Characterization of Lipopeptides Biosurfactants Produced by a Newly Isolated Strain Bacillus Subtilis ZNI5: Potential Environmental Application

2021 ◽  
Author(s):  
Mnif Inès ◽  
Hayfa Rajhi ◽  
Amir Bouallegue ◽  
Nour Trabelsi ◽  
Dhouha Ghribi
Keyword(s):  
Surface Tension ◽  
Bacillus Subtilis ◽  
High Performance ◽  
Surface Active Agent ◽  
Active Agent ◽  
Industrial Applications ◽  
Exchange Chromatography ◽  
Environmental Application ◽  
Molecular Weights ◽  
Lipopeptide Biosurfactant

Abstract Strain ZNI5, isolated from a hydrocarbon contaminated soil and identified as Bacillus subtilis after 16s rDNA sequence, grew and produced lipopeptides biosurfactants when cultured on glucose based media. After purification by anionic exchange chromatography and identification Reverse Phase High Performance Liquid Chromatography-Mass Spectrometry, the biosurfactant produced by ZNI5 were determined to be cyclic lipopeptides homologues. Four families of lipopeptides were identified by HPLC-MS analysis. They belongs to surfactin isoforms with molecular weights of 979, 993, 1007, 1021 and 1035 Da; iturin isoforms with molecular weights of 1028, 1042 and 1056 Da; Licheniformin with molecular weight of 1410 and newly identified isoforms named Inesfactin with molecular weights of 973 and 987 Da. Functional properties of the ZNI5 biosurfactant were studied. It was characterized as a powerful surface-active agent that decreases the surface tension of water from 72 mN/m to about 32 mN/m with a CMC value of 350 mg/L more efficient than chemical surfactants (Triton X100; CTAB and SDS). It has the capacity to disperse oil to about 80 mm at a concentration of 800 mg/L showing close efficiencies to the listed chemical surfactants. In addition, by studying the surface tension decrease capacity and the oil displacement activity, ZNI5 lipopeptide biosurfactant showed great thermal, pH and salts activity and stability enabling its use in the bioremediation fields and for diverse industrial applications.

Antifreeze glycoproteins in the plasma of Newfoundland Atlantic cod (Gadus morhua)

1981 ◽  
Vol 59 (11) ◽  
pp. 2186-2192 ◽  
Author(s):  
Choy L. Hew ◽  
Don Slaughter ◽  
Garth L. Fletcher ◽  
Shashikant B. Joshi
Keyword(s):  
Amino Acid ◽  
High Performance ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Antifreeze Proteins ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Polar Cod ◽  
Antifreeze Glycoproteins ◽  
Molecular Weights

The plasma of the Atlantic cod, Gadus morhua, contained antifreeze glycoproteins which were present only during the winter months. The antifreeze proteins were isolated, using gel filtration and ion exchange chromatography, and characterized by high performance liquid chromatography. The antifreeze proteins appeared to consist of at least seven components with molecular weights ranging from 2 500 to 33 000. Chemical analysis of the larger components showed a predominance of alanine, threonine, and galactosamine in a ratio of 2:1:1. The smaller peptides contained proline, in addition to alanine and threonine. The amino acid sequence of the smallest glycopeptide (molecular weight 2500) was found to be Ala Ala Thr Pro Ala Thr Ala Ala Thr Pro Ala Thr Ala Ala.These glycoproteins are very similar, if not identical, in amino acid and carbohydrate composition to those isolated from Antaractic nototheniids and several northern gadoids. The sequence of the smallest glycopeptide from the Atlantic cod is identical to that reported for the polar cod, Boreogadus saida.

scholarly journals Effect of an Alcohol-Based Caries Detector on the Surface Tension of Sodium Hypochlorite Preparations

2015 ◽  
Vol 26 (1) ◽  
pp. 66-68 ◽  
Author(s):  
Giampiero Rossi-Fedele ◽  
Andrea R. Guastalli
Keyword(s):  
Surface Tension ◽  
Sodium Hypochlorite ◽  
Surface Active Agent ◽  
Active Agent ◽  
Pendant Drop ◽  
Root Canal Irrigants ◽  
Significant Difference ◽  
Surface Active ◽  
Pendant Drop Method

