Navegando por Palavras-chave "Surfactin"
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- ItemSomente MetadadadosAvaliação do potencial biossurfactante de isolados do gênero Bacillus, obtidos de processos de compostagem(Universidade Federal de São Paulo (UNIFESP), 2020-07-07) Barros, Caroline De Almeida [UNIFESP]; Vasconcellos, Suzan Pantaroto de [UNIFESP]; Universidade Federal de São PauloBiosurfactants are produced by microorganisms and due to their physicalchemical properties, such as the ability to emulsify and stabilize non-miscible fluids, they have several applications in the industry, including the food, pharmaceutical, cosmetic, and environmental contexts, such as in bioremediation from hydrocarbon contaminated sites. In this sense, the search for new species of microorganisms that produce hydrocarbon-degrading biosurfactants is growing, covering the most diverse areas and specialties, making it a promising alternative, since such biocomposites have low production costs and are toxic to the environment. For this purpose, in the present study, the emulsification potential and surface activity of 24 bacterial isolates obtained from the composting process, adopted at the Fundação Parque Zoológico de São Paulo (FPZSP), were evaluated. It was possible to select 4 (four) isolates (84, 1609, 1539 and 1594), regarding the emulsifying potential, based on calculations of the emulsification index (E24) on diesel oil. The same isolates also stood out in terms of the surface activity assessed by tensiometric measurements, via the drop collapse method and Ring Method. Values close to 31 mN / m were observed for such bacterial isolates, proving their ability to break the tension between fluid interfaces. In terms of reaction yield, the same microorganisms showed an average production of 5 g of tensoactive compounds with biosurfactant activity, for each 1 g of cultured cells. Characterization analyzes of the isolates, based on DNA extraction, amplification and sequencing of the 16S rDNA, allowed their affiliation with the genus Bacillus sp. Such a bacterial genus is widely described in the literature as a producer of tensoactives with biosurfactant activities, such as surfactin, due to the presence of the Srf family genes. In this sense, the present study aims for the next period the spectroscopic characterization of biosurfactant and bio-emulsifying compounds produced by Bacillus sp. selected, as well as detecting, by sequence homology, the presence of genes related to surfactin production. In the present study, we verified an amplification of the 675 bp and 201 bp bands, which represent an agreement with the literature of the sfp and srfAA genes, respectively.
- ItemAcesso aberto (Open Access)Bioconversion of low-cost brewery waste to biosurfactant: an improvement of surfactin production by culture medium optimization(Colin Webb, 2021-05-11) Corrêa Nazareth, Talita; Planas Zanutto, Conrado; Maass, Danielle [UNIFESP]; Ulson de Souza, Antônio Augusto; Guelli Ulson de Souza, Selene Maria de Arruda; http://lattes.cnpq.br/3431482044015696Trub is the second-largest residue from brewing industry (250 thousand tons/year) and, due to the presence of high amounts of carbon and nitrogen, it is a potential source of reducing sugars and nitrogen for biological processes. Therefore, this work aimed to enhance surfactin production by B. subtilis using Trub as a carbon source. The effect of nitrogen sources on biosurfactant production was investigated by a Full Factorial Design (2²). Yeast extract and its interaction with peptone presented a statistically significant effect on the response variable of surface tension (ST). ST was described by a linear regression model (R² = 0.93). The effect of metals supplementation on the culture medium was also investigated, where the volumetric productivity increased from 2.98 to 7.43 mg.L-1.h-1 for the medium without (M-I) and with metals (M-II), respectively. After 28h, 210.11 mg.L-1 was obtained in the batch culture with MII medium, being higher than the maximum surfactin concentration achieved after 52 h (121.80 mg.L-1) for M-I medium. The biosurfactant production in bioreactor was successfully performed since a concentrated extract was obtained in the foam collected, reaching the maximum of 1118.20 mg.L-1 of surfactin.
