Seeds of eight different accessions (TT-00, UAG/1907C, ELG/1907C, ELG/1907B, WPK/2007, KF-14, KF-05A, KF-03) of CG were obtained from the Centre for Biodiversity Kenya Resources Centre for Indigenous Knowledge, National Museums of Kenya, and germinated in a growth chamber at the SMART FARM in KIST (Gangneung, Korea). The seeds were sown in 200 holed trays with soil at a pH of 5-7, volume density = 0.3, and E.C < 1.0 ds/m at a temperature ranging between 25 and 30 ℃, humidity 60-80%, and 16/8 h day/night condition. After 1 week, the germinated plants were transplanted to pots and transferred to the greenhouse, whose temperature conditions were maintained at 20-25 ℃. Sampling was done at vegetative, flowering, and seed set stages of the plant, and the various organs of the sampled materials were separated into roots, flowers siliques, and a combination of leaves and stem (LS).

There were significant interaction effects of growth stages and accessions that contributed to changes in compounds content and AOA. TPC accumulated in plant generative parts, whereas flavonoids accumulated in young plant organs. HPLC profiling revealed that rutin was the most abundant compound in all organs, with flowers having the highest levels, while astragalin was only found in flowers. Silique extracts, particularly accession KF-14, recorded the highest TPC, which corresponded to the strongest radical scavenging activity in ABTS and DPPH assays and a strong linear correlation. The germplasm contained accessions with significantly different and varying levels of bioactive compounds and AOA. These findings potentiate the exploitation of CG organs such as siliques for AOA, flowers for rutin and astragalin, and young shoots for flavonoids. Moreover, the significant accumulation of the compounds in particular accessions of the germplasms suggest that such superior accessions may be useful candidates in genetic breeding programs to improve CG vegetable.