Determination Of Flavonoid Content Research Articles

Antioxidant and bio-activities of leaf extracts from Eucalyptus globulus

Eucalyptus globulus member of Myrtacaea family, is one of the important medicinal widely used plant.In this study methanolic leaf extract of Eucalyptus globulus was studied for the estimation of phytochemical constituents , in-vitro antioxidant and anti-inflammatory activity . Fresh leaves were ground with methanol used for estimations. Phytochemical constituents were estimated by total phenolic content and total Flavonoid content determination. Spectroscopic analysis by UV-VIS, FT-IR and fluorescents analysis was also conducted. In vitro anti- inflammatory and antimicrobial activities were also monitored.Phytochemical screening revealed the presence of flavonoids , phenols , carbohydates and saponins. Considerable amount of phenolics (50 mg equivalent par g of dry weight) and flavonoids (23 mg equivalent par g of dry weight) were detected in extract. Extract exhibited considerable DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS (2,2’-azinobis-3-ethylbenzothiazoline-6-sulphonate) scavenging activities, Hydroxyl radical scavenging activity, Nitric oxide radical scavenging activity , Iron reducing power and Superoxide radical scavenging activity. Fluorescent spectroscopy revealed the presence of fluorophores in extracts. A strong anti-inflammatory activity of extract was observed using fluorescent spectroscopy. An appreciable in vitro antibacterial activity against gram-negative bacteria like gram-negative bacteria Escherichia coli, MTCC 40 was detected. This study confirmed that methanolic extract Eucalyptusglobulus possesses potent antioxidant anti-inflammatory and antibacterial activities possibly important quantity of flavonoid and phenolic content present in it .

Anti-adipocyte differentiation activity and flavonoid content determination by HPLC/UV analysis of tree sprouts

Anti-adipocyte differentiation activity and flavonoid content determination by HPLC/UV analysis of tree sprouts

PENETAPAN KADAR FLAVONOID FRAKSI ETIL ASETAT DAUN KARET KEBO (Ficus elastica) DENGAN METODE SPEKTROFOTOMETRI UV-VIS

Rubber plant ( Ficus elastica ) is a plant that has been widely used as traditional medicine. The leaves of this plant are used as medicine for coughing up blood, laxative urine, relieving pain and improving blood circulation. Various kinds of properties and benefits of the rubber plant ( Ficus elastica ) cannot be separated from the compounds contained in it such as saponins, polyphenols, and flavonoids. The aims of this research is to determine the flavonoid total content in the ethyl acetate fraction of the rubber leaves ( Ficus elastica ). Simplicia was extracted by maceration method, using 96% ethanol solvent for 3x24 hours and partitioned with a mixture of 96% ethanol - aquadest (2:3) and ethyl acetate as a solvent. Determination of flavonoid content using UV-Vis spectrophotometry method , with a maximum wavelength of 438 nm, using quercetin as a comparison. The results of this research obtained that the total flavonoid content in the ethyl acetate fraction of rubber leaves ( Ficus elastica ) was an average of 74,345 mgQE/g fraction

Determination of Phenolics and Flavonoids of Some Useful Medicinal Plants and Bioassay-Guided Fractionation Substances of Sclerocarya birrea (A. Rich) Hochst Stem (Bark) Extract and Their Efficacy Against Salmonella typhi.

