Propylene Glycol Solution Research Articles

Pharmacokinetics of intramuscular L-carvone in sheep.

To measure and model concentrations of the analgesic L-carvone, a natural component of spearmint, over time when administered IM to sheep and to characterize L-carvone's effects on CBCs and clinical biochemistry panels. L-carvone formulated as a 50% solution (v/v) in ethanol and propylene glycol was administered at 71.6 mg/kg IM, split between each semitendinosus muscle in 6 sheep. Venous blood was sampled over 24 hours, and plasma was separated by centrifugation. Additional blood was collected for CBC and serum biochemical analysis, and tissues were sampled after euthanasia. L-carvone concentrations in plasma and tissue homogenates were measured using HPLC-MS-MS. Plasma pharmacokinetic data were described using a nonlinear mixed effects model. Complete blood count and biochemistry data were compared to baseline values using repeated-measures ANOVA and Holm-Šidák tests (P < .05). Maximum plasma concentrations ranged from 0.28 to 1.93 µg/mL and occurred within 9 to 15 minutes after injection. Pharmacokinetics were best described using 2 compartments. Elimination half-life was 33.7 minutes and 390.2 minutes in the central and peripheral compartments, respectively. Mild increases in neutrophil count and significant increases in creatinine kinase and aspartate aminotransferase were associated with injection site myonecrosis. No physical examination, behavioral, or other clinically significant laboratory changes were noted. Intramuscular L-carvone exhibits rapid time to peak concentration, relatively slow plasma elimination, and low tissue concentrations after 24 hours. L-carvone exhibits a favorable pharmacokinetic profile for an analgesic drug. A new L-carvone formulation or administration route is needed to reduce inflammation and necrosis at the injection site.

The Method of Calculating the Heat Transfer Coefficient in the Heliosystems with Laminar and Transient Modes of Heat Carrier Flow Movement Structured Into Parts

In this study, a new method of choosing classical empirical equations for calculating heat transfer coefficients in the tubes of a shell-and-tube heat exchanger in the transient mode is proposed. This method is based on the fact that the flow is structured into a laminar boundary layer (LBL) zone and a turbulized part, and the heat transfer coefficient is calculated through the transient and turbulent heat conductivity, as well as the average thickness of the LBL and, accordingly, the average thickness of the rest of the coolant flow. At the same time, the key point of this method is the condition that the transient thermal conductivity of the LBL should be lower than the thermal conductivity of the turbulized part. If this condition is not fulfilled, it is concluded that the corresponding classical empirical equation is not suitable for calculating the heat transfer coefficient. A 45% aqueous solution of propylene glycol was taken as a model liquid, which can be widely used in solar collectors, in particular with nanofillers. This coolant is interesting because at a constant speed of V = 0.93 m/s, and the linear size (diameter) of the "live section" of the flow D = 0.021 m in the temperature range of 243–273 K it moves in the laminar mode, in the temperature range of 283–323 K — in transient mode and 333–353 K — in turbulent mode. A new formula is proposed for calculating the coefficient of turbulence of the coolant flow a, the numerical values of which are experimentally found in literary sources only for the air coolant.

Experimental investigation of thermophysical properties of propylene glycol based secondary fluids for ground source heat pumps and indirect refrigeration systems

More than 1.7 million ground source heat pumps are currently in operation in the European Union and a large majority of systems is using propylene glycol as secondary fluid. In this study the thermophysical properties of propylene glycol solutions with specific freezing points between −5 and −50 °C are investigated at low temperatures of interest for refrigeration and heat pump applications. The experimentally determined data are compared to a large number of data from the literature. It has been found that the freezing point results for all concentrations were in very good agreement with both Melinder (2010) and ASHRAE (2021) data. Moreover, the literature data and present study for concentrations above 40 wt-% have different density curve slopes compared to ASHRAE data. The viscosity results for concentrations below 40 wt-% were up to 21.5 % higher than ASHRAE data and the viscosity results for solutions with concentrations above 40 wt-% were lower by up to 9.7 %. The thermal conductivity results for concentrations above 40 wt-% were 10 % higher than ASHRAE (2021) data. The experimental specific heat capacity curves and other studies do not have the same linear trend as Melinder (2010) and ASHRAE (2021) data. This difference indicates that currently available ASHRAE data have been indirectly computed from thermal conductivity data or that they have not been fully experimentally validated. Finally, more studies are required to investigate concentrations below 25 wt-% to identify solutions with higher specific heat capacity than water that could be of interest for specific applications.

