Characterization of phenolic compounds in prosopis strombulifera by HPLC-ESI-MS and their contribution to total antioxidant capacity.

REGINATO , MARIANA ANDREA; VARELA, CELESTE; ARSLAN, IDRIS; LUNA, MARÍA VIRGINIA

Mendoza

Congreso; XXXIV Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2016

Halophytes are known for their ability to withstand unfavourable conditions by quenching toxic ROS, since they are equipped with a powerful antioxidant system including enzymatic and non-enzymatic components as polyphenols. Prosopis strombulifera (Lam.) Benth. is a woody shrub found in high-salinity areas in central Argentina, with an interesting and contrasting growth response under NaCl and Na2SO4. NaCl caused growth stimulation (up to 500 mM) while Na2SO4 caused a significant growth reduction and toxicity symptoms. In the present study, 17 phenolic compounds were identified by HPLC-ESI-MS and their antioxidant capacity and contribution to overall antioxidant activity were calculated. Different profiles of polyphenols were found in P. strombulifera plants subjected to different salt treatments. NaCl-treated plants presented the major variety of compounds (16), with an increase in the antioxidant capacity which was similar in NaCl+Na2SO4-treated plants. In Na2SO4-treated plants, only 4 compounds were identified with a decrease in antioxidant capacity. Accumulation of flavonoids in tissues and their powerful antioxidant activity under NaCl indicates a significant role for these compounds in counteracting the oxidative damage induced by high salt concentrations, allowing optimum growth. Whereas compounds found in Na2SO4-treated plants may play a more structural role, strengthening the cell walls and increasing tissue lignification as shown in previous work.