Synthesis of nano hydroxyapatite from Hypopthalmichthys molitrix (silver carp) bone waste by two different methods: a comparative biophysical and in vitro evaluation on osteoblast MG63 cell lines.

More than a thousand tonnes of fish bone wastes can be transformed into biomedical products annually. Alkaline hydrolysis and thermal calcification were used to create nanosized hydroxyapatite (HAp) crystals from Silver carp bone wastes. Biophysical tests were used to determine the nano size and chemical composition of synthesised hydroxyapatite. Alkaline hydrolysis hydroxyapatite (AH-HAp) was 58.3 nm, while Thermal calcination hydroxyapatite (TC-HAp) was 64.3 nm in size, confirmed by Atomic Force Microscopy. Energy Dispersive X-ray Analysis studies showed Ca/P (Calcium phosphate) ratio of AH-HAp to be 1.65, whereas TC-HAp as 1.45, confirming AH-HAp to be organically rich along with a similar Ca/P ratio as natural HAp. Fourier Transform Infrared Spectroscopy spectra indicated HAp formation from both procedures, however AH-HAp had superior crystallinity than TC-HAp confirmed from X-Ray Diffraction spectra. MG63 osteoblast cell lines showed 91% cell viability in cytotoxicity studies and 70.1% proliferation efficiency in Alkaline Phosphatase assay, which was higher than TC-HAp. The present study shows that HAp produced via alkaline hydrolysis has better biocompatibility which enhances its applicability as a biomaterial, than HAp synthesized through thermal calcination, which tends to incinerate organic moieties.

A comparative assessment of collagen type 1 from silver carp (fresh water) and milk shark(marine) fish waste.

In this study, a comparative structural and bioactive analysis of collagen extracted from the skin of bony and cartilaginous fishes. The acid-soluble method was followed to extract the collagen from Hypophthalmichthys molitrix (silver carp) and Rhizoprionodon acutus (milk shark) followed by purification using Ion exchange chromatography. A higher yield of collagen was obtained from the skin of SCsk (69.45%) as compared to SHsk (55.29%). SDS PAGE displayed the characteristic α, ß bands of the collagen type1. The native conformation and secondary structure stability of collagen were confirmed by FTIR, XRD and CD studies. The SEM micrographs exhibited the layered and fibrillar nature of the collagen from SHsk and SCsk, respectively. Relative solubility and thermal denaturation analysis showed SCsk to be more stable, but SHsk could withstand higher temperatures. 53.65% of antioxidant activity was observed in SCsk collagen as compared to SHsk (45.9%). Haemocompatibility, cell viability and adhesion results also displayed silvercarp skin to be a better source than Shark skin collagen. The results establish the potential of silver carp collagen as a biomaterial that can have many commercial applications in tissue engineering, cosmetics and food industries.