The Effect of Different Concentrations of Bacillus subtilis on Spirulina platensis Growth in an Environment with Glyphosate

School Name

Spring Valley High School

Grade Level

10th Grade

Presentation Topic

Environmental Science

Presentation Type

Non-Mentored

Abstract

Red tides are a significant issue along the coasts of several countries around the world. These red tides consist of algae that grow at an expedited rate, resulting in many issues for the surrounding environment. The purpose of this experiment was to see if adding Bacillus subtilis at different concentrations would decrease Spirulina platensis growth in an environment with glyphosate. It was hypothesized that in an environment with glyphosate, a 30% B. subtilis solution would decrease S. platensis growth at a greater rate than a 0% or 15% solution because B. subtilis has the ability to degrade glyphosate and reduce the amount of nutrients available for S. platensis. To conduct this experiment, different concentrations of B. subtilis were made by diluting a bacterial solution in distilled water, respectively. Then, 5 mL of the B. subtilis solution, S. platensis, and glyphosate were added into a petri dish and placed in a dark drawer for 96 hours. Afterward, a SpectroVis spectrophotometer was used to measure the absorbance of the S. platensis in each petri dish as an indicator for colony density. The results showed that adding B. subtilis at different concentrations decreased S. platensis growth by 80.4% in the 15% solution and 88.9% in the 30% solution. A subsequent one-way ANOVA test showed the data was statistically significant since F(2, 87) = 374.46, p<0.001, which means there is enough evidence to reject the null hypothesis. The results indicate that B. subtilis was successfully able to decrease S. platenis growth by degrading the glyphosate. Therefore, it was concluded that B. subtilis could be used to reduce red tides and their harmful effects.

Location

BS 355

Start Date

3-25-2023 10:00 AM

Presentation Format

Oral and Written

Group Project

No

COinS
 
Mar 25th, 10:00 AM

The Effect of Different Concentrations of Bacillus subtilis on Spirulina platensis Growth in an Environment with Glyphosate

BS 355

Red tides are a significant issue along the coasts of several countries around the world. These red tides consist of algae that grow at an expedited rate, resulting in many issues for the surrounding environment. The purpose of this experiment was to see if adding Bacillus subtilis at different concentrations would decrease Spirulina platensis growth in an environment with glyphosate. It was hypothesized that in an environment with glyphosate, a 30% B. subtilis solution would decrease S. platensis growth at a greater rate than a 0% or 15% solution because B. subtilis has the ability to degrade glyphosate and reduce the amount of nutrients available for S. platensis. To conduct this experiment, different concentrations of B. subtilis were made by diluting a bacterial solution in distilled water, respectively. Then, 5 mL of the B. subtilis solution, S. platensis, and glyphosate were added into a petri dish and placed in a dark drawer for 96 hours. Afterward, a SpectroVis spectrophotometer was used to measure the absorbance of the S. platensis in each petri dish as an indicator for colony density. The results showed that adding B. subtilis at different concentrations decreased S. platensis growth by 80.4% in the 15% solution and 88.9% in the 30% solution. A subsequent one-way ANOVA test showed the data was statistically significant since F(2, 87) = 374.46, p<0.001, which means there is enough evidence to reject the null hypothesis. The results indicate that B. subtilis was successfully able to decrease S. platenis growth by degrading the glyphosate. Therefore, it was concluded that B. subtilis could be used to reduce red tides and their harmful effects.