Microbial screening and process optimization for efficient removal of ginkgolic acids from Ginkgo biloba leaf

Abstract

This study aimed to screen microorganisms capable of removing ginkgolic acids (GAs) from Ginkgo biloba leaf. Given the presence of long alkyl side chains in GAs, the study first focused on screening microorganisms that could utilize long-chain alkanes (n-tridecane, n-pentadecane, and n-heptadecane) and further studying their GAs degradation abilities. The results showed that the degradation rates of GAs by the two bacteria strains (identified as Pantoea sp.) were about 50 %, and the degradation rates of GAs by the nine fungal strains (identified as Fusarium sp.) were about 95 %. Meanwhile, Lactiplantibacillus plantarum was also found to exhibit a robust capacity for degrading GAs. Through further optimization of the medium components and fermentation conditions, Lactiplantibacillus plantarum achieved a degradation rate of 81.581 % for total GAs after 72 hours of cultivation. Notably, this process did not significantly impact flavonoids and terpene lactones present in Ginkgo biloba extract (EGb), which are essential for its therapeutic properties. Additionally, the results demonstrated that the hydrophobicity of GAs significantly influenced the degradation efficiency of GAs by Lactiplantibacillus plantarum. This study highlights the potential industrial application value of Lactiplantibacillus plantarum in the production of ginkgo products with low GAs content, thereby enhancing the safety and efficacy of this widely used medicinal plant.