Search

Biological waste from marine sources is discarded into various water bodies which leads to dramatic increase in the water pollution near coastal areas. This animal waste consists of bioactive compo...

The antioxidant activity of protein hydrolysates prepared from the skin of Sphyraena barracuda (Seela fish) and Lepturacanthus savala (Ribbon fish), using the commercial enzymes pepsin, trypsin, and papain were determined. The protein hydrolysate showed high antioxidant activity in which trypsin hydrolysate of the skin of both seela and ribbon fish proved good DPPH scavenging activity with 66 and 60% (p < 0.05), respectively. These active hydrolysates were purified using fast protein liquid chromatography on ion exchange and gel filtration chromatography procedure and the active purified fractions were determined using electron spin resonance spectrophotometer against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. Further the purified fractions were analyzed for amino acid composition using high performance liquid chromatography and it consisted of antioxidant inducing amino acids along with a considerable quantity of essential amino acids.

Acid and pepsin-soluble collagen was isolated from the skin of horse mackerel (Magalaspis cordyla) and croaker (Otolithes ruber) using 0.5 M acetic acid followed by precipitation with 0.9 M NaCl. The yields of acid soluble collagen were 17.3 ± 0.4 and 21.9 ± 0.6% and pepsin soluble collagen (22.5 ± 0.8 and 25.7 ± 0.3%) as per wet weight basis, respectively. The extracted acid soluble collagen and pepsin soluble collagen were characterized by SDS-PAGE, amino acid composition and FTIR spectroscopy. SDS-PAGE showed that all the extracted collagen contained two alpha components (α 1 and α 2) and one beta component (β); all the collagens were typical type I and maintained their triple helical structures well with slight molecular structure differences. The amino acid profiles of these collagens were similar with a low imino acid content. Therefore, there is a possibility to use horse mackerel and croaker skin collagen as an alternative source for commercial collagen and may find applications in the food, cosme...

In the present study, bioactive peptide was isolated from protein hydrolysate of Nemipterus japonicus backbone hydrolysed by trypsin. Functional properties like solubility, emulsifying, and foaming capacities of protein hydrolysate were governed by pH. Protein hydrolysate was fractionated by DEAE XK 26/20 anion exchange chromatography followed by G-25 gel filtration chromatography. The fractions collected were tested for radical scavenging properties on DPPH, hydroxyl, and superoxide radicals by electron spin resonance spectrometer. Amino acid composition of a potent fraction was rich in glutamic acid (21.20 g/100 g), lysine (37.50 g/100 g), aspartic acid (5.8 g/100 g), arginine (5.4 g/100 g), and glycine (2.84 g/100 g). Moreover, the potent fraction showed no cytotoxicity on Vero cell lines till 0–100 μg/ml with CC50 = 94 μg/ml, whereas it exerted a significant antitumor property against HepG2 cell line with an IC50 value of 61.1 μg/ml.

The focus of the study was to investigate the antioxidant activity of hydrolyzed muscle protein of Nemipterus japonicus and Exocoetus volitans. The trypsin protein hydrolysates of both fish showed maximum free radical scavenging potential and lipid peroxidation inhibition. Furthermore, it was purified by chromatographic methods followed by the lipid peroxidation inhibition; free radical scavenging assay was performed before and after purification. The purified peptide fractions of N. japonicus and E. volitans exhibited higher activity against polyunsaturated fatty acids (PUFA) peroxidation which was similar to natural antioxidants like α-tocopherol. Free radical scavenging potencies were measured by electron spin resonance technique (ESR). The purified peptide of E. volitans quenched free radicals (DPPH, hydroxyl, and superoxide) slightly more than N. japonicus. The amino acid composition of both fish protein hydrolysates showed variations in their ratio. The purified peptides were tested for cell cytotox...