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Carbon materials derived from marine waste have been drawing attention for supercapacitor applications. In this work, chitins from squid and prawn marine wastes were used as carbon precursors for further application as electrodes for energy storage devices. Chitins were obtained through a deproteinization method based on enzymatic hydrolysis as an alternative to chemical hydrolysis as commonly presented in the literature. The obtained porous carbons were characterized using a BET surface area analyzer to determine the specific surface area and pore size, as well as scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), Raman spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), to characterize their morphology, composition, and structure. The electrochemical characterization was performed using a glassy carbon (GC) electrode modified with marine waste-based porous carbons as the working electrode through cyclic voltammetry and galvanostatic charge/discharge using ethaline, a choline chloride-based deep eutectic solvent (DES), as an eco-friendly and sustainable electrolyte. Squid and prawn chitin-based carbons presented a surface area of 149.3 m2 g−1 and 85.0 m2 g−1, pore volume of 0.053 cm3 g−1 and 0.029 cm3 g−1, and an associated specific capacitance of 20 and 15 F g−1 at 1 A g−1, respectively. Preliminary studies were performed to understand the effect of -OH groups on the chitin-based carbon surface with DES as an electrolyte, as well as the effect of aqueous electrolytes (1 mol L−1 sulphuric acid (H2SO4) and 1 mol L−1 potassium hydroxide (KOH)) on the capacitance and retention of the half-cell set up. It is provided, for the first time, the use of chitin-based carbon materials obtained through a one-step carbonization process combined with an eco-friendly DES electrolyte for potential appli

Crude cartilage powder does not accelerate cellular proliferation in newly established human fetal skin fibroblast cultures at concentrations of 0.3 or 30 microg/ml. Collagen biosynthesis is not increased in confluent cultures of human fetal or adult skin fibroblasts by addition of saline or distilled water extracts of cartilage powder at medium concentrations of 30 or 100 microg/ml. Neither N-acetyl glucosamine nor its polymeric form, chitin, has a consistent stimulatory or inhibitory influence on collagen biosynthesis in confluent cultures at final concentrations of 5.0, 50, or 500 microg/ml. The results are taken as evidence that cartilage powder and its extracts and related compounds to not directly influence collagen production in the tissue culture system. The suggestion is made that perhaps the known effects of cartilage powder on wound tensile strength in vivo are exerted by an indirect mechanism as through provision of a matrix material for collagen aggregation. (Author)

The report summarizes work carried out on the effects of temperature on chitinase activity by chitinoclastic bacteria and in situ activity of chitinoclastic bacteria in model seabed system, together with a general summary of work carried out throughout the entire contract period (1964-1970), which highlights the principal findings and conclusions. (Author)

The biosynthesis of insect rubber-like cuticle was studied by means of autoradiography and electron microscopy, and the structure and development of insect hard cuticle was studied by different types of microscopy and solvent extractability. The results obtained indicate that the insect cuticle together with the epidermal cells constitute a very complex morphogenetic system, where the properties of the final product are very precisely controlled. Proteins can be present both in a crosslinked and an uncross-linked state. Two protein-bound diphenolic compounds have been isolated from hard cuticle, one of them has been identified as arterenone. They may be involved in cross-linking the proteins. Bifunctional amino acids were isolated from a rubber-like protein in molluscs. Measurements of the work and heat changes going on during deformation of elastin indicate that this protein is not rubber-like, but that the elasticity can be due to interaction between hydrophobic groups in the protein and the surrounding matter. Better methods were worked out for the isolation of the spindle apparatus from dividing cells. (Author)