Preparation of Microemulsion from an Alkyl Polyglycoside Surfactant and Tea Tree Oil

Advance of Microemulsion and Application for Enhanced Oil Recovery

With the ongoing advancement in oil exploration, microemulsion, as an innovative oil displacement method, has garnered considerable attention owing to its exceptional physicochemical properties in enhancing crude oil recovery. As such, this study initially delineates the fundamental concepts, classifications, formation mechanisms, advantages, and preparation methodologies of microemulsions. Subsequently, it introduces the selection criteria for microemulsion components, followed by an elucidation of the characterization methods for microemulsions based on these criteria. Furthermore, it examines the factors influencing the efficacy of microemulsions in enhancing oil recovery through two distinct methods, along with the effects of various formulation microemulsions under laboratory and oilfield conditions. Additionally, it outlines prospects, challenges, and future development trends pertaining to microemulsions.

Micro-nanoemulsion and nanoparticle-assisted drug delivery against drug-resistant tuberculosis: recent developments

Tuberculosis (TB) is a major global health problem and the second most prevalent infectious killer after COVID-19. It is caused by Mycobacterium tuberculosis (Mtb) and has become increasingly challenging to treat due to drug resistance. The World Health Organization declared TB a global health emergency in 1993. Drug resistance in TB is driven by mutations in the bacterial genome that can be influenced by prolonged drug exposure and poor patient adherence. The development of drug-resistant forms of TB, such as multidrug resistant, extensively drug resistant, and totally drug resistant, poses significant therapeutic challenges. Researchers are exploring new drugs and novel drug delivery systems, such as nanotechnology-based therapies, to combat drug resistance. Nanodrug delivery offers targeted and precise drug delivery, improves treatment efficacy, and reduces adverse effects. Along with nanoscale drug delivery, a new generation of antibiotics with potent therapeutic efficacy, drug repurposing, and new treatment regimens (combinations) that can tackle the problem of drug resistance in a shorter duration could be promising therapies in clinical settings. However, the clinical translation of nanomedicines faces challenges such as safety, large-scale production, regulatory frameworks, and intellectual property issues. In this review, we present the current status, most recent findings, challenges, and limiting barriers to the use of emulsions and nanoparticles against drug-resistant TB.

Effects of adding tea tree oil on growth performance, immune function, and intestinal function of broilers

The aim of this study was to investigate the effects of adding tea tree oil (TTO) in the basal diet on growth performance, immune function, and intestinal function in broilers. This study utilized 1,650 one-day-old broilers with good health and similar body weight. Subjects were randomized into 5 groups with 6 replicates each: the control group (CON, basal diet), positive control group (PCG, basal diet + 100 mg/kg oregano oil in diet), low-dose TTO group (TTO-L, 50 mg/kg TTO added in the basal diet), medium-dose TTO group (TTO-M, 100 mg/kg TTO added in the basal diet), and high-dose TTO group (TTO-H, 200 mg/kg TTO added in the basal diet). The whole test period lasted 28 d. The results showed that the broilers fed with TTO supplemented diet had significantly higher body weight and average daily gain (ADG) (P = 0.013), and had a lower feed conversion ratio (F/G) (P = 0.010) throughout the trial period. The index of thymus in TTO-M increased significantly compared to CON (P = 0.015) on d 28. On d 14 and 28, C3, IFN-γ, TNF-α, and IL-2 levels in TTO-L serum were significantly increased (P < 0.001); the 3 test groups supplemented with TTO had significantly higher titers of avian influenza H9 subtype in their serum (P < 0.05). Tea tree oil supplement in the diet also had a positive and significant effect on the intestinal morphology of broilers throughout the experiment (P < 0.05). These results indicate that TTO has the ability to promote broiler growth, regulate immunity, and improve intestinal morphology. The proposed dosage of adding 50 mg/kg in broiler basal diets provides a theoretical basis for its subsequent use in livestock feeds.

Synthesis of Carboxyl Modified Polyether Polysiloxane Surfactant for the Biodegradable Foam Fire Extinguishing Agents

It is necessary to develop novel and efficient alternatives to fluorocarbon surfactant and prepare fluorine-free environmentally-friendly fire extinguishing agent. The carboxyl modified polyether polysiloxane surfactant (CMPS) with high surface activity was synthesized via the esterification reaction using hydroxyl-containing polyether modified polysiloxane (HPMS) and maleic anhydride (MA) as raw materials. The process conditions of the esterification reaction were optimized by orthogonal tests, and the optimum process parameters were determined as follows: reaction temperature of 85 °C, reaction time of 4.5 h, isopropyl alcohol content of 20% and the molar ratio of HPMS/MA of 1/1. The chemical structure, surface activity, aggregation behavior, foam properties, wetting properties and electron distribution were systematically investigated. It was found that the carboxyl group was successfully grafted into silicone molecule, and the conjugated system was formed, which changed the interaction force between the molecules and would affect the surface activity of the aqueous solution. The CMPS exhibited excellent surface activity and could effectively reduce the water's surface tension to 18.46 mN/m. The CMPS formed spherical aggregates in aqueous solution, and the contact angle value of CMPS is 15.56°, illustrating that CMPS had excellent hydrophilicity and wetting performance. The CMPS can enhance the foam property and has good stability. The electron distribution results indicate that the introduced carboxyl groups are more inclined towards the negative charge band, which would be conducive to weak the interaction between molecules and improve the surface activity of the solution. Consequently, new foam fire extinguishing agents were prepared by using CMPS as a key component and they exhibited excellent fire-fighting performance. The prepared CMPS would be the optimal alternative to fluorocarbon surfactant and could be applied in foam extinguishing agents.

