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1.
Chem Biol Interact ; 317: 108962, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31982400

RESUMO

Quaternary ammonium compounds (e.g., benzalkonium chloride (BAC) and cetylpyridinium chloride (CPC)) constitute a group of cationic surfactants are widely used for personal hygiene and medical care despite the potential pulmonary toxicity. To examine whether BAC and CPC aerosols deposited in the alveolar region alter pulmonary function, we studied the effects on pulmonary surfactant using two-step in vitro models; cytotoxicity using A549 alveolar epithelial cell and changes in surface activity of the pulmonary surfactant monolayer using both Surfacten® and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Cell viability was decreased with BAC and CPC dose-dependently. A comparison of cytotoxicity among BAC homologues with different length of alkyl chain showed that C16-BAC, which has the longest alkyl chain, was more cytotoxic than C12- or C14-BAC. Caspase-3/7 activity and cleaved form of caspase-3 and PARP were increased in BAC- and CPC-exposed cells. The elevated caspase-3/7 activity and their cleaved active forms were abolished by caspase-3-inhibitor. Furthermore, we examined the features of the surface pressure/trough area (π-A) isotherm by the Langmuir-Wilhelmy method and atomic force microscopy (AFM) images of lipid monolayers on a subphase containing BAC, CPC, or pyridinium chloride (PC, as a control). The π-A isotherms showed that addition of BAC or CPC yielded dose-dependent increases in surface pressure without compression, indicating that BAC and CPC expand the isotherm to larger areas at lower pressure. The collapse pressure diminished with increasing concentration of CPC. Topographic images indicated that BAC and CPC resulted in smaller condensed lipid domains compared to the control. Conversely, PC without hydrocarbon tail group, showed no cytotoxicity and did not change the isotherms and AFM images. These results indicate that BAC and CPC cause cell death via caspase-3-dependent apoptotic pathway in A549 cells and alter the alveolar surfactant activity. These effects can be attributed to the long alkyl chain of BAC and CPC.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Benzalcônio/farmacologia , Cetilpiridínio/farmacologia , Células Epiteliais/efeitos dos fármacos , Pulmão/citologia , Mucosa Respiratória/citologia , Células A549 , Compostos de Benzalcônio/química , Sobrevivência Celular/efeitos dos fármacos , Cetilpiridínio/química , Humanos , Tensoativos/metabolismo
2.
J Basic Microbiol ; 60(1): 14-21, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31696960

RESUMO

Gordoniae are one of the most promising hydrocarbon-oxidizing actinobacteria. Here we present the genome sequence analysis of thermotolerant strain Gordonia sp. 1D isolated from oil-refinery soil. It is capable of alkane consumption and biosurfactant production at temperatures of up to 50°C. Gordonia sp. 1D demonstrates maximum biosurfactant production when grown on hexadecane, and at 40°C it was slightly higher than at 27°C: 35 and 39 mN/m, respectively. For the first time, it was experimentally confirmed that the carbohydrate component of extracellular biosurfactants produced by strain 1D is trehalose. In addition, genes for the production of trehalose lipid biosurfactants were identified. The genetic determinants for two different pathways for trehalose synthesis were found. The strain carries genes otsA and otsB involved in de novo trehalose biosynthesis. Moreover, the genes treY and treZ responsible for trehalose biosynthesis from maltooligosaccharides and starch or glycogen were identified.


Assuntos
Genoma Bacteriano/genética , Gordonia (Bactéria)/genética , Gordonia (Bactéria)/metabolismo , Trealose/metabolismo , Genes Bacterianos , Glicolipídeos/química , Glicolipídeos/metabolismo , Gordonia (Bactéria)/classificação , Hidrocarbonetos/metabolismo , Petróleo/microbiologia , Filogenia , Microbiologia do Solo , Tensoativos/química , Tensoativos/metabolismo , Temperatura Ambiente
3.
Chemosphere ; 238: 124655, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472344

