| Autor: |
Wong ZCF; Shenzhen Key Laboratory of Edible & Medicinal Bioresources , Hi-Tech Park , Nanshan, Shenzhen 518057 , China.; Division of Life Science and Center for Chinese Medicine R&D , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR , China., Chan GKL; Shenzhen Key Laboratory of Edible & Medicinal Bioresources , Hi-Tech Park , Nanshan, Shenzhen 518057 , China.; Division of Life Science and Center for Chinese Medicine R&D , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR , China., Dong TTX; Shenzhen Key Laboratory of Edible & Medicinal Bioresources , Hi-Tech Park , Nanshan, Shenzhen 518057 , China.; Division of Life Science and Center for Chinese Medicine R&D , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR , China., Tsim KWK; Shenzhen Key Laboratory of Edible & Medicinal Bioresources , Hi-Tech Park , Nanshan, Shenzhen 518057 , China.; Division of Life Science and Center for Chinese Medicine R&D , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR , China. |
| Abstrakt: |
The red color of edible bird's nests (EBNs) has remained a mystery for hundreds of years. Here, different analytical methods were employed to identify the color origin of EBNs. The treatment of white EBNs with NaNO 2 /HCl turned them red. In a simulated-gastric-fluid (SGF)-digested EBN, the HPLC chromatogram, NMR spectrum, circular-dichroism spectrum, and Raman spectrum of a NaNO 2 -treated white EBN closely resembled those of an authentic red EBN. From the HPLC chromatogram of the SGF-digested EBN, the peptides associated with red color were identified in a red EBN and NaNO 2 -treated white EBN. Several lines of evidence indicated that the color-containing peptide could be derived from the acidic mammalian chitinase-like (AMCase-like) protein of EBNs. Additionally, there was a noticeable increase in Fe-O-bonding intensity after the color change. On the basis of the findings, we proposed that the oxidation of Fe ions in AMCase-like proteins contributed significantly to the color change of EBNs. |
