Teune Michelle, Suster Christoph, Wolf Yannick, Michels Nils, Mieth Henrieke, Döhler Thorben, Bartosik Daniel, Krull Joris, Hehemann Jan-Hendrik, Schweder Thomas, Stanetty Christian, Bornscheuer Uwe T
Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, 17489, Greifswald, Germany.
Institute of Applied Synthetic Chemistry, TU Wien, 1060, Vienna, Austria.
Biotechnol Biofuels Bioprod. 2025 Aug 5;18(1):87. doi: 10.1186/s13068-025-02686-7.
The red alga Palmaria palmata is a rich source of sugar compounds, particularly mixed-linkage xylans present in the cell walls of the algae. In contrast to their terrestrial lignocellulosic counterparts, these xylans are more easily accessible. They can be hydrolyzed enzymatically into valuable xylooligosaccharides (XOS), known for their prebiotic, antioxidant, and immunomodulatory properties.
This study introduces a simplified, one-step enzymatic process utilizing the endo-1,4-β-xylanase FO15_GH10 that directly hydrolyzes P. palmata biomass to produce XOS, eliminating the need for prior xylan extraction and improving efficiency. The exact structure of the resulting XOS was determined using NMR and MS/MS techniques. In addition, the xylosidase FO17_GH43 can be added to break down all residual 1,4-linked XOS. As a result, only 1,3- and mixed-linkage XOS (degree of polymerization (DP) 2-4) remains under simultaneous increase of the xylose obtained. Using FO15_GH10 alone, it was possible to produce approximately 17.6 (± 0.16) % (176 mg) XOS from 1 g of powdered biomass while combining both enzymes resulted in 22.6 (± 0.51) % (226 mg) XOS. Further optimization upon upscaling offers the possibility of achieving even greater improvements.
In summary, our one-step enzymatic approach offers an efficient and sustainable method for producing XOS directly from P. palmata biomass. This streamlined process overcomes the need for resource-consuming extraction processes. The further characterization of the obtained XOS and the potential to gain solely 1,3- and mixed-linkage XOS is paving the way for future studies on their functional properties.
红藻掌状红皮藻是糖化合物的丰富来源，尤其是存在于藻类细胞壁中的混合连接木聚糖。与陆地木质纤维素对应物相比，这些木聚糖更容易获取。它们可以通过酶水解成有价值的木寡糖（XOS），木寡糖以其益生元、抗氧化和免疫调节特性而闻名。
本研究引入了一种简化的一步酶促过程，利用内切-1,4-β-木聚糖酶FO15_GH10直接水解掌状红皮藻生物质以生产XOS，无需事先提取木聚糖并提高了效率。使用核磁共振（NMR）和串联质谱（MS/MS）技术确定了所得XOS的确切结构。此外，可以添加木糖苷酶FO17_GH43来分解所有残留的1,4-连接的XOS。结果，仅保留了木糖含量同时增加的1,3-连接和混合连接的XOS（聚合度（DP）为2-4）。仅使用FO15_GH10，从1克粉末状生物质中可生产约17.6（±0.16）%（176毫克）的XOS，而两种酶结合使用则产生22.6（±0.51）%（226毫克）的XOS。扩大规模后的进一步优化提供了实现更大改进的可能性。
总之，我们的一步酶促方法提供了一种直接从掌状红皮藻生物质生产XOS的高效且可持续的方法。这种简化的过程克服了对资源消耗大的提取过程的需求。对所得XOS的进一步表征以及仅获得1,3-连接和混合连接XOS的潜力为其功能特性的未来研究铺平了道路。
