Phenolic Com Research Articles

The encapsulation of powdered doum extract in liposomes and its application in yoghurt.

Doum fruit extract has many dietary benefits, but, due to the potential interaction between its phenolic compounds and milk proteins, its antioxidant activity is reduced in dairy formulations. To overcome this problem, encapsulation in liposomes has been used to improve the bioavailability of the phenolic com- pounds by protecting them from oxygen and acids, creating the conditions for better delivery and controlling their release into the body. A liposome was used to encapsulate doum extract powder (DEP), and the encapsu- lated DEP was used to fortify yoghurt. The physicochemical properties of the yoghurt produced, including pH, acidity, water holding capacity and texture, were investigated in fresh yoghurt and after 21 days of stor- age at 4°C. Adding 5% DEP liposome to yoghurt gave a product with characteristics similar to the control sam- ple but with higher antioxidant activity. Doum extract powder has been successfully encapsulated in liposomes. The high encapsulation efficiency, particle size, and TEM examination indicate successful encapsulation of up to 1% DEP. The addi- tion of 5% DEP liposomes into yoghurt had some effects on the development of acidity, textural parameters, and water holding capacity of the yoghurt, compared to a control. The addition of higher percentages of DEP liposomes significantly affected the functional properties of yoghurt. It is recommended that 5% DEP liposomes can be added to yoghurt in order to increase its antioxidant activity.

ATIVIDADE ANTIOXIDANTE, COMPOSTOS FENÓLICOS TOTAIS E TRIAGEM FITOQUÍMICA DE ERVAS CONDIMENTARES DESIDRATADAS

Oxidative stress, resulting from an imbalance betwe en production and elimination of free radicals, has great importance in aging, transformation and cell death. Intake of culinary spices, like as salt substitute s, has been stimulated by the fact that they contain compounds capable of dis abling free radicals. The objective of this study w as to evaluate the antioxidant capacity (DPPH and α- deoxyribose methods), determine the content of to tal phenolic compounds (Folin- Ciocalteu method) and promote a phytochemical screening of aqueous and alcoholic extracts of rosemary ( Rosmarinus officinalis ), green onion ( Allium fistulosum ), cumin ( Cuminum cyminum ), basil ( Ocimum basilicum ), oregano ( Origanum vulgare ), parsley ( Petroselinum crispum ) and thyme ( Thymus vulgaris ). The alcoholic extracts of oregano and parsley we re those with the highest levels of antioxidant activi ty by the method of DPPH (96.0 % and 97.2 %, respectively ), while in the method of α-deoxyribose, the best results were obtained to the alcoholic extracts of rosemary (78.5%), basil (77. 2 %) and oregano (84.7 %). The alcoholic extract of cumin wa s the sample that showed the highest content of tot al phenolic compounds (48.0 %). There was an absence of a significant correlation among the methods for determinin g the antioxidant activity and these with the content of phenolic com pounds. By phytochemical screening, different secondary metabolites were identified, including reducing sugars and terp enes. In conclusion, among the spices evaluated, or egano showed the highest antioxidant activity, as well as one of the highest levels of phenolic compounds, which would justify its use as a functional food ingredient.

Extraction and Characterization of Proanthocyanidins from Grape Seeds

Grape seed contains many polyphenolic compounds that have potential health-promoting benefits. Among the- se compounds are proanthocyanidins, also known as condensed tannins, which is a class of flavanols. The basic structural building blocks of flavanols are polyhydroxyflavan-3-ol units linked together by C-C bonds. They are widely distributed in plants but grape seed has very high contents. This study examined extraction and purification technologies for obtain- ing proanthocyanidins from grape seeds and analytical methods and tools for characterizing them. Proanthocyanidins are polyphenolic compounds that can be found in the plant physiology of several plant species, are mainly concentrated in tree barks and outer skins of seeds. Grape seeds are one of the richest sources of proanthocyanidins (2). Public awareness of the antioxidant and free radical-scavenging abilities of these phenolic com- pounds results largely from the potential of these compounds to increase human health in many ways. Reductions in cardi- ovascular disease, cerebrovascular diseases, and cancer mor- tality are just some of the noticeable examples associated with these phenolic compounds (3-5). Recent advances in the field of nutraceuticals have shown that the compounds found in grapes exhibit even more benefits than initially be- lieved. This paper aims at reviewing these compounds found in the anatomy of the grape seeds and current methods of separation and characterization of proanthocyandins.

