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1.
Artigo em Inglês | MEDLINE | ID: mdl-38744689

RESUMO

Cosmetics have been extremely popular throughout history and continue to be so today. Cosmetic and personal care products, including toothpaste, shampoo, lotions, and makeup, are typically made with petroleum-based surfactants. Currently, there is an increasing demand to enhance the sustainability of surface-active compounds in dermal formulations. Biosurfactants, derived from living cells, are considered more environmentally friendly than synthetic surfactants. Thus, the use of biosurfactants is a promising strategy for formulating more environmentally friendly and sustainable dermal products. Biosurfactants have the potential to replace chemical surface-active agents in the cosmetic sector due to their multifunctional qualities, such as foaming, emulsifying, and skin-moisturizing activities.In this study, two glycolipopeptide biosurfactants derived from Lactiplantibacillus plantarum OL5 were used as stabilizing factors in oil-in-water emulsions in the presence of coconut oils. Both biosurfactants increased emulsion stability, particularly in the 1:3 ratio, dispersion, and droplet size. Moreover, the cytotoxicity of the two Lactiplantibacillus plantarum biosurfactants was assessed on B lymphocytes and MCF-7 cells. Overall, the results gathered herein are very promising for the development of new green cosmetic formulations.

2.
World J Microbiol Biotechnol ; 39(11): 308, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37715930

RESUMO

Microbial surfactants are natural amphiphilic compounds with high surface activities and emulsifying properties. Due to their structural diversity, low toxicity, biodegradability, and chemical stability in different conditions, these molecules are potential substitutes for chemical surfactants; their interest has grown significantly over the last decade. The current study focuses on the isolation, identification, and characterization of a lactic acid bacteria that produce two forms of biosurfactants. The OL5 strain was isolated from green olive fermentation and identified using MALDI/TOF and DNAr16S amplification. Emulsification activity and surface tension measurements were used to estimate biosurfactant production. The two biosurfactants derived from Lactiplantibacillus plantarum OL5 presented good emulsification powers in the presence of various oils. They were also shown to have the potential to reduce water surface tension from 69 mN/m to 34 mN/m and 37 mN/m within a critical micelle concentration (CMC) of 7 mg/ml and 1.8 mg/ml, respectively, for cell bound and extracellular biosurfactants. Thin layer chromatography (TLC) and FT-IR were used to analyze the composition of the two biosurfactants produced. the obtained data revealed that the two biomolecules consist of a mixture of carbohydrates, lipids and proteins. We demonstrated that they are two anionic biosurfactants with glycolipopeptide nature which are stable in extreme conditions of temperature, pH and salinity.


Assuntos
Lactobacillales , Olea , Espectroscopia de Infravermelho com Transformada de Fourier , Cromatografia em Camada Fina , Água
3.
Food Sci Biotechnol ; 32(11): 1595-1609, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37637836

RESUMO

Bacillus subtilis SPB1 derived biosurfactants (BioS) proved its bio-control activity against Agrobacterium tumefaciens using tomato plant. Almost 83% of disease symptoms triggered by Agrobacterium tumefaciens were reduced. Aiming potential application, we studied lipopeptide cost-effective production in both fermentations systems, namely the submerged fermentation (SmF) and the solid-state fermentation (SSF) as well as the use of Aleppo pine waste and confectionery effluent as cheap substrates. Optimization studies using Box-Behnken (BB) design followed by the analysis with response surface methodology were applied. When using an effluent/sea water ratio of 1, Aleppo pine waste of 14.08 g/L and an inoculum size of 0.2, a best production yield of 17.16 ± 0.91 mg/g was obtained for the SmF. While for the SSF, the best production yield of 27.59 ± 1.63 mg/g was achieved when the value of Aleppo pine waste, moisture, and inoculum size were, respectively, equal to 25 g, 75%, and 0.2. Hence, this work demonstrated the superiority of SSF over SmF.

4.
Water Sci Technol ; 87(7): 1764-1778, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37051796

RESUMO

The current work aims to optimize biological textile effluent treatment through the use of newly selected bacterial consortia composed of two strains: Citrobacter sedlakii RI11 and Aeromonas veronii GRI. We assessed the effect of SPB1 biosurfactant addition on color removal (CR). The process was optimized by a Box-Bhenken by examining the effect of pH, consortia density and biosurfactant value on treatment efficiency. Firstly, physicochemical analyses of the studied effluent revealed an alkaline pH along with a high content of suspended materials and large amounts of organic matter. Optimal CR and a chemical oxygen demand abatement of about 94 and 86% were obtained when treating the textile effluent at pH 5 with a total optical density of 0.4 and by incorporating 0.01% SPB1 biosurfactant. Additionally, an abolishment of phytotoxicity was registered after treatment optimization. The evaluations of the action mode of both selected bacteria during textile effluent treatment suggested the occurrence of biodegradation phenomena of dyes through enzymatic activities.


