MULTIPARTICULATE DRUG DELIVERY SYSTEM FOR COLON TARGETING

Objective: The objective of the present investigation was to design a multi particulate delivery system for site-specific delivery of 5-aminosalicylic acid (ASA) using natural polysaccharides (pectin) and pH-sensitive polymer (Eudragit S100) for the treatment of ulcerative colitis. This system is anticipated to protect the drug loss in the upper GI tract, which results from the inherent property of Eudragit S100 (ES), and deliver ASA in the colon only.Methods: The use of enteric polymers (ES) as the protective coating on the microspheres makes them able to release the drug at the particular pH of colonic fluid. A combined mechanism of release is used, which combines specific biodegradability of polymer and pH-dependent drug release from the coated microspheres. The effects of polymer concentration, stirring rate, and concentration of emulsifier on particle size and drug loading were studied. Pectin microspheres were prepared by emulsion dehydration method using different ratios of drug and polymer (1:2 to 1:4), stirring speeds (1000-3000 rpm) and emulsifier concentrations (1%-3% wt/vol). Eudragit -coating of pectin microspheres was prepared by oil-in-oil solvent evaporation method. Both the pectin microspheres and Eudragit-coated pectin microspheres were evaluated for surface morphology, particle size and size distribution, percentage drug entrapment, swell ability and In vitro drug release in pH progression media.Result: The release profile of 5-ASA from Eudragit-coated pectin microspheres was pH dependent. Hence, the drug released quickly at pH 7.5 but the release rate was much slower in acidic medium.Conclusion: The designed drug delivery system can be used as a tool for colon targeting of drugs

ANTIBACTERIAL ACTIVITIES OF SCYTONEMA HOFMAN EXTRACTS AGAINST HUMAN PATHOGENIC BACTERIA

Objective: The present study is focused, to evaluate the effectiveness of organic solvent or aqueous extracts of Scytonema hofman against some human bacterial pathogens.Methods: The aqueous and organic solvent extracts of Scytonema hofman were analyzed for their antibacterial property against some of the human bacterial pathogens by agar well diffusion technique followed by determination MIC value.Results: The results of the present study revealed that chloroform extracts of Scytonema hofman showed a maximum inhibition zones against Escherichia coli (17.9 mm) followed by Klebsiella pneumonia (14.3 mm) and Pseudomonas aeruginosa (11.6 mm) but less effective against Staphylococcus aureus (4.8 mm). Similar result was also observed in case of ethanolic extract but having fewer inhibition zones when compared with chloroform extract. The aqueous extract was found to be insignificant along with other five organic solvent against all the tested human bacterial pathogens. The MIC values of chloroform extract were found to be 31.25 µg/ml against Escherichia coli and Pseudomonas aeruginosa, whereas in case of Klebsiella pneumonia the value was found to be 250 µg/ml.Conclusion: The chloroform extract of Scytonema hofman was found to be the most effective antibacterial property against all the tested bacterial pathogens.Â