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1. Influence of methylation on the effectiveness of meat and bone meal protein as a bioflocculant

Author:
Garcia, Rafael A.,   et al.   ; Essandoh, Matthew; Nieman, Christine M.; Strahan, Gary D.;     Show all 4 Authors
Source:
Food and bioproducts processing 2020 v.122 pp. 55-61
ISSN:
0960-3085
Subject:
acid hydrolysis; carboxylic acids; colloids; flocculants; gel chromatography; hydrolysates; meat and bone meal; methylation; nuclear magnetic resonance spectroscopy; pH; protein hydrolysates
Abstract:
... In this study, the enhancement in the application of meat and bone meal (MBM) protein as a bioflocculant was studied through methylation and dilute acid hydrolysis. Nuclear magnetic resonance (HSQC and CIGAR-HMBC) revealed that MBM proteins are being effectively methylated at their carboxylic acid groups. Size exclusion chromatography (SEC) coupled with tetra-detection system was used to obtain in ...
DOI:
10.1016/j.fbp.2020.03.009

2. Performance and mechanism of polypeptidylated hemoglobin (Hb)/iron oxide magnetic composites for enhanced dye removal

Author:
Garcia, Rafael A.,   et al.   ; Essandoh, Matthew; Gayle, Makahra R.; Nieman, Christine M.;     Show all 4 Authors
Source:
Chemosphere 2020 v.247 pp. 125897
ISSN:
0045-6535
Subject:
adsorbents; adsorption; coprecipitation; dyes; hemoglobin; iron oxides; magnetism; methanol; pH; polymerization; surface area; temperature
Abstract:
... Composites of polypeptidylated hemoglobin supported on different iron oxide weights (0.5:1 and 1:1) were developed and demonstrated to function as efficient adsorbents for Eriochrome black-T dye removal. The synthesis of these adsorbents were performed through N-carboxyanhydride (NCA) polymerization at low temperature (4 °C) and near-neutral pH for 24 h followed by chemical co-precipitation. The s ...
DOI:
10.1016/j.chemosphere.2020.125897

3. Efficient removal of dyes from aqueous solutions using a novel hemoglobin/iron oxide composite

Author:
Garcia, Rafael A.,   et al.   ; Essandoh, Matthew;     Show all 2 Author
Source:
Chemosphere 2018 v.206 pp. 502-512
ISSN:
0045-6535
Subject:
Fourier transform infrared spectroscopy; adsorption; aqueous solutions; electrostatic interactions; erythrosine; hemoglobin; indigo carmine; iron oxides; isoelectric point; kinetics; magnetic materials; magnetism; particle size; scanning electron microscopy; sorption isotherms; tartrazine; thermal stability; thermogravimetry; toxicity
Abstract:
... Magnetic particles entrapped in different matrices that display high thermal stability, low toxicity, interactive functions at the surface, and high saturation magnetization are of great interest. The objective of this work was to synthesize a novel hemoglobin/iron oxide composite (Hb/Fe₃O₄) for the removal of different dyes (indigo carmine, naphthol blue black, tartrazine, erythrosine, eriochrome ...
DOI:
10.1016/j.chemosphere.2018.04.182

4. Do people care about pine invasions? Visitor perceptions and willingness to pay for pine control in a protected area

Author:
García, Rafael A.,   et al.   ; Bravo-Vargas, Valentina; Pizarro, J. Cristóbal; Pauchard, Aníbal;     Show all 4 Authors
Source:
Journal of environmental management 2019 v.229 pp. 57-66
ISSN:
0301-4797
Subject:
Araucaria araucana; Pinus; aesthetics; attitudes and opinions; biodiversity; coniferous forests; conifers; conservation areas; ecosystem services; ecosystems; education; environmental impact; ethics; funding; invasive species; landscapes; questionnaires; snow; social benefit; summer; surveys; willingness to pay; winter; South America
Abstract:
... Tree invasions are increasing globally, causing major problems for biodiversity, ecosystem services and human well-being. In South America, conifer invasions occur across many ecosystems and while numerous studies address the ecological consequences of these invasions, little is known about social perceptions and people's attitudes toward their control. The social perceptions on the effect of inva ...
DOI:
10.1016/j.jenvman.2018.07.018

