Extraction and characterization of fungal chitin nanofibers from Mucor indicus cultured in optimized medium conditions

• Published in: International journal of biological macromolecules 2021-01, Vol.167, p.1126-1134
• Main Authors: Salehinik, Fatemeh, Behzad, Tayebeh, Zamani, Akram, Bahrami, Bahador
• Format: Article
• Language: English
• Subjects: analysis; Biomass; Chemical Fractionation; Chemical Fractionation - methods; chemistry; chitin; Chitin - chemistry; Chitin - isolation & purification; Chitin nanofiber; chitin nanoparticle; chitosan; Chitosan - chemistry; concentration (parameter); Conditioned; conditioned medium; controlled study; Culture Media; Culture Media - analysis; Culture Media - chemistry; Culture Media, Conditioned - analysis; Culture Media, Conditioned - chemistry; culture medium; deacetylation; decolorization; field emission scanning electron microscopy; Fourier Transform Infrared; Fourier transform infrared spectroscopy; fractionation; fungal biomass; fungal cell wall; fungal polysaccharide; Fungal Polysaccharides; Fungal Polysaccharides - chemistry; glucose; high performance liquid chromatography; infrared spectroscopy; isolation and purification; Mucor; Mucor - chemistry; Mucor indicus; n acetylglucosamine; nanofiber; Nanofibers; Nanofibers - chemistry; nonhuman; Optimized cultivation; phosphate; Phosphates; Phosphates - chemistry; procedures; purification; reaction optimization; Resource Recovery; Resursåtervinning; scanning electron microscopy; Spectroscopy; Spectroscopy, Fourier Transform Infrared; X ray diffraction
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2020.11.066

Chitin nanofibers (ChNFs) were extracted from Mucor indicus by a purification method followed by a mechanical treatment, cultivated under obtained optimum culture medium conditions to improve fungal chitin production rate. A semi synthetic media containing 50 g/l glucose was used for cultivation of the fungus in shake flasks. The cell wall analysis showed that N-acetyl glucosamine (GlcNAc) content, which is an indication of chitin content, was maximum in presence of 2.5 g/l H3PO4, 2.5 g/l of NaOH, 1 g/l of yeast extract, 1 mg/l of plant hormones, and 1 ml/l of trace metals. The chemical characterizations demonstrated that the isolated fibers had a degree of deacetylation lower than of 10%, and were phosphate free. The FTIR results revealed successful removal of different materials during the purification step. The FE-SEM of fibrillated chitin illustrated an average diameter of 28 nm. Finally, X-ray diffraction results showed that the crystallinity index of nanofibers was 82%. •The optimization of cultivation conditions for enhancement of the chitin production by M. indicus fungus.•The isolation of chitin fibers from cell wall of the filamentous fungus M. indicus through purification.•The characterization of Fungal chitin nanofibers were isolated by mechanical grinding of fungal chitin.•The chitin nanofibers had an average diameter of 28 nm and the crystallinity index of 82%.