scholarly journals A Smart Strategy to Improve t-Resveratrol Production in Grapevine Cells Treated with Cyclodextrin Polymers Coated with Magnetic Nanoparticles

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 991 ◽  
Author(s):  
Lorena Almagro ◽  
Alicia De Gea-Abellán ◽  
María Isabel Rodríguez-López ◽  
Estrella Núñez-Delicado ◽  
José Antonio Gabaldón ◽  
...  

One of the most successfully procedures used to increase the production of t-resveratrol in Vitis vinifera suspension-cultured cells is the application of cyclodextrins (CDs) and methyl jasmonate (MJ) as elicitors. In particular, β-CDs are characterized by their chemical structure which makes them special, not only by acting as elicitors, but also because they are compounds capable of trapping high added-value hydrophobic molecules such as t-resveratrol. However, the use of β-CDs as elicitors increases the production costs of this compound, making their industrial exploitation economically unfeasible. Therefore, the development of β-CDs recovery strategies is necessary to provide a viable solution to their industrial use. In this work, carboxymethylated and hydroxypropylated β-CDs have been used to form polymers using epichlorohydrin (EPI) as a cross-linking agent. The polymers were coated to Fe3O4 nanoparticles and were jointly used with MJ to elicit V. vinifera suspension-cultured cells. Once elicitation experiments were finished, a magnet easily allowed the recovery of polymers, and t-resveratrol was extracted from them by using ethyl acetate. The results indicated that the production of t-resveratrol in the presence of free carboxymethyl-β-CDs was much lower than that found in the presence of carboxymethyl-β-cyclodextrins-EPI polymer coated magnetic nanoparticles. In addition, the maximal levels of t-resveratrol were found at 168 h of elicitation in the presence of 15 g/L hydroxypropyl-β-CDs polymer coated magnetic nanoparticles and MJ, and non-t-resveratrol was found in the extracellular medium, indicating that all the t-resveratrol produced by the cells and secreted into the culture medium was trapped by the polymer and extracted from it. This work also showed that polymers can be regenerated and reused during three cycles of continuous elicitation since the induction and adsorption capacity of hydroxypropyl-β-CDs polymer-coated magnetic nanoparticles after these cycles of elicitation remained high, allowing high concentrations of t-resveratrol to be obtained.

1992 ◽  
Vol 84 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Stephen P. Lee ◽  
Baolong Zhu ◽  
Tony H. H. Chen ◽  
Paul H. Li

2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses, five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan (6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide, which contained features of type-II arabinogalactans and glucuronomannans (65%).


2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses, five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan (6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide, which contained features of type-II arabinogalactans and glucuronomannans (65%).


Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.


2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Andrew Paul Gutierrez ◽  
Luigi Ponti ◽  
Keshav R. Kranthi ◽  
Johann Baumgärtner ◽  
Peter. E. Kenmore ◽  
...  

Abstract Background The implementation of hybrid Bt cotton unique to India has been heralded as a grand success by government agencies, seed companies and other proponents, and yet yields have stagnated at low levels and production costs have risen 2.5–3-fold. The low-yield hybrid cotton system of India contributes thousands of farmer suicides to the annual national toll. Conceptual and methodological barriers have hindered bioeconomic analysis of the ecological and social sustainability of such cross-scale agro-ecological problems in time and geographic space, under global technology and climate change. As a paradigm shift, we use conceptually simple, parameter-sparse, theoretically based, mechanistic, weather-driven physiologically based demographic models (PBDMs) to deconstruct the bio-economics of the Indian cotton system. Results Our analysis of Indian hybrid cotton system explains some extant ecological and economic problems, and suggests a viable solution. Specifically, the model accurately captured the age-stage mass dynamics of rainfed and irrigated cotton growth/development and the interactions with the key pest pink bollworm across five south-central Indian states, and enabled identification of proximate bioeconomic factors responsible for low yield and their relationship to farmer suicides. The results are reinforced by analysis of Ministry of Agriculture annual state-level data. We explain why short-season, high-density non-GM cotton is a highly viable solution for Indian cotton farmers in rainfed and irrigated cotton areas of the five states, and possibly nationally. The transition from a theoretical bioeconomic construct to a real-world regional bioeconomic analysis proved seamless. Conclusions The hybrid long-season Bt technology for rainfed and irrigated cotton is unique to India, and is a value capture mechanism. This technology is suboptimal leading to stagnant yields, high input costs, increased insecticide use, and low farmer incomes that increase economic distress that is a proximate cause of cotton farmer suicides. The current GM Bt technology adds costs in rainfed cotton without commensurate increases in yield. Non-GM pure-line high-density short-season varieties could double rainfed cotton yield, reduce costs, decrease insecticide use, and help ameliorate suicides. The GM hybrid technology is inappropriate for incorporation in short-season high-density varieties.


