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Highly purified cellulose was separated from wheat straw by sequential treatments of dewaxed straw with 0.5-M aqueous KOH at 35°C for 2.5 h under ultrasonic irradiation time of 0 to 35 min, 2% H2O2–0.2% TAED at pH 11.8 for 12 h at 48°C, and with 80% acetic acid–70% nitric acid (10/1, v/v) at 120°C for 15 min. The yield of crude cellulose preparations obtained by first two-stage treatments ranged between 45.3% and 46.9% of the dry weight straw which contained 7.3 to 7.9% residual hemicelluloses and 3.3 to 3.7% residual lignin, and had molecular weights ranging from 269,960 and 258,280 g mol−1 determined by their viscosity, while the purified cellulose samples separated by a further treatment of the corresponding crude cellulose with 80% acetic acid–70% nitric acid, are relatively free of bound lignin (0.1 to 0.2%) and contained minor amounts of associated hemicelluloses (∼3%), but gave much lower molecular weights ranging between 42,300 and 44,650 g mol−1 estimated by GPC in DMAc/LiCl system indicating that the final step treatment with 80% acetic acid–70% nitric acid resulted in a noticeable degradation of the cellulose except for removal of residual hemicelluloses and lignin. However, there was no evidence of increased acid or aldehyde by oxidation in all the purified cellulosic preparations. Both crude and purified cellulose samples were characterized by FT-IR and CP/MAS 13C-NMR spectroscopy. The thermal stability of the purified cellulosic preparation was higher than that of the crude cellulosic sample. [ABSTRACT FROM AUTHOR]

Successive extraction of sago pith with cold water, hot water, dimethylsulfoxide, and 5% NaOH yielded 48.9% cold-water-soluble starch, 11.5% hot-water-soluble starch, 21.9% DMSO-soluble, starch, and 7.1% alkali-soluble starch, which contain 5.4%, 7.0%, 3.6%, and 16.2% nonstarch polysaccharides, such as β-glucan and hemicelluloses, respectively. The total pure starch accounted for 83.9% of the dried sago pith. Cold and hot-water-soluble starches contained noticeable amounts of amylose, whereas DMSO- and alkali-soluble starches predominated in amylopectin. All the four starch fractions also contained trace quantities of ash (0.05%-0.4%), crude protein (0.1%-0.15%), and lipids (0.1%-O. 16% ). The isolated straches were further analyzed by U V, FT-IR, and [sup13]C-NMR spectroscopies as well as thermal analysis, and the results are reported. [ABSTRACT FROM AUTHOR]

The article focuses on the solutions made by the National Non-Food Crops Centre (NNFCC) towards the food versus (vs) fuel situation in Great Britain. It states that it has driven the need for a sharper focus on biomass, by-products and renewable wastes streams than ever before. In this context, NNFCC is producing a road map for advanced fuels and a techno-economic evaluation of emerging alga oil technologies. On the waste-to-energy side it is reviewing the potential for gasification of waste. It also examines the co-digestion of biodegradable packaging and food waste by anaerobic digestion.