Investigation on recrystallization of cryoprotectant solutions during warming under alternating electric fields

In the field of cryopreservation, recrystallization during rewarming is a significant factor leading to cryo-injury, causing ice crystal-induced mechanical injury to biological samples. Currently, methods, such as adding ice recrystallization inhibiting agents and increasing warming rates, have been adopted to reduce recrystallization injury. These methods also greatly increase the potential toxicity risk and engineering difficulty of cryopreservation. Accumulating research has progressively demonstrated that application of an electromagnetic field during cryopreservation can influence the preservation efficacy. However, the mechanism of action of the electric field has remained a subject of ongoing debate. We observed the recrystallization phenomenon of cryoprotectant solutions under a polarized light microscope and discovered promising experimental results. The electric field strength did not exhibit a discernible impact on the ice crystal size, while electric field frequency exerted a more significant impact. We found that at specific frequencies, the ice crystal size and growing rate were significantly affected during annealing. Compared to no electric field, an alternating electric field with a voltage of 10 V and a frequency of 5 × 104 Hz increased the recrystallization areas of a 15% (w/v) propylene glycol solution by 57%. And an alternating electric field with a voltage of 3 V and a frequency of 5 × 108 Hz decreased the recrystallization area of a 0.9% (w/v) NaCl aqueous solution by 9.9%. Different types of cryoprotectants exhibit varying responses to alternating electric fields frequency. These findings prompt us to reevaluate the role and mechanism of alternating electric fields in the cryopreservation of biological materials.

The evaluation of L-arginine solution as a solvent for propolis extraction: The phenolic profile, antioxidant, antibacterial activity, and invitro bioaccessibility.

Ethanol has been widely used for the extraction of propolis. Due to its certain disadvantages, there has been an ongoing search to find alternative non-ethanolic extraction solvents. This study aimed to compare the phenolics, antioxidant, and antibacterial activity of propolis extracts prepared with 70% ethanol (EWE), propylene glycol (PGE), and L-arginine solution (BE). All extracts were subjected to an invitro simulated digestion procedure, and the phenolic profile of non-digested and digested samples was determined by using LC-MS/MS. Additionally, the change in total phenolic (TPC), total flavonoid content (TFC), and antioxidant capacities were determined at each digestion phase. TPC and TFC of non-digested propolis extracts had similar values, although BE showed higher antioxidant capacity (p < .05). The amount of TPC reached or transformed at the intestinal stage was higher for BE and PG compared to EWE. BE also provided the highest antioxidant capacity assay in digested samples. The most common phenolics were pinocembrin, pinobanskin, galangin, and CAPE in non-digested extracts. However, their concentration was drastically reduced by digestion, and their recovery (R%) ranged from 0% to 9.38% of the initial amount detected in the non-digested extracts. Chrysin was the most bioaccessible flavonoid in all extracts. Among phenolic acids, the highest R% was determined for trans-cinnamic acid (22.14%) from BE. All extracts showed invitro inhibitory activity against Escherichia coli and Staphylococcus aureus. This study suggests that an L-arginine solution could be used as an alternative solvent to ethanol and propylene glycol for propolis extraction.

Planar light induced fluorescence quenching oxygen diffusivity measurement near the gas–liquid interface in aqueous glycerol and aqueous propylene glycol

Experimental diffusivity data for gases in liquid mixtures are still scarce. To measure the diffusivity of dissolved oxygen in aqueous solutions of glycerol and propylene glycol, a planar light induced fluorescence (PLIF) method has been employed. The experimental method developed allows the measurement of the concentration field near the gas–liquid interface. The results show an increased oxygen diffusivity for the aqueous glycerol solution compared to the aqueous propylene glycol solution, corresponding to the lower viscosity of the solvent. Interestingly, during the first few seconds of oxygen absorption, a reduced early diffusivity is found for both experiments compared to later times. The results are compared with selected correlations and available experimental values. In general, the results are in good agreement with the literature data found and the discrepancy between early and later diffusivity is discussed.

