chlorophyll-a and 1-1-diphenyl-2-picrylhydrazyl

The use of higher plants for the production of plant growth biostimulants is receiving increased attention among scientists, farmers, investors, consumers and regulators. The aim of the present study was to examine the possibility of converting plants commonly occurring in Europe (St. John's wort, giant goldenrod, common dandelion, red clover, nettle, valerian) into valuable and easy to use bio-products. The biostimulating activity of botanical extracts and their effect on the chemical composition of celeriac were identified. Plant-based extracts, obtained by ultrasound-assisted extraction and mechanical homogenisation, were tested in field trials. It was found that the obtained formulations increased the total yield of leaves rosettes and roots, the dry weight of leaves rosettes and roots, the content of chlorophyll

Topics: Antioxidants; Apium; Ascorbic Acid; Benzothiazoles; Biphenyl Compounds; Carotenoids; Chemistry, Pharmaceutical; Chlorophyll; Chlorophyll A; Europe; Fatty Acids; Horticulture; Nitrates; Photosynthesis; Picrates; Pigmentation; Plant Extracts; Plant Leaves; Plant Roots; Polyphenols; Sulfonic Acids; Ultrasonics

Drought stress is one of the most important environmental factors that limit plant growth. Canola is an important agricultural crop grown primarily for its edible oil. In this study, penconazole (PEN), a triazole growth regulator, and calcium (Ca

Topics: Adaptation, Physiological; Biphenyl Compounds; Brassica rapa; Calcium; Calmodulin; Carotenoids; Chlorophyll; Droughts; Gene Expression Regulation, Plant; Genes, Plant; Indoleacetic Acids; Peroxidases; Phosphorus; Picrates; Plant Growth Regulators; Potassium; Protein Kinases; Reverse Transcriptase Polymerase Chain Reaction; Succinate Dehydrogenase; Triazoles

Plantago ovata Forsk is an annual herb with immense medicinal importance, the seed and husk of which is used in the treatment of chronic constipation, irritable bowel syndrome, diarrhea since ancient times. Zinc, an essential metal, is required by plants as they form important components of zinc finger proteins and also aid in synthesis of photosynthetic pigments such as chlorophyll. However, in excess amount Zn causes chlorosis of leaf and shoot tissues and generate reactive oxygen species. The present study is aimed at investigating the changes in expression levels of MT2 gene in Plantago ovata under zinc stress. Data show up to 1.66 fold increase in expression of PoMT2 in 1000 µM ZnSO

Topics: Biphenyl Compounds; Chlorophyll; Chlorophyll A; Dose-Response Relationship, Drug; Gene Expression Regulation, Plant; Metallothionein; Oxidation-Reduction; Oxidative Stress; Picrates; Plant Extracts; Plant Proteins; Plant Roots; Plant Shoots; Plantago; Seedlings; Seeds; Zinc Sulfate

Honeysuckle (Lonicera japonica Thunb.) is a traditional medicinal plant in Chinese, and chlorogenic acid and luteolosid are its specific bioactive phenolic compounds. This study was to investigate leaf antioxidant responses in honeysuckle to saline stress with emphasis on phenolics through hydroponic experiments and field trials. NaCl stress did not stimulate antioxidant system including superoxide dismutase, ascorbate peroxidase, catalase and ascorbate, and had no significant effect on lipid peroxidation in the leaves. Consistently, no inhibition on photochemical capacity of photosystems suggested that reactive oxygen species (ROS) was maintained at a normal level under NaCl stress. However, leaf phenolic synthesis was activated by NaCl stress, indicated by elevated genes transcription and activity of phenylalanine ammonia-lyase and increased phenolics concentration. Specifically, leaf chlorogenic acid concentration was increased by 67.43% and 48.86% after 15 days of 150 and 300 mM NaCl stress, and the increase of luteolosid concentration was 54.26% and 39.74%. The accumulated phenolics hardly helped detoxify ROS in vivo in absence of oxidative stress, but the elevated phenolic synthesis might restrict ROS generation by consuming reduction equivalents. As with NaCl stress, soil salinity also increased concentrations of leaf phenolics including chlorogenic acid and luteolosid without exacerbated lipid peroxidation. In conclusion, leaf phenolics accumulation is a mechanism for the acclimation to saline stress probably by preventing oxidative stress in honeysuckle; leaf medicinal quality of honeysuckle can be improved by saline stress due to the accumulation of bioactive phenolic compounds.

