Molecular and functional characterization of endophytic fungi from traditional medicinal plants.

This study reports the isolation of 63 endophytic fungal isolates from two traditional medicinal plants, Ocimum sanctum and Sapindus detergens from different locations of Amritsar, India. The functional characterization of the fungi for their ability to produce anti bacterial and anti cancer agent was carried out. Sixteen strains were characterized at molecular level by sequencing the amplified ITSI-5.8-ITSII region of rDNA. The phylogenetic tree resolved the endophytic fungi into different clades. The fungal endophytes belonging to order Pleosporales (Alternaria sp., Phoma sojicola and Exserohilum sp.) were functionally versatile as they produced diverse biomolecules including antibacterial agent active against Mycobacterium smegmatis, as well as cytotoxic activity against different human cancer cell lines of lung, ovary, breast, prostrate, neuroblastoma and colon.

Cytotoxic activity of 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones and 4-oxo-4H-chromene-3-carbothioic acid N-phenylamides.

6/6,7-Substituted-3-formylchromones (8a-g) were reacted with 2 equivalents thiobenzamide (9) in refluxing toluene to furnish substituted-3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones (10a-g) in high yields. Similarly, when substituted-2-anilino-3-formylchromones (8a-d) were reacted with thiobenzamide (9, 2 equivalents) in refluxing xylene, 4-oxo-4H-chromene-3-carbothioic acid N-phenylamides (11a-d) were obtained in high yields. All the compounds (10a-g) and (11a-d) display significant cytotoxic activity against a number of human cancer cell lines. Among these compounds 10e (IC(50) = 10 microM), 10b (IC(50) = 14.6 microM) and 10a (IC(50) = 10.5 microM) showed maximum cytotoxic activity on neuroblastoma. Also, the compound 10c (IC(50) = 10.5 microM) showed maximum cytotoxic activity on ovarian cancer cell line.

Cytotoxic and apoptotic activity of essential oil from Ocimumviride towards COLO 205 cells.

We investigated the apoptosis inducing effect of essential oil (EO) from aerial parts of Ocimumviride in human colorectal adenocarcinoma cells (COLO 205 cell line). The COLO 205 cells were exposed to 0.0125-0.1 microl/ml of EO for 24, 48 and 72h. Growth inhibition was determined by sulphorhodamine B (SRB) assay. Double staining with acridine orange and ethidium bromide for nuclear changes was performed. Cell cycle analysis and change in mitochondrial membrane potential was quantified by flow cytometry. Subsequently, using annexin V/PI assay, the proportion of cells actively undergoing apoptosis was determined. Changes in DNA were observed by DNA ladder assay. Eventually the surface morphology of apoptotic cells was studied by scanning electron microscopy. EO is cytotoxic to COLO 205 cells in dose and time-dependent manner, as is evident by SRB assay. This observed cell death was due to apoptosis, as established by annexin V/PI assay, DNA ladder formation and scanning electron microscopy. Our results reveal that EO has apoptosis inducing effect against COLO 205 cells in vitro and is a promising candidate for further anti-cancer study.

Cytotoxic and apoptotic activities of novel amino analogues of boswellic acids.

4-Amino analogues prepared from beta-boswellic acid and 11-keto-beta-boswellic acid, wherein the carboxyl group in ursane nucleus was replaced by an amino function via Curtius reaction, displayed improved cytotoxicity than the parent molecules. The same molecules also exhibited apoptotic activity by inducing DNA fragmentation.

Synthesis and evaluation of ethylnitrosoureas of substituted naphthalimides as anticancer compounds.

Four new ethylnitrosourea derivatives of substituted naphthalimides 3a-d have been synthesized from the respective N-(2-ethylamino) naphthalimides. Their chemical alkylating activity compared with the clinical drug CCNU and an experimental compound Mitonafide indicated that they possess lower alkylating activity than CCNU and comparable activity with the latter. Their anti-tumor efficacies were assessed in vivo in two murine ascites tumors namely Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times (MST) of drug treated (T) over untreated control (C) mice. CCNU and Mitonafide were used as positive controls for comparison. The representative compound 3a has displayed marginal anti-tumoral activity in these tumors. Three compounds were further screened in vitro in 4 different human tumor cell lines but no significant activity was observed in those lines. These compounds moderately inhibit the synthesis of DNA and RNA in S-180 tumor cells.

A tuber lectin from Arisaema jacquemontii Blume with anti-insect and anti-proliferative properties.

A tuber lectin from Arisaema jacquemontii Blume belonging to family Araceae was purified by employing a single step affinity chromatography using column of asialofetuin-linked amino activated silica beads and the bound lectin was eluted with 100 mM glycine-HCl buffer pH 2.5. The purified A. jacquemontii lectin (AJL) showed a single protein band with an apparent molecular mass of 13.4 kDa when submitted to SDS-polyacrylamide gel electrophoresis under reducing as well as non-reducing conditions. The native molecular mass of AJL determined by gel filtration on a Biogel P-200 column was 52 kDa and its carbohydrate content was estimated to be 3.40%. Thus AJL is a tetrameric glycoprotein. The purified lectin agglutinated erythrocytes from rabbit but not from human. Its activity was not inhibited by any of the mono- and disaccharides tested except N-acetyl-D-lactosamine having minimal inhibitory sugar concentration (MIC) 25 mM. Among the glycoproteins tested only asialofetuin was found to be inhibitory (MIC125 microg/mL). A single band was obtained in native PAGE at pH 4.5 while PAGE at pH 8.3 showed two bands. Isoelectric focusing of AJL gave multiple bands in the pI range of 4.6-5.5. When incorporated in artificial diet AJL significantly affected the development of Bactrocera cucurbitae (Coquillett) larvae indicating the possibility of using this lectin in a biotechnological strategy for insect management of cucurbits. Larvae fed on artificial diet containing sublethal dose of AJL showed a significant decrease in acid phosphatase and alkaline phosphatase activity while esterase activity markedly increased as compared to larvae fed on diet without lectin. Out of various human cancer cell lines employed in sulphorhodamine B (SRB) assay, this lectin was found to have appreciable inhibitory effect on the in vitro proliferation of HCT-15, HOP-62, SW-620, HT-29, IMR-32, SKOV-3, Colo-205, PC-3, HEP-2 and A-549 cancer cell lines by 82, 77, 73, 70, 41, 41, 37, 29, 21 and 21% respectively.