scholarly journals Antimicrobial assay of endophytic fungi from Rumex madaio and chemical study of strain R1

2019 ◽  
Vol 14 (3) ◽  
pp. 129-135
Author(s):  
Xuelian Bai ◽  
Ronglu Yu ◽  
Mingzhu Li ◽  
Huawei Zhang
Keyword(s):  
Antimicrobial Agents ◽  
Fermentation Broth ◽  
Morphological Characteristics ◽  
Chemical Study ◽  
Human Pathogens ◽  
Inhibitory Effects ◽  
E Coli ◽  
Staphyloccocus Aureus ◽  
Antimicrobial Assay ◽  
Ethyl Acetate Extracts

In order to search more antimicrobial natural products for new drug discovery, bioassay and chemical investigation of endophytic strains from Rumex madaio were carried out. Six fungal strains (numbered as L1, L6, L9, L10, R1, R2) were successfully isolated and their antimicrobial effects on three human pathogens, Escherichia coli, Staphyloccocus aureus and Candida albicans, were evaluated. The results indicated that ethyl acetate extracts of fermentation broth of these strains had no potent antimicorbial activity against E. coli and C. albicans while strains L1 and R1 had stronger inhibitory effects on S. aureus. On basis of morphological characteristics and 18S rRNA sequence analysis, strains L1 and R1 were respectively classified as Colletotrichum and Fusarium geni. The chemical study of strain R1 led to isolation of two known antimicrobial agents, dibutyl phthalate (1) and beauvericin (2).

scholarly journals Isolation and antimicrobial effects of endophytic fungi from Edgeworthia chrysantha

2015 ◽  
Vol 10 (3) ◽  
pp. 529 ◽  
Author(s):  
Huawei Zhang ◽  
Chuanfeng Ruan ◽  
Xuelian Bai
Keyword(s):  
Ethyl Acetate ◽  
Endophytic Fungi ◽  
Fermentation Broth ◽  
Fungal Endophytes ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Antimicrobial Activities ◽  
Human Pathogens ◽  
Antimicrobial Effects ◽  
Staphyloccocus Aureus

<p>Ten fungal strains isolated from <em>Edgeworthia chrysantha</em>, one of traditional medicinal plants in China, were evaluated their antimicrobial activities against three human pathogens, <em>Escherichia coli, Staphyloccocus aureus and Candida albicans</em>, and two phytopathogens, <em>Rhizoctonia cerealis</em> and <em>Colletotrichum gloeosporioides</em>. The results indicated that most ethyl acetate extracts of fermentation broth of these fungal endophytes had stronger antimicrobial activities than their fermentation broth. Among these endophytic strains, both fermentation broth and the ethyl acetate extract of strain D showed the strongest inhibitory effects on all pathogens. Strains 5-19 and BZ also exhibited potent antibacterial activities. However, other strains had weak or no antimicrobial effect. This was the first report on the isolation and antimicrobial effects of endophytic fungi from <em>E. chrysantha</em>.   </p><p> </p>

The contribution of tellurite resistance genes to the fitness of Escherichia coli uropathogenic strains

2007 ◽  
Vol 2 (2) ◽  
pp. 182-191 ◽  
Author(s):  
Danka Valková ◽  
Lenka Valkovičová ◽  
Silvia Vávrová ◽  
Elena Kováčová ◽  
Jozef Mravec ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Resistance Genes ◽  
Antimicrobial Agents ◽  
Uropathogenic Escherichia Coli ◽  
Human Pathogens ◽  
Tellurite Resistance ◽  
Potassium Tellurite ◽  
Coli Isolate ◽  
E Coli

AbstractThe presence of tellurite resistance gene operons has been reported in several human pathogens despite the fact that tellurium, as well as its soluble salts, are both rare in nature and are no longer in use as antimicrobial agents. We have introduced the cloned terWZA-F genes from an uropathogenic Escherichia coli isolate into another clinical E. coli isolate that was shown to be ter-gene free. The presence of the introduced genes increased the level of potassium tellurite resistance, as well as the level of resistance to oxidative stress mediated by hydrogen peroxide; and prolonged the ability of particular strains to survive in macrophages. We therefore propose that the contribution of tellurite resistance genes to oxidative stress resistance in bacteria is at least one reason for their presence in the genomes of a broad range of pathogenic microorganisms.

scholarly journals Preparation of xylitol carbon dots and analysis of its antimicrobial potential in combination with other antimicrobial agents

2019 ◽  
Author(s):  
Vishal Ahuja
Keyword(s):  
Cryptococcus Neoformans ◽  
Carbon Dots ◽  
Antimicrobial Agents ◽  
Salmonella Typhi ◽  
Process Conditions ◽  
Klebsiella Pneumonia ◽  
Human Pathogens ◽  
E Coli ◽  
Ft Ir ◽  
Low Toxicity

