The polysaccharides derived from various deproteinization methods were prepared from Flos Sophorae Immaturus (FSI) to investigate the prebiotic efficacy of Lactobacillus fermentum (L. f ). The implications of polysaccharides from FSI (PFSI) gained after purification performed by non-deproteinization and different deproteinization processes (Savage method. papain method. https://www.thebrickes.shop/product-category/dog-treats/