Total Phenolic Content Of Extracts Research Articles

Maceration of Waste Cork in Binary Hydrophilic Solvents for the Production of Functional Extracts

Waste-grade cork samples of Quercus cerris were subjected to maceration extraction using 7 different solvents, including pure water (I), pure acetone (II), 75% aqueous ethanol (III), 75% aqueous methanol (IV), 75% aqueous acetone (V), 50% aqueous acetone (VI), and 25% aqueous acetone (VII). The extract yields, extract compositions, as well as antioxidant and antimicrobial activities of the extracts were analyzed. The results showed that maceration extraction was highly efficient, particularly with binary solvents resulting in up to 6% extract yield and up to 488 mg GAE/g extract total phenolic content. The extracts exhibited a variable antioxidant activity determined by DPPH and FRAP methods as well as antimicrobial activity against gram-positive bacteria and fungus determined by agar diffusion test. The CIELAB color parameters of extracts were correlated with maceration time, and the correlation was highest with pure water extracts. The FT-IR spectra of acetone-extracted cork revealed six key markers of phenolic compounds with the presence of peaks at approximately 2920 cm−1, 2850 cm−1, 1609 cm−1, 1517 cm−1, 1277 cm−1, and 1114 cm−1. The overall results suggest that the maceration of waste cork in binary solvents and pure acetone are green alternatives to conventional Soxhlet extraction for the production of polar extracts.

Chromatography-mass spectrometry based chemical profiling of Mucuna pruriens (L.) DC. and its beneficial effect against hydrogen peroxide-induced oxidative stress in HEK 293T cells and breast cancer cells

Chemical profiling of Mucuna pruriens (L.) DC. and exploring its efficacy against H2O2-induced oxidative stress in HEK 293T cells and anticancer potential was the aim of this pilot study. One of the main areas of natural product research in the modern period is the search of naturally occurring antioxidants and their potential to ward-off cancer. So, medicinally and pharmacologically important plant M. pruriens was selected for the study. The collected M. pruriens seeds were sequentially extracted with hexane, chloroform, methanol, water and chemoprofiled using GC-MS, GC-FID and LC-QTOF-MS/MS. DPPH, phosphomolybdenum, FRP and ferrous chelating assays were performed for in vitro antioxidant efficacies whereas Folin-Ciocalteu method for total phenolic content of sequential extracts. The cellular antioxidant efficacy of the screened extract was studied through H2O2-induced oxidative stress in HEK 293T cells (MTT and PI Live dead assay with FACS). The anticancer effect of sequential extracts was checked on MCF-7 cells using MTT assay. The chemical profiling revealed the presence of high-value phytochemicals like terpenes, alkaloids and phenolic compounds in these extracts. Water extract was profound for in vitro antioxidant activity and comparable with the synthetic antioxidant. The total phenolic content of the extracts and its positive correlation with antioxidant activity were also established. The screened water extract further showed a promising protective effect on the oxidative stress induced HEK 293T cells and also effective for its cytotoxicity on MCF-7 cells. Many of the identified metabolites are reported for the first time from the selected plant. The potential of water extract to serve as a cheap and alternative antioxidant instead of synthetic options was explored. The high in vitro cytotoxicity of water extract against breast cancer cells indicates the chance of exploration of these extracts/its high-value phytochemicals as an anticancer drug. Since the water extract is screened with remarkable activities, this study has further relevance as both economic and environmental friendly. As it is water and devoid of any solvent residues, the screened extract would not impart any environmental pollution and health hazards.

Ultrasound-assisted ethanolic extraction of punicalagin from pomegranate by-products influenced by cultivar, pre-drying treatment, particle size, and temperature

The novelty of this research is to describe the effect of different ultrasound-assisted extraction operating conditions on the punicalagin (∑Pn) and total phenolic content (TPC) yield of pomegranate peel of two cultivars: Wonderful (W) and Mollar de Elche (ME). Besides cultivar, drying method (convective and freeze drying), particle size (<56 and 56–101 μm), extraction temperature (25 and 45 °C) and time (0–60 min) were categorical variables included in the experimental design to optimize the process using a polynomial regression model. Both ∑Pn and TPC extraction was higher in freeze-dried than in convectively dried samples. Although the interaction of the above-mentioned variables must be considered, the type of drying influenced the extraction of ∑Pn between cultivars, being higher in ME than W when the material was freeze-dried. For the smallest particle size and higher temperature (45 °C), the extracted ∑Pn and TPC was higher than samples with higher particle size and lower extraction temperature (25 °C).

