Fig. 2

Seed mucilage that remains attached to P. ovata seeds after the application of various published extraction protocols and staining with 0.1% w/v ruthenium red. a The characteristic mucilage architecture of P. ovata seed mucilage. b After extended extraction in hot water the fine structure of the outer layer (OL) of mucilage has been lost leaving an inner adherent layer (IL). c The use of a chaotropic agent, KOH, significantly reduces the size of the mucilage envelope leaving only a film of mucilage that is resistant to chemical extraction. e Mucilage has been hydrolysed in situ and only a thin feathery layer remains. e Extraction by intense agitation leads to total mucilage removal. Scale = 1 mm