Fermentative Production of Mycelial Chitosan from Zygomycetes: Media Optimization and Physico-Chemical Characterization

Abstract

The present study focused on production of mycelial chitosan from fungal mycelium by submerged fermentation with ecologically more balanced process. Different fungal strains were screened and Absidia butleri NCIM 977 was found to produce the highest mycelial chitosan. The one-factor-at-a-time method was adopted to investigate the effect of batch time, environmental factors (i.e. initial pH and temperature) and medium components (i.e. carbon and nitrogen) on the yield of mycelial chitosan. Among these variables, the optimal condition to increase in yield of mycelial chitosan was found to be batch time (72 h), pH (5.5), temperature (30˚C), carbon source (glucose) and nitrogen source (tryptone and yeast extract). Subsequently, a three-level Box-Behnken factorial design was employed combining with response surface methodology (RSM) to maximise yield of mycelial chitosan by determining optimal concentrations and investigating the interactive effects of the most significant media components (i.e. carbon and nitrogen sources). The optimum value of parameters obtained through RSM was glucose (1.58%), tryptone (1.61%) and yeast extract (1.11%). There was an increase in mycelial chitosan yield after media optimization by one-factor-at-a-time and statistical analysis from 683 mg/L to 1 g/L. Mycelial chitosan was characterized for total glucosamine content (80.68%), degree of deacetylation (DD) (79.89%), molecular weight (8.07 × 10 4 Da) and, viscosity (73.22 ml/g). The results of this study demonstrated that fungi are promising alternative sources of chitosan with high DD and high purity.

Microbial Extraction of Chitin and Chitosan From Pleurotus Spp, Its Characterization and Antimicrobial Activity

“…Florida (201.3 mg/g) followed by the P. eous (145.65 mg/g). [20] produced chitosan from Rhizopusoryzae PAS 17 in low-cost non-sterile conditions revealed the increment of chitosan and biomass yields of 14.45 and 8.58 folds from its an optimised condition, respectively [14]. Used different Zygomycetes for the production of mycelial chitosan and Absidiabutleri NCIM 977 was found to produce the highest mycelial chitosan which is identical to our investigation.…”

“…and Ganoderma Spp. [14]. Produced chitosan from fungal mycelium by submerged fermentation with the ecologically more balanced process.…”

Biotechnological Strategies for Chitosan Production by Mucoralean Strains and Dimorphism Using Renewable Substrates

“…Commercial chitosan is derived from the deacetylation of chitin from crustacean residues, where the process requires a strong alkaline treatment with high temperature due to the complex organization of chitin with other components in the exoskeleton crustacean, and is a slow process with a high cost, causing environmental pollution due to chemical treatments [6]. In addition, this raw material is seasonally and geographically limited and has highly variable characteristics, which may interfere with product yield and molecular product characteristics [5].…”

“…Filamentous fungi, mainly Mucoromycota, formerly belonging to a polyphiletic phylum Zigomycota [7], are known to synthesize natural chitosan in their cell wall, produced by enzymatic deacetylation of the chitin chain, a modification of sugar chains [6,[8][9][10][11][12][13][14].…”

Comparison of Rheological, Drug Release, and Mucoadhesive Characteristics upon Storage between Hydrogels with Unmodified or Beta-Glycerophosphate-Crosslinked Chitosan

“…CS is commercially possessed by deacetylation of chitin derived mainly from the exoskeleton of crustaceans, though alternative production methods by fungal fermentation have been also explored to provide CS with more defined characteristics [8]. Due to polycationic behavior, CS structure can be certainly modified and utilized into diverse semisolid or solid vehicles.…”