Efficient Extraction of Alkaloids From Sophora moorcroftiana Seeds via Enzyme and Ultrasound‐Assisted Coupling and Their Antibacterial Activity

Sophora moorcroftiana, widely distributed in Xizang and rich in alkaloids, warrants further exploration and utilization. This study aims to analyze the efficiency of enzyme-assisted ultrasonic extraction with the standard solvent method comparatively for the qualitative and quantitative analysis of alkaloids in S. moorcroftiana seeds. The research identified optimal extraction conditions, which included an enzyme (cellulose-hemicellulose complex enzyme) concentration of 10% (w/w), an ultrasonic duration of 45 min, an ultrasonic power of 267.01 W, a solid-liquid ratio of 1:44.82 (v/v), and an ethanol concentration of 77.18%. Under these conditions, the extraction efficiency reached 90.65%, and successfully isolated sophocarpine with a purity of 91.41%. The seeds contained 6.85% moisture and 4.00% alkaloids, with oxymatrine accounting for 2.45%, oxysophocarpine 0.35%, matrine 0.73%, and sophocarpine 0.47%. In addition, the employment of enzymatic hydrolysis-assisted ultrasonic coupling extraction methodology resulted in a 32.5% increase in extraction efficiency compared to the conventional solvent extraction approach. Total alkaloids and the compound sophocarpine demonstrate significant inhibitory effects on both Escherichia coli and Staphylococcus aureus. This study demonstrates that ultrasound-assisted enzyme-coupled extraction is a sustainable and efficient technique with potential applications in the extraction of natural products.