Cryopreservation of rat embryos at all developmental stages by small-volume vitrification procedure and rapid warming in cryotubes

Intracellular ice formation during cryopreservation is lethal to the cell, including during warming. Here, we examined the effect of sample volume and warming rate on the cryopreservation success of 1-cell rat embryos based on successful development into blastocysts in vitro and to term in vivo following embryo transfer. Embryos were equilibrated in 5% propylene glycol solution for 10 min, held for 40 s at 0 °C in cryopreservation solution (5%PG + PEPeS), and cooled by immersion in liquid nitrogen. When 1-cell embryos were cryopreserved in a volume of 30–100 μL at a cooling rate of 5830–7160 °C/min and warmed at 35,480–49,400 °C/min by adding 1 mL of 0.3 M sucrose solution at 50 °C, 17.3–28.8% developed into blastocysts, compared with 57.0% of untreated embryos. However, when 1-cell embryos were cryopreserved in a smaller volume of 15 μl at 7950 °C/min and warmed at 68,850 °C/min, 58.8 ± 10.6% developed into blastocysts and 50.0 ± 7.4% developed to term, comparable to that of non-treated embryos (57.0 ± 5.4% and 51.4 ± 3.1%, respectively). Cryopreserved embryos at other developmental stages also showed high in vitro culture potential similar to that of the control. Using a conventional cryotube and a small-volume vitrification procedure with rapid warming, we achieved high levels of subsequent rat embryonic development at all developmental stages.

Design a geothermal bridge deicing system for an in-service bridge

Deicing on bridge deck surfaces is essential to ensure the safety and mobility of motorists during severe winter weather. Conventional snow/ice removal chemicals such as salt cause bridge corrosion and provoke environmental issues. Therefore, a new external geothermal heating system for bridge deck deicing and snow melting has been proposed, which can be installed onto in-service bridges. Conventional hydronic heating systems are developed based on the hydronic loops embedded inside bridge decks in the construction phase and have been studied by different research groups [1–3]. However, there is a greater need for deicing the in-service bridges. Therefore, an external heating system has been developed by attaching the hydronic loops to the bridge deck's bottom surface, which is usually covered completely with insulation materials such as geofoam, spray foam, and fiberglass [4]. To provide access to the bottom surface of the bridge deck for bridge inspection, a new external-geothermal hydronic heating panel system has been developed in this study.&#x0D; Studies on geothermal bridge heating systems mainly focused on energy analysis of the existing systems, thermal effects of control logic, and the development of models to simulate bridge heating systems neglecting the piping network. This study presents the design of a bridge external heating system for an in-service bridge located in the Dallas/Fort Worth Metroplex in North Texas, USA, to maintain high heating efficiency. The geothermal deicing system includes geothermal heat pumps, ground loops, and bridge loops. The required heat flux on the bridge deck surface to prevent ice formation is calculated based on the local weather data to determine the number of heat pumps. According to the total heating load determined from the design heat flux, geothermal water-to-water heat pumps are sized given the ground temperature profile and thermal conductivity test results. The pipe network is designed based on the target flow rate and standard parameters for pipe materials using Taco Hydronic System Solutions software. Figure 1 illustrates the heating system's schematics. Only one bridge span is shown in the figure. One bridge span includes four heating panels with a 6-inch gap between each panel as the access for bridge inspection. The control room hosts heat pumps, flow centers, manifolds, control, and monitoring instrumentation. The ground loop arrays are not shown in the figure.&#x0D; The deicing system design procedure consists of three phases: (1) selection of design weather condtions based on historical weather data, (2) calculation of the required heat flux on the bridge surface, and (3) sizing of ground loop heat exchangers (GHEs). The final design decisions stem from the integrations of the three phases. First, design weather conditions are selected based on realistic winter storm scenarios. Second, the required heat flux, 80 Btu/hr.ft2, on the bridge deck surface to prevent ice/snow formation is determined by considering previous design values, historical winter storms, and heat flux calculations by ASHRAE [5]. Lastly, based on the required heat flux, the GLHEs are sized using the design software GLHEPRo developed by Spitler et al. [6]. Inputs to the model, including the heating loads, the thermal recharge rates, a description of the ground thermal properties, a description of the borehole geometry, the fluid physical and thermal properties, and a description of the heat pump, are summarized in Table 1. The ground thermal properties are determined based on field thermal response tests. A 30% propylene glycol solution is specified as the heat transfer fluid. A borehole diameter of 15.24 cm, an HDPE single U-tube with a nominal diameter of 3.18 cm, and thermally enhanced grout are also specified.&#x0D; &#x0D; Aside from heating system design, pipe network design is critical to maintaining the target flow rate for every pipe branch. Therefore, pipe hydraulics is analyzed for pressure loss to ensure sufficient head pressure for the entire pipe network. This study evaluated piping network design based on target pressure loss and common design parameters such as pipe materials and installation types. The pipe network design results show that the final system consists of 4 heat pumps and 10 water pumps. Combinations of pipes in parallel and series are arranged for efficiency and operational safety. The heat pumps are designed to supply fluid to the bridge deck at approximately 38 ℃ with a total flow rate of 302.8 l/min. The borehole field configuration selected consists of 16 boreholes, each 91.5 m deep and a design flow rate of 18.92 l/min. The borehole field will supply fluid to the heat pumps at a minimum temperature of 18 ℃. The geothermal bridge deicing system is currently being installed onto the bridge and is expected to be completed by the summer of 2023.

