Preliminary Investigation into the Use of Pleurotus Tuber-Regium Powder as a Tablet Disintegrant

PURPOSE: This investigation aims at developing a pharmaceutical excipient from local sources. Pleurotus tuber-regium powder is used locally as a soup thickener because of its ability to swell in water and add bulk to the soup. Since swelling is one of the mechanisms of action of some tablet disintegrants it was thought that the powder of P. tuber regium would be able to act as a tablet disintegrant. METHOD: The powder obtained from the mycelia of the edible giant mushroom; Pleurotus tuberregium was characterised. Its disintegrant ability in comparison with maize starch BP was investigated in paracetamol tablets prepared via the wet granulation method. RESULTS: P. tuber-regium and maize starch BP have similar true; bulk and tapped density values. The Pleurotus powder; however; showed superior flow; swelling capacity as well as waterretention capacity to maize starch BP. The swelling capacity was three times that of maize starch BP. Tablets prepared with P. tuber-regium powder disintegrated faster than those prepared with maize starch BP at concentrations below 10w/w. At the disintegrant concentration of 10 percentw/w paracetamol tablets made from both Pleurotus powder and maize starch BP had similar disintegration times and dissolution profiles. It is believed that the ability ofPleurotus powder to swell by over three times its volume in the presence of water may explain its ability to function as a tablet disintegrant. CONCLUSION: Pleurotus tuber-regium powder may therefore be used as an alternative to maize starch BP as a tablet disintegrant

Adsorptive Property of Kaolin in some Drug Formulations

PURPOSE: Kaolin is a known adsorbent; has lubricant property in powders and is therefore proposed as a lubricant in tablet formulations. This study was carried out to evaluate whether kaolin can adsorb some active drugs when mixed with them in tablet formulations even at very low concentrations. METHOD: Chloroquine and chlorpheniramine tablets were formulated with powder mixtures containing various concentrations of kaolin. The effect of kaolin on the physical properties of the tablets were examined and compared with those of standard lubricants like magnesium stearate and talc. Chloroquine and chlorpheniramine tablets and powders of amoxicillin/clavulanic acid oral powder and ampicillin/cloxacillin injection were also mixed with and without various concentrations of kaolin in water. Chemical assay of the drugs in the solutions were determined over time. RESULTS: Kaolin significantly reduced the amount of each of the drugs in the solutions containing kaolin. CONCLUSION: Kaolin reduces the amount of some drugs when incorporated in drug formulations. Therefore; its inclusion in such drug formulations should not be encouraged

Microbial Contamination and Preservative Capacity of some Brands of Cosmetic Creams

PURPOSE: Cosmetic and topical products need not be sterile but may contain low levels of microbial load during use. This study was conducted to determine and compare the level and type of microbial contaminants in commercial cosmetic products sold in the market and a laboratory prepared aqueous cream and their preservative capacities while in use. METHODS: Ten brands of commercially available cosmetic creams and lotions were randomly purchased from the open markets in Benin City. Aqueous Cream was also prepared. Their bacterial and fungal loads as well as types were evaluated. Preservative capacity was evaluated by challenging the creams and lotions with washed and characterized isolates of Staph. aureus and viable counting was performed by the surface viable method. The prepared aqueous cream was similarly challenged with the test organism. RESULTS: All the products were contaminated to varying degrees. Staphylococci and other gram-positive cocci were the most preponderant; gram-negative isolates were hardly found. Fungal contaminants consisted largely of Asp. fumigatus; Penicillium and Microsporium species. Challenge test (re-infection) with Staph. aureus revealed the commercial products as having low capacity for suppressing bacterial proliferation such as may be encountered during in -use contamination. CONCLUSION: Commercial cosmetic creams and lotions evaluated did not generally meet the standards for microbial limits as specified in official monographs. Such products can adversely affect health status of consumers as well as the stability profiles of the products

Effect of temperature changes on the densification and compression of griseofulvin and sucrose powders.

A study has been made of the effect of varying the temperature between - degree and -25 degree C on the densification and low pressure compression of griseofulvin, sucrose and mixtures of the two powders. Densification and compression of the materials were facilitated as they were cooled in the range of homologous temperatures (ratio of the experimental temperature in degree K to melting point of the material in degree K) from 0.7 to 0.5. This was attributed to a reduction in the cohesive forces operating between the particles. Values are given for the activation energies of densification and compression derived by plotting the logarithms of these properties versus the reciprocal of the absolute temperature. For both materials and their mixtures the activation energies were in the range of about 1 to 10kJ mol-1 showing that physical rather than chemical forces were operating between the particles.

Cooling as a possible method for increasing the flowability of certain pharmaceutical and other powders.

Measurements have been made of the rates of flow under gravity of powdered sugars and of fatty acids through circular orifices at temperatures between -25 and 110 degrees C. The flow rates decrease considerably as the powders are heated; conversely they increase as the powders are cooled from a high ambient temperature of 40 to -25 degrees C. The results are ascribed to changes in the cohesiveness of the powders caused by softening and plastic deformation of particles at elevated temperatures. Lactose, paracetamol and griseofulvin granule formations have been reported to show similar effects and the possibility is discussed of using cooling to increase the flowability of particular powders in pharmaceutical production. The rates of flow of the powders are given by the expression(formula: see text)where W is the flow rate in g min-1, Do is the orifice diameter in cm, rho is the particle density in g cm-3, g is the gravitational constant, and A and n are numerical terms which depend on temperature and particle size.