Method For Extraction Of Phenolic Compounds Research Articles

Alternative Assisted Extraction Methods of Phenolic Compounds Using NaDESs.

A renewed understanding of eco-friendly principles is moving the industrial sector toward a shift in the utilization of less harmful solvents as a main strategy to improve manufacturing. Green analytical chemistry (GAC) has definitely paved the way for this transition by presenting green solvents to a larger audience. Among the most promising, surely DESs (deep eutectic solvents), NaDESs (natural deep eutectic solvents), HDESs (hydrophobic deep eutectic solvents), and HNaDESs (hydrophobic natural deep eutectic solvents), with their unique features, manifest a wide-range of applications, including their use as a means for the extraction of small bioactive compounds. In examining recent advancements, in this review, we want to focus our attention on some of the most interesting and novel 'solvent-free' extraction techniques, such as microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) in relation to the possibility of better exploiting DESs and NaDESs as plausible extracting solvents of the phenolic compounds (PCs) present in different matrices from olive oil components, such as virgin olive pomace, olive leaves and twigs, virgin and extra virgin olive oil (VOO and EVOO, respectively), and olive cake and olive mill wastewaters (OMWW). Therefore, the status of DESs and NaDESs is shown in terms of their nature, efficacy and selectivity in the extraction of bioactive phytochemicals such as secoiridoids, lignans, phenolic acids and alcohols. Related studies on experimental design and processes' optimization of the most promising DESs/NaDESs are also reviewed. In this framework, an extensive list of relevant works found in the literature is described to consider DESs/NaDESs as a suitable alternative to petrochemicals in cosmetics, pharmaceutical, or food applications.

Exploring efficient extraction methods: Bioactive compounds and antioxidant properties from New Zealand damson plums

The study determined the best extraction method for phenolic compounds (rutin, catechin, epicatechin, naringenin, neochlorogenic acid, and rosmarinic acid) in the New Zealand damson plums. Accelerated solvent extraction (ASE) using ethanol and water was used to evaluate the solvent efficacy. Further comparisons were made among ASE, ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and a combined method (E + UAE) using water as the solvent. The findings showed that ASE for 40 min was the most effective method for extracting phenolic compounds (1.76 mg gallic acid equivalent/g) compared to other methods (UAE = 1.17, EAE = 1.3, and E + UAE = 1.45 mg/g). The ASE method also resulted in an extract with a higher antioxidant activity than other methods. The extraction time over 40 min decreased the yield regardless of the solvent used. Therefore, the ASE extraction method for 40 min is recommended as the best method for extraction of phenolic compounds from the New Zealand damson plums.

Phenolic compounds extraction by assistive technologies and natural deep eutectic solvents

Abstract Phenolic compounds are known to have a significant effect on human defense system due to their anti-inflammatory efficacy. This can slow down the aging process and strengthen the human immune system. With the growing interest in green chemistry concept, extraction of phenolic compounds from plants has been geared towards a sustainable path with the use of green and environmentally friendly solvents such as natural deep eutectic solvents (NADES). This review discusses both the conventional extraction and the advanced extraction methods of phenolic compounds using NADES with focus on microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) techniques ensued by a rationale comparison between them. Employing choline chloride-based natural deep eutectic solvents (NADES) is highlighted as one of the promising strategies in green solvent extraction of phenolic compounds in terms of their biodegradability and extraction mechanism. The review also discusses assistive extraction technologies using NADES for a better understanding of their relationship with extraction efficiency. In addition, the review includes an overview of the challenges of recovering phenolic compounds from NADES after extraction, the potential harmful effects of NADES as well as their future perspective.

Contribution of the Solvent Extraction Method for Phenolic Compounds, Flavonoids, and Fucoxanthin to the Antioxidative Properties in Extracts of Chaetoceros tenuissimus Meunier

