Ethanol-water Solvent Research Articles

Gibbs Energy of the Transfer of Cryptand[2.2.2] from Water to a Water–Ethanol Solvent

Gibbs Energy of the Transfer of Cryptand[2.2.2] from Water to a Water–Ethanol Solvent

Green synthesis of benzimidazole derivatives using copper(II)-supported on alginate hydrogel beads

The study addresses the challenge of developing sustainable and efficient catalytic systems for the synthesis of benzimidazole derivatives, which are of significant importance in the field of medicinal chemistry due to their diverse biological activities. The objective is to develop a recyclable and environmentally friendly catalyst utilizing copper(II)-loaded alginate hydrogel beads, which can facilitate the synthesis of these compounds while minimizing environmental impact. The preparation process entails crosslinking sodium alginate with copper(II) ions to form hydrogel beads, which are then washed and characterized through techniques such as scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Inductively coupled plasma (ICP), and Zeta potential to analyses the morphology, composition and porosity of the beads. The catalytic performance is evaluated through recycling tests, which demonstrate the catalyst's ability to maintain selectivity and activity over multiple reaction cycles. The Cu(II)-Alg hydrogel beads were used for synthesizing substituted benzimidazole derivatives in a water-ethanol solvent at room temperature. This method offers significant advantages, including extremely mild reaction conditions, short reaction times (<1 h), high yields (70–94 %), and ease of processing. The most significant results indicate that the Cu(II)-alginate catalyst exhibits a high loading capacity and retains its catalytic efficiency for at least 3 cycles, thereby highlighting its potential for sustainable applications in organic synthesis.

OPTIMISATION METHOD FOR OBTAINING A BIOLOGICALLY ACTIVE SUBSTANCES FROM THE PLANT PETROSIMONIA BRACHIATA

Kazakhstan is rich in medicinal plants, so it needs to be studied. Ten species of the Petrosimonia belonging to the Chenopodiaceae family are growing in Kazakhstan. These plants have been adapted to harsh climatic conditions in the country’s salty, saline, and desert areas. Petrosimonia plants are a new species that has not been fully studied. Chinese scientists studied Petrosimonia sibirica species and found that the plant contains alkaloids, steroids, terpenes, flavonoids, and phenolic acids and has antibacterial activity (Wen, 2015; Ying, 2016). The qualitative and quantitative compositions of biologically active substances in P. sibirica, P. Glaucescens, P. triandra, and P. brachiata growing in Kazakhstan were studied. To prepare phytopreparations from P. Sibirica, P. Glaucescens and P. triandra plants were extracted using the classical maceration method, and individual representatives of biologically active compounds were isolated (Toktarbek, 2021; Seitimova, 2022). In this study, a phytochemical study of P. brachiata was conducted. The method for obtaining biologically active complexes with high efficiency was optimised by using supercritical fluid and ultrasonic extraction methods. These methods have a short extraction time, can be carried out at room temperature, are cost effective, and are a modern green chemical approach. Using supercritical fluid CO2 extraction (180 bar, 2 hours), the plant was purified from lipophilic substances. Further, a biologically active complex was obtained by pouring 70% ethanol-water solvent into the plant raw material and performing ultrasound extraction. The obtained complex was analysed by thin-layer chromatography using different organic solvent systems. Based on our analysis, steroids, terpenes, phenolic acids, and flavonoid glycosides were found in the extract. Hexane and ethyl acetate fractions were obtained as a result of liquid-liquid extraction of the extract using organic solvents. Stigmasterol 3-O-β-D-galactopyranoside, isovanillic acid, quercetin 3-O-β-D-glucopyranoside, and isorhamnetin 3-O-α-L-rhamnopyranoside were isolated by washing the hexane and ethyl acetate fractions in a silica gel column with an organic solvent system. The isolated compounds will be tested for biological activity.

