Comparative evaluation of antioxidant status and mineral composition of Diploschistes ocellatus, Calvatia candida (rostk.) Hollós, Battarrea phalloides and Artemisia lerchiana in conditions of high soil salinity

Abstract

Natural reserves play a fundamental role in maintaining flora and fauna biodiversity, though biochemical characteristics of such ecosystems have been studied in an extremely fragmentary way. For the first time mineral composition and antioxidant status of three systematic groups of organisms, lichens (Diplischistes ocellatus), mushrooms (Calvatia candida and Battarrea phaloides) and wormwood (Artemisia lerchiana), are described at the territory of Bogdinsko-Baskunchak Nature Reserve (the North-Eastern part of Astrakhan region, Russia), characterized by remarkable oxidant stress, i.e., high salinity and solar radiation, and water deficiency. Through ICP-MS, it was determined that scale lichen D. ocellatus accumulated up to 10-15% Ca, 0.5% Fe, 15 mg kg-1 d.w. iodine (I), 54.5 mg kg-1 Cr and was characterized by low levels of Na, K and P (873, 1389 and 302 mg kg-1 d.w., respectively). Battarrea phalloides demonstrated anomalously high concentrations of B, Cu, Fe, Mn Se, Zn, Sr and low Na levels, contrary to Calvatia candida mushrooms accumulating up to 10850 mg kg-1 Na and only 3 mg kg-1 Sr. The peculiarity of A. lerchiana plants was the high accumulation of В (22.23 mg kg-1 d.w.), Mn (57.48 mg kg-1 d.w.), and antioxidants (total antioxidant activity - 68.6 mg GAE g-1 d.w.; polyphenols - 21.0 mg GAE g-1 d.w. and proline - 5.45 мМ g-1 d.w.). Diplischistes ocellatus and Calvatia candida demonstrated the lowest antioxidant status: 3.6-3.8 mg GAE g-1 d.w. total antioxidant activity, 1.73-2.10 mg GAE g-1 d.w. polyphenols and 2.0-5.3 mg g-1 d.w. proline. Overall, according to the elemental analysis of lichen from Baskunchak Nature Reserve and Southern Crimean seashore, the vicinity of Baskunchak salty lake was characterized by increased environmental levels of Cr, Si, Li, Fe, Co, Ni and Са.