Antioxidant Activity Of Alcoholic Extracts Research Articles

Antioxidant Activity and Volatile Oil Analysis of Ethanol Extract of Phoebe zhennan S. Lee et F. N. Wei Leaves

The medicinal value of P. zhennan has been documented in traditional Chinese medicine books. The aim of this paper was to study the antioxidant activity of alcoholic extracts of P. zhennan leavesusing 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-phenyl-4,4,5,5-tetramethylimidazolineoxyl-1-oxyl-3-oxide (PTIO) radical scavenging and ferric ion reducing antioxidant power (FRAP) assays. The active components of the leaves were identified via headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPME-GC-MS). The results showed that the scavenging rate of DPPH was 94.67%with an EC50 value of 0.674 mg/mL at a concentration of 2 mg/mL. The maximum scavenging rate was 47.40% at a Trolox equivalent of 0.33 mg TE/mL for PTIO radicals. The FRAP reached 84.80% at 0.20 mg/mL concentration. The results confirmed the strong antioxidant activity of the extracts. Furthermore, 44 compounds, mostly terpenoids, obtained from the alcoholic extracts of P. zhennan leaves were analyzed using HS-SPME-GC-MS and 15 of these compounds had a relative content exceeding 1%. The strong antioxidant activity of the alcoholic extracts of P. zhennan leaves could be attributed to the presence of copaene (33.97%), β-caryophyllene (4.42%), δ-cadinene (11.04%), γ-muurolene (4.78%), cis-calamenene (2.02%), linalool (1.04%), α-pinene (1.46%), borneol acetate (1.5%), and γ-terpinene (0.66%). This study demonstrates the potential medicinal value of alcoholic extracts of P. zhennan leaves.

Antioxidant Study of Coffea Cruda

Background: Coffea cruda (family Rubiaceae) has great therapeutic significance in Indian system of medicine due to its rich antioxidant activity. Coffea cruda is the major source of antioxidant compounds as it has strong ability to inhibit the process of oxidation in the body which attributes to its high antioxidant activity. The main objective of the present work was to evaluate antioxidant study of Coffea cruda alcoholic extract. Objectives:The present study was designed to investigate the HPTLC study and anti-oxidant activity of of Coffea cruda alcoholic extract. Materials and methods: Anti-oxidant activity of alcoholic extract of Coffea cruda was determined by DPPH free radical scavenging activity, Total phenol, Total flavonoid content, ABTS and FRAP assay methods. Whereas, HPTLC study performed on precoated silica gel 60 F254 TLC plate where, mobile phase used was toluene: acetone (7:3, v/v). HPTLC UV detection was performed at 254 nm. Results:The result revealed that different antioxidant assays of alcoholic extract of Coffea cruda seed shows prominent antioxidant activity and High performance thin layer chromatography study indicates the presence of alkaloid compound caffeine in chloroform extract of Coffea cruda. Conclusion:The present study justifies Coffea cruda medicinal usage in traditional medicines. High antioxidant potentials are the reason for its cure and healing properties.

Phytochemical composition and antioxidant activity of three medicinal plants from southeastern Kazakhstan

Main results on study of phytochemical composition and antioxidant activity of three plants growing in southeastern part of Kazakhstan, namely A. schrenkiana, L. turkestanicus and C. tianschanica. Plant material was collected on flowering stage in July 2020. This study was carried out to evaluate the phytochemical constituents and antioxidant potential in order to validate the medicinal potential of these herbs. The antioxidant activity of alcoholic extracts was evaluated using 2,2 diphenyl-l-picrylhydrazyl (DPPH) assays. The total polyphenol and flavonoid content were determined according respectively to Spanos-Wrolstad and Zhishen method. The essential oil composition of samples was analyzed by gas chromatography (GC) (Agilent 7890A) coupled by flame ionization detector and mass spectrometry (Agilent 5975C) using capillary column (HP Innowax Capillary; 60.0 m×0.25 mm×0.25 µm). Phenols in A. schrenkiana (2.83 mg OE/g), in L. turkestanicus (2.86 mg OE/g), in C. tianschanica (16.08 mg OE/g). Flavonoids in C. tianschanica (21.79 mg RE/g), in L. turkestanicus (4.29 mg RE/g), in A. schrenkiana (3.8 mg RE/g). C. tianschanica (IC50 = 0.78 µg.mL) had greater antioxidant activity than A. schrenkiana (IC50 = 3.7 µg.mL) and L. turkestanicus (IC50 = 3.38 µg.mL). The components of the essential oil of A. schrenkiana revealed 13 types of chemical elements, of which the indicators of camphor (44.79%) and 1.8-cineole (29.05%) were high.