Thermal insulating, flame retardant, and superhydrophobic polybenzoxazine/silica aerogels fabricated in water-ethanol solvent using eco-friendly method

Polybenzoxazine (PBz) aerogels have garnered considerable attention as an innovative and excellent thermal insulation material, celebrated for its lightweight, low thermal conductivity, and outstanding mechanical properties. However, the use of high boiling point toxic solvents in the preparation process requires a cumbersome solvent exchange procedure coupled with insufficient flame-retardant properties, which hinder the potential application of PBz aerogels. Herein, we employed tetraethyl orthosilicate (TEOS) into PBz using an easy, eco-friendly, and cost-less process to achieve hybrid structure polybenzoxazine/silica (PBz/SiO2) aerogels, by thermal catalysis (72 °C) ring-opening polymerization and polycondensation in water-ethanol solvent without any catalysts. The resulting PBz/SiO2 aerogels were characterized with low density (0.181 g/cm3), low thermal conductivity (0.0315 W/(m·K)), excellent flame-retardancy (PHRR value of 32.3 W/g and THR value of 6.3 kJ/g), and superhydrophobicity (the water contact angle up to 155°). Environment-friendly preparation strategy for the PBz/SiO2 aerogels with excellent comprehensive performance, poised to play a pivotal role in energy-saving buildings and fire-resistant applications.

Selective solid phase extraction of folic acid from tomato as a biological source with a magnetic molecularly imprinted polymer measured by fluorescence spectroscopy

AbstractA novel magnetic molecular-imprinted polymer (MMIP) was used to selectively extract folic acid directly from real samples. Folic acid was used as template molecule, Fe3O4/SiO2-3-triethoxysilyl-propyl-acrylamide as functional monomer, azobisisobutyronitrile as initiation, ethylene glycol dimethacrylate as crosslinker agent, and acrylamide as the secondary monomer in a mixed ethanol-water solvent. The effect of different parameters on the extraction efficiency was studied, and the optimum conditions were established as follows: the concentrations of crosslinking and template were fixed at 0.05 and 0.06 g, absorption percentage was 96.5, pH was adjusted to 8, and extraction time was 8 h with a temperature of 25 °C. By examining the effect of pH, we tried to investigate the effect of the amide groups that present in MMIP and its intermolecular hydrogen interaction with folic acid. After optimising the effective parameters in polymer synthesis and adsorption rate, a magnetic imprinting dispersive solid-phase extraction method combined with fluorescence spectrophotometry at λem = 367 nm (MMIP-DSPE-FL) was constructed for sensitive determination of folic acid in tomato samples. The limit of quantification (LOQ) and limit of detection (LOD) values were 30.00 ± 0.01 μg L−1 and 10.00 ± 0.03 μg L−1, respectively, after the MMIP-DSPE preconcentration. Three tomato samples were analysed to give recoveries in the range of 80.2–81.6%, with relative standard deviation values below 0.6% (n = 3). The prepared MMIP-DSPE showed high selectivity toward folic acid, which could be used six times without changing adsorption capacity. The adsorption isotherm of the folic acid-imprinted polymer pursued the Langmuir model (RL = 0.029), and the kinetics model followed pseudo-first-order (R2 = 0.9974).

The effect of solvent on the structural, morphological, optical and dielectric properties of SnO2 nanostructures

We investigate the effect of solvent, i.e., ethanol and deionized (DI) water, on the structural, optical, and dielectric characteristics of SnO2 nanostructures, synthesized via the hydrothermal method. Utilizing X-ray diffraction (XRD), we find the rutile phase for both nanostructures with average crystallite sizes of 12.53 nm and 6.62 nm for the samples synthesized using ethanol and DI water as solvents, respectively. The energy-dispersive X-ray spectroscopy (EDX) confirms the presence of Sn and O elements in both samples. Scanning electron microscopy (SEM) reveals that the samples prepared using ethanol and DI water exhibit nanorods and nanoflowers structures, respectively. The calculated band gap for SnO2 based on ethanol and DI water solvents is found to be 3.54 eV and 3.45 eV, respectively. The SnO2 nanostructure prepared by ethanol solvent demonstrates a higher dielectric constant which is attributed to higher defect density and more grain boundaries in it than in the sample synthesized using DI water. At low frequencies, the high tanδ values in the case of both nanostructures are explained based on space-charge polarization (SPC). The SnO2 prepared by DI water exhibits higher tangent loss than the one synthesized using ethanol because of its significant surface area. The significant amount of conducting grains in the SnO2 nanostructure while using ethanol solvent makes it a better conductive. Furthermore, the dielectric constant increases with increasing temperature which suggests considerable changes in the polarization behavior, while the tangent loss and conductivity demonstrate dependency on the temperature, indicating the promise of the nanostructures for electrical applications.

