Salicylic acid‐enhanced biosynthesis of pharmacologically important lignans and neo lignans in cell suspension culture of Linum ussitatsimum L

Abstract

Linum usitatsimum L. (flax) is a perennial herb with magnitude of medicinal and commercial applications. In the present study, we investigated the effects of salicylic acid (SA) on biosynthesis of lignans (secoisolariciresinol diglucoside (SDG) and lariciresinol diglucoside (LDG)) and neolignans (dehydrodiconiferyl alcohol glucoside (DCG) and guaiacylglycerol‐β‐coniferyl alcohol ether glucoside (GGCG)) in cell cultures of flax. Moderate concentration of SA (50 μM) enhanced biomass accumulation (10.98 g/L dry weight (DW)), total phenolic content (37.81 mg/g DW), and antioxidant potential (87.23%) to two‐fold than their respective controls after 72 h of exposure. However, higher levels of total flavonoid content (5.32 mg/g DW) were noted after 48 h of exposure to 50 μM of SA. HPLC analyses revealed that 50 μM SA, significantly enhanced biosynthesis of SDG (7.95 mg/g DW), LDG (7.52 mg/g DW), DCG (54.90 mg/g DW), and GGCG (16.78 mg/g DW), which was almost 2.7, 1.8, 3.88, and 3.98 fold higher than their respective controls after 72 h of exposure time, respectively. These results indicated that moderate concentrations of SA had significant effects on biosynthesis and productivity of lignans and neolignans in cell culture of L. usitatissimum.

Feasible Production of Lignans and Neolignans in Root-Derived In Vitro Cultures of Flax (Linum usitatissimum L.)

“…No report is present on the production of phenolic compounds in the adventitious root culture of L. usitatissimum until now. However, recently many researchers reported an improvement in the production of phenolics and flavonoids in elicited-cell cultures of L. usitatissimum [13][14][15][16]49], which also endorsed our results. Moreover, many researchers also reported that adventitious root cultures were more potent than callus cultures in the production of phenolic compounds [50].…”

“…Adventitious roots showed greater antioxidant activity than callus culture, probably due to higher production of phenolics than callus culture. Studies on the antioxidant properties of in vitro cultures of L. usitatissimum are scarce, and only a few reports are available on the antioxidant activity of its callus, hairy root cultures and cell suspension [13][14][15][16]31,32,49]. These investigators reported higher antioxidant activity in hairy root and cell suspension cultures than the callus culture of flax [31].…”

“…Following their ingestion, the intestinal bacteria metabolizes flax lignans into the mammalian lignans (enterolactone and enterodiol), reported to possibly reduce the incidence of different cancers, especially the colon, breast and prostate cancers [3]. In addition to the lignans accumulated in its seeds, flax in vitro cultures have been reported as a rich source of antioxidant neolignans (dehydrodiconiferyl alcohol glucoside, DCG and guaiacylglycerol-β-coniferyl alcohol ether glucoside, GGCG) ( Figure 1) [10][11][12][13][14][15][16].…”

“…Less is known about neolignans biosynthesis. Flax have been reported to actively produce several neolignans, in particular DCG and GGCG [10,[12][13][14][15][16], and their accumulations have been related to the expression of some DIR genes in flax hairy root cultures [19].…”

The Role of Salicylic Acid in Plants Exposed to Heavy Metals

“…From that moment, an exponential increase of manuscripts focused on SA (acting alone or in concert with other plant hormones) as a plant growth regulator, signaling molecule, as well as plant elicitor protecting plants from biotic and abiotic stress, was observed [22,23,[26][27][28][29][30][31].…”