Assuntos
Corantes , Tensoativos , Tensoativos/química , Biodegradação Ambiental , Corantes/metabolismo , Bactérias/metabolismo , Têxteis , Indústria Têxtil
5.
Bioprocess Biosyst Eng ; 46(4): 555-563, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36645491

RESUMO

Biosurfactants stand for highly useful and promising compounds. They basically serve for a variety of applications in multiple industries and aspects of human life. Therefore, it is highly required to improve their production yield especially through the development of new and more efficient fermentation processes. In this aim, batch and fed-batch were studied and compared in terms of their effective biosurfactant production by Bacillus subtilis SPB1. Experiments of fed-batch fermentations were carried out through three different glucose feeding strategies, namely the pulsed, the constant Donespeed and the exponential feeding. The comparison between different fermentation processes revealed that fed-batch process proved to be a more efficient cultivation strategy than the batch process in terms of cell biomass, biosurfactant production and productivity. Among the three different feeding strategies, the exponential feeding process achieved the highest fermentation results of final biosurfactant concentration. The latter increased more than twofolds compared to batch fermentation.


Assuntos
Bacillus subtilis , Reatores Biológicos , Humanos , Fermentação , Glucose , Biomassa
6.
Water Sci Technol ; 86(5): 1083-1094, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36358047

RESUMO

In the present work, we demonstrated the potential use of newly identified lipopeptides produced by B. mojavensis BI2 along with palm waste flour for the bioremediation of heavy metals contaminated water. The enhancement of radish seeds germination was used to evaluate the treatment efficiency. Firstly, better enhancement in the order of 3.8, 2.52, 1.5 and 5 were recorded respectively for 200 mg/L copper, lead, cobalt and mercury with respective lipopeptide quantities of the order of 200, 300, 200 and 400 mg/L. When studying the sequestration of increasing heavy metals concentration, BI2 lipopeptide was effective. Secondly, a mixed bioprocess was evaluated using palm waste flour as heavy metals sequester and BI2 lipopeptides as improver. Optimal biosorption of lead, copper, cobalt and mercury were obtained with 10 g/l waste, 1,000 mg/l metal and 200 mg/l BI2 lipopeptide for 1 hour. The addition of 200 mg/l BI2 lipopeptide improves the efficiency of the treatment significantly.


Assuntos
Mercúrio , Metais Pesados , Lipopeptídeos , Água , Cobre/análise , Farinha , Metais Pesados/análise , Biodegradação Ambiental , Cobalto , Águas Residuárias
7.
Bioprocess Biosyst Eng ; 45(1): 31-44, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34807299

RESUMO

The present study summarizes the valorization of date flour by the production of lipopeptide biosurfactant (BioS) by Bacillus subtilis ZNI5 (MW091416). A Taguchi design permitted the formulation of a medium composed only of 6% date flour and 0.5% yeast extract within 2 days of incubation at 150 rpm with a maximal surface tension (ST) reduction of about 27.8 mN/m. The characterization of the lipopeptide shows a CMC value of about 400 mg/L with a minimal ST of 30 mN/m and an ability to disperse oil to about 80 mm at 800 mg/L. Having reduced phytotoxicity, the ZNI5 BioS and ZNI5 strain were assayed for Copper and Cobalt chelation and biosorption. The improvement of the germination index of radish seeds irrigated by the treated contaminated water showed the great potential application of ZNI5 lipopeptide in the bioremediation of heavy metals.


