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381.
Cristiano E. Rodrigues Reis Heitor B. S. Bento Ana K. F. Carvalho Aravindan Rajendran Bo Hu 《Critical reviews in biotechnology》2019,39(4):555-570
The establishment of an efficient and feasible biorefinery model depends on, among other factors, particularly the selection of the most appropriate microorganism. Mucor circinelloides is a dimorphic fungus species able to produce a wide variety of hydrolytic enzymes, lipids prone to biodiesel production, carotenoids, ethanol, and biomass with significant nutritional value. M. circinelloides also has been selected as a model species for genetic modification by being the first filamentous oleaginous species to have its genome fully characterized, as well as being a species characterized as a potential bioremediation agent. Considering the potential of replacing several nonrenewable feedstocks is widely dependent on fossil fuels, the exploitation of microbial processes and products is a desirable solution for promoting a green and sustainable future. Here, we introduce and thoroughly describe the recent and critical applications of this remarkable fungus within the context of developing a fungal-based biorefinery. 相似文献
382.
The experimental cultivation of Kappaphycus alvarezii was done to investigate its daily growth rates and biomass yields, and their impacts on planktonic and benthos population densities were evaluated by floating raft culture method. Biomass yields and daily growth rates of K. alvarezii were observed. The phytoplankton and zooplankton densities varied from 25,250 to 319,033 cells/m3 and 12,060 to 207,893 individuals/m3, respectively. Similarly, macrobenthos and meiobenthos densities varied from 11,105 to117061 nos/m2 and 14,740 to 727,000 nos/m2, respectively. The maximum values of plankton and benthos were recorded in the control site compared with the culture sites. Pearson correlation suggests that growth rate of K. alvarezii is negatively correlated with zooplankton density (r = ?0.9); macrobenthos (r = ?0.9) and meiobenthos density (r = ?0.8) at P < 0.01 level. The crop yield negatively correlated with macrobenthos density (r = ?0.7) at P < 0.01 level and with meiobenthos density (r = ?0.6) at P < 0.05 level for the two culture sites. One- way ANOVA revealed the differences in the growth rates and crop yields. Among the two culture sites, culture site 1 showed significant variation (P < 0.01), whereas culture site 2 showed statistically insignificant (P > 0.01). The conclusion suggests that water nutrient declined at both culture sites than control site. So, the plankton and benthic fauna were declined in the culture sites. 相似文献
383.
Kannan Karuppiah Kannapiran Ethiraj Kodeeswaran Paramasivam Kumar Rajendran Madhuri Krishnamoorthy Divya Dharmaraj 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):860-862
This study deals with the length-weight relationships (LWRs) of three commercially important marine fishes belonging to the family Clupeidae from the major landing centers in Tuticorin, Mandapam, Thondi, Nagapattinam and Chennai in southeast coast of India. Monthly sampling were done at the respected landing centers from June, 2018 to April, 2019 from the commercial trawlers (with cod-end mesh size of 25–35 mm) and gill netters (with different mesh size vary from 20 to 170 mm). The estimated ‘b’ values ranged from 3.1215 (Sardinella albella) to 3.1819 (Amblygaster clupeoides) and ‘a’ values varied from 0.0059 (A. clupeoides) to 0.0074 (S. albella). The study also provides a new maximum total length (TLmax) for two species A. clupeoides and Sardinella fimbriata. 相似文献
384.
Dhiman Das Kathyayini Sivasubramanian Praveenbalaji Rajendran Manojit Pramanik 《Journal of biophotonics》2021,14(3):e202000371
Deep vein thrombosis (DVT) is a disorder when a blood clot (thrombus) is formed in one of the deep veins. These clots detach from the original sites and circulate in the blood stream at high velocities. Diagnosing these blood clots at an early stage is necessary to decide the treatment strategy. For label-free, in vivo, and real-time detection, high framerate photoacoustic imaging can be used. In this work, a dual modal clinical ultrasound and photoacoustic (PA) system is used for the high framerate PA imaging of circulating blood clots in blood at linear velocities up to 107 cm/sec. Blood clot had 1.4 times higher signal-to-noise ratio (SNR) in the static mode and 1.3 times higher SNR compared to blood PA signal in the flow experiments. This work demonstrates that fast-moving circulating blood clots are easy to recognize against the background PA signal and may aid in early diagnosis. 相似文献
385.
Cytoplasmic oestradiol receptors have been reported in breast tumor tissue but not in the uninvolved tissue from the same patients. Since gynaecomastic tissue is highly predisposed to neoplastic transformation, such receptors were looked for in this tissue from 13 phenotypic males of whom 6 had Klinefelter's syndrome. High affinity saturable binding (Kd approximately 10(-10) M) of 3H-oestradiol-17 beta was found in the breast tissue from 12 of these patients by gel elution and dextran-coated charcoal techniques. The concentration of binding sites were found to range from 16 to 359 fmol/mg cytosol protein. Previous studies by the present authors showing steroid aromatising capacity and the present finding of specific oestradiol receptors in a 'high-risk tissue' in the absence of any histologically detectable neoplasms might be relevant in elucidating the natural history of breast cancer in such individuals. 相似文献
386.
To understand the structure-function relationship of the enzyme lipase the effect of acid pH on the activity of lipase has been followed using a number of physico-chemical techniques. Lipase from wheat/germ has S20,w value of 2.2 S and a molecular weight of 42,000 +/- 1,000. The enzyme has an intrinsic viscosity of 4.72 ml/g indicating it to be elongated in shape. With decrease in pH below 7.0 microenvironmental changes occur in the neighborhood of active site accompanied by minor conformational changes without any gross change in the hydrodynamic properties of the protein, as monitored with ultraviolet difference spectra, fluorescence spectra, viscosity and circular dichroism. The kinetics of the inactivation process has been established as consisting of a fast step and a slow step with a k value of 73/sec and 7.2/sec respectively. At extreme acid pH the enzyme reaggregates to a polymer arising out of hydrophobic interaction and the polymer has no activity. 相似文献
387.
388.
The role of hydrophobic force in biological function through the formation of several local macro-molecular structures is evident.
Carbon is the element that contributes to biological function in living systems. We show that carbon distribution is related to
protein activity using an example. The carbon distribution profile is foreseen to help undestand unfolded and misfolded regions of
protein structures. The carbon distribution profile in a toxin protein that is found associated with the toxic shock syndrome is
described in this study. The carbon profile provides insight to the association of specific residues responsible for toxicity. 相似文献
389.
390.
In a culture of Alocasia indica (2n=28), one plant was found to be desynaptic. At pachytene, pairing apparently was complete, but at diakinesis and metaphase I on the average only 2.36 and 1.53 bivalents respectively were found. Desynapsis is of the medium-strong type according to Prakken. Later meiotic stages were irregular and pollen sterility was 95%. The origin must have been spontaneous mutation. 相似文献