BIOLOGICAL ACTIVITIES OF ALTERNARIA SP. RL4 – A POTENT ENDOPHYTIC FUNGUS ASSOCIATED WITH RAUVOLFIA SERPENTINA L. BENTH.

Objectives: Endophytic fungi are considered as an important source of bioactive metabolites. The present study focused on the isolation of potent endophytic fungal strains from well-known medicinal plant Rauvolfia serpentina L. Benth. having biological activities.Materials & Methods: Fungal endophytes were isolated from aerial parts of the plant and the potent strain was selected on the basis of antibacterial activities of cell-free supernatant (CFS). Ethyl acetate (EA) extraction of CFS was done and mode of action of EA fraction was checked against pathogenic bacteria. EA fraction was also analyzed by thin-layer chromatography (TLC). In addition, antioxidant activity was checked by 1,1-Diphenyl- 2-picrylhydrazyl-free radical scavenging assay and anticancer activity was checked against breast cancer cell line MCF-7 by MTT assay.Results: Among the different endophytic fungal isolates, CFS of Alternaria sp. RL4 produced prominent zones of inhibition against numbers of Gram-positive pathogenic bacteria including Staphylococcus aureus (12±0.5 mm) and Listeria monocytogenes (17±2.0 mm). Massive reductions in bacterial CFS were noticed upon treatment with EA fraction (2 mg/ml). It also showed strong cidal mode of action against Gram-positive organisms. TLC analysis revealed the production of two different compounds with antibacterial potentials. In addition, EA fraction of RL4 showed very good antioxidant property with an IC50 value of 49.80±2.11μg/ml. MTT assay also suggested the anticancerous properties of EA fraction of RL4.Conclusion: Alternaria sp. RL4 could be a very good source of bioactive compounds for the development of new drugs

A study of photoionized gas in two HII regions of the N44 complex in the LMC using MUSE observations

We use the optical integral field observations with Multi-Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope, together with CLOUDY photoionization models to study ionization structure and physical conditions of two luminous HII regions in N44 star-forming complex of the Large Magellanic Cloud. The spectral maps of various emission lines reveal a stratified ionization geometry in N44 D1. The spatial distribution of [O I] 6300A emission in N44 D1 indicates a partially covered ionization front at the outer boundary of the H II region. These observations reveal that N44 D1 is a Blister HII region. The [O I] 6300A emission in N44 C does not provide a well-defined ionization front at the boundary, while patches of [S II] 6717 A and [O I] 6300A emission bars are found in the interior. The results of spatially resolved MUSE spectra are tested with the photoionization models for the first time in these HII regions. A spherically symmetric ionization-bounded model with a partial covering factor, which is appropriate for a Blister HII region can well reproduce the observed geometry and most of the diagnostic line ratios in N44 D1. Similarly, in N44 C we apply a low density and optically thin model based on the observational signatures. Our modeling results show that the ionization structure and physical conditions of N44 D1 are mainly determined by the radiation from an O5 V star. However, local X-rays, possibly from supernovae or stellar wind, play a key role. In N44 C, the main contribution is from three ionizing stars.Comment: Accepted for publication in Ap

Modified Karatsuba multiplier for key equation solver in RS code

Finite field arithmetics are often used in linear block codes such as BCH and Reed–Solomon codes and also in cryptographic algorithms. Finite field multipliers play an important role and consume a significant amount of area in VLSI design. This paper presents an improved generalized Karatsuba multiplier. Optimization of the Karatsuba multiplication algorithm can be done by splitting the product terms into two alternative forms and expressing all the terms in the repeated fashion. We have compared the hardware requirement of our proposed multiplier with the original Karatsuba multiplier. The proposed multiplier requires lesser number of additions compared to original Karatsuba multiplier and the overall area is reduced by 53.75% (without reduction) and 52.08% (with reduction). The proposed multiplier is also faster than the original Karatsuba multiplier by 3.63% (without reduction) and 3.91% (with reduction). The proposed modified Karatsuba multiplier is also applied to compute key equation in RS(47, 41) decoder which is applied in intelligent home networking. All the simulation works were done using Xilin14.3 ISE simulator and the multipliers were implemented in Vertex 5 FPGA device family

Anti-bacterial activity of <i style="mso-bidi-font-style:normal">Achatina</i> CRP and its mechanism of action

