Phenolic acids in kernels of different coloured-grain wheat genotypes

Abstract

The content of free, conjugated and bound phenolic acids in 12 wheat (Triticum aestivum L.) genotypes of 4 different grain colours (standard red, yellow endosperm, purple pericarp and blue aleurone) from 2-year field trial was analysed in the present study. Significant increase (8%) in the total phenolic acid content was observed in the dryer year 2017. Five phenolic acids (ferulic, sinapic, p-coumaric, vanillic and 4-hydroxybenzoic) and cis-isomers of ferulic and sinapic acid were determined by HPLC-DAD (high-performance liquid chromatography with a diode-array detector) in grain samples. The total phenolic acid content of coloured wheat groups varied: blue aleurone > purple pericarp > yellow endosperm > red colour (798 > 702 > 693 > 599 µg/g). The fraction of bound phenolic acids was the major contributor to the total phenolic acid content (91.7%) with ferulic acid predominating (85.2%). Conjugated phenolic acids accounted for 7.9% of the total with sinapic and ferulic acid predominating (47.6% and 19.9%). The composition of individual phenolic acids was similar within these two fractions. The remaining 0.4% was represented by the fraction of free phenolic acids in which the phenolic acid profile varied among the individual coloured groups. Ferulic acid prevailed in red and yellow wheats, vanillic in blue and p-coumaric in purple wheats.

Phenolic Acid Profiles and Antioxidant Activity of Major Cereal Crops

“…Paznocht et al [ 8 ] published the TPC of coloured wheat in the range 599–798 μg GAE/g. In the study of Legzdina et al [ 6 ], TPC in hulless and hulled spring barley ranged between 817 and 1401 μg GAE/g, while Šimić et al [ 33 ] reported TPC content in hulled barley in the range from 1270–1670 μg GAE/g dm .…”

“…Phenolic acid (PA) profiles and the content of whole grain or grain fractions have mainly been studied in wheat and to a limited extent in barley and corn, so comparison of phenolic acid profiles of major cereal crops under similar experimental conditions is needed [ 5 ]. Despite relatively high genetic impact, some authors have shown that environment factors, including weather conditions during the growing period (water and temperature stress), have a strong influence on the selected health-beneficial components of cereals and their antioxidant properties [ 6 , 7 , 8 ]. Cereal varieties developed in recent years have been more oriented to crop yields and height, timing of crop maturation, protein content, and disease and pest resistance.…”

Optimizing methods to characterize caffeic, ferulic, and chlorogenic acids in Salicornia sinus-persica and Salicornia bigelovii extracts by tandem mass spectrometry (LC-MS/MS)

“…The most abundant phenolic acid detected in the water extract from S. bigelovii was chlorogenic acid (240.98 µg/g ± 9.40 µg/g), whereas the water extract from S. sinus-persica was the most abundant in ferulic acid (75.70 µg/g ± 10.77 µg/g). S. bigelovii was found to contain a phenolic acid content comparable to that of common cereal (70 µg to 90 µg phenolic acids/g) (Manach et al 2004) coloured wheat (599 to 798 µg phenolic acids/g) (Paznocht et al 2020), opuntia fruits (58 μg phenolic acids/g) (Oniszczuk et al 2020) and some types of apple (333 µg to 3333 µg phenolic acids/g) (Manach et al 2004). Despite the fact that this number is lower than in some other plants such as green coffee beans (55000 µg to 100000 µg phenolic acids/g) (Ohiokpehai 1982) or blueberry (13000 µg phenolic acids/g) (Manach et al 2004), Salicornia species contain a combination of three acids (caffeic, ferulic, and chlorogenic), which may add to their therapeutic properties.…”

Antioxidant activity and content of selected antioxidant compounds in grain of different oat cultivars

“…Total phenolic acids content (TPA). The TPA analysis was carried out according to the method of isolation of bound phenolic acids previously published by Paznocht et al (2020). This extraction method is suitable for the determination of the TPA when applied to the raw cereal material without previous steps specific to other phenolic acid fractions (free and conjugated).…”