Effect of fungal elicitor and heavy metals on the production of flavonol glycosides in cell cultures of Ginkgo biloba

Abstract

The effect of fungal elicitor and heavy metal salts on the production of flavonol glycosides in cell cultures of Ginkgo biloba was investigated. Among the fungi tested, Trichoderma longibrachiatum ATCC 52326 was found to be the most efficient in the production of flavonol glycosides. Kaempferol production from the elicited callus increased tenfold as compared to the unelicited callus, while quercetin concentration of elicited cells was nine-fold higher than that of unelicited cells in suspension cultures. The maximum quercetin concentration of 0.362 mg/l was obtained in 1.25 mg/l of the homogenate elicitor. Among the heavy metal salts tested, CuSO 4 showed a significant effect on quercetin accumulation, reaching to the concentration of 0.526 mg/l. Quercetin concentration increased to a maximum of 12-fold in response to CuSO 4 treatment as compared to that of untreated cells. The phenylalanine ammonia-lyase (PAL) activity and flavonol glycosides production simultaneously increased for 5 days of culture after fungal elicitor feeding, and their contents showed the same proportional patterns during the culture period. In contrast, PAL activity of cell cultures treated with CuSO 4 was almost constant during the culture period, although quercetin production increased remarkably.