Agrobacterium rhizogenes-Mediated Transformation of Crotalaria ochroleuca: Production of Flavonoids from Hairy Roots

Abstract

Crotalaria ochroleuca (Fabaceae) is rich in bioactive compounds used for nematode control. Transformed root culture allows the production of a large amount of hairy root biomass, conditioned by auxin biosynthesis-related genes integrated via the process of Agrobacterium rhizogenes infection, which is known to cause a hairy root phenotype. We transformed A. rhizogenes to increase the biomass of hairy roots and optimized the process of production of bioactive compounds. The transformed nature of hairy roots was confirmed by polymerase chain reaction, which confers kanamycin resistance. The transformed roots were cultured in full-strength in liquid media to realize the growth of hairy roots and the production of bioactive compounds. The transformed roots were grown in a culture medium supplemented with elicitors to produce total phenols, and flavonoids. Chromatographic analysis of transformed roots revealed the presence of flavonoids apigenin-6,8-C-diglucoside and luteolin-6-C-glucoside. The results were obtained by conducting physiological and biochemical studies with the flavonoids and studying the pathways that led to the production of large amounts of bioactive compounds from the hairy roots of C. ochroleuca. It was observed that the extraction of the compounds significantly affected nematodes and insect larvae, resulting in significantly high levels of economic damage to crops.