Pawadee MethacanonOraphin ChaikumpollertParjaree ThavornitiKrisda SuchivaThailand National Metal and Materials Technology CenterMahidol University2018-07-242018-07-242003-11-01Carbohydrate Polymers. Vol.54, No.3 (2003), 335-342014486172-s2.0-0141996414https://repository.li.mahidol.ac.th/handle/123456789/20801Chemical composition of two ecotypes of the Vetiver grass (Vetiveria zizanioides nash) leaves has been investigated using the gravimetric method. The principal polysaccharides found in samples were hemicelluloses (ca. 38%), followed by cellulose (ca. 27%). Protein content determined by bicinchoninic acid assay using bovine serum albumin (BSA) as a standard was approximately 5%. Lignin content determined by acid chlorite method was approximately 10%. Ash content was 3% consisting of mainly silica (ca. 50%). The obtained hemicelluloses with the molecular weight of 30,000 showed the decomposition temperature at 310 °C. In order to determine an optimum condition for extraction of hemicelluloses, effects of process parameters: alkaline type (NaOH, KOH, Ca(OH)2and Ba(OH)2), alkaline concentration (0.025-4 M), extraction time (2-18 h) and temperature (25-60 °C) were studied. It was found that all parameters influenced on the hemicellulose yield and properties in various degrees. Finally, an optimum condition giving a maximum yield of 35% hemicelluloses was recommended as 4 M NaOH at ambient temperature for 8 h. © 2003 Elsevier Ltd. All rights reserved.Mahidol UniversityChemistryMaterials ScienceArticleSCOPUS10.1016/S0144-8617(03)00182-6