Background: Bio-molecule based carbon dots (C-dots) have gained much attention in last few years due to their high biocompatibility, low toxicity and outstanding optical properties which can possibly be used as nano-carrier for drug delivery. Methodology: To find out the best possible conditions for carbon dots preparation from xylitol different combinations of process conditions were evaluated. Synthesized carbon dots were purified and evaluated for their size, surface features, and luminescence by AFM, FT-IR and spectrophoto-fluorometry. Purified C-dots were loaded with conventional antimicrobial compounds and evaluated against clinical isolates of human pathogens. Results: Xylitol and its C-dots were effective against E. coli, S. pyogenes, C. albicans and Cryptococcus neoformans while no activity was recorded against Staphylococcus aureus, Klebsiella pneumonia, Listeria monocytogenes, and Salmonella typhi. In contrast to this conjugates were more effective than conventional antimicrobials. MIC analysis with respect to the four selected pathogens showed that vary small concentration of Am-C dots is sufficient to inhibit the growth of pathogens as 0.01 mg/ml of Am-C dots was sufficient against S. pyogenes but 0.16 mg/ml xylitol and 0.08 mg/ml antimicrobial respectively were required. Similarly 0.16 mg/ml (Escherichia coli), 0.04 mg/ml (Candida albicans & Cryptococcus neoformans) were sufficient which is quite low in terms of concentration in comparison to crude form of antimicrobials and xylitol itself. Conclusion: The results pertaining to current work further suggested that C-dots were not only found more effective but also improved the efficacy of conventional antimicrobials used against the pathogens. Such potential of this important low calorie sweetener can be exploited in variety of healthcare products after further R&D and clinical trials. The efficiency of xylitol C-dots and the conjugates with positive antimicrobials (tetracycline and ketoconazole) against several pathogens also exhibited the useful role of nanotechnology in healthcare.

scholarly journals Antibacterial Activity of the Epidermal Mucus of Barbodes everetti

2018 ◽  
Vol 1 (1) ◽  
pp. a40-44
Author(s):  
JIAZHEN LIM ◽  
YANG LEE ◽  
BADIOZAMAN SULAIMAN ◽  
LESLEY MAURICE BILUNG ◽  
YEE LING CHONG
Keyword(s):  
Antibacterial Activity ◽  
Acetic Acid ◽  
Protein Concentration ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Antimicrobial Properties ◽  
Escherichia Coli O157 ◽  
Human Pathogens ◽  
E Coli ◽  
Epidermal Mucus

The epidermal mucus of fish contains antimicrobial agents that act as biological defence against disease. This study aims to identify antibacterial activity and protein concentration of epidermal mucus of Barbodes everetti, a Bornean endemic freshwater fish. The epidermal mucus was extracted with 3% acetic acid, 0.85% sodium chloride and crude solvents. The mucus activity against eight strains of human pathogenic bacteria, including Bacillus cereus ATCC 33019, Escherichia coli O157:H7, Listeria monocytogenes ATCC 7644, Pseudomonas aeruginosa ATCC 27853, Salmonella braenderup ATCC BAA 664, Salmonella typhimurium, Staphylococcus aureus ATCC 25933, and Vibrio cholerae, were tested. The acetic acid mucus extract of B. everetti was able to inhibit five strains of bacteria and show no activity toward E. coli O157:H7, B. cereus ATCC 33019 and L. monocytogenes ATCC 7644. Moreover, the highest protein concentration was quantified in crude extract, followed by aqueous and acetic acid extracts. This study provides a preliminary knowledge on the activity of epidermal mucus of B. everetti towards five out of the eight human pathogens tested, therefore it may contain potential sources of novel antibacterial components which could be further extracted for the production of natural antibiotics towards human-related pathogenic bacteria. Keywords: Antibacterial, antimicrobial properties, Barbodes everetti, epidermal mucus, pathogenic bacteria

Synthesis of Novel Azetidinyl-3-(isonicotinamide-yl)-6-iodoquinazolin- 4-ones as Antimicrobial and Antitubercular Agents

2012 ◽  
Vol 5 (2) ◽  
pp. 1735-1744
Author(s):  
Jignesh Priyakant Raval ◽  
Akhaja T N ◽  
Myangar K N ◽  
D R Naik
Keyword(s):  
Mass Spectrometry ◽  
Antibacterial Activity ◽  
Spectral Analysis ◽  
Biological Activity ◽  
Antimicrobial Agents ◽  
Antitubercular Agents ◽  
Human Pathogens ◽  
E Coli ◽  
Mycobacterium Tuberculosis H37rv

