Identification of Oxidative Damage in Bamboo Plants exposed to Chromium

1. Maya Rudolph Alabama A&M University REU-China Research and Cultural Experience 本科生研究經驗 Identification of Oxidative Damage in Bamboo Plants exposed to Chromium Mentors: Dr. Malinda Gilmore-AAMU Dr. YinFengXie and Dr. Yulong Ding-NFU

2. Through industrial manufacturing, waste disposal, and human agricultural activities, plants have been exposed to excessive amounts of heavy metals, leading to toxic conditions. Heavy metal pollution to water and soil poses a major environmental problem. Introduction

3. Chromium is a natural component in soil, with a number of heavy metals, being required by plants as micronutrients. Chromium concentrations in contaminated soils result in a decrease of plant growth and development, and negatively affects the plant’s photosynthesis. Introduction (CHROMIUM)

4. Heavy metals cannot be destroyed or degraded but are only transformed from one oxidation state to another. Remediation of heavy metal contamination in soils is difficult. Studies have shown of some methods used for the remediation of heavy metals in plants. Thus, these methods has caused large destruction of soil structure and fertility, therefore new experimental phytoremediation strategies are necessary. Introduction (phytoremediation)

5. Silicon plays a significant role in soil formation processes. Silicon is a plant nutrition that reinforces the plant’s protection from diseases and containments. INTRODUCTION (SILICON)

6. Malondialdehyde (MDA) • widely used marker of oxidative lipid injury whose concentration varies in response to biotic and abiotic stress. • MDA is the main product of membrane lipids when plants are subject to several stress levels. • Chlorophyll content • an index used to diagnose the plant nutrients’ status or damage of a plant. Various Assays

7. Objective • To test the oxidative damage of IndocalamusBarbatus McClure Bamboo species exposed to chromium (Cr). • To develop the potential IndocalamusBarbatus McClure Bamboo species for phytoremediation activity, Silicion (Si) was tested to restore the balance in the plant.

8. The IndocalamusBarbatus McClure Bamboo species was planted by the Nanjing Forestry University graduate students last semester of September 2012. The bamboo was planted in 1 kg of dry soil. The students observed and allowed the plants to grow for a time span of 60 days. Methods

9. Chromium Exposure: • Control = O g of Chromium (5 pots) • Experiment #1= 200 g of Chromium (5 pots) • Experiment #2 = 400 g of Chromium (5 pots) • Experiment #3= 800 g of Chromium (5 pots) • The bamboo plants were watered twice daily with 150 mL of water. Methods

10. Silicon Exposure to 800 g of Chromium: • Control= O g • Experiment #1 = 100g of Silicon • Experiment #2 = 300 g of Silicon • Experiment #3 = 500 g of Silicon • The bamboo plants exposed to Silicon were watered twice daily with 150 mL of water. Methods (phytoremediation)

11. Methods (Sample Preparation) • Sample Preparation: • Retrieve 0.2 g of Bamboo sample. • Grind sample using Quartz Sand and add 5mL 7.5% buffer solution. • Centrifuge sample for 15 minutes at 6,000 rpm using a AnkeTGL-16G centrifuge. • Retrieve supernatant and use for various assays (i.e., MDA)

12. Measure 3 mL of tert-butyl alcohol (TBA) into a clean 15 mL test tube. Add 2 mL of Bamboo sample to the test tube. Heat the mixture for 15 minutes in a hot water bath at 100°C. Centrifuge at 6,000 rpm for 15 minutes in Anke TGL-16G. Place 2mL of the mixture into a cuvette and measure absorbance at 532nm, 450nm and 600nm using a 2802 UV/VIS Spectrophotometer, place 2mL of the mixture in a cuvette. Malondialdehyde (MDA) The formula to calculate the data of MDA:

13. Chlorophyll Content • To measure the chlorophyll content of the bamboo species, use a digital chlorophyll meter.

14. Results Table 1: The effect of chromium stress on MDA in bamboo. Table 2: The effect of silicon on MDA in bamboo exposed to 800 g of chromium.

15. Results Figure 1: Shows the increase in MDA content with exposure to 800 g of chromium which indicated damage , then shows the decrease in MDA content with the exposure of silicon, which indicate that it protected the bamboo from the oxidative damage caused from the exposure of 800 g chromium.

16. Results Table 3: The effect of chromium stress onchlorophyll content in bamboo. Table 4: The effect of silicon on chlorophyll content in bamboo exposed 800 g of chromium.

17. Results Figure 2: Shows the decrease in chlorophyll content with exposure to 800 g of chromium which indicated damage , then gradually shows increase in chlorophyll content with the exposure of silicon, which indicate that it protected the bamboo from the oxidative damage caused from the exposure of 800g of chromium.

18. Bamboo Excess From Chromium Silicon to release the damage from Chromium Comparisons

19. The bamboo being exposed to chromium caused oxidative damage. The bamboo exposed to silicon proved that silicon protected the bamboo against the oxidative damage caused by chromium exposure. Conclusion

20. Jiang, Li, Gangrong Shi, Yulong Ding, Laiqing Lou, and QingshengCai. "Differential Responses of Two Bamboo Species to Excess Copper." (n.d.): n. pag. Web.  Jing, Yan-de, Zhen-li He, and Xiao-e Yang. "Role of Soil Rhizobacteria in Phytoremediation of Heavy Metal Contaminated Soils." Http://www.ncbi.nlm.nih.gov/pmc/articles/PM C1810380/. Journal of Zhejiang University, 8 Mar. 2007. Web. References

21. Dr. Malinda Gilmore, AAMU Mentor and Academic Advisor Dr. YingfengXie and Dr. Yulong Ding, NFU Mentors Graduate Students: GhassemEmamverdiyan and Gao Yung Dr. Zhen Wang Dr. Elica Moss Nanjing Forestry University Alabama A&M University National Science Foundation Acknowledgements

22. 我的文化体验 My Cultural Experience

23. Shanghai

24. YUMMMM...

25. Nanjing Forestry University

26. Yangzhou

27. Beijing

28. Xi’an

29. Lights, Camera, Ni hao