Chaetoceros sp. has been found to possess significant amounts of valuable fucoxanthin, phenolics, and flavonoids, with enormous nutraceutical and antioxidant potential. The aim of this study was to employ ultrasound-assisted extraction to determine the antioxidant properties of extracts prepared from Chaetoceros tenuissimus using different solvents: Propylene glycol (PG), acetone (AC), and methanol (ME), with difference ultrasonication times (15 and 30 min). The total phenolic (TPC), flavonoid (TFC), and fucoxanthin (FUC) contents were evaluated. Antioxidant capacity was evaluated by DPPH and ABTS radical-scavenging assays and lipid peroxidation by TBARS. The FUC content was analyzed by HPLC-DAD. 30-min PG extract (PG-30) exhibited the highest TPC (2.75 ± 0.14 mg GAE.g−1 DW), and FUC (8.76 ± 0.06 mg FUC. g−1). Concerning total antioxidant capacity, PG-30 was the most effective against DPPH• (IC50 = 970.19 ± 7.70 µg. mL−1) and TBARS (IC50 = 717.05 ± 1.45 µg. mL−1), while 15-min PG extract (PG-15) presented the highest inhibitory activity against ABTS+• (IC50 = 150.02 ± 6.95 µg. mL−1). The study findings demonstrate that PG extracts of C. tenuissimus exhibit high potential antioxidant activity, likely associated with their content of FUC and phenolics, and could be used in cosmetic preparations and as phytonutrients. HIGHLIGHTS Chaetoceros tenuissimus Meunier from Chonburi province, Thailand High antioxidant activities of tenuissimus extracts by ultrasound assisted extraction with different solvents The correlation between chemical substances content and antioxidant activity GRAPHICAL ABSTRACT

Maceration and liquid-liquid extractions of phenolic compounds and antioxidants from Algerian olive oil mill wastewater.

Olive oil mill wastewater (OMW) is a major waste stream generated in olive oil industry. It is highly polluted due to phenolic compounds. The present study focused on the physicochemical properties of OMW as well as the quantitative and qualitative effects of two extraction methods of phenolic compounds which were liquid-liquid and maceration methods. Spectrophotometry and high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) were adopted to quantify the phytochemical contents and the phenolic compounds. The extract obtained by the maceration method showed the highest yields of total polyphenol, flavonoid, and tannin contents. The LC-MS results revealed the presence of 16 phenolic compounds in the macerated, and only 12 phenolic compounds were found in the extract of the second method. Quinic acid was identified as the most abundant compound. Moreover, the macerated extracts possessed the highest antioxidant potential as evidenced by their strong ferric reducing antioxidant power (FRAP) and their 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging activities. The phytochemical contents, as well as the antioxidant potentials of OMW after extraction using maceration, were significantly greater than using liquid-liquid method. Therefore, maceration seemed to be the most effective method for extracting phenolic compounds from OMW. The OMW constitute a rich source of natural phenolic compounds that could be used as a potential source of natural antioxidants.

Development and Box-Behnken design optimization of a green extraction method natural deep eutectic solvent-based for phenolic compounds from barley malt rootlets.

In recent years, attention has been turned finding new sources of phenolic compounds, antioxidant molecules, main by-products from the agri-food chain like barley malt rootlets (BMRs). Traditionally, phenolic compounds are extracted from food matrices using different procedures, for example, solid-liquid, liquid-liquid, or solid-phase extraction techniques employing organic solvents. With the advent of green chemistry, attention has been paid to the search for green, nontoxic, inexpensive, and nonflammable solvents and the natural deep eutectic solvents (NADESs) respect these characteristics. The aim of this project was to develop and optimize an environmentally friendly, inexpensive, and rapid extraction method for phenolic compounds from BMRs using natural DESs as extractive solvents. Several natural DESs were tested as extractive solvents and, among them, the best results in terms of total phenolic content were obtained using a choline chloride-malic acid (1:2 molar ratio)-based mixture. Box-Behnken experimental design guaranteed the extraction of 9.51 ± 0.83 gallic acid equivalent/g of BMRs, under the following optimal extraction conditions: 1:21 solid-to-liquid ratio, 80°C as extraction temperature, 43min as the time of extraction, and 29% as a percentage of added water in the NADESs. Phenolic acids and flavonoids were detected in the BMRs extract through HPLC-PDA/MS analysis.

Exploring the Extraction Methods of Phenolic Compounds in Daylily (Hemerocallis citrina Baroni) and Its Antioxidant Activity.

Daylily is a valuable plant resource with various health benefits. Its main bioactive components are phenolic compounds. In this work, four extraction methods, ultrasonic-assisted water extraction (UW), ultrasonic-assisted ethanol extraction (UE), enzymatic-assisted water extraction (EW), and enzymatic-assisted ethanol extraction (EE), were applied to extract phenolic compounds from daylily. Among the four extracts, the UE extract exhibited the highest total phenolic content (130.05 mg/100 g DW) and the best antioxidant activity. For the UE extract, the DPPH value was 7.75 mg Trolox/g DW, the FRAP value was 14.54 mg Trolox/g DW, and the ABTS value was 15.37 mg Trolox/g DW. A total of 26 phenolic compounds were identified from the four extracts, and the UE extract exhibited a higher abundance range of phenolic compounds than the other three extracts. After multivariate statistical analysis, six differential compounds were selected and quantified, and the UE extract exhibited the highest contents of all six differential compounds. The results provided theoretical support for the extraction of phenolic compounds from daylily and the application of daylily as a functional food.

