Edible neotropical blueberries: antioxidant and compositional fingerprint analysis

Area of Science:

• Phytochemistry
• Nutraceuticals
• Plant Science

Background:

• Edible berries, particularly blueberries (Ericaceae family), are known for health benefits.
• Investigation of lesser-known New World tropical blueberry relatives alongside Vaccinium corymbosum is crucial for understanding diverse phytochemical profiles.
• Antioxidant properties and phenolic composition are key indicators of potential health impacts.

Purpose of the Study:

• To compare the antioxidant activities and phenolic profiles of North American highbush blueberry with five neotropical blueberry relatives.
• To identify specific phenolic compounds responsible for antioxidant properties in these berries.
• To determine if antioxidant profiles are distinct among the studied blueberry species.

Main Methods:

• Assessed antioxidant properties using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) free radical scavenging assays, and iron chelation assays.
• Quantified total phenolic content.
• Utilized high-performance liquid chromatography with photodiode array detection (HPLC-PDA) for compositional fingerprinting and phenolic constituent identification.
• Employed Principal Component Analysis (PCA) to analyze antioxidant and phenolic data.

Main Results:

• Neotropical berries Cavendishia grandifolia and Anthopterus wardii demonstrated significantly higher DPPH and ABTS radical scavenging activities and iron chelation capacity than Vaccinium corymbosum.
• Significant correlations were found between total phenolic content and antioxidant activities (DPPH, ABTS, iron chelation).
• HPLC-PDA analysis identified phenolic compounds including chlorogenic acid, p-coumaric acid, hyperoside, quercetin-3-O-glucoside, isoorientin, isovitexin, orientin, and vitexin.
• PCA revealed distinct clustering for each fruit species, indicating unique antioxidant profiles and accounting for 95% of the total variation.

Conclusions:

• Certain neotropical blueberries possess superior antioxidant potential compared to the common highbush blueberry.
• The phenolic composition is strongly correlated with the observed antioxidant activities.
• Each blueberry species exhibits a unique phytochemical fingerprint, suggesting diverse nutraceutical applications.