Optimization of Regulatory Factors Affecting Biomass Growth and Crocin Production of Saffron Cells in Bioreactor

Optimizing the media for plant cell cultures, particularly regarding the types and concentrations of growth regulators, can significantly enhance biomass and metabolite production in vitro . This study examined the effects of different basal media and plant growth regulators (PGRs) on cell growth and crocin production in saffron cell suspension cultures. Various media including SH, MS, and B ₅ , in combination with specific PGRs, were tested for their efficacy in promoting cell biomass and crocin yield. Results identified that SH medium supplemented with NAA (1 mg/L) and BA (0.5 mg/L) was optimal for biomass growth, while IAA (1 mg/L) and KIN (0.5 mg/L) effectively boosted crocin production. The research continued by evaluating these factors in a bioreactor setup. For biomass enhancement, 50g of cells were inoculated into one liter of a chosen medium (SH, 3% sucrose, 0.5 mg/L BA, 1 mg/L NAA, 2.5 mM MES) with aeration at 0.5 vvm and further sucrose feeding. For crocin production, another setup used the same biomass with a medium of SH, 3% lactose, 0.5 mg/L Kin, 1 mg/L IAA, and no aeration, adjusting conditions similarly. Findings showed that cell growth index improved from 1.87 to 4.3, while crocin levels increased from 1.05 to 3.43 mg/g dry weight. Crocin content was quantified using spectrophotometry and HPLC, with image analysis employed to determine red color intensity. The study concludes that image analysis offers a cost-effective method for assessing crocin production, highlighting the effectiveness of bioreactors in enhancing both cell growth and metabolite yield.