Feeding as a biotechnological approach for improvement of podophyllotoxin production in Linum album Ky. ex Boiss. cell culture

Linum album Ky. ex Boiss.، one of the endemic species in Iran، produces lignans such as podophyllotoxin (PTOX). This compound is precursor for three important anticancer drugs including etoposide، teniposide and etopophose. Chemical synthesis of these compounds is very complicated and this process is not economical. Improvementof PTOX production is possible by different strategies such as feeding، elicitation، genetic engineering، etc. Medium optimization is one of the strategies for increasing the production of secondary metabolites in cell culture. Regarding the remarkable value of PTOX as a precursor for three important anticancer drugs، in this study، the effect of different ratios of NH4+/NO3- in MS medium on cell growth and some of the of secondary metabolites including PTOX biosynthesis and phenylalanine ammonia-lyase (PAL) activity were investigated. Results indicated that the cell growth was significantly increased when treated with 2:1 ratio of NO3/NH4+. The most phenolic and flavonoid content was obtained in control culture، having minimum biomass production. The 2:1 ratio of NH4+/NO3- resulted in highest production of flavonols. The highest production of PTOX was achieved by 3:1 ratio of NH4+/NO3-. Meanwhile، the highest PAL activity was observed in 2:1 and 3:1 ratio of NO3/NH4+ and 3:1 ratio of NH4+/NO3-، respectively. Therefore، it can be concluded that changing nutrient diet is an effective factor increasing the secondary metabolites in L. album.