Efficiency Of Different Solvents Research Articles

Comparative Static and Dynamic Analyses of Solvents for Removal of Asphaltene and Wax Deposits above- and below-Surface at an Iranian Carbonate Oil Field.

During production from oil wells, the deposition of asphaltene and wax at surface facilities and porous media is one of the major operational challenges. The crude oil production rate is significantly reduced due to asphaltene deposition inside the reservoir. In addition, the deposition of these solids inside the surface facilities is costly to oil companies. In this study, the efficiency of different solvents in dissolving asphaltene and wax was investigated through static and dynamic tests. The analysis of solid deposits from the surface choke of one of the Iranian carbonate oil fields showed that they consisted of 41.3 wt % asphaltene, and the balance was predominantly wax. In addition, the asphaltenes obtained from the surface choke solid deposits had a more complex structure than that of asphaltenes extracted from the crude oil itself. The static tests showed that xylene, toluene, gasoline, kerosene, and gas condensate had the highest efficiencies in dissolving solid deposits; conversely, diesel had a negative impact on dissolving solid deposits. Static tests on pure asphaltene showed that, among the tested solvents, gas condensate and diesel had a negative effect on the solubility of asphaltene. The dynamic core flooding results showed that asphaltene deposition inside the cores reduced the permeability by 79-91%. Among the tested solvents, xylene, gasoline, and kerosene resulted in the highest efficacy in restoring the damaged permeability, and higher efficiency was obtained with an equivalent solvent injection rate of 1 bbl/min versus 3 bbl/min.

Qualitative phytochemical screening of some selected medicinal desert species

Desert plants are considered as a rich source of secondary metabolites and are used in drug development. The main objective of the current investigation was to explore the secondary metabolite profile of some desert plants and also compare the efficiency of different solvents. Plants [Psidium guajava L., Thuja orientalis L., Callistemon citrinus (Curtis) Skeels, Capparis spinosa L. and Dipterygium glaucum Decne.] were collected from the Cholistan desert of Bahawalpur based on the traditional knowledge. Five types of extracts (petroleum ether extract, benzene extract, chloroform extract, ethanol extract and methanol extract) were prepared for both fresh and dry plant materials. The methanol extract showed the highest efficiency to detect the secondary metabolites as compared to that of all other extracts. Qualitative phytochemical analysis of these plants confirmed the presence of various important secondary metabolites, viz. phlobatannins, alkaloids, steroids, glycosides, flavonoids, terpenoids, quinones, anthocyanins, saponins, phenols, phytosterols and tannins in different parts (leaf, fruit, seed and whole plant). These results clearly show that potential bioactive compounds can be effectively extracted from important medicinal plants which could be potentially utilized by pharmaceutical industries.

Efficiency of Different Solvents in the Extraction of Bioactive Compounds from Plinia cauliflora and Syzygium cumini Fruits as Evaluated by Paper Spray Mass Spectrometry.

Jabuticaba (Plinia cauliflora) and jambolan (Syzygium cumini) fruits are rich in phenolic compounds with antioxidant properties, mostly concentrated in the peel, pulp, and seeds. Among the techniques for identifying these constituents, paper spray mass spectrometry (PS-MS) stands out as a method of ambient ionization of samples for the direct analysis of raw materials. This study aimed to determine the chemical profiles of the peel, pulp, and seeds of jabuticaba and jambolan fruits, as well as to assess the efficiency of using different solvents (water and methanol) in obtaining metabolite fingerprints of different parts of the fruits. Overall, 63 compounds were tentatively identified in the aqueous and methanolic extracts of jabuticaba and jambolan, 28 being in the positive ionization mode and 35 in the negative ionization mode. Flavonoids (40%), followed by benzoic acid derivatives (13%), fatty acids (13%), carotenoids (6%), phenylpropanoids (6%), and tannins (5%) were the groups of substances found in greater numbers, producing different fingerprints according to the parts of the fruit and the different extracting solvents used. Therefore, compounds present in jabuticaba and jambolan reinforce the nutritional and bioactive potential attributed to these fruits, due to the potentially positive effects performed by these metabolites in human health and nutrition.

