FIG 4.

(A to C) EEM spectra in raw samples of Wa-HA (A), Ald-HA (B), and IH-HA (C). (D) Variation of intensities of the peaks seen in the raw samples during the virus concentration process. The values indicate the positions and intensities of the peaks. The EEM spectra are divided into 4 regions, I/II, III, IV, and V. The peaks appearing in regions I/II and IV correspond to protein-like substances, and those in regions III and V correspond to fulvic acid-like and humic acid-like substances, respectively.