Comparison of antioxidant activity of extracts of hop leaves harvested in different years

Summary Introduction: Hop (Humulus lupulus L.) is a common plant in Europe, with many beneficial health effects. In addition to the use in brewing, hops are a valuable source of active substances used in conventional and folk medicine, such as humulones and lupulones, as well as antioxidants, including phenolic compounds. Objective: The aim of the study was to evaluate and compare the antioxidant activity of alcoholic extracts of fresh hop leaves collected in 2017 and 2018. Material and methods: The raw material consisting of fresh hop leaves was extracted using ultrasound-assisted extraction. Methyl, ethyl and isopropyl alcohol at three concentrations were used as extractants. The antioxidant activity of extracts was determined using DPPH and FRAP methods. Total phenolic content was evaluated using the Folin-Ciocalteu technique. Results: All the extracts showed antioxidant potential as well as the phenolic content. Regardless of the harvesting year and methods of evaluation, the highest antioxidant activity and the total polyphenol content were observed for extracts prepared in undiluted methanol, obtained during one hour lasting extraction. Conclusion: The results of the studies have suggested that hop leaves can be a potential source of health-promoting antioxidants.

BIOCHEMICAL CHARACTERISTIC AND ELEMENTC COMPOSITION OF <i>CICHORIUM INTYBUS</i>, KONUS CULTIVAR

Chicory is widely cultivated in many countries of the world due to high nutritional and pharmacological value. The possibility of chicory forcing in winter provides quick production of salad heads, which biochemical characteristics are not fully described. Concentration of sugars, water soluble compounds and antioxidants in roots, leaves and stumps of salad C.intybus Konus cv are studied. Element composition of roots and leaves is obtained using ICP-MS method. The highest amount of water soluble compounds and ascorbic acid was indicated in stumps, while the highest polyphenol concentration was demonstrated in leaves. Antioxidant activity of alcoholic extracts reached maximum in leaves and did not differ between roots and stumps. The ability of Konus variety to hyperaccumulate selenium was revealed for the first time: selenium concentration reached 2800 mcg/kg d.w. in roots and 3800 mcg/kg d.w. in leaves. Konus cv was characterized also by high accumulation of chromium, manganese, molybdenum and iron. Uneven distribution of elements between roots and leaves are demonstrated for all elements except Al, As and Si. Intensive root-leaves transport was revealed for Ca, Cr, Cu, Fe, K, Mg, Mn, Mo, Ni, P, Pb, Se and Zn and decreased rootleaves flow for B, Cd, Co, Li, Sn, Sr, V and especially Na. One hundred g of fresh leaves provides 22% of the daily adequate consumption levels for Se, 91%- for Cr, 15%- for Mo, 14%- for Fe and 12 % for Mn. The results suppose high prospects of C.intybus Konus cv as a functional food, capable to optimize the human Se and Cr status.

Differences Between Aronia Medik. Taxa on the Morphological and Biochemical Characters

