Extraction of bioactive compounds from black‐footed abalone (Haliotis iris) using subcritical water extraction

BACKGROUND Owing to their biodiversity, many valuable natural compounds have been extracted from marine resources and used in the development of pharmaceutical, nutraceutical and cosmeceutical products. The New Zealand black‐footed abalone (Haliotis iris) is known to host a variety of bioactive compounds in its flesh. RESULTS Water‐soluble bioactive compounds were extracted from H. iris by subcritical water extraction technique, and the effect of subcritical water temperature (110–280 °C) on the extraction performance was studied. The highest antioxidant activity and subsequently glycogen and phenolic content, as well as concentration of bioactives, were found at temperatures between 220 and 250 °C. The carbohydrate content of the extracts peaked at 110 °C, which was then degraded at higher temperatures. Protein and amino acid contents of H. iris extracts were also decreased as the temperature increased above 160 °C. Furthermore, the H. iris extracts were found to be non‐toxic. CONCLUSION The results indicate that extraction temperature has a significant impact on the bioactivity of H. iris extracts. Subcritical water extraction can be used in place of more traditional techniques to create high‐quality abalone extracts.