Nanoparticle-releasing xerogel films prepared by a one-step method

Aggregation remains a challenge in the development of solid dosage forms of nanoparticles. Herein, we investigated whether xerogel films can allow sustained release of nanoparticles encapsulating curcumin (as a model drug) while preventing their aggregation. Such films can be fabricated by casting nano-oil droplets in an aqueous solution. In this study, curcumin and poly (lactic-co-glycolic acid) (PLGA) were dissolved in methylene chloride and emulsified in a polyvinyl alcohol (PVA)-propylene glycol (PG) solution. While drying the cast, the nano-oil droplets solidified to form nanoparticles. Concurrently, the PVA-PG solution was gelatinated and further dried to form a xerogel. The xerogel film containing curcumin-loaded nanoparticles disintegrated in vitro within 10 min, releasing the nanoparticles without aggregation. The emitted nanoparticles in turn released curcumin at a first-order rate over 90 min. Thus, xerogel films containing nanoparticles could be useful sustained-release solid preparations for delivering nanoparticles at a controlled rate without aggregation.

Improvement of the Method of Calculating Heat Transfer Coefficients Using Glycols Taking into Account Surface Forces of Heat Carriers

This study compares the classic calculating method of the heat transfer coefficients of the shell-and-tube heat exchanger tubes using the classic Nusselt, Reynolds, and Prandtl similarity numbers with a new method that takes into account the coefficients of surface tension of heat carriers, their transitional, turbulent viscosity and thermal conductivity, as well as the average thickness of the laminar boundary layer (LBL). The classic method shows a better efficiency of water as a heat carrier com-pared to a 45% aqueous solution of propylene glycol. Instead, the new calculation method shows that a 45% aqueous solution of propylene glycol at the same Rey-nolds numbers has higher heat transfer coefficients com-pared to water in the temperature range of 273–353 K. We divided the "live cross-section" of the flow of the liquid coolant into a medium-thick LBL, where the Fourier equation of thermal conductivity is applied, and into its turbulent part, where the equation of thermal conductivity with turbulent thermal conductivity is also applied. A new formula (14) is proposed for calculating the average thickness of the LBL based on the radius of the "live cross-section" of the coolant flow, as well as the Blturb similarity number obtained by us in previous works. A new formula (15) is also proposed for calculating the heat transfer coefficient, which includes the transitional and turbulent thermal conductivity of the corresponding zones of the flow "live section", as well as the average thickness of the LBL.

Insights into the formulation properties, biocompatibility, and permeability of poorly water-soluble methoxyflavones with PEG400 and propylene glycol.

