scholarly journals Antibacterial Nanocomposites Based on Fe3O4–Ag Hybrid Nanoparticles and Natural Rubber-Polyethylene Blends

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Thanh Dung Ngo ◽  
Thi My Hanh Le ◽  
The Huu Nguyen ◽  
Thien Vuong Nguyen ◽  
Tuan Anh Nguyen ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Natural Rubber ◽  
Antibacterial Activities ◽  
Hybrid Nanoparticles ◽  
Growth Phases ◽  
Elongation At Break ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Polyethylene Blends ◽  
Internal Mixer

For the vulcanized natural rubber (NR), incorporation of silver nanoparticles (AgNPs) into the NR matrix did not exhibit the bactericidal property against Escherichia coli (E. coli). However, incorporation of AgNPs into polyethylene (PE) matrix showed good antibacterial activities to both Gram-negative and Gram-positive bacteria. In the present work, NR/PE (85/15) blends have been prepared by melt blending with presence of compatibilizer in an internal mixer. To possess antibacterial property, AgNPs (5–10 nm) or Fe3O4–Ag hybrid nanoparticles (FAgNPs, 8 nm/16 nm) were added into PE matrix before its blending with NR component. The tensile test indicated that the presence of compatibilizer in NR/PE blend significantly enhanced the tensile strength and elongation at break (up to 35% and 38% increases, resp.). The antibacterial activity test was performed by monitoring of the bacterial lag-log growth phases with the presence of nanocomposites in the E. coli cell culture reactor. The antibacterial test showed that the presence of FAgNPs in NR/PE blend had a better antibacterial activity than that obtained with the lone AgNPs. Two similar reasons were proposed: (i) the faster Ag+ release rate from the Fe3O4–Ag hybrid nanoparticles due to the electron transfer from AgNP to Fe3O4 nanoparticle and (ii) the fact that the ionization of AgNPs in hybrid nanostructure might be accelerated by Fe3+ ions.

scholarly journals Enhancement of the Antibacterial Activity of Natural Rubber Latex Foam by Blending It with Chitin

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1039 ◽  
Author(s):  
Nanxi Zhang ◽  
Hui Cao
Keyword(s):  
Antibacterial Activity ◽  
Natural Rubber ◽  
Natural Rubber Latex ◽  
Inhibition Zone ◽  
Rubber Latex ◽  
Culture Dish ◽  
Elongation At Break ◽  
E Coli ◽  
Chitin Content ◽  
Foaming Process

To enhance the antibacterial activity of natural rubber latex foam (NRLF), chitin was added during the foaming process in amounts of 1–5 phr (per hundred rubber) to prepare an environmentally friendly antibacterial NRLF composite. In this research, NRLF was synthesized by the Dunlop method. The swelling, density, hardness, tensile strength, elongation at break, compressive strength and antibacterial activity of the NRLFs were characterized. FTIR and microscopy were used to evaluate the chemical composition and microstructure of the NRLFs. The mechanical properties and antibacterial activity of the NRLF composites were tested and compared with those of pure NRLF. The antibacterial activity was observed by the inhibition zone against E. coli. NRLF composite samples were embedded in a medium before solidification. The experimental results of the inhibition zone indicated that with increasing chitin content, the antibacterial activity of the NRLF composites increased. When the chitin content reached 5 phr, the NRLF composite formed a large and clear inhibition zone in the culture dish. Moreover, the NRLF–5 phr chitin composite improved the antibacterial activity to 281.3% of that of pure NRLF against E. coli.

scholarly journals Antioxidant and antibacterial activity of extract from two species of mosses: Leucobryum aduncum and Campylopus schmidii

2020 ◽  
Vol 21 (6) ◽  
Author(s):  
Maria Masitho Makajanma ◽  
Intan Taufik ◽  
Ahmad Faizal
Keyword(s):  
Antioxidant Activity ◽  
Antibacterial Activity ◽  
Antibacterial Activities ◽  
Gas Chromatography Mass Spectrometry ◽  
Lipophilic Compounds ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Medicinal Value ◽  
New Antibiotics ◽  
Polar Extracts

