Cell Ultrastructure of Kiwifruit （Actinidia chinensis） Shoot Tips During Cryopreservation

The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit （Actinidia chinensis Ganmi 5） during cryopreservation were investigated. Shoot tips were preserved in liquid nitrogen using vitrification, and the cell ultrastructure was examined using transmission electron microscopy （TEM）. The regular ultrastructure of the cell wall, cell membrane and nucleus of shoot tips could be damaged during the freezing and thawing associated with preservation using liquid nitrogen. The cell plasmolysis was increased and freezing tolerance was improved after precultufing and dehydrating in a preservation and vitrification solution （PVS2） （30% glycerol （Gly）＋ 15% ethylene glycol （EG）＋ 15% dimethylsulfoxide （DMSO） ＋ 0.4 mol L^-1 sucrose）. The structure of some cells with low degree of injury and reversible damage was similar to that of the control and they could undergo normal cell division and differentiation. Besides, they could recover automatically and regenerate after their reculture.     

Effect of traditional methods of processing on the electrophoretic patterns of faba bean water soluble proteins

A number of national dishes are prepared from the dry seeds of faba bean by soaking, germination (nabet), cooking (bisara and medammis) or frying a dough (falafel). Soaking (12 h) decreased the intensity of bands in the standard PAGE and increased the charge heterogeneity of neutral proteins in PAGIF. Germination (24 or 60 h) changed the patterns for esterases, peroxidases and amylases, but not for phosphorylases. The charge distribution of proteins was markedly changed in the basic region. Roasting did not affect the distribution in standard PAGE. All bands in the basic region of PAGIF disappeared. High MW-proteins wre degraded to low MW-proteins as seen in SDS-PAGE. The cooking broth and the cooked beans of nabet soup and medammis had more or less similar patterns in the standard PAGE. The broth of nabet soup had larger number of low MW-proteins than the bean extract in SDS-PAGE. Bisara proteins showed almost the same patterns as the corresponding proteins of the cooking broth of nabet soup. Falafel proteins showed patterns very similar to that obtained from roasted beans in the SDS-PAGE. PAGIF gave a different but characteristic charge distribution for falafel.