Phytochemical variability during vegetation of Chamerion angustifolium (L.) Holub genotypes derived from in vitro cultures

Abstract

The purpose of the study was to evaluate Chamerion angustifolium (L.) Holub genotypes for preliminary selection and further breeding programs aimed at obtaining a suitable industrial form for the pharmaceutical applications. Clonally propagated plants representing 10 genotypes of Ch. angustifolium were regenerated under in vitro conditions, hardened and planted in the field. Studies included an evaluation of shoot proliferation, phytochemical assessment of in vitro and ex vitro plants as well as investigations of intraspecies variability regarding four phenological stages: vegetative, beginning of blooming, full blooming, and green fruit phases. Quantitative and qualitative analyses of bioactive compounds were performed using high-performance liquid chromatography coupled with diode array detector and tandem mass spectrometer (HPLC–DAD–MS/MS) and high-performance liquid chromatography (HPLC) methods. The efficiency of shoot multiplication varied between genotypes from 8.12 to 21.48 shoots per explant. A high reproduction rate (> 20 shoots per explant) was recorded for four lines (PL_45, PL_44, PL_58, DE_2). Plants grown in vitro synthesized oenothein B (11.2–22.3 mg g−1 DW) and caffeic acid derivatives. Plants harvested from field contained the full spectrum of polyphenols characteristic for this species, and oenothein B and quercetin 3-O-glucuronide were the most abundant. The maximal content of oenothein B was determined in the vegetative phase of fireweed, while some flavonoids were found in the highest amount in full blooming phase. The results of analysis of variance indicated significant differences among genotypes in oenothein B, 3-O-caffeoylquinic acid and flavonoids accumulation in four phenological phases. PL_44 plants were characterized by high content of oenothein B and quercetin 3-O-glucuronide as well as a relatively high level of other flavonoids. Based on our phytochemical and micropropagation studies, PL_44 genotype was the best candidate for early selection and further breeding programs.