Color-specific porosity in double pigmented natural 3d-nanoarchitectures of blue crab shell

Abstract

A) B) Supplementary Figure 1. Photographs of the studied crab shells showing the diversity of color hues and their patterns. Morphological regions from which samples were taken are indicated as blue, red and white areas on Callinectes sapidus (the Atlantic blue crab) claws (A), and green area on Carcinus aestuarii (the Mediterranean green crab) claws (B).

Wasted Biomaterials from Crustaceans as a Compliant Natural Product Regarding Microbiological, Antibacterial Properties and Heavy Metal Content for Reuse in Blue Bioeconomy: A Preliminary Study

“…Shells of the two crab species, the Atlantic blue crab ( Callinectes sapidus ) and the Mediterranean green crab ( Carcinus aestuarii ) [ 4 , 5 ], were considered here. Crab specimens are caught periodically for the purpose of collaborative experiments between the Babeș-Bolyai University and the University of Dubrovnik, in Parilla lagoon (Neretva river delta), which is historically an agricultural and industrial region of Croatia and Bosnia and Herzegovina, respectively.…”

“…This study did not require formal institutional ethical approval; however, specimens were handled according to the best available animal welfare in science practices and institutional ethical recommendations [ 4 , 5 , 6 ].…”

“…For decades, it has been known that marine organisms, especially the crustacean shells, are a reservoir of still insufficiently exploited or resources [ 1 , 2 ]. Crab shells are a known source of chitin [ 1 ]; however, the utilization of the shell biocomposite as a whole has only recently been a subject of deeper technological investigations [ 3 , 4 , 5 , 6 ]. The safe and sustainable use of crabs in agrotechnology requires a knowledge-based approach and insights into which chemical or microbiological parameters are critical to avoid potential environmental pollution or crop under-performance.…”

“…The color-specific porosity of the blue crab (species Callinectes sapidus , native to North America, invasive in the Mediterranean) and the green crab (species Carcinus aestuarii, native to the Mediterranean) shells has been recently comprehensively investigated by multiple techniques [ 4 , 5 ]. Spectroscopy, diffraction, and thermogravimetry techniques showed that the bulk crab claw shells consist of Mg-calcite (75–85% by weight) mineralized on a chitin-rich organic fibrous scaffold (14–19% by weight), and additionally contain carotenoid pigments and carotenoproteins [ 4 , 5 ]. This unique combination of bioactive organic compounds, carbonate minerals, and nanoporosity makes crab shells an attractive complex natural product for various niches of agricultural applications or other smart biocomposites for wider applicability, as previously described [ 4 ].…”

“…Here, based on our previous reported structural and biochemical data on crab shells [ 4 , 5 ], we investigated the microbiology properties of the shell powder and its potential heavy metal accumulation. Such information is crucial for further utilization of the respective biogenic powders for any added-value by-products.…”