Mechanical and antibacterial properties of ZnO/chitosan bio-composite films

Abstract In the current study, ZnO/chitosan bio-composite films were produced via solution-casting method. Two different ZnO powders, micrometer (d50 ≅ 1.5 μm) and nanometer sized (d50 ≅ 100 nm), were used to investigate the effect of ZnO particle size and concentration (0, 2, and 8% w/w of chitosan) on the mechanical and antibacterial properties of the ZnO/chitosan bio-composite films. The incorporation of the ZnO powders into the chitosan film resulted in an increase in the tensile strength (TS) and a decrease in the elongation at break (EB) values. Mechanical test results revealed that TS and EB properties were considerably affected (p < 0.05) by the concentration and particle size of the ZnO reinforcement. Disc diffusion method demonstrated good antibacterial activities of bio-composite films containing high amount of ZnO (8% w/w of chitosan) against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Bacillus subtilis. The growth-limiting effect of the films was more pronounced for S. aureus and K. pneumoniae. Due to enhanced TS and imparted antibacterial activity of the produced ZnO/chitosan bio-composite films, these materials are promising candidates for applications such as food packaging, wound dressing, and antibacterial coatings for various surfaces.

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Chemical composition and antibacterial activities of essential oils from fruits of Melicope pteleifolia (Champ. Ex Benth.) T.G. Hartley grown in Lam Dong Province, Vietnam

ACADEMIA JOURNAL OF BIOLOGY ◽

10.15625/2615-9023/v42n3.13916 ◽

2020 ◽

Vol 42 (3) ◽

Author(s):

Hoang Thi Binh ◽

Tran Thi Bao Tram ◽

Do Ngoc Dai ◽

Vuong Thuy Tien ◽

Le Minh Tam ◽

...

Keyword(s):

Mass Spectrometry ◽

Chemical Composition ◽

Essential Oil ◽

Streptococcus Pyogenes ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Gas Chromatography Mass Spectrometry ◽

Diffusion Method ◽

Aerial Parts ◽

Agar Well Diffusion Method

In the present study, chemical composition and antibacterial properties of essential oil obtained from the aerial parts of the Melicope pteleifolia (Champ. ex Benth.) T.G Hartley in Dalat were evaluated. Essential oil was isolated through hydro-distillation. Twenty-nine constituents comprising 100% of the essential oil were characterized by gas chromatography/mass spectrometry (GC-MS) techniques. The major compounds in the essential oil were (+)-Sabinene (34.73%), Cis-α-bergamotene (13.15%), Z-α-trans-bergamotol (5.28%), β-mycrene (4.98%), and 1,3,6-octatriene, 3,7-dimethyl-(4.71%). Antibacterial activities of Melicope pteleifolia essential oil were investigated against Gram-positive and-negative bacteria. Results showed significant activities against Streptococcus pyogenes and Escherichia coli using an agar well diffusion method. The application of this essential oil in preventing and eliminating bacteria could be useful in fields as medicine and cosmetics.

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Novel hybrid chitosan blended MoO3–TiO2 nanocomposite film: evaluation of its solar light photocatalytic and antibacterial activities

RSC Advances ◽

10.1039/c5ra05692f ◽

2015 ◽

Vol 5 (53) ◽

pp. 42506-42515 ◽

Cited By ~ 16

Author(s):

P. Magesan ◽

S. Sanuja ◽

M. J. Umapathy

Keyword(s):

Nanocomposite Film ◽

Antibacterial Properties ◽

Chitosan Film ◽

Antibacterial Activities ◽

Solar Light

Enhanced photocatalytic and antibacterial properties of chitosan-blended MoO3–TiO2 nanocomposite film compared to TiO2, MoO3–TiO2 nanocomposites and chitosan film.

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Graphene Oxide Reinforced Polycarbonate Nanocomposite Films with Antibacterial Properties

Indian Journal of Materials Science ◽

10.1155/2016/4169409 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

R. Mahendran ◽

D. Sridharan ◽

K. Santhakumar ◽

T. A. Selvakumar ◽

P. Rajasekar ◽

...