Efficient Development of Green Emulsifier/Emollient-Based Emulsion Vehicles: From RSM Optimal Experimental Design to Abridged In Vivo Assessment

Since natural-origin, sustainable ingredients are preferred by modern consumers, novel emulsifiers and emollients keep entering the market. This study hypothesizes that a combination of in silico, instrumental tools and simplified sensory studies could be used to efficiently characterize emulsions in a shorter timeframe. A total of 22 rather simple o/w emulsions were prepared by a time/energy-saving emulsification process. A natural mixed emulsifier (Lauryl Glucoside/Myristyl Glucoside/Polyglyceryl-6 Laurate) and two emollients (both with INCI name C15-19 Alkane) were used. The performed D-optimal experimental design within the response surface method (RSM) significantly narrowed down the number of samples about to enter the stage of texture, friction and sensory studies to the samples comprising 30% of a respective Emogreen emollient and 2% or 3% of the emulsifier. The sample comprising 2% emulsifier/30% Emogreen^® L15 showed significantly higher firmness (42.12 mN) when compared to the one with 2% emulsifier/30% Emogreen^® L19 (33.62 mN), which was somewhat unexpected considering the emollients' inherent viscosity values (4.5 mPa·s for L15 and 9 mPa·s for L19). The sample with 2% emulsifier/30% Emogreen^® L19 managed to maintain the lowest friction, while the one with 3% emulsifier/30% Emogreen^® L19 released its full lubricating potential in the second part of the measurement (30-60 s). The obtained results revealed the strengths and weaknesses of each formulation, narrowing down their possible applications in the early development stage.

Amelioration of Biogas Production from Waste-Activated Sludge through Surfactant-Coupled Mechanical Disintegration

The current study intended to improve the disintegration potential of paper mill sludge through alkyl polyglycoside-coupled disperser disintegration. The sludge biomass was fed to the disperser disintegration and a maximum solubilization of 6% was attained at the specific energy input of 4729.24 kJ/kg TS. Solubilization was further enhanced by coupling the optimum disperser condition with varying dosage of alkyl polyglycoside. The maximum solubilization of 11% and suspended solid (SS) reduction of 8.42% were achieved at the disperser rpm, time, and surfactant dosage of 12,000, 30 min, and 12 μL. The alkyl polyglycoside-coupled disperser disintegration showed a higher biogas production of 125.1 mL/gCOD, compared to the disperser-alone disintegration (70.1 mL/gCOD) and control (36.1 mL/gCOD).

Nanoemulsion as an Effective Inhibitor of Biofilm-forming Bacterial Associated Drug Resistance: An Insight into COVID Based Nosocomial Infections

Antibiotic overuse has resulted in the microevolution of drug-tolerant bacteria. Understandably it has become one of the most significant obstacles of the current century for scientists and researchers to overcome. Bacteria have a tendency to form biofilm as a survival mechanism. Biofilm producing microorganism become far more resistant to antimicrobial agents and their tolerance to drugs also increases. Prevention of biofilm development and curbing the virulency factors of these multi drug resistant or tolerant bacterial pathogens is a newly recognised tactic for overcoming the challenges associated with such bacterial infections and has become a niche to be addressed. In order to inhibit virulence and biofilm from planktonic bacteria such as, Pseudomonas aeruginosa, Acinetobacter baumannii, and others, stable nanoemulsions (NEs) of essential oils (EOs) and their bioactive compounds prove to be an interesting solution. These NEs demonstrated significantly greater anti-biofilm and anti-virulence activity than commercial antibiotics. The EO reduces disease-causing gene expression, which is required for pathogenicity, biofilm formation and attachment to the surfaces. Essential NE and NE-loaded hydrogel surface coatings demonstrates superior antibiofilm activity which can be employed in healthcare-related equipments like glass, plastic, and metal chairs, hospital beds, ventilators, catheters, and tools used in intensive care units. Thus, anti-virulence and anti-biofilm forming strategies based on NEs-loaded hydrogel may be used as coatings to combat biofilm-mediated infection on solid surfaces.

Performance of Oleic Acid and Soybean Oil in the Preparation of Oil-in-Water Microemulsions for Encapsulating a Highly Hydrophobic Molecule

This work analyzes the dispersion of a highly hydrophobic molecule, (9Z)-N-(1,3-dihydroxyoctadecan-2-yl)octadec-9-enamide (ceramide-like molecule), with cosmetic and pharmaceutical interest, by exploiting oil-in-water microemulsions. Two different oils, oleic acid and soybean oil, were tested as an oil phase while mixtures of laureth-5-carboxylic acid (Akypo) and 2-propanol were used for the stabilization of the dispersions. This allowed us to obtain stable aqueous-based formulations with a relatively reduced content of oily phase (around 3% w/w), that may enhance the bioavailability of this molecule by its solubilization in nanometric oil droplets (with a size range of 30–80 nm), that allow the incorporation of a ceramide-like molecule of up to 3% w/w, to remain stable for more than a year. The nanometric size of the droplet containing the active ingredient and the stability of the formulations provide the basis for evaluating the efficiency of microemulsions in preparing formulations to enhance the distribution and availability of ceramide-like molecules, helping to reach targets in cosmetic and pharmaceutical formulations.