ENHANCED TOTAL PHENOLIC CONTENT EXTRACTION FROM CUCUMIS MELO L. (KULTIK) KERNEL BY DEEP EUTECTIC SOLVENT (DES)

Kernel of Cucumis melo L is a by-product produced from the water-melon production process. The phenolic compounds could be considered as a potential bioactive source for industrial applications. Therefore, the extraction of these compounds as much as possible will decrease valuable waste and could lead to produce value-added products. In the first part of this study, comparation of the effect of DESs and conventional solvent on total phenolic content (TPC) was performed. Some DESs had significantly better extraction yield than conventional solvent. Therefore, optimization of extraction conditions was performed by single factor experiment.&#x0D; Optimized parameters are molar ratio, type of HBA (hydrogen bond acceptor), addition of water content, extraction time and extraction temperature. From the results obtained, all these parameters were found to have an impact on TPC extraction yield. Also, it is noteworthy that the extraction yield using some selected parameters was on decrease after a certain extent. The best extraction parameter for Cucumis melo L. was found to be choline chloride as HBA, 1:4 molar ratio, %30 water addition, 500 extraction temperature and 30 min extraction time. This result confirms that kernel of Cucumis melo L. is a valuable ingredient due to its bioactive content, DESs could be a good alternative to conventional solvents and the industrial applications of DESs could be possible.

Microwave-assisted extraction of bioactive compounds from Sarawak Liberica sp. coffee pulp: Statistical optimization and comparison with conventional methods.

Coffea liberica, commonly known as Liberica coffee, is a kind of coffee that originated in Liberia, a West African country. It is considered a less-known coffee bean variety, which accounts for less than 2% of commercially produced coffee worldwide. In this study, the influences of optimization of microwave-assisted extraction (MAE) on the total phenolic content (TPC), total flavonoid content (TFC), and total carbohydrate content (TCC) of bioactive compounds extracted from Sarawak Liberica sp. coffee pulp were studied. Response surface methodology was adopted with a face-centered central composite design to generate 34 responses by taking three microwave parameters into consideration, microwave power (watt), time of irradiation (second), and solvent-to-feed ratio as independent variables. As a result, the findings revealed that optimum extraction conditions were conducted as follows: microwave power of 700 W, time of irradiation of 180 s, and solvent-to-feed ratio of 86.644:1. While under optimal extraction conditions, MAE outperformed conventional maceration extraction in terms of extraction efficiency and had no significant difference (p < .05) with Soxhlet extraction on the extraction of TPC (12.94 ± 2.25 mg GAE/g), TFC (9.84 ± 0.38 mg QE/g), and TCC (876.50 ± 64.15 mg GE/g). Present work advances the usage of Sarawak Liberica sp. coffee for the development of functional products and aids in reducing environmental pollution by utilization of coffee pulp waste.

Gleichenia linearis (Burm.) C. B. Clarke Leaves Extract Potent as a Medicinal Plant Based on Its Phytochemical Profile and The Total Phenolic Content

