scholarly journals Biofilm Inhibition and Antimicrobial Properties of Silver-Ion-Exchanged Zeolite A against Vibrio spp Marine Pathogens

2021 ◽  
Vol 11 (12) ◽  
pp. 5496
Author(s):  
Zarina Amin ◽  
Nur Ariffah Waly ◽  
Sazmal Effendi Arshad

A challenging problem in the aquaculture industry is bacterial disease outbreaks, which result in the global reduction in fish supply and foodborne outbreaks. Biofilms in marine pathogens protect against antimicrobial treatment and host immune defense. Zeolites are minerals of volcanic origin made from crystalline aluminosilicates, which are useful in agriculture and in environmental management. In this study, silver-ion-exchanged zeolite A of four concentrations; 0.25 M (AgZ1), 0.50 M (AgZ2), 1.00 M (AgZ3) and 1.50 M (AgZ4) were investigated for biofilm inhibition and antimicrobial properties against two predominant marine pathogens, V. campbelli and V. parahemolyticus, by employing the minimum inhibitory concentration (MIC) and crystal violet biofilm quantification assays as well as scanning electron microscopy. In the first instance, all zeolite samples AgZ1–AgZ4 showed antimicrobial activity for both pathogens. For V. campbellii, AgZ4 exhibited the highest MIC at 125.00 µg/mL, while for V. parahaemolyticus, the highest MIC was observed for AgZ3 at 62.50 µg/mL. At sublethal concentration, biofilm inhibition of V. campbelli and V. parahemolyticus by AgZ4 was observed at 60.2 and 77.3% inhibition, respectively. Scanning electron microscopy exhibited profound structural alteration of the biofilm matrix by AgZ4. This is the first known study that highlights the potential application of ion-exchanged zeolite A against marine pathogens and their biofilms.

Author(s):  
Zarina Amin ◽  
SAZMAL EFFENDI ARSHAD ◽  
NUR ARIFAH WALY

A challenging problem in the aquaculture industry is bacterial disease outbreaks which results in the global reduction of fish supply and foodborne outbreaks. Biofilms in marine pathogens protect against antimicrobial treatment and host immune defence. Zeolites are minerals of volcanic origin made from crystalline aluminosilicates which are useful in agriculture and in environmental management. In this study, silver ion-exchanged zeolite A of four concentrations; 0.25M (AgZ1), 0.50M (AgZ2), 1.00M (AgZ3)and 1.50M (AgZ4) were investigated for biofilm inhibition and antimicrobial properties against two predominant marine pathogens V. campbelli and V. parahemolyticus by employing the Minimum Inhibitory Concentration(MIC), Crystal Violet Biofilm Quantification assays as well as Scanning Electron Microscopy. In the first instance, all zeolite samples AgZ1-AgZ4 showed antimicrobial activity for both pathogens. For V. campbellii AgZ4 exhibited the highest MIC at 125.00 µg/ml while for V. parahaemolyticus the highest MIC was observed for AgZ3 at 62.50 µg/ml. At sublethal concentration, biofilm inhibition of V. campbelli and V. parahemolyticus by AgZ4 were observed at 60.2% and 77.3% inhibition respectively. Scanning electron microscopy exhibited profound structural alteration of the biofilm matrix by AgZ4. This is the first known study that highlights the potential application of ion-exchanged Zeolite A against marine pathogens and their biofilms.


