The Evaluation of Isatin 3-Hydrazone Derivatives toward Biofilm Regulation

In the current methodology of fighting infections, antibiotics are used to eliminate the invading bacteria. A result of this process is constantly evolving antibiotic-resistant bacteria. If we hope to be more effective at preventing disease, we must shift the way we view microbial treatment. One novel method of preventing bacterial proliferation is the modulation of biofilm. Many bacteria can produce a biofilm; an extracellular substance that provides protection and antibiotic resistance to the bacteria. Attacking this biofilm and allowing the body’s natural defenses to clear out the bacteria is one promising way to treat bacterial infections while avoiding adaptive bacterial mutation. Isatin has been shown to regulate biofilm and thus exhibits properties similar to quorum sensing molecules. Additionally, isatin derived from indole which is a known quorum sensing molecule. Previous studies have shown that hydrazone and oxime derivatives of isatin have antimicrobial properties, which make them targets of interest in testing the ability of isatins to regulate biofilms. Within this study, a library of these compounds was created and tested against E. coli, P. aeruginosa, S. aureus to determine the OD600 correlation, minimum inhibitory concentration and the effect the compounds have on biofilm formation. For E. coli it was found that a compound was found to inhibit while others promoted. For P. aeruginosa, it was found that a compound was found to inhibit biofilm production, while two others were found to be promoters. Compounds were found to be biofilm inhibitors for S. aureus, while a compound was found to be a promoter

Cooperative Conservation: Determinants of Landowner Engagement in Saving Endangered Species

This paper analyzes surveys of private landowners to identify factors that determine landowner engagement in the conservation of endangered species. The Endangered Species Act’s approach to engaging landowners is generally punitive and restricts action on private land that endangered species inhabit. Existing research suggests that the Endangered Species Act’s punitive approach creates perverse incentives that result in poor conservation outcomes. Because engaging private landowners is crucial to the success of preserving species, this research seeks to identify better approaches to encourage private landowners to conserve endangered species. The authors conduct comparative analysis of relevant papers that examine private landowners’ attitudes toward conservation. Their analysis suggests that landowners are more willing to engage in conservation of endangered species when the approach is less punitive and more cooperative and when the effort comes from more local levels

Disconnecting the Estrogen Receptor Binding Properties and Antimicrobial Properties of Parabens through 3,5-Substitution

Commercially utilized parabens are employed for their antimicrobial properties, but a weak binding to the estrogen receptor alpha (ER_α) may lead to breast cancer in some applications. Modification of the paraben scaffold should allow for a disconnection of these observed properties. Toward this goal, various 3,5-substituted parabens were synthesized and assessed for antimicrobial properties against <i>S. aureus</i> as well as competitive binding to the ER_α. The minimum inhibitory concentration assay confirmed retention of antimicrobial activity in many of these derivatives, while all compounds exhibited decreased xenoestrogen activity as determined by a combination of competitive enzyme linked immunosorbent assay (ELISA), proliferation, and estrogen receptor binding assay. Thus, these changes to the paraben scaffold have led to a multitude of paraben derivatives with antimicrobial properties up to 16 times more active than the parent paraben and that are devoid or significantly diminished of potential breast cancer causing properties

The lobster navigators

When experimentally displaced in geomagnetic space, spiny lobsters act as if to make their way home. This is a fascinating case of navigation by an invertebrate using a magnetic map sense