Studies on red-pigment production by Talaromyces atroroseus TRP-NRC mutant II from wheat bran via solid-state fermentation

Background Recently, the need of finding eco-friendly and less-hazardous pigments focused on an important alternative to harmful synthetic dyes. High productivity of various pigments from microorganisms, their rapid growth throughout the year, stability, and solubility of their pigments provide them advantages more than pigments produced from other natural sources.Objective The objective of this study is to improve red-pigment production from local isolated fungus Talaromyces atroroseus TRP-NRC on an inexpensive substrate (wheat bran) under solid-state fermentation system by using different mutants. Then, comparing between pigment released from fungi after mutation by different mutants, comparing the efficiency of different solvents for the extraction of red biopigments under different conditions, and then extraction of pigment and studying its structure.Materials and methods A novel locally non-mycotoxin-producing fungus T. atroroseus TRP-NRC was treated with γ-ray radiation followed by subjecting to ultraviolet rays and grown on wheat bran as a complete medium via solid-state fermentation technique. Different solvents, including water, ethanol, methanol, and acetone, were applied to extract pigment from dried fermented wheat bran. The effect of pH, temperature, and contact time on yield of pigment extraction was studied. Stability of extracted pigment to heat, autoclaving, and ultraviolet rays was studied. Antimicrobial activity of extracted pigment was studied. The extracted sample was subjected to high-performance liquid-chromatography analysis and gas chromatography–mass spectrometry analysis. Statistical analyses were performed using SPSS program at P value less than 0.05.Results and conclusion The mutant fungus (I) by gamma radiation achieved 30% increase in red pigment compared with the wild type. The mutant fungus (I) was subjected to ultraviolet rays, mutant (II) added 22% increase in pigment production compared with mutant obtained by gamma radiation. About 70% v/v of methanol, ethanol, and acetone were more efficient for extracting pigment with an advantage of 70% v/v acetone. The yield of pigment extraction was affected by pH, temperature, and contact time, and was at pH 6.5 at 50°C after 16 h. The produced pigment appeared to be heat-stable when subjected to heat from 30 to 80°C for 6 h. The pigment was also stable when autoclaved at 121°C for 15 min. The pigment was stable when subjected to ultraviolet rays for 6 h. The extracted pigment showed antibacterial activity against Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative). Gas chromatography–mass spectrometry analysis revealed that eighteen compounds were identified in the acetone extract of pigment. In general, the prevailing two compounds of fermented wheat bran by T. atroroseus TRP-NRC mutant-II extract were 9, octadenoic acid (43.72) and 1,1′-bicyclopropyl-2-octanoic acid, 2′-hexyl-, methyl ester 43.72%.

Surfactant-mediated extraction of capsaicin from Capsicum annuum L. fruit in various solvents

Capsaicin is a valuable compound found in Capsicum annuum. The present study aimed to explore the efficiency of different solvents and surfactants on its extraction by maceration. Ethyl acetate was found to be the best solvent followed by dichloromethane and acetone, respectively. Overall order of efficiency of the solvents used was this: ethyl acetate > dichloromethane > acetone > glycerol > acetonitrile > methanol > acetic acid > toluene. Extractability of ethyl acetate for capsaicin remained unaffected by the surfactants. Tween-80 had very positive effect on the extraction efficiency of dichloromethane (DCM) and acetone. Kinetics of the extraction with the most efficient solvent ethyl acetate showed extraction of capsaicin to follow a pseudo-second order kinetic model. In conclusion, for extraction of capsaicin from green chili, ethyl acetate was the most powerful amongst the solvents used in the present work and tween-80 had a notable positive effect on the efficiency of DCM and acetone.

