Joveeta Joseph

Microsporidial Keratitis: Need for Increased Awareness

Since the devastation of the European silk worm industry in the 19th century, microsporidia have been recognized as important organisms. An enormous literature is available on their biology, phylogeny, classification, disease profile, diagnosis, and treatment; however, it is only recently that ophthalmologists have begun to take note of these organisms. The last two decades have seen several publications related to ocular microsporidiosis, in particular those forms affecting the cornea. Both immunocompetent and immunocompromised patients are at risk of developing corneal infections that may range from self limiting mild keratoconjunctivitis to severe stromal keratitis recalcitrant to medical treatment. Exposure to soil, muddy water, and minor trauma are possible risk factors. Although reliable prevalence data are lacking, recent studies indicate a high prevalence of microsporidial keratoconjunctivitis in the rainy season, especially in India and other countries with similar climates. For instance, a high prevalence has been documented in Singapore. We bring together the information available on ocular microsporidiosis.

Physicochemical characterization and antioxidant activity of melanin from a novel strain of Aspergillus bridgeri ICTF-201

Aims:u2002 The aim of the study is to isolate and characterize a melanin pigment from a new strain of Aspergillus bridgeri isolated from rhizosphere soil of Eucalyptus tree and to investigate its antioxidant activity.

Synthesis, biological evaluation, and molecular modeling of (E)-2-aryl-5-styryl-1,3,4-oxadiazole derivatives as acetylcholine esterase inhibitors

AbstractnA library of 2,5-disubstituted 1,3,4-oxadiazole derivatives of (E)-2-aryl-5-(3,4,5-trimethoxystyryl)-1,3,4-oxadiazoles 4(a–o) and (E)-2-aryl-5-(2-benzo[d][1,3]dioxol-5-yl)vinyl)-1,3,4-oxadiazoles 5(a–q) were synthesized and evaluated for their in vitro acetylcholinesterase (AChE) inhibitory activity. All the synthesized compounds exhibited moderate to good inhibitory activity toward the AChE enzyme. Among the oxadiazole derivatives examined, compounds 4a, 4g, 5c, and 5m (IC50 values of 24.89, 13.72, 37.65, and 19.63xa0μM, respectively) were found to be promising inhibitors of AChE. Molecular protein–ligand docking studies were examined for these compounds using GOLD docking software and their binding conformations were determined and the simultaneous interactions mode was also established for the potent derivatives.

Metabolite profiling and biological activities of bioactive compounds produced by Chrysosporium lobatum strain BK-3 isolated from Kaziranga National Park, Assam, India

In an ongoing survey for bioactive potential of microorganisms from different biosphere zones of India, a new Chrysosporium lobatum strain BK-3 was isolated from soil sample collected from a biodiversity hotspot, Kaziranga National Park, Assam, India. Bioactivity-guided purification resulted in the isolation of two bioactive compounds whose chemical structures were elucidated by 1H and 13C Nuclear Magnetic Resonance (NMR), 2D-NMR, Fourier Transform Infra-red (FT-IR) and mass spectroscopic techniques, and were identified as α, β-dehydrocurvularin and curvularin. Only curvularin exhibited 80% acetylcholinesterase (AChE) inhibitory activity. Detailed ligand receptor binding interactions were studied for curvularin by molecular docking studies. Further, both curvularin and α, β-dehydrocurvularin had similar level of cytotoxicity against different human tumour cell lines like A549, HeLa, MDA-MB-231 and MCF-7, while α, β-dehydrocurvularin was active against COLO 205 with a IC50 of 7.9xa0μM, but curvularin was inactive. α, β-Dehydrocurvularin also showed good superoxide anion scavenging activity with an EC50 value of 16.71xa0μgxa0ml-1. Hence, both these compounds exhibited differences in bioactive profiles and this was probably associated with their minor structural differences. This is a first report on bioactive compounds exhibiting AChE inhibitory, cytotoxicity and antioxidant activities from Chrysosporium lobatum strain BK-3.