The purpose of this study was to evaluate the effect of an alcohol-based caries detector (Kurakay) on the surface tension of a conventional sodium hypochlorite (NaOCl) preparation, and a product containing a surface-active agent (Chlor-XTRA). The surface tensions of the following solutions were tested: NaOCl, a mixture of NaOCl and Kurakay 9:1 w/w, Chlor-XTRA, a mixture of Chlor-XTRA and Kurakay 9:1 w/w. Ten measurements per test solution were made at 20 C, using an optical method called the "Pendant drop method", with a commercially available apparatus. The addition of Kurakay reduced the surface tension for NaOCl (p<0.05) whilst no significant difference was detected for Chlor-XTRA (p>0.05). Statistically significant differences between the NaOCl and Chlor-XTRA groups were found (p<0.05). The addition of an alcohol-based caries detector resulted in a reduction of the original surface tension values for NaOCl only. Taking into account the fact that mixtures of NaOCl and Kurakay have been used to assess the penetration of root canal irrigants in vitro, the related changes in surface tension are a possible source of bias.

A reciprocal theorem for Marangoni propulsion

2014 ◽  
Vol 741 ◽  
Author(s):  
Hassan Masoud ◽  
Howard A. Stone
Keyword(s):  
Surface Tension ◽  
Surface Active Agent ◽  
Active Agent ◽  
Reynolds Numbers ◽  
The Self ◽  
Reciprocal Theorem ◽  
Surface Tension Gradient ◽  
Spheroidal Particle ◽  
Surface Active ◽  
Translational Speed

AbstractWe study the Marangoni propulsion of a spheroidal particle located at a liquid–gas interface. The particle asymmetrically releases an insoluble surface-active agent and so creates and maintains a surface tension gradient leading to the self-propulsion. Assuming that the surface tension has a linear dependence on the concentration of the released agent, we derive closed-form expressions for the translational speed of the particle in the limit of small capillary, Péclet and Reynolds numbers. Our derivations are based on the Lorentz reciprocal theorem, which eliminates the need to develop the detailed flow field.

scholarly journals High Performance Conditioning Shampoo with Hyaluronic Acid and Sustainable Surfactants

Cosmetics ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 71
Author(s):  
Kelly Yorke ◽  
Samiul Amin
Keyword(s):  
Molecular Weight ◽  
Surface Tension ◽  
Hyaluronic Acid ◽  
High Performance ◽  
Low Cost ◽  
Hair Follicles ◽  
Shear Rates ◽  
Molecular Weights ◽  
Surface Activity Properties ◽  
Alkyl Polyglucoside

Recently, consumers have become invested in more natural and sustainable ingredients contained in personal care products. Unfortunately, cationic surfactants are still heavily relied on as primary conditioning agents in products such as conditioning shampoos because of their ability to cling well to the negatively charged surface of hair follicles. Additionally, sulfates are utilized as cleansing agents because they are highly effective and low cost. The objective of this study is to find a more sustainable formulation for a conditioning shampoo without compromising the desired wet combing, rheological, and surface activity properties. The systems which were investigated contained hyaluronic acid (HA) at a variety of molecular weights and concentrations, in combination with a surfactant, either acidic sophorolipid (ASL) or alkyl polyglucoside (APG), and varying the presence of sodium chloride. A Dia-stron was utilized to test the wet combing force, a rheometer recorded the viscosity at various shear rates, and a tensiometer measured the surface tension of the samples before a visual foaming study was conducted. Molecular weight and concentration seemed to have a large impact on wet combing force, as well as rheology, with the largest molecular weight and concentration producing the lowest friction coefficient and desired rheological profile. The addition of a surfactant significantly aids in the reduction in surface tension and increased foamability. Therefore, the optimal system to achieve the largest reduction in wet combing force, large viscosity with shear-thinning behavior, and relatively low surface tension with decent foaming is composed of 1% HA at 800 kDa, 10% ASL and 1% NaCl. This system shows a viable sulfate-free and silicone-free option that can achieve both conditioning and cleansing.

scholarly journals Perlukah Kita Menggunakan Obat Kumur?