Keyword(s):

Thin Films ◽

Graphene Oxide ◽

Low Cost ◽

Thermal Studies ◽

Composite Films ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Nanocomposite Films ◽

Matrix Microstructure ◽

Phase Inversion Technique

The incorporation of carbonaceous nanofillers into polymers can result in significant materials with improved physicochemical properties and novel composite functionalities. In this study, we have fabricated antibacterial, lightweight, transparent, and flexible graphene oxide (GO) reinforced polycarbonate thin films by a facile and low-cost methodology. Solution blending is employed to get a homogeneous mixture of PC-GO composites at various loading of GO, and the thin films are prepared by dry-wet phase inversion technique. Thermal studies and micrographs of the films revealed the incorporation of GO in PC matrix. Microstructure of the thin films showed the homogeneous dispersion of GO at micro- and nanoscales; however, at higher loading of GO (0.7%), significant agglomeration is observed. More importantly, PC-GO composite films exhibited excellent antibacterial activities against E. coli and S. aureus, owing to the antibacterial nature of GO nanoparticles.

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Caseinate-Stabilized Emulsions of Black Cumin and Tamanu Oils: Preparation, Characterization and Antibacterial Activity

Polymers ◽

10.3390/polym11121951 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1951 ◽

Cited By ~ 2

Author(s):

Urbánková ◽

Kašpárková ◽

Egner ◽

Rudolf ◽

Korábková

Keyword(s):

Nigella Sativa ◽

Antibacterial Properties ◽

Sodium Caseinate ◽

Antibacterial Activities ◽

Diffusion Method ◽

High Shear ◽

Disk Diffusion Method ◽

Black Cumin ◽

Spoilage Bacteria ◽

High Shear Homogenization

Caseinate-stabilized emulsions of black cumin (Nigella sativa) and tamanu (Calophyllum inophyllum) oils were studied in terms of preparation, characterization, and antibacterial properties. The oils were described while using their basic characteristics, including fatty acid composition and scavenging activity. The oil-in-water (o/w) emulsions containing the studied oils were formulated, and the influence of protein stabilizer (sodium caseinate (CAS), 1–12 wt%), oil contents (5–30 wt%), and emulsification methods (high-shear homogenization vs sonication) on the emulsion properties were investigated. It was observed that, under both preparation methods, emulsions of small, initial droplet sizes were predominantly formed with CAS content that was higher than 7.5 wt%. Sonication was a more efficient emulsification procedure and was afforded emulsions with smaller droplet size throughout the entire used concentration ranges of oils and CAS when compared to high-shear homogenization. At native pH of ~ 6.5, all of the emulsions exhibited negative zeta potential that originated from the presence of caseinate. The antibacterial activities of both oils and their emulsions were investigated with respect to the growth suppression of common spoilage bacteria while using the disk diffusion method. The oils and selected emulsions were proven to act against gram positive strains, mainly against Staphylococcus aureus (S. aureus) and Bacillus cereus (B. cereus); regrettably, the gram negative species were fully resistant against their action.

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

Alternative Medicine Studies ◽

10.4081/ams.2011.e17 ◽

2011 ◽

Vol 1 (1) ◽

pp. 17 ◽

Cited By ~ 1

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

Rhynchosia scarabaeoides (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 R. scarabaeoides against five bacterial strains, Bacillus subtilis, Escherichia coli, Klebseilla pneumonia, Proteus vulgaris and Staphylococcus aureus, 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 P. vulgaris and S. aureus, whereas 2 mg was found against B. subtilis, K. pneumoniae and E. coli. 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.

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ct-DNA Binding and Antibacterial Activity of Octahedral Titanium (IV) Heteroleptic (Benzoylacetone and Hydroxamic Acids) Complexes

International Journal of Medicinal Chemistry ◽

10.1155/2016/2361214 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11

Author(s):

Raj Kaushal ◽

Sheetal Thakur ◽

Kiran Nehra

Keyword(s):