RESUMO

The effectiveness of nitrate-mediated souring control highly depends on the interactions of sulfate reducing bacteria (SRB) and nitrate reducing bacteria (NRB). Biosurfactants produced by natural NRB are promising bio-agents for enhancing NRB competence towards SRB. However, the function of NRB-produced biosurfactants in NRB-SRB interactions remains unexplored due to the rarely successful isolation of natural biosurfactant-producing NRB. Hereby, biosurfactant-aided inhibitory control of SRB strain Desulfomicrobium escambiense ATCC 51164 by biosurfactant-producing NRB strain Pseudomonas stutzeri CX3, reported in our previous work, was investigated. Under non-sour conditions, insufficient nitrate injection resulted in limited SRB inhibition. Phospholipid fatty acid (PLFA) biomarkers traced the overall bacterial responses. Compositional PLFA patterns revealed biosurfactant addition benefitted both SRB and NRB towards stressful conditions. Under sour conditions, nitrite oxidation of sulfide proved to be the primary mechanism for sulfide removal. The subsequent elevation of redox potential and pH inhibited SRB activities. NRB-produced biosurfactants significantly enhanced SRB inhibition by NRB through more efficient sulfide removal and effective duration of nitrate in the microcosms. Biosurfactants specially produced by the NRB strain are for the first time reported to significantly strengthen SRB inhibition by NRB via reduced nitrate usage and prolonged effective duration of nitrate, which has encouraging potential in nitrate-dependent souring control.


Assuntos
Bactérias/isolamento & purificação , Desulfovibrio/metabolismo , Nitratos/metabolismo , Sulfetos/isolamento & purificação , Tensoativos/metabolismo , Bactérias/metabolismo , Ácidos Graxos/análise , Oxirredução
4.
World J Microbiol Biotechnol ; 35(10): 155, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31576428

RESUMO

Biosurfactants are amphiphilic molecules produced by a variety of microorganisms, including bacteria, yeast and filamentous fungi. Unlike chemically synthesized surfactants, biosurfactants present advantages, such as biodegradability, low toxicity, high selectivity and activity under extreme temperature, pH and salinity conditions, as well as a low critical micelle concentration. Moreover, they can be produced from agro-industrial waste and renewable sources. Their structural diversity and functional properties mean that they have potential applications in various industrial processes as wetting agents, dispersants, emulsifiers, foaming agents, food additives and detergents, as well as in the field of environmental biotechnology. However, opportunities for their commercialization have been limited due to the low yields obtained in the fermentation processes involved in their production as well as the use of refined raw materials, which means higher cost in production. In an attempt to solve these limitations on the commercialization of biosurfactants, various research groups have focused on testing the use of inexpensive alternative sources, such as agro-industrial waste, as substrates for the production of different biosurfactants. In addition to enabling the economical production of biosurfactants, the use of such waste aims to reduce the accumulation of compounds that cause environmental damage. This review shows advances in biosurfactant production carried out using different waste materials or by-products from agro-industrial activities.


Assuntos
Bactérias/metabolismo , Resíduos Industriais/análise , Tensoativos/metabolismo , Leveduras/metabolismo , Bactérias/genética , Biodegradação Ambiental , Biotecnologia , Fermentação , Leveduras/genética
5.
Appl Microbiol Biotechnol ; 103(21-22): 8647-8656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31515599

RESUMO

In 1968, Arima et al. discovered the heptapeptide, known as surfactin, which belongs to a family of lipopeptides. Known for its ability to reduce surface tension, it also has biological activities such as antimicrobial and antiviral. Its non-ribosomal synthesis mechanism was later discovered (1991). Lipopeptides represent an important class of surfactants, which can be applied in many industrial sectors such as food, pharmaceutical, agrochemicals, detergents, and cleaning products. Currently, 75% of the surfactants used in the various industrial sectors are from the petrochemical industry. Nevertheless, there are global current demands (green chemistry concept) to replace the petrochemical products with environmentally friendly products, such as surfactants by biosurfactants. The production biosurfactants still are costly. Thus, an alternative to reduce the production costs is using agro-industrial waste as a culture medium associated with an efficient and scalable purification process. This review puts a light on the agro-industrial residues used to produce surfactin and the techniques used for its recovery.


Assuntos
Microbiologia Industrial/economia , Lipopeptídeos/economia , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/economia , Peptídeos Cíclicos/metabolismo , Tensoativos/economia , Bactérias/genética , Bactérias/metabolismo , História do Século XX , História do Século XXI , Microbiologia Industrial/história , Microbiologia Industrial/métodos , Lipopeptídeos/genética , Lipopeptídeos/história , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/história , Tensoativos/história , Tensoativos/metabolismo
6.
Microbiol Res ; 229: 126329, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31518853