Useful wild plants usually decrease the content of biologically active substances in the culture. However, no one studied the reverse process and didn’t know whether the level of biologically active compounds increases in plants escaping from culture and becoming invaded in natural communities (invasive species). We studied Aronia melanocarpa, A. arbutifolia and A. × prunifolia in the arboretum of the Main Botanical Garden (Moscow, Russia), which were brought from the USA in the 1980s. Two samples of cultivated A. mitschurinii and one sample of invasive A. mitschurinii from the Moscow region were also included in the analysis. The task of the study is to determine the degree of heritability of macro- and micromorphological characters of North American plants introduced to Europe and their comparison with the analogous parameters of mane-made A. mitschurinii, especially with naturalized plants. The identification of the samples most promising for further broad cultivation by their antioxidant activity and the content of microelements in leaves was also our research purpose. The digital microscope KeyenceVHX-1000 and scanning electron microscope LEO 1430 VP were used for examining leaves by the trichome density and stoma’s parameters. The antioxidant activity of the fruits was determined by the 2,2-difenyl-1-picrylhydrazyl (DPPH) free radical scavenging test. The content of microelements in the plant material was determined by using ICP-MS (Agilent 7700ce, USA). The diagnostic features of the introduced North American Aronia were found to be inherited under culture conditions. The mass of fruits increases in this order: A. arbutifolia → naturalized A. mitschurinii →A. × prunifolia → A. melanocarpa → cultivated A. mitschurinii. An original table has been compiled to compare the studied taxa on 21 biomorphological features. The total antioxidant activity in dry fruits for methanol, ethanol and for water extracts was determined. Naturalizing plants have a higher antioxidant activity of alcohol extracts than cultivated plants, and, on the contrary, lower antioxidant activity of water extracts. There are 17 microelements (ppm) in the leaves of Aronia taxa. A. mitschurinii have the highest content of 10 from them: Fe, Mn, Sr, Zn, Se, Cu, Mo, Cr, As and Sb; A. × prunifolia have the highest content of 6 ones: Ni, Co, V, Cd, Pb, Sn; and A. arbutifolia have the highest content of B. Our observations suggest that naturalizing plants of Aronia have a potential source of useful bioactive compounds. Apparently, plants in a comfortable culture environment accumulate fewer biologically active substances than during forced adaptation to unfavorable ecological conditions. DOI: http://dx.doi.org/10.5755/j01.erem.74.4.20893

COMPARATIVE EVALUATION OF ANTIOXIDANT ACTIVITY IN SEVERAL PERENNIAL ONION

Evaluation of biochemical characteristics of 8 perennial Allium species is achieved (A. ramosum, A. caeruleum, A. erubescens, A. obliquum, A. moly, A. aflatunense, A. oreophilum and A.ursinum). High nutritional significance of separate decorative species is demonstrated. A. caeruleum is shown to be a leader in the accumulation of ascorbic acid (more than 9000 mg/100 g d.w.) and polyphenols (more than 8000 mg GAE/kg d.v.). Detected ascorbic acid concentration range for 8 studies Allium species was 568 (A. ramosum) – 9980 (A. caerulum) mg/100 g d.w.; polyphenols 1392 (A. obliquum) – 8582 (A. caerulum) mg GAE/kg d.w.; water-soluble compounds 28 (A. aflatunense, A. obliguum) – 69 (A. ramosum) mg/kg d.w.; chlorophyll 0.54 (A.oreophilum) – 1.69 (A. ursinum) mg/100 g d.w.; carotene 0.07 (A. oreophilum) – 0.25 (A.ursinum) mg/100 g d.w.; selenium 72 (A. ursinum) – 245 μg/kg d.w., (A. ramosum). Adequate consumption level of vitamin C may be provides by 6.2 g of A.caerulum leaves. Antioxidant activity of Allium species alcoholic extracts composed a range from 1.5 (A. obliquum) to 6.4 (A. ursinum) mg GAE/g d.w. A. ramosum and A. oreophilum demonstrated the highest content of total soluble solids. The highest content of photosynthetic pigments happened to be typical for A. ursinum. The ratio between antioxidant activity of alcoholic and water extracts of Allium leaves was in the range between 0.89 and 2.21 depending on plant species: the highest value was registered in leaves of A. ursinum, the lowest – in leaves of A. ramosum. In a whole the highest content of antioxidants was demonstrated for leaves of A. caerulum. The highest levels of photosynthetic pigments and antioxidant activity of alcoholic extracts were indicated in leaves of A. ursinum.