Abstract. Makajanma MM, Taufik I, Faizal A. 2020. Antioxidant and antibacterial activity of extract from two species of mosses: Leucobryum aduncum and Campylopus schmidii. Biodiversitas 21: 1751-1758.  Plants produce a plethora of natural compounds of medicinal value. Although most plant-derived drugs have been identified in angiosperms, some species of mosses from the genera Leucobryum and Campylopus also exhibit antioxidant and antibacterial activity. The research aimed to evaluate the antioxidant and antibacterial activities of two species of these genera, Leucobryum aduncum and Campylopus schmidii, that are common in Taman Wisata Alam Gunung Tangkuban Perahu, West Java. Plants were collected, dried, and extracted in n-hexane or methanol. Antioxidant activity was evaluated by determining the concentration of extract that resulted in 50% reduction of 1,1-diphenyl-2-picrylhydrazine (DPPH) in the DPPH assay. These concentrations were >2000 mg/L for L. aduncum extracts and 1329.02 ± 7.8 mg/L for C. schmidii extracts; these large values are consistent with little antioxidant activity. Antibacterial activity was quantified as the ability of the extracts to inhibit the growth of the Gram-negative and Gram-positive bacteria Escherichia coli and Staphylococcus aureus, respectively. Nonpolar extracts of L. aduncum inhibited the growth of E. coli >50% at a concentration of 32 mg extract/L. Based on combined gas chromatography-mass spectrometry, the antibacterial activity in the non-polar extracts of L. aduncum was attributed to the lipophilic compounds 1-nonadecene, 5-eicosene, and cyclotetracosane. Thus, L. aduncum is a promising candidate as a source of new antibiotics.

scholarly journals IN VITRO ANTIBACTERIAL ACTIVITIES OF DIFFERENT SOLVENT EXTRACTS OF CAJANUS CAJAN L. SEED COAT AND COTYLEDON

2018 ◽  
Vol 11 (5) ◽  
pp. 325
Author(s):  
Pratima H ◽  
Pratima Marthad
Keyword(s):  
Antibacterial Activity ◽  
Seed Coat ◽  
Cajanus Cajan ◽  
Ethanolic Extract ◽  
Antibacterial Activities ◽  
Salmonella Typhi ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Successive Extraction

 Objectives: The present study was conducted to assess the antibacterial activity of seed coat and cotyledon of Cajanus cajan with various solvents such as petroleum ether, chloroform, ethanol, and aqueous.Methods: The crude extracts were obtained using Soxhlet successive extraction method. The antibacterial activity of seed coat and cotyledon extracts at different concentration (50 and 100 mg/mL) was evaluated against certain pathogenic Gram-positive bacteria of Bacillus subtilis, Staphylococcus aureus, and Streptococcus pneumoniae and Gram-negative bacteria of Salmonella typhi, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa by agar well diffusion assay.Results: The results show that the ethanolic extract of seed coat had highest activity against B. subtilis (22.0±0.13 mm). Whereas, the aqueous extract of cotyledon had highest activity against S. aureus (20.0±0.02 mm) and S. typhi (20.0±0.04 mm) at 100 mg/mL. The S. pneumoniae and P. aeruginosa were completely resistant to all extracts of seed coat. Similarly, S. pneumoniae, K. pneumoniae, E. coli, and P. aeruginosa were totally resistant to all tested cotyledon extracts. The phytochemical results show the presence of alkaloids, steroids, phenols, flavonoids, tannins, lignins, glycosides, and absence of saponins in seed coat and cotyledon.Conclusion: This study shows that C. cajan seed coat and cotyledon had potential antibacterial activity against B. subtilis, S. aureus, and S. typhi. These extracts may be exploited for the development of antimicrobial and alternative remedies for infections and diseases caused by respective pathogens.

scholarly journals SINTESIS NANOPARTIKEL KOBALT FERRIT (CoFe2O4) MENGGUNAKAN EKSTRAK DAUN BINAHONG (Anredera cordifolia (Ten) Steenis) DAN APLIKASINYA SEBAGAI ANTIBAKTERI

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Charissa L. Luntungan ◽  
Henry F. Aritonang ◽  
Vanda S. Kamu
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Leaf Extract ◽  
Antibacterial Activities ◽  
Clear Zone ◽  
Cofe2o4 Nanoparticles ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria

