Effect of Gamma rays on nutritive value, and on occurrence of Vibrio alginolyticus in fillets of puffer fish (Logocephalus sceleratus)

Abstract

The effect of Gamma rays on the nutritive value, Vibrio alginolyticus infection and some radioactivity elements of Logocephalus sceleratus fillets were investigated. Puffer fish samples were obtained from El-Anfousy, Alexandria, Egypt, during February and March, 2017. Fish fillets were exposed to 4 and 7 kGy using 60Co, then the nutritive value, histamine content, and Vibrio alginolyticus were determined. The results showed that raw fillets contained 76.69% water content, 17.68% protein, 0.41% lipid, 1.25% ash and 3.97% carbohydrate. The total amino acids was78.93 mg/16 Ng and the histamine level was 2.2365 mg/100 g. The minerals contents (mg/100 g) were 1.660 K, 0.300 Na, 4.087 Ca, 17.905 Mg, 0.778 Fe, 0.222 Zn and 1.149 Cu. Besides, the measurement of NaI Gamma spectrometer was nearly the same for raw and treated fillets. However, the effective doses for 10 and 22 kg were lower than the threshold dose. Although V. alginolyticus was isolated from raw samples, it wasn't detected in treated samples. The isolated strains showed homogenous biochemical patterns and the PCR pointed out specific amplification product of 737 bp for collagenase gene. In conclusion, although puffer fish is a good nutritive source, further studies are necessary to overcome its toxicity. Keywords: Puffer fish, Nutritive value, Vibrio alginolyticus, Gamma rays