Topics: Antioxidants; Biphenyl Compounds; Chlorogenic Acid; Chlorophyll; Chromatography, High Pressure Liquid; Fluorescence; Free Radical Scavengers; Gene Expression Regulation, Plant; Hydroponics; Lonicera; Malondialdehyde; Oxidative Stress; Phenols; Phenylalanine Ammonia-Lyase; Photosynthesis; Picrates; Plant Leaves; Reference Standards; Seasons; Sodium Chloride; Stress, Physiological; Transcription, Genetic

Context Seaweeds from the Mexican Pacific Ocean have not been evaluated as a source of chemoprotectants. Objective The objective of this study is to evaluate chemopreventive activities of the seaweeds Phaephyceae - Padina durvillaei (Dictyotaceae) - Rodhophyceae - Spyridia filamentosa (Spyridiaceae), Gracilaria vermiculophylla (Gracilariaceae) - and Chlorophyceae - Ulva expansa (Ulvaceae), Codium isabelae (Codiaceae), Rhizoclonium riparium (Cladophoraceae) and Caulerpa sertularioides (Caulerpaceae). Materials and methods Methanol, acetone and hexane seaweed extracts were assessed at 30 and 3 mg/mL on antioxidant capacity (DPPH and ABTS assays), 0.003-3.0 mg/plate on antimutagenic activity against AFB1 using Salmonella typhimurium TA98 and TA100 tester strains in Ames test, and 12.5 to 100 μg/mL on antiproliferative activity on Murine B-cell lymphoma. Phenols, flavonoids and pigments content were also assessed as antioxidant compounds. Results Extraction yield was higher in methanol than in acetone and hexane extracts (6.4, 2.7 and 1.4% dw). Antioxidant capacity was higher in brown and green than in red seaweed species, particularly in P. durvillaei extracted in acetone (EC50  value= 16.9 and 1.56 mg/mL for DPPH and ABTS). Flavonoids and chlorophylls were identified as mainly antioxidant components; particularly in hexane extracts, which were correlated with the antioxidant capacity. Highest mutagenesis inhibition (> 40%) occurred in R. riparium at the lowest concentration assayed (0.003 mg/plate), while highest antiproliferative inhibition (37 and 72% for 12.5 and 25 μg/mL) occurred in C. sertularioides. Discussion and conclusion Flavonoids and chlorophylls explained the chemopreventive activities assessed in S. filamentosa, R. riparium and C. sertularioides. These seaweeds have a high potential as a source of novel chemoprotectants.

Topics: Animals; Antimutagenic Agents; Antineoplastic Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Cell Line, Tumor; Cell Proliferation; Chlorophyll; Dose-Response Relationship, Drug; Flavonoids; Lymphoma, B-Cell; Mexico; Mice; Mutation; Picrates; Salmonella typhimurium; Seaweed; Solvents; Sulfonic Acids

