Characterisation of Rosa Mosqueta seeds: cell wall polysaccharide composition and light microscopy observations

The utilisation of enzymes for the extraction of vegetable oils from seeds has been a topic of growing interest in recent years. Knowledge of the cell wall polysaccharide composition is important to select the enzyme(s) neces sary for the most effective degradation of the cell walls. The purpose of t he present work is to characterise the seeds of Rosa Mosqueta (Rosa aff rub iginosa) by light microscopy (where several differential staining methods w ere applied to analyse the seed structure) and by the isolation of cell wal l polysaccharide extracts. The mature seed of Rosa Mosqueta has a very thic k and structurally complex seed coat comprising heavily lignified tissue. T he embryo has two cell layers of remaining endosperm tissue (indicating tha t this is an exalbuminous seed), two voluminous cotyledons that contain the oil, and bundles of provascular tissues distributed perpendicularly to the transverse axis of the embryo. The major non-cellulosic polysaccharides fr om the non-lignified tissues are glucuronoxylans and pectic polysaccharides ; glucans are also present in small amounts. The major non-cellulosic polys accharides from the lignified tissues are glucuronoxylans. Concerning the u se of enzymes for oil extraction, microscopy and cell wall polysaccharide a nalysis showed that the use of pectic enzymes followed by a xylanase or a c ellulase should be explored. (C) 2000 Society of Chemical Industry.