Anaerobic digestion of feedlot cattle manure and specified risk materials: energy production and prion degradation

Bibliography: p. 140-16

Impact of manure storage conditions and time on decomposition and losses from liquid dairy manure stored in a temperate climate

Large volumes of generated animal manures necessitate knowledge of how its production and storage affects composition, losses, and utilization potential. Stratification of liquid dairy manure was the main source of observed variability within outdoor uncovered manure storage, during a yearlong monitoring of 24 different physicochemical manure parameters. Coefficient of variation (CV) ranged from 4-24% for plant nutrients to 33-89% for biogas feedstock parameters. N volatilization losses during storage between manure additions were ~10% moThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Comparing the Biomass Yield and Biogas Potential of Phragmites australis with Miscanthus x giganteus and Panicum virgatum Grown in Canada

The production of bioenergy from plant biomass has the potential to reduce fossil fuel use. The number of biogas facilities around the world has risen dramatically, increasing demand for feedstocks. In this study the invasive perennial grass Phragmites australis was evaluated as a biogas feedstock in comparison with Miscanthus x giganteus and Panicum virgatum. Results from three field sites for each species demonstrated that biomass yields for P. australis averaged approximately 1.82 ± 0.9 kg dry matter (DM) m−2, comparable to that of M. x giganteus. Yield of P. australis was greater than P. virgatum, which ranged from 0.49 ± 0.06 to 0.69 ± 0.07 kg DM m−2 in July and October, respectively. In mesophilic bench-top digester experiments, methane yields were greater for July-harvested material than for October, ranging from 172.4 ± 15.3 to 229.8 ± 15.2 L CH4 kg−1 volatile solids (VS) for all perennial grasses. Methane yields per hectare were highest for October-harvested M. x giganteus, followed by July-harvested M. x giganteus and P. australis, whereas methane yield from P. virgatum at both harvest times was lower than the other two species. These results suggest that P. australis is not an economically viable biogas feedstock without pre-treatment to improve methane yield

Evaluation and modelling of methane production from corn stover pretreated with various physicochemical techniques

8 Páginas.-- 3 Tablas.-- 2 FigurasLignocellulosic by-products from agricultural crops represent an important raw material for anaerobic digestion and clean renewable, which is a key component of the circular economy. Lignocellulose is recalcitrant to biodegradation and pretreatments are required to increase methane yield during anaerobic digestion. In this work, the efficacy of different physicochemical pretreatments was compared using corn stover biomass as substrate. Anaerobic digestion of untreated and pretreated corn stover was performed in batch mode at mesophilic temperature (38°C) and organic matter solubilization of pretreated substrates was also investigated. The highest organic matter solubilization occurred in autoclave pretreatment (soluble chemical oxygen demand = 5630 ± 42 mg O2 L-1). However, the highest methane yield was obtained using alkaline pretreatment (367 ± 35 mL CH4 g-1 VSadded). Alkaline pretreatment increased methane yield by 43.3% compared to untreated control (256 ± 15 mL CH4 g-1 VSadded). Two mathematical models (i.e. first-order kinetics and transfer function) were utilized to fit the experimental data with the aim of assessing anaerobic biodegradation and to obtain the kinetic constants in all cases studied. Both models adequately fit the experimental results. The kinetic constant, k, of the first-order model increased by 92.8% when stover was pretreated with sulphuric acid compared with control. The transfer function model revealed that the maximum methane production rate, Rm, was obtained for the sulphuric acid treatment, which was 63.5% higher compared to control.The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Natural Sciences and Engineering Research Council of Canada (grant number 400806); the Ontario Ministry of Agriculture Food and Rural Affairs (grant number UofG2015-2327); and Junta de Andalucía, Consejería de Economía y Conocimiento (Project of Excellence RNM-1970).Peer reviewe

Protein can be taken up by damaged wheat roots and transported to the stem

Proteins of animal origin can represent a portion of the overall nitrogen (N) pool in the soil environment and there is a possibility that plants may utilize animal proteins as a N source. Using wheat (Triticum aestivum L.) we investigated if the model protein, ovalbumin was taken up into the roots and transported within the plant. In roots, ovalbumin was associated with the epidermis when no root damage was evident, but with minor root damage, it was present in intercellular spaces throughout the cortex and at the endodermis. Ovalbumin was only found in the stem when minor damage to the root system was evident. Suspension cultures of wheat protoplasts revealed that ovalbumin was not assimilated into individual plant cells. Our results suggest that ovalbumin uptake and subsequent movement in wheat is possible only after root damage has occurred. Apoplastic movement may enable animal protein to enter plant tissues above the soil level where they could be consumed by grazers

Efficiency of protein as a nitrogen source for wheat and morphological changes in roots exposed to high protein concentrations

Proteins of animal origin can enter the environment through application of agricultural by-products to arable or pastured land. In this study, wheat (Triticum aestivum cv. AC Andrew) was exposed to treatments with nitrogen (N) supplied as animal protein (bovine serum albumin; BSA), inorganic N or a combination of these sources at different iso-nitrogenous concentrations. Plant growth was assessed by monitoring both wet and dry mass of shoots and data showed that protein treatments did not differ (P > 0.05) from controls lacking N. Analysis of N also showed that plants supplied with protein N displayed lower N (1.2-2.4%) concentration as compared with those supplied with inorganic N (up to 12.4%) with N remaining 71 mM, with the development of knob-like outgrowths with unknown function or significance. This study provides evidence that wheat plantlets grown under sterile conditions are unable to utilize BSA as efficiently as NH4NO3 as a N source, but their roots exhibit a morphological response to protein

Can plants serve as a vector for prions causing chronic wasting disease?

Prions, the causative agent of chronic wasting disease (CWD) enter the environment through shedding of bodily fluids and carcass decay, posing a disease risk as a result of their environmental persistence. Plants have the ability to take up large organic particles, including whole proteins, and microbes. This study used wheat (Triticum aestivum L.) to investigate the uptake of infectious CWD prions into roots and their transport into aerial tissues. The roots of intact wheat plants were exposed to infectious prions (PrPTSE) for 24 h in three replicate studies with PrPTSE in protein extracts being detected by western blot, IDEXX and Bio-Rad diagnostic tests. Recombinant prion protein (PrPC) bound to roots, but was not detected in the stem or leaves. Protease-digested CWD prions (PrPTSE) in elk brain homogenate interacted with root tissue, but were not detected in the stem. This suggests wheat was unable to transport sufficient PrPTSE from the roots to the stem to be detectable by the methods employed. Undigested PrPTSE did not associate with roots. The present study suggests that if prions are transported from the roots to the stems it is at levels that are below those that are detectable by western blot, IDEXX or Bio-Rad diagnostic kits