Assuntos
Biodegradação Ambiental , Quelantes/química , Farinha/análise , Lipopeptídeos/química , Metais Pesados/química , Tensoativos/química , Propriedades de Superfície
8.
Bioprocess Biosyst Eng ; 44(11): 2315-2330, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34241696

RESUMO

Lipopeptides biosurfactants (BioS) are natural surface-active compounds produced by a variety of microorganisms. They have great interest in environmental, biomedical and agro-industrial fields. However their large-scale application and production is limited by the cost of culture media and the low yield of production. Therefore, the improvement of the production yields and the development of efficient and cost-effective bioprocess became of a great interest. In this aim, we applied the response surface method to optimize an economic BioS production by a newly isolated strain Bacillus mojavensis BI2 on date Juice called "Luegmi" as unique carbon and nitrogen source. Using a Box-Bhenken design, we studied the effect of three independent variables on lipopeptide production; Leugmi concentration, Na2HPO4 and incubation time. The results of this study showed that Leugmi concentration at 25%, Na2HPO4 at 0.1% and incubation time of 24 h were optimal conditions for BioS  production, with a maximum Surface Tension (ST) decreasing capacity of 55% corresponding to 27 mN/m and an Oil Dispersing Activity (ODA) of 30 cm2 corresponding to a diameter of 6 cm. Preliminary characterization of the BioS produced on Luegmi by UV-Spectra and Thin Layer Chromatography showed its lipopeptide nature. Physic-chemical characterization of the produced lipopeptide on Leugmi showed its great surface activities and stabilities at different pH, temperature and salts concentration. The results of this study suggested that Leugmi, an agricultural byproducts can be used as a low-cost substrate to enhance the yield of lipopeptide BioS with great surface activities for potential environmental application.


Assuntos
Bacillus/metabolismo , Sucos de Frutas e Vegetais/análise , Lipopeptídeos/biossíntese , Phoeniceae/química , Tensoativos/metabolismo , Cromatografia em Camada Fina , Concentração de Íons de Hidrogênio , Salinidade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Tensão Superficial , Temperatura
9.
Biodegradation ; 30(4): 259-272, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30390188

RESUMO

Pseudomonas strains isolated from oil contaminated soils were screened for biosurfactant production. Three out of eleven Pseudomonas isolates were selected for their high emulsifying activity (E24 value on n-hexadecane ~ 78%). These isolates (E39, E311 and E313) were identified as members of the P. putida group using phenotypical methods and a molecular approach. To identify the chemical nature of produced biosurfactants, thin layer chromatography and MALDI-ToF mass spectrometry analysis were carried out and revealed lipopeptides belonging to the syringafactin family. The activity of the produced biosurfactants was stable over a pH range of 6-12, at high salinity (10%) and after heating at 80 °C. Tests in contaminated sand micro-bioreactors showed that the three strains were able to degrade diesel. These results suggest the potential of these syringafactin producing strains for application in hydrocarbon bioremediation.


Assuntos
Petróleo , Pseudomonas , Biodegradação Ambiental , Hidrocarbonetos , Solo , Tensoativos
10.
Eng Life Sci ; 18(1): 70-77, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32624863

RESUMO

Surfactants play a very important role in laundry and household cleaning products ingredients. In this research, the application of lipopeptide biosurfactants, produced by Bacillus subtilis SPB1, in the formulation of a washing powder was investigated. The SPB1 biosurfactant was mixed with sodium tripolyphosphate as a builder and sodium sulfate as filler. The efficiency of the formulated detergent composition with different washing conditions to remove a stain from cotton fabric was examined. The results showed that the formulated detergent was effective in oil removal, with optimal washing conditions of pH, temperature, striate and time of washing system of 7, 65°C, 1000 RPM and 60 min, respectively. A comparative study of different detergent compositions (biosurfactant-based detergent, combined biosurfactant-commercial detergent, and a commercial detergent) for the removal of oil and tea stains, proved that the bio-scouring was more effective (>75%) in terms of the stain removal than the commercial powders (<60%). Moreover, the results demonstrated that the biosurfactant acts additively with a commercial detergent and enhances their performance from 33 to 45% in removing oil stain and from 57 to 64% in removing tea stain. As a conclusion, in addition to the low toxicity and the high biodegradability of the microbial biosurfactants, the results of this study have shown that the future use of this lipopeptide biosurfactant as laundry detergent additive is highly promising.

