Vassileva María, Martos Vanessa, Del Moral Luis F García, Vassilev Nikolay
Instituto de Biotecnología, Universidad de Granada, 18071 Granada, Spain.
Microorganisms. 2023 Apr 19;11(4):1064. doi: 10.3390/microorganisms11041064.
The ability of a strain to support acid production and simultaneously solubilize inorganic sources of phosphate in conditions of submerged, solid-state fermentation (SSF) and immobilized cell system was examined in this study. Abiotic stress factors such as NaCl and different values of pH were introduced into the different fermentation process schemes to measure the fungal response. The results showed a higher tolerance of when the fermentation process was carried out in solid-state and immobilized-cell conditions, which mimics the natural state of the soil microorganisms. The acidic culture conditions were not found to be suitable for fungal growth, which increased at a higher pH, with values of 4.0 and 6.0 being optimal for all types of fermentation. The presence of increasing amounts of NaCl provoked low biomass growth, titratable acidity, and simultaneous phosphate (P) solubilization. These results were, however, less pronounced at pH 4.0 and 6.0, particularly in conditions of SSF. Studying stress-tolerant microbial characteristics, particularly in different conditions and combinations of stress factors, is of great importance for further managing the overall microbial inoculants' production and formulation process as well as their applications in specific soil-plant systems.
本研究考察了一种菌株在深层发酵、固态发酵（SSF）和固定化细胞系统条件下支持产酸并同时溶解无机磷源的能力。将非生物胁迫因素如NaCl和不同pH值引入不同的发酵工艺方案中，以测定真菌的反应。结果表明，当在固态和固定化细胞条件下进行发酵过程时，该菌株具有更高的耐受性，这模拟了土壤微生物的自然状态。未发现酸性培养条件适合真菌生长，真菌在较高pH值下生长增加，4.0和6.0的值对所有类型的发酵都是最佳的。NaCl含量增加会导致生物量低增长、可滴定酸度以及同时的磷酸盐（P）溶解。然而，这些结果在pH 4.0和6.0时不太明显，特别是在固态发酵条件下。研究耐胁迫微生物特性，特别是在不同条件和胁迫因素组合下的特性，对于进一步管理微生物接种剂的整体生产和配方过程以及它们在特定土壤-植物系统中的应用非常重要。
