Acetic acid

The following starting materials and reagents were used in this study: α-pinene (98%), glycolic acid (98%), D-(-)-lactic acid (90%), citric acid (99.5%), L (+)-tartaric acid (99.5%), DL-mandelic acid (99%), boric acid (98%). These compounds were purchased from Macklin and Aladdin (Shanghai, China). Acetic acid (99.5%), citric acid monohydrate (99.5%), ethyl acetate (99.8%) and sodium hydroxide (98%) were purchased from Chengdu Kelong Chemical (Chengdu, Sichuan Province, China).
The reaction apparatus was an organic synthesis unit PPV-3000 (EYELA, Tokyo Rikakikai). In addition, a 7890A gas chromatograph (Agilent, USA), equipped with DB-FFAP quartz capillary chromatography column (60 m × 0.25 mm × 0.25 μm) (Agilent, USA). The TQ456 gas chromatograph was coupled with a mass spectrometer (GC-MS) (Bruker, USA) and a BR-5 elastic quartz capillary column (30 m × 0.25 mm × 0.25 μm). The Avance III 400 MHz nuclear magnetic resonance spectrometer (Bruker, Ferrandon, Switzerland).

Curcumin (purity > 98%) was purchased from Push Bio-Technology Co., Ltd. (Chengdu, China). The drug 5-FU (purity > 98%) was purchased from Macklin Biochemical Co., Ltd. (Shanghai, China). Soybean lecithin, cholesterol, and DSPE–MPEG 2000 were purchased from A. V. T. (Shanghai, China) Pharmaceutical Co., Ltd. Methanol and acetonitrile of high-performance liquid chromatography (HPLC) grade were purchased from Thermo Fisher Scientific (Shanghai, China). HPLC-grade phosphoric acid and acetic acid were purchased from Chengdu Kelong Chemical Co., Ltd. (Chengdu, China). HQ fetal bovine serum (FBS) was purchased from TransGen Biotech Co., Ltd. (Beijing, China). DMEM and McCoy’s 5A culture medium were purchased from HyClone™ (Beijing, China). Cell Counting Kit-8 (CCK-8) was purchased from Labgic Technology Co., Ltd. (Beijing, China). Phosphate-buffered saline (PBS; pH 7.4) was prepared in the laboratory, and ultrapure water was produced using a ULUPURE integral water purification system (Chengdu, China). All other chemicals were of analytical grade.

Analytical-grade oxalic acid, potassium acetate, 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), and FRAP working solution were obtained from Sangon Biotech Co., Ltd. (Shanghai, China). Analytical-grade ethanol, acetone, petroleum, acetic acid, aluminum trichloride, and ferrous sulfate (FeSO₄·7H₂O) were purchased from Chengdu Kelong Chemical Co., Ltd. (Chengdu, China). The standards of chlorophylls (a and b), carotenoids (neo-xanthin, violaxanthin, lutein, and β-carotene), authentic ascorbic acid, and quercetin were obtained from Solarbio Science & Technology Co., Ltd. (Beijing, China). HPLC-grade isopropanol, acetonitrile, and methyl alcohol were purchased from Tedia Company, Inc. (Fairfield, OH, USA). The spectrophotometer was purchased from Shanghai Mapada Instruments Co., Ltd. in China. High-performance liquid chromatography (HPLC) analysis of ascorbic acid and individual phenolic compounds was carried out using a Shimadzu LC-10AT system equipped with a UV detector (Shimadzu Scientific Instruments Inc., Kyoto, Japan). The mass spectrometer (Agilent 1100 SL, Santa Clara, CA, USA) was equipped with dual electrospray ionization (ESI) source. The freeze-dryer FDU-2110 was purchased from Tokyo Physicochemical Equipment Co., Ltd. (EYELA) in Tokyo, Japan.