11.
J Microbiol Biotechnol ; 28(1): 95-104, 2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-28750507

RESUMO

Biosurfactants or microbial surfactants are surface-active biomolecules that are produced by a variety of microorganisms. Biodegradability and low toxicity have led to the intensification of scientific studies on a wide range of industrial applications for biosurfactants in the field of environmental bioremediation as well as the petroleum industry and enhanced oil recovery. However, the major issues in biosurfactant production are high production cost and low yield. Improving the bioindustrial production processes relies on many strategies, such as the use of cheap raw materials, the optimization of medium-culture conditions, and selecting hyperproducing strains. The present work aims to obtain a mutant with higher biosurfactant production through applying mutagenesis on Bacillus subtilis SPB1 using a combination of UV irradiation and nitrous acid treatment. Following mutagenesis and screening on blood agar and subsequent formation of halos, the mutated strains were examined for emulsifying activity of their culture broth. A mutant designated B. subtilis M2 was selected as it produced biosurfactant at twice higher concentration than the parent strain. The potential of this biosurfactant for industrial uses was shown by studying its stability to environmental stresses such as pH and temperature and its applicability in the oil recovery process. It was practically stable at high temperature and at a wide range of pH, and it recovered above 90% of motor oil adsorbed to a sand sample.


Assuntos
Bacillus subtilis/metabolismo , Microbiologia Industrial/métodos , Engenharia Metabólica , Mutagênese , Indústria de Petróleo e Gás/métodos , Tensoativos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Bacillus subtilis/efeitos da radiação , Fermentação , Concentração de Íons de Hidrogênio , Ácido Nitroso , Temperatura , Raios Ultravioleta
12.
J Adv Res ; 8(4): 425-433, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28721297

RESUMO

Toothpaste is a gel dentifrice used with a toothbrush as an accessory to clean, keep and promote oral hygiene. The literature review suggests that there are many different formulations of toothpastes and that each of their individual components present specific functions. The concentration of the toothpaste ingredients must be appropriately chosen taking into account the purposes of the toothpaste. Biosurfactants are considered as suitable molecules for application in many formulations such as in toothpaste one. In the present work, two dentifrice formulations were investigated and their efficiencies were tested using chemical surfactant agent and lipopeptide biosurfactant isolated from Bacillus subtilis SPB1. The physicochemical properties were analyzed considering several tests mainly spreading ability, water activity, pH, foaming and cleaning tests. The obtained results indicated that the SPB1 biosurfactant was as efficient as the chemical surfactant confirming its potential utilization in toothpaste formulation compared to the commercial one. The evaluation of the antimicrobial activity of the formulated dentifrice was carried out against eight bacteria. The results demonstrated that the biosurfactant-based product exhibited an important antimicrobial activity, which was very effective against Enterobacter sp and Salmonella typhinirium.

13.
Curr Microbiol ; 74(5): 584-588, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28260117

RESUMO

Vegetative insecticidal proteins produced by some Bacillus thuringiensis strains are specifically toxic to different agricultural pests such as the polyphagous Spodoptera and several other Lepidopteran insects, but one of the major problems found in the use of these biopesticides was the lack of an easy and credible method of quantification of such secreted toxins. Heterologous expression of B. thuringiensis Vip3Aa16 toxin was performed in Escherichia coli then the protein was purified by chromatography. Using blood agar as well as blood agar overlay (zymogram assay), we reported, for the first time, the capacity of Vip3Aa16 to induce hemolysis. The hemolytic activity of this protein was shown to be relatively stable after treatment at 40 °C and at a range of pH between 6.5 and 9. Moreover, a linear relationship was shown between hemolysis levels and Vip3Aa16 concentrations. The model established in the present study could quantify Vip3A toxin as a function of hemolytic activity and the assay proposed showed to be a simple and low-cost method to readily assess Vip3A toxins in liquid cultures and facilitate the use of this kind of bioinsecticides in pest management programs.


Assuntos
Antibiose/genética , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Hemólise , Concentração de Íons de Hidrogênio , Inseticidas , Estabilidade Proteica , Proteínas Recombinantes , Temperatura
14.
J Sci Food Agric ; 96(13): 4310-20, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27098847

RESUMO

Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. They are characterized by high structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface, respectively. Rhamnolipids, trehalolipids, mannosylerythritol lipids and cellobiose lipids are among the most popular glycolipids. They have received much practical attention as biopesticides for controlling plant diseases and protecting stored products. As a result of their antifungal activity towards phytopathogenic fungi and larvicidal and mosquitocidal potencies, glycolipid biosurfactants permit the preservation of plants and plant crops from pest invasion. Also, as a result of their emulsifying and antibacterial activities, glycolipids have great potential as food additives and food preservatives. Furthermore, the valorization of food byproducts via the production of glycolipid biosurfactant has received much attention because it permits the bioconversion of byproducts on valuable compounds and decreases the cost of production. Generally, the use of glycolipids in many fields requires their retention from fermentation media. Accordingly, different strategies have been developed to extract and purify glycolipids. © 2016 Society of Chemical Industry.


