Enhanced accumulation of high-value deoxymiroestrol and isoflavonoids using hairy root as a sustainable source of Pueraria candollei var. mirifica

Pueraria candollei var. mirifica (PM), a rejuvenating herb of Thailand, has been applied efficaciously to relieve symptoms of estrogen deficiency in various clinical trials. However, there is a shortage of the natural source of the plant because of high demand. A clone of hairy root was produced by genetic transformation of T-DNA from an Agrobacterium rhizogenes ATCC15834 strain. An in vitro elicitation strategy for PM hairy root was successfully established. The hairy root of PM produced a high amount of deoxymiroestrol [71.9 ± 4.67–77.9 ± 6.63 µg g−1 dry weight (DW)] and isoflavonoids (6.57 ± 0.044–7.05 ± 0.534 mg g−1 DW). These amounts are higher than that obtained from the root of its parental intact PM, which contained deoxymiroestrol (15.41 ± 0.71 µg g−1 DW) and isoflavonoids (3.45 ± 0.21 mg g−1 DW). Interestingly, the treatment of the hairy root with methyl jasmonate (50–200 µM) increased the accumulation of deoxymiroestrol (113 ± 11.4–245 ± 12.0 µg g−1 dry weight) and isoflavonoids (9.94 ± 0.365–16.49 ± 0.466 mg g−1 DW). Therefore, this approach markedly improved the production of PM phytoestrogens. The field cultivation of PM takes at least 1 year to produce a substantial amount of deoxymiroestrol and isoflavonoids; moreover, there are geographical and seasonal variations in phytoestrogen content, influencing the limited supply and quality of PM materials. Therefore, this system of PM hairy root culture and elicitation is quite simple and effective for the production of useful phytoestrogens for phytochemical and cosmeceutical industries. Additionally, this process can be scaled up to the industrial level as a sustainable source of PM.