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Pyritic sulphur was removed from coal by growing Thiobacillus ferrooxidans in a 250 ml batch bioreactor. Thiobacillus ferrooxidansgrown on sulphur and which was added 5 days after initial inoculation, enhanced the iron solubilization rate by 35% as compared to control (without addition of sulphur-grown cells). About 93% pyritic sulphur was removed in presence of sulphur-grown cells as compared to 77% in the control.  相似文献   
323.
Summary Characterization of sinefungin related antifungal antibiotics from fermentation broth was accomplished by coupling photodiode array (PDA) detection to high performance liquid chromatography (HPLC). From the combined HPLC-PDA evaluation of broth filtrate, we detected five sinefungin related components. Fast atom bombardment (FAB) mass spectroscopic evaluations, mass-analysed ion kinetic energy spectra (MIKES) and collision activated (CA) MIKES of these components confirmed their respective identities. Our findings from the combination of HPLC photodiode array acquisition and FAB-mass spectrometry suggest we have detected the presence of a previously unreported sinefungin analogue.  相似文献   
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End-group mediated conjugation of bacterial polysaccharides (PSs) to carrier proteins containing T-helper cell epitopes renders such polysaccharides immunogenic also in young infants. Optimal construction of such conjugate vaccines requires fragmentation of the PS prior to the coupling reaction. In the present study a general simple and inexpensive method for the fragmentation of PSs is presented. It is based on the irradiation of isolated PSs in an electron beam accelerator. Exposure of isolated pneumococcal capsular polysaccharides (PnPSs) to ionizing radiation resulted in their partial depolymerization in a radiation dose-dependent manner. Radiation, unlike sonication, generated PnPS fragments of molecular size lower than 50 kDa and as small as 1.5 kDa when high radiation doses were used. These PnPS fragments have terminal reducing groups that can be easily used for chemical activation and subsequent coupling to any chosen carrier protein. The radiation-produced PnPS fragments retained their antigenic epitopes, when compared to native, full-size PnPSs as determined by enzyme-linked immunoassay.  相似文献   
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The genetic characteristic such as ‘fermentability’ of a tea cultivar could be utilised to obtain maximum colour/bloom during manufacture of black tea. Pigment profile analysis has been used as a tool to assess the characteristic of a black tea brew. Fine plucking and optimum processing conditions are two basic requirements in producing good quality black tea. The assamica variety is characterised by linalool content while geraniol is specific in chinary clones. The higher amounts of terpenoids improved the flavour characteristic of second flush tea of north east India in general and Darjeeling in particular. Further, the surplus fatty acid degradation products lower the quality of black tea during monsoon flush. Presented at the 3rd National Symphosium on Bioorganic Chemistry, 1987, Hyderabad.  相似文献   
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