Flavonoids are important biomolecules with a variety of pharmaceutical and agricultural applications. Currently, isolating these compounds is done by plant extraction, however this process is hindered by large land and energy requirements. Previous groups have aimed to overcome these challenges by engineering microbes to produce these important compounds, however this is largely bottlenecked by the lack of intercellular malonyl-CoA availability. To remedy this, the genes matB and matC have been identified as coding for malonyl-CoA synthase and a putative dicarboxylate carrier protein, respectively. Other works have successfully engineered two variants, Streptomyces coelicolor and Rhizobium trifolii, of these genes into Escherichia coli, however this has yet to be accomplished in Gram-positive Corynebacterium glutamicum. Additionally, other groups have neglected to attempt tuning these genes with respect to one another by inserting in front of different inducible promoters. This study has successfully assembled two plasmids containing the Streptomyces coelicolor and Rhizobium trifolii variants of both matB and matC. Preliminary fermentations and GCMS results confirmed that little to none naringenin was produced without the matB-matC module. Additionally, preliminary fermentations revealed that the DelAro1 and DelAro3 strains can be used to reduce metabolism of aromatics like naringenin.

Ammonia is one of the most important chemicals for modern civilization as well as a potentially invaluable intermediary component of a future sustainable H2 economy, yet its current production is decidedly unsustainable. Accordingly, researchers are attempting to devise new paradigms for ammonia production, one of which would involve the cyclical reaction of H2 with a nitride compound and the renitridation of that compound with N2 - a thermochemical loop that would allow for ammonia production with renewable inputs and at relatively low pressures. In this paper, researchers identified several ternary and quaternary metal nitrides with the potential to exhibit relatively favorable thermodynamics for both the reduction and nitridation steps of that reaction cycle. These compounds were synthesized via co-precipitation and Pechini synthesis and several were tested under gas flows of 75% H2/Ar at 100-700 C and 75% H2/N2 at 700 C to determine their behavior under these conditions. As suggested by the available literature, Co3Mo3N was found to be a far better candidate for thermochemical looping than Fe3Mo3N or Ni2Mo3N - with higher mass loss and mass regain. Interestingly, quaternary nitrides containing Fe and Co in addition to Mo also demonstrated remarkable reduction and nitridation capability under ambient pressures. Ultimately, this paper demonstrates the feasibility of synthesizing a variety of single phase ternary and quaternary nitrides and the potential that several of these nitrides hold for producing ammonia sustainably via cyclic thermochemistry.

Esters are important solvents in multiple industries including adhesives, food, and pharmaceuticals. Although esters are biodegradable solvents, the conventional process of producing them is not eco-friendly because they are largely derived from petrochemicals. This has led scientists to consider implementing biological routes in their production process by incorporating heterologous or improving inherent esterification pathways. However, due to inequality in the biosynthesis of esters and their precursors (organic acid and alcohol), a significant amount of precursors are left unconverted, thereby lowering overall esterification efficiency. Therefore, the primary goal of the current research is to improve the ester titers by incorporating one more step of in vitro esterification with the culture broth, thereby esterifying the unconverted precursors using high efficiency commercial enzymes in the presence of compatible organic solvent. In principle, the medium containing the precursors will be treated with the enzyme in presence of organic solvent, where the precursors will be distributed in both the phases, aqueous and organic, based on their polarity, and the enzymatic esterification will happen at the interface. Hence, as a first step, efforts were made to optimize the reaction conditions, beginning with choosing the most efficient organic solvent and corresponding enzyme candidate. Our results showed that, for production of ethyl acetate through this reactive extraction approach, Novozyme435 exhibited significant esterification with chloroform, with almost 85% conversion efficiency. Further optimizations with phase ratios, pH and incubation time showed that the pH 6.0 (3.1 g/L) was the most optimum where ethyl acetate titer was found to improve 10 times than that at pH 7.0 (0.164 g/L) with the phase ratio of 1:1. The kinetic studies further added that the incubation at 37oC gives the maximum ethyl acetate production within 8h. After initial optimization studies, cell broth from E. coli cells transformed to overproduce an esterase was also tested with the reactive extraction method. It was found that there was a ~7.5X decrease in ethyl acetate production in the cell media versus synthetic samples with the same concentration of reactants. Such a large decrease indicates that enzymatic promiscuity or inhibition currently prevent the cell samples from reaching the same conversion as synthetic studies. To characterize the maximum reaction rate (Vmax) and affinity constants of the substrates to Novozym 435, further kinetic studies were performed with one minute of reaction. The mathematical model employed assumes that enzyme kinetics rather than diffusion was the rate limiting step, that the concentrations of reactants at the interface are equivalent to the initial concentration of reactants, and that neither substrate is an inhibitor. Vmax was found to be 18.5 Mmol min-1g-1 (of catalyst used), and the affinity constants were 0.957 M and 0.00557 M for acetic acid and ethanol respectively. Vmax was similar to literature values with Novozym 435, and the affinity constants indicate a much higher binding efficiency of ethanol in comparison to acetic acid, indicating that a cocktail of esters are likely produced from Novozym 435 in cell broth. Overall, moving away from fossil-fuel dependence is necessary to promote sustainable industry standards, and microbial cell factories combined with reactive extraction, if optimized for industrial applications, can replace harmful environmental procedures. By optimizing the reactive extraction process for ester production, biorefineries could become more competitive and economically feasible for numerous applications.

It is a fact of modern food processing that the majority of products contain one or multiple food additives. Yet, while these additives see great abundance of use, the average consumer has relatively little knowledge about them and, more often than not, a negative opinion of their inclusion. This piece explores the discrepancy between these two realities by delving into the origins, histories of use, health effects, and misconceptions that surround a number of modern food additives, exploring along the way the social changes and regulatory history that brought about the legal landscape of food safety in the United States. Ten author-developed recipes are included at the end to encourage not only a conceptual, but also a practical familiarity with these same food additives.

The main scope of this study was to analyze the impact support and identity have on the collegiate athletic career transition process. While student-athletes undergo a variety of transitions, this study focused on the career transition out of collegiate athletics regardless of their reason for leaving or their next steps. The motivation for conducting this research is to take the challenges and recommendations to the next steps and reform the common practice of career transition and provide assistance to athletes facing adversity in this position. A study on 32 voluntary student-athletes in different phases of the transition process ranging from current student-athletes to graduated student-athletes years detached from their sport was conducted via electronic questionnaire. Questions about demographics and their personal experiences relating to identity, support, and transition as a whole were asked regarding their time as student-athletes through their transition (if applicable). Through analyzing the responses and previous literature, it is evident that support is necessary from the early stages as a student-athlete through their transition out of the sport to minimize the negative impact. It is also apparent that one's athletic identity is established early on in their career and is difficult to dissociate from to rediscover a personal identity not connected to athletic performance. Knowing what we do now, there are limitations in the findings such as within the demographics, questionnaire, and clarity. This would be beneficial to research and study further to optimize a solution to assist in the athletic career transition process and alleviate additional barriers athletes face when no longer having their sport.