Chemical-free recovery of crude protein from livestock manure digestate solid by thermal hydrolysis
Open Access
- 12 July 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Bioresources and Bioprocessing
- Vol. 8 (1), 1-12
- https://doi.org/10.1186/s40643-021-00406-1
Abstract
Protein is becoming an increasingly important resource for a variety of commercial applications. Yet, a large volume of protein is being wasted. Notably, livestock manure solids have a significant content of protein which is not only underutilized, but prone to runoff and eventual breakdown to reactive nitrogen compounds, contributing to eutrophication. It would be desirable to remove protein before it causes environmental hazards and then convert it to value-added commercial applications. We have developed a novel thermal hydrolysis process (THP) to extract crude protein from livestock manure solid, or manure digestate solid (MDS) in particular, without the use of any chemical. We demonstrate the versatility of our new process to control the molecular weight (MW) distribution of the extracted protein hydrolysate (PH). The antioxidant activity of the crude protein hydrolysate (CPH) has been examined through Oxygen Radical Absorbance Capacity Assay. The results have shown that our CPH had its antioxidant capacity against the peroxyl radical similar to that of vitamin E and exhibited almost 7 times as strong inhibition against the hydroxyl radical as vitamin E. We also evaluated the nutritional value of our PH by analyzing its amino acid composition and the MW distribution through amino acid analysis, SDS-PAGE, and MALDI-TOF mass spectroscopy. The characterizations have revealed that the PH recovered from MDS had 2.5 times as much essential amino acids as soybean meal on dry matter basis, with the MW distribution ranging from over a 100 Da to 100 KDa. Finally, the protein powder was prepared from the extracted CPH solution and its composition was analyzed.This publication has 51 references indexed in Scilit:
- Assessment of the influence of thermal pre-treatment time on the macromolecular composition and anaerobic biodegradability of sewage sludgeBioresource Technology, 2011
- Asymptomatic deer excrete infectious prions in faecesNature, 2009
- Protective effect of an antioxidative peptide purified from gastrointestinal digests of oyster, Crassostrea gigas against free radical induced DNA damageBioresource Technology, 2008
- Proteolysis of ProPTHrP(1–141) by “Prohormone Thiol Protease” at Multibasic Residues Generates PTHrP-Related Peptides: Implications for PTHrP Peptide Production in Lung Cancer CellsBiochemical and Biophysical Research Communications, 2001
- Nonbiodegradable Organic Compounds Found in Automotive Spraybooth Scrubber WaterWater Environment Research, 2000
- Kinetic Role of Electrostatic Interactions in the Unfolding of Hyperthermophilic and Mesophilic RubredoxinsBiochemistry, 1998
- Disruption of an ionic network leads to accelerated thermal denaturation of d-glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic bacterium Thermotoga maritimaJournal of Molecular Biology, 1997
- Ferredoxin from the hyperthermophile Thermotoga maritima is stable beyond the boiling point of waterJournal of Molecular Biology, 1997
- Equilibrium DNA Binding of Sac7d Protein from the HyperthermophileSulfolobus acidocaldarius: Fluorescence and Circular Dichroism Studies,Biochemistry, 1996
- The thermal decomposition of biureaJournal of the Chemical Society, Perkin Transactions 2, 1978