Antioxidant Activities Of Aerial Parts Research Articles

Wild Stinging Nettle (Urtica dioica L.) Leaves and Roots Chemical Composition and Phenols Extraction.

Stinging nettle (Urtica dioica L.) is an herbaceous plant that grows all over the world and is widely used as an edible and medicinal plant. Overall research results reveal that the chemical content and antioxidant activity of aerial parts and roots of stinging nettle depends on the growing region, soil, meteorological conditions (especially sunshine), collecting time, etc. The chemical composition of stinging nettle growing in Lithuania and the solid-liquid extraction efficiency of leaves and roots using different solvents were analysed. Additionally, we determined leaves phenols extraction efficiency using 96% methanol at different extraction conditions. Research results showed that a higher amount of crude fats, non-nitrogen extractives, and total carotenoids were in leaves, but the amount of crude proteins and ash did not differ significantly compared with roots. A higher amount of polyunsaturated fatty acids (PUFAs) and monounsaturated fatty acids (MUFAs) were detected in roots instead of leaves while saturated fatty acids (SFAs) were in leaves. The extraction results showed that the most effective solvent for total phenols and flavonoids in leaves was 96% methanol, for total phenols in roots was 50% methanol and 50% ethanol for total flavonoids in roots. The most effective temperature for the Urtica dioica L. leaves phenols extraction was 70 °C, while time does not have a significant influence. The present study's findings suggested that concentrated and binary solvents had different effects on the phenol's extraction efficiency from different stinging nettle parts and extraction temperature performed a key role instead of extraction time.

Antidiabetic, anticholinergic and antioxidant activities of aerial parts of shaggy bindweed (Convulvulus betonicifolia Miller subsp.) – profiling of phenolic compounds by LC-HRMS

In order to evaluate the antioxidant activity of evaporated ethanolic extract (EESB) and lyophilized water extract (WESB) of Shaggy bindweed (Convulvulus betonicifolia Mill. Subs), some putative antioxidant methods such as DPPH· scavenging activity, ABTS•+ scavenging effect, ferric ions (Fe3+) reduction method, cupric ions (Cu2+) reducing capacity, and ferrous ions (Fe2+) binding activities were separately performed. Also, ascorbic acid, α-tocopherol and BHT were used as the standard compounds. Additionally, some phenolic compounds that responsible for antioxidant abilities of EESB and WESB were screened by liquid chromatography-high resolution mass spectrometry (LC-HRMS). At the same concentration, EESB and WESB demonstrated effective antioxidant abilities when compared to standards. In addition, EESB demonstrated IC50 values of 1.946 μg/mL against acetylcholinesterase (AChE), 0.815 μg/mL against α-glycosidase and 0.675 μg/mL against α-amylase enzymes.

Effects of silicon on some phytochemical traits of purple coneflower (Echinacea purpurea L.) under salinity

ABSTRACT Silicon is the second most abundant element present in the earth's crust following the oxygen. Although it is not considered as an essential element for plant growth, some studies have suggested that silicon application significantly increases plant growth under salinity conditions. In order to investigate the effect of salinity stress and silicon on some phytochemical traits of purple coneflower (Echinacea purpurea L.), a pot experiment was conducted in a factorial-based completely randomized design with four salinity levels and four silicon concentrations with four replications. The measured traits include antioxidant activity of aerial parts, root and shoot proline, total flavonoid and phenol in shoot, caffeic acid concentration in aerial parts and root, and chlorogenic acids in root and shoot. The results showed that the interaction of salinity and silicon was significant for all traits except for the antioxidant activity of the shoot. Salinity stress significantly affected the chlorogenic acid content of the root. The effect of salinity on the caffeic acid content of root was significant at 1%, however, it did not affect the amount of caffeic acid in the shoot. The interaction of salinity and silicon on caffeic acid content of root was significant at 5% suggesting that silicon can reduce the negative effects of salt stress on the purple coneflower.

Antioxidant Activity of Decoction and Infusion of Teucrium chamaedrys subsp. chamaedrys Grown in Turkey

In this study, antioxidant activity of aerial parts of Teucrium chamaedrys subsp. chamaedrys decoction and infusion were studied. The antioxidant activities were analyzed based 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, β-carotene linoleic acid assays, and cupric (Cu2+) ion reducing power assay (CUPRAC). Infusion and decoction extracts at the concentration of 100 µg/mL, demonstrated higher antioxidant activity (86.5% and 84.1%, recpectively) than synthetic antioxidants (81.1%, BHA and 78.8%, BHT) in DPPH scavenging assay. Our results indicate that T. chamaedrys subsp. chamaedrys tea can be a promising source of natural antioxidant agent.

