Minerals consumption by Acetobacter xylinum on cultivation medium on coconut water

Abstract

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.

Keywords: Acetobacter xylinum; bacterial cellulose; minerals.

Figure 1

Scores (A) and weights (B) graphics of PCA analysis of the mineral concentration percentage in the fermentation treatments: FRCW-0 h (▲) and FRCW-168 h (▼), FGCW-0 h (■) and FGCW-168 h (□).