- ItemAcesso aberto (Open Access)Impact of oxygen supply on surfactin biosynthesis using brewery waste as substrate(Elsevier, 2021-03-15) Zanutto, Talita Corrêa Nazareth; Zanutto, Conrado Planas; Maass, Danielle [UNIFESP]; Souza, Antônio Augusto Ulson de; Souza, Selene Maria de Arruda Guelli Ulson de; http://lattes.cnpq.br/3431482044015696This work reports surfactin production by B. subtilis ATCC 6051 in a stirred tank bioreactor, where trub was used as a carbon source. Trub is a residue from the brewing industry mainly composed of high-molar-mass proteins and reducing sugars, being a sustainable and low-cost substrate for bioprocess. Despite this, Trub has been little explored as a raw material in bioprocesses. Aiming to evaluate important factors in scale-up process, the impact of oxygen transfer coefficient (KLa) concerning volumetric productivity, and the effect of agitation (150–300 rpm) and aeration (0.5–1.5 vvm) on biosurfactant production by a Full Factorial design were evaluated. Only agitation presented a significant effect on surfactin concentration (SF), where SF was described by a linear regression model (R2 = 0.99). The biosurfactant showed high stability in relation to variations in temperature and pH. In addition, the foam collecting was an efficient method in recovering and enrichment of the product.
- ItemAcesso aberto (Open Access)A low‑cost brewery waste as a carbon source in bio‑surfactant production(Dirk Weuster-Botz, 2021-06-22) Corrêa Nazareth, Talita; Planas Zanutto, Conrado; Maass, Danielle [UNIFESP]; Ulson de Souza, Antônio Augusto; Guelli Ulson de Souza, Selene Maria de Arruda; http://lattes.cnpq.br/3431482044015696This work aims to produce bio-surfactant using a brewery waste (trub) as a strategy to reduce production costs related to the substrate, as well as to provide an eco-friendly destination for this residue. Trub is obtained during the boiling of the wort, being mainly composed of proteins and reducing sugars. To evaluate important process parameters on bio-surfactant production, a full factorial design (2^4) was elaborated, having agitation rate and concentrations of trub, yeast extract, and peptone as independent variables. The highest bio-surfactant concentration achieved was 100.76 mg L−1, where FTIR and Maldi-ToF-MS confirmed functional groups characteristic of peptides and isomers of surfactin in the biosurfactant extract. Trub, agitation and yeast extract showed statistically significant effects on the response variable (surface tension), where an increase in the agitation rate and in the concentration of yeast extract demonstrated a positive impact on the production of bio-surfactant.
- ItemAcesso aberto (Open Access)The use of low-cost brewery waste product for the production of surfactin as a natural microbial biocide(Elsevier, 2020-10-07) Nazareth, Talita Corrêa; Zanutto, Conrado Planas; Tripathi, Lakshmi; Juma, Abdulaziz; Maass, Danielle [UNIFESP]; Souza, Antônio Augusto Ulson de; Souza, Selene Maria de Arruda Guelli Ulson de; http://lattes.cnpq.br/3431482044015696Surfactin has potential as next generation antibiofilm agent to combat antimicrobial resistance against emerging pathogens. However, the widespread industrial applications of surfactin is hampered by its high production cost. In this work, surfactin was produced from Bacillus subtilis using a low-cost brewery waste as a carbon source. The strain produced 210.11 mg L-1 after 28 h. The antimicrobial activity was observed against all tested strains, achieving complete inhibition for Pseudomonas aeruginosa, at 500 mg mL-1. A growth log reduction of 3.91 was achieved for P. aeruginosa while, Staphylococcus aureus and Staphylococcus epidermidis showed between 1 and 2 log reductions. In the anti-biofilm assays against P. aeruginosa, the co-incubation, anti-adhesive and disruption showed inhibition, where the greatest inhibition was observed in the co-incubation assay (79.80%). This study provides evidence that surfactin produced from a low-cost substrate can be a promising biocide due to its antimicrobial and anti-biofilm abilities against pathogens.