Fumaric acid

All the standards for high performance liquid chromatography (HPLC), including l-rhamnose monohydrate, fructose, glucose, sucrose, maltose, d-trehalose anhydrous, oxalic acid, tartaric acid, malic acid, α-ketoglutaric acid, lactic acid, citric acid, fumaric acid, succinic acid, ascorbic acid (HPLC grade) were obtained from Shanghai YuanYe Biotechnology (Shanghai, China). Other chemicals were obtained from Tianjin Guangfu Chemical Reagent (Tianjin, China). All reagents were either analytical grade or HPLC grade.

Analytical purity: sulfuric acid, sodium chloride, potassium chloride, sodium bicarbonate (Beijing Chemical Factory, Beijing, China); tannic acid (Tianjin Guangfu Fine Chemical Research Institute, Tianjin, China); Folin-Denis reagent (US sigma, St. Louis, MO, USA); anhydrous sodium carbonate (Tianjin Hengxing Chemical Reagent Manufacturing Co., Ltd., Tianjin, China); glacial acetic acid, hydrochloric acid, anhydrous ethanol, sodium hydroxide, phosphoric acid (Beijing Chemical Factory); potassium hydrogen phthalate, anthrone (Sinopharm Chemical Reagent Co., Ltd., Shanghai, China); anhydrous sodium acetate (Shanghai Hutian Chemical Co., Ltd., Shanghai, China); glucose (Guangzhou Jinhuada Chemical Reagent Co., Ltd., Guangzhou, China).
Chromatographic purity: methanol (TEDIA Reagents, Fairfield, OH, USA); succinic acid, fumaric acid, malic acid, citric acid anhydrous (Shanghai Yuanye Biotechnology Co., Ltd., Shanghai, China); 4-methyl-2-pentanol (Shanghai Lianshuo Biotechnology Co., Ltd., Shanghai, China); glacial acetic acid, tartaric acid, lactic acid (Tianjin Fine Chemical Research Institute, Tianjin, China)
Fermentation auxiliaries: CEC01 active dry yeast (Angel Yeast Co., Ltd., Hubei, China); potassium metabisulphite (Yantai Dibs Homebrewer Co., Ltd., Yantai, China).