Feso4

In 2022, Luffa leaf (LL) was obtained from the experimental area of Jilin Agricultural University (Changchun, China), washed, dried, and crushed. NaOH, HCl, KOH, FeSO₄, and FeCl₃ were purchased from Beijing Chemical Works (Beijing, China) and used without further purification. RhB (CAS: 81-88-9, ≥95%) and TH (CAS: 64-75-5, 96%) were supplied by Aladdin Chemical (Shanghai) Co., Ltd. (Shanghai, China), and the structural formulas are shown in Figure S1 (Supplementary Material).

Irisensata Thunb grass (ITG) was obtained from the experimental area of Jilin Agricultural University (Changchun, China) in 2022, washed with deionized water, dried at 80 °C for 12 h, and crushed. Aspergillus niger (A. niger) was supported by the Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education.
D-glucose monohydrate and agar were provided by Sinopharm Chemical Reagents Co., Ltd. (Shanghai, China). Potatoes were bought from a local supermarket. (NH₄)₂SO₄, KH₂PO₄, MgSO₄, CaCl₂, NaCl, FeSO₄, MnSO₄, ZnCl₂, NaOH, HCl, and KOH were purchased from Beijing Chemical Works (Beijing, China) and used without further purification. Mixed base (MB) was prepared by using equal masses of NaOH and KOH.
Rhodamine B (RhB, CAS: 81−88−9) and Tetracycline hydrochloride (TH, CAS: 64−75−5) were supplied by Aladdin Chemical (Shanghai) Co. Ltd. (Shanghai, China) and the structural formulas of RhB and TH are shown as Figure S1 (Supplementary Material).