Bacteria as cell factories for producing selenium nanoparticles: their synthesis by the rhizobacterium Azospirillum brasilense and characterisation

Background: Wound healing is a complex process necessary for repairing damaged tissues and preventing infection. Selenium nanoparticles (Se NPs) were known due to their antioxidant and antimicrobial effects, also niacin has angiogenesis and antioxidant effects that are important in wound healing. Objective: The present study was conducted to investigate the effect of Se NPs and niacin in reducing and accelerating the wound healing time in mice. Methods: A simple wet chemical method has been modified to synthesize Se NPs in order to investigate their effect and niacin on reducing the wound healing in 80 adult female albino mice (250 mm2 full thickness open excision wound) that were divided into eight groups (10 mice/each). After 30-days, the mice were sacrificed, blood and tissue samples were taken for analysis. Results: The results showed that the percentage of wound area had been significantly reduced in Se NPs and niacin treated groups compared to the positive control. The level of Vascular Endothelial cell Growth Factor and Collagenase I in Se NPs and niacin groups significantly exceed those of other groups while Nitric Oxide (NO) was significantly decreased in treated groups. Liver and kidney functions showed the lower toxicity effect of Se NPs and niacin. Skin tissue showed the wound healing effect of Se NPs and niacin by regenerating skin layer compared to the positive group. Conclusion: Se NPs and niacin play an important role in accelerating and reducing the time of wound healing while they were antagonistic to each other.

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SOYBEAN CULTIVATION IN A CROP-LIVESTOCK SYSTEM WITH Azospirillum brasilense INOCULATION

Revista Caatinga ◽

10.1590/1983-21252018v31n101rc ◽

2018 ◽

Vol 31 (1) ◽

pp. 1-8

Author(s):

MARCOS DA SILVA BRUM ◽

THOMAS NEWTON MARTIN ◽

VINÍCIUS SANTOS DA CUNHA ◽

LUIZ FERNANDO TELEKEN GRANDO ◽

ALEX TAGLIAPIETRA SCHONELL

Keyword(s):

Azospirillum Brasilense ◽

Block Design ◽

Experimental Period ◽

Height Control ◽

Grain Productivity ◽

Randomized Complete Block Design ◽

Grazing Systems ◽

Soybean Plants ◽

Santa Maria ◽

Livestock System

ABSTRACT The objective of this study was to evaluate the phytomorphological parameters of soybean in a crop-livestock system inoculated with Azospirillum brasilense. The experiment was conducted in Santa Maria, Brazil, for two agricultural years (2 Paper extracted from the doctoral thesis of the first author. 012/2013 and 2013/2014) in a randomized complete block design with three replications. In the winter, the black oat and ryegrass pasture was managed with sheep under different grazing systems: (I) - a conventional grazing (CG) system, where the animals remained in the pasture throughout the experimental period without any pasture height control; (II, III, and IV) - systems with post-grazing pasture heights of 10, 20, and 30 cm, respectively; and (NG) - one control without grazing. All treatments received two nitrogen doses (50 and 100 kg ha-1) and inoculation or no inoculation (A. brasilense). The soybean cultivar BMX Potência RR was sown using no-tillage on 16 November 2012 and 1 December 2013. In each plot, seven rows of plants with spacing of 0.45 m were used, and in four rows, the seeds were inoculated with the bacterium A. brasilense. The phytomorphological variables and grain productivity were evaluated. In a croplivestock system, soybean has better productivity when established on black oat and ryegrass pasture managed with post-grazing pasture heights of between 20 and 30 cm. Areas under conventional grazing in the winter led to smaller soybean plants with lower first and last pod heights. Inoculation with A. brasilense should not be used alone in soybean cultivation.

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