PARENT SESSION
Poster Session 37: Toxicology and Disease
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Using amino acids to induce hyper-accumulation of arsenic and molybdenum in Helianthus argophyllus.

Baquera, Noemi^*,1, ¹ The University of Texas at El Paso, El Paso, Tx

ABSTRACT- Phytoremediation is the engineered use of plants to clean up and sequester contaminants from the soil, this renders contaminates available for harvesting and safe disposal. Some plants are naturally capable of accumulating metals in their root and shoot system; however, is it possible to induce hyper-accumulation in plants? The ideal plant would have to be readily available in South Texas, contain a large biomass, and have a rapid growth. So for this experiment the silver leaf sunflower, Helianthus argophyllus was used to determine whether foliar applied amino acids, such as cystine and glutamine, promote hyper-accumulation of arsenic (As) and molybdenum (Mo). For comparison, this experiment was also done using Indian mustard, Brassica juncea (L.) Czern, which is a known hyper-accumulator of metals such as Pb and Zn. For this experiment there were four different treatment groups which were kept in a growth chamber with controlled settings. Treatments consisted of a 600 mL solution with 1 part Arsenic, 1 part Molybdenum, 2 parts Hoaglands, and DI water. After four weeks of treatment, leaf samples were taken from each experimental group for chemical analysis. Each sample was ground up and ran through an HPLC to determine the concentration of low molecular weight thiols. Preliminary data suggests that the plants were able to tolerate the As and Mo levels, however the tolerance was due to an exclusion of the metals instead of hyper-accumulation. The plants that were not treated with the amino acids showed signs of poisoning earlier in the experiment. The treatment seemed to prolong the life of the plant, but it did not allow the plant to sequester the metals safely. The original hypothesis was rejected but results support a possible treatment for resistance or the ability to minimize the effect of high levels of Arsenic and Molybdenum.

Key words: Phytoremediation, Helianthus argophyllus, Hoaglands, hyper-accumulation