Total Flavonoid Content Of Extracts Research Articles

Determination of Total Flavonoid Content from Extract and Fractions of Mangrove Leaves (Rhizopora mucronata)

Indonesia is an archipelagic country with a very wide coastal area. Lombok Island has a coastal area with quite extensive mangrove forest areas. Rhizopora mucronata was the most dominant species found in the region. The Rhizopora mucronata species was a plant from the Rhizoporaceae family reported to have antibacterial, antifungal, and antioxidant activity. These biological activities were caused by the presence of secondary metabolite compounds in R. mucronata, one of which is flavonoids. Research regarding the flavonoid content of R. mucronata leaves has not been explored. Therefore, the study aimed to determine the total flavonoid content in extracts and fractions of R. mucronata leaves using the spectrophotometric UV-Vis method. R. mucronata mangrove leaves simplicia were extracted using the sonication method using 96% ethanol solvent, then fractionated using the liquid-liquid extraction method with n-hexane, ethyl acetate, and water. The percentage yield of 96% ethanol extract, water fraction, ethyl acetate fraction, and n-hexane fraction respectively were 42.33%; 43.147%; 40.49%; 9.74%; and 32.49%. The TLC test showed the presence of flavonoid compounds detected in the extract and fractions which were marked with blue spots. The total flavonoid contents in the 96% ethanol extract, water fraction, ethyl acetate fraction, and n-hexane fraction were respectively (12,980; 14,160; 23,880; and 25,350) mg Quercetin equivalent/gram sample (mg QE/ g). The total flavonoid content of the extract and fractions of R. mucronata leaves were analyzed using the One-way ANOVA test method. The total flavonoid content in the n-hexane fraction and ethyl acetate fraction was significantly higher than the 96% ethanol extract and water fraction. The total flavonoid content of R. mucronata leaves was relatively high, which contributes to several of its biological activities.

POTENTIAL ANTIOXIDANT ACTIVITY OF SURUHAN LEAF AND STEM EXTRACT (Peperomia pellucida L. Kunth) USING THE DPPH METHOD AND DETERMINATION OF PHENOLIC AND FLAVONOID LEVELS

Antioxidants are compounds that are capable of neutralizing free radicals. One plant with potential antioxidant properties is Peperomia pellucida. Objective: This study aimed to determine the antioxidant activity, total phenolic content, and total flavonoid content of extracts of the leaves and stems of Peperomia pellucida. Methods: Antioxidant activity was tested using the DPPH method, while the total phenolic and flavonoid contents were measured using UV-Vis spectrophotometry. Extraction was performed via reflux using three different solvents: n-hexane, ethyl acetate, and ethanol. Results: The highest antioxidant activity was found in the ethanol extract of the leaves, with an IC50 value of 36.85 µg/mL, and in the stems, with an IC50 value of 71.28 µg/mL. The highest total phenolic content in the ethanol extract of the leaves was 14.46 mg GAE/g and that in the stems was 12.82 mg GAE/g. The highest total flavonoid content in the ethanol extract of the leaves was 12.12 mg QE/g and that in the stems was 10.49 mg QE/g. Conclusion: The results indicated that the ethanol extract of Peperomia pellucida leaves exhibited very strong antioxidant activity. Keywords: antioxidants, DPPH, phenolic, flavonoids, suruhan Plants

Analysis of Antioxidant Capacity, Total Phenolic and Total Flavonoid Contents in Boric Acid applied Camellia sinensis L.