RESUMO

The genus Serratia is a predominantly unexplored source of antimicrobial secondary metabolites. The aim of the current study was thus to isolate and evaluate the antimicrobial properties of biosurfactants produced by Serratia species. Forty-nine (n = 34 pigmented; n = 15 non-pigmented) biosurfactant producing Serratia strains were isolated from environmental sources and selected isolates (n = 11 pigmented; n = 11 non-pigmented) were identified as Serratia marcescens using molecular typing. The swrW gene (serrawettin W1 synthetase) was detected in all the screened pigmented strains and one non-pigmented strain and primers were designed for the detection of the swrA gene (non-ribosomal serrawettin W2 synthetase), which was detected in nine non-pigmented strains. Crude extracts obtained from S. marcescens P1, NP1 and NP2 were chemically characterised using ultra-performance liquid chromatography coupled to electrospray ionisation mass spectrometry (UPLC-ESI-MS), which revealed that P1 produced serrawettin W1 homologues and prodigiosin, while NP1 produced serrawettin W1 homologues and glucosamine derivative A. In contrast, serrawettin W2 analogues were predominantly identified in the crude extract obtained from S. marcescens NP2. Both P1 and NP1 crude extracts displayed broad-spectrum antimicrobial activity against clinical, food and environmental pathogens, such as multidrug-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and Cryptococcus neoformans. In contrast, the NP2 crude extract displayed antibacterial activity against a limited range of pathogenic and opportunistic pathogens. The serrawettin W1 homologues, in combination with prodigiosin and glucosamine derivatives, produced by pigmented and non-pigmented S. marcescens strains, could thus potentially be employed as broad-spectrum therapeutic agents against multidrug-resistant bacterial and fungal pathogens.


Assuntos
Antibacterianos/farmacologia , Depsipeptídeos/farmacologia , Lipoproteínas/farmacologia , Peptídeos Cíclicos/farmacologia , Prodigiosina/farmacologia , Serratia marcescens/química , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Depsipeptídeos/química , Depsipeptídeos/metabolismo , Lipoproteínas/química , Lipoproteínas/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Prodigiosina/química , Prodigiosina/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Metabolismo Secundário , Serratia marcescens/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Tensoativos/farmacologia
7.
Future Microbiol ; 14: 1133-1146, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31512521

RESUMO

Aim: This study aimed to evaluate the differences of biosurfactants produced by two Lactobacillus helveticus strains against the biofilm formation of Staphylococcus aureus in vitro and in vivo. Materials & methods: Scanning electron microscopy, Real time-quantitative PCR (RT-qPCR) and cell assay were used to analyze the inhibiting effect of biosurfactants against biofilm formation. Results & conclusion: Results showed that the biosurfactants have anti-adhesive and inhibiting effects on biofilm formation in vivo and in vitro. The biofilm-formative genes and autoinducer-2 signaling regulated these characteristics, and the biosurfactant L. helveticus 27170 is better than that of 27058. Host cell adhesion and invasion results indicated that the biosurfactants L. helveticus prevented the S. aureus invading the host cell, which may be a new strategy to eliminate biofilms.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Lactobacillus helveticus/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/farmacologia , Animais , Antibacterianos/metabolismo , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Células Cultivadas , Humanos , Queratinócitos/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Tensoativos/metabolismo
8.
Mol Biotechnol ; 61(11): 836-851, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31482467

RESUMO

Phosphopantetheinyl transferases are of tremendous enthusiasm inferable from their fundamental parts in activating polyketide, fatty acid, and non-ribosomal peptide synthetase enzymes and additionally an increasing number of biotechnological applications. The present study reports the identification of sfp gene from the Paenibacillus sp. D9, which encompasses 693 bp encoding a 230-amino acid protein with a molecular weight of 25.3 kDa. The amino acid sequence Paenibacillus sp. D9 Sfp revealed more than 90% sequence identity to other Sfp proteins from other Paenibacillus. The sfp gene was cloned and recovered efficiently using affinity chromatography with maximal specific phosphopantetheinyl transferase activity at an optimal pH of 8.0 and temperature of 30 °C. The enzyme also exhibited stability under a wide-ranging pH and temperature. The presence of Zn2+, Cu2+, and Fe2+ ions improved the enzymatic activity, while other metals such as Ni2+, Co2+, and Mg2+ had inhibitory effects. The introduction of EDTA also displayed no inhibition. Kinetic parameters were obtained having values of 4.52 mg/mL, 35.33 U/mg, 3.64 s-1, and 0.104 mM-1 s-1 for Km, Vmax, kcat, and kcat/Km, respectively. The biosurfactant synthesized by the recombinant BioSp was found to be surface active, reducing the surface tension to 33.7 mN/m on the glucose substrate after 5 days of incubation at 37 °C. The recombinant Escherichia coli strain also exhibited an improvement in biosurfactant yield (1.11 g/L) when contrasted with 0.52 g/L from Paenibacillus sp. D9. High esterase activity of 2.55 IU/mL using p-nitrophenyl acetate was observed on the recombinant strain, as the protein connected with the release of the biosurfactant was observed to be an esterase. The characteristics of improved biosurfactant and esterase synthesis by hyper-producing recombinant strain possess numerous values from biotechnology standpoint.