Virgin olive oils (VOOs) obtained from the fruits of Croatian autochthonous varieties Mašnjača and Krvavica were extensively characterized for the first time. Investigated oils were compared with the oil obtained from Italian variety Leccino, grown and processed under the same conditions. Headspace volatile profile, tocopherols, chlorophylls, carotenoids and total phenolic content, peroxide value, % acidity, K232, K270 as well as antioxidant activity (DPPH) of the oils' hydrophilic fractions (HFs) including their phenolic composition were assessed by means of HS-SPME/GC-MS, HPLC-FL, HPLC-DAD and spectrophotometric methods, respectively. Most of the studied quality parameters varied between the cultivars. The main volatile compounds detected in all tested olive oils were the C6 compounds derived from polyunsaturated fatty acids through the lipoxygenase pathway. Krvavica oil was characterized by hexanal (8.8%-9.4%). Leccino oil contained the highest percentage of (E)-hex-2-enal (73.4%-74.0%), whereas (Z)-hex-3-enal (21.9%-25.0%) and (E)-hex-2-enal (27.6%-28.9%) dominated in Mašnjača oil. Leccino oil contained the highest amount of tocopherols (312.4 mg/kg), chlorophylls (7.3 mg/kg), carotenoids (4.2 mg/kg) and total phenols (246.6 mg/kg). The HF of Leccino oil showed the highest antioxidant capacity (1.3 mmol TEAC/kg), while the HFs of Mašnjača and Krvavica oils exhibited the activity of 0.5 mmol TEAC/kg.

Topics: Biphenyl Compounds; Carotenoids; Chlorophyll; Chromatography, High Pressure Liquid; Croatia; Free Radical Scavengers; Free Radicals; Italy; Limit of Detection; Oils, Volatile; Olea; Olive Oil; Phenols; Phytochemicals; Picrates; Plant Oils; Spectrophotometry, Ultraviolet; Tocopherols

The aim of this study was to investigate the possibility to use the bioactive components from cape gooseberry (Physalis peruviana), blueberry (Vaccinium corymbosum), and cranberry (Vaccinium macrocarpon) extracts as a novel source against oxidation in food supplementation. The quantitative analysis of bioactive compounds (polyphenols, flavonoids, flavanols, carotenoids, and chlorophyll) was based on radical scavenging spectrophometric assays and mass spectrometry. The total phenolic content was the highest (P < 0.05) in water extract of blueberries (46.6 ± 4.2 mg GAE/g DW). The highest antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and Cupric reducing antioxidant capacity were in water extracts of blueberries, showing 108.1 ± 7.2 and 131.1 ± 9.6 μMTE/g DW with correlation coefficients of 0.9918 and 0.9925, and by β-carotene linoleate assay at 80.1 ± 6.6 % with correlation coefficient of 0.9909, respectively. The water extracts of berries exhibited high binding properties with human serum albumin in comparison with quercetin. In conclusion, the bioactive compounds from a relatively new source of gooseberries in comparison with blueberries and cranberries have the potential as food supplementation for human health. The antioxidant and binding activities of berries depend on their bioactive compounds.

Topics: Biphenyl Compounds; Carotenoids; Chlorophyll; Dietary Supplements; Flavonoids; Free Radical Scavengers; Fruit; Humans; Oxidation-Reduction; Physalis; Picrates; Plant Extracts; Polyphenols; Protein Binding; Serum Albumin; Vaccinium; Vaccinium macrocarpon

To investigate the mechanisms of adaptation and tolerance to ionizing radiation using chronic radiation in wheat.. We exposed wheat plants to chronic gamma irradiation (50 Gy) for 2, 4, and 6 weeks and measured various biological parameters.. Plant height was reduced by exposure to gamma irradiation; this effect increased with increasing exposure time. Photosynthetic pigment levels decreased with increasing exposure time, while anthocyanin levels significantly increased after exposure to gamma rays. The activities of antioxidant enzymes (superoxide dismutase [SOD], ascorbate peroxidase [APX], catalase [CAT], and peroxidase [POD]) and malondialdehyde (MDA) levels increased with increasing duration of exposure to gamma irradiation. Electron spin resonance (ESR) signals were strongly detected in wheat that was gamma-irradiated for two weeks and then gradually decreased with increasing exposure time. The expression of anthocyanin biosynthesis genes (flavanone 3-hydroxylase [F3H], dihydroflavonol reductase [DFR], anthocyanin reductase [ANS], and UDPG-flavonoid glucosyl transferase [UFGT]) and sugar contents increased after exposure to gamma rays.. This suggests that exposure to ionizing radiation according to increase of exposure time has led to efficient induction of anthocyanin and antioxidant enzyme activities. This study indicates that reactive oxygen species (ROS) is eliminated by biosynthesis of anthocyanin and antioxidant enzymes. This study helps elucidate the biological effects of various durations of low-dose exposure to chronic gamma radiation in wheat plants.

