LC-MS/MRM analysis of bioactive compounds from saffron (Crocus sativus L.) by-products: Optimization of phenolic compounds recovery using simplex centroid mixture design

[Display omitted] •Extracting polyphenols and selecting the ideal solvents for maximum yield pose major challenges.•Simplex centroid mixture design was utilized to enhance the yields of phenolic compounds.•Experiments were conducted using combinations of water, ethanol, and methanol solvents.•Saffron by-products are being promoted for their bioactive compounds. There’s growing evidence suggesting that natural antioxidants, like those found in saffron (Crocus sativus L.), offer health benefits. However, extracting polyphenols, which are believed to be the antioxidants’ source, and choosing the right solvents for optimal yields, present significant challenges. This study aimed to enhance phenolic compounds extraction from saffron by-products (leaves and flowers) using simplex centroid mixture design. Different solvent combinations (water, ethanol, and methanol) were tested. The investigation revealed that a binary mixture of water and ethanol (3:1 v/v) emerged as the optimal solvent blend for achieving the highest phenolic compounds (110.19 mg GAE/g DM) for saffron flower. Conversely, a ternary mixture of water, ethanol, and methanol (1:1/3:1/6 v/v) proved most effective for optimizing total phenolic content response for saffron leaf (80.58 mg QE/g DM). Analysis via LC-MS/MS unveiled the presence of various flavonoids such as luteolin and quercetin, along with other phenolic compounds. The optimal extracts demonstrated potent antioxidant properties, with notable antibacterial activity against Staphylococcus aureus and Bacillus subtilis. Moreover, the extracts exhibited significant anti-diabetic activity. This research advocates for the utilization of saffron by-products as a valuable source of bioactive compounds suitable for various applications in the food, pharmaceutical, and cosmetic industries.