Effect of Geographical and Seasonal Variations on Phenolic Contents and Antioxidant Activity of Aerial Parts of Urtica diocia L.

Background: Environmental conditions affect the biosynthesis of secondary metabolites as a result of biotic and abiotic factors. In the present study, the effect of different geographical locations and season was studied on total phenolic and flavonoid contents extracted from Urtica dioica Linn. Methodology: The aerial parts of U. dioica collected from Palampur, Shimla and Dharamshala in different seasons were subjected to hydro-alcoholic extraction. Quantitative estimation of total phenolic and flavonoid contents in various extracts was carried out spectrophotometrically. Results: The highest amount of total phenolic (3.987± 0.130) and flavonoid contents (2.847± 0.341) was found in Palampur sample collected in summer season whereas sample collected from Dharamshala in spring season showed the least phenolic contents. In vitro antioxidant activity of all the samples was evaluated by DPPH, NO scavenging and FRPA method. The antioxidant potential was found maximum in the sample collected from Palampur in the summer season, however, the sample collected from Dharamshala in spring season showed the least antioxidant potential. Conclusion: The present study confirms that altitude and seasonal variations significantly affect the levels of secondary metabolites in plant parts.

Hepatoprotective and antioxidant activity of aerial parts of Moringa oleifera in prevention of non-alcoholic fatty liver disease in Wistar rats

Non-alcoholic fatty liver disease (NAFLD) has a high incidence in Iran. In this study, identification of three antioxidants including caffeic acid, quercetin and gallic acid in leaf and stem extracts of Moringa oleifera(MO) was performed by high performance liquid chromatography (HPLC). The antioxidant properties of methanolic extracts were considered using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The effect of aerial parts of MO on NAFLD was investigated. For this, 30 adult male Wistar rats with an average weight of 185 ± 10 g were divided in to 6 groups and fed with high-fat diet (HFD) including 24 g of Corn Oil per 100 g diet (to induce fatty liver) and then treated with 2% and 4% of leaf and stem powder of MO for 8 weeks. One group was fed on the basal diet as control group. At the end, the blood tests were performed and histological changes were examined. The levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. Treatment of rats with MO led to significant reduction (p < .05) in TC, TG, LDL, VLDL, ALT and AST compared to the HFD group. On the contrary, increased levels of HDL-C. Histopathological examinations demonstrated steatosis and inflammatory in HFD group liver sections. Significant decreases (p < .05) were observed in steatosis and inflammatory in groups treated with MO compared to the HFD group. This study suggests that aerial part of MO is a potential source of compounds with antioxidant activity, hence it can prevent NAFLD.

Polyphenolic contents and antioxidant activities of aerial parts of Salvia multicaulis from the Iran flora

Folk medicine sometimes involves the use of salvia species for therapeutic purposes. Polyphenols with the highest amounts included rosmarinic acid (7.358mg/g), catechin (1.5 mg/g), vanillin (1.00 mg/g), chlorogenic acid (0.53 mg/g), quercetin (0.16 mg/g), and p-coumaric acid (0.015). Furthermore, the results showed that S. multicaulis has a high content of total phenol (4.39 mg/g) and DPPH activity (8.44 mg/g). Salvia multicaulis could be potentially used as a medicinal plant because of its antioxidant activity and polyphenol content.

Antioxidant Activity and Cardioprotective Effect of Potentilla reptans L. via Ischemic Preconditioning (IPC)

Background and objectives Potentilla reptans L. from Rosaceae family is used as traditional medicine in Iran and other countries. Previous investigations on Potentilla species have reported strong antioxidant activity and cardioprotective effect. In this study, antioxidant activity of aerial parts and root of Potentilla reptans, and the cardio protective role of its root on preconditioning ischemia reperfusion injury have been investigated.MethodsAntioxidant activity of aerial parts and root of this plant were measured by DPPH and FRAP methods and its total phenolics content was estimated by Folin-Ciocalteu assay. Catechin was isolated from ethyl acetate fraction by Paper chromatography. Cardioprotective role of P. reptans root were evaluated by thirty five rats in five groups.The hearts were subjected to 30 minutes of ischemia and 100 minutes of reperfusion. The ischemic preconditioning (IPC) protocol was applied before the main ischemia. The myocardial infarct size was estimated by triphenyltetrazolium chloride (TTC) staining. The hemodynamic parameters, arrhythmia scoring and coronary flow were measured during reperfusion.ResultsPotentilla reptans root showed stronger antioxidant activity and total phenolics content compared to the aerial parts. Total extract of root significantly decreased the infarct size and increased coronary flow in a concentration-dependent manner.ConclusionOur results showed that the protective effects of Potentilla reptans root appeared by its phenolic compounds and reactive oxygen species (ROS) inhibition mechanism.

