"Plant Golden" C. sativus: Qualitative and quantitative analysis of major components in stigmas and petals and their biological activity in vitro.

ABSTRACT

Crocus sativus L. (C. sativus) has its stigma as the main valuable part used. With extremely low production and high prices, stigma is considered a scarce resource. As a result, its petals, considered as by-products, are often discarded, leading to significant waste. We developed a UPLC-Q-Orbitrap HRMS method for qualitative analysis of stigmas and petals and a UHPLC-QQQ-MS/MS method for simultaneous quantification of 9 characteristic active compounds for the first time, and compared their biological activity in vitro. The results indicated that a total of 63 compounds were identified in the petals and stigmas. The content of flavonoids in the petals was significantly superior to that in the stigma, and the content of quercetin in the petals was 50 times higher than that in the stigma. The results of the in vitro evaluation of biological activity indicated that both the petals （•OH IC50=39.70 mg/mL; DPPH IC50=28.37 mg/mL; ABTS IC50=0.9868 mg/mL）and stigma （•OH IC50=34.41 mg/mL; DPPH IC50=38.99 mg/mL; ABTS IC50=3.194 mg/mL）demonstrated comparable antioxidant activities. However, the tyrosinase inhibitory activity in petals （IC50=21.17 mg/mL） was weaker than that in stigma（IC50=1.488 mg/mL）. This study provides a fast, reliable, and efficient analytical method that can be used for the quality assessment of petals as a natural resource and its related products in the food and pharmaceutical industries.