Resam fern (Gleichenia linearis (Burm.) C.B. Clarke) is a terrestrial plant that is easy to grow and has been used for medicinal purposes as by the community empirically. This study aimed to explore the potential of Gleichenia linearis (Burm.) C.B. Clarke) as medicinal plants based on their phytochemical profiles and total phenol content of the extract. Gleichenia linearis (Burm.) C.B. Clarke leaves were extracted with aquadest and methanol as a solvent by maceration method. Phytochemical content was detected qualitatively and the total phenol content was determined using colorimetric method with Folin-Ciocalteu reagent. As the result, qualitative screening for secondary metabolic contents in Gleichenia linearis (Burm.) C.B. Clarke extract found that the aqueous extract contains alkaloids, phenols, flavonoids, tannins, triterpenoids and steroids, but the saponin and steroid were not detected. In the methanol extract, all secondary metabolites were detected except triterpenoids. The total phenol content of methanol extract was higher than that of aqueous extract with levels of 127,08 mg/g GAE and 42,32 mg/g GAE, respectively. Based on these findings, it can be concluded that the Gleichenia linearis (Burm.) C.B. Clarke leaf has the potential to be developed as a medicinal plant.

Antioxidant and Antitumorigenic Activities of the Standardized Water Extract From Fruit of Terminalia chebula Retz. var. chebula

Background Terminalia chebula Retz. var. chebula ( T chebula) has been traditionally used as a crude drug for treating various diseases, including skin disorders. This study aimed to investigate the potential antioxidant effects and antitumorigenic activity of an aqueous extract from the fruit of T chebula. Methods The extract's total phenolic content and antioxidant activity were measured using Folin-Ciocalteu, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) tests, respectively. The 2 ´,7 ´-dichlorodihydrofluorescin diacetate assay was employed to evaluate the extract's ability to reduce intracellular reactive oxygen species (ROS) in U-937 human monocytic cell lines which had been treated with hydrogen peroxide for 30 min. Male ICR mice ( n = 30, 5 groups) were used to investigate the influence of T chebula extract on dimethylbenz[a]anthracene (DMBA)/12- O-tetradecanoylphorbol 13-acetate (TPA)-induced carcinogenesis. After 20 weeks of treatment with T chebula extract, tumor incidence, size, and number were assessed. The major phenolic compounds in the extract were determined using high-performance liquid chromatography. Statistical analysis was performed using ANOVA followed by post hoc least significant difference test. Results T chebula extract effectively reduced intracellular ROS and scavenged antioxidants in vitro. The IC50 values of the extract as measured by DPPH and FRAP assays were 109.0 ± 14.5 μg/mL and 2.39 ± 0.17 μg/mL, respectively. Moreover, 4 mg of T chebula extract significantly decreased the incidence, volume, and number of tumors in DMBA/TPA-induced skin tumorigenesis in mice. Conclusion T chebula extract effectively reduced intracellular ROS, and significantly decreased the incidence, volume, and number of tumors in DMBA/TPA-induced skin tumorigenesis in mice. These findings suggest that T chebula extract could be a promising therapeutic agent for skin tumors and other oxidative stress-related diseases.

Antioxidant Activity of Extracts from Bidens pilosa-A Medicinal Plant from the Kingdom of Lesotho

Bidens pilosa finds therapeutic applications in the traditional medicine. In the present study, we aimed to evaluate the antioxidant activity of various extracts obtained from the leaves and stem-bark of B. pilosa by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing power assay. We also aimed to determine the total phenolic contents (TPCs) by Folin-Ciocalteu colorimetric method and total flavonoid contents (TFCs) by the aluminium chloride colorimetric method. Various solvent extracts were obtained from the leaves and stem-bark of B. pilosa by maceration and hot solvent extraction techniques. The extracts from leaves and stem-bark exhibited radical scavenging activity in the ranges of 4.40 ± 1.02-81.18 ± 1.14% and 5.92 ± 2.16-79.34 ± 8.43%, respectively at concentrations of 200-3,000 µg/mL. The positive control, ascorbic acid exhibited radical scavenging activity in a range of 55.17 ±1.89-88.12 ± 1.31% at the same concentrations. Additionally, the methanol extracts from both leaves and stem-bark were found to be the most potent with IC50 values of 848.54 and &lt; 200 µg/mL, respectively. The positive control, ascorbic acid exhibited an IC50 value &lt; 200 µg/mL. Furthermore, the extracts from the leaves and stem-bark exhibited ferric reducing power in the ranges of 0.095 ± 0.017-1.175 ± 0.084 and 0.093 ± 0.006-1.100 ± 0.065, respectively at concentrations of 5-100 µg/mL. The positive control, ascorbic acid exhibited a ferric reducing power in the range of 0.326 ± 0.00-1.213 ± 0.078 at concentrations of 5-100 µg/mL. In addition, the TPCs of extracts from the leaves and stem-bark were determined to be in the ranges of 9.03 ± 2.34-179.31 ± 0.96 and 10.93 ± 1.04-154.04 ± 2.15 mg GAE/g of DW of extract, respectively. Similarly, the TFCs of extracts from the leaves and stem-bark were determined to be in the ranges 1.28 ± 0.05-29.33 ± 4.19 and 1.89 ± 0.58-27.75 ± 2.67 mg QE/g of DW of extract, respectively. From this study, we concluded that various extracts obtained from B. pilosa showed a moderate to strong radical scavenging and ferric reducing power and possessed a significant amount of TPCs and TFCs.

