The Effect of Ripening Stages on the Accumulation of Polyphenols and Antioxidant Activity of the Fruit Extracts of Solanum Species

The aim of the research was to evaluate the influence of the ripening stage on the accumulation of polyphenols and antioxidant activity in fruits of Solanum species. The experiment included two factors: I-four different Solanum species (S. melanocerasum, S. nigrum, S. villosum, and S. retroflexum) and II-three ripening stages. High-performance liquid chromatography (HPLC) was used to analyze the individual phenolic compounds (flavonoids and phenolic acids), and the spectrophotometric method was applied to determine antioxidant activity. The results revealed that the accumulation of polyphenols and antioxidant activity in fruits of Solanum species depends on the stage of ripening and species. All studied Solanum species fruits had the highest content of total phenolic acid at ripening stage III and the greatest antioxidant activity at ripening stage I. Fully ripe fruits of S. melanocerasum contained significantly more total flavonoids, whereas S. nigrum contained significantly more total phenolic acids than other investigated Solanum species fruits. The significantly highest antioxidant activity was found in S. melanocerasum fruits at ripening stage I.

Automated summary

The research aimed to examine the impact of ripening stage on polyphenol accumulation and antioxidant activity in Solanum fruits. Four different Solanum species and three ripening stages were included in the experiment. High-performance liquid chromatography (HPLC) and spectrophotometric method were used to analyze phenolic compounds and determine antioxidant activity, respectively. The results showed that polyphenol accumulation and antioxidant activity in Solanum fruits depended on ripening stage and species. The highest total phenolic acid content was found in all Solanum fruits at ripening stage III, while the greatest antioxidant activity was observed at ripening stage I. S. melanocerasum fruits had significantly higher total flavonoid content, while S. nigrum fruits had significantly higher total phenolic acid content compared to the other species. The highest antioxidant activity was found in S. melanocerasum fruits at ripening stage I.