Title

The effect of feed composition on biological hydrogen production in Saccharomyces cerevisiae

Author(s)

Noah V. Fechter

School Name

Spring Valley High School

Grade Level

11th Grade

Presentation Topic

Microbiology

Presentation Type

Non-Mentored

Abstract

Common commercial means of producing hydrogen energy have been deemed too costly to compete with non-renewable energy sources like gasoline and too energy intensive to be environmentally friendly. Biological hydrogen production (BHP) presents a promising area of research for generating bioenergy. BHP may be conducted by dark or photo-fermentative organisms, and these systems can be used in conjunction, with the waste products of photo-fermentative BHP being converted by dark-fermentative organisms to usable compounds.

This experiment seeks to further ascertain feed composition that results in the greatest usable hydrogen yield in Saccharomyces cerevisiae by measuring the effect of feed composition on change in local pH from S. cerevisiae metabolism. pH serves as an identifier for usable hydrogen yield as increased acidity indicates increased free hydrogen concentration. S. cerevisiae was cultured in sabouraud dextrose, lactose, and nutrient broth media, with a control sample of each media without culturing. It was hypothesized that if S. cerevisiae is cultured in sabouraud dextrose, lactose, and nutrient broth media, the pH of each solution would decrease, with sabouraud dextrose broth resulting in the greatest decrease in pH.

The pH of each culture solution was recorded after growth, and the difference between each culture solution’s pH and uncultured solutions was calculated. At α = 0.05, one-way ANOVA of change in pH by media type returned p < 0.01, indicating significant variance between media types. Tukey post-hoc testing suggests no significant difference between sabouraud dextrose and lactose broth, but a difference between these groups and nutrient broth. Inferring from values for mean change in pH, Saccharomyces cerevisiae appears to significantly yield the greatest concentration of usable hydrogen when cultured in nutrient broth.

Start Date

4-11-2015 10:00 AM

End Date

4-11-2015 10:15 AM

COinS
 
Apr 11th, 10:00 AM Apr 11th, 10:15 AM

The effect of feed composition on biological hydrogen production in Saccharomyces cerevisiae

Common commercial means of producing hydrogen energy have been deemed too costly to compete with non-renewable energy sources like gasoline and too energy intensive to be environmentally friendly. Biological hydrogen production (BHP) presents a promising area of research for generating bioenergy. BHP may be conducted by dark or photo-fermentative organisms, and these systems can be used in conjunction, with the waste products of photo-fermentative BHP being converted by dark-fermentative organisms to usable compounds.

This experiment seeks to further ascertain feed composition that results in the greatest usable hydrogen yield in Saccharomyces cerevisiae by measuring the effect of feed composition on change in local pH from S. cerevisiae metabolism. pH serves as an identifier for usable hydrogen yield as increased acidity indicates increased free hydrogen concentration. S. cerevisiae was cultured in sabouraud dextrose, lactose, and nutrient broth media, with a control sample of each media without culturing. It was hypothesized that if S. cerevisiae is cultured in sabouraud dextrose, lactose, and nutrient broth media, the pH of each solution would decrease, with sabouraud dextrose broth resulting in the greatest decrease in pH.

The pH of each culture solution was recorded after growth, and the difference between each culture solution’s pH and uncultured solutions was calculated. At α = 0.05, one-way ANOVA of change in pH by media type returned p < 0.01, indicating significant variance between media types. Tukey post-hoc testing suggests no significant difference between sabouraud dextrose and lactose broth, but a difference between these groups and nutrient broth. Inferring from values for mean change in pH, Saccharomyces cerevisiae appears to significantly yield the greatest concentration of usable hydrogen when cultured in nutrient broth.