ABSTRAKTelah dilakukan penelitian mengenai sintesis nanopartikel CoFe2O4 menggunakan ekstrak daun binahong (Anredera cordifolia (Ten) Steenis). dengan variasi perbandingan mol (Co(NO3)2.6H2O) : (Fe(NO3)3.9H2O) = 1:1 dalam 15 mL. Nanopartikel tersebut dikarakterisasi menggunakan XRD dan SEM serta diuji aktivitas antibakterinya. Uji aktivitas antibakteri mengunakan bakteri Staphylococcus aureus (gram-positif) dan Escherichia coli (gram-negatif). Hasil penelitian menunjukan bahwa ukuran nanopartikelnya adalah 37,52 nm. Kemudian aktivitas antibakteri diketahui berdasarkan luasnya zona bening yang terbentuk dengan hasil diperoleh sebesar 15 mm untuk bakteri E.coli dan 20 mm untuk bakteri S.aureus. Daun Binahong sendiri memiliki sifat sebagai antibakteri dengan hasil yang didapat adalah 8,25 mm untuk bakteri E.coli  dan 10,25 mm untuk bakteri S.aureus. Hal ini menunjukan bahwa nanopartikel CoFe2O4 1 : 1 dalam 15 mL ekstrak dapat digunakan sebagai antibakteriABSTRACTIt has been done research on the synthesis of CoFe2O4 nanoparticles using binahong (Anredera cordifolia (Ten) Steenis) leaf extract. With comparison mol variation of (Co(NO3)2.6H2O) : (Fe(NO3)3.9H2O) = 1:1 in 15 mL extract. The nanoparticles were characterized using XRD and SEM and tested for their antibacterial activities. Test antibacterial activity using Staphylococcus aureus (gram-positive) bacteria and Escherichia coli (gram-negative). The results showed that the nanoparticle size was 37.52 nm. Antibacterial activity is known by the extent of the clear zone formed with the results obtained by 15 mm for the E. coli bacteria and 20 mm for the bacteria S. aureus. The leaf Binahong itself has a trait as an antibacterial with the results obtained is 8.25 mm for the bacteria E. coli and 10.25 mm for the S.aureus bacteria. This suggests that the CoFe2O4 nanoparticles 1:1 mol in 15 mL extrack are used as antibacterial. 

Synthesis of Chalcones and Nucleosides Incorporating [1, 3, 4]Oxadiazolenone Core and Evaluation of their Antifungal and Antibacterial Activities

2020 ◽  
Vol 15 (6) ◽  
pp. 665-679
Author(s):  
Alok K. Srivastava ◽  
Lokesh K. Pandey
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Antifungal Activity ◽  
Aspergillus Niger ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Good Antibacterial Activity

Background: [1, 3, 4]oxadiazolenone core containing chalcones and nucleosides were synthesized by Claisen-Schmidt condensation of a variety of benzaldehyde derivatives, obtained from oxidation of substituted 5-(3/6 substituted-4-Methylphenyl)-1, 3, 4-oxadiazole-2(3H)-one and various substituted acetophenone. The resultant chalcones were coupled with penta-O-acetylglucopyranose followed by deacetylation to get [1, 3, 4] oxadiazolenone core containing chalcones and nucleosides. Various analytical techniques viz IR, NMR, LC-MS and elemental analysis were used to confirm the structure of the synthesised compounds.The compounds were targeted against Bacillus subtilis, Staphylococcus aureus and Escherichia coli for antibacterial activity and Aspergillus flavus, Aspergillus niger and Fusarium oxysporum for antifungal activity. Methods: A mixture of Acid hydrazides (3.0 mmol) and N, Nʹ- carbonyl diimidazole (3.3 mmol) in 15 mL of dioxane was refluxed to afford substituted [1, 3, 4]-oxadiazole-2(3H)-one. The resulted [1, 3, 4]- oxadiazole-2(3H)-one (1.42 mmol) was oxidized with Chromyl chloride (1.5 mL) in 20 mL of carbon tetra chloride and condensed with acetophenones (1.42 mmol) to get chalcones 4. The equimolar ratio of obtained chalcones 4 and β -D-1,2,3,4,6- penta-O-acetylglucopyranose in presence of iodine was refluxed to get nucleosides 5. The [1, 3, 4] oxadiazolenone core containing chalcones 4 and nucleosides 5 were tested to determined minimum inhibitory concentration (MIC) value with the experimental procedure of Benson using disc-diffusion method. All compounds were tested at concentration of 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.62 mg/mL, 0.31 mg/mL and 0.15 mg/mL for antifungal activity against three strains of pathogenic fungi Aspergillus flavus (A. flavus), Aspergillus niger (A. niger) and Fusarium oxysporum (F. oxysporum) and for antibacterial activity against Gram-negative bacterium: Escherichia coli (E. coli), and two Gram-positive bacteria: Staphylococcus aureus (S. aureus) and Bacillus subtilis(B. subtilis). Result: The chalcones 4 and nucleosides 5 were screened for antibacterial activity against E. coli, S. aureus and B. subtilis whereas antifungal activity against A. flavus, A. niger and F. oxysporum. Compounds 4a-t showed good antibacterial activity whereas compounds 5a-t containing glucose moiety showed better activity against fungi. The glucose moiety of compounds 5 helps to enter into the cell wall of fungi and control the cell growth. Conclusion: Chalcones 4 and nucleosides 5 incorporating [1, 3, 4] oxadiazolenone core were synthesized and characterized by various spectral techniques and elemental analysis. These compounds were evaluated for their antifungal activity against three fungi; viz. A. flavus, A. niger and F. oxysporum. In addition to this, synthesized compounds were evaluated for their antibacterial activity against gram negative bacteria E. Coli and gram positive bacteria S. aureus, B. subtilis. Compounds 4a-t showed good antibacterial activity whereas 5a-t showed better activity against fungi.