Application of Ultrasound-Assisted Extraction and Non-Thermal Plasma for Fucus virsoides and Cystoseira barbata Polysaccharides Pre-Treatment and Extraction

Brown algae Fucus virsoides and Cystoseira barbata are an abundant source of sulfated polysaccharide fucoidan, which has shown a wide range of biological activities. These activities are significantly dependent on the fucoidan chemical composition, which is closely linked with the applied extraction technique and process parameters. In order to overcome the drawbacks of lengthy conventional extraction (CE), advanced extraction techniques, such as ultrasound-assisted extraction (UAE) and non-thermal plasma (NTP), were applied. Furthermore, this study also investigated the efficiency of different solvents as well as UAE and NTP as 5 min pre-treatments prior to CE as a more effective course of cell wall breakage and, consequently, a higher polysaccharide yield (%PS). Apart from %PS, the effect of this procedure on the chemical composition and antioxidant capacity of the extracted polysaccharides was also monitored. When comparing the extraction solvent, the application of 0.1 M H2SO4, instead of H2O, resulted in a three-fold higher %PS, a higher sulfate group, and a lower fucose content. Application of CE resulted in higher %PS, uronic acids, and fucose content as well as oxygen radical absorbance capacity (ORAC) and DPPH values, while the average molecular weight (Mw), sulfate group, and glucose content were lower during CE when compared to 30 min of UAE and NTP treatment. Application of UAE and NTP as 5 min pre-treatments decreased fucose content, while %PS and sulfate content were similar to values obtained when using CE.

Assessing the efficiency of different solvents for detecting gliotoxin from soil, organic manures and crop plant

ABSTRACT Trichoderma virens produces gliotoxin and it is considered as a potent antibiotic against several soil-borne fungal and bacterial pathogens infecting crop plants. There is no study on the fate of gliotoxin especially its persistence in soil and crop plants. For precise analysis of its persistence, dissipation and movement of gliotoxin in soil ecosystem, it is important to find a suitable solvent that effectively extract the gliotoxin from soil and crop plant. In this study, various commonly used polar and non-polar solvents were assessed for their efficiency on extraction of gliotoxin from agricultural soil, farm yard manure (FYM), coir pith, tomato plants and from the mycelial mat of T. virens. Chloroform was found to be the effective solvent for the extraction of gliotoxin from soil, FYM and coir pith with extraction efficiency of 85%, 79% and 72%, respectively. Ethyl acetate extracted the maximum amount of gliotoxin from tomato leaves and roots with 79% and 72% extraction efficiency. Methanol effectively extracted gliotoxin from the mycelium of T. virens. From this study, it is concluded that chloroform and ethyl acetate are suitable for the extraction and detection of gliotoxin from the soil ecosystem and crop plants, respectively.

Optimization of Extraction of Bioactive Compounds from Baphicacanthus cusia Leaves by Hydrophobic Deep Eutectic Solvents.

Deep eutectic solvents (DESs) are considered as efficient and green solvents for the extraction of bioactive compounds from medicinal plants. In this work, a novel method of DES-based ultrasound-assisted extraction of bioactive compounds from Baphicacanthus cusia leaves (BCL) was established. Systematic screening and the morphology of the original and treated BCL were observed with scanning electron microscopy to determine the extraction efficiency of different solvents. The extraction conditions were optimized by Box–Behnken design (BBD) tests and the optimal extraction conditions were as follows: lactic acid/L-menthol ratio of 5: 2 (mol/mol), solid–liquid ratio of 80.0 mL/g and temperature of 60.5 °C. The extraction yields of tryptanthrin, indigo and indirubin reached 0.356, 1.744 and 0.562 mg/g, respectively. The results of a 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity test indicated the feasibility of DESs in the extraction of bioactive compounds. This study indicated that L-menthol/lactic acid was a green and efficient solvent for the extraction of bioactive compounds from BCL, and DES-based ultrasound-assisted extraction could be used as an effective application strategy for the extraction of bioactive compounds from medicinal plants.

