Phytoremediation of Nitrate and Bisphenol a by Scindapsus Auresus (Lindl. & Andre) Engl.

Abstract

Scindapsus aureus (Lindl. & Andre) Engl. plants were assessed for their ability to phytoremediate nitrate (NO3-) and bisphenol A (BPA) from water. NO3- is one of the two forms of inorganic nitrogen introduced excessively into the environment via anthropogenic sources and NO3- pollution is a widespread problem faced by countries all around the world. BPA is also well-known water pollutant in urban cities; it is hazardous as it can act as an endocrine-disrupting chemical.<br><br>S. aureus plants were partially submerged in water containing 0, 20, 50, 100 and 200 mg/L NO3- for a period of eight weeks. By the end of eight weeks, S. aureus plants were able to completely remove NO3- from 20, 50, 100 mg/L NO3--containing water, and more than 80 % of NO3- from 200 mg/L NO3--containing water. Physiological and biochemical tests carried out showed that S. aureus plants were also able to tolerate the high initial NO3- concentrations. Nitrogen-deficiency symptoms such as decreases in chlorophyll concentration, photosynthetic efficiency of PSII, total soluble protein concentration, as well as increased oxidative stress and antioxidant enzyme activities, were only observed when NO3- levels decreased towards the end of the eight-week study. The activity of nitrate reductase changed, as a result of changes in environmental factors aside from NO3- concentrations.<br>When exposed to water spiked with BPA (0, 50, 100 and 250 B5M) over a period of seven days, S. aureus plants were able to completely remove BPA from 50 and 100 B5M BPA-containing waters, and 50% of BPA from 250 B5M BPA-containing water. Exposure of S. aureus plants to BPA resulted in decreases in chlorophyll concentration and photosynthetic capacity; they also showed an oxidative burst. However, by the end of the study, the plants were able to develop tolerance to BPA, shown by the upregulation of activities of antioxidant enzymes (ascorbate peroxidase, glutathione reductase, superoxide dismutase and guaiacol peroxidase) and recovery of chlorophyll levels. <br>In all, the results obtained indicated that S. aureus could be a promising plant species to use for the efficient phytoremediation of NO3- and BPA.