Characterization of Cold‐Pressed Onion, Parsley, Cardamom, Mullein, Roasted Pumpkin, and Milk Thistle Seed Oils

Cold-pressed onion, parsley, cardamom, mullein, roasted pumpkin, and milk thistle seed oils were characterized for their fatty acid (FA) composition, tocopherol content, carotenoid profile, total phenolic content (TPC), oxidative stability index (OSI), color, physical properties, and radical-scavenging capaci- ties against peroxyl (oxygen radical-scavenging capacity) and sta- ble DPPH (diphenylpicrylhydrazyl) radicals. Parsley seed oil had the highest oleic acid content, 81 g/100 g total FA, and the low- est saturated fat among the tested oils. Roasted pumpkin seed oil contained the highest level of total carotenoids, zeaxanthin, β- carotene, cryptoxanthin, and lutein at 71 μmol/kg and 28.5, 6.0, 4.9, and 0.3 mg/kg oil, respectively. Onion seed oil exhibited the highest levels of α- and total tocopherols under the experimental conditions. One of the parsley seed oils exhibited the strongest DPPH· scavenging capacity and the highest oxygen radical ab- sorbance capacity (ORAC) value of 1098 μmol Trolox equiv/g oil. However, ORAC values of the tested seed oils were not nec- essarily correlated to their DPPH· scavenging capacities under the experimental conditions. The highest TPC of 3.4 mg gallic acid equiv/g oil was detected in one of the onion seed oils. The OSI values were 13.3, 16.9-31.4, 47.8, and 61.7 h for the milk thistle, onion, mullein, and roasted pumpkin seed oils, respec- tively. These data suggest that these seed oils may serve as dietary sources of special FA, tocopherols, carotenoids, phenolic com- pounds, and natural antioxidants. Paper no. J11246 in JAOCS 83, 847-854 (October 2006). Edible seed oils are a group of important food ingredients. Novel specialty seed oils rich in factors beneficial to health are in high demand because of consumers' interest in disease pre- vention and health promotion through improved diets. These beneficial factors include special FA compositions such as high content of monounsaturated FA (MUFA) or n-3 FA, tocopher- ols, carotenoids, and antioxidative phenolic compounds (1-4). A number of edible oils from herb, spice, and fruit seeds have been shown to contain special FA profiles (4). For instance, American ginseng seed oil contains about 87% oleic acid, and basil seed oil has 57-63% α-linolenic acid (18:3n-3), the es- sential n-3 FA (4). The cold-pressed edible seed oils may be preferred by consumers because the cold-pressing procedure involves neither heat nor chemicals, and may increase the re- tention of beneficial phytochemicals. Previous studies showed that cold-pressed carrot seed oil had about 82% oleic acid (18:1n-9), which has been associated with lowering the risk of cardiovascular disease (5). Cold-pressed edible hemp and berry fruit seed oils contain significant levels of α-linolenic acid (18:3n-3), which may be converted to the longer-chain n-3 PUFA, EPA (20:5n-3) and DHA (22:6n-3), in vivo through elongation and desaturation reactions. EPA and DHA poten- tially reduce the risk of cancer, heart disease, hypertension, and autoimmune disorders (6-8). These data suggest the possibility of developing novel edible seed oils with special FA composi-

Characterization of bioactive compounds contained in vegetables of the Solanaceae family by capillary electrophoresis; 172–186

Because of their antioxidative capability polyphenols and vitamins are the most important naturally occurring compounds. Several widely consumed vegetables are rich in various phenolic compounds and vitamins. In this study, such vegetables as tomato ( Solanum lyco- persicum), eggplant (Solanum melongena), chilli pepper ( Capsicum annuum), and potato (Solanum tuberosum) of the Solanaceae family were investigated. The phenolic com pounds and vitamins were separated and their composition was determined by capillary electrophoresis (CE). The total phenolic content was measured according to the Price and Butler met hod. In addition, the antioxidative capability of phenolic compounds was monitored and evaluated by CE using a coloured free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH).

Phenolic constituents from the lichen Parmotrema stuppeum (Nyl.) Hale and their antioxidant activity.

Lichen, Parmotrema stuppeum (P. stuppeum) was successively extracted with benzene and acetone. Both the extracts were fractionated on 1% oxalic acid impregnated silica gel column to obtain four phenolic compounds. The structures of compounds were identified by 1H and 13C NMR spectra as methyl orsenillate, orsenillic acid, atranorin and lecanoric acid respectively. Antioxidant activity of benzene extract, acetone extract and isolated compounds were evaluated in a beta-carotene-linoleate model system. The pure compounds showed moderate antioxidant activity. This is the first report on the isolation and characterisation of compounds from the lichen P. stuppeum as well as on their antioxidant activity.