Antibacterial Properties ◽

Antibacterial Activities ◽

Spectroscopic Technique ◽

Calf Thymus Dna ◽

Diffusion Method ◽

Bacterial Strains ◽

Intercalative Mode ◽

Heteroleptic Complexes ◽

Calf Thymus ◽

Ct Dna

Five structurally related titanium (IV) heteroleptic complexes, [TiCl2(bzac)(L1–4)] and [TiCl3(bzac)(HL5)]; bzac = benzoylacetonate; L1–5 = benzohydroximate (L1), salicylhydroximate (L2), acetohydroximate (L3), hydroxyurea (L4), and N-benzoyl-N-phenyl hydroxylamine (L5), were used for the assessment of their antibacterial activities against ten pathogenic bacterial strains. The titanium (IV) complexes (1–5) demonstrated significant level of antibacterial properties as measured using agar well diffusion method. UV-Vis absorption spectroscopic technique was applied, to get a better insight into the nature of binding between titanium (IV) complexes with calf thymus DNA (ct-DNA). On the basis of the results of UV-Vis absorption spectroscopy, the interaction between ct-DNA and the titanium (IV) complexes is likely to occur through the same mode. Results indicated that titanium (IV) complex can bind to calf thymus DNA (ct-DNA) via an intercalative mode. The intrinsic binding constant (Kb) was calculated by absorption spectra by using Benesi-Hildebrand equation. Further, Gibbs free energy was also calculated for all the complexes.

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Structures and Antibacterial Properties of PLA-based Ciprofloxacin Composite Films Deposited by Low-Electron Beam Dispersion

Eurasian Chemico-Technological Journal ◽

10.18321/ectj928 ◽

2020 ◽

Vol 22 (1) ◽

pp. 35 ◽

Cited By ~ 1

Author(s):

Beibei Li ◽

Chun He ◽

Xiaohong Jiang ◽

M.A. Yarmolenko ◽

D.G. Piliptsou ◽

...

Keyword(s):

Molecular Structure ◽

Antibacterial Activity ◽

Electron Beam ◽

Agar Medium ◽

Composite Films ◽

Antibacterial Properties ◽

Diffusion Method ◽

Mass Ratio ◽

E Coli ◽

High Antibacterial Activity

Polylactic acid (PLA)-based ciprofloxacin (Cip) antibacterial films with mass ratio PLA:Cip=1:1 were prepared by low-electron beam dispersion (EBD). The molecular structure, chemical composition and morphology of PLA-based ciprofloxacin antibacterial films were investigated by XPS, FTIR, liquid NMR and SEM. The antibacterial activity of composite films was tested against E. coli ATCC 25922 and S. aureus ATCC 12600 using the agar diffusion method on the solid LB agar medium. XPS and FTIR analysis showed the presence of an antibacterial ingredient in the composite films. Using NMR, it has been shown that the molecular structure of a monolayer of ciprofloxacin is fully consistent with the molecular structure of the initial ciprofloxacin powders. High antibacterial activity of the composite films has been also established and the layers still possess antibacterial activity with regard to S. aureus even after 7 days of leaching in an isotonic solution. The thermal treatment indicates that the composite films can withstand temperatures of 180 °C and keep its structure unchanged.

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Comparative Study on the Antibacterial Properties of Nanoemulsion of Zataria multiflora Essential Oil Fortified with Cinnamaldehyde Against Common Foodborne Pathogens

The Natural Products Journal ◽

10.2174/2210315509666191111105918 ◽

2020 ◽

Vol 10 (5) ◽

pp. 631-641

Author(s):

Shahnaz Soufi ◽

Majid Aminzare ◽

Hassan Hassanzad Azar ◽

Koorosh Kamali

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Foodborne Pathogens ◽

Salmonella Enteritidis ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Diffusion Method ◽

Suitable Alternative ◽

Zataria Multiflora

Background: Nowadays, the application of several and natural preservatives in small quantity is a more preferred approach. In this regard, one of the effective methods is the formation of nanoemulsion of essential oils. Objective: The objective of this study was to compare the in vitro antibacterial activities of cinnamaldehyde (CIN) and Zataria multiflora essential oil in conventional (ZEO), nanoemulsion (NZEO) and fortified nanoemulsion (NZEOC) forms against common foodborne pathogens. Methods: Firstly, the Zataria multiflora essential oil was analyzed by GC-MS. The nanoemulsion of Z. multiflora essential oil was then prepared alone and fortified with cinnamaldehyde. Finally, their antimicrobial activity against Listeria monocytogenes, Staphylococcus aureus, Salmonella enteritidis and Escherichia coli was evaluated. Results: Based on the results, carvacrol (36.62%) was found to be the most important compound of essential oil. In disc diffusion and micro-dilution methods, the addition of CIN to ZEO during nanoemulsion formation (NZEOC) showed more antibacterial activity when compared to the individual addition of NZEO and CIN (NZEO+CIN). However, according to the vapor phase diffusion method, nano-treatments exhibited less inhibitory effects than the other treatments. Conclusion: It can be concluded that the fortification of essential oils with their derived pure compounds during nanoemulsion formation, can be used as a suitable alternative to chemical antibacterial compounds in the food industry.

