusion method. The standard checkerboard assays were used to study minimum inhibitory concentrations (MIC) of antimicrobials. The combined microbicidal effect of two substances (AMP+conventional antibiotic) was assessed by the fractional inhibitory concentration index (FICI). If FICI ≤ 0,5, then it was considered that two substances showed synergism of action; if 0.5 < FICI < 4 – no interaction; if FICI > 4 – antagonism.ResultsAll studied AMPs had antibacterial activity against the studied strains. hBD-3 showed the lowest MICs compared to other AMPs. MIC of hBD-3 against S. aureus (MSSA and MRSA), E. coli, K. pneumoniae was the same – 0.5 mg/L, and against P. aeruginosa it was 2 mg/L. The combinations HNP-1+vancomycin (against E. faecalis) and hBD-3+imipenem (against E. coli, K. pneumoniae, P. aeruginosa) according to FICI values have shown the synergistic effect. The results of this study can be used to develop novel antibiotics based on AMPs. Also, in some cases, AMPs can help to overcome resistance to conventional antibiotics.

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