Minerals consumption by Acetobacter xylinum on cultivation medium on coconut water

The objective of this work is to verifying the consume of the minerals K, Na, Fe, Mg, P, S-SO4-2,B,N Total Kjedahl (NTK), NO3--N, and NH4+-N in the production of bacterial cellulose by Acetobacter xylinum, according to the medium and the manner of cultivation. The fermentative process was in ripe and green coconut water. K and Na were determined by flame emission photometry, Mg and Fe by atomic absorption spectrophotometry, P by molecular absorption spectrophotometry, S-SO4-2 by barium sulphate turbidimetry, B by Azomethin-H method, NTK by Kjeldahl method, N-NO3-and N-NH4+ by vapor distillation with magnesium oxide and Devarda's alloy, respectively. In Fermentation of ripe coconut water there were higher consumption of K (69%), Fe (84,3%), P (97,4%), S-SO2-2 (64,9%), B (56,1%), N-NO3 (94,7%) and N-NH4+ (95,2%), whereas coconut water of green fruit the most consumed ions were Na (94,5%), Mg (67,7%) and NTK (56,6%). The cultivation under agitation showed higher mineral consumption. The higher bacterial cellulose production, 6 g.L-1, was verified in the coconut water fermentative in ripe fruit, added KH2PO4, FeSO4 and NaH2PO4 kept under agitation.

Bioremediation: an important alternative for soil and industrial wastes clean-up.

Industrial and environmental biotechnology are going to new paths, resulting in processes with "clean technologies", with the maximum production and the less residues. Technologies of remediation and bioremediation are continuously being improved using genetically modified microorganisms or those naturally occurring, to clean residues and contaminated areas from toxic organics. Bioremediation of soils, water and marine environments has many advantages but at the same time it is a challenge for the researchers and engineers. Consequently, it is extremely important to carry out feasibility study based on pilot-testing before starting a remediation project in order to determine the best conditions for the process. The article presents a brief review of bioremediation including the description of the different methods applied to soil and industrial wastes, and, finally, some experiences of solid-state fermentation in relation to bioremediation.