Widespread Use Of Surfactants Research Articles

Quorum sensing mediated response mechanism of anammox consortia to anionic surfactant: Molecular simulation and molecular evidence

The widespread use of surfactants raise challenges to biological wastewater treatment. Anaerobic ammonium oxidation (anammox) process has the potential to treat wastewater containing anionic surfactants, but the response of anammox consortia at the molecular level under long-term exposure is unclear. Using high-throughput sequencing and gene quantification, combined with molecular docking, the effect of sodium dodecyl sulfonate (SDS) on anammox consortia were investigated. Levels of reactive oxygen species (ROS) might be lower than the threshold of oxidative damage, while the increase of lactate dehydrogenase (LDH) represented the cell membrane damage. Decreased abundance of functional genes (hdh, hzsA and nirS) indicated the decrease of the anammox bacterial abundance. Trace amounts of N-acyl homoserine lactone (AHL, C6-HSL, C8-HSL and C12-HSL) contained in influent could induce endogenous quorum sensing (QS), which could regulate the correlation between functional bacteria to optimize the microbial community and strengthen the resistance of anammox consortia to SDS. In addition, the proliferation of disinfectant resistance genes might increase the environmental pathogenicity of sewage discharge. This work highlights the potential response mechanism of anammox consortium to surfactants and provides a universal microbial-friendly bioenhancement strategy based on QS.

Surfactants: hygiene’s first line of defence against pollution

Surfactants are a diverse group of compounds that are widely used in a range of industrial, commercial and household applications. They are amphiphilic molecules that contain both hydrophilic and hydrophobic groups, which allow them to interact with both water and oil. Surfactants have a number of important properties, including the ability to reduce surface tension, emulsify liquids and solubilise hydrophobic compounds. These properties make them valuable in a range of applications, including detergents (hygiene products), cosmetics, pharmaceuticals and agricultural products. However, the widespread use of surfactants has also raised concerns about their environmental impacts. This review provides an overview of the properties and applications of surfactants, as well as their environmental impacts, the different types of surfactants and their properties and uses in different applications and the current understanding of the environmental fate and impacts of surfactants, including their interactions with aquatic organisms, microbial communities and natural ecosystems. Finally, ths study discusses strategies for minimising the environmental impacts of surfactants, including the development of biodegradable and environmentally friendly surfactants.

CYTOGENETIC EFFECTS OF SURFACTANTS

Introduction. The widespread use of surfactants in economic activity and life has led to global pollution. The negative impact of surfactants on various characteristics of living organisms has been revealed, which makes a research on the safety of surfactants extremely relevant. Aim. The aim of this work was to study the genotoxic potential of anionic and cationic surfactants. Methods. The influence of anionic (sodium stearate and alkylbenzenesulpho-acid) and cationic (Praepagen TQ) surfactants on the value of the mitotic index, as well as on the regularity of mitosis and meiosis of Triticum aestivum L. cv. Odesa fantasy by standard cytogenetic methods. Main results. Under the action of surfactants in the root meristem of sprouts, the mitotic index significantly decreased and the number of cells containing chromosomal aberrations increased. Among the abnormalities at the ana-telophase stage, cells with lagging chromosomes, fragments, the formation of chromosomal bridges, and complex disorders were observed. These changes were directly proportional to the concentration of the drugs. The action of the cationic drug was less harmful than the action of both anionic drugs. Treatment of plants with surfactants led to a highly reliable increase in the proportion of abnormal MCPs in both the first and second division of meiosis, directly proportional to the concentration of surfactants applied. No differences were found between the first and second meiotic divisions in terms of the frequency of formation of defective MCPs. Both anionic surfactants had a stronger effect than the cationic one; with the use of alkylbenzenesulfonic acid, the degree of violations in microsporocytes was the greatest. Conclusions. A significant decrease in the mitotic index and an increase in the proportion of cells containing chromosomal aberrations in the root meristem of sprouts, as well as a significant increase in the proportion of abnormal MCPs in both the first and second division of meiosis, were found to be directly proportional to the concentration of surfactant. According to all the parameters studied, the action of the cationic drug “Praepagen TQ” was milder than the action of both anionic surfactants.