Author(s):  
Mohd. Ghazali Mohd. Nawawi ◽  
Le T. Ngoc Tram

Kajian pervaporasi (PV) penyahidratan isopropanol (IPA) menggunakan membran kitosan terubahsuai telah dijalankan. Membran disediakan daripada kitosan dan diubahsuai menggunakan zeolite–A. Zeolit–A yang diketahui beratnya ditambahkan ke dalam pelarut berasid dan diaduk untuk menghasilkan larutan homogen. Kepingan kitosan kemudian ditambahkan ke dalam larutan tersebut dan diaduk semalaman. Pelbagai nisbah zeolit–A dan kitosan daripada 1:20 hingga 1:2 digunakan untuk menghasilkan membran kitosan terubahsuai. Larutan kitosan–zeolit–A dituangkan ke atas plat kaca dan dikeringkan pada suhu bilik. Membran yang dikeringkan kemudian dirawat dengan larutan alkali dan dibasuh di dalam air ternyahion. Sifat hidrofilik membran dikaji melalui ujian pengembungan. Ujian dijalankan dalam campuran 90 wt.% IPA–air. Keputusan menunjukkan bahawa darjah pengembungan berkurangan dengan penambahan zeolit–A. Sifat mekanikal membran dikaji untuk kekuatan tegangan dan pemanjangan pada takat putus. Kemudian, membran tersebut dikaji untuk pemisahan campuran IPA–air pada tekanan 720 mmHg di bawah vakum. Kepekatan suapan diubah daripada 0 hinga 95 wt.% IPA dan suhu suapan diubah daripada 30 hingga 70°C. Keputusan menunjukkan bahawa nisbah 1:8 antara zeolit dan kitosan menghasilkan kombinasi terbaik untuk mengubahsuai membran bagi pemisahan campuran IPA–air. Struktur morfologi membran kitosan–zeolit–A dengan nisbah 1:8 dan 1:2 berat zeolit–A/berat kiotsan dikaji menggunakan Scanning Electron Microscopy (SEM). Keputusan menunjukkan bahawa membran yang dihasilkan adalah padat dan tiada liang dapat diperhatikan. Penambahan zeolit tidak mengubah struktur membran. Kata kunci: Pervaporasi, penyahidratan, membrane, kitosan, zeolite-A, isopropanol Pervaporation (PV) dehydration of isopropanol (IPA) using modified chitosan membranes was studied. The membranes were prepared from chitosan and modified by using zeolite–A. Pre–weighed amount of zeolite–A was added into acidic solvent and stirred to produce homogeneous solution. Chitosan flakes were then added into the solution and stirred overnight. Various ratios of zeolite–A and chitosan from 1:20 to 1:2 were used to produce the modified chitosan membranes. The chitosan–zeolite A solution was casted on a glass plate and dried at room temperature. The dried membranes were treated with alkaline solution and thoroughly washed in deionized water. The hydrophilicity of the membranes was studied through the swelling test. The test was carried out in a 90 wt% IPA–water mixture. The result showed that the degree of swelling decreased with the increase of the amount of zeolite–A. The mechanical properties of membranes were also tested for the tensile strength and elongation at break. Then, the membranes were investigated for the PV separation of IPA–water mixtures at the permeate pressure of 720 mmHg under vacuum. The feed concentration was varied from 0 to 95 wt% IPA, and the feed temperature was varied from 30 to 70°C. The results showed that the ratio 1:8 of zeolite–A and chitosan produced the best combination to modify the membrane for the separation of water–IPA mixtures. The structural morphologies of the chitosan filled zeolite–A membranes with ratio 1:8 and 1:2 wt zeolite–A/wt chitosan was studied under Scanning Electron Microscopy (SEM). The results showed that the membranes were dense, and no pores were visible. The addition of the zeolite did not alter the structure of the membranes. Key words: Pervaporation, dehydration, membrane, chitosan, zeolite-A, isopropanol


F1000Research ◽  
2020 ◽  
Vol 8 ◽  
pp. 1923
Author(s):  
Siska Septiana ◽  
Boy Muchlis Bachtiar ◽  
Nancy Dewi Yuliana ◽  
Christofora Hanny Wijaya

