Browsing by Author "Ebikade, Elvis Osamudiamhen"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item The impact of differential lignin S/G ratios on mutagenicity and chicken embryonic toxicity(Journal of Applied Toxicology, 2021-08-27) Zhang, Xinwen; Levia, Delphis F.; Ebikade, Elvis Osamudiamhen; Chang, Jeffrey; Vlachos, Dionisios G.; Wu, ChangqingLignin and lignin-based materials have received considerable attention in various fields due to their promise as sustainable feedstocks. Guaiacol (G) and syringol (S) are two primary monolignols that occur in different ratios for different plant species. As methoxyphenols, G and S have been targeted as atmospheric pollutants and their acute toxicity examined. However, there is a rare understanding of the toxicological properties on other endpoints and mixture effects of these monolignols. To fill this knowledge gap, our study investigated the impact of different S/G ratios (0.5, 1, and 2) and three lignin depolymerization samples from poplar, pine, and miscanthus species on mutagenicity and developmental toxicity. A multitiered method consisted of in silico simulation, in vitro Ames test, and in vivo chicken embryonic assay was employed. In the Ames test, syringol showed a sign of mutagenicity, whereas guaiacol did not, which agreed with the T.E.S.T. simulation. For three S and G mixture and lignin monomers, mutagenic activity was related to the proportion of syringol. In addition, both S and G showed developmental toxicity in the chicken embryonic assay and T.E.S.T. simulation, and guaiacol had a severe effect on lipid peroxidation. A similar trend and comparable developmental toxicity levels were detected for S and G mixtures and the three lignin depolymerized monomers. This study provides data and insights on the differential toxicity of varying S/G ratios for some important building blocks for bio-based materials.Item Kinetic studies of acid hydrolysis of food waste-derived saccharides(University of Delaware, 2019) Ebikade, Elvis OsamudiamhenStarch saccharified glucose from food waste can be an important precursor for renewable chemicals and fuels. Despite numerous studies on hydrolysis of biomass, detailed kinetic studies and associated models of hydrolysis are lacking. We investigated the kinetics of glycosidic bond scission of malto-oligosaccharides in lithium bromide acidified molten salt hydrate (AMSH) medium and estimated rate parameters from experimental data. Our data supports the hypothesis that the terminal, non-reducing bonds hydrolyze faster than the interior and terminal-reducing C-O bonds. Next, we extended the model to simulate the hydrolysis of linear and cyclic saccharides of varying degree of polymerization and of potato starch. We characterize starch using x-ray diffraction (XRD) and light scattering methods. The model is in excellent agreement with the experimentally determined concentrations of glucose and other oligosaccharides. The chain length of saccharides is found to be directly related to their hydrolysis rate constant, but inversely proportional to the glucose formation rate constant.Item A review of thermal and thermocatalytic valorization of food waste(Green Chemistry, 2021-04-08) Ebikade, Elvis Osamudiamhen; Sadula, Sunitha; Gupta, Yagya; Vlachos, Dionisios G.Food waste (FW) remains a global challenge due to the increasing demand for food production to support a growing global population and the lack of effective waste management technologies for recycling and upcycling. Unique compounds in FW – such as carbohydrates, proteins, lignin, fats, and extractives – can be repurposed to produce important biobased fuels, bulk chemicals, dietary supplements, adsorbents, and antibacterial products, among many others. We review the thermal and thermocatalytic FW valorization strategies and the fundamental pathways. We discuss the potential integration of various valorization processes, their economic viability, the technical and marketing challenges, and the need for further developments. By overcoming several technical hurdles, repurposing FW into modular plants can create exciting economic and environmental prospects.