Sex-related differences in essential oil composition, phenol contents and antioxidant activity of aerial parts in Pistacia lentiscus L. during seasons

Essential oil composition, total phenolic, flavonoid and condensed tannin contents were assessed in different aerial parts of the same females and males of Pistacia lentiscus over four harvesting times. Marked quantitative and qualitative in terpenic and phenolic composition depending on sex, plant part and collecting periods were observed. At the species level, the main major compounds of essential oils in the leaves and stems were α-limonene, α-pinene, germacrene-D and β-myrcene with female plant stems being rich in these compounds. Male flowers produced highest amounts of α-terpinen-4-ol and β-caryophyllene, whereas, fruits accumulate the highest level of β-myrcene. α-limonene and germacrene-D reached their highest contents at fruiting in females and at flowering in males. The highest total phenolic, flavonoid and condensed tannin contents were higher in male leaves and flowers, with marked decreasing of contents from the vegetative to the ripening period. The antioxidant activity of acetonic extracts assessed by the DPPH and FRAP assays differs significantly among aerial plant parts. The lowest averages of IC50 were observed in leaves at the vegetative and the flowering stages, respectively. The ferric reducing antioxidant ability (FRAP) for leaves and stems differs between sexes and organs with male extracts taken during the vegetative and flowering stages being more active. The revealed differences in chemicals and antioxidant activities among genders, organs and phenological stages should help to the optimization of P. lentiscus use in industrial and pharmaceutical fields according to the variation of its chemical composition.

Chemical Study and Evaluation of Anti-Inflammatory, Antitumor and Antioxidant Activities of Aerial Parts from Aeschynomene sensitiva

A especie Aeschynomene sensitiva e considerada uma erva daninha que ocorre principalmente em regioes de clima tropical alagavel, e pode ser encontrada em varios estados brasileiros. Ate o presente momento nao ha relatos na literatura sobre estudo quimico e farmacologico para essa especie. O primeiro estudo fitoquimico de sementes, folhas e galhos de Aeschynomene sensitiva levou ao isolamento do rotenoide glicosilado 6’-hidroxi-6a, 12a-dehidrorotenone, do isoflavonoide glicosilado 2’,7 dihidroxi-4’,5’dimetoxiisoflavona, dos flavonoides quercetina 3-O-β-D-glicosideo, quercetina 3-O-β-D-galactopiranosideo e quercetina-3-O-α-L-ramnopiranosideo, dos compostos fenolicos acido galico e galato de metila e da saponina soiasaponina I.. As estruturas dos compostos isolados foram atribuidas com base em dados espectroscopicos de RMN uni- e bidimensionais e comparacao com dados da literatura. Foram avaliadas as atividades anti-inflamatoria, antitumoral e antioxidantes do extrato metanolico bruto e suas fracoes. As fracoes acetato de etila das sementes (FAcS) e folhas (FAcF) apresentaram elevada atividade antioxidante com IC50 12,4 and 18,2 µg/mL, respectivamente.

Measurement of total phenolic content and antioxidant activity of aerial parts of medicinal plant Coronopus didymus.

