https://www.selleckchem.com/products/Novobiocin-sodium(Albamycin).html The results demonstrated that certain cellular features contributed to decreased oxygen diffusion among the organs, specifically, those found in the leaf-rhizome and root-rhizome interfaces as well as the suberin and lignin layers in these regions. Additionally, our experiments with a catalase activator and inhibitor validated that a significant amount of the oxygen released in radial oxygen loss could not, in fact, be exclusively supplied by the atmosphere. Thus, a complementary model is proposed in which catalase activity is an important component of radial oxygen loss.Salt stress adversely affects plants by causing osmotic and ionic imbalance. Cellular osmotic adjustment occurs by modulation of water fluxes. Polyamines (PAs) are often advocated to be involved in osmoregulation during stressful conditions, and thus, they serve as potential "osmolytes." Aquaporins (AQPs), the water-transporting channels, are expected to play crucial roles in osmoregulation. Present investigations on etiolated sunflower seedlings demonstrate a possible correlation between PA homeostasis and maintenance of water balance, as a function of modulation of the abundance of two major AQP subfamilies PIP2 (plasma membrane intrinsic protein 2) and TIP1 (tonoplast intrinsic protein 1). Salt stress (120 mM NaCl) restricts growth of sunflower seedlings and induces reduction in relative water content (RWC). This accompanies enhanced abundance of PIP2s and TIP1s in seedling roots and that of TIP1s in cotyledons, as revealed by Western blot analysis of AQP isoforms and also their imaging by confocal laser scanning microscopy (CLSM). Raising seedlings in the presence of 500 μM of DFMA (DL-α-difluoromethylarginine) or DFMO (DL-α-difluoromethylornithine), which are potent inhibitors of PA biosynthesis enzymes (arginine decarboxylase (ADC) and ornithine decarboxylase (ODC), respectively), significantly promotes root extension, irre