Metabolic changes of lipids & proteins during aging in terms of rooting response in mung bean (Phaseolus aureus Roxb.) cuttings

Abstract

Metabolic changes of lipids & proteins which occurs during aging of mung bean
(Phaseolus aureus) cuttings were studied. The decline in rooting response was coincided
with the decline of lipid & protein contents and verified by increasing the activity of
lipoxygenase & protease respectively. The data revealed the followings:-
1. A decline in rooting response of aged cuttings (held in distilled water for 3 days)
compared to fresh cuttings.
2. A significant increases in malondialdehyde (MDA) content by (88%), activity of
lipoxygenase by (277.2%) and activity of protease by (212.1%). Whereas the
proteins & antioxidants content (e.g. glutathione & ascorbate) were declined in
aged cuttings compared to fresh cuttings.
3. For controlling aging phenomenon, the cuttings were kept in anise (Pimpinella
anisum L.) seeds extract (1%), cinnamic acid (10-3M) & solutions of volatile oils,
which led to stop the processes that occurs during aging in terms of rooting
response by stopping the increase in MDA content, lipoxygenase activity &
protease activity, and maintaining protein & lipid contents as well as glutathione
& ascorbate contents.

The discussion was focused on enzymes that associated with lipid peroxidation &
the free radicals that produced by this process has increased during aging in terms of its
final product (MDA). In addition the role of ascorbic acid and glutathione as antioxidants
that involved in antioxidant defense mechanisms in terms of adventitious root formation
in cuttings were assayed.