A non-aqueous method for the sub-cellular fractionation of cotyledons from dormant seeds of Phaseolus vulgaris L.

A method is described for the sub-cellular ractionation of cotyledons from non-germinated Phaseolus vulgaris seeds in non-aqueous density gradients of potassium iodide in glycerol. The major organelles (protein bodies, cell walls and starch grains) are well resolved as adjudged by morphology and protein subunit patterns of gradient zones and are remarkably stable if water is rigorously excluded. The flexibility of the system is exploited in establishing the cytoplasmic location of the oligosaccharide fraction and in the large-scale preparative isolation of the sub-cellular components. The composition and morphology of the sub-cellular components are described and discussed.