Chemical and Engineering News Abstracts

Scott Humason

Chem 241: MWF: 8:30-9:50

Chemical and Engineering News Abstracts

Specialty Chemicals: Environmental Challenges Drive Alternatives
Phthalate Esters are an established and cost effective plasticizer that is used to make polyvinyl chloride (PVC) flexible. Phthalate esters are one of the most scrutinized chemicals permitted on the market today. Environmentalists argue that phthalate causes reproductive problems and damage sexual development in neonatal infants. Industrial groups argue that there is no correlation between adverse health issues and the use of phthalate. Alternative plasticizers do exist, however, none of them meet the broad range of applications as they are for very specific uses and come at in increased cost. Because of this cost increase, it is not expected for alternatives to be heavily sought after until a ban on phthalate is imposed.

Bacterial Conversations
Conversations between bacteria have been documented as a natural phenomenon. These single cell organisms are thought to communicate their needs to other like species of bacteria as a means of getting what they are not locomotivly able to provide on their own. Bacterial conversations are defined as quorum sensing and are made up of chemicals called autoinducers. An example of this behavior is a bacteria's ability to listen to autoinducers which turn on or off the genes of the bacteria to act in solidarity or in a group. When a minimum population size has been met, they will function as a group. The squid has developed an symbiotic relationship with these bacteria as seen by luminescence. In exchange for food and shelter, V.fisheri will produce luminescent proteins when signaled by the squid. The luminescent proteins will in turn allow the light needed for the squid to hunt and thus complete the cycle to feed and house the bacteria.