Optimization of culture conditions for enhanced production of extracellular α-amylase using solid-state and submerged fermentation from Aspergillus tamarii MTCC5152.

Amylases are one of the main enzymes used in various industries such as food, fermentation, textile, and pharmaceuticals. Microorganisms are the potent sources of amylase enzyme, apart from plant and animal sources. Fungal amylases are more stable than bacterial amylases. The production of extracellular α-amylase from Aspergillus tamarii MTCC5152 using solid-state and submerged fermentation (SSF and SmF) and the various nutritional factors influencing its production were studied. A higher activity of α-amylase (519.40 u/g) was attained in a medium having wheat bran (WB) alone as the substrate at an initial moisture content of 70% (v/w) with 2.5% (v/w) of inoculum level (containing 106 spores/ml) after 4 days of incubation at 28°C by SSF. Addition of 1% glucose to WB containing basal medium enhanced α-amylase production (6.49 u/ml) after 4 days of incubation by SmF method. Comparative evaluation of enzyme production by SSF and SmF methods produced better results in SSF method.

Synthesis of ecofriendly copper oxide nanoparticles for fabrication over textile fabrics: Characterization of antibacterial activity and dye degradation potential.

Growing concerns over the toxicity of metallic nanoparticles synthesized using physical and chemical techniques seems to be a major hurdle for researchers. Green synthesis of nanoparticles is one of the promising, ecofriendly and safer methods. Utilizing plant sources as reducing agents will replace the use of toxic chemicals for nanoparticle synthesis. Among the various nanoparticles, copper has been theoretically and practically proved for its antimicrobial properties. However, to reduce the risk of copper toxicity, Ruellia tuberosa (R. tuberosa) aqueous extract is used for the synthesis of CuONPs in the present study. Nonetheless, till date no work has been reported on the use of R. tuberosa aqueous extract for the synthesis of CuONPs. In the present study, aqueous extract of R. tuberosa has been used for the synthesis of CuONPs. The synthesis of CuONPs was confirmed by the absorption peak at 327 nm representing the nanorods with an average size of 83.23 nm. Further, the CuONPs revealed antimicrobial effects against clinical pathogens such as Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Embedding CuONPs on cotton fabrics showed bactericidal activity against the bacterial pathogens. In addition, the photocatalytic property of the CuONPs was divulged by their crystal violet (CV) dye degradation potential. Thus, the green synthesized CuONPs using R. tuberosa could provide a remedy against bacterial pathogens in hospital and industrial environments.

6-Nitro-2-(3-hydroxypropyl)-1H-benz[de]isoquinoline-1,3-dione, a potent antitumor agent, induces cell cycle arrest and apoptosis.

BACKGROUND: Anticancer activities of several substituted naphthalimides (1H-benz[de]isoquinoline-1,3-diones) are well documented. Some of them have undergone Phase I-II clinical trials. Presently a series of ten N-(hydroxyalkyl) naphthalimides (compounds 1a-j) were evaluated as antitumor agents. METHODS: Compounds 1a-j were initially screened in MOLT-4, HL-60 and U-937 human tumor cell lines and results were compared with established clinical drugs. Cytotoxicities of compounds 1d and 1i were further evaluated in a battery of human tumor cell lines and in normal human peripheral blood mononuclear cells. Cell cycle analysis of compound 1i treated MOLT-4 cells was studied by flow cytometry. Its apoptosis inducing effect was carried out in MOLT-4 and HL-60 cells by flow cytometry using annexin V-FITC/PI double staining method. The activities of caspase-3 and caspase-6 in MOLT-4 cells following incubation with compound 1i were measured at different time intervals. Morphology of the MOLT-4 cells after treatment with 1i was examined under light microscope and transmission electron microscope. 3H-Thymidine and 3H-uridine incorporation in S-180 cells in vitro following treatment with 8 µM concentration of compounds 1d and 1i were studied. RESULTS: 6-Nitro-2-(3-hydroxypropyl)-1H-benz[de]isoquinoline-1,3-dione (compound 1i), has exhibited maximum activity as it induced significant cytotoxicity in 8 out of 13 cell lines employed. Interestingly it did not show any cytotoxicity against human PBMC (IC50 value 273 µM). Cell cycle analysis of compound 1i treated MOLT-4 cells demonstrated rise in sub-G1 fraction and concomitant accumulation of cells in S and G2/M phases, indicating up-regulation of apoptosis along with mitotic arrest and/or delay in exit of daughter cells from mitotic cycle respectively. Its apoptosis inducing effect was confirmed in flow cytometric study in MOLT-4 and the action was mediated by activation of both caspase 3 and 6. Light and transmission electron microscopic studies corroborated its apoptosis inducing efficacy at a concentration of 10 µM in MOLT-4 cells. Its apoptosis induction was also observed in HL-60 cells to an extent much greater than well known apoptosis inducing agents as camptothecin and cis-platin at 10 µM concentration each. It significantly inhibited DNA and RNA synthesis in S-180. CONCLUSIONS: In essence, compound 1i showed potential as an antitumor agent.