5. Chemical and Enzymatic Protein Cross-Linking To Improve Flocculant Properties

Author:
Garcia, Rafael A.,   et al.   ; Essandoh, Matthew; Nieman, Christine M.;     Show all 3 Authors
Source:
ACS sustainable chemistry & engineering 2018 v.6 no.10 pp. 12946-12952
ISSN:
2168-0485
Subject:
bovine serum albumin; crosslinking; flocculants; flocculation; hemoglobin; isoelectric point; molecular weight
Abstract:
... Some proteins promote the flocculation of aqueous suspensions, but proteins are much smaller than modern polymeric flocculants, and they are often not as potent. In this study, two globular proteins, hemoglobin (Hb) and bovine serum albumin (BSA), were cross-linked through either chemical or enzymatic means. The degree of cross-linking was approximately 95%. Compared to the native proteins, the cr ...
DOI:
10.1021/acssuschemeng.8b02395

6. Effect of long term cold storage and microwave extraction time on the physical and chemical properties of citrus pectin

Author:
Garcia, Rafael A.,   et al.   ; Fishman, Marshall L.; Chau, Hoa K.; Hotchkiss, Arland T.; White, Andre; Cooke, Peter H.;     Show all 6 Authors
Source:
Food hydrocolloids 2019 v.92 pp. 104-116
ISSN:
0268-005X
Subject:
Citrus; arabinogalactans; asparagine; aspartic acid; atomic force microscopy; cold; cold storage; esterification; galacturonic acid; gel chromatography; glutamic acid; hydrocolloids; leucine; lysine; molecular weight; phenylalanine; polygalacturonic acid; sugar content; tyrosine; viscosity
Abstract:
... Pectin, acid-extracted by microwave heating under pressure from orange and lime albedo, was cold (−20 °C) stored for 14 years and the physical and chemical properties were compared to the properties of the original microwave-extracted pectin prior to cold storage. The pectin physical and chemical properties were measured by using multi-detector high performance size exclusion chromatography (HPSEC ...
Handle:
10113/6295581
DOI:
10.1016/j.foodhyd.2018.12.047

7. The relationship between extent of hemoglobin purification and the performance characteristics of a blood‐based flocculant

Author:
Garcia, Rafael A,   et al.   ; Bumanlag, Lorelie P; Piazza, George J;     Show all 3 Authors
Source:
Journal of the science of food and agriculture 2017 v.97 no.14 pp. 4822-4826
ISSN:
0022-5142
Subject:
blood; chemical oxygen demand; flocculants; flocculation; hemoglobin; kaolin; nitrogen; pH; pollutants
Abstract:
... BACKGROUND: Whole blood is a highly complex substance. Hemoglobin, the most abundant blood protein, can function as a flocculant; most of the other blood components exhibit poor flocculant activity. For the purpose of processing raw whole blood into a flocculant product, the practical value of hemoglobin purification is uncertain. RESULTS: This study compares the flocculant performance of whole bl ...
DOI:
10.1002/jsfa.8352

8. Methylation of hemoglobin to enhance flocculant performance

Author:
Garcia, Rafael A,   et al.   ; Essandoh, Matthew; Strahan, Gary D;     Show all 3 Authors
Source:
Journal of chemical technology and biotechnology 2017 v.92 no.8 pp. 2032-2037
ISSN:
0268-2575
Subject:
flocculants; flocculation; hemoglobin; hydrochloric acid; kaolin; lignin; methanol; methylation; moieties; pH; titration; turbidity
Abstract:
... BACKGROUND: Synthetic organic polymer flocculants can be highly effective at clarifying suspensions, but these substances may also have negative environmental and health effects. Relatively few studies have been done using biobased flocculants, which are more environment friendly. Hemoglobin (Hb) has previously been demonstrated to be a promising flocculant of kaolin and lignin suspensions. This s ...
DOI:
10.1002/jctb.5197

