Sulfuric acid

Polycaprolactone diol (PCL diol) with an average molecular weight of 2000 g/mol and a hydroxyl value of 55.67 mg potassium hydroxide (KOH)/g was purchased from the Hunan Juren Chemical New Material Technology Co., Ltd. (Yueyang, China). Hexamethylene diisocyanate (HDI), toluene, and methanol were all purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China). Bleached softwood kraft pulp, containing cellulose (92.1 wt%), hemicellulose (3.6 wt%), lignin (0.2 wt%), and a small amount of ash and moisture, was purchased from Shandong Daoxin New Materials Co., Ltd. (Weifang, China). Sodium-montmorillonite (MMT) with a cation exchange capacity of 90 mmol/100 g was purchased from Zhejiang Fenghong Clay Chemical Co., Ltd. (Huzhou, China). Sulfuric acid (98 wt%) and cetyltrimethylammonium bromide were purchased from Tianjin Damao Chemical Reagent Factory (Tianjin, China). PLA pellets (Ingeo^TM 4032D) with a melt flow index (MFI) of 7 g/10 min (210 °C, 2.16 kg) were purchased from Nature Works LLC (Minneapolis, MI, USA). PCL pellets (Capa^TM 6500) with an MFI of 5.9–7.9 g/10 min (160 °C, 2.16 kg) were purchased from Perstorp UK Ltd. (Malmö, Sweden).

Mulberry leaves (Morus atropurpurea Roxb.) were supplied by the Institute of Sericulture and Agricultural Products Processing, Guangdong Academy of Agricultural Sciences (Guangzhou, China) (specimen accession number is CNCP2009) and picked from the Mulberry Planting Base in Baiyun District, Guangzhou, in June 2019. Mulberry leaf protein (MP) was extracted according to the previous methods described by Sun et al. [21 (link),24 (link)]. An Amicon^® Ultra-15 centrifugal filter, Sephadex^® G-150, and CP were purchased from Sigma-Aldrich (St. Louis, MO, USA). Protein marker and Coomassie Brilliant Blue G-250 were obtained from Sangong Co., Ltd. (Shanghai, China). Mouse IL-2 and IL-6, tumor necrosis factor-α (TNF-α), immunoglobulin A (IgA), and immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) kits were purchased from Neobioscience Technology Co., Ltd. (Shenzhen, China). AR-grade ammonium sulfate, sulfuric acid, NaCl, and NaOH were obtained from Tianjin Damao Chemical Reagent Factory (Tianjin, China). Phenol and Folin phenol reagents were obtained from Maclin Inc. (Shanghai, China). A glycoprotein staining kit was obtained from RealJimes Inc. (Beijing, China).

Beer yeast sludge (containing Saccharomyces cerevisiae) was collected after the fermentation process in Wuchuan Yanjing brewery and further purification or modification, were finished in the laboratory. Real petrochemical wastewater samples were collected from the discharged sewage of Maoming Petrochemical Refining Co., Ltd (Guangdong, China). The other chemicals in this study were consumed as provided by suppliers without any further modifications. Formaldehyde, anhydrous ethanol, polyethylene glycol (molar mass: 600), K₂Cr₂O₇, 1,5-diphenyl carbazide, FeCl₃·6H₂O and FeCl₂·4H₂O were purchased from Shanghai McLean Biochemical Technology Co., Ltd. (Shanghai, China). Hydrochloric acid, sulfuric acid, sodium hydroxide and ammonia water were provided by Tianjin Damao Chemical Reagent Co., Ltd. (Tianjin, China).

Activated carbon and mesoporous carbon powder were purchased from Suzhou Tan-Feng science and technology Co., Ltd. (Suzhou, China), and further purification or modification were performed in the laboratory. Real petrochemical wastewater samples were collected from the discharged sewage of Maoming petrochemical refining Co., Ltd. (Maoming, China).
The other chemicals in this study were consumed as provided by suppliers, without any further modifications. (NH₄)₂FeSO₄·6H₂O, polyethylene glycol, K₂Cr₂O₇, FeCl₃·6H₂O, 1,5-diphenyl carbazide, and FeCl₂·4H₂O were purchased from Shanghai McLean Biochemical Technology Co., Ltd. (Shanghai, China). Hydrochloric acid, acetic acid, sulfuric acid, ethanol, sodium hydroxide, and ammonia were provided by Tianjin Damao Chemical Reagent Co., Ltd. (Tianjin, China).