|Interlab Study||Safety||Human Practices||Attributions|
Oil spills pose a sizeable threat to marine life and are classified as a major environmental disaster. Cleaning up after oil spills involves the use of dispersants. Chemical dispersants break down crude oil for easier biodegradation. This process depends on location and wind speed in addition to the use of mechanical human-guided skimmers that manually contain and collect oil. Current containment methods include surrounding the spill using floating booms to prevent further spread.
Sophorolipids (an example of biosurfactants) are natural dispersers that promote degradation of crude oil. The majority of sophorolipids are biodegradable and pose little toxicity to humans. Our team aims to create sophorolipids using the fermentation of the yeast Starmarella bombicola. We aim to improve sophorolipid production by disabling an enzyme (MFE-2) involved in metabolic pathways relating to sopholipids. Sophorolipids are carbohydrate-based, ampiphilic biosurfactants. The sugar (sophorose) head group is linked to the fatty acid hydrocarbon tail. They have been historically employed in oil spills to help mitigate their damaging environmental effect by accelerating crude oil degradation. Sophorolipids are the fermentation byproducts of the Starmarella yeasts, including Starmerella bombicola and Candida apicola.
Through open communication with the community at large through social media as well as direct interaction, we aim to share knowledge regarding biosurfactants to inform the public. A two-way dialogue between our research group and the community can support the exchange of information for mutual benefits. We created a postcard as part of an international postcard exchange to share our research with people around the world. As one of the 28 participating teams, our postcard reached 27 other teams worldwide to promote distribution of knowledge concerning our project. We also created a sophorolipids card for an educational biological themed card game. Details on these initiatives are available on the Collaborations page of our team wiki.
We used the yeast Starmarella bombicola to produce sophorolipids by growing it in a yeast extract and glucose-based broth supplemented with oleic acid.
Scale-Up and Deployment Issues
We expect the separation and purification of the sophorolipids to incur a larger chemical cost due to the amounts of ethyl acetate and n-hexane involved in extracting water and other impurities from the solution in addition to separating the ethyl acetate from the sophorolipids. We also expect relatively lengthy times extracting the sophorolipids using the rotovap.
Sophorolipids are an example of biosurfactants. These biologically based amphiphilic compounds are commonly used in the agricultural, pharmaceutical, and oil industries. The environmental benefits of biosurfactants include their low toxicity, biodegradability, and ability to enhance biodegradation and solubilization of low solubility compounds. Biosurfactants can increase the solubility and microbial biodegradability of hydrocarbons found in petroleum, reducing their devastating effects in the environment when spilled. This use of biosurfactants as dispersants applies to both aquatic environments and soil, where oil can hinder the growth of plants.
Our project does not include testing on animals/human subjects to evaluate potential therapeutic properties of sophorolipids. Our work utilizes Starmarella bombicola (yeast) as the biological chassis to be employed as well as the organic byproducts of its fermentation. The yeast’s byproducts possess low toxicity. We also conducted the standard InterLab study using DH5-alpha E. coli.
Starmarella bombicola is also known as Candida bombicola, though Starmarella bombicola is now the preferred name. This organism is a fungus that is more specifically known as an example of a yeast. The strain has been managed in a biosafety level 2 laboratory with proper sterilization and containment procedures employed. Such devices include autoclaves, biosafety cabinets, personal protective equipment, and limited lab access. Lab safety also includes proper handling of the yeast when undergoing enzymatic modifications.
Laws and Regulations
There are no current laws and regulations that specifically address the production or deployment of sophorolipids in the country of development. Our project does not include specific evaluation of the potential therapeutic uses of sophorolipids, and we are not marketing sophorolipids as a drug. Our project does not use sophorolipids to diagnose, treat, cure, or prevent any disease. Liability laws, contingency plans, relief funds, and oil spill control mechanisms guide the responses to oil spills.
Our project involves the use of sophorolipids that are biodegradable. The yeast Starmarella bombicola is not recognized as a biological agent associated with the transmission of a disease.