9. Flocculation of wheat straw soda lignin by hemoglobin and chicken blood: effects of cationic polymer or calcium chloride

Author:
Garcia, Rafael A,   et al.   ; Piazza, George J; Lora, Jairo H;     Show all 3 Authors
Source:
Journal of chemical technology and biotechnology 2017 v.92 no.4 pp. 793-800
ISSN:
0268-2575
Subject:
biomass; blood; byproducts; calcium chloride; cations; chemical oxygen demand; chickens; feeds; flocculants; flocculation; hemoglobin; lignin; neutralization; solubility; wheat straw; zeta potential
Abstract:
... BACKGROUND: Lignin is the largest byproduct of biomass processing. Flocculation could replace strong acid used in lignin recovery and be useful for the cleanup of lignin from residual processing waters. Commercial nonrenewable flocculants are known to be effective with lignin, but the investigation of renewable lignin flocculants has received little attention. RESULTS: Methods were developed to ec ...

10. Solubilization of meat & bone meal protein by dilute acid hydrolysis for the production of bio-based flocculant

Author:
Garcia, Rafael A.,   et al.   ; Zhang, Congmu; Piazza, George J.;     Show all 3 Authors
Source:
Food and bioproducts processing 2017 v.102 pp. 362-366
ISSN:
0960-3085
Subject:
acid hydrolysis; asparagine; aspartic acid; bone meal; enzymatic hydrolysis; erosion control; flocculants; flocculation; gel chromatography; hydrochloric acid; kaolin; meat; meat and bone meal; meat processing; molecular weight; nitrogen; papermaking; solubility; solubilization; solutes; wastewater treatment
Abstract:
... Flocculants are substances that cause suspended particles to aggregate, therefore accelerating sedimentation to produce a clarified solution. They find use in a huge variety of applications including wastewater treatment, erosion control, and paper manufacture. Meat and bone meal (MBM) is a high protein by-product of meat processing. Protein extracted from MBM has been shown to have good flocculat ...
DOI:
10.1016/j.fbp.2017.02.004

11. Application of the Elusieve Process to the Classification of Meat and Bone Meal Particles

Author:
Garcia, Rafael A.,   et al.   ; Piazza, George J.;     Show all 2 Author
Source:
Applied engineering in agriculture 2015 v.31 no.1 pp. 165-170
ISSN:
0883-8542
Subject:
air; air flow; ash content; distillers grains; industry; meat and bone meal; particles; rendering; screening; streams
Abstract:
... Meat and bone meal (MBM), a product of the rendering industry, comprises a mixture of two particle types. The utility and value of MBM would increase if the two particle types could be separated economically. Past efforts at classification of MBM particles have achieved limited success. In the present research, a classification method originally developed for distillers dried grains is applied wit ...
DOI:
10.13031/aea.31.10410

12. Application of the Elusieve Process to the Classification of Meat and Bone Meal Particles

Author:
Garcia, Rafael A.,   et al.   ; Piazza, George J.;     Show all 2 Author
Source:
Applied engineering in agriculture 2015 v.31 no.1 pp. 165-170
ISSN:
0883-8542
Subject:
particles; classification; rendering; industry; streams; ash content; air; meat and bone meal; distillers grains; air flow; screening; separation
Abstract:
... Meat and bone meal (MBM), a product of the rendering industry, comprises a mixture of two particle types. The utility and value of MBM would increase if the two particle types could be separated economically. Past efforts at classification of MBM particles have achieved limited success. In the present research, a classification method originally developed for distillers dried grains is applied wit ...
Handle:
10113/60634
DOI:
10.13031/aea.31.10410