Dioscorea hispida (Dennst.) Tuber: Unraveling The Phytochemical Basis for Anthelmintic and Antifungal effects

Tropical diseases are prevalent ailments that manifest in tropical and subtropical regions in 149 countries. Various microorganisms, including bacteria, fungi, and worms, are responsible for the onset of tropical diseases. This infectious disease is frequently observed in nations with lower economic resources. The tubers of Dioscorea hispida possess the capacity to demonstrate anthelmintic and antifungal characteristics as a result of the existence of secondary metabolites. The tuber of Dioscorea hispida will undergo extraction followed by liquid-liquid fractionation using n-hexane, ethyl acetate, and ethanol-water solvents. The antifungal activity of the extracts and fractions was evaluated in vitro against Candida albicans and Trichophyton mentagrophytes for antifungal activity, and the anthelmintic activity was evaluated in vitro against Pheretima posthuma during paralysis and death for anthelmintic activity The extract Dioscorea hispida (Dennst) tuber showed good anthelmintic and antifungal efficacy; The phytochemical component in the ethyl acetate fraction had the highest performance at a concentration of 30 g/L with paralysis time of 23.90±2.94 and death time of 34.20±2.31 for anthelmintic, in line with that the ethyl acetate fraction also has antifungal activity which is strong at a minimum inhibitory concentration of 5 g/L with an inhibition zone diameter of 11.00 ± 0.40. The ethyl acetate fraction contains several metabolites, including alkaloids, flavonoids, glycosides, and tannins, which exhibit notable effectiveness as anthelmintics and antifungals.

Antioxidant Properties of Lemuni Leaves (Vitex trifolia var. purpurea) in Different Concentrations of Ethanol-Water Solvent Extraction

Vitex trifolia var. purpurea leaves (Lemuni leaves) is considered as a traditional medicine due to their antioxidant property. The antioxidant properties of Lemuni leaves depends on the concentration of ethanol-water solvent. Therefore, this current study intended to identify the antioxidant activity of Lemuni leaves (Vitex trifolia var. purpurea) in different concentrations of ethanol-water solvent extraction. Four ethanol-water concentrations were prepared (water extract (0% ethanol), 25% ethanol extract, 50% ethanol extract, and 75% ethanol extract). The antioxidant properties of Lemuni leaves were evaluated by Folin-Ciocalteu assay, aluminium chloride calorimetric method while 2,2’-diphenyl-1-picrylhydrazyl (DPPH) assay and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay were used to measure the antioxidant activities of the extracts. The experimental results showed that 75% ethanol extract had the highest (p&lt;0.05) total phenolic content (94.69 ± 4.75mg GAE/g DW) and total flavonoid content (30.76 ± 2.85mg QE/g DW) significantly. The 75% ethanol extract also had the significantly lowest (p&lt;0.05) IC50 value for DPPH (3.56 ± 0.11 mg/mL) and ABTS (2.01 ± 0.05 mg/mL) assays. Strong correlations were discovered between the total flavonoid content, total phenolic content with antioxidant properties of Lemuni leaves at different ethanol-water ratio by DPPH (r= -0.816; r= -0.824) and ABTS assays (r= -0.929; r= -0.920).The significantly elevated antioxidant properties of the 75% ethanol extract suggest promising applications in health supplements, pharmaceuticals, skincare products, biomedical research, and commercial ventures.

