State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Bioresour Technol. 2011 Apr;102(7):4807-14. doi: 10.1016/j.biortech.2010.10.124. Epub 2010 Oct 31.
The immediate precursor of L-ascorbic acid, or vitamin C, is 2-keto-L-gulonic acid (2-KLG). This is commonly produced commercially by Ketogulonicigenium vulgare and Bacillus megaterium, using corn steep liquor powder (CSLP) as an organic nitrogen source. In this study, the effects of the individual CSLP components (amino acids, vitamins, and metal elements) on 2-KLG production were evaluated, with the aim of developing a complete, chemically defined medium for 2-KLG production. Forty components of CSLP were analyzed, and key components were correlated to biomass, 2-KLG productivity, and consumption rate of L-sorbose. Glycine had the greatest effect, followed by serine, biotin, proline, nicotinic acid, and threonine. The combination of 0.28 g L(-1) serine, 0.36 g L(-1) glycine, 0.18 g L(-1) threonine, 0.28 g L(-1) proline, 0.19 g L(-1) nicotinic acid, and 0.62 mg L(-1)biotin in a chemically defined medium produced the highest maximum biomass concentration (4.2 × 10(9) cfu mL(-1)), 2-KLG concentration (58 g L(-1)), and yield (0.76 g g(-1)) after culturing for 28 h.
L-抗坏血酸(维生素 C)的直接前体是 2-酮基-L-古洛糖酸(2-KLG)。通常,酮古龙酸菌(Ketogulonicigenium vulgare)和巨大芽孢杆菌(Bacillus megaterium)利用玉米浆干粉(CSLP)作为有机氮源来生产 2-KLG。在这项研究中,评估了 CSLP 各成分(氨基酸、维生素和金属元素)对 2-KLG 生产的影响,目的是开发一种用于 2-KLG 生产的完全、化学定义的培养基。分析了 CSLP 的 40 种成分,并将关键成分与生物量、2-KLG 生产力以及 L-山梨糖的消耗速率相关联。甘氨酸的效果最好,其次是丝氨酸、生物素、脯氨酸、烟酸和苏氨酸。在化学定义的培养基中组合使用 0.28 g L(-1)丝氨酸、0.36 g L(-1)甘氨酸、0.18 g L(-1)苏氨酸、0.28 g L(-1)脯氨酸、0.19 g L(-1)烟酸和 0.62 mg L(-1)生物素,可在 28 h 的培养后获得最高的最大生物量浓度(4.2×10(9) cfu mL(-1))、2-KLG 浓度(58 g L(-1))和产率(0.76 g g(-1))。