101(1)_str11

 

ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 101, No. 1 (2014), p. 79–84
DOI  10.13080/z-a.2014.101.011

Amino acid composition of kolomikta actinidia (Actinidia kolomikta (Maxim. & Rupr.) Maxim) fruits of Lithuanian origin

Aurelija PAULAUSKIENĖ, Živilė TARASEVIČIENĖ, Audronė ŽEBRAUSKIENĖ

Abstract

Fruits of actinidia (Actinidia Lindl.) genotypes are known as a source of vitamins C and E, minerals, dietary fibre, various organic acids, carotenoids, flavonoids, and other useful compounds, but almost no data are available about proteins and amino acids content. The objective of the study was to determine the amounts of crude protein and amino acids in the fruits of kolomikta actinidia (Actinidia kolomikta (Maxim. & Rupr.) Maxim.) cultivars. Four Lithuanian cultivars ‘Laiba’, ‘Lankė’, ‘Landė’ and ‘Paukštės Šakarva’ were investigated. The cultivars were developed at Aleksandras Stulginskis University’s research orchard and have been under investigation there for 25 years. The amount of crude protein was determined by the Kjeldahl method. Amino acids were separated by ion-exchange chromatography and detected photometrically. The crude protein content of the investigated kolomikta actinidia fruits ranged between 0.96–1.32%. There were no significant differences in the protein content among the cultivars tested. The protein content of kolomikta actinidia fruits is similar to that of another species of actinidia – kiwifruits (Actinidia chinensis Planch. (A.Chev) C.F.Liang & A.R.Ferguson). In kolomikta actinidia fruit, glutamic acid was the predominant amino acid with values ranging from 7.60 to 9.51 g kg-1. The highest amount of essential amino acids was in ‛Laiba’ fruits (17.71 g kg-1), while that of nonessential amino acids in ‛Lankė’ fruits (33.24 g kg-1). The recommended ratio of total essential amino acids to the total amino acids, protein efficiency ratio, amount of total nonessential, sulphur, aromatic, neutral, acidic, basic, branched chain amino acids, leucine/isoleucine ratio and their percentage levels in the fruits of all cultivars were calculated. The study showed that amino acids amounts and percentage levels in kolomikta actinidia fruits tested are similar to those in kiwifruits.

Key words: Actinidia, biological value of proteins, essential amino acids, nonessential amino acids, protein efficiency ratio.

Full text: 101_1_str11.pdf