A dual-chromophore-based cross-reactive fluorescent sensor for efficient discrimination of multiple anionic surfactants

Abstract The widespread use of surfactants and unregulated treatment of environmental media make them well-known environmental pollutants. It is of great significance to develop an effective discriminative sensor that can distinguish various surfactants, especially among anionic surfactants. In the present work, a dual-chromophore-based fluorescent probe was designed and synthesized, where pyrene and rhodamine were used as the signaling units and oligoethoxyl group used as a linker. The introduction of two chromophores was to increase the capacity of multi-wavelength cross-reactivity. Fluorescence measurements revealed that the probe could selectively recognize anionic surfactant SDS over cationic DTAB, neutral Tween 20 and zwitterionic SB3-10 by exhibiting extra rhodamine emission accompanied with pyrene emission. Moreover, the varied fluorescence emission of pyrene monomer, pyrene excimer, and rhodamine empowered the probe with multiple-wavelength cross-reactive responses to different anionic surfactants. The combination of the two ratio signals of pyrene monomer and excimer to rhodamine can generate specific recognition pattern for a particular anionic surfactant and provide a two-dimensional scattering plot for differentiating different anionic surfactants including SDS, SDBS, SDeS, SDSO, SDeSO, and AOT.

Sorption of Organic Electrolytes and Surfactants from Natural Waters by Heterogeneous Membranes

The widespread use of surfactants increasingly requires the development and application of reliable methods for the demineralization of wastewaters, preventing environmental pollution. One of the most reliable and effective methods of demineralization of wastewaters is the electrodialysis method. Studying the behavior of large organic ions in the membrane is important for modeling cell membranes and purification of medicinal and biological preparations. The sorption characteristics of the MA-40 and MK-40 ion-exchange membranes in solutions of simple and organic electrolytes, and in a solution of the surfactant were investigated. It was found that the sorption of organic ions by membranes is mainly of an ion-exchange nature. The moisture content and elasticity of the membranes decreases in solutions of organic electrolytes, during the sorption of which the membrane becomes brittle. A study showed that in the solutions of organic electrolytes, the MA-40 membrane retains high electrochemical activity, while the MK-40 in a solution of the surfactant completely loses it. From the data obtained in this work, it is shown that organic ions do not present a hazard when water is desalted by electrodialysis, whereas sorption of surfactant ions leads to membrane poisoning.

Preparation and Characterization of Stabilizer-Free Phytantriol-Based Water-in-Oil Internally Liquid Crystalline Emulsions

Despite the widespread use of surfactants, there are known issues such as allergic reactions and formulation complications in their use as emulsion stabilizers. In this study, stabilizer-free water-in-oil (W/O) emulsions containing water, phytantriol, and almond oil were prepared by an ultra-turrax homogenizer, a standard laboratory equipment, and a high specialized high-shear device. Parameters such as mixing time, stirring rate, composition, order of addition of phases, and temperature were investigated to systematically optimize the preparation of the formulations through evaluating their accelerated physical stability by a centrifugal sedimentation technique. The liquid crystalline structure of the continuous phase was studied by small-angle X-ray scattering indicating a reverse hexagonal phase (H2). Microscopy images showed the emulsions prepared via high-shear method had smaller water droplets with more uniform shape and better dispersion as confirmed by Fourier-transform infrared–attenuated total reflection spectroscopy. Rheology studies showed a larger yield stress value for emulsions with higher content of phytantriol. Our results indicated that emulsions prepared by the high-shear device with higher amount of phytantriol were the most stable formulations. Applying the correct variables in the preparation of the stabilizer-free emulsions using ultra-turrax homogenizer, one could obtain similarly stable emulsions lacking the uniformity of the droplets.

Binding of Fatty Acid Amide Amphiphiles to Bovine Serum Albumin: Role of Amide Hydrogen Bonding.

The study of protein-surfactant interactions is important because of the widespread use of surfactants in industry, medicine, and pharmaceutical fields. Sodium N-lauroylsarcosinate (SL-Sar) is a widely used surfactant in cosmetics, shampoos. In this paper, we studied the interactions of bovine serum albumin (BSA) with SL-Sar and sodium N-lauroylglycinate (SL-Gly) by use of a number of techniques, including fluorescence and circular dichroism spectroscopy and isothermal titration calorimetry. The binding strength of SL-Sar is stronger than that of structurally similar SL-Gly, which differs only by the absence of a methyl group in the amide nitrogen atom. Also, these two surfactants exhibit different binding patterns with the BSA protein. The role of the amide bond and hence the surfactant headgroup in the binding mechanism is discussed in this paper. It was observed that while SL-Sar destabilized, SL-Gly stabilized the protein structure, even at concentrations less than the critical micelle concentration (cmc) value. The thermodynamics of surfactant binding to BSA was studied by use of ITC. From the ITC results, it is concluded that three molecules of SL-Sar in contrast to only one molecule of SL-Gly bind to BSA in one set of binding sites at room temperature. However, on increasing temperature four molecules of SL-Gly bind to the BSA through H-bonding and van der Waals interactions, due to loosening of the BSA structure. In contrast, with SL-Sar the binding process is enthalpy driven, and very little structural change of BSA was observed at higher temperature.

