Black mulberry (Morus nigra L.) fruits: As a medicinal plant rich in human health-promoting compounds

Morus nigra, black mulberry, is the most attractive among mulberry species. The study aimed to determine human health-promoting content and antifungal activity in fruits of seven black mulberry genotypes grown in the Tortum district of Turkey. The genotypes exhibited significant differences in most of the human health-promoting content. Among individual sugars and organic acids, glucose (6.98-8.03 g/100 g fresh weight base) and malic acid (6.33-10.45 g/100 g fresh weight base) were predominant. The ascorbic acid content of genotypes was found between 18.13 and 26.77 mg/100 g fresh weight base, indicating that black mulberry fruits had moderate ascorbic acid content. Total phenolic content, total antioxidant capacity, and total anthocyanin contents in fruit extracts of seven black mulberry genotypes were also investigated. The results showed that the levels of the aforementioned parameters changed depending on genotypes. The total phenolic and total anthocyanin contents were in the range of 1,656-2,348 μg gallic acid equivalent (GAE)/g and 623-804 μg C3GE (cyanidin-3-glucoside equivalent)/g, respectively. The genotypes had antioxidant capacity between 17.41 and 3.86 μg/mL and between 10.08 and 14.11 μmol TE/g measured by the 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assay, respectively. Some of the genotypes (TOR-1 and TOR-2) had high antifungal activity particularly against C. albicans. It was determined that the people living in the region traditionally use mulberries as blood enhancer, immune system booster, and mouth lesion treatments to protect themselves against different types of cancers and against inflammation. The present results confirm that attractive fruits of black mulberry are a rich natural source of phenolic antioxidants and can contribute to the dietary intake of antioxidants, depending on genotypes.