Assuntos
Agroquímicos/química , Agentes de Controle Biológico/química , Aditivos Alimentares/química , Glicolipídeos/química , Resíduos Industriais/análise , Tensoativos/química , Agroquímicos/economia , Agroquímicos/isolamento & purificação , Agroquímicos/metabolismo , Animais , Biodegradação Ambiental , Agentes de Controle Biológico/economia , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/metabolismo , Fenômenos Químicos , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/imunologia , Fermentação , Aditivos Alimentares/economia , Aditivos Alimentares/isolamento & purificação , Aditivos Alimentares/metabolismo , Conservantes de Alimentos/química , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Conservantes de Alimentos/metabolismo , Indústria de Processamento de Alimentos/economia , Fungos/química , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Glicolipídeos/economia , Glicolipídeos/isolamento & purificação , Glicolipídeos/metabolismo , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/química , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/metabolismo , Humanos , Resíduos Industriais/economia , Praguicidas/química , Praguicidas/economia , Praguicidas/isolamento & purificação , Praguicidas/metabolismo , Imunidade Vegetal/efeitos dos fármacos , Tensoativos/economia , Tensoativos/isolamento & purificação , Tensoativos/metabolismo
15.
Environ Sci Pollut Res Int ; 23(2): 1742-54, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26396008

RESUMO

Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents.


Assuntos
Aeromonas/metabolismo , Compostos Azo/metabolismo , Corantes/metabolismo , Recuperação e Remediação Ambiental/métodos , Poluentes Químicos da Água/metabolismo , Aeromonas/classificação , Aeromonas/genética , Aeromonas/isolamento & purificação , Biodegradação Ambiental , Polissorbatos/análise , Tensoativos/análise , Têxteis , Águas Residuárias/análise
16.
Environ Sci Pollut Res Int ; 23(7): 6690-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26645234

RESUMO

This study reports the potential of a soil bacterium, Bacillus subtilis strain SPB1, to produce lipopeptide biosurfactants. Firstly, the crude lipopeptide mixture was tested for its inhibitory activity against phytopathogenic fungi. A minimal inhibitory concentration (MIC), an inhibitory concentration at 50% (IC50%), and an inhibitory concentration at 90% (IC90%) values were determined to be 0.04, 0.012, and 0.02 mg/ml, respectively, for Rhizoctonia bataticola with a fungistatic mode of action. For Rhizoctonia solani, a MIC, an IC50%, and IC90% values were determined to be 4, 0.25, and 3.3 mg/ml, respectively, with a fungicidal mode of action. For both of the fungi, a loss of sclerotial integrity, granulation and fragmentation of hyphal mycelia, followed by hyphal shriveling and cell lysis were observed with the treatment with SPB1 biosurfactant fraction. After extraction, separation, and purification, different lipopeptide compounds were identified in the culture filtrate of strain SPB1. Mass spectroscopic analysis confirmed the presence of different lipopeptide compounds consisting of surfactin isoforms with molecular weights of 1007, 1021, and 1035 Da; iturin isoforms with molecular weights of 1028, 1042, and 1056 Da; and fengycin isoforms with molecular weights of 1432 and 1446 Da. Two new clusters of lipopeptide isoforms with molecular weights of 1410 and 1424 Da and 973 and 987 Da, respectively, were also detected. This study reported the ability of a B. subtilis strain to co-produce lipopeptide isoforms with potential use as antifungal compounds.


Assuntos
Bacillus subtilis/metabolismo , Fungicidas Industriais/farmacologia , Lipopeptídeos/farmacologia , Rhizoctonia/efeitos dos fármacos , Microbiologia do Solo , Fungicidas Industriais/isolamento & purificação , Lipopeptídeos/isolamento & purificação , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Rhizoctonia/crescimento & desenvolvimento
17.
Water Sci Technol ; 72(8): 1283-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465297

RESUMO

Citrobacter sedlackii RI11, isolated from acclimated textile effluent after selective enrichment on synthetic dyes, was assessed for malachite green (MG) biotreatment potency. Results indicate that this bacterium has potential for use in effective treatment of MG contaminated wastewaters under shaking conditions at neutral and alkaline pH value, characteristic of typical textile effluents. Also, the newly isolated strain can tolerate higher doses of dye and decolorize up to 1,000 mg/l of dye. When used as microbial surfactant to enhance MG biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized the decolorization efficiency at an optimal concentration of biosurfactant of about 0.075%. Studies ensured that MG removal by this strain could be due to biodegradation and/or adsorption. Results on germination potencies of different seeds using the treated dyes under different conditions favor the use of SPB1 biosurfactant for the treatment of MG.