Topics: Anthocyanins; Antioxidants; Biphenyl Compounds; Carotenoids; Chlorophyll; Gene Expression Regulation, Plant; Malondialdehyde; Oxidative Stress; Picrates; Time Factors; Triticum

The recent introduction of the cultivation of Stevia rebaudiana Bertoni in Mexico has gained interest for its potential use as a non-caloric sweetener, but some other properties of this plant require studies. Extracts from two varieties of S. rebaudiana Bertoni adapted to cultivation in Mexico were screened for their content of some phytochemicals and antioxidant properties. Total pigments, total phenolic and flavonoids contents of the extracts ranged between 17.7-24.3 mg/g, 28.7-28.4 mg/g, and 39.3-36.7 mg/g, respectively. The variety "Criolla" exhibited higher contents of pigments and flavonoids. Trolox equivalent antioxidant capacity ranged between 618.5-623.7 mM/mg and DPPH decolorization assay ranged between 86.4-84.3%, no significant differences were observed between varieties. Inhibition of β-carotene bleaching ranged between 62.3-77.9%, with higher activity in the variety "Criolla". Reducing power ranged between 85.2-86% and the chelating activity ranged between 57.3-59.4% for Cu²⁺ and between 52.2-54.4% for Fe²⁺, no significant differences were observed between varieties. In conclusion, the results of this study showed that polar compounds obtained during the extraction like chlorophylls, carotenoids, phenolic compounds and flavonoids contribute to the antioxidative activity measured. The leaves of S. rebaudiana Bertoni could be used not only as a source of non-caloric sweeteners but also naturally occurring antioxidants.. La reciente introducción del cultivo de Stevia rebaudiana Bertoni en México ha ganado interés debido a su potencial uso como fuente de edulcorantes no calóricos, pero otras propiedades de esta planta aun requieren de estudios. Extractos de hojas de dos variedades de S. rebaudiana Bertoni adaptadas al cultivo en México fueron evaluados en cuanto a su contenido de algunos fitoquímicos y sus propiedades antioxidantes. El contenido de pigmentos, fenoles totales y flavonoides en los extractos, osciló entre 17.7-24.3 mg/g, 28.7-28.4 mg/g, y 39.3-36.7 mg/g, respectivamente. La variedad “Criolla” exhibió los mayores contenidos de pigmentos y flavonoides. La capacidad antioxidante equivalente de Trolox osciló entre 618.5-623.7 mM/mg y el ensayo de decoloración del radical DPPH osciló entre 86.4-84.3%, no observándose diferencias significativas entre ambas variedades. La inhibición de la decoloración del -caroteno osciló entre 62.3-77.9%, siendo mayor en la variedad “Criolla”. El poder reductor osciló entre 85.2-86%, las capacidades quelantes de cobre y hierro oscilaron entre 57.3-59.4% y 52.2-54.4%, respectivamente, no observándose diferencias significativas entre ambas variedades. En conclusión, los resultados de este estudio demuestran que los compuestos de naturaleza polar obtenidos durante la extracción, tales como pigmentos clorofílicos, carotenoides, compuestos fenólicos y flavonoides contribuyen a la actividad antioxidante. Las hojas de S. rebaudiana Bertoni podrían ser empleadas no solo como fuente de edulcorantes no calóricos, sino también como fuente de antioxidantes de origen natural.

