L-Malic acid (L-MA) is widely used in food and non-food products. However, few microorganisms have been able to efficiently produce L-MA from xylose derived from lignocellulosic biomass (LB). The objective of this work is to convert LB into L-MA with the concept of a bioeconomy and environmentally friendly process. The unique trifunctional xylanolytic enzyme, PcAxy43A from Paenibacillus curdlanolyticus B-6, effectively hydrolyzed xylan in untreated LB, especially corn hull to xylose, in one step. Furthermore, the newly isolated, Acetobacter tropicalis strain H1 was able to convert high concentrations of xylose derived from corn hull into L-MA as the main product, which can be easily purified. The strain H1 successfully produced a high L-MA titer of 77.09 g/l, with a yield of 0.77 g/g and a productivity of 0.64 g/l/h from the xylose derived from corn hull. The process presented in this research is an efficient, low-cost and environmentally friendly biological process for the green production of L-MA from LB.

中文翻译：

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通过来自 Paenibacillus curdlanolyticus B-6 和 Acetobacter tropicalis H-1 的三功能木聚糖分解酶将未处理的玉米壳生物转化为 L-苹果酸。

L-苹果酸 (L-MA) 广泛用于食品和非食品中。然而，很少有微生物能够从源自木质纤维素生物质 (LB) 的木糖中有效地生产 L-MA。这项工作的目的是利用生物经济和环境友好的过程将 LB 转化为 L-MA。来自Paenibacillus curdlanolyticus B-6的独特的三功能木聚糖酶 PcAxy43A可一步有效地将未处理的 LB 中的木聚糖，尤其是玉米壳水解为木糖。此外，新分离的热带醋杆菌菌株H1能够将玉米壳中的高浓度木糖转化为L-MA作为主要产物，易于纯化。菌株 H1 成功地从源自玉米壳的木糖中产生了 77.09 g/l 的高 L-MA 效价，产量为 0.77 g/g，生产率为 0.64 g/l/h。本研究提出的工艺是一种高效、低成本、环保的生物工艺，用于从 LB 绿色生产 L-MA。