High Throughput Screeening of Flax (Linum usitatissimum L.) Cyclolinopeptides
Flax (Linum usitatissimum L.) seed is a rich source of potentially valuable cyclic peptides (CLs). The current research investigated the genotypic and environmental variation of CLs expressed in the Flax World Core Collection by means of high-throughput extraction and rapid HPLC analysis. The collection is a representative subsample of the widest diversity of flax gene resources. The performance of monolithic and microparticulate HPLC columns were compared for their efficiency in rapid reversed phase liquid chromatographic separation of CLs. CL analysis time was reduced to 1.5 min at a flow rate of 3.0 mL•min-1 using a monolithic Chromolith® SpeedROD. The column performed over 2000 injections without measurable changes in performance under these conditions. The optimum extraction conditions of CLs were also established. Total CL content was proportional to sum of UV absorbance (mAU) of the observed peptide chromatographic peaks at 214 nm. The total mAU of samples extracts from core collection samples planted in Saskatoon ranged from 71.4 to 223.7 mAU with a mean value of 153.5 ± 24.3 mAU ( + SD), whereas the total mAU from samples grown at the Morden site ranged from 96.2 to 243.6 mAU with a mean value of 171.3 ± 24.0 mAU. The highest total CL content was observed in cultivar ‘AC Watson’, whereas, ‘Primus’ and an unnamed accession (CN 101580, TMP 10121) exhibited the highest ratio CLs expressed by NCBI gene sequence AFSQ01016651.1 to peptides expressed by gene sequence AFSQ01025165.1. In contrast, the lowest total CL content and ratio of these gene products was observed in ‘Hollandia’ and ‘Z 11637’. No correlation between CL content and plant height, stem branching, petal colour, seed colour, seed weight, seed oil content, or α-linolenic content was evident. In addition to the known peptides, novel peptides 1-Met-CLN, 1-Mso-CLN, and 1-Msn-CLN were identified from ‘Hollandia’ and ‘Z 11637’. The variation of CL content and composition of flaxseed from the core collection reveals that genetics may benefit flax breeding programs by allowing the selection of flax accessions with improved composition and functional properties.
Cyclolinopeptides, Flax, High throughput, Liquid chromatography, Monolithic columns
Master of Science (M.Sc.)
Food and Bioproduct Sciences