Comparative Antioxidant Activity and Volatile Oil Composition of Leaves and Fruits of Thuja orientalis Growing in Egypt

Thuja orientalis L. (Cupressaceae) is an evergreen arbor that is distributed throughout Northeast Asia as a common ornamental plant. The volatile oil of leaves and fruits of T. orientalis growing in Egypt was prepared by hydro-distillation followed by GC-MS analysis in order to compare between their compositions. Results revealed that fruits are richer in monoterpenes (62.5 %) while leaves are richer in sesquiterpenes (57 %). The major components in leaf oil are; α-cedrol (15.8 %), β-caryophyllene (15 %), α-humulene (10.7 %), d-limonene (7.3 %), α-pinene (6.9 %), β-myrecene (5.9 %) and α-terpinolene (5.2 %). On the other hand, fruit oil contains α-pinene (11.3 %), α-cedrol (11.2 %), β-myrecene (9.6 %), geranyl acetate (9 %) and β-caryophyllene (8.9 %) in major amounts. Comparison between the oil content in the Egyptian conifer and other reported conifers worldwide is also discussed. Comparative determination of total phenolic content (TPC), total flavonoids content (TFC) and anti-oxidant activity of alcoholic extract of both leaves and fruits showed that fruits content of flavonoids (0.6267±0.026 mg RE /g) is double the content of the leaves (0.3069±0.019 mg RE /g). Similarly, fruits contain higher phenolic content (0.75±0.007 mg GE/g) compared to 0.51±0.007 mg GE/g in leaves. Also, fruits extract exhibited higher anti-oxidant activity (2.3516±0.0 mg AEAC/g) than leaves (1.2734±0.0022 mg AEAC/g). The extracts of T. orientalis could be a valuable material for pharmaceutical industry.

Antioxidant Activity and Infrared Spectroscopy Analysis of Alcoholic Extracts Obtained from Paecilomyces hepiali (Ascomycetes).

This research studies the influence of substrate on the antioxidant activity of alcohol extracts of Paecilomyces hepiali. We used corn, rice, millet, and peas as substrates. Antioxidant activity was measured with the DPPH radical scavenging method. Concentrations of extracts (6.25, 3.12, 1.56, 0.78, and 0.39 mg/mL) were applied in all evaluations. Overall antioxidant activity was expressed as the concentration of substrate that decreased DPPH radical levels by 50% (IC50DPPH) for 7 methanol and 7 ethanol extracts. A comparison of IC50DPPH allowed us to conclude that the methanol extracts are more active in scavenging stable DPPH radicals than are the ethanol extracts. The substrate with antioxidant properties most suitable for cultivation of P. hepiali was rice supplemented with non-defatted soy flour. The extract most effective in scavenging stable radicals was the methanol extract of sample 4 (IC50DPPH = 2.33 mg/mL) cultivated on rice with nondefatted soy flour. The methanol extract of sample 7 cultivated on peas was less effective (IC50DPPH = 11.50 mg/mL). By crystallizing these extracts, we managed to obtain sufficient quantities of 6 samples in a solid state, for which infrared spectra were measured and confirmed the presence of amino acids in the extracts.

Variation of Bioactive Compounds and Antioxidant Activity of Jujube (Ziziphus jujuba) Fruits at Different Stages of Ripening

Fruits of two jujube (Ziziphus jujuba Mill.) cultivars were collected at four stages of ripening and analyzed in terms of chemical compounds. The cultivars were grown under the climatic conditions of the Sub-Carpathian area Ramnicu-Valcea in Romania (45°6′17″N, 24°22′32″E). Total phenols content, total flavonoids content, organic acids from jujube fruits and related antioxidant activities were investigated during the ripening stages. The antioxidant activity of alcoholic extracts was investigated by the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. Total phenolic content was determined by using the Folin-Ciocalteu assay, while determination of flavonoids was done by aluminium nitrate colorimetric method, and organic acids were separated by reversed phase chromatography. The results obtained have indicated significant differences (p < 0.05) found in bioactive compounds and antioxidant activity, depending on cultivars and ripening stage. Total phenolic content ranged from 1634.44 to 472.38 mg GAE/100 g in methanolic extracts of the two varieties studied, while total flavonoids content ranged from 19.9 to 48.5 mg QE/100 g. As regards the influence of ripening stage, the results show that the highest antioxidant activity was recorded in the stage of white maturity. The impact of maturity stage was significant on organic acid distribution of jujube extracts, and ascorbic acid is the major organic acid found in jujube fruits, followed by malic acid and lactic acid. Jujube fruits are rich in bioactive compounds and can be a complement in human’s healthy eating.

