Why Terra-Sorb®? Some facts about L-α-amino acids obtention and properties

It is widely accepted that the application of L-?-amino acids under abiotical stress conditions (e.g. cold, drought, high temperatures…) is beneficial and improves plant recovery and performance, by inducing stomata to open under stressful conditions, resulting in a net increase in photosynthesis. Soil applications of L-?-amino acids also promote greater absorption and translocation of nutrients by roots.  Other positive effects include the protection of cell macromolecules and the neutralization of free radicals, thanks to their antioxidant activity.
 
Why L-?-amino acids?
In all living organisms, L-?-amino acids are the only biologically active form of amino acids that withhold all these different functions. Thus, the exogenous application of a Biostimulant product based on L-?-amino acids is a supplement that allows the crop to save energy during its physiological processes.
However, while L-amino acids are biologically active, the metabolism role of D-amino acids in plants is still doubtful, and the few existing studies on this topic indicate undesired agronomic effects such as growth inhibition or apparent toxicity. Therefore, the presence of D-amino acids in these kinds of products may be considered as a negative indicator of the purity and quality of the biostimulant.
 
Production methods
Extracting method of amino acids will determine the amount of L and D amino acids in the obtained product: Enzymatic hydrolysis, the natural process used for manufacturing Terra-Sorb® products, does not cause racemization (conversion from L to D forms). In contrast chemical hydrolysis consists on the use of strong agents (acids or alkali) and high temperatures leading to extreme pH’s. Consequently, chemical hydrolysis produce some racemization of L-amino acids to D-amino acids (Fig. 1), resulting in loss of product activity.

Fig 1: Scheme between the basic difference between Chemical and Enzymatic Hydrolisis
Although this had been widely recognized during many years, it has been recently assessed analytically in University of Alcalá, Spain and published in Journal of Agricultural and Food Chemistry (Sánchez-Hernandez et al. 2013). The results showed how Terra-Sorb® showed the lowest values of racemization (all 100% L-form) while the Standard product contained high proportion of undesired D-AA.

Fig.2 Enantiomeric Excesss comparing Terra-Sorb Foliar with a product declaring similar content of free amino acids. Four marker amino acids where monitored in this study (Lys, Asp, Glu, Ala)
Enzymatic hydrolysis also provides a rich and varied aminogram compared to the other methods. This happens because most labile aminoacids are preserved in this process, as it is less aggressive.
 
Terra-Sorb®: A complete aminogram
Terra-Sorb, produced by enzymatic hydrolysis contains all the18 amino acids that are present in proteins. Unlike this, under chemical hydrolysis conditions, most labile amino acids such as tryptophan, histidine, cysteine and methionine are significantly reduced or destroyed. This is relevant because different amino acids fulfill different functions in plant metabolism, so by providing only some of them, plant needs under stress recovery are not completely covered.  In such situation the plant will still need to synthetize lacking amino acids from the provided ones, spending time and energy and consequently causing a slower and less efficient response to stress.
For this reason, complete and balanced aminograms, such as the ones obtained in enzymatic hydrolysis for Terra-Sorb®, reinforce in a effective and rapid way all stress recovery pathways.
 
Cultivating our experience
Since the first Terra-Sorb® product was launched in the market almost 30 years ago, more than 1000 agronomical and scientific trials prove the beneficial effects of Terra-Sorb® high quality L-?-amino acids applications in all kind of crops. They had been performed by Bioiberica R&D team, prestigious Research Centers, Agronomical stations and Universities worldwide and some available at www.plantstress.bioiberica.com.
Being nowadays marketed in more than 60 countries, current Terra-Sorb® range, consists of: Terra Sorb® radicular, used through drip irrigation and intended to enhance nutrient absorption and root system growth; Terra-Sorb® Foliar for a fast stress recovery, proved to enhance photosynthesis and chlorophyll content and Terra-Sorb® Complex a high performance amino acids formula with micronutrients for severe stress recovery and a powerful biostimulation.