Uv 8000 spectrophotometer

The absorbance of filtered samples with 20 times dilution was determined by a Metash UV-8000 Spectrophotometer (Shanghai, China) with the detector λ = 429 nm using a standard quartz cuvette (1 cm of the optic path). The percentage of color removal was calculated as follows: $$\mathrm{Color}\mathrm{Removal}=\frac{A_0-A}{A_0}\times 100$$
The electrogenerated H₂O₂ was determined by a standard spectrophotometric method detecting the absorbance of yellowish Ti (Ⅳ) complex using a Metash UV-8000 Spectrophotometer (Shanghai, China) with the detector λ = 408 nm.

Optical rotations were measured on a Jasco P-1010 polarimeter. The ultraviolet (UV) absorption spectra were measured in MeOH on a METASH UV-8000 spectrophotometer. The infrared (IR) spectra were recorded using a Bruker Vector 22 spectrometer (film) and an Avatar 370 Fourier-transform–infrared (FT–IR) spectrometer (KBr disk). NMR spectra were recorded in Chloroform-d (ALDRICH, St. Louis, MO, USA) with tetramethylsilane as an internal standard or Pyridine-d₅ (ALDRICH, St. Louis, MO, USA), using a Bruker AVANCE-III 500 MHz NMR spectrometer (Brucker, Ettlingen, Germany). HR-ESIMS data were obtained on an Agilent 6224 TOF LC/MS (Agilent, Santa Clara, CA, USA) (positive mode; infusion rate: 0.6 mL/min; capillary voltages: 4000 V; nebulizer: 50 psig; drying gas: 10mL/min; gas temperature: 325 °C).
Column chromatography (CC) was performed with silica (100–200 and 200–300 mesh, Qingdao Haiyang Chemical Co., Ltd., Qingdao, China).

Optical rotations were recorded on a Perkin-Elmer model 341 polarimeter (Perkin-Elmer Inc., Waltham, MA, USA). The UV and CD spectra were recorded on a UV-8000 spectrophotometer (Shanghai Metash instruments Co., Ltd., Shanghai, China) and a Jasco J-715 spectropolarimeter in MeOH (JASCO, Tokyo, Japan), respectively. The IR spectra were obtained on a VERTEX 70v FT-IR spectrometer (Bruker Biospin Corp., Billerica, MA, USA). The NMR experiments were conducted on a Bruker AMX-500 instrument (Bruker Biospin Corp., Billerica, MA, USA). HRESIMS spectra were recorded on an AB SCIEX Triple Tof-4600 spectrometer (ABSciex, Vaughan ON, Canada). Column chromatographic separations were carried out using silica gel (200–300 mesh, Qingdao Ocean Chemical Co., Ltd., Qingdao, China) and ODS (50 μm, YMC Co., Ltd., Kyoto, Japan). MPLC was carried out on a SepaBean machine (Santai Technology Co., Ltd., Changzhou, China). RP HPLC was performed on a YMC-Pack Pro C18 column (250 × 10 mm, 5 mm, YMC Co., Ltd., Kyoto, Japan) using a Waters 1525 binary HPLC pump with a Waters 2998 photodiode array detector (Waters Corp., Milford, MA, USA). Analytical thin-layer chromatography was performed on silica gel HSGF254 plates and visualized by spraying with anisaldehyde–H₂SO₄ reagent.