Abstract
Microbiological processes were used for chitin and chitosan production with Cunninghamella elegans UCP/WFCC 0542 grown in different concentrations of two agro-industrial wastes, corn steep liquor (CSL) and cassava wastewater (CW) established using a 22 full factorial design. The polysaccharides were extracted by alkali-acid treatment and characterized by infrared spectroscopy, viscosity, thermal analysis, elemental analysis, scanning electron microscopy and X-ray diffraction. The cytotoxicity of chitosan was evaluated for signs of vascular change on the chorioallantoic membrane of chicken eggs. The highest biomass (9.93 g/L) was obtained in trial 3 (5% CW, 8% CSL), the greatest chitin and chitosan yields were 89.39 mg/g and 57.82 mg/g, respectively, and both were obtained in trial 2 (10% CW, 4% CSL). Chitin and chitosan showed a degree of deacetylation of 40.98% and 88.24%, and a crystalline index of 35.80% and 23.82%, respectively, and chitosan showed low molecular weight (LMW 5.2 × 103 Da). Chitin and chitosan can be considered non-irritating, due to the fact they do not promote vascular change. It was demonstrated that CSL and CW are effective renewable agroindustrial alternative substrates for the production of chitin and chitosan.
Highlights
In recent years, there has been an increasing interest in biopolymers, specially chitin and chitosan, due to the fact they are easy to obtain, their wide applicability and their promising features such as their absence of toxicity, biodegradability, biocompatibility and environmentally friendly nature and their wide range of potential industrial applications [1]
The increase of corn steep liquor (CSL) percentage provided a higher yield of biomass and the opposite was observed when the percentage of cassava wastewater (CW) was increased. The interaction between these factors had a negative effect on biomass production, but not a statistically significant one. These results suggest that, in future research, the biomass production of C. elegans could be increased in a culture media with higher CSL
Molecular weight (29.7 and 287.2 cP, respectively). These results were similar to those reported by Pochanavanich and Suntornsuck [10] who stated that the viscosity of fungal chitosan between 3.1 cP to 6.2 cP and commercial crab shell chitosan (Sigma) was 372.7 cP
Summary
There has been an increasing interest in biopolymers, specially chitin and chitosan, due to the fact they are easy to obtain, their wide applicability and their promising features such as their absence of toxicity, biodegradability, biocompatibility and environmentally friendly nature and their wide range of potential industrial applications [1]. Chitin is commercially obtained from the exoskeletons of marine crustaceans, and chitosan by alkaline deacetylation of chitin at high temperatures for long periods of time [11] These traditional isolation methods of these polymers present some drawbacks and limited potential for industrial acceptance such as the seasonal and limited supply of the raw material while the process of demineralization and deproteinization is aggressive and causes changes in the final product, thereby often lowering its quality since this can cause chemical changes. In addition to obtaining microbiological chitin and chitosan with homogenous characteristics and more consistent quality, the biopolymer yields may be optimized by controlling fermentation and processing parameters such as pH, nutrient concentration in the fermentation medium and the length of incubation time [3,14] The extraction of these biopolymers is simultaneous; independent of seasonal factors; and the final products do not have the protein contamination that can cause allergic reactions in humans [2,4]. The physicochemical characteristics and cytotoxicity of the synthesized chitin and chitosan are described
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
