The stimulation of phenolics and antioxidant activity in pea (Pisum sativum) elicited by genetically transformed anise root extract

A series of dark germination experiments demonstrate the potential of an Agrobacterium rhizogenes-transformed, high cytokinin root extract of anise (Pimpinella anisum), to stimulate phytophenolic and enhance antioxidant activity in pea (Pisum sativum) seedlings. Average shoot weight increased 40-60% after imbibing seeds for 24 h in a 1.5 to 2.0% extract of the anise root clone AR-10. Phenolic concentration was positively correlated with shoot weight, suggesting that the total phenolic content was related to seedling vigor. Antioxidant protection factor in pea shoots was also stimulated by AR-10 extracts. Free proline concentrations were 2-3 times higher in shoots collected from AR-10 treated peas versus controls. However, proline content also increased as shoot weight declined after being subjected to an overdose of AR-10 extract in 25% ethanol. G6PDH specific activity, the first committed step of the pentose phosphate pathway, was negatively associated with shoot growth and proline concentrations.