The protective ability of Mediterranean dietary plants against the oxidative damage: The role of radical oxygen species in inflammation and the polyphenol,flavonoid and sterol contents

Ten hydroalcoholic extracts of edible plants from the Calabria region (Italy) were evaluated for their in vitro antioxidant and antiradical properties and in vivo topical anti-inflammatory activity. All the extracts had radical-scavenging and/or antioxidant properties, the most active plants being hawkweed oxtongue and viper’s bugloss. The best free radical (DPPH·)-scavenging activity was found in hawkweed oxtongue and chicory leaves extracts (IC₅₀ = 25 and 26 μg/ml, respectively). Hawkweed oxtongue, poppy and viper’s bugloss extracts showed the greatest inhibition of linoleic acid oxidation (IC₅₀ = 3 μg/ml). Viper’s bugloss and hawkweed oxtongue extracts had the greatest antioxidant effect on bovine brain peroxidation (IC₅₀ = 11 and 22 μg/ml). All the extracts also showed an anti-inflammatory effect: 300 μg/cm² provoked oedema reductions ranging from 18% to 43%. Cress was the most active plant. Chicory leaves contained the highest amount of phenolics (190 mg/g) whilst Rush crimps contained the highest amount of flavonoids (32.9 mg/g), followed by hawkweed oxtongue (15.8 mg/g). Cress contained the highest number of sterols. Among them, γ-sitosterol (12.2%) and ergost-5-en-3-ol (3β) (4.5%) were found to be the major constituents. Moreover, three of the identified molecules (stigmasta-5,23-dien-3β-ol, stigmasta-5,24(28)-dien-3-ol (3β,22E) and 9,19-cyclolanost-24-en-3-ol (3β)) were found in this plant only.     

Inhibition of Spore Germination of Phakopsora Pachyrhizi Using Crude Extracts of Amaranthus Spinosus

The effectiveness of methanolic and n-hexane crude extracts of Amaranthus spinosus to inhibit the spore germination of Phakopsora pachyrhizi, a causal agent of soybean rust disease was studied. Both methanolic and n-hexane crude extracts inhibited spore germination at concentrations of 0.1% to 5.0%. Methanolic extract of the roots at a concentration of 2.5% inhibited 55% of spore germination, and this result was similar when higher concentration at 5% of methanolic and n-hexane extracts of the flowers was used. The presence of alkaloids, flavonoids, tannins, saponins, and terpenoids in the extract may be responsible for the inhibition. The extract was potential to be utilized as a botanical fungicide.     

Die Verteilung der Extraktstoffe im Stammholz von Pinus sylvestris L.

Yield and composition of extractives from sapwood and heartwood ofP. sylvestris differ greatly. While neutral lipids dominate in sapwood, free resin and fatty acids are the main constituents in heartwood. The extractive content in heartwood decreases with increasing trunk height. Beside the lipophilic components in the petrol ether extracts, carbonhydrates, low molecular lignin precursors and stilbene phenols (from heartwood only) can be obtained with more polar solvents.     

Antioxidant activity and chemical constituents of essential oil and extracts of Rhizoma Homalomenae

Antioxidant activity and composition of essential oil and extracts of Rhizoma Homalomenae were determined. The extracts, especially the ethyl acetate extract (QJ4 fraction) of the aqueous residue after oil distillation, had considerable antioxidant potency which was significantly associated with their total phenolic and flavonoid contents, but the essential oil showed only weak or moderate activity. GC–MS analysis of the essential oil (yield: 0.82%, v/w) resulted in the identification of 77 compounds, accounting for 96.5% of the content of the oil. The major components, epi-α-cadinol (14.8%), α-cadinol (14.8%), α-terpineol (13.8%), linalool (11.1%), terpinen-4-ol (4.92%), and δ-cadinene (4.91%) constituted 64.3% of it. LC–MS/MS and HPLC analyses showed seven phenolic compounds (protocatechuic acid, vanillic acid, syringic acid, caffeic acid, p-coumaric acid, ferulic acid and apigenin) with a great amount in the ethyl acetate extract (QJ4 fraction). The strong antioxidant properties of the plant extracts may be attributed to the presence of these phenolics.     

Antioxidant activity of brown pigment and extracts from black sesame seed (Sesamum indicum L.)

The antioxidant activities of brown pigment, extract of n-hexane and extract of supercritical carbon dioxide extraction of black sesame seeds were investigated in this study. Kinetics of anti-radical activity showed that the reaction between DPPH and brown pigment of sesame seed was rapid and reached the steady state in 10 min. Extracts from supercritical carbon dioxide extraction and n-hexane extraction reacted with DPPH slowly and the absorbance became stable after 35 min. However, α-tocopherol and trolox were rapid while the kinetic behaviour of BHA was intermediate. The brown pigment of sesame seed also showed a lower EC₅₀ (13.5 μg ml⁻¹) than the other two extracts and α-tocopherol, which was about 7–10 fold of the antioxidant activity of the supercritical carbon dioxide extract and the n-hexane extract. The ferric thiocyanate (FTC) method also showed that the brown pigment of sesame seed provided higher inhibition activity against lipid peroxidation at 200 μg ml⁻¹ than did the supercritical carbon dioxide extract an n-hexane extract at 1 mg ml⁻¹. However, the activities of the supercritical carbon dioxide extract and n-hexane extracts were significantly higher than that of α-tocopherol. In the linoleic acid system, the brown pigment of black sesame seed showed an equal antioxidant activity to BHA and higher than trolox and α-tocopherol. The results indicated that the brown pigment of sesame seed possessed excellent antioxidant activity.     

