Lathraea squamaria aqueous extract as source of secondary metabolites for facile green synthesis of Ag nanoparticles with the possibility of methylene blue catalytic degradation

Physical, chemical and green synthesis procedures can all be used for the production of silver nanoparticles (AgNPs). However, plant-based green synthesis has shown outstanding results. In this study, aqueous extract of inflorescences, leaves and rhizomes of common toothwort (Lathraea squamaria L.) were prepared and their antiradical potency, polyphenols and iridoid glycosides contents were investigated. The highest content of phenolic compounds was determined in the extract from inflorescences tissues, and the highest iridoid glycosides content was in the extract from rhizomes tissues. Complex accumulation of iridoid glycosides and phenolic compounds in rhizomes tissues and total DPPH activity of the obtained extract contributed to increased abilities to reduction of AgNPs compared to inflorescences. The present research provides facile, quick and effective procedure for the green synthesis of AgNPs, which were characterized for their stability, morphological traits such as shape and size though UV-visible spectroscopy and scanning electron microscopy. The catalytic potential of green synthesized AgNPs was further tested as the degradation of methylene blue dye. This study is the first report of azo dye degradation possibility with green synthesized AgNPs from the aqueous extract of different organs of common toothwort-perennial root holoparasitic plant from the Broomrape family (Orobanchaceae).