Bioactive components, sun protective properties, and total phenolic contents of halobacterial extracts

Halophilic bacteria are microorganism groups with key industrial potential due to their primary and secondary metabolites. In this study, three halophilic bacteria were identified biochemically and phylogenetically, and visualized with advanced imaging systems such as scanning electron and atomic force microscopes. The data obtained identified the following species strains, Salinicoccus roseus strain EMK96, Salinicoccus amylolyticus strain RB5, and Salicola marasensis strain OSK. The industrial potential of halophilic bacteria were identified by investigating the catalase, oxidase, gelatinase, amylase, caseinase, and esterase enzyme activities, and pigments. The sun protection factors, total polyphenol content, and bioactive volatile components were also identified. SPF values and total phenolic content of the extracts obtained from different strains showed significant differences (P < 0.05). The highest SPF and total phenolic content were detected in the second extract of S. roseus (P < 0.05). In addition, bacterioruberin, commonly known as archaeal carotenoid, was also detected in the bacterial strain S. roseus. As a result of qualitative volatile component analysis of bacterial extracts, a total of 108 components were identified from different extracts. This is the first study to determine the sun protection factor, total polyphenol content, and volatile chemical components of these three halophilic bacterial extracts.

Effect of Hydrogen-Enriched Solvents on the Extraction of Phytochemicals in Propolis.

Propolis, one of the most important bee products, cannot be used in its raw form. The efficiency of the bioactive components of propolis increases with the extraction process. The choice of solvent to be used in the extraction of propolis is effective in determining the properties of the extract. Ethanol is the most widely used solvent, which significantly increases the efficiency of its bioactive components in the extraction of propolis. Effective nonalcohol-based extraction techniques have become important since alcohol-based extracts cause some discomfort and cannot be used in people with alcohol intolerance. The use of water in propolis extraction is less preferred than ethanol because it does not thoroughly dissolve the bioactive components. In this study, the effect of incorporating hydrogen into solvents (water, ethanol, and methanol) on the extraction of total phenolic content, total flavonoid content, antioxidant activities, and phenolic compound profile of the propolis sample was evaluated. Incorporation of H2 into water, ethanol, and methanol led to an increase in total phenolic content by 19.08, 5.43, and 12.71% and in the total flavonoid content by 28.97, 17.13, and 2.06%, respectively. Besides, the highest increases in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging activities were observed in hydrogen-rich water (4.4%) and hydrogen-rich ethanol (32.4%) compared to their counterparts, respectively. On the other hand, incorporation of H2 into different solvents led to significant increases in different phenolics, and it was observed that the level of change was dependent on the type of the phenolic compound and the solvent used. This study is important in terms of using hydrogen-enriched solvents to extract phenolics from propolis for the first time. Using hydrogen-rich solvents, specifically hydrogen-rich water, was observed to be an effective method for the improvement of phytochemical extraction efficiency in propolis.

