Comparative analysis of the antioxidant compounds of raw edible flowers and ethanolic extracts of Cucurbita pepo, Tagetes erecta, and Erythrina americana during storage

This work determined the antioxidant compounds of the raw flowers of the zucchini plant, Mexican marigold, and colorin and their ethanolic extracts, which were stored by 270 days for their potential use as functional food. The DPPH^• radical scavenging capacity was in a range of 50%–95% for the three raw flower species, but the ethanolic extracts of flowers (EEF) of the zucchini plant and colorin lost up to 80% of these compounds. The total phenols of raw flowers and EEF were of 0.3–2.5 mg gallic acid equivalents (GAE)/g. The total flavonoids were up to 85% higher in the EEF of the nondehydrated Mexican marigold than in the raw flowers. In the remaining treatments, there had no notables changes (~0.5 mg quercetin/g). Rutin, quercetin, myricetin, and lucenin were in the EEF of the nondehydrated samples. In conclusion, EEF of nondehydrated Mexican marigold showed higher antioxidant composition than remaining extracts. Practical applications: This study demonstrates the presence of antioxidant compounds in three edible flowers produced worldwide for ornamental and industrial purposes, except in Mexico, where they are endemic plants and are also consumed as food. Antioxidant compounds of the evaluated edible flowers can be found in nondehydrated samples and dehydrated, and they can be extracted and preserved for 270 days using cane alcohol as the solvent.