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The anticancer compound podophyllotoxin and other related lignans can be produced in Linum album in vitro cultures, although their biosynthesis varies according to the degree of differentiation of the plant material. In general, L. album cell cultures do not form the same lignans as roots or other culture systems. Our aim was to explore how the lignan-producing capacity of organogenic cell masses is affected by the conditions that promote their formation and growth. Thus, L. album biomass obtained from plantlets was cultured in darkness or light, with or without the addition of plant growth regulators, and the levels of podophyllotoxin, methoxypodophyllotoxin and other related lignans were determined in each of these conditions. The organogenic capacity of the cell biomass grown in the different conditions was studied directly and also with light and scanning electronic microscopy, leading to the observation of.several somatic embryos and well-formed shoots. The main lignan produced was methoxypodophyllotoxin, whose production was clearly linked to the organogenic capacity of the cell biomass, which to a lesser extent was also the case for podophyllotoxin., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Linum album is a herbaceous plant with medical interest due to its content of podophyllotoxin (PTOX), an aryltetralin lignan with cytotoxic activity. Previous studies in our laboratory showed that cell suspension cultures of L. album produced more PTOX than methoxypodophyllotoxin (6-MPTOX), both lignans being formed from the same precursor after divergence close to the end of the biosynthetic pathway. In contrast, the hairy roots produced more 6-MPTOX than PTOX. Taking into account this variability, we were interested to know if the lignan profile of an in vitro PTOX-producing L. album plant changes according to the biotechnological system employed and, if so, if this is due to cell dedifferentiation and/or transformation events. With this aim, we established four biotechnological systems: (1) Wild type cell suspensions, (2) transformed cell suspensions, (3) adventitious roots and (4) hairy roots. We determined the production of four aryltetralin lignans: PTOX, 6-MPTOX, deoxypodophyllotoxin (dPTOX) and β-peltatin. The results show that in vitro plantlets, WT cells and transformed cells predominantly produced PTOX, production being 11-fold higher in the plantlets. Otherwise, the adventitious and hairy roots predominantly produced 6-MPTOX, the adventitious roots being the most productive, with MPTOX levels 1.58-fold higher than in transformed roots. We can infer from these results that in the studied plants, cell differentiation promoted the formation of 6-MPTOX over PTOX, while transformation did not influence the lignan pattern., (Copyright © 2018 Elsevier GmbH. All rights reserved.)