Experimental determination and modeling of liquid-liquid equilibrium for ternary mixtures composed of water, epichlorohydrin and different solvents

Liquid-liquid equilibrium (LLE) data for water + epichlorohydrin + {chloroform or isopropyl ether or methyl tert-butyl ether or isopropyl acetate or ethylacetate or 2-ethyl-1-hexanol} systems at 308.2 K under 101.3 kPa were determined. The distribution coefficient and the separation factor were used to judge the extraction efficiency of different solvents on epichlorohydrin removal from water. The Othmer-Tobias, Hand, and Bachman equations were applied to check the reliability of the experimental LLE data. Furthermore, the experimental LLE data were successfully correlated with the NRTL and UNIQUAC models with all the RMSD values were less than 0.57%.

Comparative efficiency of different solvents for the anthocyanins extraction from chokeberries and black carrots, to preserve their antioxidant activity

Anthocyanins occur naturally in many blue-, purple- and red-colored fruits and vegetables, and are commonly found in the human diet as natural colorants with proven health benefits. This work aimed to find the most efficient solvents for the anthocyanins extraction from natural matrices (chokeberries and black carrots), able to preserve their antioxidant activity. Four different acidified solvents (methanol, ethanol, acetone, and water) were tested and the extracts were characterized by UV–Vis spectroscopy and High-Performance Liquid Chromatography coupled with Mass Spectrometry. The anthocyanins profile of each extract has been identified. Five monoglycosylated anthocyanins were found in chokeberries and ten anthocyanins (four acylated and four diglycosylated) in black carrots. The antioxidant activities of all extracts (using ABTS, CUPRAC and FRAP assays) were determined concomitantly and ranked. The most efficient extraction was obtained using ethanol and methanol, such extracts showing the highest antioxidant activity for both matrices (black carrots and chokeberry).

Evaluation of Various Drying Methods on Bioactives, Ascorbic Acid and Antioxidant Potentials of Talinum triangulare L., foliage.

The aim of this study was to assess the efficiency of different drying methods (room, sun, oven, microwave, cross-flow, infra-red, dehumidifier, and freeze-drying) on maximum retention of the nutritional and bioactive compounds profiling of Talinum triangulare, which is a less-known perishable leafy-vegetable. The evaluation of various drying methods is to learn the best appropriate strategy for a post-harvest drying method for retaining all the potential benefits with minor loss. Microwave and freeze-dried samples held the maximum ascorbic acid quantified by HPLC with 1.36 and 1.11g/100g DW, respectively. The main carotenoid compounds identified were violaxanthin, lutein, zeaxanthin, β-carotene isomers, trans-β-carotene, and cis-β-carotenes. Gallic, protocatechuic, catechin, para-coumaric, ferulic, rutin, trans-cinnamic, and quercetin are the significant phenolics and flavonoids identified and quantified by liquid chromatography. The efficiency of different solvents on bioactive extractions uncovered that the methanol and 80% aqueous ethanol were good for retention of total phenolics, total flavonoids, and antioxidant compounds, which was affirmed through phosphomolybdate, DPPH, and FRAP assays. Dried T. triangulare foliage could be productively utilized as a promising raw material for food and pharma businesses because of its rich bioactive composition.