Investigation of the Functional Components in Health Beverages Made from Polygonatum cyrtonema Rhizomes Provides Primary Evidence to Support Their Claimed Health Benefits.

This study aims to understand the functional component compositions of traditional herbal health beverages made from Polygonatum cyrtonema rhizomes and to reveal the pharmacodynamic chemical basis for their claimed health benefits. Two traditional methods, rhizome decoction and rhizome infusion, were used to make health herbal beverages, including "Huangjin" tea and "Huangjin" wine, respectively. The secondary metabolites of "Huangjin" beverages were investigated and compared by widely targeted metabolomics. The results clearly showed that the major functional components in "Huangjin" beverages were phenolic acids, flavonoids, and alkaloids. The "Huangjin" wine has a greater variety of flavonoids and alkaloids than "Huangjin" tea, and the functional components in "Huangjin" wine were more abundant than those in "Huangjin" tea. Homoisoflavones and amide alkaloids were the dominating flavonoids and alkaloids in "Huangjin" wine, respectively. Continuous rhizome infusion could not increase the content of functional components in "Huangjin" wine. In conclusion, this study not only provides primary evidence to support the claimed health benefits of "Huangjin" beverages but also suggests that making traditional herbal beverages by rhizome infusion has superior health benefits than making them by rhizome decoction, which is attributed to the higher yields of functional components extracted by Chinese liquor than hot water. Therefore, Chinese liquor shows advantages in its use as a superior binary ethanol-water solvent in making herbal health beverages to enhance the solubility of poorly water-soluble functional components.

Nanostructures and multi-scale aggregation of high ion exchange capacity short-side-chain perfluorosulfonic acid dispersion

Short-side-chain perfluorosulfonic acid (SSC-PFSA) ionomers with high ion-exchange-capacity are promising candidates for high-temperature proton exchange membranes (PEMs) and catalyst layer (CL) binders. The solution-casting method determines the importance of SSC-PFSA dispersion characteristics in shaping the morphology of PEMs and CLs. Therefore, a thorough understanding of the chain behavior of SSC-PFSA in dispersions is essential for fabricating high-quality PEMs and CLs. In this study, we have employed multiple characterization techniques, including dynamic light scatting (DLS), small-angle X-ray scattering (SAXS), and cryo-transmission electron microscope (Cryo-TEM), to fully study the chain aggregation behaviors of SSC-PFSA in water–ethanol solvents and elucidate the concentration-dependent self-assembly process. In dilute dispersions (2 mg/mL), SSC-PFSA assembles into mono-disperse rod-like aggregates, featuring a twisted fluorocarbon backbone that forms a hydrophobic stem, and the sulfonic acid side chains extending outward to suit the hydrophilic environment. As the concentration increases, the radius of rod particles increases from 1.47 to 1.81 nm, and the mono-disperse rod particles first form a “end-to-end” configuration that doubles length (10 mg/mL), and then transform into a swollen network structure in semi-dilute dispersion (20 mg/mL). This work provides a well-established structure model for SSC-PFSA dispersions, which is the key nanostructure to be inherited by PEMs.

Nanoemulsions of red quinoa and ginseng extracts with chitosan wall: Investigating the antioxidant properties and its effect on the shelf life of dairy cream.