From 'OOPS to EXIT': A Review of the Origins and Progression of Ex Utero Intrapartum Treatment

Advancement in the safety of obstetric anesthesiology has largely been due to better pharmacotherapy, monitoring devices and airway adjuncts. Similarly, the rate of fetal mortality has declined in the last two decades particularly due to improved neonatal intensive care and the wide-spread use of surfactant for premature births. The field of perinatology has long recognized that certain high-risk fetal anomalies, which previously carried significant mortality rates may now be amenable to the Ex Utero Intrapartum Treatment (EXIT). This review discusses the history of EXIT and focuses on the role of the anesthesiologist during this procedure; with emphasis that the successful outcome of many EXIT procedures is a testament to the advancements in obstetric anesthesiology, our understanding of maternal and fetal physiology, safer anesthetic agents, and improved overall safety of general anesthesia in parturients.

Magnesium Sulfate During Anticipated Preterm Birth for Infant Neuroprotection

Advances in medical care of preterm infants, including the widespread use of surfactant and antenatal steroids, and improvements in ventilation management, have increased the survival rates of some of the most vulnerable infants. Yet, the risk of neurologic impairment and long‐term medical complications remains a concern. Recently, the use of magnesium sulfate during anticipated preterm birth has been identified as a potential treatment to reduce adverse neurologic outcomes among preterm infants. This article discusses the use of magnesium sulfate for anticipated preterm birth to reduce neurologic impairment in preterm infants, including current clinical practice guidelines and implications for nurses.

Surfactant replacement therapy--economic impact.

Surfactant replacement is an effective treatment for neonatal respiratory distress syndrome. (RDS). As widespread use of surfactant is becoming a reality, it is important to assess the economic implications of this new form of therapy. A comparison study was carried out at the Neonatal Intensive Care Unit (NICU) of Northwest Armed Forces Hospital, Saudi Arabia. Among 75 infants who received surfactant for RDS and similar number who were managed during time period just before the surfactant was available, but by set criteria would have made them eligible for surfactant. All other management modalities except surfactant were the same for all these babies. Based on the intensity of monitoring and nursing care required by the baby, the level of care was divided as: Level IIIA, IIIB, Level II, Level I. The cost per day per bed for each level was calculated, taking into account the use of hospital immovable equipment, personal salaries of nursing, medical, ancillary staff, overheads and maintenance, depreciation and replacement costs. Medications used, procedures done, TPN, oxygen, were all added to individual patient's total expenditure. 75 infants in the Surfactant group had 62 survivors. They spent a total of 4300 days in hospital. (av 69.35) Out of which 970 d (av 15.65 per patient) were ventilated days. There were 56 survivors in the non-surfactant group of 75. They had spent a total of 5023 days in the hospital (av 89.69/patient) out of which 1490 were ventilated days (av 26.60 d). Including the cost of surfactant (two doses), cost of hospital stay for each infant taking the average figures of stay would be SR 118, 009.75 per surfactant treated baby and SR 164, 070.70 per non-surfactant treated baby. The difference of 46,061 SR is 39.03% more in non-surfactant group. One Saudi rial = 8 Rs (approx at the time study was carried out.) Medical care cost varies from place to place. However, it is definitely cost-effective where surfactant is concerned. Quality adjusted life years (QALY) for NICU care compares favourably with cost per QALY of several forms of adult health interventions. Audit, both medical and financial, of these services, at regular intervals is essential.