scholarly journals A novel bis(pyrazolyl)methane compound as a potential agent against Gram-positive bacteria

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pedro Seguí ◽  
John J. Aguilera-Correa ◽  
Elena Domínguez-Jurado ◽  
Christian M. Sánchez-López ◽  
Ramón Pérez-Tanoira ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Effect ◽  
Eukaryotic Cell ◽  
Liver Carcinoma ◽  
Gram Positive ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Therapeutic Compounds ◽  
Toxic Concentrations

AbstractThis study was designed to propose alternative therapeutic compounds to fight against bacterial pathogens. Thus, a library of nitrogen-based compounds bis(triazolyl)methane (1T–7T) and bis(pyrazolyl)methane (1P–11P) was synthesised following previously reported methodologies and their antibacterial activity was tested using the collection strains of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa. Moreover, the novel compound 2P was fully characterized by IR, UV–Vis and NMR spectroscopy. To evaluate antibacterial activity, minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), minimum biofilm inhibitory concentrations (MBICs), and minimum biofilm eradication concentrations (MBECs) assays were carried out at different concentrations (2–2000 µg/mL). The MTT assay and Resazurin viability assays were performed in both human liver carcinoma HepG2 and human colorectal adenocarcinoma Caco-2 cell lines at 48 h. Of all the synthesised compounds, 2P had an inhibitory effect on Gram-positive strains, especially against S. aureus. The MIC and MBC of 2P were 62.5 and 2000 µg/mL against S. aureus, and 250 and 2000 µg/mL against E. faecalis, respectively. However, these values were > 2000 µg/mL against E. coli and P. aeruginosa. In addition, the MBICs and MBECs of 2P against S. aureus were 125 and > 2000 µg/mL, respectively, whereas these values were > 2000 µg/mL against E. faecalis, E. coli, and P. aeruginosa. On the other hand, concentrations up to 250 µg/mL of 2P were non-toxic doses for eukaryotic cell cultures. Thus, according to the obtained results, the 2P nitrogen-based compound showed a promising anti-Gram-positive effect (especially against S. aureus) both on planktonic state and biofilm, at non-toxic concentrations.

Preparation of bioactive and antibacterial PMMA-based bone cement by modification with quaternary ammonium and alkoxysilane

2021 ◽  
pp. 088532822110044
Author(s):  
Haiyang Wang ◽  
Toshinari Maeda ◽  
Toshiki Miyazaki
Keyword(s):  
Antibacterial Activity ◽  
Methyl Methacrylate ◽  
Bone Cement ◽  
Setting Time ◽  
Antibacterial Properties ◽  
The Body ◽  
Apatite Formation ◽  
Gram Positive ◽  
E Coli ◽  
Gram Positive Bacteria

Bone cement based on poly(methyl methacrylate) (PMMA) powder and methyl methacrylate (MMA) liquid is a very popular biomaterial used for the fixation of artificial joints. However, there is a risk of this cement loosening from bone because of a lack of bone-bonding bioactivity. Apatite formation in the body environment is a prerequisite for cement bioactivity. Additionally, suppression of infection during implantation is required for bone cements to be successfully introduced into the human body. In this study, we modified PMMA cement with γ-methacryloxypropyltrimetoxysilane and calcium acetate to introduce bioactive properties and 2-( tert-butylamino)ethyl methacrylate (TBAEMA) to provide antibacterial properties. The long-term antibacterial activity is attributed to the copolymerization of TBAEMA and MMA. As the TBAEMA content increased, the setting time increased and the compressive strength decreased. After soaking in simulated body fluid, an apatite layer was detected within 7 days, irrespective of the TBAEMA content. The cement showed better antibacterial activity against Gram-negative E. Coli than Gram-positive bacteria; however, of the Gram-positive bacteria investigated, B. subtilis was more susceptible than S. aureus.

scholarly journals A comparison of the antibacterial activity of some African black soaps and medicated soaps commonly used for the treatment of bacteria-infected wound

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Olufunmiso O. Olajuyigbe ◽  
Morenike O. Adeoye-Isijola ◽  
Otunola Adedayo
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Concentration ◽  
Waste Product ◽  
Antibacterial Activities ◽  
Traditional Use ◽  
E Coli ◽  
African Black ◽  
Soap Production ◽  
Inhibition Zones ◽  
Better Than

