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Summary A simple new technique has been developed to greatly increase the yield of protoplasts from plant organs without injury to the plant. Mechanical perturbation (MP) by non-stressful rubbing of oat leaf segments and bean internodes yielded ten to twenty times more viable protoplasts than did controls. The increase in protoplast yield due to MP is best manifested, if the organs are excised and transferred to the cellulytic enzymes immediately after MP is given to the intact organ. The enzymes begin digesting from the lower end of the bean internodes and proceed acropetally. Vacuum infiltration of control oat leaf segments for 15 min with enzyme solution resulted in increased yield but less than due to MP. Increased levels of calcium (10 mM) in the medium decreased the yield of protoplasts from both control and MP-treated plant organs. EGTA significantly increased the yield of protoplasts from control oat leaf segments and marginally over that found in the control bean internodes. Cycloheximide increased the yield of protoplasts from oat leaf segments but not from bean internodes. It is suggested that MP may increase the susceptibility of cell wall polymers to cellulytic enzymes by reducing calcium cross linking. MP is thus a tool for increasing the yield of protoplasts from plant organs without causing injury.Abbreviations CHI
cycloheximide
- EGTA
ethyleneglycol-bis-(ß-aminoethyl ether)-N,N-tetraacetic acid
- FDA
fluorescein diacetate
- MP
mechanical perturbation 相似文献
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The effect of micromixing and macromixing on enzyme reaction of Michaelis-Menten type in a real continuously stirred tank reactor (CSTR) is considered. The effect of bypassing of a fraction of feed stream, dead space, initial enzyme concentration and Michaelis-Menten constant on substrate conversion is evaluated. Bypass reduces the substrate conversion significantly compared with other parameters in the case of micro and macromixing. Micromixing predicts higher substrate conversions compared with macromixing. The effect of micro and macromixing on substrate conversion is negligible at low and high conversions.List of Symbols C kmol/m3
concentration of reactant
- ¯C kmol/m3
average concentration of reactant
- CA kmol/m3
exit concentration of reactant A
- CAa kmol/m3
exit concentration of reactant A from active zone
- CAO kmol/m3
initial concentration of reactant A
- CEO kmol/m3
initial enzyme concentration
- CO kmol/m3
initial concentration of reactant
- E(t) 1/s
exit age distribution function
- k 1/s
reaction rate constant
- M kmol/m3
Michaelis-Menten constant
- r kmol/(m3s)
rate of reaction
- –rA kmol/(m3s)
rate of reaction with respect to A
- t s
time
- v m3/s
volumetric feed rate
- va m3/s
volumetric feed rate entering the active zone
- vb m3/s
volumetric feed rate entering the bypass stream
- V m3
total volume of the vessel
- Va m3
active volume of the vessel
- Vd m3
volume of dead space
- XA
conversion of A
Greek Letters
fraction of feed stream bypassing the vessel (vb/v)
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fraction of the total volume as dead space (Vd/V)
-
(t) 1/s
Dirac delta function, an ideal pulse occurring at time t = 0
-
s
life expectancy of a molecule
- 1/s
intensity function or escape probability function
-
s
space time or mean residence time 相似文献
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R. K. Saini K. R. Saad G. A. Ravishankar P. Giridhar N. P. Shetty 《Plant Systematics and Evolution》2013,299(7):1205-1213
Moringa oleifera is a less used, drought-tolerant tropical plant, rich in nutritionally and nutraceutically important bioactive compounds. It is native to India and now under cultivation in many countries, but no data is available on genetic variability. Three DNA marker techniques, i.e., random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and cytochrome P450 gene-based markers were used for the detection of genetic variability in eight Indian cultivars of M. oleifera, collected from various states of India. A total of 17 RAPD, 6 ISSR and 7 pairs of cytochrome P450-based markers generated 48.68, 48.57 and 40.00 % polymorphisms, respectively. The marker index (MI) for each of these marker systems (3.25 for RAPD, 4.73 ISSR and 2.95 for Cyt P450-based markers) suggest that ISSR markers are the most effective for assessment of genetic diversity. Based on the three types of marker data, the eight cultivars of M. oleifera were grouped into four sub-clusters in a dendrogram, but without any distinct geographical pattern. This suggests spread of planting material and high rates of gene flow through cross pollination. High bootstrap values (94.4 and 82.3) were obtained at major nodes of the dendrogram using the winboot software. The dendrogram and PCA plots generated from the binary data matrices of the three marker systems were found highly concordant to each other. This study reveals a huge genetic diversity among the cultivars and this can be utilised for conservation and cultivar development in breeding programmes to produce high yielding, nutritionally superior cultivars. 相似文献
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KV Thomas 《Biofouling》2013,29(1):73-86
Antifouling paint booster biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fate and behaviour data currently available in the public domain concerning antifouling paint booster biocides. 相似文献
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Riyaj S. Tamboli Rajani Giridhar Hardik P. Gandhi Ashish M. Kanhed Hemant M. Mande 《Journal of enzyme inhibition and medicinal chemistry》2016,31(5):704-713
The aim of this research work was to investigate a series of novel 5,6-diaryl-1,2,4-triazines (3a–3q) containing 3-morpholinoethylamine side chain, and to address their antiplatelet activity by in vitro, ex vivo and in vivo methods. All compounds were synthesized by environment benign route and their structures were unambiguously confirmed by spectral data. Compounds (3l) and (3m) were confirmed by their single crystal X-ray structures. Out of all the synthesized compounds, 10 were found to be more potent in vitro than aspirin; six of them were found to be prominent in ex vivo assays and one compound (3d) was found to have the most promising antithrombotic profile in vivo. Moreover, compound (3d) demonstrated less ulcerogenicity in rats as compared to aspirin. The selectivity of the most promising compound (3d) for COX-1 and COX-2 enzymes was determined with the help of molecular docking studies and the results were correlated with the biological activity. 相似文献
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