Concurrent Optimization of Ultrasonic-Assisted Extraction of Total Phenolic Compounds and In Vitro Anticancer and Antioxidant Potential of Pulicaria schimperi (Aerial Parts) Using Response Surface Methodology

This study aimed to maximize the dependent variables [total phenolic content (TPC), antioxidant (DPPH and ABTS), and anticancer activities (against HepG2 and MCF-7 cells)] from P. schimperi aerial parts by optimizing three independent variables (extraction temperature, extraction time, and liquid-to-solid ratio) of ultrasound-assisted extraction (UAE) using the Box–Behnken design (BBD) of response surface methodology (RSM). For each of the dependent variables, the projected quadratic models were found to be very significant (p &lt; 0.001). The extraction temperature and extraction time had a significant impact on the TPC extraction, antioxidant, and anticancer properties (p &lt; 0.05). The best conditions were identified as an extraction temperature of 54.4 °C, extraction time of 48 min, and liquid-to-solid ratios of 20.72 mL/g for the simultaneous extraction of the TPC, antioxidant, and anticancer properties of P. schimperi. The experimental results and the expected values agreed under these circumstances. Regarding the high extraction effectiveness and antioxidant and anticancer effects at comparably low extraction temperature and duration, UAE demonstrated considerable benefits over conventional solvent extraction (CSE). This improved UAE approach has shown a potential use for effective polyphenolic antioxidant extraction from P. schimperi aerial parts in the nutraceutical sectors.

Ultrasound-Assisted Extraction of Total Phenolic Compounds and Antioxidant Activity Evaluation from Oregano (Origanum vulgare ssp. hirtum) Using Response Surface Methodology and Identification of Specific Phenolic Compounds with HPLC-PDA and Q-TOF-MS/MS.

Oregano is native to the Mediterranean region and it has been reported to contain several phenolic compounds particularly flavonoids that have been related with multiple bioactivities towards certain diseases. Oregano is cultivated in the island of Lemnos where the climate promotes its growth and thus it could be further used in promoting local economy. The aim of the present study was to establish a methodology for the extraction of total phenolic content along with the antioxidant capacity of oregano by using response surface methodology. A Box-Behnken design was applied to optimize the extraction conditions with regard to the extraction time, temperature, and solvent mixture with the use of ultrasound-assisted extraction. For the optimized extracts, identification of the most abundant flavonoids (luteolin, kaempferol, and apigenin) was performed with an analytical HPLC-PDA and UPLC-Q-TOF MS methodology. The predicted optimal conditions of the statistical model were identified, and the predicted values confirmed. The linear factors evaluated, temperature, time, and ethanol concentration, all showed significant effect (p < 0.05), and the regression coefficient (R2) presented a good correlation between predicted and experimental data. Actual values under optimum conditions were 362.1 ± 1.8 and 108.6 ± 0.9 mg/g dry oregano with regard to total phenolic content and antioxidant activity based on 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. Additionally, further antioxidant activities by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) (115.2 ± 1.2 mg/g dry oregano), Ferric Reducing Antioxidant Power (FRAP) (13.7 ± 0.8 mg/g dry oregano), and Cupric Reducing Antioxidant Capacity (CUPRAC) (1.2 ± 0.2 mg/g dry oregano) assays were performed for the optimized extract. The extract acquired under the optimum conditions contain an adequate quantity of phenolic compounds that could be used in the production of functional foods by food enrichment procedure.

Optimization of accelerated solvent extraction of bioactive compounds from Eucalyptus intertexta using response surface methodology and evaluation of its phenolic composition and biological activities

