Estudo da estrututa de exopolissacarideos produzidos por duas especies de Rhizobium e uma de Bradyhizobium isolados de solo de cultivar Feijão de corda (Vigna unguiculata L.)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2000

RESUMO

Three new extracellular biopolymers obtained by aerobic fennentation from the Rhizobium strains "NFB", "RFB" and Bradyrhizobium strain "79" were developed. Medium I (0.1 % yeast extract, 0.02 % MgSO4.7H2O, 0.1 % K2HPO4) with 10% sucrose was used for the production of RFB and 79 EPS, and with 3% mannitol for NFB. NFB and RFB were fennented for 10 days, and 79 for 14 days, at 30°C. To RFB and 79 EPS the maximal production of EPS was 2.7 g/L, and for 79 NFB EPS it was 1.7 g/L. After cell isolation, protein represented on average 2.5 % of the EPS, and was separated using TCA. HPLC-SEC-Rl with the columns TSK-30 and 40 XL, was used, and molecular weight (MW) to the order of 106D were obtained. The dependence ofthe 79 EPS on MW in relation to the fermentation time, was also tested. [ab2O = 0° , +170° and +85° were obtained for the 79 EPS, RFB and NFB, respectively...Note: The complete abstract is available with the full electronic digital thesis or dissertations.

ASSUNTO(S)

analise cromatografica polimeros polissacarideos

ACESSO AO ARTIGO

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