Marine bacteria (Bacillus cereus, Bacillus sphericus, Vibrio furnisii, and Brevundimonas vesicularis) were shown to degrade nylon 6 and 66 in mineral salt medium at 35 °C and pH of 7.5 under submerged enrichment conditions with the polymer as the sole carbon source. The degradation led to the formation of new functional groups NHCHO, CH3, CONH2, CHO and COOH. Maximum degradation was observed with Bacillus cereus for both the nylons. Average molecular weight decreased by 42% and 31% and weight decreased by 7% and 2% in the case of nylon 66 and nylon 6, respectively, over a period of three months. Differential scanning calorimetry showed a reduction in melting temperature (∼ of 1 °C) and enthalpies of fusion indicating decrease in crystallinity. Epi-fluorescent microscope of the degraded samples showed surface stripping and groves. The extent of degradation observed with the marine organisms was better than soil organisms reported in the literature. © 2007 Elsevier Ltd. All rights reserved.

Mukesh Doble

Department Of Biotechnology

Bacteria

Degradation

Differential scanning calorimetry

enthalpy

Functional groups

FUSION REACTIONS

Marine biology

melting point

Molecular weight

Bacillus cereus

EPI-FLUORESCENT MICROSCOPE

MARINE BACTERIA

Marine organisms

SUBMERGED ENRICHMENT CONDITIONS

Nylon polymers

bacterium

Biodegradation

Calorimetry

marine ecosystem

Melting

polymer

BACILLUS (BACTERIUM)

Bacteria (microorganisms)

BREVUNDIMONAS

BREVUNDIMONAS VESICULARIS

VIBRIO

VIBRIO FURNISSII

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

International Biodeterioration and Biodegradation

Biofouling in the marine environment is a major problem. In this study, three marine organisms, namely Bacillus flexus (LD1), Pseudomonas fluorescens (MD3) and Vibrio natriegens (MD6), were isolated from biofilms formed on polymer and metal surfaces immersed in ocean water. Phylogenetic analysis of these three organisms indicated that they were good model systems for studying marine biofouling. The in vitro antifouling activity of 47 synthesized chalcone derivatives was investigated by estimating the minimum inhibitory concentration against these organisms using a twofold dilution technique. Compounds C-5, C-16, C-24, C-33, C-34 and C-37 were found to be the most active. In the majority of the cases it was found that these active compounds had hydroxyl substitutions. A quantitative structure-activity relationship (QSAR) was developed after dividing the total data into training and test sets. The statistical measures r2, radj2 (&gt;0.6) q2 (&gt;0.5) and the F-ratio were found to be satisfactory. Spatial, structural and electronic descriptors were found to be predominantly affecting the antibiofouling activity of these compounds. Among the spatial descriptors, Jurs descriptors showed their contribution in all the three antibacterial QSARs. © 2010 Taylor &amp; Francis.

SAR and QSAR in Environmental Research

Antibacterial activity and QSAR of chalcones against biofilm-producing bacteria isolated from marine waters

Polymer Degradation and Stability

Studies on the decomposition behavior of nylon-66 in supercritical water

Polyamide-6 fibre degradation by a lignolytic fungus

Isolation of a thermophilic bacterium degrading some nylons

Biotechnology Letters

10.1023/a:1026091711130

Polymers for Advanced Technologies

Degradation of polyamide-6 by using metal salts as catalyst

Marine bacteria mediated degradation of nylon 66 and 6

Journal	International Biodeterioration and Biodegradation
ISSN	09648305
Open Access	No