Polyphenols-rich extracts were obtained by accelerated solvent extraction (ASE) from E. intertexta leaves and analyzed by HPLC for the first time. Response surface methodology (RSM) based on central composite experimental design (CCD) was used to investigate the effect of three independent variables (temperature, extraction time, and ethanol concentration) on extraction yield, phenolic content, antioxidant, and anti-xanthine oxidase activities. The statistical analysis indicated that experimental data were well fitted to a quadratic polynomial model with regression coefficient values of more than 0.96 for all studied responses. Optimized extraction conditions, obtained by the maximization of a global desirability function, were 26.6% ethanol concentration, dynamic time of 36 min and a temperature of 179 °C. Under these optimal conditions the experimental values of the studied responses were 52.3 g extract/100 g DW extraction yield, 180.7 mg GAE/g extract total phenolic content, 17.2% antioxidant activity, and 55.3% anti-xanthine oxidase capacity. The HPLC analysis of all CCD extracts allowed to quantify twenty-two phenolic compounds in which eight molecules have not been reported previously in the genus of Eucalyptus. 3,4-dihydroxybenzoic, methyl ester, gallic acids, myricitrin, catechin, epicatechin, and polydatin were the most abundant phenolic compounds. The percentages of these compounds in extracts depend on the operating conditions. The best recovery of flavonoids (583 mg/g) was obtained at 100 °C, 10 min, and 44% ethanol, whereas phenolic acids (357 mg/g) were favored at a lower ethanol concentration of 11% and higher temperature and exposure time (180 °C, 36 min). The extraction of stilbenes (148 mg/g) was at its maximum at 140 °C, 1 min, and 27.5%.

ВПЛИВ РОЗЧИННИКІВ ДЛЯ ЕКСТРАКЦІЇ НА ВМІСТ ФЕНОЛІВ ТА АНТИОКСИДАНТНУ ЗДАТНІСТЬ БІОМАСИ ШТАМІВ XYLARIA POLYMORPHA ТА XYLARIA LONGIPES

Background. Fungi of the genus Xylaria are known for their wide range of secondary metabolites, including antioxidant polyphenolic compounds. Due to their critical role as chain-breaking antioxidants, phenolic compounds have been studied extensively in plants and fungi. The objective of this study was to assess and compare the total phenolic content and antioxidant capacities of the biomass of different strains of two common representatives of this genus in Ukraine – Xylaria polymorpha and Xylaria longipes – by applying various solvents for extraction. Methods. A vegetative mycelium was cultivated in submerged conditions and extracted with ethanol, methanol, and ethyl acetate. Total phenolic content in extracts was determined using the Folin–Ciocalteu method with gallic acid as the standard. Antioxidant activity was assessed by determining the DPPH (2,2-Diphenyl-1-picrylhydrazyl) free radical scavenging spectrophotometric assay. The correlation between the total phenolic content and antioxidant capacity of the extracts was assessed using the Pearson correlation coefficient for each organic solvent. Results. Methanol was the most effective solvent in yielding the highest quantities of phenolic compounds. Among all the strains studied, X. polymorpha IBK 2736 exhibited the maximum yield of phenolic compounds at 21,64 ± 0,03 mg GAE/g. Conversely, when ethyl acetate was used as the solvent, the phenolic yield from the biomass of the same strain was significantly lower at 0,68 ± 0,14 mg GAE/g, as well as for other strains in our investigation. Furthermore, the methanol extract of X. longipes IBK 2726 demonstrated the highest antioxidant activity, reaching 88,99 ± 0,07 %, while the ethyl acetate extract of X. longipes IBK 2718 exhibited the lowest antioxidant activity with a value of 41,28 ± 0,33 %. Conclusіons. The results indicated that the amount of extracted phenolic compounds was greatly influenced by the choice of solvent. Methanol was found to be the most effective solvent for extracting these compounds from studied strains, outperforming ethanol and ethyl acetate. Moreover, methanol extracts displayed a strong antioxidant capacity, and the correlation analysis confirmed the relationship between it and the phenolic content present in them. Overall, all the strains investigated showed significant antioxidant potential, highlighting the importance of further studies of the chemical properties of their antioxidant components.

