Farinha Inês, Baptista Sílvia, Reis Maria A M, Freitas Filomena
Pharma 73, S.A., Edifício Arcis, Rua Ivone Silva, 6, 4º Piso, 1050-124 Lisboa, Portugal.
UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal.
Life (Basel). 2022 Jan 21;12(2):161. doi: 10.3390/life12020161.
The yeast was cultivated under different dissolved oxygen (DO) levels (5, 15, 30 and 50% of the air saturation) to evaluate its impact on the production of the cell-wall polysaccharide chitin-glucan complex (CGC) and mannans. Decreasing the DO level from 50 to 15% had no significant impact on cell growth but substrate conversion into biomass was improved. Under such conditions, a mannans content in the biomass of 22 wt% was reached, while the CGC content in the biomass was improved from 15 to 18 wt%, confirming that the DO level also impacted on cell-wall composition. Overall mannans and CGC volumetric productivity values of 10.69 and 8.67 g/(L. day) were reached, respectively. On the other hand, the polymers' composition was not significantly affected by decreasing the DO level. These results demonstrated that considerable energy savings can be made in the polysaccharide production process by reducing the DO level during cultivation of by improving the overall polymers' productivity without altering their composition. This has impact on the polysaccharide production costs, which is of considerable relevance for process scale-up and products' commercialization.
将酵母在不同溶解氧（DO）水平（空气饱和度的5%、15%、30%和50%）下培养，以评估其对细胞壁多糖几丁质-葡聚糖复合物（CGC）和甘露聚糖产量的影响。将溶解氧水平从50%降至15%对细胞生长没有显著影响，但底物向生物质的转化得到了改善。在这种条件下，生物质中的甘露聚糖含量达到22 wt%，而生物质中的CGC含量从15 wt%提高到18 wt%，证实溶解氧水平也影响细胞壁组成。甘露聚糖和CGC的总体积生产率分别达到10.69和8.67 g/(L·天)。另一方面，降低溶解氧水平对聚合物组成没有显著影响。这些结果表明，在多糖生产过程中，通过在培养过程中降低溶解氧水平，可以在不改变聚合物组成的情况下提高总体聚合物生产率，从而实现可观的节能。这对多糖生产成本有影响，这对于工艺放大和产品商业化具有相当重要的意义。
