AMINO ACID PROFILE OF PHASEOLUS VULGARIS PODS AND DRY EXTRACT PREPARED OF THEM
Authors: Vronska L. V. , Demyd A. Ye. 
Published: April 2019

The aim of the research was to study the amino acid profile of the phaseolus vulgaris pods and extract prepared of them.

Materials and methods. Five samples of raw material of phaseolus vulgaris pods (erect herbaceous bushes varieties with white seeds) were collected in the Ternopil and Volyn regions, dry extract of phaseolus vulgaris pods was obtained according to previously developed technology. The study of amino acid composition of the raw materials of phaseolus vulgaris pods and extract prepared of them was carried out using a thin-layer chromatography (TLC) and a high-performance liquid chromatography (HPLC).

Results and discussion. The better separation of amino acids in TLC-research of the raw material of phaseolus vulgaris pods was observed in the system of solvents isopropanol - formic acid - water (40: 2: 10). As a result of the study, aspartic and glutamic acids, glycine, valine, tyrosine and leucine were identified.

The amino acid profile of the studied samples of raw material is quite homogeneous in composition: 7 essential amino acids (histidine, threonine, valine, methionine, phenylalanine, isoleucine and leucine) and 8 non-essential amino acids (aspartic and glutamic acids, arginine, serine, glycine, alanine, tyrosine and proline); lysine was found among the bound amino acids in the 4th sample of raw material. Proline predominates in all samples of raw materials among free amino acids. Among the bound amino acids the content of glutamic acid, which is the product of the glutamine hydrolysis, is the highest. The content of glycine, serine and alanine is also high. Among the essential amino acids, leucine, phenylalanine, histidine, threonine, isoleucine, valine were determined in content descending order.

The quantitative determination of amino acids in the extract of phaseolus vulgaris pods proved that the content of proline was the highest (12.47 mg / g); the content of some compounds was also high: aspartic (5.41 mg / g) and glutamic (3.41 mg / g) acids, arginine (5.10 mg / g; both in free and bound forms), glycine (1.02 mg / g) and serine (1.04 mg / g). Among the essential amino acids in the extract, the amount of valine (0.80 mg / g), phenylalanine (0.67 mg / g), threonine (0.66 mg / g), leucine (0.63 mg / g) and isoleucine (0.58 mg / g) was a little different. The total content of amino acids in the extract was 3.2%.

Conclusions. 1. The amino acid profile of five samples of phaseolus vulgaris pods was studied by the HPLC method. It has been established that the composition is quite homogeneous, and the total content varies within 0.7-1.1%.

2. In the dry extract of phaseolus vulgaris pods the content of 5 essential and 7 non-essential amino acids has been determined. The content of free amino acids in the extract is 0.52%; the total content of free and bound amino acids is 3.2%.

3. When studying the stability and establishing the shelf life of the dry extract of phaseolus vulgaris pods, it is necessary to take into account the presence of free amino acids and protein substances.