Gallic acid and catechin are the most abundant phenolic and flavonoid contents found in all plant extracts. The contents and the bioassay-guided fractionating substances of the Sclerocarya birrea (A. Rich) Hochst (Anacardiaceae) fraction played vital roles. The goals of the study were to determine the contents of some useful medicinal plants and the bioassay-guided fractionation substances of S. birrea fraction compounds capable of acting against Salmonella isolate using LC-MS/LC-HRMS (Dionex ultimate 3000 RS UPLC with Thermo Scientific Q Exactive Orbitrap Hybrid Tandem Mass Spectrometer). The Folin–Ciocalteu reagent procedure and flavonoid content determination were conducted spectrophotometrically. Bioassay-guided fractionation, chronological partitioning, and screening of the antibacterial action against Salmonella typhi were performed. The ethyl acetate fraction extracts of S. birrea stem (bark) extract were analyzed using LC-MS/LC-HRMS. The gallic acid content increased tremendously in Vachellia nilotica (L.) P.J.H. Hurter and Mabb (Fabaceae) pod extracts with curve fitting (R 2 = 0.9958). Catechin content increase was significantly increased in S. birrea stem (bark) extracts followed by that of V. nilotica pod extracts with curve fitting (R 2 = 0.9993); they were all significantly different in the Guiera senegalensis J.F. Gmel. and the Leptadenia lanceolata (Poir.) Goyder leaves extracts at p value <0.0001. Subsequently, 10 mg/ml of S. birrea stem (bark) ethyl acetate fraction extract was the MIC, where no MBC was recorded and susceptible to the positive control with the highest inhibition zone, followed by the ethyl acetate fraction extract at 10 mg/ml (9.7 ± 0.0) at Turkey’s p < 0.0001. Vidarabine is one of the novel compounds, specifically having antimicrobial actions, found in the S. birrea stem (bark). Reasonable amounts of phenolic and flavonoid contents determined the actions of the individual plant extract.

In vitro antioxidant activity test and determination of phenolic and flavonoid content of Moringa oleifera pulp and seeds

Moringa oleifera is a plant that is empirically widely used as a medicine to treat hyperglycemia, anti-inflammatory, antidiabetic, antimicrobial, anticancer, antioxidant, gastric ulcer, skin disease, fever, fatigue, hysteria, thrush, bladder, and bronchitis. Moringa oleifera contains secondary metabolites such as flavonoids, tannins, terpenoids, alkaloids, and phenolics. This study aimed to investigate the antioxidant activity and levels of phenolic and flavonoids in the extracts and fractions of moringa pulp and seeds. The pulp and seeds of Moringa were extracted using the maceration method and fractionated using the liquid-liquid extraction method. Antioxidant activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Phenolic content was measured using the Folin-Ciocalteau method. Meanwhile, the flavonoid content was determined using the AlCl3 colorimetric method with UV-Vis spectrophotometry. The ethyl acetate fraction of moringa pulp and seeds had the strongest antioxidant activity with IC50 values of 5.97 µg/mL and 5.08 µg/mL, respectively. Ethyl acetate fraction also has high phenolic and flavonoid content in the pulp and seeds of moringa with a phenolic content of 43.956 mg GAE/g sample for pulp and 9.429 mg GAE/g sample for moringa seeds. The flavonoid content of 94.257 mg QE/g sample for pulp and 93.719 mg QE/g sample, with the highest correlation between phenolic compounds and flavonoids on antioxidant activity, was obtained in moringa pulp with the highest correlation (R2 = 0.6514) for phenolic and R 2 = 0.7531) for flavonoids. In conclusion, the ethyl acetate fraction of moringa pulp and seeds can be further developed as an antioxidant and functional food.

Examination the antioxidant potentials and antidiabetic properties of phenolic extracts of some Iranian honeys

Introduction: In most ancient cultures, honey has been used for both nutritional and medical purposes. Objectives: In this research, phenolic extracts of four Iranian honeys were evaluated to determine the antioxidant potentials using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, nitric oxide (NO) radical scavenging and reducing power by ferric reducing activity of plasma (FRAP) method. Additionally, anti-diabetic properties of honey and phenolic extracts were evaluated by determination of α-amylase and α-glucosidase inhibition. Patients and Methods: Besides, reducing potential was evaluated by ferric-reducing antioxidant power method. Moreover, determination of phenolic and flavonoid contents was performed. Moreover, inhibition of α-amylase and α-glucosidase of honey and phenolic extracts were evaluated. Results: With considering to antioxidant potentials, Gavan (Astragalus) sample showed the greatest phenolic (3817±1.52 mg GAE/100 g), flavonoid contents (3.1±0.005 mg QE/100 g), and DPPH radical scavenging (IC50 = 2±0.003 mg/mL). Bahareh honey had the highest NO radical scavenging (IC50=0.0403±0.0009 mg/mL) and Meymand honey possessed the highest reducing potential by FRAP method (IC50=0.0018±0.000003 mg/mL). The maximum inhibition of α-glucosidase was shown in Meymand honey extract (46±0.1%). After sugar isolation, Zataria honey had the highest inhibition of α-glucosidase (54±0.6%) and the mode of α-amylase inhibition was noncompetitive by this honey. Whole extract (23±0.1%) and phenolic extract of Gavan honey presented the maximum inhibition of α-amylase (31.2±0.1%). Conclusion: Honey samples showed antioxidant potentials and anti-diabetic properties by retardation of α-amylase and α-glucosidase.