Topics: Antioxidants; Benzothiazoles; beta Carotene; Biphenyl Compounds; Bleaching Agents; Chelating Agents; Chlorophyll; Copper; Drug Evaluation, Preclinical; Flavonoids; Free Radical Scavengers; Humans; Iron; Mexico; Oxidation-Reduction; Phenols; Picrates; Pigments, Biological; Plant Extracts; Plant Leaves; Stevia; Sulfonic Acids

Cistus heterophyllus subsp. carthaginensis is an endemic and endangered species from the SE Mediterranean coastal region of Spain. Within the framework of the efforts aiming to species conservation, in vitro culture techniques could be of interest. The aim of this study was to evaluate the antioxidant capacity of C. heterophyllus shoot cultures as a possible marker of in vitro performance. The effects of five different basal salt formulations and cytokinin levels on in vitro performance and antioxidant capacity were examined. K(+)/Na(+) and Ca(2+)/Na(+) ratios initially present in culture media greatly affected the antioxidant capacity (the lower the ratios the higher the antioxidant capacity). Increasing concentrations of BA resulted in higher antioxidant capacity. The results obtained point to antioxidant capacity as being a marker of incidence of stress conditions in in vitro cultured C. heterophyllus. A good correlation was found between antioxidant capacity and total soluble phenolics present in Cistus extracts. Catechin was identified in all the extracts and its levels were found to change parallel to the antioxidant capacity, pointing to a prominent role played by this flavonoid in C. heterophyllus defence against oxidative stress, which in turn affects the in vitro performance of this species.

Topics: Antioxidants; Biphenyl Compounds; Calcium; Carotenoids; Chlorophyll; Cistus; Culture Media; Cytokinins; Endangered Species; Free Radicals; Ions; Oxidative Stress; Phenols; Picrates; Plant Stems; Potassium; Salts; Sodium

The effects of short-term ultraviolet B (UV-B) irradiation on sweet basil (Ocimum basilicum L. cv. Cinnamon) plants at the 3-4 leaf pair and flowering stages were examined in controlled environment growth chambers. Plants were exposed to 0 (reference), 2 and 4 kJ UV-B m(-2) day(-1) over 7 days.. Exposure of basil plants to supplementary UV-B light resulted in increased assimilating leaf area, fresh biomass and dry biomass. Stimulation of physiological functions in young basil plants under either applied UV-B dose resulted in increased total chlorophyll content but no marked variation in carotenoid content. At the flowering stage the chlorophyll and carotenoid contents of basil were affected by supplementary UV-B radiation, decreasing with enhanced UV-B exposure. Both total antioxidant activity (2,2-diphenyl-1-picrylhydrazyl free radical assay) and total phenolic compound content were increased by UV-B light supplementation. Young and mature basil plants differed in their ascorbic acid content, which was dependent on UV-B dose and plant age. UV-B radiation resulted in decreased nitrate content in young basil plants (3-4 leaf pair stage).. These results indicate that the application of short-exposure UV-B radiation beneficially influenced both growth parameters and biochemical constituents in young and mature basil plants.

Topics: Antioxidants; Ascorbic Acid; Biomass; Biphenyl Compounds; Carotenoids; Chlorophyll; Flowers; Nitrates; Nitrogen; Ocimum basilicum; Phenols; Phytochemicals; Picrates; Plant Development; Plant Leaves; Ultraviolet Rays

The present research analyses the contribution of some lipid antioxidants to the antioxidant activity of lipophilic extracts from basil by an electron paramagnetic resonance (EPR) study using the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). DPPH assay is considered an easy and accurate method with regard to measuring the antioxidant activity of plant extracts and EPR has already been employed to determine antioxidant activities of lipophilic plant extracts.. Lipid extracts were obtained from basil grown hydroponically for 20 or 35 days from sowing and in soil for 35 days from sowing. Fast and slow rate constants were distinguishable in the decay kinetics of DPPH mixture added with lipid extract. Antioxidants with kinetics characterized by a fast decay rate were tocopherols and chlorophylls, whereas those characterized by a slow decay rate were carotenoids, among which were β-carotene, lutein, β-apo-8'-carotenal and zeaxanthin. The 20-day hydroponically grown sample, which showed higher contents of tocopherol, chlorophyll and carotenoid molecules, was the sample endowed with the higher content of fast lipophilic antioxidants (FLA) and slow lipophilic antioxidants (SLA).. The three samples showed different compositions of FLA and SLA, giving rise to different decay kinetics. Despite the differences, in all samples tocopherol contributed about 0.3% to the bulk of FLA, whereas the figure for chlorophyll was about 40%, evidencing the relevant but little-studied role of chlorophyll as an antioxidant.