13. Practical Limitations of the Dilute Acid Hydrolysis Method for Solubilizing Meat and Bone Meal Protein

Author:
Garcia, Rafael A.,   et al.   ; Essandoh, Matthew; Nieman, Christine M.; Bumanlag, Lorelie P.; Piazza, George J.; Zhang, Congmu;     Show all 6 Authors
Source:
ACS sustainable chemistry 2017 v.5 no.12 pp. 11652-11659
ISSN:
2168-0485
Subject:
acid hydrolysis; flocculants; green chemistry; meat and bone meal; particle size; peptides; protein hydrolysates; solubilization
Abstract:
... A previous study reported conditions that hydrolyze meat and bone meal (MBM) protein in a site-specific manner, transforming insoluble MBM protein into large, soluble protein fragments with good flocculant functionality. It is not clear, however, that this phenomenon can be adapted for industrial-scale processing of MBM at reasonable expense. The present study examines whether the desirable charac ...
DOI:
10.1021/acssuschemeng.7b03050

14. Removal of lignin from straw spent pulping liquor using synthetic cationic and biobased flocculants

Author:
Garcia, Rafael A.,   et al.   ; Piazza, George J.; Lora, Jairo H.; Wayman, Luke I.;     Show all 4 Authors
Source:
Separation and Purification Technology 2017 v.188 pp. 348-357
ISSN:
1383-5866
Subject:
absorption; alkaline pulping; calcium chloride; centrifugation; flocculants; flocculation; hemoglobin; lignin; spectroscopy; straw; turbidity; zeta potential
Abstract:
... The spent pulping liquor (SPL) obtained from straw processed by soda (alkaline) pulping contains dissolved non-sulfonated lignin. The lignin can be separated from SPL using acid or cationic flocculants which are potentially hazardous to the environment. In this study, the performance of the biobased protein flocculant hemoglobin (HEM) with and without added calcium chloride was compared with that ...
Handle:
10113/5801860
DOI:
10.1016/j.seppur.2017.07.042

15. Pine invasion impacts on plant diversity in Patagonia: invader size and invaded habitat matter

Author:
García, Rafael A.,   et al.   ; Franzese, Jorgelina; Urrutia, Jonathan; Taylor, Kimberley; Pauchard, Aníbal;     Show all 5 Authors
Source:
Biological invasions 2017 v.19 no.3 pp. 1015-1027
ISSN:
1387-3547
Subject:
Araucaria; Pinus contorta; canopy; conifers; crops; ecosystems; forests; habitats; plant communities; planting; species diversity; steppes; trees; Argentina; Chile
Abstract:
... Conifers, which are widely planted as fast growing tree crops, are invading forested and treeless environments across the globe, causing important changes in biodiversity. However, how small-scale impacts on plant diversity differ according to pine size and habitat context remains unclear. We assessed the effects of different stages of pine invasion on plant communities in forest and steppe sites ...
DOI:
10.1007/s10530-016-1344-6

16. French broom (Teline monspessulana) invasion in south-central Chile depends on factors operating at different spatial scales

Author:
García, Rafael A.,   et al.   ; Pauchard, Aníbal; Escudero, Adrián;     Show all 3 Authors
Source:
Biological invasions 2014 v.16 no.1 pp. 113-124
ISSN:
1387-3547
Subject:
Fabaceae; canopy; climate; ecological invasion; environmental factors; forest plantations; invasive species; land use; rain; roads; shrubs; trees; urban areas; Chile
Abstract:
... The interaction between plant attributes, environmental factors and the history of human intervention determines which species show a more invasive behavior and which areas are more likely to be invaded. Identifying which factors favor the invasion and which constraint it, remains an essential goal for understanding the process of invasion and to provide a stronger scientific basis for designing m ...
DOI:
10.1007/s10530-013-0507-y

