Film formation and some structural features of hemicellulose fractions from Pinus densiflora leaves

Autor: Tomoko Shimokawa, Atsushi Kato, Noriko Hayashi, Eiji Togawa, Koichi Kakegawa
Rok vydání: 2014
Předmět:
Zdroj: Journal of Wood Science. 61:53-59
ISSN: 1611-4663
1435-0211
DOI: 10.1007/s10086-014-1440-0
Popis: Biodegradable translucent and transparent films were prepared from the hemicellulose fractions of Pinus densiflora leaves without using substantial amounts of additives. These fractions were isolated by alkaline extraction using 10 % sodium hydroxide after delignification by sodium chlorite, and precipitated with 80 % ethanol. The water-soluble fraction of the P. densiflora hemicellulose was mainly composed of arabino-4-O-methylglucuronoxylan according to a sugar analysis and NMR spectroscopy. The water-insoluble fraction contained more mannan-related polysaccharide than water-soluble fraction. Whole hemicellulose and the water-insoluble fraction formed stable films when they were dispersed in water, cast into petri dishes without additives, and dried. The water-soluble fraction formed the most transparent film, and it required a 1 % (w/w of polysaccharide) lecithin additive, while it was peeling off from the dish to be used as a self-supporting film. The 10–12 μm thick films had an average tensile strength of 36–43 MPa, and 2.1–2.5 % elongation at break. In the long wavelength, the light transmission was high in the order of water-soluble, whole hemicellulose, and water-insoluble fraction. P. densiflora leaves have a history of being edible; thus, the leaves of this tree can produce a useful and edible hemicellulose film.
Databáze: OpenAIRE
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