Development and validation of spectrophotometric methods for quantitative determination of total phenolic and total flavonoid content of lyophilizate of the leaf of sweet potato leaf

Sweet potato (Ipomoea batatas L.) is one of the plants commonly used as traditional medicine, such as anti-inflammatory, anti-diabetes, anti-mutagenic and to increase platelet count. The benefits of sweet potato leaves have been reported as a result of the presence of antioxidant compounds and bioactive compounds, mainly phenolic and flavonoid compounds. In this study, we validated the spectrophotometry method of total phenolic and flavonoid compound of lyophilizate of the leaves of sweet potato juices. The results showed that the coefficient correlation (r) values were 0.97389 for gallic acid standard and 0.99869 for quercetin standard; the recovery rates ranged from 105.08% to 109.92% for phenolic, and from 87.48% to 94.36% for flavonoids respectively; precision with relative standard deviation values ranged from 0.7% to 0.4% for phenolic, and from 0.9% to 0.5% for flavonoids respectively; and the detection limit (LOD) and the quantitation limit (LOQ) for phenolic were 0.0425 μg/mL and 0.128 μg/mL respectively while for flavonoids were 0.17 μg/mL and 0.5 μg/mL respectively. The method was successfully applied in the determination of phenolic and flavonoid contents of lyophilizate of sweet potato leaf juices with the average total phenolic content of 9.83mg GAE/g lyophilizate, while the average total flavonoid level was 5.11mg QE/g lyophilizate.

Determination of phenolics composition, antioxidant activity, and therapeutic potential of Golden marguerite (Cota tinctoria)

Yellow chamomile (Cota tinctoria) is used for dye production in food industries and some health benefits as an herbal tea. This work was designed to comprehensively evaluate phenolic profiling, antioxidant activity, and therapeutic target enzymes' inhibitory effect of C. tinctoria using chromatographic and spectroscopic methods. High-performance liquid chromatography analysis and total phenol and flavonoid content determination were performed to investigate phenolics composition and concentration. Chlorogenic acid (6518 and 8338 µg/g extract), rutin (752 and 1196 µg/g extract), catechin (764 and 804 µg/g extract), and apigenin (662 and 164 µg/g extract) were determined as the major phenolics of methanolic extract and infusion, respectively. The antioxidant ability of methanolic extract and infusion of the herb was tested using six different mechanisms. Promising antiradical properties were recorded in DPPH and ABTS test (125–275 mg Trolox equivalents/g sample). Also, methanolic extract and infusion exhibited high reducing power (207–350 mg TE/g sample). Moreover, yellow chamomile showed moderate cholinesterase inhibitory (0.2–1.7 mg GALE/g extract), antidiabetic (0.06–0.55 mmol AE/g extract), and tyrosinase inhibitory (11.12 mg KAE/g extract) activities. Results suggested that this plant could be used more in food and pharmaceutical products due to its valuable ingredients and biological activities.

Spectrophotometric Determination of Total Flavonoid Content in Biancaea Sappan (Caesalpinia sappan L.) Leaves

AbstractBiancaea sappan (BS) is traditionally used to treat anticonvulsants, anti-inflammatory, antiproliferative, anticoagulant, antiviral, immunostimulant, antioxidant, and antimicrobial treatments. Flavonoids are found in Secang; flavonoids are secondary metabolites that have antioxidant activity. This study aims to identify the flavonoids using TLC and determination of flavonoids content in BS leaves. Initially, The methanol extract of BS was obtained by maceration with ethanol. The qualitative analysis of flavonoid was using TLC and visualization by sprayed with AlCl3. The determination of total flavonoid content is conducted based on the AlCl3 method with total flavonoids expressed in QE (Quercetin equivalent) at the maximum wavelength of 431 nm. The research results showed that BS leaves contain flavonoids and the total flavonoid content of BS leaf extract is 1.0318 mg QE / g extract.Keywords: Caesalpinia sappan; Flavonoid content, Spectrophotometric

Quantitative Analysis of Flavonoids in Glycyrrhiza uralensis Fisch by 1H-qNMR.

