Production and characterization of chitosan obtained from Rhizopus oryzae grown on potato chip processing waste

Abstract

Potato chip processing waste of trimmed potato, potato peel and substandard (low-quality) potato chips, obtained from a potato chip processing plant, were used as substrates for chitosan production from Rhizopus oryzae. It was cultured on each waste product at 30 ± 2°C and 70% moisture content for 21 days. Fermented potato peel had the highest yield after 5 days of fermentation. The cultivation condition of chitosan obtained from R. oryzae was optimum for a peel size of less than 6 mesh, 70% moisture content and a pH of 5. Furthermore, the best extraction condition was using 46% sodium hydroxide at 46°C for 13 h followed by 2% acetic acid at 95°C for 8 h. The maximum chitosan yield obtained by these conditions was 10.8 g/kg substrate. Fungal chitosan properties were found to be 86-90% degree of deacetylation, molecular weight of 80-128 kDa and viscosity of 3.1-6.1 mPa s. Therefore, potato peel could be applied as a low cost substrate for chitosan production from R. oryzae.

Direct Solid-State Fermentation of Soybean Processing Residues for the Production of Fungal Chitosan by Mucor rouxii

“…The fungal cells need an appropriate level of water in which to exercise the various biochemical reactions for the enzymatic breakdown and uptake of the biomass substrate. The results in this study indicated that M. rouxii ATCC 24905 was able to tolerate a lower substrate moisture content of 50% for growth and chitosan production in SS unlike other fungal strains previously studied for chitosan production via SSF, that were grown in 60% -70% moisture substrates [12] [22] [26]. Using less water to moisten the soybean meal substrate could mean less dilution of nutrients and growth factors due to water addition in the culture.…”

“…Fungal chitosan produced in the soybean residue cultures was extracted and isolated using an approach based on previously published methods [12] [22] [23]. The entire contents of each petri dish soy residues culture were processed first by extraction of residual proteins and other alkali soluble materials with NaOH solution with the desired concentration (1 M or 46% w/v) and volume-to-solids ratio (30:1 or 10:1, mL/g dry mass).…”

“…SSF methods have been applied previously for the production of fungal chitosan using a variety of agro-industrial residues and fungal strains, though not as prevalent as using submerged liquid fermentation (SLF) cultures. Potato chip processing wastes [12], cottonseed hulls and corn residues [13], sweet potato [14], and residues from the manufacture of soymilk and mungbean noodles [15] were utilized as fermentation substrates for growth and chitosan production of various filamentous fungal strains. The filamentous fungus Mucor rouxii, a Zygomycete strain, has been well known to produce high amounts of chitosan using SLF [8] [16] [17].…”

Chitinous polymers: extraction from fungal sources, characterization and processing towards value‐added applications

“…Moreover, in order to reduce production costs, it has also been investigated the use of industrial residues as carbon source for fungi cultivation. It was reported in the literature the use of diverse agrofood by-products, namely glycerol from the biodiesel industry, 16 sugar cane molasses, 1 potato chip processing wastes 38 and yam bean wastes. 39 Many reports conclude that solid state fermentation is more efficient than submerged fermentation in fungal biomass production.…”

Processing, Valorization and Application of Bio-Waste Derived Compounds from Potato, Tomato, Olive and Cereals: A Review

“…For example, potato wastes from the potato chip processing (rotten and substandard potato tubers, potato peel and substandard potato chips) were applied for the production of chitosan by fermentation with Rhizopus oryzae [115]. Enriched potato wastes from potato flakes processing (without pretreatment) were also found to be a good nutrient source for the production of glucoamylase by several strains of Aspergillus niger [116].…”