Assuntos
Proteínas de Bactérias/metabolismo , Lipopeptídeos/biossíntese , Paenibacillus/enzimologia , Tensoativos/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Sequência de Aminoácidos/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Biotecnologia , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Esterases/metabolismo , Cinética , Metais Pesados/metabolismo , Peptídeo Sintases/metabolismo , Filogenia , Tensoativos/química , Transferases (Outros Grupos de Fosfato Substituídos)/química , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/isolamento & purificação
9.
J Microbiol Biotechnol ; 29(11): 1749-1759, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31474100

RESUMO

Aspergillus ochraceus biofilm, developed on an inert support, can produce tannase in Khanna medium containing 1.5% (w/v) tannic acid as the carbon source, at an initial pH of 5.0, for 72 h at 28 °C. Addition of 0.1% yeast extract increased enzyme production. The enzyme in the crude filtrate exhibited the highest activity at 30 °C and pH 6.0. At 50 °C, the half-life was 60 min and 260 min at pH 6.0. In general, addition of detergents and surfactants did not affect tannase activity significantly. Tannase has potential applications in various biotechnological processes such as the production of propyl gallate and in the treatment of tannin-rich effluents. The content of tannins and total phenolic compounds in effluents from leather treatment was reduced by 56-83% and 47-64%, respectively, after 2 h of enzyme treatment. The content of tannins and total phenolic compounds in the sorghum flour treated for 120 h with tannase were reduced by 61% and 17%, respectively. Interestingly, the same A. ochraceus biofilm was able to produce tannase for three sequential fermentative process. In conclusion, fungal biofilm is an interesting alternative to produce high levels of tannase with biotechnological potential to be applied in different industrial sectors.


Assuntos
Aspergillus ochraceus/enzimologia , Biofilmes , Hidrolases de Éster Carboxílico/metabolismo , Proteínas Fúngicas/metabolismo , Aspergillus ochraceus/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Meios de Cultura/química , Fermentação , Concentração de Íons de Hidrogênio , Fenóis/metabolismo , Galato de Propila/metabolismo , Sorghum/química , Tensoativos/metabolismo , Taninos/metabolismo , Temperatura Ambiente , Poluentes da Água/metabolismo
10.
Ecotoxicol Environ Saf ; 184: 109607, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31505408

RESUMO

Petroleum hydrocarbons, oil, heavy metals pollution is becoming additional severe problem due to the growing call for crude oil and crude oil products related products in several fields of application. Such pollution have fascinated much considerations and attractions as it leads to ecological damages in both marines, aquatic and terrestrial ecosystems. Thus, different techniques including chemical surfactants and complex technologies have been proposed for their clean up from the environment, which in turn has detrimental effects on the environment. As of late, biosurfactant compounds have added much deliberation since they are considered as a reasonable option and eco-accommodating materials for remediation technology. The present society is confronting a few difficulties of usage, authorizing ecological protection and environmental change for the next generations. Biosurfactants hold the special property of minimizing and reducing the interfacial tension of liquids. Such features endure biosurfactants to afford a major part in emulsification, de-emulsification, biodegradability, foam formation, washing performance, surface activity, and detergent formulation, which have potential applications in the diverse industrial set-up. Conversations on cost-effective technologies, renewable materials, novel synthesis, downstream, upstream, emerging characterization techniques, molecular, and genetical engineering are substantial to produce biosurfactant of quality and quantity. Therefore, greater attention is being paid to biosurfactant production by identifying their environmental, and biotechnological applications. Be that as it may, the extravagant cost drew in with biosurfactants biotechnological synthesis and recovery can hamper their application in those areas. Notwithstanding these costs, biosurfactants can be used as these parts shows outstandingly high benefits that can at present beat the expenses incurred in the initial purification and downstream processes. Biosurfactant production by microorganisms is relatively considered one of the crucial know-how for improvement, growth, advancement, and environmental sustainability of the 21st century. There is a developing conversation around environmental safety and the significant role that biosurfactants will progressively play soon, for instance, the use of renewable by-products as substrates, potential reduction, re-use and recycling of waste and waste products. The review confers the usefulness of biosurfactants in the removal of environmental contaminants and, consequently, expanding environmental safety and drive towards greener technology.


