Phytochemical evaluation of white (Morus alba L.) and black (Morus nigra L.) mulberry fruits, a starting point for the assessment of their beneficial properties

• Mulberry fruits are being revalorized attending to their nutritional properties.
• Eight different clones from Morus alba and Morus nigra species were studied.
• The most complete evaluation of the phenolic content of mulberries to date.
• A huge intra-species variability in the phytochemical profile was noted.
• These data are critical for the development of rich-in-bioactives mulberry products.

This study evaluated, for the first time, the phenolic content of white (Morus alba) and black mulberry (Morus nigra) fruits with proven market aptitudes and grown in Spain, one of the main European producers. The antioxidant activity and mineral composition of these promising berry fruits were also assessed. Black mulberry clones showed higher antioxidant activity and amounts of phenolic compounds than white mulberry clones, although a wide intra-species variability was noted, according to principal component analysis. The total anthocyanins varied significantly among clones of M. nigra. These results are keys for the design of future dietary intervention studies examining the role of mulberry fruits in disease risk reduction. They can also be used for the development of mulberry derived-products rich in phenolic compounds.