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Multifunctional biodegradable polymer/clay nanocomposites with antibacterial properties in drug delivery systems

Rapacz-Kmita Alicja, Szaraniec Barbara, Mikołajczyk Maciej, Stodolak-Zych Ewa, Dzierzkowska Ewa, Gajek Marcin, Dudek Piotr

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 2

83--92

EN

Purpose: The aim of this study was to investigate the possibility of intercalation of gentamicin and neomycin in montmorillonite (MMT) nanofillers, as well as to study the in vitro antimicrobial properties of nanocomposite films containing a small amount of thus obtained nanofillers. Methods: The polylactide matrix (PLA) nanocomposite films with drug-intercalated montmorillonite fillers were obtained by casting after intercalation of drugs in aqueous solutions. The efficiency of intercalation has been confirmed by X-ray diffraction (XRD) and Zeta potential measurements. The materials were studied for surface wettability, roughness and mechanical properties during 6 weeks of incubation in phosphate buffer saline, and their bactericidal activity was tested against Escherichia coli bacteria before and after 6 weeks of incubation in distilled water at 37 C. The presence of antibiotics during the incubation was monitored by conductivity and pH measurements. Results: The results indicate that nanocomposite polylactide films with montmorillonite filler intercalated with gentamicin and neomycin tend to degrade faster that their counterparts with non-intercalated fillers, which affects their mechanical properties. However, drug intercalation provided an antibacterial activity, which was confirmed by the presence of zones inhibiting the growth of Gram-negative bacteria for both antibiotics. It was also confirmed that the interaction of antibiotics with clay and polymer matrix did not adversely affect this bactericidal effect. Conclusions: Montmorillonite can be successfully intercalated with both gentamicin and neomycin, and then used as active filler for polylactide films having very good antibacterial properties, therefore their use in biomedical applications can be significantly expanded.

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Bio-Potent (5-chloro-2-thienyl)-3-(substituted Phenyl) bicyclo[2.2.1]heptane-2-yl Methanone Derivatives

Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 42

1--12

EN

A series of (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones have been synthesized by fly-ash catalyzed [4+2] cycloaddition Diels-Alder reaction of cyclopentadiene and 5-chloro-2-thienyl chalcones under cooling conditions. The yields of the methanones are more than 60%. The synthesized (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones are characterized by their physical constants and spectral data. The antimicrobial, antioxidant and insect antifeedant activities of synthesized methanones have been studied using their respective bacterial, fungal strains, DPPH radical scavenging activity and Dethler’s leaf-discs bioassay method.

3

Spectral correlation analysis and antimicrobial activities of some 2,4-dimethoxy phenyl chalcones

Joseph S. J., Arulkumaran R., Kamalakkannan D., Sakthinathan S. P., Sundararajan R., Suresh R., Vijayakumar S., Ranganathan K., Kalyanasundaram N., Vanangamudi G., Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 4

48--65

EN

A series of 2,4-dimethoxy phenyl chalcones have been synthesized by Crossed-Aldol condensation of 2,4-dimethoxy phenyl and various substituted benzaldehydes. The purities of these chalcones have been checked by their physical constants, UV, IR, NMR and MASS spectral data. The spectral data of these chalcones have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effects of substituents on the spectral group frequencies have been discussed. The anti-microbial activities of these chalcones have been evaluated using Bauer-Kirby method.

4

Assessment of substituent effects and antimicrobial activities of some 2ʹ,5ʹ-dimethyl phenyl chalcones

Joseph S. J., Kamalakkannan D., Arulkumaran R., Sakthinathan S. P., Suresh R., Sundararajan R., Vijayakumar S., Ranganathan K., Vanangamudi G., Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 5

99-123

EN

Some 2ʹ,5ʹ-dimethyl phenyl chalcones have been synthesized by Crossed-Aldol condensation between 2,5-dimethyl acetophenone and various substituted benzaldehydes using catalytic amount of sodium hydroxide and ethanol. The yields of the chalcones are more than 93 %. The purities of these chalcones have been checked by their physical constants, UV, IR, NMR and MASS spectral data. The spectral data of these chalcones have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effects of substituents on the spectral group frequencies have been discussed. The anti-microbial activities of these chalcones have been evaluated using Bauer-Kirby method.

5

Aryl Chalcones as Efficient Precursors for Deriving Oxazine: Solvent-free Synthesis and Antimicrobial Activities of some Oxazine-2-amines

Thirunarayanan G., Sundararajan R., Arulkumaran R.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 4

82--97

EN

A series of some oxazine derivatives has been synthesised by fly-ash:H2SO4 catalyzed solvent-free cyclization of aryl chalcones and urea under microwave irradiation. The yields of the oxazines were more than 85 %. The synthesised oxazines were characterized by their physical constants, analytical and spectroscopic data. The antimicrobial activities of these oxazines have been studied using Bauer-Kirby method.