Assuntos
Biodegradação Ambiental , Tensoativos/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Química Verde/tendências , Microbiologia Industrial/tendências , Propriedades de Superfície , Tensoativos/química , Tensoativos/toxicidade
11.
Colloids Surf B Biointerfaces ; 182: 110372, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369953

RESUMO

Biosurfactant producing hypethermophilic microorganisms are essentially required for Microbial Enhanced Oil Recovery (MEOR) from high temperature oil reservoirs (above 90 °C). In the present study, biosurfactant producing Clostridium sp. N-4, optimally growing at 96 °C was isolated from a high temperature oil reservoir. Effect of pH, temperature and salinity on production and activity of N-4 biosurfactant was investigated. Biosurfactant produced by N-4 was partially purified by acid precipitation, characterized using FT-IR spectroscopy; and evaluated for its ability to enhance oil recovery in sand pack studies. The strain N-4 produced biosurfactant over a wide range of pH (5.0-9.0) and salinity (0-13%) at high temperature (80-100 °C) and optimally at pH 7, 96 °C and 4% salinity. N-4 biosurfactant was active at 37-101 °C; pH, 5-10 and salinity of 0-12 % (w/v). N-4 biosurfactant, characterized as glycoprotein reduced the surface tension of water by 32 ± 0.4 mN/m at critical micelle concentration of 100 µg/ml. N-4 biosurfactant mobilized 17.15% of residual oil saturation in sand pack studies. Similarly, the strain N-4 also recovered 36.92% of the residual oil in sand pack studies under the conditions mimicking the environment of depleted high temperature oil reservoir. Thus, the biosurfactant producing Clostridium sp. N-4 was identified as a suitable agent for enhanced oil recovery from high temperature oil reservoirs.


Assuntos
Proteínas de Bactérias/metabolismo , Clostridium/metabolismo , Glicoproteínas/metabolismo , Temperatura Alta , Petróleo/metabolismo , Tensoativos/metabolismo , Proteínas de Bactérias/química , Glicoproteínas/química , Concentração de Íons de Hidrogênio , Campos de Petróleo e Gás/química , Salinidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química
12.
Environ Monit Assess ; 191(9): 531, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375926

RESUMO

Microbially produced biosurfactants are fast catching up due to their environment-friendly approach over chemical surfactants. But their commercial production is restricted due to poor economy of the production process which could be improved by using high yielding microbial strains and optimizing the process parameters. The present research was directed to optimize the biosurfactant production monitored in terms of oil displacement and emulsification (E24) index, using a promising yeast Meyerozyma guilliermondii YK32. Maximum oil displacement equaling 7.5 cm was obtained with olive oil at 8% (v/v) concentration as carbon source under shaking conditions (150 rpm). Diesel being a complex hydrocarbon was not utilized easily by yeast and showed poor biosurfactant production. Yeast extract at 1.5% (w/v) concentration yielded maximum biosurfactant as evident from maximum oil displacement and E24 index equal to 8.1 cm and 52.6%, respectively. Sodium chloride at the rate of 3% (w/v) supported maximum oil displacement (8.8 cm) using the production broth containing optimized carbon and nitrogen sources. Any increase beyond this level negatively influenced the biosurfactant production. The yield was at its maximum at 30 °C as a shift in temperature either to 35 °C or 25 °C decreased the oil displacement from 8.8 to 5.2 or 7.6 cm, respectively. At 40 °C, oil displacement was decreased to 2.5 cm. Biosurfactant production appeared to be sensitive to varying pH as evident from the E24 index as high as 67.3% at pH 6.0 as compared with 60.2%, 60.1%, and 52.4% at pH 5.0, 5.5, and 7.0, respectively. Yeast biomass yield equivalent to 10.3 g/L and 8.3 g/L was recorded at pH 6 and 7, respectively, during the production process. Elimination of shaking reduced the E24 index from 67.3 to 34.8% under optimized conditions.


Assuntos
Monitoramento Ambiental/métodos , Saccharomycetales/metabolismo , Tensoativos/metabolismo , Biomassa , Carbono/metabolismo , Hidrocarbonetos/metabolismo , Nitrogênio/metabolismo , Saccharomycetales/crescimento & desenvolvimento , Temperatura Ambiente
13.
Colloids Surf B Biointerfaces ; 182: 110399, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31377609

