Investigation of Antioxidant Content and Capacity in Yellow European Plums

Abstract

Phenolic content and antioxidant capacity of five Yellow European plums (Prunus domestica) were studied using heat reflux extraction. Fresh plums were extracted at 50°C and 70°C, while freeze dried plums were extracted at 50°C, 60°C, and 70°C. Quantification of phenolic compounds such as ascorbic acid, neochlorogenic acid, and chlorogenic acid, was performed using high performance liquid chromatography. Antioxidant activity was determined by evaluating the scavenging ability of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric (Fe 3+ ) free radicals. Total phenolic content and ferric reducing antioxidant potential were highest for freeze dried samples extracted at 60°C whereas extraction at 70°C resulted in the lowest yield. Neochlorogenic acid was the predominant phenolic compound in each plum genotype followed by ascorbic acid and chlorogenic acid. This study demonstrates that there is an adequate amount of health promoting phytochemicals within European plums, hence extraction of these compounds have potential for use towards functional food, nutraceutical, and pharmaceutical industries.

Optimization of microwave‐assisted extraction parameters and characterization of phenolic compounds in Yellow European Plums

“…All genotypes were found to contain a high concentration of neochlorogenic acid, followed by chlorogenic acid, and ascorbic acid. This is consistent with other studies that have reported neochlorogenic acid to be the predominant compound found in plums and other stone fruits …”

“…Also, V97261, in comparison to other genotypes studied, yielded the lowest scavenging activity. This observation was also reported by DiNardo et al, who stated that V97261 yielded the lowest scavenging activity among all other genotypes due to its large size.…”

“…The first experiment optimized extraction parameters for MAE, which included solid‐to‐solvent ratio (0.05, 0.1, and 0.15 g/mL) and solvent concentration (20, 60, and 100 %), using ethanol and methanol, for one genotype of YEP, V94021. This genotype was chosen as it has been observed to exhibit large phenolic content and antioxidant capacity for freeze dried plums . The desired amount of freeze dried plum was placed into a 75 mL quartz reaction vessel with 25 mL of varying concentration solvents to satisfy the solid‐to‐solvent ratios in Table .…”

“…High performance liquid chromatography (HPLC) was used to quantify ascorbic acid, neochlorogenic acid, and chlorogenic acid in the extracts, as these are the compounds predominantly found in plums . A Beckman Coulter System Gold instrument was used and consisted of a 166 UV detector, set at 280 nm, a 126 solvent pump, and a 508 refrigerated autosampler, set at 12 °C.…”

“…European plums are traditionally blue‐violet in colour; however, through conventional breeding programs, Yellow European Plums (YEPs) have been developed. Despite lacking the traditional dark coloured skin and flesh, YEPs have demonstrated to exhibit higher phenolic and antioxidant activity in comparison to traditional European and Japanese plums . YEPs are predominantly high in polyphenols such as ascorbic acid, chlorogenic acid, caffeoylquinic acid, cyanidin‐3‐glucoside, and neochlorogenic acid .…”