Topics: Antioxidants; Biphenyl Compounds; Carotenoids; Chlorophyll; Electron Spin Resonance Spectroscopy; Free Radical Scavengers; Free Radicals; Hydroponics; Kinetics; Lipids; Ocimum basilicum; Picrates; Plant Extracts; Plant Leaves; Tocopherols

The phytochemical composition of carotenoids, tocopherols, free sugars, organic acids, L-ascorbic acid, capsaicinoids, and flavonoids in green and red paprika (GP and RP), and paprika leaves (PL) cultivated in Korea were analyzed. The ethanolic extracts of GP, RP, and PL were obtained with 80% ethanol, and their antioxidative activities were determined by measuring their ABTS and DPPH radical scavenging activities. RP showed the highest contents of capsanthin (58.33 ± 3.91 mg/100 g dry weight) and L-ascorbic acid (1987.25 ± 19.64 mg/100 g dry weight), and main compounds of PL were lutein, chlorophyll, and γ-tocopherol (96.91 ± 14.58, 2136.71 ± 21.11, and 723.49 ± 54.10 mg/100 g dry weight, respectively). RP showed the strongest antioxidant activity (IC(50) = 55.23 ± 6.77 μg/mL in a 2, 2'-azino-di-[3-ethylbenzthiazoline sulphonate] assay and 150.40 ± 8.07 μg/mL in a 2, 2-diphenyl-2-picrylhydrazyl assay), and the antioxidant activity of PL was higher than β-carotene but lower than RP. The results indicate that the amounts of capsanthin and L-ascorbic acid in RP correlate well with antioxidant activity. PL, which has various phytochemicals such as lutein, chlorophyll, and γ-tocopherol, might be used in nutraceuticals and pharmaceuticals for improving human health.

Topics: Antioxidants; Ascorbic Acid; Benzothiazoles; Biphenyl Compounds; Capsicum; Carotenoids; Chlorophyll; Flavonoids; Fruit; gamma-Tocopherol; Lutein; Picrates; Plant Leaves; Republic of Korea; Sulfonic Acids; Xanthophylls

The present research aimed at evaluating the vitamin C, total phenolic content (TPC), phenolic compounds, carotenoids, and chlorophyll contents, as well as antioxidant activity (AAC) of six Actinidia species fruit. Vitamin C, phenolic compounds, carotenoids and chlorophylls were measured using high-performance liquid chromatography. TPC was determined using the Folin-Ciocalteau reagent, and AAC using 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay. The highest concentrations of vitamin C and TPC were found for Actinidia kolomikta fruit (1008.3 and 634.1 mg/100 g fresh weight [FW], respectively). Among phenolic compounds, seven phenolic acids and three flavonoids were identified. The 2,5-dihydroxybenzoic acid prevailed in A. kolomikta (425.54 mg/100 g FW), while tannic acid dominated in other species (4.63-100.43 mg/100 g FW). The largest amounts of chlorophylls and carotenoids were identified as Actinidia macrosperma (4.02 and 2.09 mg/100 g FW, respectively). The AAC of fruit extracts decreased in the order of A. kolomikta > Actinidia purpurea > Actinidia melanandra > A. macrosperma > Actinidia arguta > Actinidia deliciosa according to the DPPH assay.

