Celebrating the 75th Anniversary of the ACS of Puerto Rico 

University of Puerto Rico  

Mayagüez Campus  

Chemistry Department  

Departmental Seminar  

Celebrating the 75^th. Anniversary of the ACS of Puerto Rico    

by    

Ms. Jomarys González  

UPRM PhD. Candidate  

Friday, December 2^nd , 2022    

10:30 am  

Effect of hydrogen sulfide on the uptake of Cadmium 

by Leucaena Leucocephala 

Cadmium (Cd) levels in agricultural soils are increasing because of industrial expansion and fertilizers use. There are few plants which tolerate heavy metals particularly Cd. NaHS as hydrogen sulfide (H₂S) donor, plays a significant role in Cd tolerance by plants reducing its toxicity. In the present research, Leucaena leucocephala plants were grown in a hydroponic system for 25 days, and then exposed for 3 days to Cd concentrations of 5, 10, and 15 ppm to determine their potential use in Cd remediation. The effect of NaHS in Cd and macro/micronutrient uptake, as well as some physical and chemical parameters in L. leucocephala plants were evaluated. Plants were exposed to 5 ppm of Cd and NaHS at 1, 10, and 100 μM for 3 days. Inductively Coupled Plasma Optical Emission Spectrometry (ICP/OES) was used to quantify Cd content and macro/micronutrients in plant tissues. Results show a significant increase in Cd uptake by plant tissues (Fisher ́s LSD) as Cd levels in the media increase. Highest Cd content (830 ± 20 mg/kg) was found in stems of plants exposed to 15 mg/L Cd. Ca, Mg, K, Zn, and Mn decreased as Cd concentration increased in the media. A significant difference (Fisher ́s LSD) in radicle length was observed in plants exposed to Cd and NaHS. Addition of NaHS to the media resulted in a significant increase in Cd uptake by root as NaHS concentration in media increased. Maximum Cd uptake (7670 ± 102 mg/kg) was found in roots of plants exposed to 100 μM of NaHS. A significant reduction in CAT activity was observed in root system due to Cd concentration inside plant tissues. Results suggested that NaHS helps to decrease the toxic effect of Cd on the growth and development of plants.