Herein, thermal and non-thermal techniques were used to elucidate the putative physical and chemical interactions between poorly water-soluble Kaempferia methoxyflavones and PEG400/propylene glycol. Additionally, the biocompatibility of methoxyflavone-glycol solutions was evaluated using Caco-2 cells whereas the absorptive transport was investigated by measuring the apparent permeability coefficient (P app) of the methoxyflavones and transepithelial electrical resistance (TEER) of the Caco-2 cell monolayer. Data from differential scanning calorimetry, Fourier-transform infrared (FTIR), and proton nuclear magnetic resonance (1H NMR) spectroscopic analysis revealed physico-chemical compatibility between the three methoxyflavones and PEG400/propylene glycol. Furthermore, PEG400 and propylene glycol solutions of the methoxyflavones were shown to be compatible with Caco-2 cells at pharmacologically effective concentrations. In vitro transport studies across the Caco-2 cell monolayer revealed high P app values of 24.07 × 10-6 to 19.63 × 10-6 cm s-1 for PEG400 solutions of the methoxyflavones. The TEER values of the Caco-2 cell monolayers indicated that the increased drug transport was partly due to increased tight junction openings, but without compromising the epithelial barrier integrity. The good pharmaceutical and biocompatibility profiles, as well as improved transport of the methoxyflavones in PEG400 and propylene glycol solutions, are suggestive of the worthiness of this approach for further consideration pertaining to the development of these drugs into oral liquid dosage forms.

Analysis of the possibilities of increasing the energy efficiency of absorption refrigeration appliances through the use of refrigerating accumulators

One of the most important tasks of modern society is the solution of environmental and energy problems in power engineering and, in particular, refrigeration technology. At the same time, in the field of artificial cooling systems, it is necessary to solve the problems of reducing the impact on both the ozone layer and the greenhouse effect. An effective approach here can be absorption refrigeration systems with a natural working fluid (water-ammonia solution), which does not adversely affect the environment. For the effective use of absorption refrigeration systems, it is necessary to solve the problems of increasing their energy efficiency, in particular, through the use of cold accumulators. Thus, the object of research is absorption-type cooling systems with cold accumulators.&#x0D; The paper analyzes cold accumulators with different physical nature. It is shown that melting substances can be the most effective for solving problems of low-temperature cooling. An analysis of the thermal scheme of an absorption freezer of the «chest» type, which is the most problematic in terms of providing cooling modes at a level of (–18)–(–24) °С, was carried out. Optimization thermal calculations for typical absorption freezers up to 200 dm3 have been performed. It is shown that when the chamber is initially loaded with a product at an ambient temperature, the cooling capacity of the installed absorption refrigeration units is not enough – no more than 50 % of the required one. For an absorption freezer of the «chest» type, the most suitable cold-storage materials are a eutectic aqueous solution of sodium chloride or propylene glycol, since these solutions have the desired melting point of the order of –18 °C and a fairly high melting heat. The result of optimizing the weight and size characteristics of the internal volume of the absorption freezer is the following recommendations:&#x0D; – the optimal size of wire baskets for placing products is 315´370´240 mm;&#x0D; – the gaps between the basket and the cabinet wall, as well as between the baskets themselves, should be 10 mm to ensure normal convection conditions;&#x0D; – it is not advisable to place fans inside the volume of the freezer at this stage, since the freezing time is reduced by a maximum of 30 %, but this results in additional heat generation, energy consumption and increases the shrinkage of the products stored in the chamber.