Assuntos
Citrobacter/metabolismo , Lipopeptídeos/química , Corantes de Rosanilina/metabolismo , Tensoativos/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Bacillus subtilis/química , Biodegradação Ambiental , Citrobacter/isolamento & purificação , Corantes/metabolismo , Germinação/efeitos dos fármacos , Raphanus , Corantes de Rosanilina/toxicidade , Sorghum , Têxteis
18.
Water Sci Technol ; 72(6): 865-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26360745

RESUMO

Bacillus weihenstephanensis RI12, isolated from hydrocarbon contaminated soil, was assessed for Congo Red bio-treatment potency. Results suggested the potential of this bacterium for use in effective treatment of Congo Red contaminated wastewaters under shaking conditions at acidic and neutral pH value. The strain could tolerate higher doses of dyes as it could decolorize up to 1,000 mg/l of Congo Red. When used as microbial surfactant to enhance Congo Red biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized the decolorization efficiency at an optimal concentration of biosurfactant of about 0.075%. Studies ensured that Congo Red removal by this strain could be due to an adsorption phenomena. Germination potencies of tomato seeds using the treated dyes under different conditions showed the efficient biotreatment of the azo dye Congo Red especially with the addition of SPB1 biosurfactant. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing the effective decolorization period; the biosurfactant stimulated bacterial decolorization method may provide a highly efficient, inexpensive and time-saving procedure in the treatment of textile effluents.


Assuntos
Bacillus/metabolismo , Biodegradação Ambiental , Vermelho Congo/metabolismo , Tensoativos/química , Adsorção , Bacillus/classificação , Corantes , Vermelho Congo/química , Concentração de Íons de Hidrogênio , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
19.
Environ Sci Pollut Res Int ; 22(22): 18137-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26178831

RESUMO

Bacillus subtilis SPB1 lipopeptides were evaluated as a natural antifungal agent against Fusarium solani infestation. In vitro antifungal assay showed a minimal inhibitory concentration of about 3 mg/ml with a fungicidal mode of action. In fact, treatment of F. solani by SPB1 lipopeptides generated excessive lyses of the mycelium and caused polynucleation and destruction of the related spores together with a total inhibition of spore production. Furthermore, an inhibition of germination potency accompanied with a high spore blowing was observed. Moreover, in order to be applied in agricultural field, in vivo antifungal activity was proved against the dry rot potato tubers caused by F. solani. Preventive treatment appeared as the most promising as after 20 days of fungi inoculation, rot invasion was reduced by almost 78%, in comparison to that of non-treated one. When treating infected tomato plants, disease symptoms were reduced by almost 100% when applying the curative method. Results of this study are very promising as it enables the use of the crude lipopeptide preparation of B. subtilis SPB1 as a potent natural fungicide that could effectively control the infection of F. solani in tomato and potato tubers at a concentration similar to the commercial fungicide hymexazol and therefore prevent the damage of olive tree.


Assuntos
Antifúngicos/farmacologia , Bacillus subtilis/química , Fusarium/efeitos dos fármacos , Lipopeptídeos/farmacologia , Tensoativos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Bacillus subtilis/metabolismo , Lipopeptídeos/química , Lipopeptídeos/isolamento & purificação , Tubérculos/microbiologia , Tensoativos/química , Tensoativos/isolamento & purificação
20.
World J Microbiol Biotechnol ; 31(7): 1001-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25997688

RESUMO

Biosurfactants are surface-active biomolecules that are produced by a variety of microorganisms. They have gained biotechnologist interest for high diversity and their efficient action in comparison to synthetic emulsifiers. So, we discussed a wide array of screening method based on direct and indirect surface and interfacial tension measurements. Also, this review describes biosurfactant physicochemical properties and natural role in the environment. Also, it presents their tolerance to extreme conditions of temperature, pH and ionic strength, low toxicity and biodegradability. Functional properties like emulsification, foaming, solubilizing and membrane permeabilizing activities were also discussed along with their related application.


Assuntos
Bactérias/metabolismo , Fungos/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Biotecnologia , Concentração de Íons de Hidrogênio , Propriedades de Superfície , Tensoativos/farmacologia , Temperatura
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