Objective To establish a method for simultaneous determination of liquiritin, liquiritigenin, and isoliquiritinin glycyrrhizin using hydrogen nuclear magnetic resonance quantitative technology (1H-qNMR). Methodology. Deuterated dimethyl sulfoxide was used as the solvent, and dichloromethane was used as the internal standard. The probe temperature was 298.0 K, the pulse sequence was Zg30, the number of scans was 16, and relaxation delay (D1) was 10 s. Quantitative characteristic signal peaks were δ 4.891∼4.878 ppm, δ 8.187∼8.172 ppm, and δ 6.790∼6.776 ppm for liquiritin, isoliquiritin, and liquiritigenin, respectively. Results The experimental result showed that the content of flavonoids in Licorice, from Chifeng, Inner Mongolia, was the highest. Conclusion In this study, a new method for determination of three flavonoids in Licorice using 1H-qNMR was established. This experimental method has the advantages of accuracy, efficiency, and economy. It lays a foundation for the study on the determination of flavonoids content in licorice by proton nuclear magnetic resonance spectroscopy.

Investigation on phytochemical composition, anti-oxidant and anticancer properties of methanolic extract of Phyllanthus niruri schumach & thonn. And protein modelling and drug docking

The study aims to investigate the Phytochemical Composition, Anti-oxidant and Anticancer properties of methanolic extract of Phyllanthus niruri Schumach &amp; Thonn And the Protein Modelling and drug docking. The research deals with the methanolic extraction and phytochemical screening, determination of total phenolic and flavonoids contents and anti-oxidant assay. By performing GC-MS characterisation, various active metabolites are analysed. Thin-layer chromatography profiling of the Phyllanthus niruri methanolic extract was performed. The IC50 of the Phyllanthus niruri methanolic extract against PA-1 Cell lines(Ovarian cancer) was calculated. Docking studies also performed for antitumor activity by using Bioinformatics and Cheminformatics software on corilagin and cisplatin. The results suggested that the methanolic extract of Phyllanthus niruri leaves has the anticancer cancer effect on the ovarian cell line. The docking studies also performed that Corilagin interaction with T.F. receptor shows a high binding score when compared to cisplatin. Our future research can be done in this area to optimise anticancer activity efficacy. Our results can be further tested Clinico-pharmacologically to prove its efficiency in human beings.

Validation of an optimized HPLC/UV method for the quantification of flavonoids in lotus

Flavonoids present in the leaves of lotus (Nelumbo nucifera) grown in different regions of South Korea (Yeongcheon, Haenam, and Seocheon) and at different harvest times (July to September) were determined. Flavonoid contents in lotus extracts were identified and analyzed using high-performance liquid chromatography (HPLC). The HPLC results revealed that the flavonoid contents of the lotus extracts varied at different harvesting times, with the highest content in July. Analysis of the flavonoid content in the leaves from the different regions showed the highest contents of isorhamnetin-3-O-glucoside, quercetin 3-O-glucuronide, and quercetin 3-O-glucoside in Yeongcheon, Korea, and highest contnts of rutin, myricetin, kaempferol 3-O-glucoside, and quercetin in Haenam, Korea. The HPLC method was validated and optimized to quantify quercetin 3-O-glucuronide; it showed good linearity (1000–62.5 µg/mL, r2 = 0.9999), accuracy (106%–108%), and precision (RSD ≤ 1.70%). Determination of flavonoid content in lotus is valuable for producing medicinal crops and identifying the optimal sources to increase the quantity of clinically available medicines.

