Comparative evaluation of biometrical and biochemical characteristics of three Rumex representatives: Rumex acetosa L., Rumex sanguineus L. and Rumex confertus Willd.

Increase in green vegetables popularity in nutrition and medicine promotes investigations of new cultivar and hybrid biochemical parameters. Nutritional value and antioxidant status of three Rumex representatives: Rumex acetosa L. (Krupnolistny cv.), Rumex sanguineus L. (prospect genotype) and Rumex confertus Willd. were studied. Antioxidant defense parameters (total antioxidant activity, polyphenol and ascorbic acid content) decreased in accordance to: Rumex sanguineus L. > Rumes confertus Willd. > Rumex acetosa L. Thus the ascorbic acid content in bloody dock (R. sanguineus)  reached 129 mg/100 g which was 1.48 times higher than in Russian dock (R. confertus) and 3.17 times higher than in garden sorrel (R. acetosa). The total chlorophyll content was also the highest in bloody dock (17.74 mg/g d.w.) compared to 15.88 mg/g in R. confertus and 13.07 mg/g in R. acetosa leaves. The new R. sanguineus genotype was characterized by high decorative properties and demonstrated twice higher oxalic acid content compared to R. acetosa, Krupnolistny cv., and 1.5 times higher value than in R. confertus. High decorative and medicinal value of R. sanguineus was connected to a great extent with the intensive anthocyanin accumulation reaching 7.2% and high nitrate content. The results of the present study indicate high prospects of R. sanguineus genotype utilization in landscape design, food industry and medicine.