Consumption of Camellia sinensis L (tea), a popular beverage, is very common today. In addition to consuming tea as a beverage, it is suggested that it can also be added to other foods to increase their antioxidant activities. This study aimed to determine the antioxidant capacity, total phenolic, and total flavonoid contents of extracts prepared in different solvents of tea grown in soil treated with boric acid. The area in Rize/Turkey was divided into 4 groups. No application was made to the control group (B0 group). Boric acid prepared in sodium tetraborate buffer was applied to the other three areas as a single dose at concentrations of 100 (group B1), 300 (group B3), and 500 (group B5) mg/m2. The obtained tea leaves were ground and infused in water, 20% ethanol, and 50% ethanol by the classical infusion method. The extracts obtained after infusion were analyzed for total phenolic contents, flavonoid content, and antioxidant capacity. It was determined that 20% and 50% ethanol were a better solvent than water in terms of total phenolic content, flavonoid content, and antioxidant capacity. Although the total phenolic contents of tea leaves grown in soils treated with different doses of boric acid did not change, differences were observed in their flavonoid contents and antioxidant capacities. As a result, we can say that boric acid should be at a certain dose to improve the quality of the tea plant. In addition, different solvents can be used to reveal more of the tea content.

Phytochemical Screening, Polyphenol and Flavonoid Contents, and Antioxidant and Antimicrobial Activities of Opilia amentacea Roxb. (Opiliaceae) Extracts

Dermatoses are essentially caused by infection or free radical aggression, immunoallergic disorders, or can be secondary to general diseases. Management of dermatoses by modern medicine is complex and costly, and the development of alternative treatments is urgent. Opilia amentacea Roxb. is a woody climber plant traditionally used in Burkina Faso for treatment of bad skin diseases. This study was carried out to evaluate the antimicrobial and antioxidant activities of extracts of O. amentacea and to characterize potent fractions. The antimicrobial activity was determined using the disc diffusion and microdilution methods, while antioxidant activity was assessed using the 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) and ferric reducing antioxidant power (FRAP) assays. The content of the plant extracts in polyphenols and flavonoids was also studied. The results revealed several secondary metabolites in the leaves, stems and root bark extracts of the plant, including sterols, triterpenes, and flavonoids and tannins, and a generally high total polyphenol and total flavonoid content. Dichloromethane fractions of leaves (FDFe) and stem barks (FDET) exhibited the best antioxidant activity and were the most active on Gram-positive bacilli. Hexane leaves (FHFe) and hexane root bark (FHER) fractions exhibited the best antifungal activity against Candida tropicalis. High correlation (R2 = 0.932) was found between the total flavonoid content of extracts and ferric-reducing antioxidant power. In view of these results, the present study describes O. amentacea as a potential source of antibacterial, antifungal and antioxidant agents and justifies the traditional uses of the plant as an anti-dermatosis plant.

Determination of total flavonoid content of extract and fractions of mangrove leaves (Avicennia marina)

Determination of total flavonoid content of extract and fractions of mangrove leaves (Avicennia marina)

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 < 200 µg/mL, respectively. The positive control, ascorbic acid exhibited an IC50 value < 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.

Appropriateness of Anogessus leiocarpus leaves and bark as vegetable tannins traditionally used in leather making in Sudan

Chrome tanning industry is dominated globally owing to its high versatility in quality leather production. However, Environmental impacts of chromium have shifted the interest of present study to chrome-free options. Vegetable tannins have been proven to be environmentally safe producing good quality leather with comparable properties as that of chrome tanned leather. As such, scarcity of vegetable tannin supply demands characterization of non-commercialized sources locally available to feed local tanners. A simple extraction technique was used with different temperature 35, 50, & 85 oC. Leaves and barks from Anogessus leiocarpus grown in Sudan can produce commercially acceptable tannins in terms of extract yield, tannin, total phenolic, flavonoid contents, and crosslinking ability comparable to the extract from A. mearnsii barks, which is a worldwide known to be commercial tannin source. Results shows that temperature influences on extraction yields and tannin content was low, except for extract from Anogessus leiocarpus leaves that has shown an increase pattern with raise in temperature. Total phenolic and flavonoid content varied insignificantly with increase in extraction temperature, except for total flavonoid content of extract from Anogessus leiocarpus leaves that observed to be high at 50 oC (30.7). Variations in extract properties between extracts from plant parts studied in this work were significant. Tensile strength values of tanned skin with leaves extracts are higher than that tanned with barks. On the other hand, tanned skin with leaves extract produced greater skin elongation 40.6±0.35 compared to barks extract.