Topics: Actinidia; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Carotenoids; Chlorophyll; Chromatography, High Pressure Liquid; Flavonoids; Fruit; Phenols; Phylogeny; Picrates; Plant Extracts; Polyphenols; Species Specificity; Tannins

One NaCl-tolerant chrysanthemum (Chrysanthemum morifolium Ramat.) variant (E2) has been developed in a stable form through IN VITRO mutagenesis using ethylmethane sulfonate (EMS) as the chemical mutagen. Salt tolerance was evaluated by the capacity of the plant to maintain both flower quality and yield under stress conditions. Enhanced tolerance of the E2 variant has been attributed to the increased activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and dehydroascorbate reductase (DHAR), and, to a lesser extent of membrane damage than NaCl-treated control plants. Isoform analysis revealed that an increase in total SOD activity in the E2 variant was solely due to significant activation of the Cu/Zn isoform. Elevated levels of carotenoids and ascorbate in E2 leaves have been reflected in their higher free radical scavenging capacity (RSC) expressed in terms of DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging ability. Data reflect that a proper balance between enzymatic and non-enzymatic defence systems is required for combating salinity stress in chrysanthemum. Better performance of the E2 progeny under same salinity stress condition, even in the second year, confirms the genetic stability of the salt-tolerance character. On the whole, the E2 variant, developed through 0.025 % EMS treatment, might be considered as a NaCl-tolerant strain showing positive characters towards NaCl stress.

Topics: Abscisic Acid; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Carotenoids; Chlorophyll; Chrysanthemum; Electron Transport; Flowers; Hydrogen Peroxide; Isoenzymes; Lipid Peroxidation; Mutagenesis; Peroxidase; Photosystem II Protein Complex; Picrates; Proline; Sodium Chloride

The oxidative modification of LDL may play an important role in the early events of atherogenesis. Thus the identification of antioxidative compounds may be of therapeutic and prophylactic importance regarding cardiovascular disease. Copper-chlorophyllin (Cu-CHL), a Cu(2+)-protoporphyrin IX complex, has been reported to inhibit lipid oxidation in biological membranes and liposomes. Hemin (Fe(3+)-protoporphyrin IX) has been shown to bind to LDL thereby inducing lipid peroxidation. As Cu-CHL has a similar structure as hemin, one may assume that Cu-CHL may compete with the hemin action on LDL. Therefore, in the present study Cu-CHL and the related compound magnesium-chlorophyllin (Mg-CHL) were examined in their ability to inhibit LDL oxidation initiated by hemin and other LDL oxidizing systems. LDL oxidation by hemin in presence of H(2)O(2) was strongly inhibited by both CHLs. Both chlorophyllins were also capable of effectively inhibiting LDL oxidation initiated by transition metal ions (Cu(2+)), human umbilical vein endothelial cells (HUVEC) and tyrosyl radicals generated by myeloperoxidase (MPO) in presence of H(2)O(2) and tyrosine. Cu- and Mg-CHL showed radical scavenging ability as demonstrated by the diphenylpicrylhydracylradical (DPPH)-radical assay and estimation of phenoxyl radical generated diphenyl (dityrosine) formation. As assessed by ultracentrifugation the chlorophyllins were found to bind to LDL (and HDL) in serum. The present study shows that copper chlorophyllin (Cu-CHL) and its magnesium analog could act as potent antagonists of atherogenic LDL modification induced by various oxidative stimuli. As inhibitory effects of the CHLs were found at concentrations as low as 1 mumol/l, which can be achieved in humans, the results may be physiologically/therapeutically relevant.

Topics: Atherosclerosis; Biphenyl Compounds; Cardiovascular Diseases; Catalysis; Cells, Cultured; Chlorophyll; Chlorophyllides; Copper; Dose-Response Relationship, Drug; Endothelium, Vascular; Free Radical Scavengers; Free Radicals; Hemin; Humans; Hydrazines; Hydrogen Peroxide; Ions; Iron; Lipid Peroxidation; Lipids; Lipoproteins; Lipoproteins, LDL; Magnesium; Malondialdehyde; Models, Chemical; Octanols; Oxygen; Picrates; Protoporphyrins; Pyrazoles; Pyrimidines; Thiobarbituric Acid Reactive Substances; Thromboplastin; Time Factors; Tyrosine; Umbilical Veins; Water