Phenotypic Variation and Peel Contribution to Fruit Antioxidant Contents in European and Japanese Plums

Abstract

Herein, we studied the variation in leaf and fruit morphological traits and antioxidant contents in 43 local and foreign cultivars (cvs) grown under the same experimental conditions in the widely cultivated plum species Prunus domestica and Prunus salicina. The peel contribution of fruit bioactive compounds in a serving portion, correlations among the examined parameters, and group patterns in each plum species were also studied. The species and cvs were sufficiently separated. Compared to Japanese cvs, European cvs had less elongated leaves and smaller and sweeter fruit with less total phenol and antioxidant capacities. The Japanese cvs ‘Red ace’ and the widely grown ‘Black Amber’, together with the European ‘Tuleu Dulce’, ‘BlueFre’, and the landrace ‘Asvestochoriou’ make up groups with rich dietary sources of phytochemicals. The peel tissue contained higher total phenols and antioxidant capacities compared to the flesh, while the peel/flesh ratios varied widely among the cvs (6.6-fold). The variation in the antioxidant contents was lower among the cvs calculated per serving portion (3.7-fold); yet the peel tissue contribution was equal to that of the flesh (48.6%), signifying its high nutritive value. We observed increased sweetness in the fruit in the later-harvested cultivars, while cvs with more blue- and red-colored peel generally contained higher antioxidant contents mainly in the European plums. Moreover, larger fruit sizes were positively correlated with larger and more elliptic leaf shapes. In conclusion, the significant role of the genotype and the peel tissue as a source of bioactive compounds in plums were outlined with prospects of utilization in future breeding programs.

Extracts of Common Vegetables Inhibit the Growth of Ovary Cancer Cells

“…The extract obtained from the plum pulp reduced the in vitro proliferation and viability of the A375 melanoma cells [ 22 ]. As the fruit peels have a higher content of secondary metabolites, such as polyphenols, than the pulp [ 23 , 24 ], the effects of the pulp and peel extracts of apples and plums were studied separately. However, no growth inhibition of ovary cancer cells was seen with the peel extracts.…”

Identification of Candidate Genes Associated with Pulp Color by Transcriptomic Analysis of ‘Huaxiu’ Plum (Prunus salicina Lindl.) during Fruit-Ripening

“…To date, most of the structural genes in the anthocyanin biosynthetic pathway are upregulated during the fruit development of red/green skin color mutations of pear [ 50 ]. Similarly, coordinated expression changes of ANS, DFR1, F3H, F3′H, and UFGT have also been demonstrated in differently colored plum, sweet cherry, Chinese bayberries, and other plants [ 47 , 51 ].…”

Prunus spp. Fruit Quality and Postharvest: Today’s Challenges and Future Perspectives

“…Japanese plums are available on the market in the summer and autumn months, while the European plums are usually processed into dried fruit and can be consumed throughout the year [58].…”

“…Plums have a high nutritive value, being rich in vitamins A, B1, riboflavin and are a good source in diet of sugars, proteins, carbohydrates and minerals, such as calcium, phosphorus and iron. It has multiple benefits for human health, presenting antiinflammatory, antioxidant properties, and may be related to the control of jaundice and can reduce the risk of cardiovascular diseases or cancer [31,58,59].…”