Assessment of Antibacterial Activity

Quantitative tests for the antibacterial activity of textiles usually involve sterilisation of the fabric, followed by its inoculation with a test organism and incubation prior to determination of the number of bacteria remaining on the fabric. Qualitative tests for such activity consist of visual observation of microbial growth on the fabric after 

The disadvantages of quantitative methods are that they are time-consmning, expensive, and they have not been assessed (with the exception of the American Association of Textile Chemists and Colorists (AATCC)-IOO method) for interlaboratory correlation of test results. Three quantitative methods are currently being nsed for determining 

Generally, the bacteriostatic activity of colloidal silver nanoparticles is evaluated after a given contact time and the percentage reduction of bacteria is calculated using Equation 1.1  

Have no adverse effects on mammalian cell membranes. 

Selective activity against undesirable microorganisms Durable to washing, dry cleaning and hot pressing. 

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Spooner, D. F. and Sykes, G. Laboratory assessment of antibacterial activity. Meth Microbiol 78,211-276. 

From an assessment of antibacterial activity, the resnlts show that untreated, plasma treated and acrylic-acid grafted samples did not display any antibacterial activity against strains of Escherichia coli and Staphylococcus aureus. The sample coated with triclosan met the expected antibacterial requirements and similar results were obtained for chlorhexidine-coated samples, with the average inhibition zone of 42.2 mm for Escherichia coli and 288.1 mm for Staphylococcus aureus. It is worth mentioning that both antibacterial agents are more active against Gram-positive bacteria. Finally, triclosan coated-samples showed the best results of the two antibacterial substances used. 

The most popular methods of synthesizing silver nanoparticles, the antibacterial properties of silver nanoparticles, their interactions with microorganisms, and assessment of antibacterial activity are the most important issues which will be discussed here. 

Doxycycline-loaded chitosan microspheres were developed using a novel water-inoil emulsion technique, involving oil phase ionic gelation. Assessment of antibacterial activity showed that doxycycline was able to exhibit a minimum microbicidal concentration (MIC) of 16.5,17.4,11.2 and 98.3 pg a gdinst Klebsiella pneumoniae (ATCC 15380), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 9144) and Pseudomonas aeruginosa (ATCC 25619), respectively. The scope of this investigation was the use of doxycycline-loaded chitosan microspheres for healing infected wounds [86]. 

Quantitative Assessment of Antibacterial Activity on Carpets AATCC Test Method 174-1991 Part II... 

XIN 12] Xing Z.-C., Meng W., Yuan J. et al., In Vitro Assessment of Antibacterial Activity and Cytocompatibility of Quercetin-Containing PLGA Nanofibrous Scaffolds for Tissue Engineering , Journal of Nanomaterials, Article ID 202608, vol. 2012, p. 7, 2012. 

Assessment of Antibacterial Finishes on Textile Materials Methods 100 , American Association of Textile Chemist and Colorist, 1993. Antimicrobial Activity Assessment of Carpets Method 174 , American Association of Textile Chemist and Colorist, 1993. 

However, it should be taken into account that essential oils are mnch more active in the in vitro conditions than in in situ (e.g. in food and cosmetic) or in vivo (in patients) model systems. The effective content of individnal essential oil is nsn-ally too high to be acceptable for the application to food prodncts becanse of the intensity of aroma. In the last decade, the assessments of antibacterial and antifnn-gal activity of essential oils in prodnct model systems have been more and more numerous. Such research revealed synergistic or at least additive effects in the mixtures of essential oils or essential oil with other food additives (Bassole et al. 2010 Tajkarimi et al. 2010). This snggests that such mixtures could be used in order to diminish the odor of each individual component and improve the preservative properties. Essential oils therefore wiU continue to be indispensable natural ingredients and they may provide alternatives to conventional antimicrobial additives in food. 

Delespaul Q, BiUerbeck VG, Roques Ch et al (2000) The antifungal activity of essentied oils as determined by different screening methods. J Essent Oil Res 12 256-266 Donaldson JR, Warner SL, Cates RG et al (2005) Assessment of antimicrobial activity of fourteen essential oils when using dilution and diffusion methods. Pharm Biol 43 687-695 Dorman HJD, Deans SG (2000) Antimicrobial agents from plants antibacterial activity of plant volatile oils. J Appl Microbiol 88 308-316... 

The coordination shell comprises three fac-S and three fac-N-donor atoms in [Fe(6mp)3] [FeClJCl, where 6mp = 6-thiopurine, (189). Both iron(II) and iron(III) complexes are included in a review of transition metal complexes of thiosemicarbazones. " 5,5 -Dimethyl-l,2,3-cyclohex-anetrione-l,2-dioxime-3-thiosemi-carbazone, dcdt (190), acts as an A, A, 5 -donor to Fe +, giving a bis-ligand complex (contrast [Fe(7V,7V -dcdt)3] with Fe " "). The Schiff bases from pyridine 2-carboxaldehyde and thiosemicarbazide or 4-phenyl thiosemicarbazide also act as A, VV, 5 -donors, both to Fe " " and to Fe " ". The antibacterial activity of these complexes was assessed, in... 

AATCC Test Method 147-1998, Antibacterial activity assessment of textile materials parallel streak method , Technical Manual of the American Association of Textile Chemists and Colorists, Research Triangle Park, American Association of Textile Chemists and Colorists, 2003, 261-262. 

AATTC 147 2004 Antibacterial Activity Assessment of Textile Materials Parallel Streak Method (a. 14)... 

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