scholarly journals Tetrabromobisphenol A (TBBPA) exhibits specific antimicrobial activity against Gram-positive bacteria without detectable resistance

2017 ◽  
Vol 53 (25) ◽  
pp. 3512-3515 ◽  
Author(s):  
Fang Ji ◽  
Chang Wang ◽  
Huimin Wang ◽  
Guangliang Liu ◽  
Bolei Chen ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Tetrabromobisphenol A ◽  
Gram Positive ◽  
Gram Positive Bacteria

We report here the antimicrobial ability of tetrabromobisphenol A (TBBPA) against Gram-positive bacteria without detectable resistance.

scholarly journals Antimicrobial Activity of Tetrabromobisphenol A (TBBPA) against Staphylococcus aureus Skin Infections

2018 ◽  
Author(s):  
Chang Wang ◽  
Fang Ji ◽  
Fengjie Chen ◽  
Bolei Chen ◽  
Zhen Zhou ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Wound Closure ◽  
Tetrabromobisphenol A ◽  
Gram Positive ◽  
Inflammatory Infiltration ◽  
Gram Positive Bacteria ◽  
Bactericidal Effects ◽  
Selective Antimicrobial Activity

AbstractTetrabromobisphenol A (TBBPA) is a brominated flame retardant with selective antimicrobial activity against Gram-positive bacteria. We show that TBBPA exerts bactericidal effects by damaging the cell wall and membrane of Staphylococcus aureus (SA) without inducing antimicrobial resistance. In vivo skin infection assays indicate that a low dose of TBBPA could contribute to wound closure and attenuate SA infection and inflammatory infiltration. TBBPA has potential for use as an antimicrobial agent against Gram-positive pathogens.

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 Isopteropodine

2005 ◽  
Vol 60 (5-6) ◽  
pp. 385-388 ◽  
Author(s):  
Rubén García ◽  
Cesia Cayunao ◽  
Ronny Bocic ◽  
Nadine Backhouse ◽  
Carla Delporte ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Gram Positive ◽  
Uncaria Tomentosa ◽  
Gram Positive Bacteria

Bioassay-directed fractionation for the determination of antimicrobial activity of Uncaria tomentosa, has led to the isolation of isopteropodine (0.3%), a known Uncaria pentacyclic oxindol alkaloid that exhibited antibacterial activity against Gram positive 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 PSVII-32 In vitro evaluation of antimicrobial activity of short- and medium-chain fatty acid salts and their combinations against Streptococcus suis

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 465-466
Author(s):  
Cinta Sol ◽  
Mónica Puyalto ◽  
Bernat Canal ◽  
Ana Maria Carvajal ◽  
Manuel Gómez ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Antimicrobial Activity ◽  
Fatty Acid ◽  
Sodium Butyrate ◽  
Chain Fatty Acid ◽  
Medium Chain Fatty Acid ◽  
Gram Positive ◽  
Medium Chain ◽  
Gram Positive Bacteria ◽  
Strong Antimicrobial Activity

Abstract The aim of this study was to investigate the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of organic acid salts against six field isolates of Streptococcus suis. The three products evaluated were sodium salt of coconut fatty acids distillate (DIC) alone and two combinations with sodium butyrate (NaBut): DIC70:30, being 70% of NaBut protected with 30% of DIC; and DIC50:50, being 50% of NaBut protected with 50% of DIC. Antimicrobial susceptibility testing was performed to estimate the MIC values for each product and strain by the broth microdilution method at pH 6.0. MBC values were also determined by sub-culturing supernatant from wells without evident bacterial growth. The values of MIC50/MBC50 were calculated as the concentration which inhibited/killed 50% of the isolates tested. The MIC50 showed DIC as the most effective (8 ppm) against S. suis followed by DIC50:50 (32 ppm) and DIC70:30 (64 ppm). The MBC50 demonstrated a similar trend, DIC being the most effective (16 ppm) followed by DIC50:50 (64 ppm) and DIC70:30 (64 ppm). It is well known that butyric acid is a short-chain fatty acid which has strong antimicrobial activity against Gram-negative bacteria. In contrast, coconut fatty acids distillate is a medium-chain fatty acid source (MCFA) rich in lauric acid which has strong antimicrobial activity against Gram-positive bacteria. Both products are generally available as salts to facilitate their application in feed. In this study, the results showed that DIC was the most effective against the Gram-positive bacteria tested, followed by DIC50:50 and DIC70:30, the sodium butyrate-based products. As expected, a higher concentration of MCFA in the tested product was associated with a higher inhibitory and bactericidal activity. Further studies would be required to better understand these interactions as well as in vivo studies to demonstrate the effects on microbial populations.

scholarly journals Antimicrobial compounds from the Kenyan Ganoderma adspersum (Schulz.) Donk species

2020 ◽  
Vol 13 (7) ◽  
pp. 3390-3397
Author(s):  
Regina Kemunto Mayaka ◽  
Alice Wanjiku Njue ◽  
Moses Kiprotich Langat ◽  
Peter Kiplagat Cheplogoi ◽  
Josiah Ouma Omolo
Keyword(s):  
Antimicrobial Activity ◽  
Ethyl Acetate ◽  
Gram Positive ◽  
Streptococcus Pneumonia ◽  
Antibiotic Resistant ◽  
1H And 13C Nmr ◽  
Gram Positive Bacteria ◽  
Chemical Structures ◽  
Zones Of Inhibition ◽  
Antibacterial And Antifungal