Evaluation of antioxidant activities of saffron stigma and spath as by-product of Crocus sativus L

The present study aimed to estimate and compare, using in vitro assays, the antioxidant activities of alcoholic extracts of saffron stigma and spath as by-products of the saffron crop. The antioxidant activity was evaluated using in vitro assays such as total antioxidant capacity, DPPH free radical, Scavenging of H2O2, FRAP and β-carotene bleaching assay. The results allowed us to evidence the presence of products with antioxidant and bioactive capacities in spaths and stigmas of Crocus sativus. The response of each extract depends on the type of the test. Extract from spaths protect β-carotene from bleaching more than the extract of stigmas and extract from stigmas revealed a significant reducing power activity than that of spaths. As a result, we can consider these extracts especially that of spaths like a new source of antioxidant compounds.

Atividade de sequestramento de radical livre dos extratos etanólicos das folhas de Anacardiaceae

Os radicais livres são responsáveis por causar muitas doenças crônicas e degenerativas. Os antioxidantes são substâncias capazes de eliminar radicais livres e impedi-los de causar danos celulares. Neste contexto, a atividade antioxidante dos extratos alcoólicos das folhas de Anacardium occidentale e Myracrodruon urundeuva foi avaliada pelos métodos de 2,2- difenil-1-picrilhidrazil (DPPH) e 2,2’-azinobis-(3-etil-benzothiazolin-6-sulfónico ácido) (ABTS). O conteúdo fenólico e análise fitoquímica dos extratos também foram avaliados. As duas espécies exibiram atividade sequestradora de radicais livres. Estes resultados estão relacionados com alto teor de compostos fenólicos encontrados nos extratos. M. urundeuva mostrou atividade antioxidante semelhante ao butilhidroxitolueno (BHT), se tornando uma fonte promissora de antioxidante natural.

Phenolics Content, Antioxidant Activity and Color of Green Walnut Extracts for Preparing Walnut Liquor

Different extracts prepared from green fruits of ‘Sibisel 44’ walnut cultivar were investigated for their total phenolics and flavonoids, antioxidant activity, individual phenolics content and colour component. Extracts were prepared using three variants, to analyze the effect of solvent concentration and sugar addition on properties of green walnuts extracts. The antioxidant activity of alcoholic extracts was investigated by the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method while total phenolic content was determined by using the Folin-Ciocalteu assay. Seventeenindividual phenolics were detected and quantified by using HPLC in walnut green fruit extracts. For total phenolics and flavonoids extraction from green walnut fruits 70% ethanol was more efficient. Highest concentration was found in samples with 70% ethanol for gallic, vanillic, chlorogenic, caffeic, syringic, salicylic, ellagic acids, juglone, catechin, epicatechin, myricetin, and quercetin. The use of 40% ethanol led to a significant increase of ferulic acid and rutin content, while the greatest amount of rutin was extracted using 40% ethanol and sugar.

Phenolics Content, Antioxidant Activity and Color of Green Walnut Extracts for Preparing Walnut Liquor

Different extracts prepared from green fruits of ‘Sibisel 44’ walnut cultivar were investigated for their total phenolics and flavonoids, antioxidant activity, individual phenolics content and colour component. Extracts were prepared using three variants, to analyze the effect of solvent concentration and sugar addition on properties of green walnuts extracts. The antioxidant activity of alcoholic extracts was investigated by the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method while total phenolic content was determined by using the Folin-Ciocalteu assay. Seventeenindividual phenolics were detected and quantified by using HPLC in walnut green fruit extracts. For total phenolics and flavonoids extraction from green walnut fruits 70% ethanol was more efficient. Highest concentration was found in samples with 70% ethanol for gallic, vanillic, chlorogenic, caffeic, syringic, salicylic, ellagic acids, juglone, catechin, epicatechin, myricetin, and quercetin. The use of 40% ethanol led to a significant increase of ferulic acid and rutin content, while the greatest amount of rutin was extracted using 40% ethanol and sugar.