A novel new series of 2-[(4'-oxo-3'-chloro-2'-phenylazetidin-1'-yl)-aminomethyl]-3-[N-isonicotinamide-yl]-6-iodo-quinazolin-4-ones were synthesized using the reaction of chloroacetylchloride and appropriate Schiff base. The synthesized compounds were characterized on the basis of their elemental and spectral analysis (IR, 1H-NMR, 13C-NMR and mass spectrometry). All newly synthesized compounds were evaluated for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv. They were also tested in vitro for antibacterial activity against selected human pathogens such as E. coli, P. aeruginosa, K. pneumoniae, S. typhi, S. aureus, S. pyogenus, B. subtilis and antifungal activity against C. albicans, A. niger, A. clavatus strains. The selected 6-iodo-quinazolinonones showed promising biological activity and could be useful as antimicrobial agents.   

SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF 3-FORMYL INDOLE BASED SCHIFF BASES

2018 ◽  
Vol 7 (6) ◽  
Author(s):  
Singh Gurvinder ◽  
Singh Prabhsimran ◽  
Dhawan R. K.
Keyword(s):  
Antimicrobial Activity ◽  
Spectral Analysis ◽  
Schiff Bases ◽  
Antimicrobial Agents ◽  
Biological Evaluation ◽  
Fungal Strain ◽  
Bacterial Strains ◽  
Standard Drug ◽  
Gram Negative ◽  
E Coli

In order to develop new antimicrobial agents, a series of 3-formyl indole based Schiff bases were synthesized by reacting 3-formyl indole(indole-3-carboxaldehyde) with substituted aniline taking ethanol as solvent. The reaction was carried in the presence of small amount of p-toluene sulphonic acid as catalyst.All the synthesized compounds were characterized by IR, 1H-NMR spectral analysis. All the synthesized compounds were evaluated for antimicrobial activity against two gram positive bacterial strains (B. subtilisand S. aureus) and two gram negative bacterial strains (P. aeruginosaand E. coli) and one fungal strain (C. albicans). All the synthesized compounds were found to have moderate to good antimicrobial activity. The  standard drug amoxicillin, fluconazole were used for antimicrobial activity. Among the synthesized compounds, the maximum antimicrobial activity was shown by compounds GS04, GS07, GS08 and GS10.

Efficacy of Silver Nanoparticles Synthesized from Hymenocallis species (Spider Lilly) Leaf Extract as Antimicrobial Agents

2019 ◽  
Vol 12 (5) ◽  
pp. 4644-4647
Author(s):  
K.K. Gupta ◽  
Neha Kumari ◽  
Neha Sinha ◽  
Akruti Gupta
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Antimicrobial Agents ◽  
Color Change ◽  
Bacterial Species ◽  
Antimicrobial Property ◽  
Biogenic Synthesis ◽  
E Coli ◽  
Light Yellow ◽  
Antibiotic Property

Biogenic synthesis of silver nanoparticles synthesized from Hymenocallis species (Spider Lilly) leaf extract was subjected for investigation of its antimicrobial property against four bacterial species (E. coli, Salmonella sp., Streptococcus sp. & Staphylococcus sp.). The results revealed that synthesized nanoparticles solution very much justify the color change property from initial light yellow to final reddish brown during the synthesis producing a characteristics absorption peak in the range of 434-466 nm. As antimicrobial agents, their efficacy was evaluated by analysis of variance in between the species and among the different concentration of AgNPs solution, which clearly showed that there was significant variation in the antibiotic property between the four different concentrations of AgNPs solution and also among four different species of bacteria taken under studies. However, silver nanoparticles solution of 1: 9 and 1:4 were proved comparatively more efficient as antimicrobial agents against four species of bacteria.

Antimicrobial Effects of Zataria multiflora and Ocimum basilicum on Escherichia coli O157:H7 During Ripening of Traditional Lighvan Cheese

2020 ◽  
Vol 16 (3) ◽  
pp. 373-380
Author(s):  
Mohammad B. Zendeh ◽  
Vadood Razavilar ◽  
Hamid Mirzaei ◽  
Khosrow Mohammadi
Keyword(s):  
Escherichia Coli ◽  
Essential Oils ◽  
Dairy Products ◽  
Antimicrobial Agents ◽  
Escherichia Coli O157 ◽  
Zataria Multiflora ◽  
Antimicrobial Effects ◽  
E Coli ◽  
Common Causes ◽  
Lighvan Cheese

