Antioxidative activity of Mungoong, an extract paste, from the cephalothorax of white shrimp (Litopenaeus vannamei)

The antioxidative activity of Mungoong, an extract paste, from the cephalothorax of white shrimp (Litopenaeus vannamei) was studied. Extraction media were shown to affect the antioxidative activity and properties of resulting extracts from Mungoong. Distilled water exhibited the highest efficacy in extracting the antioxidants from Mungoong, as evidenced by the highest ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picryl hydrazyl) radical scavenging activity as well as ferric reducing activity power (FRAP), compared with distilled water/ethanol mixture (1:1, 1:2 and 2:1) and ethanol. UV-absorbances at both 280 and 295 nm (A280, A295), browning intensity (A420) and fluorescence intensity were also highest in the extract using distilled water. ABTS and DPPH radical scavenging activity and FRAP of water extract, increased linearly with increasing concentration. Good correlation between ABTS and DPPH radical scavenging activity; DPPH radical scavenging activity and FRAP; ABTS radical scavenging activity and FRAP were observed, suggesting that antioxidants in the extract, possessed the capability of scavenging the radicals together with reducing power. Antioxidants in the water extract from Mungoong showed high stability over the wide pH ranges (2–11) and temperature up to 100 °C, in which the activity of more than 80% remained. MALDI-TOF analysis revealed that water extract contained the peptides having the mass ranges of m/z 400–1000 and 4000–7000.