Assessment of phenolic, flavonoid, total antioxidant, and anthocyanin contents of various colored hawthorn fruits for their potential as functional foods

Abstract

One of the wild fruit species that stands out for its diverse applications is hawthorn (Crataegus spp.). Hawthorn is valued as a medicinal plant due to its bioactive substances, such as flavonoids, phenolic compounds, and antioxidants. Additionally, it has become increasingly popular for fresh consumption in recent years. The aim of the study was to determine the functional food potential of fresh hawthorn fruits with assessing their phenolic, flavonoid, anthocyanin, and antioxidant capacities. The study material consisted of fresh hawthorn (Crataegus spp.) fruits that reached optimum maturity and naturally grew in the autumn season in Çorum province, Turkey. The fruits were randomly collected from 10 different sources at the same maturity period and divided into two different colors (yellow–Group 1 and orange–Group 2). Phenol compounds, total flavonoid, total antioxidant levels, anthocyanin, and ascorbic acid amounts of hawthorn fruits were determined by the Folin–Ciocalteu method, aluminum chloride method, Rel Assay brand commercial kits, pH differential method, and the spectrophotometric method, respectively. Fresh hawthorn fruits of two different colors at optimum maturity were analyzed. Orange hawthorn (Group 2) exhibited higher phenol and total flavonoid levels compared to yellow hawthorn (Group 1). However, tannin content of Group 2 was lower, but this difference was not statistically significant (P > 0.05). Ascorbic acid concentration was significantly lower in orange hawthorn (Group 2) compared to yellow hawthorn (Group 1) (P < 0.05). Anthocyanin levels were higher in orange hawthorn (Group 2) compared to yellow hawthorn (Group 1) (P > 0.05). Similarly, total antioxidant capacity was higher in orange hawthorn (Group 2) than in yellow hawthorn (Group 1) (P > 0.05). Correlation analysis revealed a significant positive correlation between phenolic content and total antioxidant status (TAS) (r = 0.828**) and between flavonoids and TAS (r = 0.750**). Additionally, there was a significant positive correlation between flavonoids and TAS (r = 0.818**). A significant negative correlation was found between ascorbic acid and anthocyanins (r = − 0.467*). The results indicate that fresh hawthorn fruits of different colors, at the same ripeness stage, contain compounds that can provide significant health benefits. Due to their high levels of total phenolics, flavonoids, anthocyanins, total antioxidants, and ascorbic acid, these fruits could be utilized in the development of functional foods.