6

Spectral correlations and antimicrobial activities of some 1-pyrenyl chalcones

Arulkumaran R., Vijayakumar S., Sundararajan R., Sakthinathan S.P., Kamalakkannan D., Suresh R., Ranganathan K., Rajakumar P.R.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 5

21-38

EN

A series of 1-pyrenyl chalcones have been synthesized by Crossed-Aldol condensation of 1-acetylpyrene and substituted benzaldehydes. The purities of these chalcones have been checked by their physical constants, UV, IR, NMR and MASS spectral data. The spectral data of these chalcones have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the spectral group frequencies have been discussed. The anti-microbial activities of these chalcones have been evaluated using Bauer-Kirby method.

7

Microwave assisted synthesis, spectral studies and antimicrobial activities of some 2′,4′-difluorophenyl chalcones

Vijayakumar S., Arulkumaran R., Sundararajan R., Sakthinathan S. P., Suresh R., Kamalakkannan D., Ranganathan K., Sathiyamoorthy K., Mala V., Vanangamudi G., Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 9, iss. 1

68-86

EN

Some 2′,4′-difluorophenyl chalcones have been synthesized under microwave irradiation using aldol condensation between 2,4-difluoroacetophenone and substituted benzaldehydes using catalytic amount of hydroxyapatite. The yields of the chalcones are more than 85 %. The purities of these synthesized chalcones were examined by their physical constants and spectroscopic data. The UV absorption maxima (λmax, nm), infrared stretches (ν, cm-1) of CO, fingerprint region of CHip/op, CH=CHop, C=Cop modes, NMR chemical shifts (δ, ppm) of vinyl proton, carbon and carbonyl carbons have been assigned and correlated with Hammett substituent constants, F and R parameters using single and multi-regression analysis. From the statistical analysis the effect of substituent on the above spectral frequencies can be discussed. The antimicrobial activities of these synthesized chalcones have been screened using Bauer-Kirby method.

8

Thionylchloride catalyzed aldol condensation: Synthesis, spectral correlation and antibacterial activities of some 3,5-dichloro-2-hydroxyphenyl chalcones

Arulkumaran R., Vijayakumar S., Sundararajan R., Sakthinathan S. P., Kamalakkannan D., Suresh R., Ranganathan K., Vanangamudi G., Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2012

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Vol. 4

17-38

EN

A series of substituted styryl 3,5-dichloro-2-hydroxyphenyl ketones [1-(3, 5-dichloro-2-hydroxy)- 3-phenylprop-2-en-1-one] were synthesized using thionyl chloride assisted Crossed Aldol reaction. The yields of chalcones were more than 80%. The synthesized chalcones were characterized by analytical and spectroscopic data. From the spectroscopic data the group frequencies were correlated with Hammett substituent constants, F and R parameters. From the results of statistical analysis the effect of substituents were discussed. The antibacterial activities of these chalcones have been evaluated using Bauer-Kirby method.

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Olejki eteryczne - naturalne substancje antydrobnoustrojowe

Kunicka-Styczyńska A.

Przemysł Spożywczy

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2009

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T. 63, nr 5

30-32

PL

Olejki eteryczne są substancjami pochodzenia naturalnego, wykazującymi silne działanie antydrobnoustrojowe i antyutleniające. Od wieków wprowadzane do żywności nie tylko poprawiały smak produktów, ale również je stabilizowały. W artykule omówiono pochodzenie i ogólną charakterystykę chemiczną olejków, a także właściwości bakteriostatyczne i fungistatyczne wybranych olejków eterycznych wobec mikroflory saprofitycznej lub patogennej żywności. Podano przykłady wykorzystania olejków do stabilizacji mikrobiologicznej żywności. Ze względu na istotne zmiany właściwości organoleptycznych żywności, stosowanie olejków eterycznych jako jedynych konserwantów wydaje się być ograniczone do niektórych matryc.

EN

Essential oils are substances of natural origin exhibiting strong antimicrobial and antioxidant activities. Essential oils have been added to food for ages, improving its taste and stability. The report shows an origin and general characteristics of essential oils. Bacteriostatic and fungistatic activities of chosen oils against saprophytic or pathogenic food microflora are described. The examples of essential oils application for microbiological stabilization of food are described. Because of considerable changes in sensory features of food, the use of essential oils as sole stabilizers seems to be limited to some food varieties.