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371.
372.
Low concentrations of metals of the first row transition series, Zn2+, Co2+, Mn2+, Ni2+, Cu2+ and Fe2+, and to a lesser extent the group IIa ions, particularly Mg2+, influenced the interaction of firefly luciferase [Photinus luciferin:oxygen 4-oxidoreductase (decarboxylating, ATP-hydrolysing), EC 1.13.12.7] with a number of triazine dyes. For example Cu2+ promoted the binding of luciferase to Cibacron Brilliant Blue (BR-II) and Cibacron Blue F3GA a dichloro and monochloro triazine dye, respectively. On the other hand Zn2+ prevented dye inactivation and even enhanced the enzyme activity. Specificity was observed in the interference of different metals interacting with different dye-protein. This is made use of in triazine dye affinity chromatography. 相似文献
373.
Shankar Vijayalakshmi Marimuthu Govindarajan Norah Al-Mulahim Zubair Ahmed Shahid Mahboob 《Saudi Journal of Biological Sciences》2021,28(1):901
This study presents ethanol''s fabrication by fermenting the golden trumpet flower (Allamanda schottii L) with the yeast strain Saccharomyces cerevisiae. The changes in different parameters during fermentation were studied and optimized while producing the ethanol and the end product was subjected to emission test study by blending petrol and ethanol. The Allamanda floral substrate contains 65% polysaccharides. The strain S. cerevisiae was obtained in the form of baker’s yeast from a domestic shop. For 100 ml of slurry, the highest bioethanol yield recorded was about 18.75 ml via optimization of different culture conditions, including a 1:8 ratio for slurry preparation, maintained under 35 ⁰C, 5.5 pH, 72 h. old inoculum with a quantity of 3.75 g 100 ml−1, fermented for120 h. The highest yield of bioethanol was acquired under the addition of urea. This technique & design is capable of industrial-scale fabrication of bioethanol by using A. schottii floral substrates. This research was conducted to fabricate ethanol by fermentation (A. schottii L) floral substrate with S. cerevisiae. The optimum physiochemical parameters required to obtain the highest yield of bioethanol from A. schottii flower by fermentation was studied. The immobilization strategy with a cheap agricultural substrate and magnetic nanoparticles were also studied. The engine performance and emission studies were done with different blends of petrol and bio-ethanol. 相似文献
374.
A. Kavitha P. Prabhakar M. Vijayalakshmi Y. Venkateswarlu 《Letters in applied microbiology》2009,49(4):484-490
Aims: To isolate and identify the bioactive compounds produced by Nocardia levis MK‐VL_113. Methods and Results: Cultural characteristics of Noc. levis isolated from laterite soils of Guntur region were recorded on International Streptomyces Project media. Morphological studies of the strain through scanning electron microscopy revealed the clear pattern of its hyphal fragmentation into rod‐shaped bacilli. Chemical examination of the secondary metabolites of the strain grown on sucrose–tryptone broth led to the isolation of three fractions active against Bacillus cereus. Further analysis of second fraction resulted in the isolation of two active subfractions. Two different phthalate esters, namely, bis‐(2‐ethylhexyl) phthalate and bis‐(5‐ethylheptyl) phthalate, were purified from the first active subfraction, and the structural elucidation of these compounds was confirmed on the basis of FT‐IR, mass and NMR spectroscopy. The partially purified second subfraction subjected to Gas Chromatography–Mass spectroscopy contained nine components: decanedioic acid; 2,6‐piperdione monooxime; 1‐eicosanol; beta‐1‐arabinopyranoside, methyl; cyclopentaneundecanoic acid; hexadecanoic acid; silane, trichloro eicosyl; 1‐hexacosanol; and 1,2‐dodecanediol. The antimicrobial activity of the bioactive compounds produced by Noc. levis was expressed in terms of minimum inhibitory concentration. Conclusions: The present study clearly revealed that the metabolites of Noc. levis act as bioactive compounds against Gram‐positive and Gram‐negative bacteria, yeast and filamentous fungi. It also supports the idea that there are a number of rare actinomycetes remained to be explored for new bioactive compounds. Significance and Impact of the Study: Metabolites of Noc. levis exhibited antibacterial and antifungal activities. This is the first report of bis‐(5‐ethylheptyl) phthalate as well as the nine partially purified compounds from actinomycetes. In addition, this is also the first report of bis‐(2‐ethylhexyl) phthalate from the genus Nocardia. 相似文献