RESUMO

The interaction between calf thymus DNA, ctDNA, and a series of oligomeric surfactants derived from N-benzyl-N,N-dimethyl-N-(1-dodecyl)ammonium chloride is investigated. The influence of the surfactants' degree of oligomerization (2, 3 and 4) on the ctDNA/surfactant interaction is studied, as well as the effect of the structure of the spacer group linking the individual surfactant fragments. In particular, the effect of the distance between the positive charges and the hydrophobic chains within the oligomers on these interactions was examined, by using the three positional isomers (i.e., ortho-, meta-, and para-) with the rigid xylidene moiety as spacer. Results show that the dimeric ("gemini") surfactants are much more efficient in the inversion of the nucleic acid charge than the single-chained (monomeric) surfactant. Whereas the ortho - isomer causes a partial condensation, the meta - and para - isomers can completely condense ctDNA. The meta - and para - isomers of the trimeric surfactants can also completely condense the polynucleotide. In contrast, the tetrameric surfactant investigated does not change the morphology of the nucleic acid from an elongated coil into a compacted form, in spite of effectively inverting the nucleic acid's charge in their complex. Accordingly, the capacity for ctDNA compaction of oligomeric surfactants is not simply correlated to their degree of oligomerization, but depends on a complex balance of the number and relative distance of cationic charges and/or hydrophobic tails in the surfactants for effectively interacting with the nucleic acid to form the appropriate complex. This information will help to design more effective cationic surfactants as non-viral vectors for gene therapy.


Assuntos
DNA/química , Substâncias Macromoleculares/química , Polimerização , Polímeros/química , Tensoativos/química , Cátions/química , Dicroísmo Circular , DNA/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Substâncias Macromoleculares/metabolismo , Microscopia de Força Atômica , Estrutura Molecular , Polímeros/metabolismo , Espectrofotometria , Eletricidade Estática , Tensoativos/metabolismo
14.
Ecotoxicol Environ Saf ; 183: 109478, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31374383

RESUMO

An increasing concern for Gemini surfactants (GS) based on the class alkanediyl-α-ω-bis (dimethylalkylammonium bromide) has been reported in ecotoxicological researchbecause of their estrogenic properties causing an alarm to aquatic life. In this study, we analyzed the toxic effects of the synthesized GS (12-2-12 and 16-2-16) leading to histological changes in fingerlings (kidney, gills, intestine, and liver) of Cirrhinusmrigala. Damage in the tissues in correlation with their normal architecture was observed microscopically and was manifold. The tissue-specific morphological alterations associated with somatic index (MAV- mean alteration value) were used as biomarker. The present study also highlighted the changes in the antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT). In order to estimate the sub-lethal toxic properties of GS, the genotoxicity and cytotoxicity of GS were evaluated using blood smear assay and HeLa cell line respectively. Results of the study exhibited potential biotoxicity where GS with the highest hydrophobicity showed upper most toxicity level under different exposure time, while GS with less hydrophobic features exhibited least stressful regimeto the tested animal. The prepared GS were also examined for their biodegradability following the die-away method. The theoretical approach estimates the structural information by computational simulation.


Assuntos
Cyprinidae , Estresse Oxidativo , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Simulação por Computador , Cyprinidae/anatomia & histologia , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/patologia , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Intestinos/efeitos dos fármacos , Intestinos/patologia , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Especificidade de Órgãos , Superóxido Dismutase/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
15.
Curr Microbiol ; 76(11): 1320-1329, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31432210

RESUMO

Pseudomonas putida E41 isolated from root interior of Sida hermaphrodita (grown on a field contaminated with heavy metals) showed high biosurfactant activity. In this paper, we describe data from mass spectrometry and genome analysis, to improve our understanding on the phenotypic properties of the strain. Supernatant derived from P. putida E41 liquid culture exhibited a strong decrease in the surface tension accompanied by the ability for emulsion stabilization. We identified extracellular lipopeptides, putisolvin I and II expression but did not detect rhamnolipids. Their presence was confirmed by matrix-assisted laser desorption and ionization (MALDI) TOF/TOF technique. Moreover, ten phospholipids (mainly phosphatidylethanolamines PE 33:1 and PE 32:1) which were excreted by vesicles were also detected. In contrast the bacterial cell pellet was dominated by phosphatidylglycerols (PGs), which were almost absent in the supernatant. It seems that the composition of extracellular (secreted to the environment) and cellular lipids in this strain differs. Long-read sequencing and complete genome reconstruction allowed the identification of a complete putisolvin biosynthesis pathway. In the genome of P. putida E41 were also found all genes involved in glycerophospholipid biosynthesis, and they are likely responsible for the production of detected phospholipids. Overall this is the first report describing the expression of extracellular lipopeptides (identified as putisolvins) and phospholipids by a P. putida strain, which might be explained by the need to adapt to the highly contaminated environment.


