The rise of renewable energy has unsurprisingly coincided with a greater focus on renewable energy research within the scientific community. Among the many researched, the fuel ethanol industry has taken off in recent years, and is only going to increase. But an urgent problem facing the industry is meeting the increasing demands, while dealing with detrimental losses of ethanol due to contamination. This contamination is predominantly caused by lactic acid bacteria. The lactic acid bacteria contamination significantly reduces ethanol yields in the fermentation process. To remedy this problem, the industry typically uses antibiotic treatments, which do their job well enough, but are costly and aren’t a permanent solution. In the paper “Bacteriophage-encoded
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The turbidity reduction assay results showed that the phage LambdaSa2, derived from streptococcal bacteria, demonstrated effective lytic activity in 17 out of 22 of the bacteria strains tested. LambdaSa2 was able to maintain its effectiveness when tested under the typical conditions of fermentation (pH 5.5 and less than or equal to 5% ethanol concentration), however, LambdaSa2 when tested with Lactobacillus fermentum 0605-B44 and Lactobacillus fermentum BR0315-1 showed optimal specific activity at pHs 6.5 and 7.5, as shown in Figure 3. Along with this, LambdaSa2 when tested against Lactobacillus brevis 0605-48 had very little, and in some cases even none, from 2% concentration of ethanol and upwards. Other bacteriophages tested with turbidity reduction assays, including LysA, LysA2, and LysgaY, showed similar, yet not quite as successful results. Exolytic activity was observed in 60% of the lactic acid bacteria that were tested with the aforementioned bacteriophages. Yet, these bacteriophages all demonstrated optimal specific activity at pH 5.5. Also, LysA and LysgaY both demonstrated maximum activity at 5% ethanol concentration when tested against Lactobacillus brevis 0605-48, while demonstrating an inverse effect with the two L. fermentum strains in Figure 3. These bacteriophages also were able to prove successful when put under conditions similar to fermentation. LysA2, when tested on strains of bacteria that were not lactic acid bacteria, did not demonstrate any lytic activity. Along the same lines, no lysins had successful results when tested against Escherichia coli DH5alpha and Saccharomyces cervisiae Y-2034. The authors used pH and ethanol concentration as variables because within a real fermentation environment, all these factors are slightly variable. That necessitates testing the effectiveness of lysins under a variety of
The turbidity reduction assay results showed that the phage LambdaSa2, derived from streptococcal bacteria, demonstrated effective lytic activity in 17 out of 22 of the bacteria strains tested. LambdaSa2 was able to maintain its effectiveness when tested under the typical conditions of fermentation (pH 5.5 and less than or equal to 5% ethanol concentration), however, LambdaSa2 when tested with Lactobacillus fermentum 0605-B44 and Lactobacillus fermentum BR0315-1 showed optimal specific activity at pHs 6.5 and 7.5, as shown in Figure 3. Along with this, LambdaSa2 when tested against Lactobacillus brevis 0605-48 had very little, and in some cases even none, from 2% concentration of ethanol and upwards. Other bacteriophages tested with turbidity reduction assays, including LysA, LysA2, and LysgaY, showed similar, yet not quite as successful results. Exolytic activity was observed in 60% of the lactic acid bacteria that were tested with the aforementioned bacteriophages. Yet, these bacteriophages all demonstrated optimal specific activity at pH 5.5. Also, LysA and LysgaY both demonstrated maximum activity at 5% ethanol concentration when tested against Lactobacillus brevis 0605-48, while demonstrating an inverse effect with the two L. fermentum strains in Figure 3. These bacteriophages also were able to prove successful when put under conditions similar to fermentation. LysA2, when tested on strains of bacteria that were not lactic acid bacteria, did not demonstrate any lytic activity. Along the same lines, no lysins had successful results when tested against Escherichia coli DH5alpha and Saccharomyces cervisiae Y-2034. The authors used pH and ethanol concentration as variables because within a real fermentation environment, all these factors are slightly variable. That necessitates testing the effectiveness of lysins under a variety of