Background: Escherichia coli O157:H7 is one of the most common causes of contamination in Lighvan cheese processing. Using from natural antimicrobial essential oils is applied method to decrease the rate of microbial contamination of dairy products. The present investigation was done to study the antimicrobial effects of Z. multiflora and O. basilicum essential oils on survival of E. coli O157:H7 during ripening of traditional Lighvan cheese. Methods: Leaves of the Z. multiflora and O. basilicum plants were subjected to the Clevenger apparatus. Concentrations of 0, 100 and 200 ppm of the Z. multiflora and 0, 50 and 100 ppm of O. basilicum essential oils and also 103 and 105 cfu/ml numbers of E. coli O157:H7 were used. The numbers of the E. coli O157:H7 bacteria were analyzed during the days 0, 30, 60 and 90 of the ripening period. Results: Z. multiflora and O. basilicum essential oils had considerable antimicrobial effects against E. coli O157:H7. Using the essential oils caused decrease in the numbers of E. coli O157:H7 bacteria in 90th days of ripening (P <0.05). Using from Z. multiflora at concentration of 200 ppm can reduce the survival of E. coli O157:H7 in Lighvan cheese. Conclusion: Using Z. multiflora and O. basilicum essential oils as good antimicrobial agents can reduce the risk of foodborne bacteria and especially E. coli O157:H7 in food products.

Design of Arylsulfonylhydrazones as Potential FabH Inhibitors: Synthesis, Antimicrobial Evaluation and Molecular Docking

2019 ◽  
Vol 15 ◽  
Author(s):  
Thais Batista Fernandes ◽  
Natanael Dante Segretti ◽  
Felipe Rebello Lourenço ◽  
Thalita Marcílio Cândido ◽  
André Rolim Baby ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Molecular Docking ◽  
Antimicrobial Agents ◽  
Acyl Carrier Protein ◽  
Condensation Reaction ◽  
Lung Fibroblast ◽  
Fibroblast Cells ◽  
Human Lung Fibroblast ◽  
Persistent Problem ◽  
E Coli

Background: Antimicrobial resistance is a persistent problem about infections treatment and carries needing for develop new antimicrobial agents. Inhibiting of bacterial β-ketoacyl acyl carrier protein synthase III (FabH), which catalyzes the condensation reaction between a CoA-attached acetyl group and an ACP-attached malonyl group in bacteria is an interesting strategy to find new antibacterial agents. Objective: The aim of this work was to design and synthesize arylsulfonylhydrazones potentially FabH inhibitors and evaluate their antimicrobial activity. Methods: MIC50 of sulfonylhydrazones against E. coli and S. aureus was determined. Antioxidant activity was evaluated by DPPH (1-1’-diphenyl-2-picrylhydrazyl) assay and cytotoxicity against LL24 lung fibroblast cells was verified by MTT method. Principal component analysis (PCA) was performed in order to suggest a structure-activity relationship. Molecular docking allowed to propose sulfonylhydrazones interactions with FabH. Results: The most active compound showed activity against S. aureus and E. coli, with MIC50 = 0.21 and 0.44 µM, respectively. PCA studies correlated better activity to lipophilicity and molecular docking indicated that sulfonylhydrazone moiety is important to hydrogen-bond with FabH while methylcatechol ring performs π-π stacking interaction. The DPPH assay revealed that some sulfonylhydrazones derived from the methylcatechol series had antioxidant activity. None of the evaluated compounds was cytotoxic to human lung fibroblast cells, suggesting that the compounds might be considered safe at the tested concentration. Conclusion: Arylsufonylhydrazones is a promising scaffold to be explored for design of new antimicrobial agents.

scholarly journals Facile Use of ZnO Nanopowders to Protect Old Manual Paper Documents

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5452
Author(s):  
Ludmila Motelica ◽  
Aurelian Popescu ◽  
Anca-Gabriela Răzvan ◽  
Ovidiu Oprea ◽  
Roxana-Doina Truşcă ◽  
...  
Keyword(s):  
Hand Hygiene ◽  
Antimicrobial Agents ◽  
Storage Conditions ◽  
Human Pathogens ◽  
Accessible Method

One of the main problems faced by libraries, archives and collectors is the mold degradation of the paper-based documents, books, artworks etc. Microfungi (molds) emerge in regular storage conditions of such items (humidity, usually over 50%, and temperatures under 21 °C). If the removal of the visible mycelium is relatively easy, there is always the problem of the subsequent appearance of mold as the spores remain trapped in the cellulosic, fibrillary texture, which acts as a net. Moreover, due to improper hand hygiene bacteria contamination, old books could represent a source of biohazard, being colonized with human pathogens. An easy and accessible method of decontamination, which could offer long term protection is therefore needed. Here, we present a facile use of the ZnO nanopowders as antimicrobial agents, suitable for cellulose-based products, conferring an extended antibacterial and anti-microfungal effect. The proposed method does not adversely impact on the quality of the cellulose documents and could be efficiently used for biodegradation protection.

Sign in / Sign up

Export Citation Format

Share Document