Quantification of co-, n-, and ad-lupulone in hop-based dietary supplements and phytopharmaceuticals and modulation of their contents by the extraction method

Hop β-bitter acids (lupulones) are health-beneficial components of Humulus lupulus L. showing, for example, antidepressant-like effects in vitro. Despite of the widespread use of hops for medicinal purposes, the concentrations of lupulones in hop-based drugs have not been reported yet. The present study developed, validated, and applied a method with external calibration, which allows for the first time separate quantification of co-, n-, and ad-lupulone in hop-based drugs by UHPLC‒DAD. Concentrations between ‘not detectable’ and 2.7 mg/mL co-lupulone, 2.2 mg/mL nlupulone, or 0.7 mg/mL ad-lupulone were measured in nine different commercial dietary supplements and phytopharmaceuticals. Only one hop tincture contained sufficient lupulone to possibly exert potential antidepressant effects. Aiming for products with increased lupulone content, the extraction efficiency of different solvents was investigated. Complete extraction of lupulones from raw hops was achieved by organic solvents including methanol and ethanol, whereas aqueous mixtures resulted in low recovery. These results indicate that adapted extraction conditions may result in more effective hops products.

Optimisation of mint active compound extraction with anti-muscarinic property on intestine tissue

Muscle spasms may occur when muscle is overused and tired, particularly if it is overstretched or if it has been held in the same position for a prolonged period of time. Menthol, an anti-spasmodic, is a natural ingredient found in mint (Mentha piperta). This research was aimed, to determine the efficiency of different solvents for menthol extraction through antimuscarinic effect on frog ileum smooth muscle and to determine the optimal menthol concentration for anti-muscarinic effect. Dried mint leaves were ground into powder and compounds were extracted using methanol, ethanol and acetone, all at 100% v/v, 75% v/v and 50% v/v concentration. These extracts at doses ranged from 0.0–3.0 mg/mL were tested on 3cm frog smooth muscle to observe the anti-muscarinic effect. The extraction of menthol was significantly higher in acetone (3.43cm ± 0.23) compared to methanol (3.23cm ± 0.13) and ethanol (3.22cm ± 0.12), p<0.001. Based on the dose response curve, the minimal effective concentration for acetone to produce maximum relaxation was 1.0 mg/mL which higher when compared to positive control, atropine (3.30cm ± 0). In conclusion, acetone mint extract demonstrated significant anti-muscarinic property in smooth muscle relaxation at 1mg/mL comparable to atropine drug.

Extraction Efficiency of Different Solvents and LC-UV Determination of Biogenic Amines in Tea Leaves and Infusions.

Biogenic amines (BAs), that is, spermine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine, cadaverine, and serotonin, have been determined in several samples of tea leaves, tea infusions, and tea drinks by LC-UV method after derivatization with dansyl chloride. Different extraction solvents have been tested and TCA 5% showed better analytical performances in terms of linearity, recovery percentages, LOD, LOQ, and repeatability than HCl 0.1 M and HClO4 0.1 M and was finally exploited for the quantitative determination of BAs in all samples. In tea leaves total BAs concentration ranged from 2.23 μg g−1 to 11.24 μg g−1 and PUT (1.05–2.25 μg g−1) and SPD (1.01–1.95 μg g−1) were always present, while SER (nd–1.56 μg g−1), HIS (nd–2.44 μg g−1), and SPM (nd–1.64 μg g−1) were detected more rarely. CAD and PHE were determined in few samples at much lower concentrations while none of the samples contained TYR. Tea infusions showed the same trend with total BAs concentrations never exceeding 80.7 μg L−1. Black teas showed higher amounts of BAs than green teas and organic and decaffeinated samples always contained much lower BAs levels than their conventional counterparts.

Cleaning of biomaterial surfaces: Protein removal by different solvents

The removal of biofilms or protein films from biomaterials is still a challenging task. In particular, for research investigations on real (applied) surfaces the reuse of samples is of high importance, because reuse allows the comparison of the same sample in different experiments.The aim of the present study was to evaluate the cleaning efficiency of different solvents (SDS, water, acetone, isopropanol, RIPA-buffer and Tween-20) on five different biomaterials (titanium, gold, PMMA (no acetone used), ceramic, and PTFE) with different wettability which were covered by layers of two different adsorbed proteins (BSA and lysozyme). The presence of a protein film after adsorption was confirmed by transmission electron microscopy (TEM).After treatment of the surfaces with the different solvents, the residual proteins on the surface were determined by BCA-assay (bicinchoninic acid assay). Data of the present study indicate that SDS is an effective solvent, but for several protein–substrate combinations it does not show the cleaning efficiency often mentioned in literature. RIPA-buffer and Tween-20 were more effective. They showed very low residual protein amounts after cleaning on all examined material surfaces and for both proteins, however, with small differences for the respective substrate–protein combinations. RIPA-buffer in combination with ultrasonication completely removed the protein layer as confirmed by TEM.

