Berberis Vulgaris Fruit: Determination of Phenolic Compounds in Extracts Obtained by Supercritical CO2 and Soxhlet Methods Using HPLC.

Recently, research studies on nutraceutically important polyphenolic substances have attracted intensive attention. Berberis vulgaris is an important source of polyphenolic compounds and is often used in traditional medicine. In this study, the extraction of rutin and apigenin rich oil from Berberis vulgaris fruits was evaluated by supercritical carbon dioxide (Sc-CO2) extraction method with and without co-solvent. As valuable antioxidants, rutin and apigenin content of extracts were analyzed by HPLC, and their amounts were maximized via parametric optimization. The rutin compound studied in this research has the potential to be a drug against the COVID-19 virus. The operating conditions were considered in the range of 35-70 °C temperatures, 140-240 bar of pressures, 0.35-1.00 mm of mean particle sizes, 3-7 l/min of CO2 flow rates, and 0-8% w/w co-solvent. As a result of Sc-CO2 extractions, the amounts of rutin and apigenin were found as 173 ± 14.97 µg/g and 2.91 ± 0.11 µg/g, respectively, with the 8% (w/w) co-solvent addition. The amounts of rutin and apigenin obtained by Soxhlet extractions were found as 208.81 ± 8.48 µg/g and 6.55 ± 0.21 µg/g, respectively. When the Sc-CO2 method was compared with the Soxhlet method, it was seen that the fast and eco-friendly Sc-CO2 method was an ideal extraction method by providing 76.89% rutin and 44.53% apigenin recoveries. As a result of this study, the maximum extraction conditions for rutin and apigenin were obtained as 160 bar, 40 °C, 0.35 mm particle size, 3 l/min CO2, 8% w/w co-solvent ratio, and 120 min extraction period. Supplementary Information: The online version contains supplementary material available at 10.1007/s12161-021-02136-8.

Extraction and quantification of some valuable flavonoids from pinecone of Pinus brutia via Soxhlet and Supercritical CO2 extraction: a comparison study.

In this study, the extraction of oil from pinecone of Pinus brutia was evaluated by supercritical CO2 (Sc-CO2) and Soxhlet extraction methods. The quercetin, rutin and kaempferol (QRK) contents of oil were analyzed one by one via HPLC. The rutin compound investigated in this study has the potential to be a drug against the COVID 19 virus. SEM and BET analysis were performed to observe the structural change and increase in surface area after Sc-CO2 extraction. The operating conditions were investigated in the range of 35-65 °C temperatures, 140-220 bar of pressures, 0.30-1.00 mm of mean particle sizes, 3-7 l/min of CO2 flow rates, 0-8% w/w co-solvent and 30-150 min extraction periods. When the results obtained by the Sc-CO2 method were compared with the results of Soxhlet extraction method, the maximum recovery of total QRK was found 4.18% in co-solvent-free studies and 30.94% in co-solvent-added Sc-CO2 studies. Sc-CO2 extraction results of Q, R, and K were found as 14.75 ± 1.08 µg/g, 14.23 ± 1.27 µg/g, and 15.70 ± 1.13 µg/g pinecone, respectively. Soxhlet extraction results of Q, R, and K were found as 36.43 ± 2.26 µg/g, 57.19 ± 3.81 µg/g, and 50.80 ± 2.79 µg/g pinecone, respectively. The maximum amount of QRK was found as 44.68 ± 2.89 µg/g pinecone by Sc-CO2 method via adding 8% ethanol by mass and as 144.42 ± 5.39 µg/g pinecone by Soxhlet method. According to the reference Soxhlet method efficiency, the Sc-CO2 extraction recovery was found as 30.94%. Supplementary Information: The online version contains supplementary material available at 10.1007/s11696-021-01644-5.

Effect of Milling Time on Dry Sliding Wear Behaviors of Carbon Nanotubes Reinforced Al Matrix Composites.

In this study, the effect of mechanical milling time on microstructure, hardness and dry sliding wear behaviors of carbon nanotube reinforced aluminum matrix composites was investigated.Multi-walled carbon nanotubes (amount of 1%) were added to gas atomized AA7075 alloy as a reinforcement material and it was mechanical milled five different times. Milled Al-CNTs composite powders were added in a steel mold and pre-formed by cold pressing and hot pressing. Pre-formed composites samples were sintered. Microstructures of produced samples were examined by Scanning electron microscope. Density and hardness values were measured 1 ms-1 sliding speed, 30 N loads and five different sliding distances were used in dry sliding wear tests on pin on disc type wear apparatus. As a result of the studies, it was found that the particle size increased as the milling time increased. Powders milled for 100 min had the largest particle size, whereas powders milled for 120 min had a smaller particle size. The results indicated that composites mechanically milled for 120 min had both the highest hardness value and the lowest weight loss.

Effects of fly ash and boric acid on Y2O3-stabilized tetragonal ZrO2 dispersed with MgAl2O4: An experimental study on rat subcutaneous tissue.

The aim of this study was to evaluate the subcutaneous tissue reaction around zirconia-based materials. Forty-eight male Wistar Albino rats were used in this study. Disk-shaped (1mm height and 5mm diameter) samples composed of 67% spinel (MgAl2O4), 27% tetragonal zirconia polycrystal, 4% (m/m) fly ash and 2% (m/m) boric acid were inserted into dorsal muscles of rats. After 1, 4, 8 and 16 weeks, the animals were sacrificed and zirconia materials were removed with the surrounding tissue. Tissue sections were made with a microtome and then stained with hematoxylin and eosin. Sections were evaluated for the intensity of inflammation. Additionally, the somatic and visceral lymph nodes were evaluated. Data were submitted to one-way analysis of variance (ANOVA) and Tukey HSD tests at a significant level of p < 0.05. There were statistically significant differences between mean inflammatory scores in different experimental periods (p <0.05). In addition, the inflammatory reaction decreased over time. The tested materials had no damaging effect on the rat lymph nodes and did not have a toxic action on the internal organs. Therefore, zirconia polycrystal tested in the present study may offer a promising treatment alternative after further mechanical and biological studies are performed.

