Anti-proliferative effect of fungal taxol extracted from Cladosporium oxysporum against human pathogenic bacteria and human colon cancer cell line HCT 15.

Cladosporium oxysporum a new taxol producing endophytic fungus was identified and production of taxol were characterized using UV-visible spectroscopy (UV-vis), high-performance liquid chromatography (HPLC), infrared (IR) nuclear magnetic resonance spectroscopy (NMR ((13)C and (1)H)) and liquid chromatography-mass spectrometry (LC-MS). The taxol biosynthetic gene (dbat) was evaluated for new taxol producing fungus. Antibacterial activity against six different human pathogenic bacteria was done by agar well diffusion method. The anticancer efficacy of isolated fungal taxol were also evaluated in human colon cancer cell HCT 15 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cytotoxicity and nuclear morphology analysis. The isolated fungal taxol showed positive towards biosynthetic gene (dbat) and effective against both Gram positive as well as Gram negative. The fungal taxol suppress growth of cancer cell line HCT 15 with an IC50 value of 3.5µM concentration by 24h treatment. Thus, the result reveals that C. oxysporum could be a potential alternative source for production of taxol and have antibacterial as well as anticancer properties with possible clinical applications.

Anticancer activity of fungal taxol derived from Botryodiplodia theobromae Pat., an endophytic fungus, against 7, 12 dimethyl benz(a)anthracene (DMBA)-induced mammary gland carcinogenesis in Sprague Dawley rats.

Breast cancer is the second most prevalent cancer worldwide and their incidence increases gradually. Taxol (paclitaxel), a potent anticancer drug, is naturally isolated from the bark of the Pacific yew. Taxol is widely used in the treatment of ovarian, lung and breast cancer. The increased demand for taxol, coupled with its limited availability from the protected Pacific yew, has had researchers scrambling for alternate sources. The purpose of the present study is to investigate chemopreventive effect of fungal taxol derived from a novel endophytic fungus Botryodiplodia theobromae Pat., isolated from a medicinal plant Morinda citrifolia Linn. The fungal taxol is found to be active against the 7, 12 dimethyl benz(a)anthracene (DMBA)-induced mammary gland carcinogenesis in Sprague dawley rats. The enzymic and non-enzymic antioxidants i.e. superoxide dismutase (SOD), catalase (CAT), glutatione peroxidase (GPx), glutatione-S-transferase (GST), reduced glutathione (GSH), vitamin C and vitamin E were evaluated in control and experimental groups. Lipid peroxides levels (LPO) were also tested. Histological analysis of breast tissue was analyzed by haematoxylin and eosin staining to assess the cytoprotective role of fungal taxol active against breast cancer. Immunohistochemical analyses were also performed to evaluate the effect of fungal taxol on the inflammatory marker such as Cyclooxygenase-2 (COX-2) in control and experimental groups. The results showed that the fungal taxol significantly suppresses the DMBA-induced breast cancer in Sprague dawley rats.

Bioabsorption of chromium from retan chrome liquor by cyanobacteria.

The bioaccumulation of chromium from retan chrome liquor by Spirulina fusiformis was investigated under laboratory as well as field conditions. At the optimal conditions, metal ion uptake increased with initial metal ion concentration up to 300mg/l. The effect on various physico-chemical parameters like total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), chlorides, sulphates, phenols, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) and biochemical studies related to biomass, chlorophyll-a and protein were also carried out. The present study indicates that S. fusiformis is very effective in removal of chromium (93-99%) besides removing other toxicants from retan chrome liquor. The sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and FTIR studies indicate the interaction/complexation between Cr and alga. The mechanism involved in bioaccumulation of chromium is also discussed. The process when upgraded can be applied for detoxification of tannery effluents.

Genetic subtypes of HIV type 1 in Republic of Congo.

To assess the molecular epidemiology of HIV-1 in Republic of Congo (Congo), we investigated 29 HIV-1s obtained from 82 Congolese AIDS and ARC patients in 1996 and 1997. Part of the env region including the V3 loop was phylogenetically analyzed. The genotypes observed were varied: of 29 specimens, 12 (41 %) were subtype A, 1 (3%) was subtype D, 6 (21%) were subtype G, 6 (21%) were subtype H, 2 (7%) were subtype J, and 2 (7%) could not be classified as any known subtypes (U, unclassified). The heterogeneous profile of HIV-1 infection was different from the profiles of neighboring Central African countries. These data show that subtypes G and H as well as subtype A were circulating with high prevalence. The fact that new genetic subtypes (J and U) are circulating indicates a need for a greater surveillance for these subtypes both in Congo as well as in other parts of the world.

Natural infection of chimpanzees with new lentiviruses related to HIV-1/SIVcpz.

To determine newly identified lentiviruses, termed simian immunodeficiency virus (SIV)cpz97CG4 and SIVcpz97CG6, from two wild-captured juvenile brother chimpanzees in the Republic of Congo, subgenomic pol (integrase, 288 bp), 5'tat/rev-env Cl (including vpu, 354 bp) and env (C2-C4, 544 bp) gene fragments were amplified and sequenced. The analysis revealed significantly discordant phylogenetic positions of SIVcpz97CG in each genomic region. In the trees derived from partial env sequences (V3), both SIVcpz strains clustered in human immunodeficiency virus type 1 (HIV-1) subtype A. However, in the trees derived from partial pol (integrase) and 5'tat/rev-env C1 (including vpu) sequences, they clustered independently from any of the known HIV-1 subtypes. Especially, in the 5'tat/rev-vpu tree, they branched before the root of HIV-1 group M. These findings suggest that these Congolese SIVcpz genomes are mosaic, probably due to a recombinational event in the recent past, and it provides evidence for a rather recently occurring cross-species transmission between humans and chimpanzees.