Effect of Aqueous Warionia saharae Extract on Lipid and Glucose Metabolism in Normal and Diabetic Rats

Objective:The aim of the study was to evaluate the hypolipidemic and antioxidant properties of aerial parts aqueous extract of Warionia saharae (APAE of W. saharae) in normal and streptozotocin (STZ) induced-diabetic rats. Additionally, the quantitative and qualitative analysis for the presence of different phytochemical constituents in the APAE of W. saharae was performed.Methods:The effects of oral administration of APAE of W. saharae (5 mg/kg) on the plasma Total Cholesterol (TC) and triglyceride (TG) levels were measured in both normal and diabetic rats. Moreover, the antioxidant capacity was realized by the method of DPPH. Total polyphenol as x of the APAE of W. saharae were determined.Results:APAE of W. saharae showed a strong hypolipidemic and antihyperglycemic effects both in normal and in STZ induced diabetic rats. On the other hand, APAE of W. saharae showed a potent antioxidant activity and revealed inhibitory activity. Moreover, the quantitative determination of total polyphenol and flavonoid contents showed high contents of these phytochemicals. Concerning the qualitative analysis several classes of chemicals have been found.Conclusion:APAE of W. saharae (5 mg/kg) shows the potential cholesterol and glucose lowering activity as well as antioxidant properties in both normal and STZ-induced diabetic rats.

Pengaruh Metode Ekstraksi terhadap Kadar Fenol dan Flavonoid Total, Aktivitas Antioksidan serta Antilipase Daun Jati Belanda (Guazuma ulmifolia)

Daun Guazuma ulmifolia telah digunakan secara tradisional untuk antiobesitas. Aktivitas antiobesitas dipengaruhi oleh kandungan senyawa bioaktif. Ekstraksi adalah langkah utama untuk mendapatkan senyawa bioaktif. Metode dan pelarut ekstraksi merupakan faktor penting untuk menghasilkan ekstrak dengan jumlah kandungan senyawa aktif yang tinggi. Penelitian ini bertujuan untuk menentukan kadar fenol dan flavonoid total dari ekstrak etanol, rebusan, dan infusa daun G. ulmifolia serta untuk menentukan aktivitas antioksidan serta antilipase. Metode Folin-Ciocalteu digunakan untuk menentukan kadar fenol total, sedangkan penentuan kadar flavonoid total dilakukan menggunakan uji kolorimetri aluminium klorida. Aktivitas antioksidan ditentukan dengan metode 2,2-difenil-1-pikrillhidrazil (DPPH), dan aktivitas antilipase dikuantifikasi secara kolorimetri berdasarkan pelepasan p-nitrofenol dari substrat p-nitrofenil butirat (p-NPB). Hasil penelitian menunjukkan bahwa rebusan memiliki rendemen tertinggi (10,50%). Sebaliknya, ekstrak etanol menunjukkan total kandungan fenolik tertinggi (67,761 ± 1,811 mg GAE/g ekstrak) dan total kandungan flavonoid tertinggi (124,643 ± 1,033 mg QE/g ekstrak). Ekstrak yang sama juga menunjukkan aktivitas antioksidan dan aktivitas antilipase tertinggi (IC50 berturut-turut 6,544 ± 0,271 μg/mL dan 307,280 ± 21,430 μg/mL).

Pharmaceutical Development of «Sedoflav» Capsules, Standardization and Validation of Flavonoids Assay Methods

Introduction . Creating a new herbal remedy with a mild generalized effect is an urgent task of modern pharmacology and pharmaceutical technology. The dosage form of an innovative medicinal product should take into account its properties, ensure the effectiveness of the drug and ease of intake. Aim . Creation of hard gelatin capsules with a plant composition-dry extract and validation of methods for quantifying the amount of flavonoids for the preparation of draft regulatory documentation. Materials and methods . The physicochemical and technological properties of the developed dry extract, as well as experimental capsule masses, such as mass loss during drying, bulk volume and granulometric composition, flowability, angle of natural slope, compaction, and parameters of the obtained capsules (solubility, disintegration, etc.) were studied according to the methods described in the State Pharmacopoeia of the XIV edition. Methods were developed for quantitative determination of flavonoid content in terms of rutin in dry extract and capsules using differential spectrophotometry, which were validated. Results and discussion . During the study of the experimental dry extract, its high hygroscopicity was found, which worsens its technological properties and complicates the encapsulation process. As a result of the addition of auxiliary substances, such as anhydrous lactose and talc, it was possible to obtain an optimal mass for encapsulation, which served as the basis for the creation of the drug «Sedoflav». Conclusion . On the basis of a dry extract of plant composition capsules «Sedoflavt» were developed, its standardization was produced. Methods for quantifying the amount of flavonoids in terms of rutin in experimental dry extract and capsules have been developed and validated.

