RITA仮浸漬系で培養したBENTH.の成長および二次代謝物蓄積に及ぼすスペルミンおよび窒素欠乏の影響

Influence of spermine and nitrogen deficiency on growth and secondary metabolites accumulation in Benth. cultured in a RITA temporary immersion system.

• Elizabeth Rubio-Rodríguez
• Alma Rosa López-Laredo
• Virginia Medina-Pérez
• Gabriela Trejo-Tapia
• José Luis Trejo-Espino

抄録

窒素欠乏（ND）ストレス下で生育する新芽に及ぼす外因性スペルミン（SPM）の影響を評価した。仮浸漬系で培養した新芽は、以下の4つの実験処理を行った。(1)対照、(2)外因性SPM、(3)ND、(4)ND+SPMであった。その結果，ND+SPM処理ではND処理（4.2±0.5cm）に比べて，6.3±0.5cmの伸長が認められた。総クロロフィル含量は対照とSPM処理で同程度（0.41μgmg FM）であり、総フェノール含量はND+SPM処理で21日目に最も高い値が検出された（84.1±0.05GAE g DM）。ND+SPM処理では、フェニルアラニンアンモニアリアーゼ活性がND処理よりも早く上昇し、21日目に最大値を示した（3.9±0.2μmol E-CIN hmg蛋白質）。また、ND処理及びND+SPM処理では、対照と比較して、根部及び空中部の両方で二次代謝物の含有量が増加した。また、SPMとND+SPMでは、根部でケルセチン含量が増加した（対照の4.3倍）。この結果から，SPMはNDによるダメージを部分的に打ち消し，貴重な生理活性化合物の含有量を増加させることが明らかになった。

The effect of exogenous spermine (SPM) on shoots developing under nitrogen deficiency (ND) stress was evaluated. Shoots cultivated in a temporary immersion system were subjected to four experimental treatments: (1) control; (2) exogenous SPM; (3) ND; and (4) ND+SPM. Shoots were longer in the ND+SPM treatment (6.3 ± 0.5 cm) than in the ND treatment (4.2 ± 0.5 cm). The total chlorophyll content was similar in the control and SPM treatments (0.41 µg mg FM) and the highest values of total phenolic content were detected at 21 days in the ND+SPM treatment (84.1 ± 0.05 GAE g DM). In the ND+SPM treatment, the phenylalanine ammonia lyase activity increased earlier than in ND treatment, and reached its maximum at day 21 (3.9 ± 0.2 µmol E-CIN h mg protein). Compared with the control, the ND and ND+SPM treatments resulted in increased secondary metabolites contents in both root and aerial parts. The strongest effect was in the roots, where the SPM and ND+SPM treatments both resulted in increased quercetin content (4.3-fold that in the control). Our results showed that SPM partially counteract the damage caused by ND and results in increased contents of valuable bioactive compounds.

© 2019 The Authors. Engineering in Life Sciences published by Wiley‐VCH Verlag GmbH & Co. KGaA.