SciELO - Scientific Electronic Library Online

 
vol.45 issue12Radiological impact of phosphogypsum surface application in a no-till system in Southern BrazilClove oil as an anesthetic on Nile tilapia adults author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Pesquisa Agropecuária Brasileira

Print version ISSN 0100-204X

Abstract

FERNANDES JUNIOR, Paulo Ivan et al. Production and rheological behavior of exopolysaccharide synthesized by pigeonpea rhizobia isolates. Pesq. agropec. bras. [online]. 2010, vol.45, n.12, pp.1465-1471. ISSN 0100-204X.  http://dx.doi.org/10.1590/S0100-204X2010001200018.

The objective of this work was to evaluate the production and the rheological behavior of exopolysaccharides (EPS) produced by pigeonpea [Cajanus cajan (L.) Millsp.] rhizobia isolates, as well as to evaluate the similarity of these isolates through amplified ribosomal DNA restriction analysis technique. The bacteria were cultured in YM liquid media and the EPS were precipited with cold ethanol from culture broth. After that, they were vacuum dried, weighted, stored and resuspended in water to rheological evaluations. The three evaluated isolates showed differences on the production and productivity of EPS, and the isolate 8.1c stood out, with higher relative efficiency. The evaluated EPS showed non-newtonian and pseudoplastic behavior, however they also presented differences as to the apparent viscosity at the same shear rate. At the shear rate of 1 s-1 all isolates were different, while at the shear rate of 40 s-1 the isolates 53.5 and 30.6a2 were the same, differing from the isolate 8.1c. Genetic similarity of the isolates was in agreement with the rheology results, where bacteria that synthesized EPS with lower apparent viscosity presented the higher similarity

Keywords : Cajanus cajan; ARDRA; biopolymers; biological nitrogen fixation; technological innovation; rheology.

        · abstract in Portuguese     · text in Portuguese     · Portuguese ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License