Fecl3

Folin's reaction solution, sodium carbonate, 2,4,6-tripyridyltriazine (TPTZ), 2′-azino-bis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), potassium persulfate, quercetin, trolox, gallic acid, FeCl₃, sodium acetate, and AlCl₃ were from Macklin Biochemical Co., Ltd. (Shanghai, China). Methanol and acetonitrile were purchased from Thermo Fisher Scientific (MA, USA), and formic acid was purchased from Aladdin Biochemical Technology Co., Ltd. (Shanghai, China). Distilled water was obtained from a distilled water machine (EPED-E1-10TJ).
S. involucratus (King ex Bak.) Craib was collected from Yangshan County, Qingyuan City, Guangdong Province, China.

The bacterial strain Pseudomonasputida MnB1 [American Type Culture Collection (ATCC) no. 23483] was cultured in the Lept medium (0.5 g/L yeast extract (Ruji, Shanghai, China), 0.5 g/L Casamino Acids (Coolaber, Beijing, China), 5 mM D(+)-glucose (Macklin, Shanghai, China), 10 mM HEPES (N-2-hydroxyethylpiperazine-N’-2-ethanesulfonic acid, pH 7.5, GBCBIO, Guangzhou, China), 0.48 mM CaC1₂ (Macklin), 0.83 mM MgSO₄ (Macklin), 3.7 μM FeCl₃ (Macklin), and 1 mL of trace element solution (10 mg/L CuSO₄•5H₂O, 44 mg/L ZnSO₄•7H₂O, 20 mg CoCl₂•6H₂O and 13 mg/L Na₂MoO₄•2H₂O, (Macklin)) containing 1mM MnCl₂ (Aladdin, Shanghai, China) at 30 °C and shaken at 150 rpm for 5 d [48 (link)]. The suspensions were centrifuged at 8000× g for 20 m and the supernatant was discarded, sediments of bacteria and BMO were diluted three times with deionized water by means of centrifugation (20 m at 8000× g), then the mixture of precipitates were collected for freeze-drying to obtain the dried BMO sample.

CBD (98%, HPLC purity) was purchased from Guilin Layn Natural Ingredients Corp., Guangxi, China. Olivetol (98%, HPLC purity) was purchased from Shenghong Corporation, Shanghai, China. α-Phellandrene (85%, HPLC purity) was purchased from Sigma-Aldrich, Shanghai, China. BF₃·2H₂O (AR, 99%), CuCl₂·2H₂O (AR, 97%), AlCl₃ (AR, 99%), and FeCl₃ (AR, 98%) were purchased from Macklin Biochemical Co., Ltd., Shanghai, China. All other chemicals were purchased from Sinopharm Chemical Reagent Co., Ltd., Shanghai, China. All the chemicals were of analytical grade and used as received unless otherwise stated.
Escherichia coli (CICC 20549) and Staphylococcus aureus (CICC 23656) strains were supplied by the China Center of Industrial Culture Collection (CICC), Beijing, China. Tetracycline hydrochloride, gentamicin, chloramphenicol, and ofloxacin were obtained from Sinopharm Chemical Reagent Co., Ltd., Shanghai, China.