Assuntos
Metais Pesados/metabolismo , Pseudomonas putida/metabolismo , Sida (Planta)/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Tensoativos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Pseudomonas putida/química , Pseudomonas putida/genética , Pseudomonas putida/isolamento & purificação , Sida (Planta)/metabolismo , Sida (Planta)/microbiologia , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Ultrason Sonochem ; 59: 104724, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421618

RESUMO

Due to their nonpathogenic status, biosurfactants produced by Lactobacillus strains have been shown to have potential applicability in several industrial sectors, particularly food and pharmaceutical industries. However, products with high efficiency are needed to fulfill the demand for these biosurfactants. Therefore, the present study investigated kinetic parameters, biomass and biosurfactant production of Lactobacillus plantarum ATCC 8014 applying standard MRS and modified MRS (supplemented standard MRS by nitrogen and carbon sources) culture medium under various ultrasonic frequencies of 20, 25, 35, 45, 130 and 950 kHz to obtain more efficient conditions. The optimum conditions were found when using the modified MRS treated by the frequency of 25 kHz (the power of 7.4 W) for 30 min, which led to a significant effect on the growth rate (µmax, h-1) rather than control. Furthermore, this condition caused the highest population (10.07 ±â€¯0.1 log CFU/mL) and biomass concentration (4.33 ±â€¯0.06 g/L), and lowest surface tension (39.26 ±â€¯0.5 mN/m), leading to higher biosurfactant production. Hence, given the results of the present study, it can be established that controlled ultrasound exposure and supplementation of culture media using the main growth factors can intensify the microbial activity and the productivity of biological processes.


Assuntos
Biotecnologia/métodos , Lactobacillus plantarum/metabolismo , Tensoativos/metabolismo , Ondas Ultrassônicas , Biomassa , Cinética , Lactobacillus plantarum/fisiologia , Viabilidade Microbiana
17.
Biomater Sci ; 7(9): 3812-3820, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31264671

RESUMO

Self-assembled cationic micelles are an attractive platform for binding biologically-relevant polyanions such as heparin. This has potential applications in coagulation control, where a synthetic heparin rescue agent could be a useful replacement for protamine, which is in current clinical use. However, micelles can have low stability in human serum and unacceptable toxicity profiles. This paper reports the optimisation of self-assembled multivalent (SAMul) arrays of amphiphilic ligands to bind heparin in competitive conditions. Specifically, modification of the hydrophobic unit kinetically stabilises the self-assembled nanostructures, preventing loss of binding ability in the presence of human serum - cholesterol hydrophobic units significantly outperform systems with a simple aliphatic chain. It is demonstrated that serum albumin disrupts the binding thermodynamics of the latter system. Molecular simulation shows aliphatic lipids can more easily be removed from the self-assembled nanostructures than the cholesterol analogues. This agrees with the experimental observation that the cholesterol-based systems undergo slower disassembly and subsequent degradation via ester hydrolysis. Furthermore, by stabilising the SAMul nanostructures, toxicity towards human cells is decreased and biocompatibility enhanced, with markedly improved survival of human hepatoblastoma cells in an MTT assay.


Assuntos
Colesterol/sangue , Heparina/sangue , Tensoativos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Colesterol/farmacologia , Heparina/química , Heparina/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligantes , Micelas , Estrutura Molecular , Nanoestruturas/química , Tensoativos/química , Tensoativos/farmacologia , Termodinâmica
18.
Molecules ; 24(14)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323769

RESUMO

High production costs of biosurfactants are mainly caused by the usage of the expensive substrate and long fermentation period which undermines their potential in bioremediation processes, food, and cosmetic industries even though they, owing to the biodegradability, lower toxicity, and raise specificity traits. One way to circumvent this is to improvise the formulation of biosurfactant-production medium by using cheaper substrate. A culture medium utilizing palm fatty acid distillate (PFAD), a palm oil refinery by-product, was first developed through one-factor-at-a-time (OFAT) technique and further refined by means of the statistical design method of factorial and response surface modeling to enhance the biosurfactant production from Pseudomonas sp. LM19. The results shows that, the optimized culture medium containing: 1.148% (v/v) PFAD; 4.054 g/L KH2PO4; 1.30 g/L yeast extract; 0.023 g/L sodium-EDTA; 1.057 g/L MgSO4·7H2O; 0.75 g/L K2HPO4; 0.20 g/L CaCl2·2H2O; 0.080 g/L FeCl3·6H2O gave the maximum biosurfactant productivity. This study demonstrated that the cell concentration and biosurfactant productivity could reach up to 8.5 × 109 CFU/mL and 0.346 g/L/day, respectively after seven days of growth, which were comparable to the values predicted by an RSM regression model, i.e., 8.4 × 109 CFU/mL and 0.347 g/L/day, respectively. Eleven rhamnolipid congeners were detected, in which dirhamnolipid accounted for 58% and monorhamnolipid was 42%. All in all, manipulation of palm oil by-products proved to be a feasible substrate for increasing the biosurfactant production about 3.55-fold as shown in this study.


