Wyniki wyszukiwania

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Physiological and molecular level studies on the toxicity of silver nanoparticles in germinating seedlings of mung bean (Vigna radiata L.)

100%

Nair P. M. G., Chung I. M.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 01

In the present study, the toxic effect of silver nanoparticles was studied in seedlings of economicallyimportant food crop mung bean (Vigna radiata L.). The plants were grown in 1/2 MS agar medium containing 0, 5, 10, 20, and 50 mg/L of silver nanoparticles for 21 days. The toxic effects were studied using different parameters such as growth, chlorophyll, and proline contents, reactive oxygen species (ROS) generation, lipid peroxidation, changes in mitochondrial membrane potential (DWm), and oxidative stress responsive gene expression. The shoot length and weight was significantly reduced upon exposure to 50 mg/L of silver nanoparticles. Significant reduction in root elongation and weight was observed upon exposure to 20 and 50 mg/L of silver nanoparticles. The total chlorophyll content significantly reduced after exposure to 50 mg/L of silver nanoparticles. However, proline content was increased significantly upon exposure to 20 and 50 mg/L of silver nanoparticles. The hydrogen peroxide level and lipid peroxidation levels increased significantly in roots after exposure to 20 and 50 mg/L of silver nanoparticles. Histochemical staining with nitroblue tetrazolium showed a concentration-dependant increase in superoxide formation in roots. Roots treated with 20, 70-dichlorodihydro-fluorescein diacetate and 3, 30-diaminobenzidine showed a concentration-dependant increase in ROS generation. Exposure to increasing concentrations of silver nanoparticles has resulted in changes in DWm in roots as revealed by increased Rhodamine 123 fluorescence. Gene expression analysis using real-time polymerase chain reaction showed changes in the relative mRNA expression of CuZn-SOD, CAT, and APX genes indicating the plants’ antioxidative defense responses under silver nanoparticle stress.

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Copper oxide nanoparticle toxicity in mung bean (Vigna radiata L.) seedlings: physiological and molecular level responses of in vitro grown plants

80%

Gopalakrishnan Nair P. M., Kim S.-H., Chung I. M.

Acta Physiologiae Plantarum

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2014

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tom 36

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nr 11

In this study, the toxic effect of copper oxide nanoparticles (CuONPs) at the physiological and molecular level was investigated in mung bean (Vigna radiata L.) plants. The seedlings were grown in half strength Murashige and Skoog medium supplemented with different concentrations of CuONPs (0, 20, 50, 100, 200 and 500 mg l⁻¹) for 21 days under controlled growth conditions. Exposure to 200 and 500 mg l⁻¹ of CuONPs significantly reduced shoot length and biomass. Significant reduction in root length and biomass was observed upon exposure to all concentrations of CuONPs. Retardation of primary and lateral root growth was observed upon exposure to different concentrations of CuONPs. At 100, 200 and 500 mg l⁻¹ of CuONPs exposure, the total chlorophyll contents reduced significantly. Exposure to different concentrations of CuONPs has not resulted in any significant change in carotenoid contents. The proline content significantly increased upon exposure to 100, 200 and 500 mg l⁻¹ of CuONPs. Significant increase in hydrogen peroxide content and lipid peroxidation was observed in roots upon exposure to 20, 50, 100, 200 and 500 mg l⁻¹ of CuONPs. Histochemical staining with nitroblue tetrazolium and treatment with 30 -(p-hydroxyphenyl) fluorescein indicated a concentration-dependent increase in reactive oxygen species generation in roots. Exposure to CuONPs has resulted in excess lignification of roots cells as revealed by phloroglucionol-HCl staining. Gene expression analysis using real-time polymerase chain reaction showed modulations in the expression of CuZn superoxide dismutase, catalase and ascorbate peroxidase genes in roots of CuONPs exposed plants.

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Establishment of Gymnema sylvestre hairy root cultures for the production of gymnemic acid

71%

Nagella P., Thiruvengadam M., Jung S. J., Murthy H. N., Chung I. M.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 10

Gymnema sylvestre is an important medicinal plant that bears bioactive compound namely gymnemic acid. In the present study, G. sylvestre was transformed by Agrobacterium rhizogenes. Seedling explants namely roots, stems, hypocotyls, cotyledonary nodal segments, cotyledons and young leaves were inoculated with A. rhizogenes strain KCTC 2703. Transformed (hairy) roots were induced from cotyledons and leaf explants. Six transgenic clones of hairy roots were established and confirmed by polymerase chain reaction (PCR) and RT-PCR using rolC specific primers. Hairy roots cultured using MS liquid medium supplemented with 3 % sucrose showed highest accumulation of biomass (97.63 g l-1 FM and 10.92 g l-1 DM) at 25 days, whereas highest accumulation of gymnemic acid content (11.30 mg g-1 DM) was observed at 20 days. Nearly 9.4-fold increment of biomass was evident in suspension cultures at 25 days of culture and hairy root biomass produced in suspension cultures possessed 4.7-fold higher gymnemic acid content when compared with the untransformed control roots. MSbased liquid medium was superior for the growth of hairy roots and production of gymnemic acid compared with other culture media evaluated (B5, NN and N6), with MS-based liquid medium supplemented with 3 % sucrose was optimal for secondary metabolite production. The current results showed great potentiality of hairy root cultures for the production of gymnemic acid.

Ograniczanie wyników

3 Acta Physiologiae Plantarum

3 Chung I. M.

1 Gopalakrishnan Nair P. M.

1 Jung S. J.

1 Kim S.-H.

1 Murthy H. N.

1 Nagella P.

1 Nair P. M. G.

1 Thiruvengadam M.

1 2015

1 2014

1 2013

Physiological and molecular level studies on the toxicity of silver nanoparticles in germinating seedlings of mung bean (Vigna radiata L.)

Copper oxide nanoparticle toxicity in mung bean (Vigna radiata L.) seedlings: physiological and molecular level responses of in vitro grown plants

Establishment of Gymnema sylvestre hairy root cultures for the production of gymnemic acid