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Plants formed the basis of sophisticated traditional medicine systems that have been in existence for thousands of years. But, the advent of drug resistance in human pathogenic bacteria and others has prompted a search for more and better antibiotics. This has led to the identification of a new promising source of antimicrobials known as endophytes. Hence, our study was aimed to investigate the ability of endophytic fungi isolated from T. brownii to produce secondary metabolites, which can act as antimicrobial agents. In this preliminary investigation, the leaves were used for isolation of endophytic fungi and fermented, and the cell free ferment broth was subjected to antimicrobial screening against six human pathogens; Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli and Candida albicans by using standard protocol of agar well diffusion method. The results of the endophyte isolation gave three fungal isolates named TBF1, TBF2 and TBF3. According to morphological and microscopical characterizations, the isolates were found to be similar to Rhizophus oryzae (TBF1), Aspergillus niger (TBF2) and Aspergillus flavus (TBF3). Two of the three isolated endophytes i.e., TBF2 and TBF3 showed potential antimicrobial activity against S. aureus and no inhibition was found against other tested pathogens. The present study has proven that T. brownii may be a rich source of endophytic fungi with antimicrobial potential and our findings may form a basis for further studies on endophytic fungi from medicinal plants for antimicrobial activities.

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Objective: Lamivudine (LVD) is a nucleoside reverse transcriptase inhibitor originally developed as an antiretroviral drug and primarily used in the treatment of most common chronic disease of the planet, acquired immune deficiency syndrome and hepatitis B. The main objective of the study is to develop controlled drug delivery system to increase the efficacy of antiretroviral drug, LVD against human immunodeficiency virus infections. Methods:The microencapsulation of LVD in gelatin microspheres was carried out by cross-linking process with glutaraldehyde saturated toluene using ionic-gelation method. The prepared microspheres were evaluated for particle size analysis, % yield value, % drug content, drug entrapment efficiency, scanning electron microscopy for surface morphology, swelling index, accelerated stability studies, Fourier transform infrared radiation spectroscopy (FT-IR) and differential scanning calorimetry (DSC) for polymer drug compatibility, in vitro dissolution efficiency and release kinetic studies. Results:The obtained microspheres showed very smooth surface and exhibited regular spherical geometry due to higher crosslinking density. FT-IR and DSC revealed the absence of drug polymer interactions. The percentage yield, entrapment efficiency and drug content for F6 LVD microspheres was found to be 79.31%, 65.55% and 96.25% respectively. The particle size was ranged from 34.61% to 51.45 µm sizes and in vitro release profile showed that cross-linking density of gelatin microspheres effectively controlled the release of LVD. Conclusion:The findings of our investigation demonstrated that F6 of gelatin-LVD microspheres had good controlled release profile with maximum entrapment efficiency and prolonged drug release for 24 hrs or longer and this formulation would be capable of overcoming the drawbacks and limitations of LVD conventional dosage forms.