Complex sentence: Most polyphenol studies have been conducted using the highbush cultivar of blueberries ("V. corymbosum "), while content of polyphenols and anthocyanins in lowbush (wild) blueberries ("V. angustifolium") exceeds values found in highbush cultivars.
Split into simpler sentences: Most polyphenol studies have been conducted using the highbush cultivar of blueberries ("V. corymbosum "). The content of polyphenols and anthocyanins in lowbush (wild) blueberries ("V. angustifolium") exceeds their content in highbush cultivars.