27 research outputs found
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Ultrafiltration based purification strategies for surfactin produced by bacillus subtilis lb5a using cassava wastewater as substrate
BACKGROUND: Bacillus subtilis synthesizes surfactin, a powerful surface-active agent. It has interesting potential applications. However, due to its high cost of production, commercial use is impracticable. The downstream processing represents ≈60% of production costs and the culture medium ≈30%. Many reports focused, separately, on production of surfactin using by-products (reduced cost) or the purification using synthetic medium. Therefore, the aim of this work was to evaluate, for the first time, the impact of using a by-product as fermentation medium on the downstream processing based on membrane filtration.
RESULTS: Membranes of PES-100-kDa efficiently retained surfactin micelles - the first step of ultrafiltration, whereas, the second step required membranes of 50-kDa to separate surfactin monomers from proteins. Ultrafiltration of crude biosurfactant was associated with fouling and/or concentration polarization resulting in lower purity than when synthetic medium was used. Further improvement in purity was achieved by partial removal of proteins prior to ultrafiltration by precipitation and extraction. The RMN and MALDI-TOFMS analyses identified 11 potential surfactin homologous composed by two amino acid sequences.
CONCLUSION: Production of surfactin using cassava wastewater as a low-cost culture medium and its purification by the 2-step ultrafiltration process is feasible, nevertheless, the higher protein content of this medium as compared to the synthetic one leads to a lower purity product; further increase in purity can be achieved by applying additional purification steps prior to ultrafiltration with the subsequent increased in process cost
The Influence Of Vegetable Oils On Biosurfactant Production By Serratia Marcescens.
The production of biosurfactant, a surface-active compound, by two Serratia marcescensstrains was tested on minimal culture medium supplemented with vegetable oils, considering that it is well known that these compounds stimulate biosurfactant production. The vegetable oils tested included soybean, olive, castor, sunflower, and coconut fat. The results showed a decrease in surface tension of the culture medium without oil from 64.54 to 29.57, with a critical micelle dilution (CMD(-1)) and CMD(-2) of 41.77 and 68.92 mN/m, respectively. Sunflower oil gave the best results (29.75 mN/m) with a CMD(-1) and CMD-2 of 36.69 and 51.41 mN/m, respectively. Sunflower oil contains about 60% of linoleic acid. The addition of linoleic acid decreased the surface tension from 53.70 to 28.39, with a CMD(-1) of 29.72 and CMD(-2) of 37.97, suggesting that this fatty acid stimulates the biosurfactant production by the LB006 strain. In addition, the crude precipitate surfactant reduced the surface tension of water from 72.00 to 28.70 mN/m. These results suggest that the sunflower oil's linoleic acid was responsible for the increase in biosurfactant production by the LB006 strain.98-100841-
Effects of supercritical carbon dioxide and thermal treatment on the inulin chemical stability and functional properties of prebiotic-enriched apple juice
Inulin-enriched apple juice was subjected to supercritical CO2 processing under different pressure levels (10, 15, and 20 MPa at 35 degrees C, 10 min and a 67% CO2 volume ratio) and to conventional thermal treatment (95 degrees C/1 min). Physicochemical properties (pH, soluble solid content, zeta-potential, particle size distribution and rheological behavior), organic acid (citric and malic) content, and phenolic compounds (UHPLC-ESI-MS/MS) were evaluated; moreover, antioxidant activity assays (DPPH and TEAC) as well as sugar content and fructo-oligosaccharide analyses (HPAEC-PAD) were performed. The increase in pressure levels reduced the particle size suspended in the functional juice. Supercritical processing was able to preserve all compounds responsible for the functional properties of the beverage as well as the natural nutritional components such as sorbitol, glucose, fructose and sucrose. The emerging technology did not reduce the antioxidant activity of the juice samples, thus maintaining their functionality. The inulin chemical profile was not altered by the supercritical CO2 processing, while in the thermally treated sample, there was a breakdown of the inulin chain into units of short-chain fructo-oligosaccharides. Overall, supercritical technology may be an interesting option for inulin-enriched apple juice processing125CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302423/2015-0não tem2015/22226-
Clarification and concentration of oligosaccharides from artichokeextract by a sequential process with microfiltration and nanofiltrationmembranes
Artichoke solid waste is considered a cheap fructooligosaccharides source. The extract from this material contains suspended solids, macromolecules and prebiotic sugars. The prebiotic sugars need to be clarified, purified and concentrated to increase its value. In this study, we evaluated the technical feasibility of sequential microfiltration (to clarify the artichoke extract) and nanofiltration (to purify and concentrate the prebiotic sugars). The investigation was carried out in laboratory scale, using different microfiltration and nanofiltration membranes subjected to different operation pressures. Microfiltration was able to clarify the extract with almost 100% of prebiotic sugars recovered in permeate. Microfiltration processes presented flux decline (the final flux was between 60 and 80% of the initial one) caused by cake layer formation, as observed by surface analysis. The membrane that presented the lowest flux decline and less solids deposition on its surface (polyethersulfone with a pore size of 0.05 μm), had its permeate subjected to nanofiltration. In this last step, 100% of retention of prebiotic sugar was obtained, mainly using polyamide membrane with molecular weight cut off of 150–300 Da. The sequential process allowed to produce a concentrate fraction can be used as an ingredient on foodstuff applications180120128CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP143885/2011-1; 304475/2013-033003017029P42006/03263-9; 2009/50591-0; 2009/50593-