Effect of pre-treatment on solvents extraction and physico-chemical properties of castor seed oil

Extraction of castor oil from castor seed was carried out by Soxhlet method using polar and non-polar commercial solvents at the optimum conditions obtained from the preliminary oil extraction study. The solvents used were hexane, pentane, petroleum ether, cyclohexane, ethylacetate, methanol, and isopropanol. The effect of different process parameters such as temperature, solute to solvent ratio, and extraction time were studied to optimize and compare the extraction efficiency of different solvents. The higher oil yields of 56.07% and 55.22% were obtained by using polar solvents, i.e., ethyl acetate and methanol, respectively. The physico-chemical properties of the castor oil extracted using different solvents were also estimated to determine its quality potential using ASTM methods. Similarly, the performance of seed pre-treatment on the oil yield and the suitability of methanol as a possible extracting and reactive solvent for biodiesel production was also investigated. The pre-treatment of castor seed has slightly increased the oil yield and decreased the values of acid value (3.92 to 0.925 mg KOH/g) and pour point (−15 to −21 °C) significantly. Apart from that, thermal and oxidative stability analysis was performed using thermo gravimetric analysis and differential scanning calorimetry under nitrogen and air atmosphere, respectively. The fatty acid profile of castor oil was determined by using gas chromatography. The 1H nuclear magnetic resonance spectroscopy was employed for two castor oil samples (extracted after and before heat-treatment of seeds) to compare and identify the different protons in present the oil. The obtained physico-chemical properties indicate that oil meets the prescribed biodiesel feedstock quality standards and further justifying that methanol can be a capable solvent for simultaneous extraction and transesterification.

Phenolic Profiling and Evaluation of Contraceptive Effect of the Ethanolic Extract of Salsola imbricata Forssk. in Male Albino Rats.

Reported researches dealing with either composition or bioactivity of Salsola imbricata are limited. This study was conducted aiming to investigate the phenolic composition of the plant and evaluate its efficacy as male contraceptive. Polyphenols, namely, phenolic acids and flavonoids, were qualitatively and quantitatively analysed by RP-HPLC in the hydrolysed methanol extract using two different wavelengths, 280 and 330 nm. The efficiency of different solvents in extracting the plant phenolics was assessed via spectrophotometric determination of the total phenolic and flavonoid contents. Acute toxicity study was carried out on the ethanolic extract to ascertain its safety prior to biological evaluation. The contraceptive effect was assessed, in male rats, by oral administration of the extract at two doses (250 and 500 mg/kg b. wt.), over a period of 65 days. HPLC analyses allowed the identification and quantification of a total of 13 and 8 components in the hydrolysed-methanol extract; the overall phenolic composition was dominated by quercitrin (12.692%) followed by coumaric acid (4.251%). Prolonged oral administration of the ethanolic extract caused slight reduction in the testis weight only. A significant decrease in the sperm count was observed (P < 0.01) in the two treated groups while significant decrease in the epididymal sperm motility was only observed in the high dose group. Morphological abnormalities were observed in sperms of treated animals. No distinct change in serum FSH, LH, and testosterone concentration was recorded. The histopathological findings supported to a high extent these results. The male contraceptive activity of Salsola imbricata could be ascribed to its phenolic components, especially quercitrin.