2017 ◽  
Vol 2 (4) ◽  
pp. 14
Author(s):  
Nia Yuniarsih
Keyword(s):  
Surface Tension ◽  
Surface Active Agent ◽  
Active Agent ◽  
Wetting Agent ◽  
Surface Active

Obat kumur dapat digunakan untuk dua tujuan. Mereka bersifat terapeutik dan kosmetik. Bersifat terapeutik pada pembedahan mulut atau mencuci, untuk mengurangi plak, radang gusi, karies gigi, dan stomatitis.Surfaktan digunakan karena dapat membantu pelarut rasa dan menghilangkan kotoran dengan memberikan tindakan berbusa. Agen pembasah (wetting agent) didefinisikan sebagai senyawa yang mempunyai aktifitas permukaan (surface active agent) sehingga dapat menurunkan tegangan permukaan (surface tension) antara udara – cairan dan cairan – cairan yang terdapat dalam suatu sistem.Jadi obat kumur merupakan pembersih tambahan dan bukan pengganti. Pada akhirnya, obat kumur hanya berfungsi untuk "penyegar" mulut.Keyword : obat kumur, radang, aktivitas permukaan, mulut

Towards an Improved Megasonic Cleaning Process: Influence of Surface Tension on Bubble Activity in Acoustic Fields

2012 ◽  
Vol 195 ◽  
pp. 173-176
Author(s):  
Elisabeth Camerotto ◽  
Steven Brems ◽  
Marc Hauptmann ◽  
Jelle Lurquin ◽  
Herbert Struyf ◽  
...  
Keyword(s):  
Surface Tension ◽  
Semiconductor Industry ◽  
Surface Active Agent ◽  
Active Agent ◽  
Bubble Collapse ◽  
Physical Parameters ◽  
Particle Removal ◽  
Acoustic Fields ◽  
Produce Water ◽  
Megasonic Cleaning

Removal of particulate residues represents a very challenging step in current CMOS-technology nodes. The continued miniaturization and the introduction of novel materials in the semiconductor industry have resulted in very stringent requirements for device fabrication steps such as cleaning processes [. Physical forces, acting directly on the surface to be cleaned, are currently employed for delicate particle removal as an alternative to more aggressive chemistries [2]. High frequency ultrasounds (500 kHz 4 MHz), or megasonics, rely on the action of oscillating bubbles created during the ultrasonic agitation of the cleaning liquid. Strongly oscillating gas bubbles are able to generate shear forces, which are considered to be responsible for cleaning [3]. However, collapsing bubbles close to a surface can also produce water jets and shockwaves which lead to damage of fragile structures. Fundamental research is needed in order to overcome these issues by improving the understanding of the physical parameters playing a role in the acoustic cavitation of bubbles. This study reports the effects of lowering the surface tension of the liquid bulk on the bubble activity in the MHz range. A lower surface tension (45 mN/m) with respect to water (72 mN/m) is obtained by adding a non-ionic surface-active agent (TritonX-100). After fully characterizing its wettability, a cleaning solution containing surfactant is investigated under pulsed and continuous acoustic fields, for different acoustic amplitudes and gas concentrations. The aim is to increase bubble activity while reducing the strength of the bubble collapse. The results obtained can be useful in tuning megasonic cleaning systems towards more efficient processes.

scholarly journals Impact of the Purification Process on the Spray-Drying Performances of the Three Families of Lipopeptide Biosurfactant Produced by Bacillus subtilis

2021 ◽  
Vol 9 ◽  
Author(s):  
Antoine Vassaux ◽  
Marie Rannou ◽  
Soline Peers ◽  
Théo Daboudet ◽  
Philippe Jacques ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Spray Drying ◽  
Freeze Drying ◽  
Industrial Applications ◽  
Purification Process ◽  
Purification Step ◽  
Wide Range ◽  
Lipopeptide Biosurfactant ◽  
The Impact ◽  
Spray Dried