The study aimed to investigate the antioxidant properties of ginseng and red quinoa extract nanoemulsion and its effect on the shelf life of dairy cream. Nanoemulsion includes dairy cream, Tween 80, chitosan, whey protein powder, chitosan/whey protein powder, red quinoa extract, ginseng extract, and a mixture of extracts (1:1). The highest total phenol content and total flavonoid content were related to ginseng extract (24,009.55 mg of gallic acid equivalent/kg, 883.16 mg quercetin/kg) with ethanol-water solvent (80:20). Most of the phenolic and flavonoid compounds of ginseng and red quinoa extracts were related to p-coumaric acid (211.3 μg/g), catechin (29.6 μg/g), ellagic acid (73.88 μg/g), and rutin (34.12 μg/g), respectively. Considerable antioxidant power in the concentration of 800 ppm of red quinoa and ginseng extracts (ethanol-water solvent (50:50), (80:20)) in 2,2-diphenyl-1-picrylhydrazyl radical scavenging (80%, 82%, 80%, and 78%), bleaching β-carotene: linoleic acid (81%, 73%, 77%, and 86%), and ferric reducing antioxidant power assays (70%, 73%, 72%, and 76%) was observed. Nanoemulsions of red quinoa extract with chitosan wall had the smallest particle size (250.67 nm), the highest encapsulation efficiency (72.79%), and the polydispersity index (0.34). Nanoemulsions containing ginseng + quinoa (1:1) with chitosan/whey protein powder wall showed the highest viscosity (5.30 mPa/s) and the mostzeta potential (-32.6 mv). Also, nanoemulsions of red quinoa extract showed the lowest amount of peroxide value and the thiobarbituric acid value (12 milliequivalent O2/kg-0.48 μg/mL) in dairy cream oil. In general, the red quinoa extract with chitosan wall was superior to other samples due to the delay in oxidation and positive effect on the shelf life of dairy cream.

Toxicity Test of Red-Shoot Leaves (Syzygium myrtifolium Walp.) Extract as Biolarvicide on Filariasis Vector Mortality

The Control of Culex sp. using synthetic larvicides is harmful to the environment and human health. Biolarvicide from red shoot leaves (Syzygium myrtifolium) is a safe alternative for the environment and human health. This study aims to determine the effect of Syzygium myrtifolium leaves extract with ethanol solvent and water solvent on larval mortality and the LC50 values of these extracts. ANOVA test results (α = 0.05) on the mortality of Culex sp. larvae exposed to the ethanol extract and aqueous extract of S. myrtifolium leaves consecutively showed F-calculated (287)&gt;F-tabulated (3,11) and F-calculated (153)&gt;F-tabulated (3, 11). The treatment of S. myrtifolium leaves extract with ethanol and water solvents had a significant effect on the mortality of Culex sp. larvae. The LC50 value of the ethanol extract and the aqueous extract of S. myrtifolium leaves are 1659 ppm and was 2053.7 ppm. It can be concluded that S. myrtifolium leaves extracts with ethanol solvent and water solvent have an effect on the mortality of Culex sp. larvae, but are not yet effective as biolarvicide

Role of solvent on morphology and photoluminescence property of ZnO nano rods synthesized by hydrothermal method

Zinc oxide nano rods are synthesized by hydrothermal method. X ray diffraction studies confirm that the synthesized ZnO exhibited hexagonal wurtzite structure. The crystallite size is found to be 35 nm and 29 nm for the sample prepared from water-ethanol solvent mixture and water respectively. Transmission electron microscopic (TEM) images confirms that ZnO samples prepared from water solvent are nano rods, whereas samples prepared from ethanol-water mixture are agglomerated. Photoluminescence (PL) emission of the ZnO nano particles prepared from water solvent with peaks at 414 nm, 442 nm and broad emission at 555 nm. The sample prepared from ethanol-water mixture solvent exhibit broad emission at 500 nm.

Extraction of oxalic acid from porang tuber by mechanical separation method

Porang tuber is a source of food that has many benefits. It also has the disadvantage of increasing the risk of health problems because of its high oxalate content. One of the methods for capturing oxalic acid from porang tuber flour is the Mechanical Separation method. Porang flour was added to ethanol-water solvent with a ratio of the solvent mixture-porang flour and an ethanol-water composition according to the variable. The mixing of porang flour and the solvent mixture were heated and added with HCl. The filtrate obtained was taken and diluted. The diluted filtrate was taken and titrated using KMnO4. This study aims to examine the effect of material size (between 60 - 80 mesh, between 80 - 100 mesh, and &gt;100 mesh), the composition of the solvent mixture (60:40 v/v, 78:22 v/v, 96:4 v/ v), and the ratio of solvent with porang tuber flour (10:1, 15:1, 20:1) to oxalic acid yield in porang tuber flour. The results showed that the optimum conditions obtained from this RSM method are flour size of 100 mesh, composition of ethanol: water = 96:4, and the ratio of solvent to flour 20:1. Oxalic acid yield obtained in this variable is 30.2469%.

