Assessment of antifungal activity of himalayan foliose lichens
by Priti Pandey
In vitro antifungal activity of the acetone, methanol and chloroform extracts of four lichen species viz, Bulbothirx... more In vitro antifungal activity of the acetone, methanol and chloroform extracts of four lichen species viz, Bulbothirx setschwanensis, Everniastrum nepalense, Heterodermia diademata, Parmelaria thomsonii were investigated against seven plant pathogenic fungi (Aspergillus flavus, A. fumigatus, Alternaria alternata, Fusarium oxysporum, F. solani, F. roseum and Penicillium citrinum) with reference to commercially available synthetic antifungal drug Ketoconazole (positive control). Lichen secondary metabolites were extracted using Soxhlet extractor and were further recovered through gentle evaporation of solvents in rotatory evaporator. Antifungal activity was analysed employing BauerKirby disc diffusion assay. Acetone and methanol extracts of lichenized fungi were found more effective against tested plant pathogenic fungi. Principal component analysis concluded that though, Ketoconazole was effective against four of the tested plant pathogenic fungi, acetone and methanol extracts of lichens were comparatively more effective against some broad spectrum plant pathogenic fungi (Fusarium oxysporum, F. solani, F. roseum).
Growth inhibition of Candida species and Aspergillus fumigatus by statins
FEMS Microbiology Letters (2006)
Statins are a class of drugs widely used for lowering high cholesterol levels through their action on... more Statins are a class of drugs widely used for lowering high cholesterol levels through their action on 3-hydroxy-3-methylglutaryl-CoA reductase, a key enzyme in the synthesis of cholesterol. We studied the effects of two major statins, simvastatin and atorvastatin, on five Candida species and Aspergillus fumigatus. The statins strongly inhibited the growth of all species, except Candida krusei. Supplementa- tion of Candida albicans and A. fumigatus with ergosterol or cholesterol in aerobic culture led to substantial recovery from the inhibition by statins, suggesting specificity of statins for the mevalonate synthesis pathway. Our findings suggest that the statins could have utility as antifungal agents and that fungal colonization could be affected in those on statin therapy.
Download (.pdf)Novel endoperoxides: Synthesis and activity against Candida species
Bioorganic & Medicinal Chemistry Letters (2006)
Fifteen new endoperoxides have been synthesised and tested for activity against pathogenic Candida species. These end-... more Fifteen new endoperoxides have been synthesised and tested for activity against pathogenic Candida species. These end- operoxides can be prepared in high yields, in one to three steps, from inexpensive starting materials. Despite chemical and structural similarities, their inhibitory activity against Candida growth varied greatly from one endoperoxide to another, and one species to another. This study of susceptibility to endoperoxide compounds presented here may lead to the development of potent new antifungal agents.
Design of endoperoxides with anti-Candida activity
Bioorganic and Medicinal Chemistry (2007)
Broad antifungal structure–activity relationships governing epoxy-endoperoxides 2 and 3 and their parent endoperoxides... more Broad antifungal structure–activity relationships governing epoxy-endoperoxides 2 and 3 and their parent endoperoxides 1 are reported. Their inhibitory activity against Candida albicans in conjunction with hemolytic activity and/or growth inhibition of cultured mammalian cells are reported. This information provided guidance for the further development of endoperoxide and epoxy-endoperoxides as topical antifungal agents.
Design of 1,2-dioxines with anti-Candida activity: aromatic substituted 1,2-dioxines
Tetrahedron (2008)
In an ongoing effort to rationally design new antimicrobials, 47 new 1,2-dioxines have been synthesised. Broad... more In an ongoing effort to rationally design new antimicrobials, 47 new 1,2-dioxines have been synthesised. Broad antifungal structureeactivity relationships governing aromatically substituted epoxy-1,2-dioxines 2 and 3 and their parent 1,2-dioxines 1 were assessed primarily against the pathogenic yeast, Candida albicans, with haemolytic activity of selected examples also reported.