Efficiency of Different Solvents on the Extraction of Bioactive Compounds from the Amazonian Fruit Caryocar villosum and the Effect on its Antioxidant and Colour Properties

ABSTRACTIntroductionCaryocar villosum has been reported as a source of bioactive compounds that can be used as a potential product against oxidative damage in foods or biological systems.ObjectiveTo obtain extracts from fruit pulps of C. villosum with high levels of bioactive compounds that have both antioxidant and colour properties.MethodThe contents of bioactive compounds (total phenolic compounds, flavonoids, tannins, carotenoids and tocopherols), the colour parameters, the scavenging capacity against peroxyl radicals (ROO•) and the quenching activity against singlet oxygen (1O2) were determined. All data were used for extract classification by applying principal components analysis and hierarchical cluster analysis.ResultsThe water and ethanol:water (1:1, v/v) extracts presented the highest levels of total phenolic compounds (9.2 and 6.3 mg gallic acid equivalent/g extract, respectively), total flavonoids (3.8 and 2.5 mg catechin equivalent/g extract, respectively) and total tannins (7.6 and 2.4 mg tannic acid equivalent/g extract, respectively). The ethanol:water (1:1, v/v) extract also showed the highest scavenging capacity against ROO• (0.3 mmol trolox equivalent/g extract) and the highest protection against 1O2 (12.5%). On the other hand, the ethanol extracts, which were the most vivid and yellow colour (C*ab = 13.7 and b* = 13.3), presented the highest level of total carotenoids (0.1 mg/g), but low scavenging capacity against ROO• (0.01 mmol trolox equivalent/g extract).ConclusionBased on these results and depending on the applicability, the ethanol:water, water and ethanol are the most promising solvents to obtain C. villosum extracts with high contents of bioactive compounds, ROO• scavenging capacity and protection against 1O2. Copyright © 2013 John Wiley &amp; Sons, Ltd.

Development of a microwave-assisted extraction for the analysis of phenolic compounds from Rosmarinus officinalis

For potent biological activity natural phenols are considered as compounds with perspective of being isolated in their pure form from natural sources. For analytical purposes, as well as for potential industrial application, it is important to apply extraction procedure that allows efficient and time-consuming extraction of polyphenols. In this study a microwave-assisted extraction procedure has been optimized in respect to the recovery of rosemary polyphenols. The optimization was performed in respect to total polyphenols, flavonoids, total anthocyanins, monomeric and condensed anthocyanins. The efficiency of different solvents was investigated for different classes of polyphenols, as well as the influence of the magnetron power and the extraction time. The efficiency of the extraction using optimized extraction protocol for total phenolics was compared with that achieved by Soxhlet and ultrasound-assisted extraction. The present work proposes an optimal microwave-assisted extraction program for the determination of total polyphenolics, flavonoids, total anthocyanins, monomeric and condensed anthocyanins from rosemary.

Chemical Composition of Artemisia annua L. Leaves and Antioxidant Potential of Extracts as a Function of Extraction Solvents

This study was conducted to investigate the chemical and nutritional composition of Artemisia annua leaves in addition to determination of antioxidant potential of their extracts prepared in different solvents. Chemical composition was determined by quantifying fat, protein, carbohydrate, fiber, tocopherol, phytate, and tannin contents. Extraction of A. annua leaves, for antioxidant potential evaluation, was carried out using five solvents of different polarities, i.e., hexane, chloroform, ethyl acetate, methanol and water. Antioxidant potential was evaluated by estimating total phenolic (TPC), flavonoid (TFC) contents, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), DPPH radical scavenging activity and lipid peroxidation. Efficiency of different solvents was compared for the yield of antioxidant extracts from leaf samples and a clear variation was observed. The highest TPC, TFC, TEAC, DPPH radical scavenging and lowest lipid peroxidation were observed in MeOH extracts, whereas aqueous extract exhibited high ferric reducing antioxidant power; suggesting MeOH to be the most favorable extractant.