Neutral red n7005

Bergenin (purity of 95%) was obtained from Meilun Biological Products Co. Ltd. (Dalian, China). The chemical structure of bergenin is shown in Figure 6. The cell culture products were from Gibco BRL (Grand Island, NY, USA). Injectable cyclophosphamide was obtained from Jiangsu Hengrui Medicine Co. (Lianyungang, Jiangsu, China). A HE staining kit was purchased from Beyotime (Jiangsu, China). Concanavalin A (Con A), lipopolysaccharide (LPS) and neutral red (N7005) were provided by Sigma-Aldrich (St. Louis, MO, USA). The Ig kit and cytokines ELISA kits were purchased from Lianke Biotechnology Co. Ltd. (Hangzhou, China). SOD, CAT, GSH-Px and MDA detection kits were provided by Nanjing Jiancheng Bio-engineering Institute (Nanjing, China). 2-(2-Methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, mono- sodium salt] (WST-8) was purchased from Amresco Co. (Solon, OH, USA) Anti-CD4⁺ (APC) and anti-CD8⁺ (PE) antibodies were provided by Bio Legend, Inc. (San Diego, CA, USA).

Methanol (MeOH), diethyl ether, tetrahydrofuran (THF), methyl tert-butyl ether (MTBE), and acetone were purchased from VWR International (Radnor, Pensilvania, USA); ultrapure water was obtained from a Millipak^® Express 40 system (Merk-Millipore, Darmstadt, Germany); anhydrous sodium sulfate, potassium hydroxide (KOH), and sodium chloride (NaCl) were purchased from Panreac Quimica (Barcelona, Spain); butylated hydroxytoluene (BHT) and magnesium carbonate were obtained from Acros Organics (New Jersey, USA). Standards for lycopene (L9879, ≥90%, from tomato), lutein (X6250 from marigold), and (all-E)-β-apo-8’-carotenal (10810, ≥96%, (ultraviolet (UV))) were purchased from Sigma-Aldrich (St. Louis, Missouri, USA). Standards for (all-E)-β-carotene (HPLC 96%, synth., cryst.), (all-E)-α-carotene (HPLC 97%, synth., cryst.), (all-E)-β-cryptoxanthin (HPLC 97%, synth., cryst.), (all-E)-zeaxanthin (HPLC 97%, synth., cryst.), (all-E)-neoxanthin (HPLC 97%, isolated, cryst.), and (all-E)-violaxanthin (HPLC 95%, isolated, cryst.) were from CaroteNature (Ostermundigen, Switzerland). Reagents used for microscopy (neutral red (N7005, ≥90% and calcofluor white stain) were obtained from Sigma-Aldrich (St Louis, MO, USA).