Background: Cajuputs candy (CC), an Indonesian functional food, utilizes the bioactivity of Melaleuca cajuputi essential oil (MCEO) to maintain oral cavity health. Synergistic interaction between Candida albicans and Streptococcus mutans is a crucial step in the pathogenesis of early childhood caries. Our recent study revealed several alternative MCEOs as the main flavors in CC. The capacity of CC to interfere with the fungus-bacterium relationship remains unknown. This study aimed to evaluate CC efficacy to impair biofilm formation by these dual cariogenic microbes. Methods: The inhibition capacity of CC against mixed-biofilm comprising C. albicans and S. mutans was assessed by quantitative (crystal violet assay, tetrazolium salt [MTT] assay, colony forming unit/mL counting, biofilm-related gene expression) and qualitative analysis (light microscopy and scanning electron microscopy). Result: Both biofilm-biomass and viable cells were significantly reduced in the presence of CC. Scanning electron microscopy imaging confirmed this inhibition capacity, demonstrating morphology alteration of C. albicans, along with reduced microcolonies of S. mutans in the biofilm mass. This finding was related to the transcription level of selected biofilm-associated genes, expressed either by C. albicans or S. mutans. Based on qPCR results, CC could interfere with the transition of C. albicans yeast form to the hyphal form, while it suppressed insoluble glucan production by S. mutans. G2 derived from Mojokerto MCEO showed the greatest inhibition activity on the relationship between these cross-kingdom oral microorganisms (p < 0.05). Conclusion: In general, all CC formulas showed biofilm inhibition capacity. Candy derived from Mojokerto MCEO showed the greatest capacity to maintain the yeast form of C. albicans and to inhibit extracellular polysaccharide production by S. mutans. Therefore, the development of dual-species biofilms can be impaired effectively by the CC tested.


Cerâmica ◽  
2015 ◽  
Vol 61 (360) ◽  
pp. 409-413 ◽  
Author(s):  
S. H. da Silva Filho ◽  
L. Bieseki ◽  
A. R. da Silva ◽  
A. A. B. Maia ◽  
R. A. S. San Gil ◽  
...  

Abstract The synthesis of zeolite A employing kaolin waste from paper coating was studied. The kaolin waste was pre-treated at 550 to 800 ºC. For comparison purposes, a sample of zeolite A was also prepared using the IZA procedure. The materials were characterized by 27Al MAS NMR, X-ray diffraction and scanning electron microscopy using a microprobe. Pretreatment was necessary, and the best temperatures were between 600 and 700 ºC. The zeolite A formation was observed in all the prepared materials, reaching 52% crystallinity. On the other hand, the sodalite phase and amorphous materials were also formed.


Dose-Response ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 155932582095134
Author(s):  
Pamela Nair Silva-Holguín ◽  
Simón Yobanny Reyes-López

Innovative and improved antimicrobial agents by nanotechnology are developed to control and mitigation of resistant microorganisms. Nanoparticles of metals or oxide metals be able to be toxic to bacteria, demonstrating biocidal behaviors at low concentrations. The integration of silver nanoparticles in ceramic matrices has enhanced the antimicrobial performance, resulting in the search for new composites with improved bactericidal properties. The aim of this study was to prepare and characterize hydroxyapatite-silver nanocomposite and evaluate its antimicrobial properties against various Gram-positive and negative bacteria related to drug-resistance infections. Hydroxyapatite nanopowders were produced by sol-gel and silver nanoparticles were synthesized by reduction of Ag+ions with the simple addition of gallic acid. Hydroxyapatite-silver composite (HAp-AgNPs) was prepared by adsorption of AgNPs at several concentrations. The results of UV–visible spectroscopy, dynamic light scattering, and transmission scanning electron microscopy revealed the existence of AgNPs with diameters around 6 nm. Scanning electron microscopy and energy dispersive X-ray spectroscopy corroborated the presence of silver disseminated over the surface of hydroxyapatite nanopowders. All HAp-AgNPs composites demonstrated excellent antibacterial effect even at lower silver concentration. HAp-AgNPs composites have a higher possibility for medical applications focused no the control of microorganisms with drug-resistance.


2020 ◽  
Vol 28 ◽  
pp. 04001
Author(s):  
Hasyrul Hamzah ◽  
Triana Hertiani ◽  
Sylvia Utami Tunjung Pratiwi ◽  
Titik Nuryastuti ◽  
Yosi Bayu Murti