Risk Factors for Chronic Lung Disease in the Surfactant Era: A North Carolina Population-based Study of Very Low Birth Weight Infants

To identify risk factors for chronic lung disease (CLD) in a population-based cohort of very low birth weight infants, born in an era of surfactant usage. We specifically investigated the effects of antenatal steroids, nosocomial infection, patent ductus arteriosus (PDA), fluid management, and ventilator support strategies. Data were prospectively collected on 1244 infants born in North Carolina in 1994 with birth weights 500 to 1500 g, and treated at 1 of the 13 intensive care nurseries across the state. The outcome of interest was CLD, defined as dependency on supplemental oxygen at 36 weeks' postmenstrual age. Multivariate odds ratios (OR) and 95% confidence intervals (CI) were estimated with logistic regression models. Among 865 survivors to 36 weeks' postmenstrual age, 224 (26%) had CLD. Nosocomial infection (OR: 2.0; 95% CI: 1.4-3.3), fluid intake on day 2 (OR: 1.06 per 10 mL increase; 95% CI: 1.01-1.11), and the need for ventilation at 48 hours of life (OR: 2.2; 95% CI: 1.3-3.7) were associated with an increased risk of CLD. Among infants ventilated at 48 hours, nosocomial infection (OR: 1.64; 95% CI: 1.02-2.62) and PDA (OR: 1.9; 95% CI: 1.2-3.1) were associated with an increased risk. No association was found with antenatal steroid receipt or increased levels of ventilator support. This analysis suggests that with widespread use of surfactant, nosocomial infection, PDA, and water balance persist as risk factors for CLD.

Developmental Care Does Not Alter Sleep and Development of Premature Infants

The Neonatal Individualized Developmental Care Program (NIDCAP) for very low birth weight (VLBW) preterm infants has been suggested by Als et al to improve several medical outcome variables such as time on ventilator, time to nipple feed, the duration of hospital stay, better behavioral performance on Assessment of Preterm Infants' Behavior (APIB), and improved neurodevelopmental outcomes. We have tested the hypothesis of whether the infants who had received NIDCAP would show advanced sleep-wake pattern, behavioral, and neurodevelopmental outcome. Thirty-five VLBW infants were randomly assigned to receive NIDCAP or routine infant care. The goals for NIDCAP intervention were to enhance comfort and stability and to reduce stress and agitation for the preterm infants by: a) altering the environment by decreasing excess light and noise in the neonatal intensive care unit (NICU) and by using covers over the incubators and cribs; b) use of positioning aids such as boundary supports, nests, and buntings to promote a balance of flexion and extension postures; c) modification of direct hands-on caregiving to maximize preparation of infants for, tolerance of, and facilitation of recovery from interventions; d) promotion of self-regulatory behaviors such as holding on, grasping, and sucking; e) attention to the readiness for and the ability to take oral feedings; and f) involving parents in the care of their infants as much as possible. The infants' sleep was recorded at 36 weeks postconceptional age (PCA) and at 3 months corrected age (CA) using the Motility Monitoring System (MMS), an automated, nonintrusive procedure for determining sleep state from movement and respiration patterns. Behavioral and developmental outcome was assessed by the Neurobehavioral Assessment of the Preterm Infant (NAPI) at 36 weeks PCA, the APIB at 42 weeks PCA, and by the Bayley Scales of Infant Development (BSID) at 4, 12, and 24 months CA. Sleep developmental measures at 3 months CA showed a clear developmental change compared with 36 weeks PCA. These include: increased amount of quiet sleep, reduced active sleep and indeterminate sleep, decreased arousal, and transitions during sleep. Longest sleep period at night showed a clear developmental effect (increased) when comparing nighttime sleep pattern of infants at 3 months with those at 36 weeks of age. Day-night rhythm of sleep-wake increased significantly from 36 weeks PCA to 3 months CA. However, neither of these sleep developmental changes showed any significant effects of NIDCAP intervention. Although all APIB measures showed better organized behavior in NIDCAP patients, neither NAPI nor Bayley showed any developmental advantages for the intervention group. The neurodevelopmental outcome measured by the Bayley at 4, 12, and 24 months CA showed 64% of the NIDCAP intervention group at the lowest possible score compared with 33% of the control group. These findings could not be explained by the occurrence of intraventricular hemorrhage or the socioeconomic status of the parents, which showed no significant group effect. The results of this study, including measures of sleep maturation and neurodevelopmental outcome up to 2 years of age did not demonstrate that the NIDCAP intervention results in increased maturity or development. Buehler et al (Pediatrics. 1995;96:923-932) have reported that premature infants (N = 12; mean gestational age 32 weeks, mean birth weight 1700 g) who received developmental care compared with a similar group of infants who received routine care showed better organized behavioral performance on an APIB assessment at 42 weeks PCA. None of the medical outcome measures were significantly different in this study. Although our APIB results are in agreement, the results of the NAPI, the Bayley and sleep measures do not show an increase in neurodevelopmental maturation. In the earlier report by Als et al (Journal of the American Medical Associatio

Prospective longitudinal study of 1154 babies with RDS treated with natural porcine surfactant (NPS). † 1265

Objective- Despite the widespread use of surfactant, long term data on outcome to discharge are scarce. We therefore designed a prospective study to evaluate health and developmental outcomes in neonates with RDS routinely treated with NPS and followed-up until the age of 4 years.