To evaluate the total phenolic content and compare the antioxidant activity of various solvent extracts and fractions from the aerial parts of Coronopus didymus through various assays. Total phenolic content was determined using the Folin-Ciocalteu assay and the invitro antioxidant activity of a number of different extracts was investigated in a dose-dependent manner with three different methods: the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and ferric reducing antioxidant power (FRAP) assays. A flavone was isolated from the most active ethanolic extract with high antioxidant activity using size exclusion chromatography. IC50 values were calculated for the DPPH and ABTS methods. The FRAP activity was assessed in terms of μM Fe (II) equivalent. The phenolic content was found to be highest in the ethanol extract (CDA Et; 47.8mM GAE) and the lowest in the dichloromethane extract (CDA DCM; 3.13mM GAE). The ethanol extract showed high radical scavenging activity towards DPPH and ABTS radicals with IC50 values of (7.80×102) and (4.32×102) μg/mL, respectively. The most active ethanol extract had a FRAP value of 1921.7μM Fe (II) equivalent. The isolated flavone F10C (5,7,4'-trihydroxy-3'-methoxy flavone) was far more effective for scavenging free radicals in the DPPH and ABTS assays with IC50 of 43.8 and 0.08μg/mL, than the standard trolox, with IC50 values of 97.5 and 21.1μg/mL, respectively. In addition, the flavone F10C and the standard ascorbic acid had FRAP values of 1621.7 and 16038.0μM Fe (II) equivalents, respectively. The total phenolic content of extracts in decreasing order is ethanol extract (CDA Et)>acetone extract (CDA ACE)>phenolic extract (CDA MW)>n-hexane extract (CDA nHX)> chloroform extract (CDA CHL)>dichloromethane extract (CDA DCM). The ordering of extracts in terms of antioxidant activity from highest to lowest is CDA Et>CDA MW>CDA DCM>CDA CHL>CDA ACE>CDA nHX in DPPH, ABTS and FRAP assays. A significant relationship is found between antioxidant potential and total phenolic content, suggesting that phenolic compounds are the major contributors to the antioxidant activity of C. didymus.

Chemical composition and antioxidant activity of aerial parts of Ferula longipes Coss. ex Bonnier and Maury

This is the first study on the phytochemistry and antioxidant activity of Ferula longipes Coss. ex Bonnier and Maury (Apiaceae). A new flavonoid quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-[2-O-caffeoyl]-glucopyranoside (1), along with 10 known compounds kaempferol-3-O-α-L-rhamnopyranoside (2), quercetin-3-O-α-L-rhamnopyranoside (3), kaempferol-3-O-ß-D-glucopyranoside-7-O-α-L-rhamnopyranoside (4), isorhamnetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (5), quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (6), isorhamnetin-3,7-di-O-β-D-glucopyranoside (7), apigenin (8), apigenin-7-O-ß-D-glucopyranoside (9), 3,5-dicaffeoylquinic acid (10), deltoin (11) were isolated from the aerial parts of Ferula longipes Coss. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. The compounds 1, 3, 4, 6, 7 and 10 were evaluated for their antioxidant activity, compound 1 exhibited the best antiradical activity potential and showed IC50 and A0.5 values 5.70, 7.25, 5.00, and 2.63 μg/mL towards DPPH free radical-scavenging, ABTS, CUPRAC, and reducing power assays, respectively compared with BHA, BHT and ascorbic acid which were used as positive controls.

Screening Antianxiety and Antioxidant Profile of Stems and Leaves of Blue Variety of Clitoria ternatea L

Previous studies from our laboratory demonstrated that the antianxiety and antioxidant activities of the roots of the blue variety of Clitoria ternatea were greater compared to the white variety. An attempt has been made to investigate the antianxiety and antioxidant activities of aerial parts of this plant using elevated plus maze and 2,2-diphenyl-1-picrylhydrazyl assay, respectively. Methanol extract of stems and leaves of the blue variety (50, 100 or 200 mg/kg, p.o.), diazepam (2 mg/kg, p.o.) and control (vehicle) were separately evaluated for antianxiety activity. The stem extract (200 mg/kg) and leaf extract (100 or 200 mg/kg) exhibited significant antianxiety activity with respect to control and standard. The remaining doses did not exhibit any antianxiety activity. Mice treated with the blue variety leaf extract, showed decresed number of entries from 6.20 to 4.60 when the dose was increased from 100 to 200 mg/kg indicating a possibility of decreased locomotor activity, which could be due to cental nervous system depressant activity. In case of blue variety stem extract, the average number of entries increased from 3.20 to 5.80 as the dose was increased from 100 to 200 mg/kg. The IC50 values of ascorbic acid, blue variety stem extract and leaf extract were found to be 20.01, 264.32 and 251.13 µg/ml, respectively. None of the plant parts showed activity close to that of ascorbic acid. Finally, it can be concluded that aerial parts of blue variety of C. ternatea exhibited mild antianxiety and antioxidant activities.