Essential oil and extracts from Lavandula angustifolia Mill. cultivated in Bosnia and Herzegovina: Antioxidant activity and acetylcholinesterase inhibition

Lavender (Lavandula angustifolia Mill.) is a perennial, aromatic, medicinal, and decorative plant widespread in the Mediterranean. Due to the high content of essential oil and numerous beneficial properties, it is an extremely valued plant species. In Bosnia and Herzegovina, lavender is cultivated mainly for the needs of the cosmetic and pharmaceutical industries. In this research, the antioxidant activity and acetylcholinesterase inhibition of essential oil (EO) and extracts isolated from lavender were evaluated. L. angustifolia EO was isolated using whole plant material in the flowering period by steam distillation and analyzed by gas chromatography (GC) with flame-ionization (FID) and mass spectrometric (MS) detection. Extracts were prepared by ultrasonic extraction in solvents of different polarities. Total phenolic content in extracts was determined using Folin–Ciocalteu reagent. The antioxidant activity of EO and extracts was examined by two methods, 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging activities and ferric reducing/antioxidant power (FRAP), while the acetylcholinesterase (AChE) inhibitory potential was determined using modified Ellman’s method. The EO was high in content of linalool (27.72%) and linalyl acetate (22.82%), followed by α-pinene (9.82%), lavandulol acetate (7.32%), trans-caryophyllene (5.70%), and others. In total, 24 components were identified. Total phenol content was highest in water and ethanol extracts (45.3 and 14.40 mg gallic acid equivalent (GAE)/g dry extract). Polar extracts indicate good antioxidant power according to both methods, while EO can be considered as good inhibitor of AChE.

Green extraction of bioactive compounds from Azadirachta indica in aqueous glycerol and modelling and optimisation by response surface methodology

Abstract Development of efficient and green methods for extracting bioactive phytochemicals has great industrial value. Increasing environmental sensitivity at the global level has tremendously enhanced the demand for such methods. Azadirachta indica is a well-known medicinal tree. As glycerol has emerged as a green and safe extraction solvent for bioactive phytochemicals, this study aimed to investigate the efficacy of a glycerol–water solvent system to extract bioactive compounds from A. indica leaves. Modelling and optimisation were carried out by using response surface methodology (RSM) as per the Box–Behnken design with three variables, namely, solvent concentration, time and temperature. The responses were total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and metal chelating activity (MCA). The optimum conditions found by numerical optimisation were a solvent concentration of 69.713%, a time period of 38.328 min and a temperature of 32.114 °C with the predicted values of TPC, TFC, %DPPH and %MCA as 5.27 mg gallic acid equivalents · g−1 DW (dry weight), 9.869 mg rutin equivalents · g−1 DW, 73.8% and 54.366%, respectively. The validation experiments showed almost the same results for each response with very low% errors (5.431–7.661). Increasing glycerol concentration in the extracting medium favoured the extraction of TPC, TFC and antioxidant phytochemicals, but for MCA, the trend was the opposite. In conclusion, 70% aqueous glycerol is an effective medium for the extraction of polyphenolic and antioxidant phytochemicals from A. indica leaves. Extraction models suggested by RSM have high prospects to be used on a large industrial scale.

Pressurized liquid extraction of compounds from Stevia leaf: Evaluation of process variables and extract characterization

The extraction of compounds from Stevia rebaudiana leaves under pressurized conditions was investigated. The effect of the ethanol percentage in the extracting solvent, static time, pressure and temperature on global extraction yield (YGE), total phenolic content (TPC) and antioxidant activity (AA) was evaluated. The extract from pressurized liquid extraction (PLE) was characterized and compared to that obtained from Soxhlet and ultrasound-assisted extraction (UAE). It appears that the increase of ethanol concentration in the solvent favored response variables, while the increase in static time and pressure did not affect the extraction. The temperature (125 ºC) provided an increase in YGE and the highest levels of active compounds were obtained after using 70% (v/v) ethanol in the extracting solvent (15 mL g−1) and 30 min. The different techniques evaluated provided similar YGE, while PLE providing greater extraction of TPC and AA, and Soxhlet favored the extraction of steviol glycosides and total flavonoids.

Apoptosis Effects of Oxalis corniculata L. Extract on Human MCF-7 Breast Cancer Cell Line:.

