Produção de biomassa de Bacillus sp. RAB9 por fermentação submersa

Abstract

The growth-promoting bacteria in plants (BPCP) represents a functional portion of the active biota soil rhizosphere are present in rhizoplane and within host plants The biotechnological use of these bacteria has intensified in recent years The genus Bacillus has been continually cited in studies related to growth promotion in plant species Some species can be applied as a seed treatment organs for the vegetative propagation and seedling Therefore this study aimed to assess the biomass of Bacillus sp (RAB9) with potential use in promoting growth of banana plantlets The strain Bacillus sp (RAB9) belonging to the group of epiphytic bacteria was isolated from radish from the Culture Collection of the Laboratory of Fitobacteriologia Federal Rural University of Pernambuco The experiments were performed on an orbital shaker and batch reactor In orbital shaker was studied growth curve of strain at 30°C to observe their exponential phase For the production of biomass were observed the effects of adding the content of peptone (5 to 50 g.L-1) in NYD medium (meat extract yeast extract meat peptone and dextrose) addition of secondary elements (K2HPO4 and MgSO4) and inorganic nitrogen source ((NH4)2SO4) In batch reactor tests were conducted with different air flows in simple batch and fed batch with a comparison with the modified medium The fermentations presented in the reactors foaming tests were made with vegetable oils (corn canola sunflower soybean) and to verify the best mineral defoamer Later tests were quantified biomass residual sugar residual nitrogen and ammonia nitrogen With the results noted the importance of the addition of elements (MgSO4 and (NH4)2SO4) in half NYD and air flow on the growth of strain With the studied parameters were determined the best conditions for the production of Bacillus sp RAB9