Perbandingan Kadar Flavonoid Total Ekstrak Daun Sambung Nyawa (Gynura procumbens L.) dari Simplisia dengan Metode Pengeringan yang Berbeda

The sambung nyawa leaf (Gynura procumbens L.) is a simplicia that has various properties. One of the chemical compounds in the leaves that have medicinal properties is flavonoids. Flavonoid compounds in sambung nyawa leaves have benefits as antihypertensive, antioxidant, antihyperglycemic, and anti-inflammatory. The difference in the simplicia drying method had an effect on the total flavonoid content contained in the extract. The aim of the study was to measure the total flavonoid content of sambung nyawa leaf extract from simplicia dried by wind drying and oven drying at 40°. The research method is an experimental study by measuring the total flavonoid content of the extracts of sambung nyawa leaves from wind-dried and oven-dried simplicia using UV-Vis Spectrophotometry. The results showed that the total flavonoid content of the extract from the wind-dried sambung nyawa was 42.64 mg/g and 40°C oven-dried was 50.14 mg/g. It was concluded that sambung nyawa leaves dried in an oven at 40°C produced extracts with higher total flavonoid content than wind-dried simplicia.

Combination of ethanolic extract on total flavonoid Centella asiatica L. leaves and Imperata cylindrica L. roots with UV-VIS spectrophotometric method

Background: Flavonoids are widely employed as phytomedicines and as secondary metabolites generated by plants, where they serve key roles in plant physiology. Antioxidant, anti-inflammatory, anticancer, antibacterial, antifungal, and antiviral activities are only a few of the potential biological effects of flavonoids. The discovery of medicinal plants containing flavonoid chemicals is potential as a supportive and preventative treatment, notably for COVID-19 which has caused a pandemic in several countries, including Indonesia.Objective: This study aimed to determine the total flavonoid content in the ethanolic extracts of C. asiatica leaves and Imperata cylindrica roots to find the potential of flavonoid-rich plants as an alternative source of COVID-19 treatment.Methods: The ethanolic extracts from the combination of C. asiatica leaves and I. cylindrica roots (with five combination ratios) were tested for total flavonoid content using the UV-Vis Spectrophotometry method. The total flavonoid content of the extract combination was analyzed using a one-way ANOVA test.Results: The total flavonoid contents of the combination of C. asiatica leaf and I. cylindrica root extracts at a ratio of 1:1, 2:3, 3:2, 4:1, and 1:4 were 45.88 ± 0.08, 42.14 ± 0.08, 40.52 ± 0.08, 66.28 ± 0.08, and 40.88 ± 0.13 mg/g EQ, respectively. The homogeneity with Levenes test obtained a p-value of 0.303. The one-way ANOVA exhibited the p-value of F-test statistics Conclusion: The total flavonoid contents of ethanolic extracts from C. asiatica leaves and I. cylindrica roots are at a ratio of 4:1 > 1:1 > 2:3 > 1:4 > 3:2. The high total flavonoid content plays a role in increasing anti-inflammatory and immunomodulatory activities in COVID-19 patients.Keywords: Total flavonoid content, C. asiatica, I. cylindrica, UV-Vis Spectrophotometry, COVID-19

Oxidative Potential and Nanoantioxidant Activity of Flavonoids and Phenolic Acids in Sophora flavescens.

In order to further develop and utilize the rutin from Sophora japonica, the contents of total phenolic acids and flavonoids in rutin extracts from different parts of Sophora flavescens were determined, and their antioxidant activities were compared, and the basis of antioxidative activity of Sophora flavescens nanometers was discussed. The experiment found that the total flavonoid content of each extract of Huai Mi was in the range of 5.70–61.55 mg/g, the total phenolic acid content was in the range of 4.07–19.10 mg/g, and the total flavonoid and phenolic acid content of the ethyl acetate extract was significantly higher than other extracts. Its reducing power, light free radicals, DPPH, ABTS+, and scavenging rate are also significantly higher than n-butanol, petroleum ether, and aqueous extracts. ∗The cleaning ability IC50 values of DPPH· are (0.321 ± 0.0026), (0.213 ± 0.0010), and (0.169 ± 0.0014) mg/mL. The effective components of Sophora japonica are initially separated after the solvent extraction of each phase. The relative content and nanoantioxidant activity of total flavonoids and phenolic acids in the ethyl acetate phase extraction part were significantly stronger than those in the total extract and other extraction parts, and the antioxidant capacity was effectively related to the dose. The flavonoids and phenolic acids in Sophora japonica are closely related to its antioxidant capacity.

