Phosphoric Acid-Mediated Depolymerization and Decrystallization of α-Cellulose Obtained from Corn Cob: Preparation of Low Crystallinity Cellulose and Some Physicochemical Properties

Purpose: Low crystallinity celluloses (LCC) are materials that have a substantially reduced degree of crystallinity, typically ranging between 15 and 45%. It is useful as an excipient in preparation of tablets and confectionery products. The aim of this work was to obtain from α-cellulose content of corn cob, a low crystallinity cellulose (LCC-CC), and study its physical properties as well as evaluation of its potential as tablet excipient. Methods: α- cellulose (AC-CC) obtained from corn cob by a delignification process, was depolymerized with 85% phosphoric acid to yield LCC-CC product, whose physical properties were compared with those of AC-CC. Results: The yield of AC-CC and LCC-CC were 14 and 11 %, respectively. The physical properties indicated a good level of purity of the cellulose materials as they conform to British Pharmacopoeia specifications. The flow indices, however, showed that these materials flowed poorly. Conclusion: It was concluded that LCC-CC is a potential disintegrant and filler-diluent, in pharmaceutical tableting. Keywords: Low crystallinity cellulose, α-cellulose, physical properties, corn cob. > Tropical Journal of Pharmaceutical Research Vol. 4 (2) 2005: pp. 509-51

Some Physical Characteristics of Microcrystalline Cellulose Obtained from Raw Cotton of Cochlospermum planchonii

Purpose: The microcrystalline cellulose is an important ingredient in pharmaceutical, food, cosmetic and other industries. This study aimed at evaluating the physical characteristics of microcrystalline cellulose (CP-MCC), obtained from the raw cotton of Cochlospermum planchonii. Methods: CP-MCC was obtained from the raw cotton by a two-stage sodium hydroxide treatment process followed by sodium hypochlorite bleaching and acid hydrolysis. It was examined for its physicochemical and powder properties. The powder properties of CP-MCC were compared to those of the well-known commercial microcrystalline cellulose grade, Avicel PH 101. Results: The extraction yield of CP-MCC was approximately 21%. The cellulose material was composed of irregularly shaped fibrous cellulose particles with a moisture content of 7.2% and total ash of 0.12%. The true density was 1.38. The flow indices showed that CP-MCC has poor flow. The hydration, swelling and moisture sorption capacities were 4.7, 83.3 and 22%, respectively. Conclusion: The cellulose product, CP-MCC, obtained from the raw cotton of Cochlospermum planchonii conformed to the official specifications in the British Pharmacopoeia (2004). The flow properties of a powder are critical in direct compression tableting; consequently, for the materials to be used for this purpose, it would require the addition of a glidant. Furthermore, the swelling parameters indicate that CP-MCC would be a better disintegrant than Avicel PH 101. Keywords: Cochlospermum planchonii, microcrystalline cellulose, physical characteristics, pharmacopoeial requirements> Tropical Journal of Pharmaceutical Research Vol. 4 (2) 2005: pp. 501-50

A Comparative Evaluation of the Flow and Compaction Characteristics of a-Cellulose obtained from Waste Paper

Purpose: Alpha-cellulose obtained as pulp from fibrous plant materials has found use in the pharmaceutical industry as a disintegrant and direct compression diluent. The aim of this study was to evaluate the suitability of α-cellulose obtained from waste paper as a direct compression excipient. Method: The flow and compaction characteristics of α-cellulose (ACP) obtained from waste paper, in comparison with Avicel PH 101, using the Kawakita and Heckel models were evaluated. Result: The results indicate that the flow properties of these materials could not be predicted accurately using the Kawakita model. A comparison of compression behaviour and compactibility of the two powders showed Avicel PH 101 to be a slightly better binder. Conclusion: It was concluded that ACP material could find use as a potential dry binder and direct compression diluent in tableting as the binding properties were comparable to those of Avicel PH 101. . Keywords: Alpha-cellulose, microcrystalline cellulose, flow and compaction characteristics, direct compression diluent. > Tropical Journal of Pharmaceutical Research Vol. 6 (1) 2007: pp. 645-65

Properties of microcrystalline cellulose obtained from coconut (Cocos nucifera) husk

This study was aimed at developing a pharmaceutical grade microcrystalline cellulose from coconut fruit husk fibre as a tablet excipient. The microcrystalline cellulose coded CH-MCC, was obtained from coconut (Cocos nucifera) fruit husk fibre by a two-stage sodium hydroxide delignification process followed by sodium hypochlorite bleaching and acid hydrolysis. CH-MCC was examined for its physicochemical and powder properties. The powder properties of CH-MCC were compared to those of best commercial microcrystalline cellulose grade, Avicel PH 101. The extraction yield of CH-MCC was approximately 19%. The cellulose material was composed of irregularly shaped fibrous cellulose particle with a moisture content of 6.2%. The true density was 1.53. The flow indices showed that CH-MCC flowed poorly. The hydration and swelling capacities were 3.15 and 48.6% respectively. The study revealed that the cellulose material compares favourably with Avicel PH 101 as well as official requirement specified in the British Pharmacopoeia 1993 for microcrystalline cellulose. Keywords: Coconut fruit fibre, microcrystalline cellulose, powder properties Journal of Pharmacy and Bioresources Vol. 3 (1) 2006: pp. 12-1

Microcrystalline cellulose obtained from

This study was aimed at developing pharmaceutical grade microcrystalline cellulose from Chasmanthera dependens stem phloem fibres as a tablet excipient. The microcrystalline cellulose coded CD-MCC, was obtained from the phloem fibres by a two-stage sodium hydroxide delignification process followed by sodium hypochlorite bleaching and acid hydrolysis. CD-MCC was examined for its physicochemical and powder properties. The powder properties of CD-MCC were compared to those of best commercial microcrystalline cellulose grade, Avicel PH 101. The extraction yield of CD-MCC was about 17%. The cellulose material was composed of irregularly shaped fibrous cellulose particle with a moisture content of 4.8%. The true density was 1.66. The flow indices showed that CD-MCC flowed poorly. The hydration and swelling capacities were 2.19 and 41.9% respectively. The study revealed that the cellulose material compares favourably with Avicel PH 101 as well as official requirement specified in the British Pharmacopoeia 1993 for microcrystalline cellulose Keywords: Chasmanthera dependens; Microcrystalline cellulose, Extraction; Characterization Journal of Pharmacy and Bioresources Vol. 3 (2) 2006: pp. 70-7