Description
In this work, the potential of Serratia marcescens UCP 1549, gram-negative bacterium
isolated from the soil of the semi-arid region of Pernambuco, in the production of
prodigiosin under solid state fermentation (FES). Therefore, different agro-industrial
substrates (wheat bran, sugarcane bagasse, instant noodle residue, tangerine bark,
pineapple peel and pineapple crown), were used in the formulation of the means of
production of prodigiosin by FES, obtaining the maximum yield of the red pigment
(119.8 g/kg of dry substrate) in the medium consisting of 5 g of wheat bran and
humidifiable solution containing sais (KH2PO4, K2HPO4, MgSO4.7H2O and
(NH4)2SO4) and 5% post-frying soybean oil. The pigment was identified as prodigiosin
by the maximum peak absorbance at 535 nm, Rf of 0.9 in CCD and the functional
groups identified by the infrared spectrum (FTIR). Prodigiosin showed stability at
different temperature values (0 º C, 10 º C, 50 º C, 70 º C and 100 º C), pH (2, 4, 6, 8,
10, 12 and 14) and concentrations of NaCl (0.1%, 0.2%, 0.5%, 1% and 5%) confirming
its potential for application in various industrial, pharmaceutical and medical areas. The
raw pigment produced did not show phytotoxic effects in concentrations (0.1%, 0.5%
and 1%) for cabbage seeds (Brassica oleracea), lettuce (Lactuca sativa), onion (Allium
cepa) and cucumber (Cucumis sativus). Toxicity tests using the microcrustacean
Artemia salina, as an aquatic bioindicator, demonstrated low prodigiosin toxicity in
concentrations (0.01 mg / L, 0.1 mg / L, 1 mg / L, 10 mg / L and 100 mg / L). The
pigment of S. marcescens in antimicrobial action showed a minimum inhibitory
concentration (MIC) significant for the bacteria Klebsiella pneumoniae (UCP 1574),
Staphylococus aureus (UCP 1576) and Enterococcus faecalis (UCP 1577). Therefore,
the results obtained showed the biotechnological potential of S. marcescens UCP 1549
in the production of prodigiosin by FES, using agrifood substrates, which can contribute
to reduce production costs, in addition to minimizing the environmental impact.