692-704The physiological role of C-reactive protein (CRP), the classical acute-phase protein, is not well documented, despite many reports on biological effects of CRP in vitro and in model systems in vivo. It has been suggested that CRP protects mice against lethal toxicity of bacterial infections by implementing immunological responses. In Achatina fulica CRP is a constitutive multifunctional protein in haemolymph and considered responsible for their survival in the environment for millions of years. The efficacy of Achatina CRP (ACRP) was tested against both Salmonella typhimurium and Bacillus subtilis infections in mice where endogenous CRP level is negligible even after inflammatory stimulus. Further, growth curves of the bacteria revealed that ACRP (50 µg/mL) is bacteriostatic against gram negative salmonellae and bactericidal against gram positive bacilli. ACRP induced energy crises in bacterial cells, inhibited key carbohydrate metabolic enzymes such as phosphofructokinase in glycolysis, isocitrate dehydrogenase in TCA cycle, isocitrate lyase in glyoxylate cycle and fructose-1,6-bisphosphatase in gluconeogenesis. ACRP disturbed the homeostasis of cellular redox potential as well as reduced glutathione status, which is accompanied by an enhanced rate of lipid peroxidation. Annexin V-Cy3/CFDA dual staining clearly showed ACRP induced apoptosis-like death in bacterial cell population. Moreover, immunoblot analyses also indicated apoptosis-like death in ACRP treated bacterial cells, where activation of poly (ADP-ribose) polymerase-1 (PARP) and caspase-3 was noteworthy. It is concluded that metabolic impairment by ACRP in bacterial cells is primarily due to generation of reactive oxygen species and ACRP induced anti-bacterial effect is mediated by metabolic impairment leading to apoptosis-like death in bacterial cells. </span

An x-ray absorption spectroscopy study of Ni–Mn–Ga shape memory alloys

The austenite to martensite phase transition in Ni–Mn–Ga ferromagnetic shape memory alloys was studied by extended x-ray absorption fine structure (EXAFS) and x-ray absorption near-edge structure (XANES) spectroscopy. The spectra at all the three elements', namely, Mn, Ga and Ni, K-edges in several Ni–Mn–Ga samples (with both Ni and Mn excess) were analyzed at room temperature and low temperatures. The EXAFS analysis suggested a displacement of Mn and Ga atoms in opposite direction with respect to the Ni atoms when the compound transforms from the austenite phase to the martensite phase. The first coordination distances around the Mn and Ga atoms remained undisturbed on transition, while the second and subsequent shells showed dramatic changes indicating the presence of a modulated structure. The Mn rich compounds showed the presence of antisite disorder of Mn and Ga. The XANES results showed remarkable changes in the unoccupied partial density of states corresponding to Mn and Ni, while the electronic structure of Ga remained unperturbed across the martensite transition. The post-edge features in the Mn K-edge XANES spectra changed from a double peak like structure to a flat peak like structure upon phase transition. The study establishes strong correlation between the crystal structure and the unoccupied electronic structure in these shape memory alloys

HPLC chromatogram of isolated antifungal compounds from culture broth of <i>L</i>. <i>fermentum</i> C14.

<p>HPLC chromatogram of isolated antifungal compounds from culture broth of <i>L</i>. <i>fermentum</i> C14.</p

Control of spoilage of bread samples using <i>L</i>. <i>fermentum</i> C14; treated with C14 cell suspension (5.8 × 10⁷ CFU/ml) (A), treated with <i>Mucor</i> sp. spores (3.7 × 10⁴ spores/ml) (B), treated with <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores /ml) (C), treated with C14 cell suspension (5.8 × 10⁷ CFU /ml) as well as <i>Mucor</i> sp. spores (3.7 × 10⁴ spores /ml) (D), treated with <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores /ml) (E), treated with C14 cell suspension (5.8 × 10⁷ CFU /ml) as well as <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores / ml) (F), untreated (G).

<p>Control of spoilage of bread samples using <i>L</i>. <i>fermentum</i> C14; treated with C14 cell suspension (5.8 × 10⁷ CFU/ml) (A), treated with <i>Mucor</i> sp. spores (3.7 × 10⁴ spores/ml) (B), treated with <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores /ml) (C), treated with C14 cell suspension (5.8 × 10⁷ CFU /ml) as well as <i>Mucor</i> sp. spores (3.7 × 10⁴ spores /ml) (D), treated with <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores /ml) (E), treated with C14 cell suspension (5.8 × 10⁷ CFU /ml) as well as <i>B</i>. <i>subtilis</i> (4.6 × 10⁴ spores / ml) (F), untreated (G).</p