Propylene glycol-mixed steam enhanced extraction for an efficient and sustainable remediation of PAHs-contaminated soil

An innovative thermal desorption method, propylene glycol (PG)-mixed steam enhanced extraction, is proposed for a highly efficient remediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soil. It is found that injecting PG-mixed steam into soil column could obtain > 99% removal efficiencies of PAHs either for the pyrene-spiked soil, or for the contaminated field soil with high-molecular-weight PAHs. PG is a safe and low-cost dihydric alcohol with a boiling point higher than water. When the PG-mixed steam penetrated the contaminated soil, the PG vapor preferentially condensed to form a hot liquid with concentrated PG (e.g., from 30 wt% PG in gas phase to 90 wt% PG in the liquid phase), which would significantly solubilize the PAHs and enhance their desorption from soils. The results also revealed that the effluents derived from the PG-mixed steam could be purified by removing the desorbed PAHs using a simple coagulation treatment, and the recovered PG solution could be reused. The plant assay using wheat seeds showed that the remediated soil had a good regreening potential. Our results demonstrate that PG-mixed steam injection is a promising thermal desorption method for an efficient and sustainable remediation of PAHs-contaminated soil.

Construction diversified morphologies of NiCo2O4 via tuning dielectric solvents as battery-type electrodes for supercapacitors

The construction of effective nano-microstructures electrode has been a tireless pursuit in the energy storage field. Herein, Controllable construction of diversified morphologies NiCo2O4 nanomaterials by tuning the dielectric constant and viscosity of the mixed solvent. We employed different solvent compositions as deionized water (DI), DI:Ethanol (1:1), DI: Isopropanol (1:1), DI: Propylene glycol (1:1), DI: Butanediol (1:1). In mixed aqueous solvents with low dielectric constants of ethanol and isopropanol, metal ions diffuse well and the nanomaterials tend to construct sheet-like nanostructures whereas high viscosity of the propylene glycol and butanediol solution will slow down the rate of metal ion diffusion, which only grow uni-directionally to form rod-like nanostructures. The formed ear-shaped NiCo2O4 nanostructures in Vpropylene glycol: VH2O = 1 : 1 mixed solvent have a large specific surface area and provide more electrochemically active sites, which facilitates effectively access electrolytes and thus accelerates the redox reaction rate. The resulting NiCo2O4 nanoears exhibits favorable capacity of 251 mAh g−1 and excellent rate performance with a 73.0% capacity retention at 20 A g−1. More importantly, the asymmetric supercapacitors assembled with the preferred NiCo2O4 nanoears and active carbon (AC) reveal excellent electrochemical performance at operating potential of 1.6 V, great specific capacity (58.0 mAh g−1), energy and power density of 46.4 Wh kg−1 at 801 W kg−1 and a specific capacity retention rate of 90.7% after 5000 cycles. This work provides a new perspective for the controllable construction of new micro-nanostructure materials.

Graphene Nanopowder and Propylene Glycol Solutions: Thermal and Physical Properties

Graphene Nanopowder and Propylene Glycol Solutions: Thermal and Physical Properties

Preparation and antibacterial properties of bismuth-rich Bi/Bi4O5I2 photocatalytic materials with surface defects

A series of bismuth modified bismuth iodide flower-like microspheres with rich oxygen vacancies were prepared by solvothermal method. Herein, a mixed solution of propylene glycol and ethylene glycol was used as the solvent. By adjusting the ratio of these two solutions in the solvent, it is not only possible to prepare Bi4O5I2 microspheres containing different concentrations of oxygen vacancies, but also to control the content of Bi. The Bi/ Bi4O5I2 photocatalyst prepared when the ratio of propylene glycol to ethylene glycol was 5:1 in solvent showed excellent optical properties, and more than 99% of E. coli could be inactivated within 30 min under visible light irradiation. The antibacterial mechanism experiment showed that reactive oxygen species were the main substances affecting the antibacterial effect of Bi/ Bi4O5I2, and the scavenging experiment of reactive oxygen showed that •O2- was the key active substance in the antibacterial process. Finally, it was verified that reactive oxygen species can act on the interior and exterior of bacteria, indicating a more effective antibacterial pathway.

