Comparison of oil compositions and antioxidant activities in safflower germplasm collected from East Asia

In order to select the potential genetic resources by evaluation of safflower germplasm, we investigated the oil compositions and antioxidant activities of 281 safflower accessions collected from East Asia. Total oil contents (TOC) were obtained by Soxhlet extraction and the fatty acid compositions (FAC) was analyzed by using gas chromatography. Antioxidant activities were measured the total polyphenol contents (TPC) [1], antioxidant activities of 1,1-diphenyl-2-picryl-hydrazil (DPPH) [2] and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) [3] using a spectrophotometer. The 281 safflower accessions were classified into five groups based on the complete linkage cluster analysis using their TOC, FAC, TPC, DPPH, and ABTS. The collections in group IV (43 accessions) were characterized as having higher antioxidant activities than other groups, while TOC and FAC were not high. TPC, DPPH, and ABTS of group IV showed variation from 61.70 ± 0.82 to 197.01 ± 2.28 µg GAE mg^-1 dw, 4.55 ± 0.15 to 14.30 ± 0.03 µg ASC mg^-1 dw, and 81.60 ± 1.60 to 195.66 ± 1.42 µg Trolox mg^-1 dw, respectively. The collections of group III (4 accessions) showed higher oleic acid contents with the average value 37.34% than other groups. DPPH activity had the significant positive correlation with ABTS activity (r = 0.910**). Oleic acid had significant negative correlation with linoleic acid (r =-0.973**). TOC contents negatively correlated with TPC (-0.105), DPPH (-0.138*), and ABTS (-0.162**). Principal component analysis (PCA) based on the oil compositions and antioxidant data revealed that the first two principal components (PC1 and PC2) together explained 96.4% of total variation. ABTS and TPC contributed much to the variation as compared to other analyzed variables. This study provides valuable information of safflower genetic resource which could be utilized in research of functional material.

Acknowledgements: This study was carried out from the support of "Research Program for Agricultural Science & Technology Development (Project No. PJ01011802)", National Institute of Agricultural Sciences, Rural Development Administration, Republic of Korea.

Keywords: Safflower, antioxidant activity, polyphenol content, oil, fatty acid.

References:

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