Departments View all
Recent Publications View all
- SourceAvailable from: S. M. Abu Sayem[Show abstract] [Hide abstract]
ABSTRACT: Amylases are one of the most important enzymes in present-day biotechnology. The present study was concerned with the production and partial characterization of extracellular amylase from Bacillus amyloliquefaciens P-001. The effect of various fermentation conditions on amylase production through shake-flask culture was investigated. Enzyme production was induced by a variety of starchy substrate but corn flour was found to be a suitable natural source for maximum production. Tryptone and ammonium nitrate (0.2%) as nitrogen sources gave higher yield compared to other nitrogen sources. Maximum enzyme production was obtained after 48 hrs of incubation in a fermentation medium with initial pH 9.0 at 42°C under continuous agitation at 150 rpm. The size of inoculum was also optimized which was found to be 1% (v/v). Enzyme production was 2.43 times higher after optimizing the production conditions as compared to the basal media. Studies on crude amylase revealed that optimum pH, temperature and reaction time of enzyme activity was 6.5, 60°C and 40 minutes respectively. About 73% of the activity retained after heating the crude enzyme solution at 50°C for 30 min. The enzyme was activated by Ca(2+) (relative activity 146.25%). It was strongly inhibited by Mn(2+), Zn(2+) and Cu(2+), but less affected by Mg(2+) and Fe(2+).
- [Show abstract] [Hide abstract]
ABSTRACT: Electronic and optical properties of Silicon Nanowire (SiNW) obtained from theoretical studies and experimental approaches have been reviewed. The diameter dependency of bandgap and effective mass of SiNW for various terminations have been presented. Optical absorption of SiNW and nanocone has been compared for different angle of incidences. SiNW shows greater absorption with large range of wavelength and higher range of angle of incidence. Reflectance of SiNW is less than 5% over majority of the spectrum from the UV to near IR region. Thereafter, a brief description of the different growth techniques of SiNW is given. The advantages and disadvantages of the different catalyst materials for SiNW growth are discussed at length. Furthermore, three thermodynamic aspects of SiNW growth via the vapor-liquid-solid mechanism are presented and discussed.
- [Show abstract] [Hide abstract]
ABSTRACT: A novel ligand (E)-2-styryl-1H-imidazo [4, 5-f] [1, 10] phenanthroline(L) has been synthesized from 1,10-phenanthroline-5,6-dione. Its transition metal complexes, [FeLCl4][L-H] and [CuL2](NO3)2 have also been synthesized. Besides, three mixed ligand lanthanide metal complexes of Phendione and β-diketones have been synthesized, namely [Eu(TFN)3(Phendione)] (TFN=4,4,4-trifluoro-1(2-napthyl)-1,3-butanedione), [Eu(HFT)3(Phendione)] (HFT=4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)-1,3-hexanedione), [Yb(HFA)3(Phendione)] (hfa=hexafluoroacetylacetonate). The synthesized ligands and metal complexes have been characterized by FTIR, UV-Visible spectroscopy and PL spectra. DNA binding activities of the complexes and the ligands have been studied by DNA gel electrophoresis. DNA binding studies showed that Fe complex of the synthesized ligand is more potent DNA binding and damaging agent compare to others under study. The synthesized compounds were also screened for their antimicrobial activities by disc diffusion method against three microbes, namely Escherichia coli, Staphylococcus aureus, Proteus penneri. The lanthanide complexes of phendione showed great antibacterial activities.
Information provided on this web page is aggregated encyclopedic and bibliographical information relating to the named institution. Information provided is not approved by the institution itself. The institution’s logo (and/or other graphical identification, such as a coat of arms) is used only to identify the institution in a nominal way. Under certain jurisdictions it may be property of the institution.
Rg score distribution
No data available.