Conformational Space of the Translocation Domain of Botulinum Toxin: Atomistic Modeling and Mesoscopic Description of the Coiled-Coil Helix Bundle.

The toxicity of botulinum multi-domain neurotoxins (BoNTs) arises from a sequence of molecular events, in which the translocation of the catalytic domain through the membrane of a neurotransmitter vesicle plays a key role. A recent structural study of the translocation domain of BoNTs suggests that the interaction with the membrane is driven by the transition of an α helical switch towards a β hairpin. Atomistic simulations in conjunction with the mesoscopic Twister model are used to investigate the consequences of this proposition for the toxin-membrane interaction. The conformational mobilities of the domain, as well as the effect of the membrane, implicitly examined by comparing water and water-ethanol solvents, lead to the conclusion that the transition of the switch modifies the internal dynamics and the effect of membrane hydrophobicity on the whole protein. The central two α helices, helix 1 and helix 2, forming two coiled-coil motifs, are analyzed using the Twister model, in which the initial deformation of the membrane by the protein is caused by the presence of local torques arising from asymmetric positions of hydrophobic residues. Different torque distributions are observed depending on the switch conformations and permit an origin for the mechanism opening the membrane to be proposed.

Control of Liquid–Liquid Phase Separation, Nucleation, and Growth of L‐Menthol Single Crystals from Water–Ethanol Solvent Mixtures

AbstractL‐Menthol is a commonly used material in food production for flavor enhancement and fragrances, as well as in pharmaceuticals. However, during the solution crystallization process of L‐menthol, there is a major issue of oiling out or liquid–liquid phase separation (LLPS) in most organic solvents and their mixtures. The objective of the current work is to prevent the LLPS phenomenon and grow high‐quality single crystals of L‐menthol. A water–ethanol mixed solvent with nine different mixing ratios is used, ranging from 0.99W:0.01E to 0.91W:0.09E, through the conventional slow evaporation process. The findings indicate that the mixing composition of the solvent plays a significant role in the variation of solubility, refractive index, LLPS, nucleation, and crystallization. This is clearly demonstrated in the phase diagram. The occurrence of LLPS phenomenon, nucleation, growth behavior, and morphology of L‐menthol single crystals through optical microscopy is identified. Additionally, the internal structure and thermal stability of the grown polymorphs using PXRD, SCXRD, and DSC analyses are confirmed.

Hydrothermal liquefaction of oil-palm-derived lignin to bio-oils for use as antioxidants in biodiesel

Lignin extracted from oil palm empty fruit bunch (EFB) fibers was used to produce a phenolics-rich bio-oil via hydrothermal liquefaction in pure water, or an ethanol–water (1:1 v v−1) solvent system, in a stirred batch reactor. The effects of liquefaction temperature (200–300 °C), pressure (10–40 bar), reaction time (0.5–3 h), solvent-to-lignin mass ratio (5–20), and the type of gas (N2, H2, CO2) in the reactor headspace were investigated on the yield and antioxidant properties of the bio-oil. The bio-oil and other products were characterized in detail. The conditions for obtaining a high yield of a bio-oil with a maximum phenolics content and the antioxidant activity were the following: ethanol–water solvent system with a solvent-to-lignin mass ratio of 10, 250 °C, 40 bar, H2 in the headspace, and a reaction time of 2 h. The bio-oil product contained multiple phenolics compounds, and proved to be an effective antioxidant additive in biodiesel made from palm oil. The bio-oil produced under the above specified conditions was a superior antioxidant than butylated hydroxytoluene (BHT), an oxidant used commercially. The bio-oil produced using water as the solvent instead of ethanol–water, was a less effective antioxidant.