Pharmacological justification of the composition of active ingredients in the composition of «Molozol» gel

Today, in connection with the rapid increase in the number of skin diseases complicated by secondary microbial and fungal infection, the creation of new drugs with a complex dermatomycosis effect for their local use is gaining particular relevance. In modern dermatological practice, mostly soft dosage forms are used. The wide use of soft medicinal forms is due to the presence of some advantages: high local concentration in the skin, relative economy and manufacturability of these means. However, on the modern Ukrainian pharmaceutical market, the range of drugs with a complex dermatomycosis effect is limited. This makes it necessary to find new means for local application in dermatitis with complicated fungal pathology.&#x0D; The aim of our research is an experimental ground of rational composition of operating substances in a gael under the conditional name «Molozol» for treatment of dermatomycoses. Gel was prepared on general rules by preparations of soft medical forms. Taking into account physical and chemical properties of operating substances, in particular their solubility, sucking, salicylic and sorbic acid was entered as a solution in propylene glycol and entered in the basis procured in advance for gel. With the aim of ground of rational concentration milk, salicylic and sorbic acid in the combined gel of «Molozol», and also study of his biological activity were conducted microbiological and toxicological.&#x0D; Determination of the antibacterial properties of the gel was carried out by diffusion in agar using reference strains of microorganisms Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 885/653.&#x0D; The rational composition of the active substances of the gel under the conventional name «Molosol» for the treatment of dermatomycosis was experimentally substantiated. Based on the data of microbiological studies, the concentration of active substances – lactic acid, salicylic acid and sorbic acid in the composition of the gel «Molosol» was justified. With the combination of active substances salicylic acid 8%, lactic acid 10%, for sorbic acid concentration 0.5%, «Molosol» gel shows the most pronounced antimicrobial and fungicidal activity against the tested strains of microorganisms.&#x0D; The index of acute toxicity when applied to the skin of animals was determined, which proved that the developed soft drug «Molosol» in the form of a gel belongs to the IV class of low-toxic substances.&#x0D; The combined gel «Molosol» is promising for further research as an antimicrobial and antifungal agent with keratolytic properties.

Phytochemical Compositions, Nutritional Contents, Cytotoxicity and Anti-Inflammatory Activity of Different Extracts from Spirogyra neglecta (Hassall) Kützing

Spirogyra neglecta (Hassall) Kützing is an edible freshwater macroalga. It is available and consumed as local food in Thailand, especially in the northern and northeastern parts. To ascertain its good benefit for health and safe for consumption, this study was, therefore carried out to determine the phytochemical compositions, nutritional contents, cytotoxicity, and anti-inflammatory activity of the different extracts from S. neglecta. The extracts were prepared by using different solvents, such as propylene glycol, methanol, and ethanol solutions. GC-MS analysis revealed the presence of 30, 39 and 36 phytochemical compounds in propylene glycol, methanol, and ethanol extracts, respectively. Phytol, which has been reported to have anti-inflammatory activity, was one of the predominant compositions in the extracts. The extracts contained high nutritional contents of protein, lipid, fiber, ash, moisture, and carbohydrate up to 21.68 ± 4.52, 3.53 ± 0.23, 14.77 ± 0.89, 10.73 ± 0.47, 9.79 ± 0.11 and 47.36 ± 3.89 %, respectively. The highest total protein was found in propylene glycol extract. The highest total lipid was in ethanol extract. Meanwhile, the highest fiber, ash and total carbohydrate were in methanol extract. In addition, all the extracts possess relatively low cytotoxicity, with IC50 values greater than 1,000 µg/mL. The extracts 1,000 µg/mL exhibited anti-inflammatory activity via inhibition Nitric oxide (NO) production by 29.87 ± 1.56 to 55.17 ± 1.91 %. The propylene glycol extracts from S. neglecta showed the highest inhibitory activity on NO production compared to others. The overall results indicating the propylene glycol is the solvent that produces the best extraction performance. The extracts from S. neglecta exhibit anti-inflammatory activity by inhibiting NO production. The phytochemical compositions are partly responsible for anti-inflammatory activity of the extracts. The high nutritional contents complement relatively low toxic. Thus, S. neglecta can be used as benefit natural sources for food products, supplements, and medicinal plants. HIGHLIGHTS Using GC-MS analysis, there are 30, 39 and 36 phytochemical compounds in propylene glycol, methanol and ethanol extracts from Spirogyra neglecta, respectively The extracts from neglecta possess high nutritional contents of protein, lipid, fiber, ash, moisture, and carbohydrate The extracts from neglecta show relatively low toxic to the RAW 246.7 cells with LC50 &gt;1,000 µg/mL, by MTT assay The extracts from neglecta exhibit anti-inflammatory activity by inhibition of NO production. The propylene glycol extract displays the highest activity compared to others The anti-inflammatory activity of the extracts is partially from Phytol GRAPHICAL ABSTRACT