2002 ◽  
Vol 43 (11) ◽  
pp. 1314-1322
Author(s):  
Tsuneo Hakoyama ◽  
Tadashi Yokoyama ◽  
Hiroshi Kouchi ◽  
Ken-ichi Tsuchiya ◽  
Hisatoshi Kaku ◽  
...  

1996 ◽  
Vol 183 (4) ◽  
pp. 1447-1459 ◽  
Author(s):  
F P Huang ◽  
G J Feng ◽  
G Lindop ◽  
D I Stott ◽  
F Y Liew

MRL/MP-lpr/lpr (MRL/lpr) mice develop a spontaneous autoimmune disease. Serum from these mice contained significantly higher concentrations of nitrite/nitrate than serum from age-matched control MRL/MP-+/+ (MRL/+), BALB/c or CBA/6J mice. Spleen and peritoneal cells from MRL/lpr mice also produced significantly more nitric oxide (NO) than those from the control mice when cultured with interferon (IFN) gamma and lipopolysaccharide (LPS) in vitro. It is interesting to note that peritoneal cells from MRL/lpr mice also produced markedly higher concentrations of interleukin (IL) 12 than those from MRL/+ or BALB/c mice when cultured with same stimuli. It is striking that cells from MRL/lpr mice produced high concentrations of NO when cultured cells from MRL/+ or BALB/c mice. The enhanced NO synthesis induced by IFN-gamma/LPS was substantially inhibited by anti-IL-12 antibody. In addition, IL-12-induced NO production can also be markedly inhibited by anti-IFN-gamma antibody, but only weakly inhibited by anti-tumor necrosis factor alpha antibody. The effect of IL-12 on NO production was dependent on the presence of natural killer and possibly T cells. Serum from MRL/lpr mice contained significantly higher concentrations of IL-12 compared with those of MRL/+ or BALB/c control mice. Daily injection of recombinant IL-12 led to increased serum levels of IFN-gamma and NO metabolites, and accelerated glomerulonephritis in the young MRL/lpr mice (but not in the MRL/+ mice) compared with controls injected with phosphate-buffered saline alone. These data, together with previous finding that NO synthase inhibitors can ameliorate autoimmune disease in MRL/lpr mice, suggest that high capacity of such mice to produce IL-12 and their greater responsiveness to IL-12, leading to the production of high concentrations of NO, are important factors in this spontaneous model of autoimmune disease.


1982 ◽  
Vol 9 (3) ◽  
pp. 297 ◽  
Author(s):  
PJ Larkin ◽  
W Scowcroft ◽  
AE Geissler ◽  
GF Katekar

The phytotropins l-(2'-carboxyphenyl)-3-phenylpropane-1,3-dione (CPP) and 5-(2-carboxyphenyl)- 3-phenylpyrazole (CPD) reduced the net efflux of radiolabel from suspension-cultured cells treated with [14C]2,4-dichlorophenoxyacetic acid when present at concentrations comparable to those that inhibit polar transport of auxins in bean petioles. These phytotropins stimulated division of protoplasts of both Nicotiana debneyi and Petunia hybrida at concentrations of exogenous auxins that were otherwise suboptimal for divisions. The results are consistent with the proposal that phytotropins interact with specific receptors to reduce auxin efflux, resulting in increased intracellular auxin concentrations.


Plant Science ◽  
2000 ◽  
Vol 150 (1) ◽  
pp. 59-69 ◽  
Author(s):  
Anna E Schulte ◽  
Eva M Llamas Durán ◽  
Robert van der Heijden ◽  
Robert Verpoorte

1993 ◽  
Vol 13 (6) ◽  
pp. 3282-3290
Author(s):  
X Li ◽  
D C Beebe

Crystallins are proteins that accumulate to very high concentrations in the fiber cells of the lens of the eye. Crystallins are responsible for the transparency and high refractive index that are essential for lens function. In the chicken embryo, delta-crystallin accounts for more than 70% of the newly synthesized lens proteins. We used density labeling and gene-specific polymerase chain reaction (PCR) to determine the mechanism regulating the expression of the two very similar delta-crystallin genes. Newly synthesized RNA was separated from preexisting RNA by incubating the lenses with 15N- and 13C-labeled ribonucleosides and then separating newly synthesized, density-labeled RNA from the bulk of light RNA by equilibrium density centrifugation in NaI-KI gradients. The relative abundances of the two crystallin mRNAs in the separated fractions were then determined by PCR. This method permitted the quantitation of newly synthesized processed and unprocessed delta-crystallin mRNAs. Additional studies used intron- and gene-specific PCR primers to determine the relative expression of the two delta-crystallin genes in processed RNA and unprocessed RNA extracted from different regions of the embryonic lens. Results of these tests indicated that the differential expression of the delta-crystallin genes was regulated primarily at the level of transcription. This outcome was not expected on the basis of the results of previous studies, which used in vitro transcription and transfection methods to evaluate the relative strengths of delta-crystallin promoter and enhancer sequences. Our data suggest that the cultured cells used in these earlier studies may not have provided an accurate view of delta-crystallin regulation in the intact lens.


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