Purification, sequence identification, and taste-presenting mechanism analysis of four novel taste-active peptides...

Shiitake mushroom-derived taste-active peptides were prepared by enzymatic hydrolysis and purified step-by-step using D001 macroporous adsorption resin, Sephadex G-100 gel filtration, and reversed-phase high-performance liquid chromatography. The initial hydrolysate contained 16.12 mg/mL peptides with saltiness and umami scores of 6. The active fraction was screened by electronic tongue and sensory evaluation, and four novel peptides (PDDER, QPEEQDER, SPDDER, and WEPGPQ) were identified by liquid chromatography tandem mass spectrometry-based de novo sequencing, all exhibiting strong binding to the heterodimeric umami receptor T1R1/T1R3 via hydrogen bonds and electrostatic interactions. Verification with synthesized peptides confirmed their favorable taste-active properties, excellent aqueous solubility, non-toxicity and non-allergenicity, demonstrating their potential for further development as umami-enhancing ingredients. Among them, SPDDER performed best, with outstanding electronic tongue response values (umami 9.68, salty 8.54) and sensory scores (umami 9.5, salty 8.5). Thereby providing a methodological and theoretical basis for producing taste-active peptides from macro-fungi.