OPTIMIZATION OF EXTRACTION OF POLYPHENOLS FROM CHESTNUT WASTE PRETREATED BY OHMIC HEATING USING BOX-BEHNKEN DESIGN

Chestnut processing produces a large amount of waste peels, which contain considerable polyphenols. The aim of this research was to optimize the extraction method for phenolic compounds from industrial chestnut peel pretreated by ohmic heating (OH) by using response surface methodology (RSM). Box-Behnken design (BBD) was used to investigate the effects of three independent variables; namely, extraction time, solid to solvent (S/S) ratio, and temperature, on total phenolic content (TPC) and antioxidant capacity (AC). All independent variables influenced the TPC and AC of the peel extracts. The optimum extraction conditions found were 22.02 min, 1/39.70 (w/v), and 60 °C for extraction time, S/S ratio, and extraction temperature, respectively, resulting in the highest TPC of 34.83 mg GAE/g dry matter (DM) and AC of 35621.38 mmol ascorbic acid equivalent (AEAC)/100 g DM by DPPH. This study showed that water was highly successful for the extraction of polyphenols from the pretreated chestnut peel.

Optimization of the Ultrahigh-Pressure–Assisted Extraction of Phenolic Compounds and Antioxidant Activity from Palm Dates (Phoenix dactylifera L.)

The goal of this study was to optimize an innovative ultrahigh-pressure–assisted extraction method for phenolic compounds of date palm (Phoenix dactylifera L.) using response surface methodology (RSM). A four-factor-three-level Box–Behnken design (BBD) was used to test the following extraction parameters: ethanol concentration (X1), solvent to sample ratio (X2), temperature (X3), and pressure (X4). Analysis of variance (ANOVA) results revealed that the main treatment X1, X2, and X4 significantly affected extraction yield, while X3 did not. The optimum response for the combination of phenolic compounds and antioxidant activity was obtained with following extraction parameters predicted by the model: X1 = 60.54% (v/v), X2 = 70 mL/g, X3 = 65 °C, and X4 = 600 MPa. These parameters were validated in an additional experiment carried out under the optimal conditions given by experimental results; the experimental values obtained were in close agreement with the predicted values. This suggests that the RSM BBD model described in this work is an efficient quantitative tool to predict the extraction efficiency of polyphenols and antioxidants capacity from date palm fruit.

Establishment of ultrasound-assisted extraction of phenolic compounds from industrial potato by-products using response surface methodology

Potato processing generates large amounts of by-products, which include potato peels and the outer layers of flesh, which contain phenolic compounds. The purpose of this study was to establish an extraction method for phenolic compounds from industrial potato by-products by using response surface methodology (RSM). Box-Behnken design (BBD) was performed to optimize the extraction conditions of phenolic compounds considering different extraction temperature, ratios of ethanol/water, time of extraction and sample/solvent ratio. The optimum extraction conditions were obtained with ethanol/water 55/45 (v/v) by ultrasound bath during 35 min at 35 °C and 1/10 sample/solvent ratio. The best conditions were applied to determine the phenolic content in five potato by-products. The analyses by HPLC-DAD-ESI-MS showed that chlorogenic acid accounted for a 49.3–61% of the total phenolic compounds.Positive Pearson correlations between HPLC data and antioxidant activity confirmed that the phenolic compounds had significant antioxidant properties.

Analysis of phenolics in the peel and pulp of wild apples (Malus sylvestris (L.) Mill.)

A simple and efficient ultrasound extraction method for phenolic compounds in the pulp and peel of Malus sylvestris (wild apples) was developed using multivariate methodology. Optimal extraction conditions were obtained using this methodology for peel and pulp samples (2.0 g), including solvent volume 100 mL and 79 mL, methanol concentration 100% (v/v) and 20% (v/v), extraction time 33 min and 40 min, extraction temperature 65 °C and 80 °C, respectively. The peel and pulp extracts were analysed by HPLC-PDA using a C18 Phenomenex Kinetex column. Among the phenolic compounds present in our samples, we quantified (mg/g fresh weight) chlorogenic acid, 0.791; epicatechin, 1.18; and phloridzin, 0.106 in the pulp extract, whereas the peel extract contained chlorogenic acid, 0.568; epicatechin, 1.36; phloridzin, 0.207; catechin, 0.187; hyperoside, 0.261; and quercitrin, 0.256 mg/g. The antioxidant activity of the extracts was measured by spectrophotometric methods Peel extract proved to be a better antioxidant than pulp extract. Additionally, the stability of the analysed phenolic compounds was tested by in vitro digestion procedures. Simulated in vitro digestion showed that the concentrations of all analysed phenolic compounds (except chlorogenic acid) decreased during the intestinal phase of digestion.

