« Previous AbstractChemoenzymatic Total Synthesis of (R)-4-Dodecanolide and (R)-4-Octanolide    Next AbstractMorphology of the sternal and tergal glands producing the sexual pheromones and the aphrodisiacs among the cockroaches of the subfamily oxyhaloinae »

Front Microbiol

Title:		Evaluating the Antibacterial Activity and Mode of Action of Thymol-Loaded Chitosan Nanoparticles Against Plant Bacterial Pathogen Xanthomonas campestris pv. campestris
Author(s):		Sreelatha S; Kumar N; Yin TS; Rajani S;
Address:		"Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore. Department of Biological Sciences, National University of Singapore, Singapore, Singapore"
Journal Title:		Front Microbiol
Year:		2021
Volume:		20220114
Issue:
Page Number:		792737 -
DOI:		10.3389/fmicb.2021.792737
ISSN/ISBN:		1664-302X (Print) 1664-302X (Electronic) 1664-302X (Linking)
Abstract:		"The bacterium Xanthomonas campestris pv. campestris (Xcc) causes black rot disease in cruciferous crops, resulting in severe yield loss worldwide. The excessive use of chemical pesticides in agriculture to control diseases has raised significant concern about the impact on the environment and human health. Nanoparticles have recently gained significant attention in agriculture owing to their promising application in plant disease control, increasing soil fertility and nutrient availability. In the current study, we synthesized thymol-loaded chitosan nanoparticles (TCNPs) and assessed their antibacterial activity against Xcc. The synthesis of TCNPs was confirmed by using ultraviolet-visible spectroscopy. Fourier-transform infrared spectroscopy, transmission electron microscopy, and scanning electron microscopy analysis revealed the functional groups, size, and shape of TCNPs, with sizes ranging from 54 to 250 nm, respectively. The antibacterial activity of TCNPs against Xcc was investigated in vitro by liquid broth, cell viability, and live dead staining assay, and all of them demonstrated the antibacterial activity of TCNPs. Furthermore, TCNPs were found to directly inhibit the growth of Xcc by suppressing the growth of biofilm formation and the production of exopolysaccharides and xanthomonadin. The ultrastructure studies revealed membrane damage in TCNP-treated Xcc cells, causing a release of intracellular contents. Headspace/gas chromatography (GC)-mass spectrometry (MS) analysis showed changes in the volatile profile of Xcc cells treated with TCNPs. Increased amounts of carbonyl components (mainly ketones) and production of new volatile metabolites were observed in Xcc cells incubated with TCNPs. Overall, this study reveals TCNPs as a promising antibacterial candidate against Xcc"
Keywords:		antibacterial activity biofilm inhibition mode of action nanoparticles volatiles organic compounds;
Notes:		"PubMed-not-MEDLINESreelatha, Sarangapani Kumar, Nadimuthu Yin, Tan Si Rajani, Sarojam eng Switzerland 2022/02/01 Front Microbiol. 2022 Jan 14; 12:792737. doi: 10.3389/fmicb.2021.792737. eCollection 2021"