Toxicology of Surfactants Used in Cosmetics

The widespread use of surfactants in everyday products requires that the desired properties as well as the unwanted effects are known in order to recognize possible risks and prevent any damage to the health of humans. To understand the effects of surfactants on the organism, their most important biochemical effects, which depend on the interaction of surface active agents with basic biological structures like membranes, proteins, and enzymes are discussed. Following this discussion the local effects of surfactants are described: effects encountered directly at the point of contact with the outer surfaces of the body, such as skin and ‘mucous membrane irritation as well as allergies arising from skin contact. After this section the toxicokinetic properties of surfactants are discussed, providing information about type and extent of absorption of surfactants by organisms, metabolic pathways, and surfactant elimination. In contrast to local effects, the section on systemic effects deals with reactions arising after the substance has entered the organism by ingestion, skin penetration, or inhalation.

PENETRATION OF OCTYLPHENOXY SURFACTANTS THROUGH ISOLATED TOMATO FRUIT CUTICLES

Despite the widespread use of surfactants to enhance the performance of foliar applied chemicals, the mechanisms for this enhancement are poorly understood. The penetration of surfactant per se through the cuticular membrane (CM) may play a pivotal role. Thus, we examined CM penetration by octylphenoxy surfactants (Triton X series) using a finite dose (Franz) diffusion cell. The effect of hydrophile length was studied using 14C surfactant (15.9 mm in 20 mm citrate buffer: pH 3.2) with 3, 9.5, 12, 16, and 40 ethylene oxide units per molecule (EO). One 5-μl droplet of surfactant solution was applied to the outer morphological surface of CM enzymatically isolated from mature tomato fruit. The inner CM surface remained in contact with stirred buffer at 25°C. The buffer was sampled periodically through a side portal over 648 h. Penetration curves (time vs. % penetrated) for all surfactants were characterized by three phases: lag, linear, and asymptotic. Lag: There was no effect of EO on the length of the lag phase (average 5 h) Linear: Steady state penetration (0.6 to 1.1% / h) was inversely related to log EO content. Asymptotic: About 70% of applied short EO (3 to 16) surfactants penetrated while 25% of the 40 EO penetrated in 648 h.

PENETRATION OF OCTYLPHENOXY SURFACTANTS THROUGH ISOLATED TOMATO FRUIT CUTICLES

Despite the widespread use of surfactants to enhance the performance of foliar applied chemicals, the mechanisms for this enhancement are poorly understood. The penetration of surfactant per se through the cuticular membrane (CM) may play a pivotal role. Thus, we examined CM penetration by octylphenoxy surfactants (Triton X series) using a finite dose (Franz) diffusion cell. The effect of hydrophile length was studied using 14C surfactant (15.9 mm in 20 mm citrate buffer: pH 3.2) with 3, 9.5, 12, 16, and 40 ethylene oxide units per molecule (EO). One 5-μl droplet of surfactant solution was applied to the outer morphological surface of CM enzymatically isolated from mature tomato fruit. The inner CM surface remained in contact with stirred buffer at 25°C. The buffer was sampled periodically through a side portal over 648 h. Penetration curves (time vs. % penetrated) for all surfactants were characterized by three phases: lag, linear, and asymptotic. Lag: There was no effect of EO on the length of the lag phase (average 5 h) Linear: Steady state penetration (0.6 to 1.1% / h) was inversely related to log EO content. Asymptotic: About 70% of applied short EO (3 to 16) surfactants penetrated while 25% of the 40 EO penetrated in 648 h.

Interaction of polyoxyethylene alkyl ethers with cholesterol monolayers

Despite the widespread use of surfactants no clear understanding of the mechanisms of their interactions with biological membranes exists. Surface pressure/area ( π A ) curves were obtained for cholesterol before and after addition of polyoxyethylene alkyl ethers. In the presence of the surfactants the π A curve altered depending on the type and concentration of the amphiphile. In all cases, however, a concentration dependent biphasic effect was observed. Initial increases in π, at low surfactant concentration, suggest penetration of the monolayer. At higher surfactant concentration π decreased suggesting monolayer disruption. Surfactants based on a C 12 alkyl chain were more effective in penetrating and disrupting the monolayer than those based on a C 18 chain.