Phytochemicals and Antioxidant Activities of Aloe Vera (Aloe Barbadensis)

Fresh Aloe vera leaves were collected from Itahari, Sunsari district Nepal and were well washed with distilled water and subjected to cabinet drying at 50°C until constant weight of sample was obtained. Thus, obtained dry powder was extracted using Soxhlet apparatus in two different solvents i.e. methanol and ethanol and further concentrated using rotatory vacuum evaporator that was used for Total Phenol Content (TPC), Total Flavonoid Content (TFC) and tannin content determination. The mean values of methanolic and ethanolic extract were then statistically analyzed at 5% level of significance by paired t-test. Fresh Aloe vera leaves were extracted in 96% methanol to determine chlorophyll-a, chlorophyll- b and total carotene content. Similarly, 99% methanol was used to determine Total Antioxidant Capacity (TOAC), DPPH radical scavenging activity and reducing power assay of fresh Aloe vera leaves. Keywords: Aloe-Vera; Total Phenol Content; Total Flavonoid Content; Total Tannin Content; Antioxidant Activity

In vitro antioxidant analysis and quantitative determination of phenolic and flavonoid contents of Emilia sonchifolia (L) D.C (Asteraceae) leaf extract and fractions

Emilia sonchifolia (L.) D.C. is a medicinal plant from the family Asteraceae known for a wide range of ethnomedicinal uses such as management of inflammatory diseases, pains, cancer, diabetes, cataract, asthma and liver disease. This research was aimed at assessing the antioxidant potential and quantitative determination of phenolic and flavonoid contents of the extract and fractions of Emilia sonchifolia leaves. The leaves of the plant were processed, extracted and partitioned successively and exhaustively with dichloromethane (DCM) and ethyl acetate. Phytochemical screening was carried out on the methanol extract using standard methods. Antioxidant evaluation of the methanol extract and fractions of Emilia sonchifolia leaves was carried out using Ferric Reducing Antioxidant Power (FRAP) assay and 2, 2, diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Quantitative determination of total phenolic content and total flavonoid content was done. The extraction and partitioning yielded the crude extract and respective fractions. The phytochemical screening revealed the presence of tannins, saponins, flavonoids, alkaloids and cardiac glycosides. Antioxidant evaluation of the crude extract and fractions of the plant exhibited significant (p<0.001) antioxidant activity in both assay though not comparable with the standard agent, ascorbic acid. In DPPH assay, the highest percentage inhibition was observed in ethyl acetate fraction (62%) followed by the extract (61%), DCM fraction (55%) and aqueous fractions (54%) at 100 µg/mL. In FRAP assay, the highest reducing power was exhibited by ethyl acetate fraction (0.457 nm) followed by the extract (0.444 nm), DCM fraction (0.441 nm) and aqueous fraction (0.439 nm). Although these activities were significant, they were not comparable to that of the standard drug ascorbic acid (0.914 nm). In total phenolic content assay ethyl acetate fraction had the highest phenolic content (5.804 mg/g), followed by crude extract (2.500 mg/g). The total flavonoid content was observed to be highest in ethyl acetate fraction (10.556 mg/g), followed by crude extract (4.444 mg/g). From this research work it was observed that Emilia sonchifolia leaves have a good antioxidant activity which could be responsible for its wide range of ethnomedicinal activities and this lends scientific credence for the use of this plant in the management of disease conditions.

