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Successive extractions of de-waxed Carex meyeriana Kunth with distilled water, 0.25% NaOH-70% ethanol solution, 0.5%, 1%, 1.5%, 2% and 3% NaOH aqueous solutions at a solid–liquid ratio of 1:25 (g mL–1) at 80 °C for 3 h released 5.8%, 16.7%, 18.9%, 13.1%, 15.7%, 12.8% and 14.1% of the original hemicelluloses, respectively. The GPC analysis showed that the weight-average molecular weight (Mw) of alkali-soluble hemicelluloses was obviously higher than that of watersoluble hemicelluloses (16690 g mol–1) and with the increasing of alkali concentration the Mw increased from 34620 to 106210 g mol–1. Comparison of these hemicellulosic indicated that more branched and smaller molecular size of hemicelluloses fractions (xylose 5.6%) were more easily extracted by the hot water treatment. While the alkali-soluble hemicellulosic fractions contained less branched and larger molecular size of the …