Go toArchive
Browse byFacets
Bookbag ( 0 )
'Ageing' in keywords
Results  4 Items
Sorted by   
Publication Year
1997 (1)
1996 (1)
1976 (2)
1Author    G. Kulandaivelu, D. 0. HallRequires cookie*
 Title    Stabilization of the Photosynthetic Activities of Isolated Spinach Chloroplasts during Prolonged Ageing  
 Abstract    Isolated spinach chloroplasts (type A complete) were used to study the changes in the pnoto-chemical activities upon storage in order to establish optimum conditions for prolonged storage. Chloroplasts stored at — 5 °C were found to retain over 70% of their photosynthetic electron transport from H20 even after 5 days. Increases in the level of state 2 electron transport (due to uncoupling) with concomitant loss of state 3 phosphorylation activity was observed during the initial period of ageing. Addition of 1% bovine serum albumin decreased the level of uncoupling and maintained the phosphorylation activity for a longer period. Chloroplasts stored at 77 °K main­ tained their phosphorylation capacity for a period of 10 days even after repeated freezing and thawing. Photosystem I activity was found to be more stable over the whole ageing period of 15 days. Loss of plastoquinone may be responsible for the decrease in electron transport between photosystems II and I. 
  Reference    (Z. Naturforsch. 31c, 452 [1976]; received August 22 1975/March 11 1976) 
  Published    1976 
  Keywords    Ageing, Stabilization, Photosynthetic Activities, Chloroplasts 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0452.pdf 
 Identifier    ZNC-1976-31c-0452 
 Volume    31 
2Author    G. K. Ulandaivelu An, D.0 H AllRequires cookie*
 Title    Ultrastructural Changes in in vitro Ageing Spinach Chloroplasts  
 Abstract    Ultrastructural changes in in vitro ageing spinach chloroplasts have been studied in detail. Prolonged storage caused swelling of the chloroplasts due to the increase in the thickness and spacing of the thylakoid membranes. The increase in the thickness of the membrane is partly ac­ companied by the release of lipids. Addition of crystalline bovine serum albumin was found to stabilize the membrane structures. Storage of the chloroplasts at 77 °K even though it resulted in complete breakage of the whole chloroplasts, maintained the thylakoid structures in a highly intact form. 
  Reference    (Z. Naturforsch. 31c, 82 [1976]; received August 8 1975) 
  Published    1976 
  Keywords    Ultrastructure, Thylakoid Membrane, Ageing, Storage Conditions, Spinach 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0082.pdf 
 Identifier    ZNC-1976-31c-0082 
 Volume    31 
3Author    ChristineA. Kraus, Gerhard SpitellerRequires cookie*
 Title    Phenolic Compounds from Ageing Shoots of Picea abies  
 Abstract    The influence of ageing on the amount and composition of phenolic compounds and their glucosides was studied in one to five-year-old shoots of Picea abies. The total content of phenolics increased remarkably within the first two years of growth. In this period cinnamic acid derivatives were dominating, but beginning with the end of the first vegetation period a dramatic increase of acetophenones was observed. Obviously at the end of the first vegetation period the cinnamic acid derivatives are subjected to oxidation resulting in an increase of acetophenones. 
  Reference    Z. Naturforsch. 52c, 308 (1997); received Decem ber 19 1996/January 23 1997 
  Published    1997 
  Keywords    Picea abies, Ageing, Phenolics, Phenolic Glucosides, Quantification by GC-MS 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/52/ZNC-1997-52c-0308.pdf 
 Identifier    ZNC-1997-52c-0308 
 Volume    52 
4Author    Werner Meyer, G.Erhard SpitellerRequires cookie*
 Title    Increase of Caryophyllene Oxide in Ageing Lemon Balm Leaves (Melissa officinalis L.) -A Consequence of Lipid Peroxidation?  
 Abstract    Oxidative processes, especially lipid peroxidation (LPO), are assumed to increase during ageing. In an attempt to provide experimental evidence for this assumption lemon balm plants (Melissa officinalis L.) of different age and location were analyzed for oxidatively caused changes in the etheric oil composition. The investigation revealed that the caryophyl­ lene oxide (CarO) content of lemon balm plants -a main constituent -depends on two factors: age and habitat. The content of CarO increased with age continuously up to a factor of 3. Poor nutritive conditions, as growth on unfertilized soil, also caused an increase in CarO content. Addition of Fe2+/ascorbate -enhancing oxidative processes -promoted the formation of CarO. Hydroperoxides of unsaturated fatty acids (L O O H s) in the lipid extract of lemon balm leaves were converted to corresponding hydroxy acids (LO H s) by sodium borohydride re­ duction. These were hydrogenated and subjected to GC/MS analysis after derivatisation. A surplus of 9-hydroxy-octadecanoic acid over the 13 isomer indicated at least in part enzymatic lipid peroxidation. Polarographie determination o f the oxygen consumption revealed a gen­ erally low but in ageing plants increased lipoxygenase activity. This indicates a contribution of lipid peroxidation in the epoxidation process of caryophyllene. 
  Reference    Z. Naturforsch. 51c, 651 (1996); received May 17/June 12 1996 
  Published    1996 
  Keywords    Melissa officinalis, Lemon Balm, Caryophyllene Oxide, Lipid Peroxidation, Lipoxygenase Activity, Ageing 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0651.pdf 
 Identifier    ZNC-1996-51c-0651 
 Volume    51