Enhanced production of alizarin type anthraquinone dye achieved through biotransformation of Oldenlandia umbellata L. using different strains of Agrobacterium rhizogenes
摘要
Hairy roots (HRs) produced by Agrobacterium rhizogenes infection on plants are an excellent system for producing economically valuable metabolites. Oldenlandia umbellata L. is a source of an important textile dye, anthraquinone (AQ). The current study focuses on optimizing different parameters for the successful transformation of O. umbellata by four strains of A. rhizogenes; A4, R1000, MTCC 2364, and MTCC 532. In vitro-produced micro shoots were more suitable for HR induction than leaves. Optical Density (OD) value (0.7) produced the highest transformation frequency (%) in MTCC 2364, R1000, A4 and strain MTCC 532 showed HR root induction at a lower OD (0.5). Acetosyringone (AS) concentrations greatly influenced the transformation frequency (TF%).100 µM AS treatment caused 86.66% transformation in A4 infected explants, and 400 µM AS treatment produced a higher transformation in R1000 (76.6%) and MTCC 2364 (85%). MTCC 532 was successful (88.3%) in transforming explants when 200 µM AS was used. The addition of 2.9 mM calcium chloride (CaCl2) had an inhibitory role in HR induction by all strains. MTCC 532-derived HRs showed superiority in biomass (4.8 g fresh weight) and AQ yield (3.34 mg/g dry weight) over others. Data from five subcultures confirmed the stability in fresh weight, dry weight, and AQ yield of HRs produced by different strains. This work optimized different parameters for the biotransformation of O. umbellata by four strains of A. rhizogenes strains, to enhance anthraquinone production. MTCC 532 demonstrated the highest transformation efficiency, biomass, and AQ yield.