Utilization of Marine Waste to Obtain β-Chitin Nanofibers and Films from Giant Humboldt Squid Dosidicus gigas

Abstract

β-chitin was isolated from marine waste, giant Humboldt squid Dosidicus gigas, and further converted to nanofibers by use of a collider machine under acidic conditions (pH 3). The FTIR, TGA, and NMR analysis confirmed the efficient extraction of β-chitin. The SEM, TEM, and XRD characterization results verified that β-chitin crystalline structure were maintained after mechanical treatment. The mean particle size of β-chitin nanofibers was in the range between 10 and 15 nm, according to the TEM analysis. In addition, the β-chitin nanofibers were converted into films by the simple solvent-casting and drying process at 60 °C. The obtained films had high lightness, which was evidenced by the CIELAB color test. Moreover, the films showed the medium swelling degree (250–290%) in aqueous solutions of different pH and good mechanical resistance in the range between 4 and 17 MPa, depending on film thickness. The results obtained in this work show that marine waste can be efficiently converted to biomaterial by use of mild extractive conditions and simple mechanical treatment, offering great potential for the future development of sustainable multifunctional materials for various industrial applications such as food packaging, agriculture, and/or wound dressing.

Preparation of Nanochitin from Crickets and Comparison with That from Crab Shells

“…The signals corresponding to C3 and C5 are clearly split at 76 and 74 ppm, suggesting that this is a-type chitin. On the other hand, b-type chitin is known to overlap those signals [23]. These results support the isolation of chitin from crickets.…”

“…The peak of amide I was split, confirming that it is a-type chitin as well as chitin from crab shells. In β-chitin, on the other hand, it is known to appear as a single peak [23].…”

Bioactive Pectin-Murta (Ugni molinae T.) Seed Extract Films Reinforced with Chitin Fibers

“…Further, the addition of chitin nanofibers into pectin and pectin/murta seed extract films resulted in an enhanced water vapor barrier of films. This result is expected, since it is known that fibers with high aspect ratios enhance the barrier property due to the formation of tortuous paths once they are properly and sufficiently dispersed in the polymer matrix [18]. The best WVP barrier was achieved for sample P5, which contains 50% of chitin fibers, reaching a value of 1.12 10 −11 g/m s Pa, which is better in comparison to the control pectin film (P1).…”

“…Citrus pectin (galacturonic acid content 74.3%, degree of methylation 63% mol, Mw 615 kDa) and glycerol were purchased from Sigma-Aldrich and used without further purification. According to the procedure reported in our previous paper, an aqueous dispersion of chitin nanofibers was produced in the lab [18]. The murta (Ugni molinae T.) seed polyphenolic extract was obtained and characterized according to our previous work [5].…”

Optimization and Characterization of a Novel Exopolysaccharide from Bacillus haynesii CamB6 for Food Applications

“…The band at 2926 cm −1 belongs to the (ν-C-H) stretching vibration in the sugar ring [ 42 ]. The absorption band at 1642 cm −1 is due to the stretching vibration (ν C=O, Amide I) [ 43 ]. The Amide I band and that at 1725 cm −1 (ν C=O, COOH/-COCH 3 ), and 1547 cm −1 (ν-C-N (C-N-H) + δNH, Amide II), suggest the presence of protein traces in the EPS [ 44 ], as previously revealed by the elemental analysis.…”