17. Flocculation of kaolin and lignin by bovine blood and hemoglobin

Author:
Garcia, Rafael A.,   et al.   ; Piazza, George J.; Lora, Jairo H.;     Show all 3 Authors
Source:
Journal of chemical technology and biotechnology 2015 v.90 no.8 pp. 1419-1425
ISSN:
0268-2575
Subject:
anions; biotechnology; blood; cations; cattle; chemical concentration; erosion control; flocculants; flocculation; hemoglobin; irrigation canals; kaolin; lignin; pH; polyacrylamide; quaternary ammonium compounds; sodium chloride; soil erosion; water purification
Abstract:
... BACKGROUND: The kaolin flocculant activities of bovine blood (BB) and hemoglobin (HEM) at different salt and pH values were determined. Lower limit concentration (LLC), window of application (WA), and degrees of clarification (DC) values for BB and HEM were determined and compared with those of the synthetic polymeric flocculants poly(diallydimethylammonium chloride) (PDADMAC), cationic polyacryla ...
DOI:
10.1002/jctb.4443

18. Ultrasonic processing for recovery of chicken erythrocyte hemoglobin

Author:
Garcia, Rafael A.,   et al.   ; Clevenstine, Shaina M.; Piazza, George J.;     Show all 3 Authors
Source:
Food and bioproducts processing 2015 v.94 pp. 1
ISSN:
0960-3085
Subject:
acoustics; calorimetry; chickens; clay; electric power; energy conversion; erythrocytes; flocculants; flocculation; hemoglobin; kaolin; probes (equipment); ultrasonic equipment; ultrasonic treatment
Abstract:
... Hemoglobin from chicken blood has been shown to be a good substitute for synthetic polymeric flocculants. One stage of processing the blood entails lysis of the cells to release the hemoglobin; in the present study, the use of ultrasonic processing at this stage is investigated. Washed chicken blood cells are suspended in buffer and run continuously through a chamber attached to an ultrasonic prob ...
Handle:
10113/60217
DOI:
10.1016/j.fbp.2014.12.002

19. Properties of starch–polyglutamic acid (PGA) graft copolymer prepared by microwave irradiation − Fourier transform infrared spectroscopy (FTIR) and rheology studies

Author:
Garcia, Rafael A.,   et al.   ; Xu, Jingyuan; Solaiman, Daniel; Ashby, Richard D.; Gordon, Sherald H.; Harry‐O'kuru, Rogers E.;     Show all 6 Authors
Source:
Die Stärke = 2017 v.69 no.3-4
ISSN:
0038-9056
Subject:
Fourier transform infrared spectroscopy; agricultural products; composite polymers; crosslinking; equations; gels; microwave radiation; rheology; stress relaxation; viscoelasticity
Abstract:
... The rheological properties of waxy starch‐γ‐polygutamic acid (PGA) graft copolymers were investigated. Grafting was confirmed by FTIR spectroscopy. The starch–PGA copolymers absorbed water and formed gels, which exhibited concentration‐dependent viscoelastic solid properties. Higher starch–PGA concentrations resulted in stronger viscoelastic properties. The analysis for moduli of different concent ...
Handle:
10113/5715072
DOI:
10.1002/star.201600021
CHORUS:
10.1002/star.201600021

20. Preparation of starch–poly–glutamic acid graft copolymers by microwave irradiation and the characterization of their properties

Author:
Garcia, Rafael A.,   et al.   ; Xu, Jingyuan; Krietemeyer, Elizabeth F.; Finkenstadt, Victoria L.; Solaiman, Daniel; Ashby, Richard D.;     Show all 6 Authors
Source:
Carbohydrate polymers 2016 v.140 pp. 233-237
ISSN:
0144-8617
Subject:
aqueous solutions; composite polymers; corn starch; gels; microwave radiation; nitrogen; pH; polyglutamic acid; rheology; starch; temperature; viscoelasticity; waxy corn
Abstract:
... Graft copolymers of waxy maize starch and poly-γ-glutamic acid (PGA) were produced in an aqueous solution using microwave irradiation. The microwave reaction conditions were optimized with regard to temperature and pH. The temperature of 180°C and pH7.0 were the best reaction conditions resulting in a PGA graft of 0.45% based on nitrogen analysis. The average graft content and graft efficiency for ...
Handle:
10113/5244604
DOI:
10.1016/j.carbpol.2015.12.034
Chorus Open Access:
10.1016/j.carbpol.2015.12.034