Phytochemical Profile and Pharmacological Activity of Vernonia amygdalina Delile Stem Bark Extracts Using Different Solvent Extraction

BACKGROUND: Vernonia amygdalina is a native plant from Africa which is widely distributed to Asia, especially in Indonesia. Parts of V. amygdalina such as roots, leaves, and bark are used by the community as traditional medicines such as antidiabetic, antibacterial, and anticancer. AIM: This study aims to show the effect of solvents in the V. amygdalina stem bark extraction process on phytochemical’s content and their correlation with pharmacological activities. METHODS: V. amygdalina extract from stem bark in this study was obtained using the maceration method with different solvents. The extracts were investigated for total phenolic content (TPC) and total flavonoids content (TFC) using calorimetry assay. Principal Component Analysis (PCA) was used to grouping the extracts based on Fourier-transform infrared (FTIR) data. Antioxidant activity of the extracts was done using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis (3-ethyl benzhothiazoline sulphonic acid) (ABTS) assay. While, the cytotoxic activity of the extracts was carried out using MTT assay on PANC-1 cell line. The correlation phytochemical content and pharmacology activities of extracts were analyzed using person correlation method. RESULTS: There were significantly different TPC and total flavonoid content of extracts (p < 0.05). The ethyl acetate extract was identified to have the highest TPC, TFC, DPPH, ABTS, and cytotoxic values of 3.61 ± 0.03 mg GAE/g dry powder, 25.12 ± 0.09 mg QE/g dry powder, 27.12 ± 0.65 μg/mL, 67.02 ± 0.23 μg/mL, and 33.83 ± 0.82 μg/mL, respectively (p < 0.05). This is supported by PCA analysis which shows that there are differences in extracts based on FTIR data and there is a strong correlation between TPC and TFC values with antioxidant and cytotoxic activities. CONCLUSIONS: This study report that each extract of V. amygdalina stem bark gives a distinct phytochemical profile (TPC, TFC, and FTIR spectrum) that contributes to the antioxidant activity and cytotoxic activity.

Microscopic Identification and Determination of Total Flavonoid Content of Moringa Leaves Extract and Ethyl Acetate Fraction (Moringa oleifera L.)

This research was conducted to identify simplicia microscopically, phytochemical screening and determination of total flavonoid content of extract and ethyl acetate fraction from Moringa (Moringa oleifera L.) leaves using UV-Visible Spectrophotometry method. The experimental design used in this study was to perform microscopic identification of Moringa leaf powder simplicia, make 96% and 70% ethanol extract and ethyl acetate fraction of Moringa leaves from 70% ethanol extract, then carry out phytochemical screening and determination of total flavonoid content with quercetin standards. Phytochemical screening on the ethyl acetate fraction of Moringa leaves included tests for the content of flavonoids, saponins, tannins and alkaloids. The results of microscopic identification of Moringa leaf simplicia showed the presence of calcium oxalate crystals in the form of rosettes, mesophyll and stomata. The result of determination of total flavonoid content in 96% ethanol extract was 16.69 ± 0.74% (w/w), 70% ethanol extract was 10.84 ± 0.49% (w/w), Moringa leaf ethyl acetate fraction 14 .45 ± 0.90% (w/w). The highest total flavonoid content was found in the 96% ethanol extract of Moringa leaves in accordance with the 2017 Indonesian Herbal Pharmacopoeia, that the thick extract of Moringa leaves containing no less than 6.30% (w/w) total flavonoids was calculated as quercetin.

