PARAFAC Modeling of Irradiation- and Oxidation-Induced Changes in Fluorescent Dissolved Organic Matter Extracted from Poultry Litter

Abstract

Parallel factor analysis (PARAFAC) applied to fluorescence excitation emission matrices (EEMs) allows quantitative assessment of the composition of fluorescent dissolved organic matter (DOM). In this study, we fit a four-component EEM-PARAFAC model to characterize DOM extracted from poultry litter. The data set included fluorescence EEMs from 291 untreated, irradiated (253.7 nm, 310-410 nm), and oxidized (UV-HO, ozone) poultry litter extracts. The four components were identified as microbial humic-, terrestrial humic-, tyrosine-, and tryptophan-like fluorescent signatures. The Tucker's congruence coefficients for components from the global (i.e., aggregated sample set) model and local (i.e., single poultry litter source) models were greater than 0.99, suggesting that the global EEM-PARAFAC model may be suitable to study poultry litter DOM from individual sources. In general, the transformation trends of the four fluorescence components were comparable for all poultry litter sources tested. For irradiation at 253.7 nm, ozonation, and UV-HO advanced oxidation, transformation of the humic-like components was slower than that of the tryptophan-like component. The opposite trend was observed for irradiation at 310-410 nm, due to differences in UV absorbance properties of components. Compared to the other EEM-PARAFAC components, the tyrosine-like component was fairly recalcitrant in irradiation and oxidation processes. This novel application of EEM-PARAFAC modeling provides insight into the composition and fate of agricultural DOM in natural and engineered systems.

Study on Dissolution Characteristics of Excess Sludge by Low-Temperature Thermal Hydrolysis and Acid Production by Fermentation

“… 39 Cellulose and other refractory organics are not degraded during anaerobic fermentation. 40 Valeric acid underwent a process of decreasing first and then increasing during the fermentation process, indicating that the thermal treatment process promoted the conversion of biological macromolecules to small molecules, which was beneficial to fermentation and acid production. From the point of view of fermentation time, all fermentation acid-producing sludges can reach the peak of acid production within 3 days, and after the fourth day, they rapidly decrease and maintain a low concentration, indicating that the organic substances that are easily used by the organism are basically consumed and the refractory substances are slowly hydrolyzed and fermented.…”

New insights into the variation of dissolved organic matter components in different latitudinal lakes of northeast China

“…The Tucker's congruence coefficient of all components was > 0.99, indicating that EEM‐PARAFAC model can be applied to analyze DOM changes resulting from latitude‐driven for all water sample sites. The F max % values were used to compare fluorescence of a single component across different latitudes samples (Ohno et al ; Mangalgiri et al ). Meanwhile, the concentration of all DOM samples was diluted to a same level at 10 mg C L −1 to make the comparison valid.…”

Fluorescence regional integration combined with parallel factor analysis to quantify fluorescencent spectra for dissolved organic matter released from manure biochars

“…The excitation ranges were restricted to 250-500 nm to avoid the deteriorating signal/noise ratio in the low excitation wavelength region for PARAFAC analysis. 29,30 Four uorescent components (C1-C4) were identied by PARAFAC modelling, and the EEM contours of each individual component were illustrated in Fig. 5.…”

“…5. As reported in the literature, the C1 component (l Ex/ l Em ¼ 310/404 nm) was categorized as UVA marine humic-like, 14,31 and terrestrial humic-like (665-1000 Da), 13 microbial humic-like, 29 and humic-like highly processed terrigenous. 32 The C2 component (l Ex /l Em ¼ 350/436 nm) was assigned a microbial reduced quinone-like component, 14 UVA humic acid-like, 12,33 and humic-like less processed terrigenous.…”