ABSTRACT
BACKGROUND This study aimed to produce carotenoids of two bacterial strains obtained and isolated from Caatinga soil in Northeastern Brazil and to evaluate their antioxidant and photoprotective activities. The morphological identification of bacteria was performed by Gram staining and molecularly confirmed through the 16S rRNA gene. The production of carotenoids was performed on two 23 factorial designs to analyze the influence of independent variables (temperature range, luminosity, agitation, spiral presence, and bacterial isolate type) for maximum carotenoid yield. The selected condition has been transferred to a bioreactor (10L). The identification of carotenoids was performed by liquid chromatography (HPLC) and mass spectrometry (LC-MS). Antioxidant activity was determined by inhibiting the bcarotene/linoleic acid system and the effectiveness as sunscreen was measured through its sun protection factor (SPF). RESULTS The results revealed that the isolates FT-7.22 and FT-5.12 were identified as Kocuria palustris; producers of a rare C50 carotenoid sarcinaxanthin. This is the first report on the production of carotenoids by this species from the Caatinga Domain. The pigment that was obtained from the Tryptic Soy Broth (TSB) medium in the best conditions of the factorial designs (increased agitation, aeration, and light exposure) exhibited a significant increase in the carotenoid production. The isolated FT-7.22 reached a higher sarcinaxanthin concentration (112,480 lg/L), and it exhibited promising antioxidant (76.53 ± 0.09%) and photoprotective activities (SPF = 9.36 ± 0.52). CONCLUSIUON This study demonstrated the ability of K. palustris to produce carotenoid sarcinaxanthin with antioxidant and photoprotective activities so that it can be applied in cosmetic formulations. How to cite: Mendes-Silva TCD, Vidal EE, de Souza RFR, et al. Production of carotenoid sarcinaxant
Subject(s)
Carotenoids/chemistry , Micrococcaceae/metabolism , Micrococcaceae/chemistry , Antioxidants/chemistry , Brazil , Carotenoids/pharmacology , Antioxidants/pharmacologyABSTRACT
The aim of this study was to evaluate the influence of recycling the liquid fraction of pretreatment with alkaline hydrogen peroxide (AHP) on the hydrolysis of corn stover. Corn stover was pretreated in the traditional condition with 7.5% v/v H2O2. After pretreatment, the solids were separated from the liquid fraction and five successive reuse cycles of the liquid fraction were tested. The solid fraction from pretreatment in each recycle was submitted to enzymatic hydrolysis. The number of recycles had a linear negative effect (R2=0.98) on biomass delignification efficiency and also affected negatively the enzymatic conversion efficiency. Despite the decrease in efficiency after each recycling step, reuse of the liquid fraction leads to reduction in water, H2O2 and NaOH consumption of up to 57.6%, 59.6% and 57.6%, respectively. These findings point to an efficient recycling technology, which may reduce costs and save water.
Subject(s)
Hydrogen Peroxide , Recycling , Zea mays , Biomass , HydrolysisABSTRACT
In the present work, we evaluated the mineral composition of three sugarcane varieties from different areas in northeast Brazil and their influence on the fermentation performance of Saccharomyces cerevisiae. The mineral composition was homogeneous in the different areas investigated. However, large variation coefficients were observed for concentrations of copper, magnesium, zinc and phosphorus. Regarding the fermentation performances, the sugarcane juices with the highest magnesium concentration showed the highest ethanol yield. Synthetic media supplemented with magnesium also showed the highest yield (0.45 g g(-1)) while the excess of copper led to the lowest yield (0.35 g g(-1)). According to our results, the magnesium is the principal responsible for the increase on the ethanol yield, and it also seems to be able to disguise the inhibitory effects of the toxic minerals present in the sugarcane juice.
