Activity of chitosan–lysozyme nanoparticles on the growth, membrane integrity, and β-1,3-glucanase production by Aspergillus parasiticus

Abstract

Synthesis of nanocomposites from antimicrobial biopolymers such as chitosan (CS) and lysozyme (LZ) is an important and promising area in bionanotechnology. Chitosan-lysozyme (CS-LZ) nanoparticles (NPs) were prepared by the nanoprecipitation method, using commercial chitosan of 153 kDa. TEM and dynamic light scattering (DLS) analysis were carried out to evaluate the morphology, size, dispersion, and Z potential. Association efficiency of lysozyme was determined using Coomassie blue assay. The antifungal activity of NPs against was evaluated through cell viability (XTT), germination and morphometry of spores, and reducing sugars production; the effects on membrane integrity and cell wall were also analyzed. NPs' size were found in the range of 13.4 and 11.8 nm for CS-LZ and CS NPs, respectively, and high Z potential value was observed in both NPs. Also, high association of lysozyme was presented in the CS matrix. With respect to the biological responses, CS-LZ NPs reduced the viability of and a strong inhibitory effect on the germination of spores (100% of inhibition) was observed at 24 h in in vitro assays. CS-LZ and CS NPs affected the membrane integrity and the cell wall of spores of fungi with respect to control, which is consistent with the low amount of reducing sugars detected. CS-LZ NPs prepared by nanoprecipitation promise to be a viable and safe alternative for use in biological systems, with a possible low or null impact to humans and biota. However, the potential benefits and the environmental and health implications of NPs need to be globally discussed due to its possible negative effects.

In vitro PCR verification that lysozyme inhibits nucleic acid replication and transcription

“…With advances in research, antifungal mechanisms of lysozyme have been elucidated 46 – 48 . In addition to its enzyme activity and cationic nature, studies have shown that the loss of mitochondrial membrane potential, the exposure of phosphatidylserine in the outer leaflets of the cell membrane, chromatin condensation, and DNA damage may all be factors in how lysozyme affects the structure and death of fungi 47 , 49 . By incubating lysozyme with cell lines, we found that the extracellular fluid after incubation did not exhibit a nucleic acid inhibitory effect, while the intracellular fluid had nucleic acid inhibitory activity.…”

Tetrandrine Derivatives as Promising Antibacterial Agents

“…2′,7′-Dichlorodihydrofluorescein diacetate (2,7-DCFH 2 -DA) is a nonfluorescent cell-permeable dye that is hydrolyzed intracellularly to its polar but nonfluorescent form DCFH 2 , on the action of cellular esterase enzymes and thus is retained in the cell. Oxidation of DCFH 2 by the action of intracellular reactive oxygen species (ROS) and other peroxides turns the molecule into its highly fluorescent form (DCF) that can be detected by various fluorescent methods . Considering this mentioned, the 2,7-DCFH 2 -DA dye was employed according to the methodology of Rajneesh Pathak et al, with some modifications. , Two drops of a 5 μM solution of 2,7-DCFH 2 -DA were added to each well, and the plates were incubated for 1 h under refrigeration in the dark.…”

Selection of stain fungi on rubberwood (Hevea brasiliensis) and its growth response against chitosan

“…The addition of chitosan concentration 1 and 5 mg mL -1 in potato dextrose agar (PDA) medium showed 100% inhibition rate, while the diameter colony of control was 20.5 mm after five days incubation. On the other hand, chitosan only gives 40% spore viability of Aspergillus parasiticus, whereas control with 100% spore viability (Hernández-téllez et al 2017).…”