Background: Black soap is a medicinal product that could be harnessed for economic purpose if properly packaged, and misconception about its traditional use by herbalists is thrown overboard.Aims: To promote the relevance of these soaps for economic development, this study compared the antibacterial activity of black soaps with medicated soaps widely used against bacterial infections.Methods: The antibacterial activities of these soap samples were determined by agar diffusion and macrobroth dilution methods.Results: In this study, the statistical analysis of the inhibition zones showed that black soaps were significantly (p < 0.05) more active than medicated soaps used against the test bacterial isolates. The black soaps inhibited and killed the isolates better than the medicated soaps at the different concentrations used. The minimum inhibitory concentration for Klebsiella pneumoniae and Enterococcus faecalis ranged between 0.125 mg/mL and 2 mg/mL, Staphylococcus aureus (0.25–4) mg/mL, Escherichia coli (0.125–4) mg/mL and Pseudomonas aeruginosa (1–4) mg/mL. The result showed that K. pneumoniae and E. faecalis were the most susceptible, followed by E. faecalis > E. coli > S. aureus > P. aeruginosa.Conclusion: As a valuable medicinal output derivable from organic waste product that could be converted to wealth, African black soap production, utilisation and commercialisation have tremendous economic potentials. These soaps showed significant antibacterial activity greater than those of the medicated soaps. Hence, their use could be a better option in place of commercially available medicated and antiseptic soaps because of the degree of antibacterial activities they exhibited.

Toughness Enhancement of Polylactic Acid by Employing Glycolyzed Polylactic Acid-Cured Epoxidized Natural Rubber

2014 ◽  
Vol 1025-1026 ◽  
pp. 580-584 ◽  
Author(s):  
Phrutsadee Sukpuang ◽  
Mantana Opaprakasit ◽  
Atitsa Petchsuk ◽  
Pakorn Opaprakasit
Keyword(s):  
Natural Rubber ◽  
Polylactic Acid ◽  
Epoxidized Natural Rubber ◽  
Chemical Recycling ◽  
Crosslinking Reaction ◽  
Solvent Fractionation ◽  
Elongation At Break ◽  
Chemical Structures ◽  
Internal Mixer ◽  
Toughness Enhancement

Glycolyzed polylactic acid (GPLA)-cured epoxidized natural rubber (ENR) is developed for use as a toughening agent for PLA resin. GPLA is obtained from chemical recycling of PLA resin by a glycolysis reaction. GPLA-cured ENR is then prepared by the crosslinking reaction of ENR with GPLA in an internal mixer. Chemical structures of the cured products are characterized by solvent fractionation and thermogravimetric analysis (TGA). The cured ENR products are blended with PLA resin, by varying the cured ENR contents from 5 to 15% wt. Mechanical properties of the blends, and their toughening mechanisms are examined. The cured ENR materials has higher efficiency in improving toughness of PLA resin, compared to uncured ENR, likely due to their rubbery network nature and higher compatibility with the PLA matrix. The incorporation of 5% wt. GPLA-cured ENR also improves elongation at break with no adverse effect on tensile strength and modulus of PLA.

Improvement of Mechanical Properties and Water Absorption in Wheat Gluten by Epoxidized Natural Rubber

2019 ◽  
Vol 891 ◽  
pp. 163-168
Author(s):  
Kantima Chaochanchaikul
Keyword(s):  
Natural Rubber ◽  
Water Absorption ◽  
Thermal Analyses ◽  
Wheat Gluten ◽  
Research Work ◽  
Decomposition Temperature ◽  
Epoxidized Natural Rubber ◽  
Elongation At Break ◽  
Opposite Behavior ◽  
Internal Mixer

TThe aims of this research work were to improve touhgness and water resistance of wheat gluten (WG) by epoxidized natural rubber (ENR) compared to glycerol. WG specimens were mixed and prepared by internal mixer and compression molding machine, respectively. ENR and glycerol were varied from 10 to 40 wt%. Effects of modifier types and contents on WG were evaluated by tensile, impact and water absorption testings and microstructure and thermal analyses. The increase of ENR or glycerol contents led to the increase of toughness by considering the increase of impact strength and elongation at break. Glass transition temperature of WG tended to decrease with the increase of ENR or glycerol contents, especially for glycerol. The presence of glycerol affected to the decomposition temperature values whereas ENR did not affect to decomposition. ENR improved water resistant of WG specimen but trend of glycerol showed the opposite behavior. Weight loss of modified WG with glycerol was found at immersion time of 1440 min.

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