Phenolic composition and comparison of antioxidant activity of alcoholic extracts of Peppermint (Mentha piperita)

Peppermint (Mentha piperita) has long been regarded as a food and medicinal plant. At the present work, the antioxidant activity of the methanol, ethanol and methanol/ethanol (1:1) extracts of leaf fraction through various in vitro models was investigated in Iranian peppermints for the first time. Total phenol, flavonoid and anthocyanin contents were also determined. Our results showed the alcoholic extracts had different responses with different antioxidant methods. The methanol extract had maximum phenol content (3.57 ± 0.26 g Gallic acid/100 g Peppermint powder) and showed best superoxide radical (47.05 ± 0.85 %) and hydrogen peroxide (91.05 ± 1.50 %) scavenging activities. The methanol/ethanol (1:1) extract had maximum flavonoid (3.33 ± 0.12 g quercetin/100 g Peppermint powder) and anthocyanin contents (1.74 ± 0.21 g/100 g Peppermint powder) and showed best DPPH radical scavenging activity (82.82 ± 2.57 %, IC50 = 10.02 ± 0.63 mg/mL) as well as ferric reducing power (184.22 ± 14.10 μmol/100 g Peppermint powder). The ethanol extract only showed the highest nitric oxide radical scavenging activity (80.13 ± 7.12 %). Chlorogenic acid, rutin, and caffeic acid were found by HPLC analysis of the main phenolic components. These results show, Peppermint alcoholic extracts can be used as a natural antioxidants to reduce oxidative stress in human beings and as a possible food supplement or in pharmaceutical applications.

Antimicrobial and antioxidant activities of alcoholic extracts of Rumex dentatus L.

In-vitro antimicrobial and antioxidant activities of various concentrations ranging from 150 to 500 μg/ml of alcoholic (methanol and ethanol) extracts of Rumex dentatus were analyzed on different clinical bacterial strains (Shigella flexneri, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus) and fungal strains (Aspergillus versicolor, Aspergillus flavus, Acremonium spp., Penicillium dimorphosporum, Candida albicans, Candida kruesie, Candida parapsilosis) using agar disk diffusion method and broth dilution method (MIC and MBC determination) for antimicrobial activity and DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, Riboflavin photo-oxidation assay, deoxyribose assay, lipid peroxidation assay for antioxidant activity. The extracts showed maximum inhibitory effect against K. pneumonia and P. aeruginosa with no activity against S. typhimurium from among the bacterial strains while as in case of the fungal strains the maximum effect was observed against C. albicans by both the extracts. MIC and MBC values determined for active fractions of the extracts against some bacterial strains (S. flexneri, K. pneumonia and E. coli) revealed that the test organisms were inhibited by all the extracts with methanol showing lower values of both MIC and MBC indicating it as a better antimicrobial agent. The antioxidant activity showed that the extracts exhibited scavenging effect in concentration-dependent manner on superoxide anion radicals and hydroxyl radicals leading to the conclusion that the plant has got a broad spectrum antimicrobial and antioxidant activity and could be a potential alternative for treating various diseases.

EXAMINATION OF THE ANTIOXIDANT ACTIVITY OFHABERLEA RHODOPENSISLEAF EXTRACTS AND THEIR PHENOLIC CONSTITUENTS

ABSTRACT The present study investigated Haberlea rhodopensis Friv. – a less-explored Balkan endemic plant. The purpose was to determine the total phenolic content and antioxidant activity of alcohol extracts derived from the leaves of H. rhodopensis Friv. by applying reliable methods. The phenolic concentration in the examined extracts, calculated as mg gallic acid equivalent (GAE)/g leaf dry weight (DW), ranged from 99.03 to 151.24 mg GAE/g DW. The results from the total phenolics assay and the antioxidant activity tests were significantly correlated. The methanol and 70% ethanol extracts, which had the highest total phenolic content values (151.24 and 150.67 mg GAE/g DW, respectively), ranked the highest radical scavenging activity according to the 2,2′-azino-bis-3- ethylbenzothiazoline-6-sulfonic acid assay (1.451 and 1.343 mMTE/g DW, respectively). The major phenolic acids and some flavonoid aglycones and glycosides were analyzed by high-performance liquid chromatography. Luteolin (2,706.20 µg/g DW), hesperidin (2,641.46 µg/g DW), sinapic acid (1,296.78 µg/g DW) and ferulic acid (619.80 µg/g DW) were predominant in the H. rhodopensis 70% alcohol extract. PRACTICAL APPLICATIONS The research yielded novel information about Haberlea rhodopensis, a less-explored endemic plant. The aim of the present study was to determine the antioxidant capacity of this resurrection plant with a focus on phenolic antioxidants rather than enzymes. High-performance liquid chromatography analysis was performed to quantify the major phenolic acids and flavonoids. The antioxidant potential of the extracts obtained was estimated using different approved methods. The results suggested the possibility of practical application of H. rhodopensis leaf extracts because of the established free radical-scavenging activity.