Biological Impact of the Ratio of E-Cigarette Liquid Base Constituents, Propylene Glycol and Vegetable Glycerin, on Primary Human Melanocytes

Oral cavity is the first site to encounter e-cigarette (EC) or tobacco smoke. Increased gingival pigmentation can lead to aesthetic concerns and hinder successful outcomes of gingival depigmentation procedures as well as lead to color alterations in patients with dental restorations. While the effects of tobacco smoke and nicotine in increasing pigmentation in the gingiva of the smoker have been well-documented, the effects of EC on pigmentation have not been explored. Due to large variations in e-liquids from different sources, this study focused on the effects of EC liquid base constituents, propylene glycol (PG) and vegetable glycerin (VG), which are a universal constituent of all e-liquids. Effects of PG and VG solutions mixed at different ratios (0/100, 20/80, 55/45, 80/20, and 100/0 % v/v) were examined using primary human melanocytes obtained from neonatal foreskin; this cell model is representative of the physiological model of gingival melanocytes and has been used in our previous study. Results showed significant concentration-dependent cytotoxicity for all groups, although mixtures with higher PG content showed higher cytotoxicity to cells as compared to those with VG. Melanogenesis was robustly activated by PG-containing mixtures with the greatest effect obtained for 80/20 PG/VG mixture as compared to other ratios, while VG by itself did not activate melanogenesis. The activation of melanin synthesis within cells was not correlated to intracellular tyrosinase activity as that was suppressed by PG at higher ratios. Morphological changes of a multidendritic phenotype were observed in cells exposed to all PG/VG mixtures, with markedly greater effects for groups with higher PG content. Taken together, the results of this pilot study demonstrate for the first time that EC base constituents possess the capacity to significantly activate melanogenesis in human melanocytes at nontoxic concentrations, with the dominant effect obtained at a PG/VG ratio of 80/20, indicative of a nonlinear response with increasing concentrations of PG. Moreover, further studies to address the impact of PG/VG with the addition of nicotine and the effects of different EC flavors are underway. Future studies to elucidate mechanisms of increased pigmentation as well as further investigate effects in melanocytes with the presence of other oral cell types and other components of the oral microenvironment such as saliva and bacterial flora are warranted. This research emphasizes the need to reconsider the regulation of EC base constituents PG and VG as different ratios of these compounds can cause differential effects.

Gauging DNA degradation among common insect trap preservatives

AbstractGenetic methods for species identification are becoming increasingly popular and can accelerate insect monitoring. However, obtaining good DNA quality and quantity from insect traps remains a challenge for field studies. Ethylene glycol, propylene glycol, and Renner solution have been previously suggested as suitable preservatives for the collection of genetic material, but a systematic overview of their performance under compromising field conditions is lacking. Here we experimentally test whether and how different preservatives affect DNA quality under different conditions and evaluate how choice of preservative may affect metabarcoding and more demanding downstream applications (e.g., RADseq). For this, we used the house cricket, Acheta domesticus (L.) (Orthoptera: Gryllidae), and tested propylene glycol, ethylene glycol, and Renner solution for their ability to preserve DNA over 27 days in various dilutions and temperatures. DNA quality was measured as DNA fragmentation and success rates in PCR amplifying a COI fragment of 658, 313, or 157 bp. Undiluted propylene glycol and ethylene glycol always retained high molecular weight DNA at room temperature. No high molecular weight DNA was preserved at 37 °C or in any dilution. Nevertheless, the COI sequence could be amplified from samples at every condition. Renner solution did not preserve high molecular weight DNA and fragmentation increased over time at 37 °C until amplification was impossible. The results suggest that propylene glycol and ethylene glycol are suitable preservatives for collecting both genetic and morphological material, but dilution or high temperatures compromise their ability to preserve high molecular weight DNA. For genomic approaches requiring high DNA quality, additional preservatives may need to be tested.