|
Bamboo biomass resources as an important one, with a wide distribution, fast growth and use more features in the biomass-based energy and materials have a higher value in use. The chemical composition of bamboo mainly of cellulose, hemicellulose, lignin and lipids, the chemical composition of these fossil resources for alternative, energy conservation, low-carbon economy and increase farmers' income has important significance. This study (1) using the medium length capillary column gas chromatography temperature for four kinds of bamboo (affinis, hard head Chuk, longevity bamboo and red shell praecox) methanol - chloroform (1:1, v / v) extract of fatty acids, sterols, waxes, sterols esters and glycerol esters such as the five components of step 54 kinds of compounds isolated and their structures were characterized by the simultaneous determination of phenolic compounds in lipids. (2) use of water, 0.5%, 1%, 1%, with 60% ethanol, 3%, 5% and 8% NaOH at the solid-liquid ratio 1:20 g / ml extraction temperature 60 oC continuous thunder red shell after dewaxing bamboo lignin, its chemical composition were studied and characterized structure. (3) research (2) to extract hemicellulose chemical composition and structure were studied. This series of results are as follows: 1. Lipid: lipid four kinds of bamboo main chemical composition of the free fatty acid (6.49-29.15%), glycerol esters (0.83-10.50%), waxes (0.25-4.72%) and sterol (1.03-3.92%), in addition, it also contains some non-ester compounds: phenolic compounds (0.86-4.77%), azelaic acid (0.90-5.95%) and maleic acid (0.67-3.12%) and small amounts of polysaccharides . Wong Chuk hard head extracts of the highest yield (5.98%), the yields Neosinocalamus lowest (4.22%), while the Life of bamboo extracts lipid content was highest (54.79%). 2 lignin: Continuous pumping lignin proposed sum accounted for 62.26% of the original lignin, seven kinds of very low lignin component contains neutral sugars (0.01-1.11%) and a small amount of p-coumaric acid esterification (0.08 -2.37%) and ferulic acid (0-1.69%) and etherified p-coumaric acid (0.02-0.65%) and ferulic acid (0.01-0.27%), the molecular weight range of 970-3430 g / mol between . Secondly, bamboo lilac unit is mainly lignin, accompanied by a certain amount of guaiacyl units and a small amount of p-hydroxyphenyl propane, between units mainly β-O-4 linkage, in a small amount of β-β and β-5 connection. 3 hemicellulose: Continuous extraction of hemicellulose obtained representing the sum of the original 80.1% of hemicellulose, the molecular weight of 3760-36000 g / mol between. Sugar analysis confirmed that the main component of water-soluble hemicellulose is glucose and the main component alkali-soluble hemicellulose is xylose, arabinose and glucuronic acid. 1 sup> H, 13 sup> C NMR and 2D-HSQC research showed 3% and 8% NaOH solution, extracted hemicellulose is poly-O-acetyl-4-O- methyl glucuronic acid - arabinose, xylose, and the first identification of the alkali-soluble red shell praecox hemicellulose structure: → 4) [4-O-methyl-α-D-glucuronic acid, - (1 → 2)] [2-O-acetyl group] [2,3 - di-O-acetyl group] [α-L-arabinose - (1 → 2)] [α-L-arabinose - (1 → 3) ]-β-D-xylose - (1 →.
|