Structural Elements of Sporopollenin from the Pollen of Torreya californica Torr. (Gymnospermae): Using the 1H-NMR Technique

Abstract Sporopollenin was isolated and purified from pollen of the gymnospermae Torreya californica using an enzymatic treatment followed by extraction with organic solvents. 1H -NMR (ID and 2D) was used for analysis of this biopolym er and reveals the presence of three phenolic com pounds. Comparison with the analysis of sporopollenin from the angiospermae Typha angustifolia L. shows high similarity between the aromatic compounds

Tissue localization of phenolic compounds in plants by confocal laser scanning microscopy

laser scanning microscopy, UV-screening pigments, Picea abies (L.) Karst., Vicia faba L., Secale cereale L., Equisetum Phenolic compounds are involved in many interactions arvense L. of plants with their biotic and abiotic environment. These substances accumulate in different plant tissues and cells during ontogenesis and under the influ- Introduction ence of various environmental stimuli, respectively. Studies on the tissue localization of phenolic com- Phenolic compounds play a major role in the interaction

Effects of Nutrient Enrichment on Growth and Herbivory of Dwarf Red Mangrove (Rhizophora Mangle)

The objectives of this study were to determine responses by red mangrove (Rhizophora mangle) and its primary consumers to nutrient enrichment, to determine if nutrient limitation is responsible for the dwarf plant form of red mangrove, and to evaluate four competing hypotheses for the relation of nutrient status and invertebrate herbivory. In a factorial-designed experiment, I fertilized 48 dwarf trees along gradients of tidal elevation and water depth at Twin Cays, an intertidal mangrove island in Belize, Central America, and measured plant growth responses and herbivory for 2 yr. At the end of year- 2, I compared biomass accumulation and analyzed plant tissue for chemical and structural composition. Dwarf red mangrove trees on this tidal island responded quickly and grew vigorously when treated with P and NPK fertilizers. Leaf number, leaf area, branching, shoot length, and aerial root production increased dramatically over 2 yr. N-fertilized trees grew very slowly and their responses were not different from Control trees. N-fertilized and Control trees changed little over 2 yr. Some responses to phosphorus-containing fer- tilizers vary by water depth and tidal elevation, but physicochemical factors do not explain the differences in growth responses. I conclude that phosphorus availability is a major factor limiting red mangrove growth at my study site in the interior of Twin Cays. Herbivory by two specialized, endophytic insect species (Ecdytolopha sp., which feeds in apical buds, and Marmara sp., which mines stem periderm) increased in P- and NPK-fertilized trees compared to N-fertilized and Control trees. Twice as many apical buds were damaged or destroyed and the frequency of mines increased by 6-8 fold. However, fertilization had no effect on feeding rates and standing damage by a leaf-feeding guild of generalist herbivores or on the frequency of shoots killed by stem borers. Herbivory by the two specialists was not related to C:N ratios, but it was inversely related to concentrations of phenolic com- pounds. Neither nutrient ratios nor concentrations of phenolics affected rates of herbivory by the generalist folivores. Although sclerophylly of red mangrove leaves decreased in P- and NPK-fertilized trees but not in N-fertilized and Control trees, there was no relationship between leaf toughness and herbivory by generalist folivores. These data suggest that sclerophylly in oligotrophic ecosystems may be an adaptive mechanism related to nutrient conservation, and that it is associated with red mangrove survival in phosphorus-deficient soil rather than an adaptation to herbivory.

On the Occurrence of Caffeoyltartronic Acid and Other Phenolics in Chondrilla juncea

Abstract Caffeoyltartronic acid and other eleven phenolic com pounds were identified in the MeOH extract of Chondrilla juncea: the flavonoids luteolin, luteolin-7-glucoside, luteolin-7-galactosylglucuronide and quercetin-3-galactoside; the phenolic acids protocatechuic, caffeic, chlorogenic, isochlorogenic and isoferulic and the coumarins cichoriin and aesculetin. The taxonomic im plications of these com pounds have been discussed.

Lipophilic Phenolic Constituents from Helichrysum Species Endemic to Madagascar

Abstract Eight species of the genus Helichrysum, all of them endemic to Madagascar, were analyzed for lipophilic phenolic constituents deposited on the surfaces of leaves and stems. A total of 35 compounds was isolated and identified by spectroscopic means. Chalcones (10) comprised the largest group of compounds encountered, followed by flavonols (8), flavanones (7), flavones (4), benzophenones (3) and phloroglucinol derivatives (3). Many of the flavonoids were characterized by unsubstituted B-rings and/or C- or O-bound prenyl or neryl substituents. The Helichrysum species analyzed in this study are very similar to African species of this genus with regard to their lipophilic phenolic constituents. The phenolic com pounds studied thus appear to be conservative chemical characters of Helichrysum that were retained more or less unchanged during the origin of endemic taxa in Madagascar.