Blackcurrant Pomace as a Rich Source of Anthocyanins: Ultrasound-Assisted Extraction under Different Parameters

The industry is currently trying to manage the waste generated during juice pressing. Berry pomace is an especially rich source of many bioactive compounds. Blackcurrant pomace is particularly valuable because of the large amount of extractable anthocyanins remaining in the fruit skin. The aim of the study was to evaluate the effect of ultrasound-assisted extraction (UAE) parameters on the content of anthocyanins and color parameters of blackcurrant pomace extracts. The pomace used for the study was very rich in anthocyanins—an average content of 853.2 mg/100 g fresh weight. The effect of temperature (25, 35, 45 °C), time (15, 30, 60 min) and material/solvent ratio (1:20 or 1:7) on extraction yield was analyzed. The extracts were obtained using two solvents: water–ethanol acidified with HCl and water acidified with citric acid. Either solvent type, as well as the other parameters of the extraction process, have an impact on the level of anthocyanins in the extracts. The lowest range of extraction yield (63–68%) was obtained for a 1:7 ratio with water–citric acid solvent. The highest range of extraction yield (74–93%) was obtained for a 1:7 ratio with water–ethanol solvent. The most efficient method was extraction in a water–ethanol solvent (50/50 v/v) acidified with HCl, at a 1:7 material/solvent ratio, at 35 °C, for 15 min, providing 93% process efficiency. A strong relationship (r &gt; 0.991) was also found between anthocyanin content and color saturation (C*) or hue (h°) in the obtained extracts. Based on the E1% coloring strength results, all the extracts obtained can be considered strong colorants, especially those obtained with the water–citric acid solvent. Ultrasonic extraction can be successfully applied to extract pigments from blackcurrant pomace and obtain, for example, food coloring.

Microwave and Ultrasound-assisted Facile Synthesis of 2’-Hydroxychalcones

In this work, solvent-free microwave irradiation and ultrasonication in an ethanol-water solvent system were presented as viable methods for the synthesis of 2’-hydroxychalcones in a sustainable and facile way via base-catalyzed Claisen-Schmidt condensation from readily available 2’-hydroxyacetophenones and benzaldehydes. Additionally, the synthesis of 3-hydroxyflavone through in-situ oxidative cyclization of a 2’-hydroxychalcone intermediate in a one-pot, two-step approach under ultrasonication is also performed.

EFFECT OF ETHANOL-WATER CONCENTRATION AS EXTRACTION SOLVENT ON ANTIOXIDANT ACTIVITY OF Acalypha indica

Acalypha indica is an abundant and obtainable wild weed plant in Indonesia. This is a possible opportunity to enhance its utility. The effect of free radicals is one of the factors that contribute to oxidative stress in the body, which can lead to cell damage and trigger various diseases. Plants rich in antioxidants can inhibit free radical reactions and protect the body from oxidative stress. In this study, we conducted the identification of major metabolite compounds using UHPLC-Q-Orbitrap HRMS from 70% ethanol extracts of Acalypha indica. We also performed phytochemical and antioxidant activity tests with various concentrations of ethanol-water solvents including water, 30%, 50%, 70% ethanol, and absolute ethanol to determine the optimal extraction conditions and the influence of solvent concentration on the antioxidant activity of Acalypha indica extract. The results of UHPLC-Q-Orbitrap HRMS identification showed that the 70% ethanol extract of Acalypha indica contains 10 major compounds suspected to correlate with its antioxidant activity. These include five flavonoids compounds (palasitrin, vitexin 2"-o-p-coumarate, isorhamnetin 3- (3",6"-di-p-coumarylglucoside), peucenin, and sulfuretin), two amino acid compounds (2-amino-3-carboxymuconic acid semialdehyde and N-Acetyl-L-phenylalanine), two carboxylic acid compound (citric acid and traumatic acid), and one phenolic compound (quinic acid). Phytochemical tests show positive results for flavonoids, tannins, alkaloids, and triterpenoids in each of water, 30%, 50%, 70% ethanol, and absolute ethanol extracts. The best antioxidant activity was obtained from the 70% ethanol extract with an IC50 value of 47.064 ppm, categorizing it as an extremely strong antioxidant.