Determination of Antiradical Activity, Total Phenolic, and Total Flavonoid Contents of Extracts and Fractions of Langsat (Lansium domesticum Coor.) Seeds

Lansium domesticum Coor. is a fruit species from the Meliaceae family, which is a tropical plant native to Southeast Asia. Local citizens call it langsat, longkong, or duku and have used it as traditional medicine. The seeds of L. domesticum are used as a fever medicine, its bark is used to treat scorpion sting, and its leaves are used to repel mosquitoes. Because of its various uses, it is necessary to explore the antiradical potential of L. domesticum seeds. This study aims to determine the antiradical potential of L. domesticum seeds extract and fractions by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and to discover compounds that act as antiradical. Lansium domesticum seed powder was macerated with methanol, and then the extract was concentrated using a rotary evaporator and fractionated by n-hexane and ethyl acetate. The antiradical assay was conducted on extract and fractions by using DPPH radicals. Phenolic and flavonoid contents from extract and fractions were also tested. The ethyl acetate fraction obtained strong antiradical potential with an IC50 value of 8.938 � 0.031 �g/mL. Total phenolic and flavonoid contents of ethyl acetate fraction were higher with values ??of 58.25 � 0.501 mgGAE/g sample and 75.123 � 0.175 mgQE/g sample, respectively. Correlation of phenolic and flavonoid contents, which inhibited radicals had R2 values ??of 0.9182 and 0.7658. Ethyl acetate fraction of L. domesticum seeds had very strong antiradical activity. Further isolation is expected to be conducted to discover which compounds are the most responsible as antiradical.

Launaea acanthodes (Boiss) O. Kuntze mediates hepatic glucose metabolism and ameliorates impaired pancreatic function in streptozotocin-induced diabetic rats

Ethnopharmacological relevanceLaunaea acanthodes (Boiss.) O. Kuntze is native to semiarid regions of central Iran, traditionally used in the treatment of numerous disorders including diabetes. Aim of the studyThe current study aimed to explore hypoglycemic activity of Launaea acanthodes extract in streptozotocin-induced diabetic rats. Furthermore, gene expression study was carried out to examine expression levels of key glucose metabolism-related genes. MethodsFor in vitro study, Folin-Ciocalteus, DPPH and aluminum chloride colorimetric assays were used to determine the total phenolic content, antioxidant capacity and total flavonoid content of extracts, respectively. For in vivo study, streptozotocin-induced diabetic Wistar rats were orally administered with metformin (50 mg/kg) and various doses of extracts (100, 200 and 400 mg/kg body weight) for 28 days. Fasting blood glucose, body weight, food and water intake were assessed during the course of treatment. At the end of the intervention, oral glucose tolerance test (OGTT), lipid profile and glycated hemoglobin (HbA1c) were evaluated. Furthermore, functional liver enzymes, oxidative stress markers and histopathology of pancreas were examined. Lastly, quantitative real time polymerase chain reaction (qRT-PCR) was applied to explore the mRNA levels of genes relevant to glucose metabolism in the pancreas and liver tissues of diabetic rats. ResultsBased on the in vitro results, the hydroalcoholic extract revealed potential radical scavenging activity and contained highest amount of phenolic and flavonoid. The in vivo results demonstrated that the extract lowered fasting blood glucose level, increased the body weight, restored the alterations in the levels of water and food intake, attenuated HbA1c, improved lipid profile and ameliorated the OGTT in diabetic rats. The extract administration alleviated the histopathological changes in the pancreas, suppressed malondialdehyde (MDA) level and further restored attenuated levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) in diabetic rats. Analysis of real time PCR data showed that extract administration reversed the expression levels of hepatic glucokinase (GK), phosphenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase). Meanwhile, the extract upregulated the expression level of glucose transporter-2 (GLUT-2) and pancreatic-duodenal homeobox (PDX-1) in diabetic rats. ConclusionCollectively, the results demonstrate that Launaea acanthodes hydroalcoholic extract exerts hypoglycemic effect possibly via regulating key enzymes of glucose metabolism and ameliorating pancreatic dysfunction through its antioxidant properties.

