CELLULOSE -GREEN AGROCHEM

MCC as Wet Granulation Filler : MCC is one of the very few types of filler with water insoluble yet hydrophilic properties with swelling tendencies (other examples being calcium pectinate and sodium alginate) and excellent water imbibing or wicking action. This is what makes it an excipient of choice in wet granulation procedures. Both Avicel PH 101 and PH 102 can be used advantageously as fillers in wet granulation in a recommended level of 5-15%. When used as a wet massing adjunct, the wicking action of MCC promotes rapid and even wetting of the powder mix. An advantage of its use in wet granulation is its ability to retain water, which makes the wet mass less sensitive to overwetting due to an excess of granulating fluid. The milling of the wet mass is easier due to less clogging of the screen that produces a more uniform granulation, which is readily dried and reduces case hardening. Case hardening is a phenomenon observed in incompletely dried granules. In some cases, when the granules are dried at a high temperature, the inside of the granules remain wet and the surface seems dried. The granules are often hard and resist disintegration. Under compaction forces, the granules break and deform plastically to form soft tablets due to the moisture coming out of the incompletely dried granules.

The addition of Avicel PH 101 or PH 302 in wet granulation promotes rapid, even wetting as a result of the wicking action of MCC, reduced sensitivity of the wet mass to over-wetting, faster drying, fewer screen blockages or case hardenings, reduced dye migration, and faster disintegration. [6]Since MCC is water insoluble, the small drug particles get trapped between the deformed MCC particles and may delay wetting and dissolution. This must be overcome by adding portions of water soluble direct compression excipients. [4]Roller Compaction : Roller compaction is a dry process involving compaction of materials into ribbons that are then milled to generate a granulation. This granulation is then lubricated and compressed on a tablet machine. This process can be used with moisture-sensitive active pharmaceutical ingredients and is readily adaptable to continuous processing. Use of Avicel PH grades in roller compaction includes improvement of compaction in the ribbon phase, enhancement of flow of the granules, and preserving content uniformity of the final granulation.

FUNCTION

Microcrystalline cellulose, like cellulose, is a dream product for food manufacturers. Its addition to processed foods ensures uniform texture, and consistency of the product’s qualities, at many different temperatures and pH levels. It will even ensure that frozen products are delivered from freezing unaltered when thawed. Microcrystalline cellulose is also capable of emulsifying, that is, preventing the separation of oils and other ingredients that would not normally mix. Microcrystalline cellulose prevents powders from caking, stabilizes foam consistency, and makes frostings and toppings opaque for visual appeal.

Another area where cellulose is useful to food manufacturers is in adding bulk. Microcrystalline cellulose is used as a filler to increase the volume and mass of a product while reducing the use of more expensive items like flour, sugar or fat. As an added advantage, cellulose is not digested, so it does not add any calories to food. In fact, cellulose also has the ability to hold moisture, so it is used as a fat replacement; for example, it is added to prepared, diet meat products to make them juicy without fat content.

Cellulose is a natural polysaccharide (complex carbohydrate) found in all plant material. Microcrystalline cellulose consists of a specific segment of the cellulose molecule, which is chemically “snipped off” and isolated into a powder. There are several forms of microcrystalline cellulose, each performing different functions. One form is used in nutritional supplements as dietary fiber. Microcrystalline cellulose is used as an alternative to a modified cellulose, such as carboxymethyl, or hydroxypropyl cellulose.

OTHER USE AND INDUSTRIES

Microcrystalline cellulose is widely used in the pharmaceutical industry as an excipient, that is, an inert substance which binds with the active ingredient for safe delivery into the bloodstream. It prevents the medicine from being destroyed in the stomach. It may also be a filler to fill out tablets or capsules when the volume of medicine is small.

HEALTH EFFECTS

Microcrystalline cellulose is an extremely inert, natural substance, which is not digested. It passes right through our system. There are claims that taking cellulose can cleanse the colon, but the actual effects of taking it are unverified. Some claim that consuming microcrystalline cellulose can aid in weight loss, because it absorbs moisture and expands, giving a feeling of being “full”. This claim is also unproven.

ORIGINS

Microcrystalline cellulose is derived from cellulose, the indigestible part of plant material. Cellulose is a carbohydrate, which in industry is derived most commonly from wood or cotton, but may come from bamboo, or any other plant matter. To produce microcrystalline cellulose, wood pulp is treated with an acid to break up the cellulose molecules, and the desired section, the microcrystal, is isolated. It appears as a white powder.

Microcrystalline cellulose is a term for refined wood pulp and is used as a texturizer, an anti-caking agent, a fat substitute, an emulsifier, an extender, and a bulking agent in food production.[1] The most common form is used in vitamin supplements or tablets. It is also used in plaque assays for counting viruses, as an alternative to carboxymethylcellulose.[2]

In many ways, cellulose makes the ideal excipient. A naturally occurring polymer, it is composed of glucose units connected by a 1-4 beta glycosidic bond. These linear cellulose chains are bundled together as microfibril spiralled together in the walls of plant cell. Each microfibril exhibits a high degree of three-dimensional internal bonding resulting in a crystalline structure that is insoluble in water and resistant to reagents. There are, however, relatively weak segments of the microfibril with weaker internal bonding. These are called amorphous regions; some argue that they are more accurately called dislocations, because of the single-phase structure of microfibrils. The crystalline region is isolated to produce microcrystalline cellulose.