Assuntos
Meios de Cultura , Ácidos Graxos/química , Óleo de Palmeira/química , Pseudomonas/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Destilação , Fermentação , Nitrogênio/metabolismo , Tensoativos/análise
19.
Molecules ; 24(14)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323813

RESUMO

Heavy metals from industrial effluents and sewage contribute to serious water pollution in most developing countries. The constant penetration and contamination of heavy metals into natural water sources may substantially raise the chances of human exposure to these metals through ingestion, inhalation, or skin contact, which could lead to liver damage, cancer, and other severe conditions in the long term. Biosurfactant as an efficient biological surface-active agent may provide an alternative solution for the removal of heavy metals from industrial wastes. Biosurfactants exhibit the properties of reducing surface and interfacial tension, stabilizing emulsions, promoting foaming, high selectivity, and specific activity at extreme temperatures, pH, and salinity, and the ability to be synthesized from renewable resources. This study aimed to produce biosurfactant from renewable feedstock, which is used cooking oil (UCO), by a local isolate, namely Bacillus sp. HIP3 for heavy metals removal. Bacillus sp. HIP3 is a Gram-positive isolate that gave the highest oil displacement area with the lowest surface tension, of 38 mN/m, after 7 days of culturing in mineral salt medium and 2% (v/v) UCO at a temperature of 30 °C and under agitation at 200 rpm. An extraction method, using chloroform:methanol (2:1) as the solvents, gave the highest biosurfactant yield, which was 9.5 g/L. High performance liquid chromatography (HPLC) analysis confirmed that the biosurfactant produced by Bacillus sp. HIP3 consists of a lipopeptide similar to standard surfactin. The biosurfactant was capable of removing 13.57%, 12.71%, 2.91%, 1.68%, and 0.7% of copper, lead, zinc, chromium, and cadmium, respectively, from artificially contaminated water, highlighting its potential for bioremediation.


Assuntos
Bacillus/metabolismo , Biodegradação Ambiental , Gorduras Insaturadas na Dieta/metabolismo , Metais Pesados/química , Tensoativos/química , Tensoativos/metabolismo , Adsorção , Bacillus/classificação , Bacillus/genética , Proteínas de Bactérias/genética , Filogenia , Tensoativos/isolamento & purificação
20.
J Appl Microbiol ; 127(5): 1442-1453, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31325223

RESUMO

AIMS: The aim of this study was to elucidate the chemical properties and applications of trehalose lipids produced by Rhodococcus qingshengii strain FF and optimize its production yield. METHODS AND RESULTS: Strain FF was identified as R. qingshengii. It was observed to produce biosurfactants in the presence of n-hexadecane. The biosurfactants were identified as the mixture of trehalose triesters and trehalose tetraesters, mainly consisting of TrehC12 C3 C6 C12 :10, TrehC11 C8 C6 :6, TrehC11 C6 C4 :5 and TrehC6 C4 C6 :5 based on the analysis of thin layer chromatography, Fourier transform infrared and flight tandem mass spectrometry. The best carbon source and nitrogen source for producing trehalose lipids was the mixture of n-hexadecane and oleic acid (m : m = 1 : 1) and the organic nitrogen, urea. Under this condition, the production of trehalose lipids could reach 7·97 g l-1 . The crude trehalose lipids showed extremely high surface-active properties and were proven to promote the degradation of naphthalene. CONCLUSIONS: The trehalose lipids produced by R. qingshengii strain FF exhibited high surfactant activity under various conditions and were proven to promote the degradation of naphthalene. SIGNIFICANCE AND IMPACT OF THE STUDY: Rhodococcus qingshengii strain FF is a potential candidate for bioremediation. The trehalose lipids might be used as unique biosurfactants in cosmetic industries, biological formulations and other applications.


Assuntos
Lipídeos/química , Rhodococcus/metabolismo , Trealose/análise , Trealose/metabolismo , Alcanos/metabolismo , Cromatografia em Camada Delgada , Microbiologia Ambiental , Lipídeos/biossíntese , Filogenia , Rhodococcus/classificação , Rhodococcus/genética , Rhodococcus/isolamento & purificação , Tensoativos/química , Tensoativos/metabolismo , Espectrometria de Massas em Tandem , Águas Residuárias/microbiologia
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