Fish-Derived Antifreeze Proteins and Antifreeze Glycoprotein Exhibit a Different Ice-Binding Property with Increasing Concentration

The concentration of a protein is highly related to its biochemical properties, and is a key determinant for its biotechnological applications. Antifreeze proteins (AFPs) and antifreeze glycoproteins (AFGPs) are structurally diverse macromolecules that are capable of binding to embryonic ice crystals below 0 degrees C, making them useful as protectants of ice-block formation. In this study, we examined the maximal solubility of native AFP I-III and AFGP with distilled water, and evaluated concentration dependence of their ice-binding property. Approximately 400 mg/mL (AFP I), 200 mg/mL (AFP II), 100 mg/mL (AFP III), and >1800 mg/mL (AFGP) of the maximal solubility were estimated, and among them AFGP's solubility is much higher compared with that of ordinary proteins, such as serum albumin (similar to 500 mg/mL). The samples also exhibited unexpectedly high thermal hysteresis values (2-3 degrees C) at 50-200 mg/mL. Furthermore, the analysis of fluorescence-based ice plane affinity showed that AFP II binds to multiple ice planes in a concentration-dependent manner, for which an oligomerization mechanism was hypothesized. The difference of concentration dependence between AFPs and AFGPs may provide a new clue to help us understand the ice-binding function of these proteins

Advances of polyolefins from fiber to nanofiber: fabrication and recent applications

Abstract Polyolefins are a widely accepted commodity polymer made from olefinic monomer consisting of carbon and hydrogen. This thermoplastic polymeric material is formed through reactive double bonds of olefins by the addition polymerization technique and it possesses a diverse range of unique features for a large variety of applications. Among the various types, polyethylene and polypropylene are the prominent classes of polyolefins that can be crafted and manipulated into diversified products for numerous applications. Research on polyolefins has boomed tremendously in recent times owing to the abundance of raw materials, low cost, lightweight, high chemical resistance, diverse functionalities, and outstanding physical characteristics. Polyolefins have also evidenced their potentiality as a fiber in micro to nanoscale and emerged as a fascinating material for widespread high-performance use. This review aims to provide an elucidation of the breakthroughs in polyolefins, namely as fibers, filaments, and yarns, and their applications in many domains such as medicine, body armor, and load-bearing industries. Moreover, the development of electrospun polyolefin nanofibers employing cutting-edge techniques and their prospective utilization in filtration, biomedical engineering, protective textiles, and lithium-ion batteries has been illustrated meticulously. Besides, this review delineates the challenges associated with the formation of polyolefin nanofiber using different techniques and critically analyzes overcoming the difficulties in forming functional nanofibers for the innovative field of applications. Graphical abstrac