Investigation of antioxidant activity of alcoholic extract of Globularia alypum L.

Hydroethanolic extract from leaves of Globularia alypum L. (HEGA), Globulariaceae, was screened for its content on total polyphenols, flavonoids and anthocyanins. Its antioxidant activity was also assessed in chemical and biological systems. Analysis of the antioxidant compounds reveals that the HEGA contains high amounts of polyphenols, flavonoids and anthocyanins. Besides, it shows a significant antioxidant activity. When tested in HeLa cells, the extract exerts an antiproliferative effect. The concentration leading to a 50% inhibition was estimated at 1.53 mg/ml. The pretreatment of HeLa cells with non cytotoxic concentration of the leaf extract protects them from Fe2+ and hydrogen peroxide induced oxidative stress. A good protection against lipid peroxidation was obtained and evidenced by a decrease in the level of two lipid peroxidation (LPO) products, Malodialdehyde (MDA) and conjugated dienes (CD). Besides, a decrease in catalase and superoxide dismutase (SOD) activities was obtained. This suggests a recovery of the oxidative balance in the treated cells. Key words: Globularia alypum, oxidative stress, cell culture, malondialdehyde, superoxide dismutase, catalase.

Evaluation of Antioxidant Activity of Alcoholic Extract from Peanut Hulls

In this article, the antioxidant activity of the crude extract from peanut hulls was tested with phosphomolybdenum complex method, the reduction of K3Fe(CN)6 and DPPH assay. The IC50 value for DPPH radical scavenging lied 14.86μg ml-1, and 28 μg mL-1 of PHF exhibited total antioxidant activity and reducing power which were comparable to that of the ascorbic acid standard at 52.41 and 15.41 μg mL-1, respectively.

Evaluation of antioxidant profile and activity of amalaki (Emblica officinalis), spirulina and wheat grass

Aqueous and alcoholic extracts of amalki (Emblica officinalis), spirulina and wheatgrass were prepared and analyzed for antioxidant vitamin content (vitamin C and E), total phenolic compounds. Antioxidant status, reducing power and effect on glutathione S-transferase (GST) activity were evaluated in vitro. Vitamin C content of crude amalaki powder was found to be 5.38 mg/g, while very less amount 0.22 mg/g was detected in wheat grass. Amalki was rich in vitamin E like activity, total phenolic content, reducing power and antioxidant activity. Total antioxidant activity of aqueous extract of amalki, spirulina and wheat grass at 1mg/ml concentration were 7.78, 1.33 and 0.278 mmol/l respectively. At similar concentrations the total antioxidant activity of alcoholic extract of amalaki, spirulina and wheat grass was 6.67, 1.73 and 0.380 mmol/l respectively. Amalki was also found to be rich source of phenolic compounds (241mg/g gallic acid equivalent). Alcoholic extract of wheat grass showed 50 % inhibition in FeCl(2)- ascorbic acid induced lipid peroxidation of rat liver homogenates in vitro. Both aqueous and alcoholic extracts of amalaki inhibited activity of rat liver glutathione S-transferase (GST) in vitro in dose dependant manner. Since GST acts as powerful drug metabolizing enzyme its inhibition by amalaki offers possibility of its use for lowering therapeutic dose of herbal preparations. The aqueous extracts of both amalki and spirulina also showed protection against t-BOOH induced cytotoxicity and production of ROS in cultured C(6) glial cells.