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In this study, Phellodendron chinense powder (40 g) was extracted by using 1 L diethyl ether in nitrogen atmosphere for 2 hours under reflux. Then, the supernatant was collected and evaporated to dry in rotary evaporators to obtain the diethyl ether extract, named Phellodendron phosphor. Figure 1(a) shows the schematic of the extracted device for Phellodendron phosphor. Phellodendron chinense powder was purchased from the Sheng Chang pharmaceutical Co., Ltd. Technology. Diethyl ether (HCOOH, >98%) was purchased from Sigma-Aldrich (USA). For the W-LED fabrication, 0.1 g phosphor were mixed with 0.1 g thermal-curable silicone resin (OE-6636A) under vigorous stirring. Subsequently, silicone resin (OE-6551B, 0.1 g) was added to form a paste. The procedure of LED packing by LED dispenser is shown in Fig. S1. W-LEDs were fabricated by dispensing the phosphor containing paste onto the InGaN-based blue-LED chip (ES-CEBLV10R). In this paper, W-LEDs device we used could be divided into three types: LED (1): Blue chip (455~460 nm)  + YAG (0.1 g, UC-521B); LED (2): Blue chip (455~460 nm)  + YAG phosphor (0.1 g, UC-521B) + Phellodendron phosphor (0.01 g) and LED (3): Blue chip (455~460 nm) + YAG phosphor (0.1 g, UC-521B) + CaAlSiN₃:Eu²⁺ phosphor (0.00475 g, CN-NR630). Figure 1(b) exhibits the illustration of w-LEDs packaged for LEDs and all conditions were packaged with 15 iterations each.

H₂SO₄, HCl, NaNO₃ (Chempur), KCl (Sigma-Aldrich), NaOH (Fluka), and HCOOH (Sigma-Aldrich) were obtained. NaH₂PO₄ (Sigma) and Na₂HPO₄ (POCh) were used for aqueous electrolyte preparation with deionized water purified by using an Elix system (Millipore). Argon N5.0 was from Multax.

The reference substances 1H-pyrrole-2,4-dicarboxylic acid (PDCA) and 1H-pyrrole-2,4,5-tricarboxylic acid (PTCA) were purchased from Fluorochem (Hadfield, UK). K₂CO₃, Na₂SO₃, HCl and H₂O₂ (30%) were purchased from Carl Roth GmbH + Co. KG (Karlsruhe, Germany), and resazurin sodium salt was purchased from Alfa Aesar (Haverhill, MA, USA). HCOOH, 3-isobutyl-1-methylxanthine (IBMX) and synthetic melanin were purchased from Sigma-Aldrich Chemie GmbH (Munich, Germany); MeOH and water (MS-grade) were obtained from VWR International (Radnor, PA, USA). All substances were stored at appropriate temperatures and conditions. All solutions were prepared with deionized water unless stated otherwise.

For HPLC-HRMS analyses, H₂O was purified with a Barnstead EASYpure RF compact ultrapure water system, and CH₃OH (VWR International, Rosny-sous-Bois-cedex, France) and HCOOH (Sigma Aldrich, Steinheim, Germany) were LC-MS grade. The other solvents were of analytical grade. Amentoflavone, luteolin and luteolin-7-glucoside were purchased from Carl Roth (Karlsruhe, Germany). Apigenin and pheophorbide A were purchased from Sigma Aldrich (Steinheim, Germany), and podocarpusflavone A, from Carbosynth (Berkshire, UK). Silica gel 60 for VLC (particle size 0.040–0.063 mm) and LiChroprep^® RP-18 (0.040–0.063 mm) for RP-18 column chromatography were purchased from Merck (Darmstadt, Germany). For solid-phase extraction, 5 g or 10 g Isolute^® C18 (EC) cartridges (Biotage, Uppsala, Sweden) were used.

Madder roots (Rubia tinctorum L.) and alum (KAl(SO₄)₂) were purchased from “Chroma” srl. Genuine indigo in pieces (Indigofera Tinctoria), rabbit skin glue, and CaSO₄ were purchased from Kremer Pigmente (Germany). Bricks were purchased from “Mattone Romano” srl (Italy). KC₄H₅O₆ was purchased from a grocery shop. Turmeric was purchased from Chroma. Agar in powder (ash 2.0–2.4%), solvents, and salts, such as ammonia (30–33%), NaCO₃ (≥99.0%), Na₂S₂O₄ (≥82.5%), K₂CO₃ (with impurities ≤55.0 ppm), NaOH (≥95%), hydroxylamine hydrochloride (99.9%), NaCl (with impurities ≤0.005% as insoluble matter), Na₂EDTA (with impurities ≤0.005% as insoluble matter), silver nitrate (≥99.0%), HCl (37%), HCOOH (≥95%), 2-propanol, and 1-pentanol, were purchased from Sigma-Aldrich. Nanorestore Gel^® High Water Retention was purchased from CSGI (Center for Colloid and Surface Science).