POSTHARVEST-RELATED CHANGES IN THE PHASE BEHAVIOUR OF MICROSOMAL MEMBRANES FROM CLOVES OF GARLIC (ALLIUM SATIVUM L.)

The phase behaviour of microsomal membranes from the storage leaf of garlic seed cloves has been examined by wide angle x-ray diffraction to analize the state of the lipid crystallization during the post-harvest period.

The diffractograms of the smooth microsomes show reflections at a Bragg spacing of 4.15 Å and 3.75 Å. Such reflections had the highest intensity immediately after harvest.
Then, intensities decreased until the minor value was obtained at 150 days.
During the sprout emergency state reflections were intensified up to about the 50 % of the highest value.
Data from the rough microsomal fraction were erratic and unreliable.
The characteristic peak of the liquid-crystalline phase (4.6 Å) was not observed in the studied membranes.

The results indicates that as dormancy progresses the proportion of lipid in gel phase in the storage leaf decreases.
This changed state of the lipid represents a substantial increase in membrane fluidity and may well be involved in the control of dormancy of garlic cloves.

I International Symposium on Edible Alliaceae

M.B. Pérez, C.A. Croci, O.A. Curzio

Alliaceae, x-ray diffraction, lipid crystallization, dormancy, sprouting, storage

https://doi.org/10.17660/ActaHortic.1997.433.50