What we talk about when we talk about protein hydrolyzate-based biostimulants

Luciano Cavani; Alja Margon; Luigi Sciubba; Claudio Ciavatta; Claudio Marzadori; Luciano Cavani; Alja Margon; Luigi Sciubba; Claudio Ciavatta; Claudio Marzadori

doi:10.3934/agrfood.2017.3.221

AIMS Agriculture and Food

2017, Volume 2, Issue 3: 221-232. doi: 10.3934/agrfood.2017.3.221

Previous Article Next Article

Research article Special Issues

What we talk about when we talk about protein hydrolyzate-based biostimulants

Department of Agricultural Sciences, Alma Mater Studiorum University of Bologna, I-40127 Bologna, Italy

Received: 05 June 2017 Accepted: 13 July 2017 Published: 17 July 2017

Protein hydrolyzates (PHs) are a well-known group of plant biostimulants that are obtained by thermal, chemical, enzymatic or mixed hydrolysis from animal or plant sources. PHs are mainly applied to plants with the aim to improve their nutrition level, stimulate metabolism, and increase resistance to abiotic stress. Chemically, the PHs are a mixture of free amino acids, oligo- and polypeptides. Considering the differences in the source materials and hydrolytic processes used for their production it is not surprising that PHs are a very complex and inhomogeneous category of biostimulants. This is a critical point that should be considered by both manufacturers and potential users of such products. With the aim to identify a putative correlation among PHs physic-chemical properties, the different source materials and the hydrolytic process used for their production, 22 PHs available on the market were analyzed for: (i) total amino acids concentration, (ii) free amino acids concentration, (iii) degree of racemization, (iv) degree of hydrolysis and (v) apparent average molecular size. The obtained results confirmed the inhomogeneity PHs. However, the chosen parameters were able to provide information about the above-mentioned correlation. Total amino acids in particular were useful for the identification of the original source material. The degree of racemization was useful for the identification of the type of hydrolysis used during production (chemical or enzymatic). The degree of hydrolysis and free amino acid concentrations were useful for the identification of the intensity of the hydrolytic process. The average molecular size was useful for the identification of polydispersity of the peptide size. In conclusion, the PHs can be adequately characterized only through a multi-analytical approach.
- total amino acids,
- free amino acids,
- racemization degree,
- degree of hydrolysis,
- average molecular size,
- peptides
Citation: Luciano Cavani, Alja Margon, Luigi Sciubba, Claudio Ciavatta, Claudio Marzadori. What we talk about when we talk about protein hydrolyzate-based biostimulants[J]. AIMS Agriculture and Food, 2017, 2(3): 221-232. doi: 10.3934/agrfood.2017.3.221

Related Papers:

Abstract

Protein hydrolyzates (PHs) are a well-known group of plant biostimulants that are obtained by thermal, chemical, enzymatic or mixed hydrolysis from animal or plant sources. PHs are mainly applied to plants with the aim to improve their nutrition level, stimulate metabolism, and increase resistance to abiotic stress. Chemically, the PHs are a mixture of free amino acids, oligo- and polypeptides. Considering the differences in the source materials and hydrolytic processes used for their production it is not surprising that PHs are a very complex and inhomogeneous category of biostimulants. This is a critical point that should be considered by both manufacturers and potential users of such products. With the aim to identify a putative correlation among PHs physic-chemical properties, the different source materials and the hydrolytic process used for their production, 22 PHs available on the market were analyzed for: (i) total amino acids concentration, (ii) free amino acids concentration, (iii) degree of racemization, (iv) degree of hydrolysis and (v) apparent average molecular size. The obtained results confirmed the inhomogeneity PHs. However, the chosen parameters were able to provide information about the above-mentioned correlation. Total amino acids in particular were useful for the identification of the original source material. The degree of racemization was useful for the identification of the type of hydrolysis used during production (chemical or enzymatic). The degree of hydrolysis and free amino acid concentrations were useful for the identification of the intensity of the hydrolytic process. The average molecular size was useful for the identification of polydispersity of the peptide size. In conclusion, the PHs can be adequately characterized only through a multi-analytical approach.

