Changes in phytochemical content and antioxidant activity during inflorescence development in broccoli

Abstract

This study was performed to monitor glucosinolate (GSL) profile, total phenol, ascorbic acid, total flavonoid contents, and antioxidant activity in florets of six broccoli (Brassica oleracea L. var. italica Plenck) genotypes at three different inflorescence developmental stages. The level of phytochemicals and antioxidant activities varied significantly among genotypes and developmental stages. Out of the eight GSLs identified in this study, only five were present in all genotypes and their respective developmental stages. Glucoraphanin (GRA), a major GSL, was significantly increased towards the later stages of development (1.41 μg g-1 in immature stage of 'Koyoshi' to 10.57 μg g-1 in commercial stage of '09FA-M295'), whereas glucobrassicin (BRA) showed a reverse accumulation pattern with the highest value at the immature stage (5.10-7.97 μg g-1). Other minor GSLs varied depending on the genotype. Total phenolic and ascorbic acid content increased significantly as maturity progressed in all the genotypes with a relatively higher increment observed in ascorbic acid (65.8%-100.9%) than phenolic content (10.2%-31.2%). Flavonoid content, on the other hand, showed a cultivardependent accumulation pattern throughout the developmental stages. However, although antioxidant activity increased with inflorescence development, the increment was higher and lower than in total phenol and ascorbic acid content, respectively. The highest value for GRA (10.57 μg g-1), ascorbic acid (502.3 mg 100 g-1), total phenol (523.7 mg 100 g-1) and antioxidant activities was obtained for '09FA-M295' at the commercial stage. Taken together, these results indicate that phytochemicals in broccoli have a differential accumulation pattern during inflorescence development. Regardless of genotypes and inflorescence developmental stage, total phenolic content showed the highest correlation with antioxidant activity (r = 0.779**), followed by ascorbic acid (r = 0.674**) and flavonoid content (r = 0.602**), whereas total GSLs showed a nonsignificant correlation with antioxidant activity.

Pre- and Post-harvest Factors Affecting Glucosinolate Content in Broccoli

“…A linear increasing trend for 4-methylsulfinylbutyl-GL content throughout the development stages was instead reported by Rangkadilok et al ( 86 ) in three broccoli cultivars (Claudia, Marathon, and TB-234). In agreement with Rangkadilok et al ( 86 ), Bhandari et al ( 87 ) reported also a linear increase in 4-methylsulphinylbutyl-GL and a decreasing trend for 3-indolylmethyl-GL. However, the dynamic changes affecting 2-Phenylethyl-GL was cultivar-dependent.…”

“…Broccoli head development is an important factor in defining their phytochemical composition, as substantial changes arise at in this stage (72,87,88). However, such data is currently rather limited.…”

Natural colourants analysis and biological activities. Association to molecular markers to explore the biodiversity of Opuntia species

“…have also found that total polyphenol content varied among the thorn‐less and thorn‐containing cladodes varieties of cactus pear ( O. ficus indica ) (18.0 ± 0.5571.4 ± 2.4 mg GAE/g of DW). Thus, intraspecific differences and the degree of maturity have a direct impact on the phytochemical composition including phenol classes 38,39 …”

Evaluation of pigment, antioxidant capacity and bioactive compounds in microgreens of wheat landraces and cereals

“…Current results were higher than data of Chomchan et al (2016) on ricegrass and wheatgrass juices (35.62 ± 0.03 and 37.45 ± 0.98 mg TE g -1 DM extract) respectively, with the similar analysis (FRAP) method. The TAC capacities of six broccoli genotypes were determined between 20.1-34.6 μM g -1 in the immature and commercial periods by Bhandari et al (2019). It was determined that there was an increase of 62% between the two periods.…”

“…The fact that germination and sprouting are highly affected by different temperature, humidity and light conditions, this causes change in the TPC which makes it difficult to measure (Niroula et al, 2019b). The TPC of six broccoli genotypes were determined between 416.4 and 53.7 mg GAE 100 g -1 in commercial periods by Bhandari et al (2019). Similarly, Joaquín-Ramos et al ( 2020) found TPC in leaves, stems, roots and flowers of Barkleyanthus salicifolius between 6.82 and 48.21 mg QE g -1 dried extract and the highest in leaf.…”