Newly isolated microorganisms with potential application in biotechnology
Nowadays, food, cosmetic, environmental and pharmaceutical fields are searching for alternative processes to obtain their major products in a more sustainable way. This fact is related to the increasing demand from the consumer market for natural products to substitute synthetic additives. Industrial biotechnology appears as a promising area for this purpose; however, the success of its application is highly dependent of the availability of a suitable microorganism. To overcome this drawback, the isolation of microorganisms from diverse sources, including fermented food, adverse environments, contaminated samples or agro-industrial wastes is an important approach that can provide a more adaptable strain able to be used as biocatalyst and that exhibit resistance to industrial conditions and high yields/productivities in biotechnological production of natural compounds. The aim of this review is to provide a solid set of information on the state of the art of isolation and screening studies for obtaining novel biocatalysts able to produce natural compounds, focusing in aromas, biosurfactants, polysaccharides and microbial oils372319339CAPES - Coordenação de Aperfeiçoamento de Pessoal e Nível SuperiorCNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo à Pesquisa Do Estado De Minas GeraisFAPESP – Fundação de Amparo à Pesquisa Do Estado De São PauloNão tem460897/2014-4; 140513/2016-72013/18390-0APQ-01056-17Polysaccharide
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Antioxidant Potential Of Rat Plasma By Administration Of Freeze-dried Jaboticaba Peel (myrciaria Jaboticaba Vell Berg).
The effect of the intake of freeze-dried jaboticaba peel powder on the antioxidant potential of rats' blood plasma was investigated in two experiments. In the first, 35 male rats, divided into 5 groups, received 7 mg of anthocyanins/100 g of body weight, by gavage. The blood was withdrawn 0, 30, 60, and 120 min after gavage. The antioxidant capacity was evaluated in plasma by ORAC and TEAC. There was no significant difference in the plasmatic antioxidant potential among the groups. In the second experiment, 40 male rats were divided into 4 groups that consumed, respectively, 0, 1, 2, and 4% of freeze-dried jaboticaba peel powder added to their diet. An increase in the plasmatic antioxidant potential was observed for groups that received 1 and 2% of jaboticaba peel powder (1.7 times by TEAC method and 1.3 times by ORAC); however, the group that received 4% of the powder did not show antioxidant effects according to the methods used.592277-8
Obtaining a novel mucilage from mutamba seeds exploring different high : intensity ultrasound process conditions
We evaluated the effect of ultrasonic power (200-600 W) and process time (1-7 min) on the recovery of a novel polysaccharide from mutamba (Guazuma ulmifolia Lam.) seeds applying high-intensity ultrasound. Ultrasound process conditions intensification gradually was removing the mucilage layer around the hydrated seeds. Then, the scanning electron micrographs showed that the mucilage was removed completely at the highest applied energy density (10,080 J/mL). Although the colour of mutamba seed mucilage (MSM) have been changed due to increase of energy density, it not affects its practical use because the MSM can be purified to remove impurities. The results obtained in this study demonstrated that the ultrasound process conditions intensification did not affect the primary structure of MSM according to zeta-potential, FTIR spectrum, and monosaccharide residues data. In conclusion, ultrasound process conditions intensification allows the full recovery of the MSM at a short process time (7 min) without altering its quality and the primary structure55332340CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302423/2015-023038.000795/2018-612015/50333-1; 2015/22226-
Mutamba seed mucilage as a novel emulsifier : stabilization mechanisms, kinetic stability and volatile compounds retention
We studied the use of a novel polysaccharide obtained from mutamba (Guazuma ulmifolia Lam.) seeds as an emulsifying agent. Orange peel oil-in-water emulsions stabilized by mutamba seed mucilage (MSM), gum acacia, and modified starches were produced by high-intensity ultrasound. The structural feature and interfacial tension data demonstrated the MSM has emulsifying property. MSM was able to stabilize an oil-in-water emulsion and retained effectively the volatile compounds from orange peel oil. Furthermore, the emulsion stabilized by MSM decreased the loss of limonene, myrcene, alpha-pinene, and linalool during the storage. MSM was able to increase the continuous phase viscosity, which improved the emulsion stability and delayed the volatile compounds release by decreasing the oil droplet motion. Additionally, the ability of MSM to adsorb rapidly into the oil-water interface aided to stabilize the emulsion. The emulsion stabilized by MSM showed better stability and control release than emulsions stabilized by gum acacia and modified starches. In conclusion, the MSM can be used as a natural emulsifying and thickening agent to prepare stable emulsions with high encapsulation efficiency of volatile compounds97CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302423/2015-023038.000795/2018-612015/22226-6, 2015/50333-