The emergence of antibiotic resistant pathogens has continuously increased, leading to a growing worldwide health threat due to infectious diseases. And therefore in our search for antibacterial and antifungal compounds from the polypore Ganoderma adspersum, the dried, ground fruiting bodies of G. adspersum were extracted with methanol and solvent removed in a rotary evaporator. The extract was suspended in distilled water, then partitioned using ethyl acetate solvent to obtain an ethyl acetate extract. The extract was fractionated and purified using column chromatographic method and further purification on sephadex LH20. The chemical structures were determined on the basis of NMR spectroscopic data from 1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, and NOESY experiments. Antimicrobial activity against clinically important bacterial and fungal strains was assessed and zones of inhibition were recorded. Compound (1), ergosta-7,22-dien-3-one weakly inhibited the growth of Gram positive bacteria Streptococcus pneumonia and a fungus Cryptococcus neoformans. Compounds ergosta-7,22-dien-3-ol (2) and ergosta-5,7,22-trien-3-ol (3) also inhibited gram positive Streptococcus pyogenes bacteria.Keywords: Polypores, steroid compounds, antimicrobial activity.

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 Synthesis and Evaluation of Antimicrobial and Cytotoxic Activity of Oxathiine-Fused Quinone-Thioglucoside Conjugates of Substituted 1,4-Naphthoquinones

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3577
Author(s):  
Yuri E. Sabutski ◽  
Ekaterina S. Menchinskaya ◽  
Ludmila S. Shevchenko ◽  
Ekaterina A. Chingizova ◽  
Artur R. Chingizov ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Cytotoxic Activity ◽  
Antimicrobial Activities ◽  
Biologically Active ◽  
Hydroxyl Group ◽  
Diffusion Method ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
High Cytotoxic Activity ◽  
Derivatives Of

A series of new tetracyclic oxathiine-fused quinone-thioglycoside conjugates based on biologically active 1,4-naphthoquinones and 1-mercapto derivatives of per-O-acetyl d-glucose, d-galactose, d-xylose, and l-arabinose have been synthesized, characterized, and evaluated for their cytotoxic and antimicrobial activities. Six tetracyclic conjugates bearing a hydroxyl group in naphthoquinone core showed high cytotoxic activity with EC50 values in the range of 0.3 to 0.9 μM for various types of cancer and normal cells and no hemolytic activity up to 25 μM. The antimicrobial activity of conjugates was screened against Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus), Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), and fungus Candida albicans by the agar diffusion method. The most effective juglone conjugates with d-xylose or l-arabinose moiety and hydroxyl group at C-7 position of naphthoquinone core at concentration 10 µg/well showed antimicrobial activity comparable with antibiotics vancomicin and gentamicin against Gram-positive bacteria strains. In liquid media, juglone-arabinosidic tetracycles showed highest activity with MIC 6.25 µM. Thus, a positive effect of heterocyclization with mercaptosugars on cytotoxic and antimicrobial activity for group of 1,4-naphthoquinones was shown.

scholarly journals Increases in Hydrophilicity and Charge on the Polar Face of Alyteserin 1c Helix Change its Selectivity towards Gram-Positive Bacteria

Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 238 ◽  
Author(s):  
Yamil Liscano ◽  
Constain H. Salamanca ◽  
Lina Vargas ◽  
Stefania Cantor ◽  
Valentina Laverde-Rojas ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Solid Phase ◽  
Structural Characteristics ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Mutant Derivative ◽  
Conventional Antibiotics ◽  
Carboxy Terminal

Recently, resistance of pathogens towards conventional antibiotics has increased, representing a threat to public health globally. As part of the fight against this, studies on alternative antibiotics such as antimicrobial peptides have been performed, and it has been shown that their sequence and structure are closely related to their antimicrobial activity. Against this background, we here evaluated the antibacterial activity of two peptides developed by solid-phase synthesis, Alyteserin 1c (WT) and its mutant derivative (ΔM), which shows increased net charge and reduced hydrophobicity. These structural characteristics were modified as a result of amino acid substitutions on the polar face of the WT helix. The minimum inhibitory concentration (MIC) of both peptides was obtained in Gram-positive and Gram-negative bacteria. The results showed that the rational substitutions of the amino acids increased the activity in Gram-positive bacteria, especially against Staphylococcus aureus, for which the MIC was one-third of that for the WT analog. In contrast to the case for Gram-positive bacteria, these substitutions decreased activity against Gram-negative bacteria, especially in Escherichia coli, for which the MIC was eight-fold higher than that exhibited by the WT peptide. To understand this, models of the peptide behavior upon interacting with membranes of E. coli and S. aureus created using molecular dynamics were studied and it was determined that the helical stability of the peptide is indispensable for antimicrobial activity. The hydrogen bonds between the His20 of the peptides and the phospholipids of the membranes should modulate the selectivity associated with structural stability at the carboxy-terminal region of the peptides.

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