Improvement of Nutraceutical Value of Parsley Leaves (Petroselinum crispum) upon Field Applications of Beneficial Microorganisms

Parsley (Petroselinum crispum) is an important aromatic herb that has gained importance in food and cosmetic industry, and it is used as medicinal plant due to the presence of compounds with biological activity. Several studies have demonstrated antioxidant, antimicrobial or cancer chemopreventive activity of different parts of parsley plants. We showed that the nutritional value of parsley leaves can be improved by treatments with beneficial microorganisms on the field crop. Streptomyces fulvissimus strain AtB-42 and Trichoderma harzianum strain T22 were applied, as singly or in combination (microbial consortium), at transplanting and two weeks later. After harvesting, plants were subjected to metabolomic analysis by LC and GC-MS. Spectrometric analysis resulted in the identification of seven polar metabolites. Results showed a significant difference in relative abundance of these metabolites among treatments. The AtB-42 application, alone or in combination with T22, induced the accumulation of petroselinic acid, while T22, alone or in combination, induced the accumulation of xanthotoxol/bergaptol and its derivative xanthotoxin/bergapten. The microbial consortium increased the accumulation of capsanthone compared to single treatments. No statistically relevant differences were found for the volatile fraction. It can be concluded that S. fulvissimus and T. harzianum significantly induced metabolic profile change of parsley and the accumulation of metabolites with nutraceutical value.