Background: Recently, the non-toxic properties of natural plant products have gained more focus as anticancer agents. Therefore, this study aimed to assess the apoptosis effects of the ethanolic extract of Oxalis corniculata on the MCF-7 breast cancer cell line.Materials and Methods: In this experimental study, aerial parts of O. corniculata were collected in Lahijan city (Iran), and after confirmation, they were dried and extracted with ethanol for 24 h. Then, the total phenolic and flavonoid contents of the extract were measured. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay was used to measure the antioxidant properties of the extract. Selected cell lines (MCF-7 and human dermal fibroblast) were cultured in 6-wells dishes (1×106 cells/well). After 72 h of treating the extract, cytotoxicity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The expression of apoptotic genes (such as p53, bcl-2, bax, and CD95) was studied by real-time polymerase chain reaction (PCR). Results: The extract's total phenolic content was 31.30±02 μg of gallic acid equivalents/mg of dry extract, and the total flavonoid content was 49.61±04 μg of quercetin as equivalents/mg of extract. The antioxidant activity ofO. corniculata was measured at the dose of 619.2 μg/μl, indicating that it decreases cancer cell viability and enhances apoptosis. Within the half maximal inhibitory concentrations, real-time PCR revealed substantial increases in p53 (P<0.001), CD95 (P<0.05), and bcl-2 expression (P<0.05) in MCF-7 cells treated with O. corniculata. Conclusion: This study suggests that O. corniculata may cause apoptosis by oxidative stress in cancer cells.[GMJ.2022;11:e2484].

Extraction of phenolics and anthocyanins from purple eggplant peels by multi-frequency ultrasound: Effects of different extraction factors and optimization using uniform design

In this work, multi-frequency ultrasound (working modes for the single-, dual- and tri-frequency in simultaneous ways) was applied to extract bioactive compounds from purple eggplant peels. The single-factor experiments were performed by varying six independent variables. A six-level-five-factor uniform design (UD) was further employed to evaluate the interaction effects between different factors. It was found that extraction temperature and extraction time significantly affected the total phenolic content (TPC), whereas the total monomeric anthocyanins (TMA) was mainly influenced by ethanol concentration, extraction temperature and solid-liquid ratio. Based on partial least-squares (PLS) regression analysis, the optimal conditions for TPC extraction were: 53.6 % ethanol concentration, 0.336 mm particle size, 44.5 °C extraction temperature, 35.2 min extraction time, 1:43 g/mL solid-liquid ratio, and similar optimal conditions were also obtained for TMA. Furthermore, the TPC and TMA extraction were investigated by ultrasound in different frequencies and power levels. Compared with single-frequency (40 kHz) and dual-frequency ultrasound (25 + 40 kHz), the extraction yield of TPC and TMA with tri-frequency ultrasound (25 + 40 + 70 kHz) increased by 23.65 % and 18.76 % respectively, which suggested the use of multi-frequency ultrasound, especially tri-frequency ultrasound, is an efficient strategy to improve the TPC and TMA extracts in purple eggplant peels.

Ultrasound-assisted natural deep eutectic solvent extraction of phenolic compounds from apple pomace

ABSTRACT In this study, an environmentally friendly and efficient method based on natural deep eutectic solvent (NADES) in combination with ultrasound-assisted extraction was used for the recovery of phenolic compounds from apple pomace. Acidic, alkaline, sugar-based and polyol-based NADESs were examined for extraction of total phenolic content from apple pomace under different conditions.NADES type, biomass percentage, extraction temperature, extraction time and water content were the testing parameters. NADES type and water content of the solvent were the most important parameters that affected the extraction yield. The most effective NADESs were sugar-based NADESs, which were followed by acidic NADESs. Up to 9.47 mgGAE/gapple pomacewas recovered from apple pomace with glucose:sucrose:water. The highest total flavonoid content was obtained with choline chloride:urea as 17.30 mgEPE/gapple pomace. On the other hand, NADES composed of choline chloride – lactic acid was found to exhibit a significant antioxidant activity. The novelty of this article is the investigation of acidic, alkaline, sugar-based and polyol-based NADESs in the recovery of phenolic compounds from apple pomace using ultrasound-assisted extraction, for the first time in the literature. The antioxidant activity of extracts were also explained in combination with that of NADESs.