Determination of Total Flavonoid Contents and Antioxidant Activity of Leucaena Leucocephala Leaves's Extract

The study of the determination of total flavonoid contents and antioxidant activity of extract of Leucaena leucocephala leaves had been carried out using UV-Vis spectrophotometry method. This study aimed to determine the total flavonoid contents and the antioxidant power of Leucaena leucocephala extract. Extraction of chemical content from Leucaena leucocephala was carried out by the maceration method using absolute ethanol. The total flavonoid contents from the sample extract were taken up for absorption at wavelength 510 nm and 700 nm. The variation of the concentration of Leucaena leucocephala leaves' extract was respectively 20, 40, 60, and 80 ppm. The results of the study showed that the total flavonoid contents of extracts of Leucaena leucocephala leaves was 2.242 g/100 grams. The antioxidant activity of Leucaena leucocephala leaves extract was carried out using DPPH (1,1-diphenyl-2-picrylhydrazine) and the measurement of absorption was at a wavelength of 517 nm, and by varying the sample concentration. Positive control used was vitamin C solution with the same variation of extract's concentration. The results showed that the IC50 values of Leucaena leucocephala leaves extract and vitamin C were 175.388 and 28.907 ppm. Based on the IC50 data it can be stated that the antioxidant vitamin C was stronger than the Leucaena leucocephala leaves extract which was classified as a weak type of natural antioxidant.

Eco-friendly “green” synthesis of silver nanoparticles with the black currant pomace extract and its antibacterial, electrochemical, and antioxidant activity

This work reports a “green” method where silver nanoparticles (AgNPs) were synthesized using silver nitrate and the aqueous extract of black currant pomaces (BCPE). LC–MS spectrum showed the presence of 16 compounds with chlorogenic acid and caffeic acid as the dominant components of BCPE. Total phenolic content and total flavonoid content of extracts were determined. Various experimental techniques including iron (III) reducing capacity, total antioxidant capacity, and DPPH radical scavenging activity were used to characterize antioxidant activity of the extract. Scanning electron microscopy (SEM) and EDX analysis showed that silver nanoparticles were pure and polydisperse. The synthesized nanoparticles might serve as a potent antioxidant as revealed by DPPH assay. The synthesized nanoparticles (BCPE–AgNPs) efficiently inhibit pathogenic organisms such as Gram-negative bacteria.

Green Synthesis of Silver Nanoparticles Using Waste Products (Apricot and Black Currant Pomace) Aqueous Extracts and Their Characterization

An eco‐friendly and low‐cost method for synthesizing and capping silver nanoparticles with aqueous extracts of apricot and currant wastes is reported. The chemical profiles of the extracts were analysed using liquid chromatography‐mass spectrometry (LC‐MS). Total phenolic content and total flavonoid content of extracts were determined. The antioxidant activity of the synthesized nanoparticles was evaluated by DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) power assays. Cyclic voltammetry study was performed to determine the reducing ability of the aqueous extract of the black currant and apricot pomaces. Characterization of AgNPs was carried out using energy‐dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and UV‐visible spectroscopy. Zeta potential of obtained colloidal solutions varies from −33.41 to −24.23 mV indicating the moderate stability of synthesized nanoparticles. The synthesized nanoparticles efficiently demonstrated a bactericide effect on Escherichia coli.