In vitro antioxidant analysis and quantitative determination of phenolic and flavonoid contents of Emilia sonchifolia (L) D.C (Asteraceae) leaf extract and fractions

In vitro antioxidant analysis and quantitative determination of phenolic and flavonoid contents of Emilia sonchifolia (L) D.C (Asteraceae) leaf extract and fractions

Antimutagenic, antigenotoxic and antiproliferative activities of Fraxinus angustifolia Vahl. leaves and stem bark extracts and their phytochemical composition.

In recent years, chronic degenerative diseases such as certain types of cancers, are becoming an evident issue. DNA damage has been for long recognized as a causal factor for cancer development because mutations or chromosomal aberrations affect oncogenes and tumor suppressor genes leading cells to malignant transformation and to the subsequent cancerous growth. Medicinal plants are often used for the prevention or treatment of various diseases with great scientific interest. Among the medicinal plants distributed in the Mediterranean region, Fraxinus angustifolia Vahl. has been used in traditional medicine for its remarkable curative properties. However, in spite of this popularity, little works have been performed on the activity so that further studies should be performed to investigate in depth the antimutagenic, antigenotoxic and antiproliferative activities of the plant. Thus, the present study was aimed to the evaluation of the potential antimutagenic, antigenotoxic and antiproliferative properties of leaves and stem bark extracts of this well-known tree. Antimutagenic activity was evaluated by Salmonella mutagenicity assay in Salmonella typhimurium TA98 and TA100 strains. The antigenotoxic potential was assessed by umu test in the strain of S. typhimurium TA1535/pSK1002. Antiproliferative activity was studied on human hepatoblastoma (HepG-2) and on breast adenocarcinoma (MCF-7) cell lines by MTT assay. Furthermore, the antiproliferative activity observed on cancer cells was compared with that on the human normal-like fibroblasts (TelCOFS02MA) and the selectivity index was calculated to understand if extracts were able to exert selective toxicity towards cancer cells. Moreover, phenolic compounds are plant substances with a large spectrum of biochemical activities with antioxidant, antimutagenic and anticarcinogenic effects. Based on the strong evidence of biological activities of phenolic compounds, the study was focused on the determination of total phenolics and flavonoids contents, and the phytochemical composition of the extracts assessed by LC/MS. The ethanol extracts of both leaves and stem barks showed significant from moderate to strong antimutagenic and antigenotoxic effects. In addition, selective cytotoxicity towards cancer cells was shown by ethanolic leaves extract and aqueous/chloroform leaves and stem bark extracts. The latter showed high levels of total phenolic contents among all the other extracts. Identified phenylethanoids (calceolariosides, verbascoside) and secoiridoids (oleuropein and ligstroside) could be responsible for the demonstrated broad spectrum of healthy properties.

Determination of Flavonoid Contents and Evaluation of in vitro Antioxidant Activities of the Extract of Selected Citrus Fruit Peel

Flavonoids capture and neutralize the oxidative agents, and quench free radicals. The peel which represents almost one half of the fruit mass has been found to be the main sources of total phenols and flavonoids in the citrus fruit. In present study, flavonoid content and in vitro antioxidant activities of ethanol extracts from some selected citrus fruit peels grown in Ethiopia were determined. Colorimetric aluminum chloride was used for flavonoid content determination. In vitro antioxidant properties of the citrus fruit peels were determined by measuring DPPH and Nitric Oxide radical scavenging activity, and reducing power. The study result showed that lemon peel contained significantly the highest flavonoid content (8.88 ± 0.621 mg of quercetin equivalent/g of extract) at 100 µg/ml concentration. When compared to vitamin C used as standard, lemon peel extract showed significantly higher DPPH radical scavenging of 75.60 ± 2.4 %. Lime peel extract showed highest (0.38 ± 0.01) reducing power activity at 1000 µg/mL concentrations. Strong linear correlations was observed between flavonoid contents of selected citrus peel extract and DPPH free radical scavenging activity (r = 0.975, p = 0.025). Overall, in vitro antioxidant potential of citrus fruit peels extract grown in Ethiopia was confirmed and correlation between in vitro antioxidant activity and flavonoid content of citrus peel extract showed different trends. Further analysis is required to purify specific structure of flavonoid components of citrus fruit peel from Ethiopian cultivar using advanced purification techniques.