Biotechnology Letters, Vol.42, No.7, 1237-1245, 2020
Secondary metabolites content and essential oil composition of in vitro cultures of Zingiber montanum (Koenig) Link ex A. Dietr.
Objectives To determine the secondary metabolite content, antioxidant and phenylalanine ammonia-lyase (PAL) activity as well as essential oil composition of in vitro cultures and field grown rhizomes of Zingiber montanum. Results Methyl jasmonate-treated cell cultures showed the highest total phenolic content and steroid content of 22.23 mg gallic acid equivalent/g dry weight (DW) and 41.67 mg/g DW, respectively. Callus cultures exhibited the highest tannin content (39.53 mg tannic acid equivalent/g DW) and strongest antioxidant activity (91.05% inhibition of 2,2-Diphenyl-1-picrylhydrazyl or DPPH). The highest saponin (81.76 mg/g DW) and alkaloid (113.97 mg/g DW) contents were obtained in in vitro microrhizomes induced on Murashige and Skoog (MS) medium supplemented with 6% sucrose and 5 mg/l 6-Benzylaminopurine (BAP), and MS medium supplemented with 7% sucrose, respectively. The essential oil content varied in cell cultures and microrhizomes and mainly consisted of fatty acid esters, which are precursors of many secondary metabolites. Trace amounts of terpinen-4-ol (0.21 and 0.27 mg/g) and zerumbone (0.0107 mg/g) were also detected in the in vitro microrhizomes. Conclusion The results obtained indicate the potential of in vitro cultures of Z. montanum for the production of secondary metabolites.
Keywords:Antioxidant activity;Essential oil;In vitro culture;Phenylalanine ammonia-lyase activity;Secondary metabolite;Zingiber montanum