Characterization of Chemical Compounds and Antioxidant Activity of Centaurea solstitialis sp. schouwii (DC.) Q. et S. (Asteraceae)

Background:The antioxidant activity and the total phenolic and flavonoid contents of the derived extracts (chloroform, ethyl acetate and n-butanol) of the 70% hydroalcoholic extract of the aerial parts of Centaurea solstitialis growing in Algeria was assessed. The active extracts were selected for phytochemical investigations.Methods:The antioxidant capabilities of the extracts were assessed using 1, 1-diphenyl-2- picrylhydrazyl radical (DPPH•) scavenging and Cupric Ion Reducing Antioxidant Capacity (CUPRAC) assays. Butylhydroxyanisole (BHA), butylhydroxytoluene (BHT) and α –tocopherol were used as positive controls. The total phenolic content and total flavonoid content of the extracts were determined as gallic acid equivalents and quercetin equivalents, respectively. Chromatographic methods were used to isolate the secondary metabolites and spectrometric and spectroscopic methods were used to determine their chemical structures.Results:The ethyl acetate extract exhibited the highest antioxidant activities followed by the n-butanol extract. The highest phenolic and flavonoid contents were found in the n-butanol extract. Phytochemical study of the ethyl acetate and n-butanol extracts led to the isolation of an undescribed guaianolide named 3-(4-hydroxybenzoyl)-cynaratriol and a known sesquiterpene lactone along with three known flavonoid glycosides. Their structures were established by spectral analyzes mainly high resolution electrospray ionisation mass spectrometry (HR-ESIMS) and 1D and 2D nuclear magnetic resonance experiments.Conclusion:The extracts of aerial parts of C. solstitialis showed significant antioxidant activities. An undescribed sesquiterpene lactone and four known secondary metabolites were isolated from the most active extracts.

Boiling increase antioxidant activity, total phenolic content and total flavonoid content in Plectranthus amboinicus leaves

The effect of boiling on antioxidant activity, total phenolic content (TPC) and total flavonoid content (TFC) in the ethanol extracts from Plectranthus amboinicus leaves were studied. The dried leaves were boiled in water for 0 (control), 30, 60, 90 and 120 minutes, then extracted with ethanol to produce ethanol extracts. The ethanol extracts were subjected to three antioxidant assays, i.e., 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP). TPC and TFC in extracts were determined by Folin-Ciocalteu assay and aluminium chloride colorimetric assay, respectively. The results of DPPH, ABTS and FRAP assays indicated that the antioxidant of extracts were significantly (p < 0.05) more potent than the control and also increased when the boiling time was increased. Furthermore, TPC and TFC in extracts from boiled samples were significantly (p < 0.05) higher than the control and correlated with antioxidant activity. This study revealed that boiling of P. amboinicus leaves were increased its antioxidant activity, TPC and TFC as determine in ethanol extracts, and suggested that boiling can be used as a method for enhancing antioxidant activity of P. amboinicus.

Phytochemical and Biological Studies of Scrophularia striata from Ilam

Background: Medicinal plants have been considered a suitable source for finding new pharmaceutical chemicals, and identification of chemical composition is the first step towards uncovering the nature of bioactive compounds. Objectives: Scrophularia striata is used to treat various infections in traditional medicine. The aim of this study was to evaluate phytochemical and biological analysis of S. striata collected from Ilam. Methods: In the present study, the hydro distilled volatile oils of aerial parts of S. striata were investigated by GC-MS and GC-FID. The total phenolic and total flavonoid content of hydro-alcoholic extract of S. striata were measured by the Folin-Ciocalteu and aluminium chloride colorimetric method, respectively. The antioxidant activity of hydro-alcoholic extract was studied by using the 2,2-diphenyl-1-picrylhydrazyl assay. Results: In total, 26 compounds were identified and the main identified compounds of the essential oil were n-hexane (16.3), caryophyllene oxide (15.36), spathulenol (13.1), α-cadinol (12.35), and docosane (6.33). The hydro-alcoholic extract showed moderate antioxidant activity with IC50 =85μgmL-1. The total phenolic content of extractwas15.9mggallic acid equivalents/g dry weight, and the total flavonoid content of extract was 1.8 mg quercetin/g dry weight. Conclusions: The data of this study suggests that the essential oil and hydro-alcoholic extract of S. striata could be considered a natural antioxidant agent to preserve food and treat infections in food and pharmaceutical industry. In addition, the data of this study can be used for further studies on the taxonomy of Scrophularia genus. © 2018, Jundishapur Journal of Natural Pharmaceutical Products.