English

The chemical compositions of the essential oil of Asperula oppositifolia aerial parts were examined by gas chromatography/mass spectrometry (GC/MS); forty-two compounds were identified. Analysis of this essential oil revealed the presence of 2-(6,6-Dimethyl bicyclo[3.1.1]hepta-2en-2-yl) ethanol (17.16%), Decane (8.47%) , Dibuthyl phthalate (5.59%) and 1-Bromo Naphthalene(4%). The antioxidant activity of aerial parts of methanolic extract was studied by in vitro 2&rsquo;2&rsquo;-diphenylpicrylhydrazyl (DPPH) radical &ndash; scavenging activity, revealing that this plant could be used as new medicinal resource for antioxidant agent. Key words: Chemical composition, essential oil, 2-(6,6-Dimethyl bicyclo[3.1.1]hepta-2en-2-yl)ethanol, Asperula oppositifolia ,antioxidant activity.

서양민들레(Taraxacum officinale) 지상부, 지하부 및 혼합 추출물의 항산화 활성 비교

The present investigation evaluated the antioxidant activities of water extracts from dandelion (Taraxacum officinale) aerial parts, roots, and mixed extracts. Mixed extract of T. officinale was a mixture of aerial parts and roots at 9:1 and 8:2 weight ratios. Extracts from aerial parts (DAE), roots (DRE), and mixture of aerial parts and roots (DME) were measured for cell viability and catalase activity in HepG2 cells, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and lipid peroxidation inhibitory activity. Cell viabilities of HepG2 cells treated with DAE, DRE, DME 8:2, and DME 9:1 against H2O2-induced oxidative damage were 63.4%, 54.6%, 76.7% and 83.4% at a concentration of 400 μg/mL, respectively. Catalase activity was highest in DME 9:1 (12.2 mU/min/mg protein) compared with DAE (9.0 mU/min/mg protein) and DRE (9.7 mU/min/mg protein). DPPH radical scavenging activity of DME showed a significantly lower EC 50 value than DAE (EC 50 value of DME 9:1=163.3 μg/mL, DME 8:2=172.4 μg/mL, and DAE=173.7 μg/mL). Lipid peroxidation inhibitory activity of DME showed a significantly lower EC 50 value than DAE [EC 50 values of DME (9:1)=454.4 μg/mL, DME (8:2)=426.6 μg/mL, and DAE=654.7 μg/mL]. The results indicate that a small amount of T. officinale roots increased antioxidant activity of aerial parts. Especially, a 9:1 mixture was more valuable than 8:2 mixture for industry.

Antioxidant properties of Helichrysum pseudoplicatum Nab

The genus Helichrysum (Asteraceae) is comprised of approximately 500-600 species and used for the treatment of a variety of pathological conditions in folk medicine in many countries. In this study, antioxidant activities of aerial parts of H. pseudoplicatum were investigated employing various in vitro assay systems, i.e. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide radical scavenging, reducing power and hydrogen peroxide scavenging. IC50 for DPPH radical-scavenging activity was 438.9 ± 15.6 µg ml -1 . The extract exhibited good reducing power at 25 - 400 µg ml -1 but was not comparable with that of vitamin C. The extract showed good nitric oxide-scavenging activity. IC50 was 474.3 ± 11.8 µg ml -1 . It was capable of scavenging hydrogen peroxide in a concentration dependent manner. It showed good activity. Its IC50 was 159.8 ± 8.2 µg ml -1 . The IC50 values for ascorbic acid and BHA were 21.4 and 52.0 µg ml -1 , respectively. The total amount of phenolic compounds in the extract was determined as gallic acid equivalents (22.7 ± 3.1 mg /g of extract) and total flavonoid contents were calculated as quercetin equivalents (9.6 ± 1.3 mg /g of extract) from a calibration curve. This plant contained low amount of total flavonoids and phenolic compounds. Its moderate antioxidant activities may be attributed to its low levels of phenols and flavonoids.

Effects of drying on caffeoylquinic acid derivative content and antioxidant capacity of sweet potato leaves

