M. Lahaye et D. Jegou, CHEMICAL AND PHYSICAL-CHEMICAL CHARACTERISTICS OF DIETARY-FIBERS FROMULVA-LACTUCA (L) THURET AND ENTERMORPHA-COMPRESSA (L) GREV, Journal of applied phycology, 5(2), 1993, pp. 195-200
Dietary fibres from Ulva lactuca (L.) Thuret (sea lettuce) and Enterom
orpha compressa (L.) Grev. (A.O. nori) were measured according to a 's
tandard' method and a 'physiological' protocol simulating the gastric
and intestinal environments. U. lactuca contained 15.8-8.0% soluble an
d 24.2-32.6% insoluble fibres according to the 'standard' and 'physiol
ogical' methods, respectively. For E. compressa, these values were 14.
9-15.9 and 21.6-28.7 %, respectively. For both algae, the composition
suggests that the soluble fibres were xylorhamnoglycuronans sulphates
and insoluble fibres were essentially composed of glucans. No marked c
hemical compositional variation was observed between soluble fractions
extracted under the simulated gastric and intestinal conditions. Fibr
es in both algae are hydrophilic but the water holding capacities were
higher after extraction of soluble fibres (5.5-9.5 g g-1 for the dry
algae; 14.0-16.0 g g-1 for the standard insoluble fibres). Water solub
le fibres demonstrated low intrinsic viscosities at 37-degrees-C in bu
ffers, particularly those from E. compressa (36.0-36.5 ml g- 1), and w
as affected by pH for those of U. lactuca (147.5 ml g-1 at pH 3.0 and
175.0 ml g-1 at pH 7.3).