Lipopeptides produced by Bacillus subtilis display many activities (surfactant, antimicrobial, and antitumoral), which make them interesting compounds with a wide range of applications. During the past years, several processes have been developed to enable their production and purification with suitable yield and purity. The already implemented processes mainly end with a critical drying step, which is currently achieved by freeze-drying. In this study, the possibility to replace this freeze-drying step with a spray-drying one, more suited to industrial applications, was analyzed. After evaluating their thermal resistance, we have developed a spray-drying methodology applicable for the three lipopeptides families produced by B. subtilis, i.e., surfactin, mycosubtilin (iturin family), and plipastatin (fengycin family). For each lipopeptide, the spray-drying procedure was applied at three steps of the purification process by ultrafiltration (supernatant, diafiltered solution, and pre-purified fraction). The analysis of the activities of each spray-dried lipopeptide showed that this drying method is not decreasing its antimicrobial and biosurfactant properties. The methodology developed in this study enabled for the first time the spray-drying of surfactin, without adjuvants’ addition and regardless of the purification step considered. In the case of fengycin and mycosubtilin, only diafiltered solution and purified fraction could be successfully spray-dried without the addition of adjuvant. Maltodextrin addition was also investigated as the solution for the direct drying of supernatant. As expected, the performances of the spray-drying step and the purity of the powder obtained are highly related to the purification step at which the product was dried. Interestingly, the impact of mycosubtilin concentration on spray-drying yield was also evidenced.

Surface Properties of Molten Bismuth-Bismuth Chloride in Contact with Uranium Dioxide

1961 ◽  
Vol 14 (3) ◽  
pp. 409 ◽  
Author(s):  
DH Bradhurst ◽  
AS Buchanan
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Surface Properties ◽  
Uranium Dioxide ◽  
Surface Active Agent ◽  
Active Agent ◽  
Effective Surface ◽  
Liquid Bismuth ◽  
Surface Active ◽  
Bismuth Chloride

The wetting of uranium dioxide by liquid bismuth has been investigated by means of measurements of surface tension of the liquid and contact angle of the liquid on the solid. Bismuth chloride in low concentration was found to be a very effective surface active agent in improving the wetting of the solid by the metal.

Emulsifying composition for increase of oil recovery efficiency of high viscous oils

2021 ◽  
pp. 22-28
Author(s):  
R.G. Ismailov ◽  
◽  
E.F. Veliev ◽  
◽  
◽  
...  
Keyword(s):  
Surface Tension ◽  
Oil Recovery ◽  
Emulsion Stability ◽  
Surface Active Agent ◽  
Active Agent ◽  
Heavy Oils ◽  
Viscous Oil ◽  
Surface Active ◽  
Oil Water ◽  
The Stability

Nowadays, one of the more perspective technologies for oil recovery increase in the fields with heavy oils is formation of intrastratal emulsion. The paper presents the research on the increase of oil recovery in the fields with heavy oil via injection of combined composition based on the viscosity minimizer and surface active agent. Obtained composition allows significantly increase the stability of intrastratal emulsion, dramatically reducing the values of surface tension in the border of oil/water. The analysis of synergetic efficiency for suggested composition on the emulsion stability, surface tension and rheological properties has been carried out. More efficient concentrations of composition components have been specified. Obtained results have been justified with experiments on the replacement of high viscous oil from Galmaz field on the sand packed tubes of reservoir.

Application Performances of Gemini Surfactant as Silk Degumming Auxiliaries

2011 ◽  
Vol 233-235 ◽  
pp. 147-150
Author(s):  
Xiang Rong Wang ◽  
Peng Kun Fan ◽  
Yun Zhang
Keyword(s):  
Surface Tension ◽  
Surfactant Concentration ◽  
Gemini Surfactant ◽  
Surface Active Agent ◽  
Active Agent ◽  
Silk Fabric ◽  
Surface Activities ◽  
Anionic Gemini Surfactant ◽  
Surface Active ◽  
Better Than

To investigate the Application Performances of the anionic gemini surfactant Ethanediyl-α,ω-bis(sodium N-lauroyl-β-alaninate)(EBLA) as silk degumming auxiliaries, the surface activity of the gemini surfactant was measured by the surface tension method. The dependence of degumming rate on surfactant concentration and degumming time were discussed, and the whiteness, tensile strength and capillary effect of the degummed silk fabric were measured. The results revealed that the gemini surfactant possessed excellent surface activities and its degumming effect was pretty good, the critical micelle concentration(CMC) of EBLA was 4.74×10-5 mol·dm-3, and the surface tension at the CMC(γCMC) of it was 26.6 mN·m-1. With lower dosage of the surface active agent and shorter degumming time, the perform indexes of the fabric degummed by the gemini surfactant EBLA were better than those of the fabric degummed by marseille soap.

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