The Effect of Harvest Maturity Stage on ACC Synthase Activity and Total Proteins Profile in Kiwifruits during Normal and Controlled Atmosphere Storages
This study indicated that the harvest periods related to soluble solids contents (SSC) content of Hayward kiwifruit significantly affected 1-aminocyclopropane-1-carboxylate (ACC) synthase activity, total soluble protein (TSP) content and protein profile. ACC synthase activity was suppressed, especially in early harvested fruits, by an inhibition of fruit ripening during controlled atmosphere (CA) storage. Separation of TSP using denatured polyacrylamide gel electrophoresis (SDS-PAGE) revealed that one predominant polypeptide with 38 kDa molecular mass that varied among four different harvest periods during normal atmosphere (NA) storage. This polypeptide band was accumulated with increased harvest maturity during NA storage. On the other hand, it was not detected on SDS-PAGE of CA samples. Consequently CA storage suppressed expression of the 38 kDa protein band, which may be responsible for ACC synthesis. SSC of kiwifruits at harvest is an important factor that effects the molecular changes related to ripening of fruits during storage.