β nicotinamide adenine dinucleotide phosphate reduced tetrasodium salt nadph

Streptozotocin (STZ), 6-hydroxydopamine, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox) and 2-thiobarbituric acid (TBA), and β-nicotinamide adenine dinucleotide phosphate reduced tetrasodium salt (NADPH) were obtained from Sigma-Aldrich (Johannesburg, South Africa). Malondialdehyde bis (diethyl acetal) (MDA), hexane, and methanol were purchased from Merck (Johannesburg, South Africa). All other chemicals and reagents used were of the highest commercially available purity.

Berberine hydrochloride, coptisine hydrochloride, palmatine hydrochloride, and jatrorrhizine hydrochloride were purchased from the National Institute for the Control of Pharmaceutical and Biological Products (Beijing, China). β-Nicotinamide adenine dinucleotide phosphate reduced tetrasodium salt (NADPH) was purchased from Sigma-Aldrich Co. (St. Louis, MO, USA). HPLC-grade methanol and acetonitrile were obtained from Tedia Company Inc. (USA). Phosphate-buffered saline (PBS, 0.1 M) was supplied by Gibco Laboratories (MD, USA). Deionized water was purified using a Milli-Q system (Millipore Corporation, USA). Dimethyl sulfoxide (DMSO), ammonium acetate, and other chemicals were all of analytical grade and were supplied by Sinopharm Chemical Reagent Co. Ltd. (Beijing, China).

Streptozotocin (STZ), quercetin, 6-hydroxydopamine, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) and 2-thiobarbituric acid (TBA) and β-nicotinamide adenine dinucleotide phosphate reduced tetra-sodium salt (NADPH) were obtained from Sigma-Aldrich (Johannesburg, South Africa). Methanol, malondialdehyde bis (diethyl acetal) (MDA), n-hexane were purchased from Merck (Johannesburg, South Africa). Other chemicals were of the highest grade and procured from Sigma-Aldrich (St. Louis, MO, USA) and Merck (Darmstadt, Germany).