Abstract：
This study explores the enhancement of phosphate rock (PR) solubilization through solid-state fermentation (SSF) by optimizing oxalic acid production using Aspergillus niger. Key process parameters, including the use of agro-industrial by-products (sugarcane bagasse (SCB), wheat bran (WB), soybean bran (SB)), pH levels, sucrose supplementation, and methanol addition, were systematically evaluated through sequential experimental designs. The results identified SCB and SB in a 1:1 ratio as the most effective substrate. Remarkably, the inclusion of methanol (7 %) and sucrose (0.5 %) resulted in a 3-fold increase in oxalic acid production. Under these optimized conditions, significant phosphorus solubilization of Bayóvar, Itafós, and Registro PRs was achieved, with Bayóvar rock releasing up to 12.1 g/kgds of soluble P (63.8 % efficiency). Additionally, the SSF process effectively released organic phosphorus from the agro-industrial substrates. These findings hold promise for advancing the bio-based economy and developing future industrial biofertilizers.
摘要：
这项研究探索了通过使用黑曲霉优化草酸生产，通过固态发酵（SSF）来增强磷矿（PR）溶解。关键工艺参数,包括使用农业工业副产品(甘蔗渣(SCB)，麦麸(WB),大豆麸皮（SB）），pH值,蔗糖补充，和甲醇添加，通过序贯实验设计进行了系统评估。结果确定比例为1:1的SCB和SB是最有效的底物。值得注意的是,包含甲醇（7％）和蔗糖（0.5％）导致草酸产量增加3倍。在这些优化条件下，显著的磷溶解的Bayóvar，Itafos,并且实现了注册PR，Bayóvar岩石释放高达12.1g/kgds的可溶性磷（效率为63.8％）。此外,SSF工艺有效地从农用工业基质中释放有机磷。这些发现为推进生物经济和开发未来的工业生物肥料提供了希望。
