Isolation of chitosan from Ganoderma lucidum mushroom for biomedical applications.

Chitin biopolymer production and its by-product chitosan show great potential. These biomaterials have great applicability in various fields because they are non-toxic, biodegradable, biocompatible, and have antimicrobial effects. The most common source of chitin and chitosan is the crustaceous shell; however, mushrooms are an alternative source for isolating these biopolymers because their cellular wall has a high content of chitin, which may be transformed into chitosan through a deacetylation reaction. The main objective of this research was to obtain chitosan through the deacetylation of chitin isolated from the Ganoderma lucidum basidiomycetes mushroom, which is obtained through biotechnological culture. The material characterization was performed using X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and an evaluation of cytotoxicity comparing the results obtained with results for commercial chitosan. Protocol results showed that chitosan obtained from this mushroom had a significant similitude with commercial chitosan, yet the one obtained using P2 protocol was the one that rendered the best results: including diffractogram peaks, characteristic infrared analysis bands, and an 80.29 % degree of deacetylation. Cytotoxicity in vitro testing showed that the material was non-toxic; furthermore, it rendered very promising information regarding the evaluation of future applications of this biomaterial in the field of biomedicine.

Comparison of extraction methods of chitin from Ganoderma lucidum mushroom obtained in submerged culture.

The chitin was isolated from the Ganoderma lucidum submerged cultures mycelium as potential source of chitin under biotechnological processes. The extraction of chitin was carried out through 5 different assays which involved mainly three phases: pulverization of the mushroom, deproteinization of the mycelia with NaOH solution, and a process of decolorization with potassium permanganate and oxalic acid. The chitin contents extracted from 9-day mycelia were 413, 339, 87, 78, and 144 mg/g(-1) (milligrams of chitin/grams of dry biomass) for A1, A2, A3, A4, and A5, respectively. Obtained chitin was characterized by X-Ray Diffraction (XRD), by Fourier transform infrared spectroscopy (FTIR), and by thermal analysis (TGA). The results showed that Ganoderma lucidum chitin has similar characteristic of chitin from different fonts. The advantage of the biotechnological processes and the fact that Ganoderma lucidum fungus may be used as a potential raw material for chitin production were demonstrated.