References

[1]	Calvo P, Nelson L, Kloepper JW (2014) Agricultural uses of plant biostimulants. Plant Soil 383: 3-41
[2]	European Biostimulants Industry Council, Economic over-view of the biostimulants sector in Europe. 2013. Available from: http://www.biostimulants.eu/wp-content/uploads/2013/04/ Biostimulant_economics_17April2013.pdf
[3]	Paradikovic N, Vinkovic T, Vrcek I V, et al. (2011) Effect of natural biostimulants on yield and nutritional quality: an example of sweet yellow pepper (Capsicum annum L.) plants. J Sci Food Agric 91: 2146-2152
[4]	Ertani A, Cavani L, Pizzeghello D, et al. (2009) Biostimulant activity of two protein hydrolysates on the growth and nitrogen metabolism in maize seedlings. J Plant Nutr Soil Sc 364: 145-158
[5]	Ertani A, Schiavon M, Muscolo A, et al. (2013) Alfalfa plant derived biostimulant stimulate short-term growth of salt stressed Zea mays L. plants. Plant Soil 364: 145-158 doi: 10.1007/s11104-012-1335-z
[6]	Colla G, Nardi S, Cardarelli M, et al. (2015) Protein hydrolysates as biostimulants in horticulture. Sci Hortic 196: 28-38 doi: 10.1016/j.scienta.2015.08.037
[7]	Friedman M (1999) Chemistry, nutrition, and microbiology of D-amino acids. J Agric Food Chem 47: 3457-3479 doi: 10.1021/jf990080u
[8]	Cunico R, Mayer AG, Wehr CT, et al. (1986) High sensitivity amino acids analysis using a novel automated pre-column derivatization system. Biochromatography 1: 6-14
[9]	Cavani L, Ciavatta C, Gessa C (2003) Determination of free L- and D-alanine in hydrolysed protein fertilisers by capillary electrophoresis. J Chromatogr A 985: 463-469 doi: 10.1016/S0021-9673(02)01733-8
[10]	Nielsen P M, Petersen D, Dambmann C (2001) Improved method for determining food protein degree of hydrolysis. J Food Sci 66: 642-646 doi: 10.1111/j.1365-2621.2001.tb04614.x
[11]	García Alvarez-Coque MC, Medina Hernández MJ, Villanueva Camañas RM (1989) Studies on the formation and stability of isoindoles derived from amino acids, o-phthalaldehyde and N-acetyl- L -cysteine. Anal Biochem 180: 172-176 doi: 10.1016/0003-2697(89)90107-3
[12]	Cavani L, Ter Halle A, Richard C et al. (2006) Photosensitizing properties of protein hydrolysate-based fertilizers. J Agric Food Chem 54: 9160-9167 doi: 10.1021/jf0624953
[13]	Yau WW, Kirkland JJ, Bly DD (1979) Modern size exclusion chromatography, Wiley-Interscience, New York.
[14]	R Core Team (2017) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available from: https://www.R-project.org/
[15]	Sosulski FW, Imafidon GI (1990) Amino acid composition and nitrogen-to-protein conversion factors for animal and plant foods. J Agric Food Chem 38: 1351-1356 doi: 10.1021/jf00096a011
[16]	Dawczynski C, Schubert R, Jahreis G (2007) Amino acids, fatty acids, and dietary fibre in edible seaweed products. Food Chem 103: 891-899 doi: 10.1016/j.foodchem.2006.09.041
[17]	Santi S, Zamboni A, Varanini Z, et al. (2017) Growth stimulatory effects and genome-wide transcriptional chages in protein hydrolysates in maize seedlings. Front Plant Sci 8: 433.

Reader Comments

Your name:*

Email:*
© 2017 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)