Principle component analysis of isoflavone content in hybrid soybean genotypes

The beneficial health effects of soybean products are due to the presence of isoflavones, components with estrogen like activity [1]. The aim of this assay was to quantify the content of isoflavones in hybrid soybean genotypes and to investigate whether this trait can be transmited from parent genotypes to its hybrids.

Twenty different soybean genotypes used in this assay were cultivated on experimental fields at the Institute of Field and Vegetable Crops, Novi Sad. After extraction with methanol-water (8/2, v/v), isoflavone content was determined by C₁₈ reversed phase high-performance liquid chromatography coupled with photodiode array detector [1].

Content of total isoflavones in analyzed samples ranged from 1.56 to 3.66mg/g soybean and the average was 2.59mg/g soybean. Ten of twenty analyzed hybrids had one same parent genotype, previously found to be abundant in content of isoflavones [unpublished results]. These ten samples had higher values of isoflavone concentrations (3.14mg/g soybean in the average) in comparison with the other ten (2.14mg/g soybean in the average). Similarity of the hybrids with the one same parent genotype was confirmed by Principal Component Analysis performed in SPSS 10.0 (Figure 1) where it can clearly be seen that these hybrid genotypes (placed in upper ellipse) distinguish from the rest. The results suggest that content of isoflavones is the trait that can be transmited from parent genotypes to its hybrids and therefore the breeding of genotypes with better healthpromoting characterictics can be directed.

Figure 1. Diagram of genotypes obtained by Principle Component Analysis

Acknowledgements: Ministry of Science, Republic of Serbia

References: 1. Lee, J., Renita, M. et al. (2004)J. Agric. Food Chem. 52:2647–2651.