An approach to the usage of polyethylene terephthalate (PET) waste as roadway pavement material.

This study investigates an application area for Polyethylene Terephthalate (PET) bottle waste which has become an environmental problem in recent decades as being a considerable part of the total plastic waste bulk. Two novel additive materials, namely Thin Liquid Polyol PET (TLPP) and Viscous Polyol PET (VPP), were chemically derived from waste PET bottles and used to modify the base asphalt separately for this aim. The effects of TLPP and VPP on the asphalt and hot mix asphalt (HMA) mixture properties were detected through conventional tests (Penetration, Softening Point, Ductility, Marshall Stability, Nicholson Stripping) and Superpave methods (Rotational Viscosity, Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR)). Also, chemical structures were described by Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectrometer (EDS) and Fourier Transform Infrared (FTIR) techniques. Since TLPP and VPP were determined to improve the low temperature performance and fatigue resistance of the asphalt as well as the Marshall Stability and stripping resistance of the HMA mixtures based on the results of the applied tests, the usage of PET waste as an asphalt roadway pavement material offers an alternative and a beneficial way of disposal of this ecologically hazardous material.

Activation of pine cone using Fenton oxidation for Cd(II) and Pb(II) removal.

This paper describes activation of pine cone with Fenton reagent and determines the removal of Cd(II) and Pb(II) ions from aqueous solution. Changes of the surface properties of adsorbent materials were determined by the FT-IR and SEM analysis after activation of pine cone. The effect of Fe(2+)/H(2)O(2) ratio, ORP, pH and contact time were determined. Different adsorption isotherms were also obtained using concentrations of heavy metal ions ranging from 0.1 to 150mgL(-1). The adsorption process follows pseudo-first-order reaction kinetics and follows the Langmuir adsorption isotherm. The study discusses thermodynamic parameters, including changes in Gibbs free energy, entropy, and enthalpy, for the adsorption of Cd(II) and Pb(II) on activated cone, and revealed that the adsorption process was spontaneous and exothermic under natural conditions. The maximum removal efficiencies were obtained as 91% and 89% at pH 7 with 90 and 105-min contact time for Cd(II) and Pb(II), respectively.

Removal of trivalent chromium from water using low-cost natural diatomite.

Trivalent chromium was removed from the artificial wastewater using low-cost diatomite in batch and continuous systems. In batch system, four different sizes and five different amount of sorbent were used. The effect of the temperature on sorption was evaluated with using three different temperatures. As a result of the experiments, 85% of the trivalent chromium was removed from the wastewater in conditions of using 1.29mm grain material at 30 degrees C temperature for 60min in batch system but chromium removal was 82% at 30 degrees C temperature for 22min and 97% from the wastewater at 30 degrees C temperature for 80min in continuous system. Also, the equilibrium adsorption isotherms have been analyzed by Langmuir and Freundlich models. The Langmuir isotherms have the highest correlation coefficients. Langmuir adsorption isotherm constants corresponding to adsorption capacity, q0, were found to be 28.1, 26.5 and 21.8mg Cr3+/g diatomite at 15, 30 and 45 degrees C, respectively. Adsorption process was an exothermic process as a result of thermodynamic parameters calculations. The kinetic data of the sorption showed that the pseudo second-order equation was the more appropriate, which indicate that the intraparticle diffusion is the rate-limiting factor.

Influence of tall oil biodiesel with Mg and Mo based fuel additives on diesel engine performance and emission.

The purpose of this study is to investigate influences of tall oil biodiesel with Mg and Mo based fuel additives on diesel engine performance and emission. Tall oil resinic acids were reacted with MgO and MoO(2) stoichiometrically for the production of metal-based fuel additives (combustion catalysts). The metal-based additives were added into tall oil biodiesel (B60) at the rate of 4 micromol/l, 8 micromol/l and 12 micromol/l for preparing test fuels. In general, both of the metal-based additives improved flash point, pour point and viscosity of the biodiesel fuel, depending on the rate of additives. A single cylinder DI diesel engine was used in the tests. Engine performance values did not change significantly with biodiesel fuels, but exhaust emission profile was improved. CO emissions and smoke opacity decreased by 56.42% and by 30.43%, respectively. In general, low NO(x) and CO(2) emissions were measured with the biodiesel fuels.

Alternative fuel properties of tall oil fatty acid methyl ester-diesel fuel blends.

In this experimental work, tall oil methyl ester-diesel fuel blends as alternative fuels for diesel engines were studied. Tall oil methyl ester was produced by reacting tall oil fatty acids with methyl alcohol under optimum conditions. The blends of tall oil methyl ester-diesel fuel were tested in a direct injection diesel engine at full load condition. The effects of the new fuel blends on the engine performance and exhaust emission were tested. It was observed that the engine torque and power output with tall oil methyl ester-diesel fuel blends increased up to 6.1% and 5.9%, respectively. It was also seen that CO emissions decreased to 38.9% and NO(x) emissions increased up to 30% with the new fuel blends. The smoke opacity did not vary significantly.