High-throughput extraction method for phenolic compounds in olive fruit (Olea europaea)

Phenolic compounds in olive fruit significantly influence the health benefits and sensory properties of processed olive oil and table olives. A simple and rapid extraction method using homogenization with dimethyl sulfoxide (DMSO) and solid-phase extraction (SPE) cleanup was developed and optimized for ten phenolics in olive fruit. Quantification was performed using high-performance liquid chromatography with diode-array detection (HPLC-DAD). Chromatographic separation of the relevant compounds was achieved using a C18 column (5 μm, 4.6 × 250 mm). The method was validated for accuracy and precision using replicate fortifications (n = 5) in 3 olive matrices (fresh, brined and California-style olives). All compounds were recovered between 80 and 120% and had relative standard deviations below 12.5%. Limits of detection (LOD) and limits of quantification (LOQ) ranged from 0.06 to 7.4 mg/kg and 0.20 to 23.3 mg/kg, respectively. The method was used to quantify phenolic concentrations in fresh olives at different maturities, brined olives and California-style olives, including the analysis of green ripe olives and black ripe olives processed without ferrous gluconate for the first time.

MAE of phenolic compounds from blueberry leaves and comparison with other extraction methods

Blueberry leaves are a prospective source of phenolic compounds which can be obtained by microwave assisted extraction leading to higher yield in shorter period of time and with lower solvent consumption when compared to solvent extraction. During this study, three experiments with microwave assisted extraction, were separately designed and conducted using highbush blueberry (variety Bluetta) leaves collected during the late fall season. The yields of different compounds obtained during these experiments with microwave extraction were compared with ultrasonic extraction for one hour and 24-h room temperature extraction. The first microwave assisted extraction experiment was conducted to streamline the combination of ethanol and citric acid concentration for further analysis of microwave as a potential extraction method for phenolic compounds and anthocyanins from blueberry leaves. During the second experiment the effect of microwave power level (10–20% absolute power level) and time of extraction (4–16min) on total phenolics, total anthocyanins and chlorogenic acid was studied which was further used to design the third experiment consisting of a face-centred central composite design with varying factors namely power level and time, each at 3 levels. All the experimental combinations for the 2nd and 3rd experiments were conducted with 80ml of solvent consisting of 30% ethanol and 1.5M citric acid combination in ratio of 97:3 (v/v). The total anthocyanins and chlorogenic acid extracted during the study were between 2.321–2.636mg malvidin 3-glucoside/g dry matter and 49.34–52.66mg chlorogenic acid/g dry matter respectively, not showing a huge variation between highest and lowest yields, however both compounds with a noteworthy yield. For total phenolics extraction, both microwave power and time of microwave application were observed to be statistically significant factors and the yield of total phenolics was found to be much higher (in the range of 92.719–128.76mg GAE/g dry weight) than for 24-h extraction at room temperature (average 89.164mg GAE/g dry weight) and 1h extraction by sonication (average 97.77mg GAE/g dry weight) with the same solvent combination.

Effects of extraction methods of phenolic compounds from Xanthium strumarium L. and their antioxidant activity

The effect of extraction methods and solvents on overall yield, total phenolic content, antioxidant activity, and the composition of the phenolic compounds in Xanthium strumarium extracts were studied. The antioxidant activity was determined by using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), and the composition of the phenolic compounds was determined by HPLC-DAD and LC/MS. All results were affected by the extraction method, especially by the solvent used, and the best results were obtained with the methanol extract. The methanolic and ethanolic extracts exhibited strong antioxidant activity, and the chlorogenic and ferulic acids were the most abundant phenolic compounds in the extracts.