Caffeoylquinic acid (CQA) derivatives are known to possess antioxidative potential and have many beneficial effects on human health. The present study compared the CQA contents and antioxidant activities of aerial parts of sweet potato plants. The effects of drying methods (freeze drying, and drying at 30°C, 70°C, and 100°C) on these two parameters of the first fully expanded leaves were also assessed. The results indicated that the CQA derivatives were detectable in leaves, stem, and flowers of sweet potato plants (varied from 39.34 mg/g dry weight to 154.05 mg/g dry weight), with the leaves (particularly expanding and first fully expanded leaves) containing more CQA derivatives than other aerial plant parts. The expanding and first fully expanded leaves also exhibited greater antioxidant activities than other aerial plant parts, possibly due to their higher contents of CQA derivatives. Drying method significantly affected the content of CQA derivatives in dried sweet potato leaf tissues. Drying treatments at both 70°C and 100°C significantly reduced the CQA derivative content and antioxidant activity in the first fully expanded leaves. Among the tested drying methods, the freeze-drying method demonstrated the preservation of the highest amount of CQA derivatives (147.84 mg/g) and antioxidant property. However, 30°C cool air drying was also a desirable choice (total CQA derivative content was reduced to only 129.52 mg/g), compared to 70°C and 100°C hot air drying, for commercial-scale processing of sweet potato leaves, if the higher operation cost of freeze drying was a major concern.

Biological and pharmacological effects of Delphinium elbursense

Antidepressant, antihypoxic and antioxidant activities of aerial parts of Delphinium elbursense were investigated employing nine various assay systems. Antidepessant activity was examined by using forced swimming test and tail suspension test in mice. The extracts at all tested doses show significant activity as compared to control group. Antihypoxic activity was investigated in two models, haemic and circulatory. The effects were pronounced and dose-dependent in both model of hypoxia. Extracts showed weak antioxidant activity in some models. IC50 for 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical-scavenging activity was 116.2 ± 5.6 mg ml -1 . Extracts showed nitric oxide-scavenging activity between 0.1 and 1.6 mg ml -1 (IC 50 = 502.3 ± 18 mg ml -1 ) and a very weak Fe 2+ chelating ability (IC 50 = 1.01 ± 0.03 mg ml -1 ). It also exhibited low antioxidant activity in hemoglobin-induced peroxidation of linoleic acid but was capable of scavenging hydrogen peroxide in a concentration dependent manner. Extract show antihemolytic activity againts hydrogen peroxide (H 2 O 2 ) induced hemolysis (558.7 ± 31 mg ml -1 ). The total phenolic compounds in extract were determined as gallic acid equivalents (52.24 ± 1.7) and total flavonoid contents were calculated as quercetin equivalents (17.26 ± 0.6) from a calibration curve. Keywords: Antidepressant, antihypoxic, Delphinium elbursense , flavonoid contents, forced swimming test, medicinal plants, phenolic contents, tail suspension test African Journal of Biotechnology Vol. 9(34), pp. 5542-5549, 23 August, 2010

Effects of Extraction Methods on Phenolic Contents and Antioxidant Activity in Aerial Parts of Potentilla atrosanguinea Lodd. and Quantification of Its Phenolic Constituents by RP-HPLC

The effects of different solvent systems (methanol, ethanol, acetone, and their 50% aqueous concentrations) and extraction procedures (microwave, ultrasound, Soxhlet and maceration) on the antioxidant activity of aerial parts of Potentilla atrosanguinea were investigated by three different bioassays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays and ferric reducing antioxidant potential (FRAP). The 50% aqueous ethanol extracts exhibited strong antioxidant activity measured in terms of Trolox equivalent antioxidant capacity (TEAC) [(54.34 to 122.96, 29.82 to 101.22 and 13.64 to 41.43) mg of Trolox/g] with ABTS (*+), DPPH (*) and FRAP assays, respectively. In general, TEAC of Soxhlet extracts was found to be 1.8 and 3 times higher than ultrasound and maceration but slightly (1.2 times) higher than microwave. A positive correlation (r(2) = 0.931 to 0.982) was observed between total polyphenol (TPC) and total flavonoid (TFC) contents which ranged between 26.7 to 30.7 mg/g gallic acid equivalent and 16.8 to 20.8 mg/g quercetin equivalent respectively, with antioxidant activity. In addition, some of its bioactive phenolic constituents which contribute largely toward antioxidant potential such as chlorogenic acid, catechin, caffeic acid, p-coumaric acid and quercetin were also quantified in different extracts by RP-HPLC.

Essential oil composition and antioxidant activity of aerial parts of Grindelia robusta from Central Italy

The chemical composition of the essential oil obtained from Grindelia robusta aerial parts from central Italy was analyzed by GC and GC/MS and 45 components were identified. Borneol (15.2%), α pinene (10.3%), trans-pinocarveol (7.0%), bornyl acetate (4.5%), limonene (4.3%) were the main components. The antioxidant activity of the essential oil was evaluated using the DPPH and 5-lipoxygenase tests.