Pakistan Journal of Pharmaceutical Research

7

Authors: Mubashar Aziz1, Rakhshanda Baqai², Shahana Urooj Kazmi², Zulfiqar Ali Mirani3, Ahsan Sattar Sheikh4, Mazhar Ayaz1 ,Muhammad Hanif5, Najmul Hasan6

Bacterial biofilms are complex structured communities surrounded in a matrix of extra-cellular polymeric substances growing on rough surfaces. It is involved in multiple functions like trapping of nutrients, adherence, stability of biofilm structure and the penetration of many antibiotics.250Pus samples were collected from the depth of ulcers from each patient using Amies Transport Swabs. The specimens were inoculated on appropriate media. Biochemical characteristics of pathogens were observed by performing conventional biochemical tests and Quick Test Strips. Antibiotic resistance of isolates was checked by Kirby Bauer’s Disc Diffusion Method. Biofilm formation was initially detected by Congo Red Agar Method. Major biofilm forming isolates from different hospitals environment were Klebsiella spp., Corynebacterium spp., S. epidermidis while from hospital curtain’s samples, Shigella dysenteriae, Candida albicans and Aspergillus flavus were having capability of biofilm formation. S. aureus showed good biofilm forming ability in presence of 0.2% glucose, sucrose and lactose, P. aeruginosa showed enhancement in biofilm formation in presence of sucrose, glucose, and maltose while E. coli indicated increased biofilm formation in presence of lactose, sucrose and glucose. Most of the biofilm forming isolates were Multi drug resistant which indicate that extracellular material released by these pathogens cover the bacteria cell and hinder the antibiotic

10

Authors: Nor Hisam Zamakshshari1, Siau Hui Mah2, Gwendoline Cheng LianEe*1, Zalikha Ibrahim3, Soek Sin Teh4 and Irene See1

A series of xanthones isolated from Calophyllum depressinervosum and Calophyllum buxifolium were studied for their cytotoxicities. Ananixanthone (1), caloxanthone B (2), caloxanthone I (3), caloxanthone J (4), xanthochymone B (5), thwaitesixanthone (6),1,3,5,6-tetrahydroxyxanthone (7) and dombakinaxanthone (8) were successfully isolated from both Calophyllum species. These eight compoundsand a synthetically derived compound, thwaitesixanthone monoacetate (9) were tested for cytotoxicity activities against stomach cancer, SNU-1and LS-174T cell lines. Caloxanthone B (2) gave the highest cytotoxic activity against SNU-1 with anIC50 valueof 1.47μg/ml. Meanwhile, xanthochymone B (5) shows the highest cytotoxic activity against LS-174T cell with an IC50 value of 0.45μg/ml. The structure-activity relationship (SAR) studies predicted that the presence and arrangements of furano, pyrano and prenyl substituents in the xanthone skeleton are important towardsthe cytotoxic activity. A molecular docking simulation was performed tomodel the probable binding models of compound 2 into the HER-2(PDB ID: 3PP0) and compound 5 into β-catenin (PDB ID: 1JDH).

15

Authors: S. Ashutosh Kumar*1, Manidipa Debnath2, K. Anusha3, K. Manna1, JVLN Seshagiri Rao4, M. K. Singh1

The present investigation was undertaken to formulate and evaluate the losartan floating and bioadhesive drug delivery system using different polymers in different ratios. The main objective of the present work is to develop a novel osmotically controlled drug delivery system of losartan. It was aimed to prepare for prolonged residence in the stomach over conventional gastro retentive approaches. As the drug has short biological half-life (2 hours) hence it becomes necessary that it should be administered in 2 or 3 doses of 2.5 to 10 mg per day. Thus, the development of controlled-release dosage forms would clearly be advantageous. Formulated tablets gave satisfactory results for various evaluation parameters like tablet hardness, friability, weight variation, thickness, floating lag time, floating duration, content uniformity, ex vivo osmotically controlled strength and in vitro drug release. In all formulations Carbopol 974P is used to add osmotically controlled strength but the concentration of this polymer has significantly influenced the drug release due to its retarding property. Comparing the three different grades of Hydroxy propyl methyl cellulose (HPLC) (K4M, K15M and K100M), it was found that low-viscosity grades of HPMC K4M formulations released drug rapidly compared to K15M HPLC and K100M HPLC. Among all formulations K15M grade provided better controlled release characteristics with excellent drug release and in vitro buoyancy. From the above, it was also evident that at higher viscosity grades of polymer concentrations, the rate of drug release was retarded greatly.