Manipulating the antioxidant capacity of halophytes to increase their cultural and economic value through saline cultivation

摘要

Halophytes, salt-tolerant plants, are a source of valuable secondarymetabolites with potential economic value. The steady-state pools ofmany stress-related metabolites are already enhanced in halophytes whencompared with glycophytes, but growth under conditions away from theoptimum can induce stress and consequently result in changes tosecondary metabolites such as antioxidants. However, direct evidence forincreasing the concentration of valuable secondary metabolites as aconsequence of altering the salinity of the growing environment stillremains equivocal. To address this, we analysed a range of metaboliteswith antioxidant capacity (including total phenols, flavonoids,ascorbate, reduced/oxidized glutathione and reactive oxygen speciesscavenging enzymes) in seedlings and plants from different families(Amaranthaceae, Brassicaceae, Plantaginaceae and Rhizophoraceae) andhabitats grown under different salt concentrations. We show that it ispossible to manipulate the antioxidant capacity of plants and seedlingsby altering the saline growing environment, the length of time undersaline cultivation and the developmental stage. Among the speciesstudied, the halophytes Tripolium pannonicum, Plantago coronopus,Lepidium latifolium and Salicornia europaea demonstrated the mostpotential as functional foods or nutraceuticals.