Comparison of Ultrasonic Extraction with Conventional Extraction Methods of Phenolic Compounds in Longan (Euphoria longana Lamk.) Seed

Three different extraction methods – hot water (HWE), ethanol (EE) and ultrasonic-assisted water extraction (UAE) – were evaluated for extraction of phenolic compounds in longan (cultivar Edor) seed. The findings indicated that longan seed extracts contained three major phenolic compounds, analyzed by HPLC, including gallic acid, corilagin and ellagic acid. The content of total polyphenolic compounds and antioxidant activities was determined using the Folin-Ciocalteu method and the DPPH assay, respectively. Longan seed extraction by HWE contained the highest yield, total polyphenol content and antioxidant activities (42.80%, 41.250mg gallic acid/g and IC50 = 0.017 mg/ ml, respectively). UAE produced a higher yield than EE, but lower than HWE, with the lowest extraction time. Moreover, gallic acid content (16.55 mg/g) and corilagin content (35.62 mg/g) extracted by UAE were higher than those of HWE and EE. Ellagic acid content obtained from UAE was significantly (P<0.05) higher than that from EE, but not significantly different from that of HWE. The application of UAE could provide an alternative method for extraction of photochemical from longan seeds.

小豆子実フェノール成分のメタノールによる抽出条件の検討及び種皮部と子葉部の含量差異について : 小豆生産地の土壌の種類が子実成分組成と調理特性に及ぼす影響(第3報)

小豆子実フェノール成分のメタノールによる抽出条件の検討及び種皮部と子葉部の含量差異について : 小豆生産地の土壌の種類が子実成分組成と調理特性に及ぼす影響(第3報)

Determination of phenolic compounds in Prunella L. by liquid chromatography-diode array detection

Four species of Prunella L. ( Prunella vulgaris L., Prunella laciniata L., Prunella grandiflora L. and Prunella orientalis Bornm.) belong to the family of Lamiaceae and representing popular Western and Chinese herbal medicine were examined for the content of phenolic compounds. Phenolic acids (rosmarinic acid, caffeic acid, ferulic acid, chlorogenic acid, protocatechuic acid), flavonoids (rutin, quercetin) in different quantitative proportions depending on extracts were determined by the rapid, selective and accurate method combining solvent/acid hydrolysis extraction and high performance liquid chromatography-diode array detection (HPLC-DAD). Water, methanol, butanol, acetonitrile, ethyl acetate, hexane and their acidic solutions were used to examine the efficiency of different solvent systems for the extraction of phenolic compounds. Acid hydrolysis extraction was established as the most suitable extraction method for phenolic compounds.

Microwave-assisted extraction of phenolic compounds from wine lees and spray-drying of the extract

Most research on extraction of phenol compounds from wine by-products and commercial exploitation of extracts use grape seeds and/or skins as raw materials. Looking for alternative antioxidants sources, obtaining antioxidant extracts from wine lees (also known as dregs), a sub-exploited by-product of winemaking process, is here presented. Microwave-assisted extraction (MAE) of phenolic compounds from wine lees has been optimized using the total phenols index, the ORAC values and yield of the extraction as response variables. Under the optimal working conditions, the proposed MAE method provides better extraction efficiency in a much shorter time (17 min) than the conventional extraction method for phenolic compounds (24 h). The liquid extract obtained by MAE was spray-dried. The type and amount of excipients used, as well as the spray-drying temperature, were optimized in order to minimize the oxidation of phenolic compounds and maximize the yield of the spray-drying process. The total phenols index in the dried extract thus obtained was 36.8% (expressed as gallic acid), showing an ORAC value of 3930 μmol TE/g. Additionally, Mv3G, Cm-Mv3G, myricetin, quercetin, quercetin-3-β-glucoside, caffeic acid and p-coumaric acid were quantified in the dry extract by HPLC–DAD. The results indicate that wine lees antioxidant extracts can be a suitable and cheap alternative to those obtained from grape seeds or skins.

Extraction, distribution and characterisation of phenolic compounds and oil in grapeseeds

Five factors, extraction means, extraction repeats, extraction solvents, sample granularities, and grinding manners, were investigated and compared to optimise the extraction methods of phenolic compounds from grapeseed. Twenty minutes sequential sonication for three repeats was a preferred extraction means for assessment of phenolic content in grapeseed over three repeats 100-min sequential mechanical agitation. Methanol/water/HCl (70:29:1, v/v/v) was the best among the solvent compositions tested. Grinding granularity showed a significant ( p = 0.05) effect on the yield of phenolic compounds when the sample was ground with a grinder and separated to different granularities by sieves. Grinding sample with mortar in liquid nitrogen could provide samples with uniform size and thus give a more consistent evaluation of phenolic compounds in grapeseed. Significant correlation coefficients ( p < 0.01) among total phenols, total flavan-3-ols, and total proanthocyanidins contents in grapeseed extracts were observed. In addition, phenolic compounds and oil were very unevenly distributed in grapeseed as about 90% of phenolic compounds were observed in seed coat while about 60% of oil was in the endosperm and embryo.