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Assessment of Total Phenolic, Antioxidant, and Antibacterial Activities ofPassifloraSpecies

The Scientific World JOURNAL ◽

10.1155/2014/167309 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 13

Author(s):

Shiamala Devi Ramaiya ◽

Japar Sidik Bujang ◽

Muta Harah Zakaria

Keyword(s):

Antioxidant Activity ◽

Pathogenic Bacteria ◽

Methanol Extract ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Phenolic Antioxidant ◽

Diffusion Method ◽

Total Phenolic ◽

Leaf Extracts ◽

Methanol Extracts

This study focused on total phenolic content (TPC) and antioxidant and antibacterial activities of the leaves and stems ofPassiflora quadrangularis,P. maliformis, andP. edulisextracted using three solvents: petroleum ether, acetone, and methanol. The maximum extraction yields of antioxidant components from the leaves and stems were isolated using methanol extracts ofP. edulis(24.28%) andP. quadrangularis(9.76%), respectively. Among the leaf extracts, the methanol extract ofP. maliformishad the significantly highest TPC and the strongest antioxidant activity, whereas among the stem extracts, the methanol extract ofP. quadrangularisshowed the highest phenolic amount and possessed the strongest antioxidant activity. The antibacterial properties of thePassifloraspecies were tested using the disc diffusion method against 10 human pathogenic bacteria. The largest inhibition zone was observed for the methanol extract ofP. maliformisagainstB. subtilis. Generally, extracts from thePassifloraspecies exhibit distinct inhibition against Gram-positive but not Gram-negative bacteria. Based on the generated biplot, three clusters of bacteria were designated according to their performance towards the tested extracts. The present study revealed that methanol extracts of thePassifloracontain constituents with significant phenolic, antioxidant, and antibacterial properties for pharmaceutical and nutraceutical uses.

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In vitro antimicrobial activity of ethanolic extracts obtained from Ficus spp. leaves against the fish pathogen Aeromonas hydrophila

Archives of Polish Fisheries ◽

10.1515/aopf-2016-0019 ◽

2016 ◽

Vol 24 (4) ◽

pp. 219-230 ◽

Cited By ~ 7

Author(s):

Halyna Tkachenko ◽

Lyudmyla Buyun ◽

Elżbieta Terech-Majewska ◽

Zbigniew Osadowski

Keyword(s):

Antimicrobial Activity ◽

Aeromonas Hydrophila ◽

Bacterial Infections ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Diffusion Method ◽

Moderate Activity ◽

In Vitro Antimicrobial Activity ◽

Ethanolic Extracts

Abstract The main goal of this study was to determine in vitro antimicrobial activity of ethanolic extracts obtained from the leaves of various Ficus species against Aeromonas hydrophila isolated locally from infected rainbow trout (Oncorhynchus mykiss Walbaum) with the aim of providing scientific rationale for the use of the plant in the treatment of bacterial infections induced by Aeromonas spp. in fish. Antimicrobial susceptibility testing was done on Muller-Hinton agar with the disc diffusion method. In the present study, most ethanolic extracts proved effective against the A. hydrophila tested, with 10-12 mm inhibition zones observed. A. hydrophila demonstrated the highest susceptibility to F. pumila. Among various species of Ficus with moderate activity against A. hydrophila, the highest antibacterial activities were noted for F. benghalensis, F. benjamina, F. deltoidea, F. hispida, and F. lyrata. Thus, Ficus can be used as a natural antiseptic and antimicrobial agent in veterinary practice. Further investigations need to be conducted to isolate and identify the bioactive compounds that can then be subjected to detailed pharmacological studies and the development of clinical applications. The alarming rate of increasing resistance in bacterial pathogens in aquaculture environments means that medicinal plants with antibacterial properties are very important as natural resources of new active compounds.

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