Curcumin is a polyphenol compound that is a member of the ginger family (Zingiberaceae), which has potential as an antibacterial, antifungal, and polymicrobial antibiofilm on the catheter. Still, its inhibitory activity and eradication of non-catheter polymicrobial antibiotics against S. aureus, P. aeruginosa, E. coli, and C. albicans have never been reported. The discovery of a candidate polymicrobial anti-biofilm drug is indispensable for overcoming infections associated with biofilms. This study aims to determine the inhibitory activity and eradication of curcumin on polymicrobial biofilms. Inhibition testing and eradication activity of polymicrobial biofilms were performed using the microtiter broth method. The effectiveness of curcumin on polymicrobial biofilms was analyzed using minimum biofilm inhibition concentration (MBIC50) and minimum biofilm eradication concentration (MBEC50). The mechanism of action of curcumin against polymicrobial biofilms is tested using scanning electron microscopy (SEM). Curcumin 1 % b/v gives biofilm inhibition activity in the mid-phase and maturation of 62.23 % ± 0.01, 59.43 % ± 0.01, and can eradicate polymicrobial biofilms by 55.79 % ± 0.01 and not much different with nystatin drug control activity. The results also provide evidence that curcumin can damage the extracellular polymeric matrix (EPS) polymicrobial biofilms of S. aureus, P. aeruginosa, E. coli, and C. albicans and damage the morphology of polymicrobial biofilms. Therefore, curcumin can be developed as a candidate for new antibiofilm drugs against polymicrobial biofilms S. aureus, P. aeruginosa, E. coli dan C albicabs.


2019 ◽  
Vol 36 (2) ◽  
pp. 170-182
Author(s):  
Luisa Straulino ◽  
Luisa Mainou ◽  
Teresa Pi ◽  
Sergey Sedov ◽  
Aurelio López-Corral ◽  
...  

An almost complete cranium of a gomphoterium found in Tepeticpac, Tlaxcala, was analyzed with X-ray diffraction (XRD), Petrography and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) to stablish the transformations of the bone during its burial. The analyses assessed that the bone mineral (bioapatite) had suffered modifications in mineral composition, “crystallinity index”, cell parameters and CO2 content. However, the paleohistological structure of the bone was not significantly affected, although evidence of microbial attack was found in the bone surfaces. The filling minerals of bone macro and micro porosity were also analyzed; its main filling minerals are calcite (micrite and sparite), clays, and minerals of volcanic origin.


2018 ◽  
Vol 930 ◽  
pp. 3-7 ◽  
Author(s):  
Alexandre Fontes Melo de Carvalho ◽  
Tiago Roberto da Costa ◽  
Gilvan Pereira de Figueredo ◽  
José Antônio Barros Leal Reis Alves ◽  
Rodrigo César Santiago ◽  
...  

Optimization and reduction of zeolite A synthesis costs are the focus of several studies. Attention has been given to the use of residues and natural materials rich in Si and Al, such as diatomite. Diatomite needs to be calcined above 500°C to be used, which increases processing costs. This study aimed at evaluating the use of diatomite without calcination in preparing zeolite A. Alkaline hydrothermal synthesis melting and 24 h of crystallization were carried out. The materials were characterized by XRD (X-ray powder diffraction), XRF (X-ray fluorescence), BET (N2physisorption) and SEM (Scanning Electron Microscopy). XRD data and refinement show that the obtained material presents 99.84% crystallinity, average crystallite size of 54.92 nm, and a semi-quantitative percentage of 79% zeolite A. SiO2and Al2O3contents in the prepared sample proved the ratio SiO2/Al2O3= 2. The micrographies show cubic particles and agglomerated sodalite.


2018 ◽  
Vol 9 (1) ◽  
pp. 106-116
Author(s):  
Erick Edgar Maldonado Bandala ◽  
Karina Cabrera Luna ◽  
José Ivan Escalante García ◽  
Demetrio Nieves Mendoza

This research presents the results of concretes made with supersulfated cements (SSC) volcanic material bases. The concretes were cured under two regimes one for 24 h at 25 ° C and one for 22 h at 60 ° C and then at 25 ° C. The specimens were exposed to two conditions, dry under laboratory conditions and immersed in a solution with 3.5% CaSO 4 at 25 ° C for up to 180 days. After 180 days, the concrete with a 5% An-10% PC-10% CaO-75% PM cementant exposed to the CaSO4 solution achieved a compressive strength of 46 MPa and 44 MPa dry under conditions of laboratory. The microstructure was analyzed by scanning electron microscopy, energy dispersive spectroscopy and XRD, showing that the main hydration products are C-S-H and ettringite.


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