Screening of bioactive lipids and radical scavenging potential of some solanaceae plants

Gas-liquid chromatography (GLC) and normal-phase high performance liquid chromatography (HPLC) were used to analyse fatty acids and fat-soluble bioactives of the seeds of four Datura species (D. stramonium, D. metel, D. tatula, D. innoxia) and two Hyoscyamus species (H. muticus, H. niger). The amounts of n-hexane extract were found to be between 5.50% and 12.6%. The major fatty acid was linoleic acid followed by oleic, palmitic and stearic acids. The crude n-hexane extract was characterised by a relatively high amount of phytosterols, wherein the sterol markers were stigmasterol, β-sitosterol, lanosterol, Δ5-avenasterol and sitostanol. In all plant extracts γ-tocopherol was the major component present accounting for more than 80% of total tocopherols detected. When different extracts were compared for their radical scavenging activity (RSA) toward the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, D. Innoxia exhibited a stronger RSA.     

Antioxidant and antimicrobial activities of crude sorghum extract

Here, we report the antioxidant and antimicrobial activities of sorghum (Sorghum bicolor Moench) extracts prepared from 25 cultivars from South Korea. Four cultivars of sorghum were extracted with methanol, then further fractioned with n-hexane, ethyl acetate, n-butanol, and water. The RC₅₀ (the concentration of antioxidant required to achieve absorbance equal to 50% that of a control containing no antioxidants) value of the DPPH method and reducing power showed higher efficiency in the BuOH layer of all selected cultivars except Neulsusu. The various fractions were then examined for antimicrobial activity by a serial two fold dilution assays using the paper disc method. The methanol extracts showed higher levels of antimicrobial activity than the other fractions. Our results indicate that sorghum extracts could be used as a source of antioxidant and antimicrobial ingredients in the food industry.     

Radical scavenging capacities and inhibition of human prostate (LNCaP) cell proliferation by Fortunella margarita

Lyophilised nagami kumquat (Fortunella margarita) powder was extracted with five different solvents. Dried extracts of EtOAc and MeOH-water (4:1, v/v) had the highest and lowest total phenolics, respectively, by Folin-Ciocalteu method. LC-MS analysis confirmed the presence of different levels of rutin, narirutin, poncirin, apigenin 8-C-rutinoside and 3′,5′,di-C-β-glucopyranosyl phloretin in all the extracts except n-hexane. EtOAc and MeOH extracts exhibited the highest and the lowest 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, respectively. The order of antioxidant capacity was found to be MeOH-water (4:1, v/v) > EtOAc > MeOH > n-hexane > acetone by phosphomolybdenum complex and oxygen radical absorbance capacity (ORAC) values. Among five extracts, n-hexane extract exhibited the highest inhibition of human prostate cancer (LNCaP) cells (86.4%) after 96 h at 100 μg/mL, followed by EtOAc (82.8%), MeOH (76.7%) and MeOH-water (4:1, v/v) (68.2%). Fragmentation of DNA suggests the ability of extracts to induce apoptosis in LNCaP cells. The cleavage of caspase-3 was the highest in n-hexane and EtOAc extracts, whereas the ratio of Bax/Bcl2 was the highest in MeOH and MeOH-water (4:1, v/v) extracts. The results of the present study were also supported by fluorescent images of LNCaP cells treated with kumquat extracts. The maximum cell proliferation inhibition activity of n-hexane extract may be due to the presence of one or cumulative effect of β-carotene, β-cubebene and hexadecanoic acid. Remaining four extracts exhibited differential antioxidant activity and cytotoxicity which may be due to the presence of various levels of rutin, narirutin, poncirin, apigenin-8-C-rutinoside and 3′,4′-di-C-β-glucopyranosyl phloretin in each extract.     

Two novel glycosyl cinnamic and benzoic acids from korean black raspberry (Rubus coreanus) wine

Korean black raspberry (Rubus coreanus) wine was solvent-fractionated with n-hexane, ethyl acetate, and n-butanol and the n-butanol layer was purified by various column chromatographic procedures, including Amberlite XAD-2, Sephadex LH-20, and octadecylsilane resins as well as high performance liquid chromatography. Two novel glycosyl cinnamic and benzoic acids were isolated and their structures were (E)-8-O-β-d-glucopyranosylcinnamic acid (1) and 3′-[O-β-d-glucopyranosyl)(1″→6′)-α-d-psicofuranosyl] benzoate (2) based on the spectroscopic data obtained by high resolution fast-atom bombardment mass spectroscopy and nuclear magnetic resonance analyses.     

Terpenoids and hexenes from the leaves of Crataegus pinnatifida

Crataegus pinnatifida have long been used in traditional Chinese medicine and European herbal medicine, and are widely consumed as food, in the form of juice, drink, jam and canned fruit. Four new compounds, a sesquiterpene and its glycoside (1–2), two monoterpene glycosides (3–4), together with eight known compounds (5–12), were isolated from the leaves of C. pinnatifida. Their structures were elucidated as (5Z)-6-[5-(2-hydroxypropan-2-yl)-2-methyltetrahydrofuran-2-yl]-3-methylhexa-1,5-dien-3-ol (1), (5Z)-6-[5-(2-O-β-d-glucopyranosyl-propan-2-yl)-2-methyl tetrahydrofuran-2-yl]-3-methylhexa-1,5-dien-3-ol (2), 5-ethenyl-2-[2-O-β-d-glucopyranosyl-(1″ → 6′)-β-d-glucopyranosyl-propan-2-yl]-5-methyltetrahydrofuran-2-ol (3), 4-[4β-O-β-d-xylopyranosyl-(1″ → 6′)-β-d-glucopyranosyl-2,6,6-trimethyl-1-cyclohexen-1-yl]-butan-2-one (4), (Z)-3-hexenyl O-β-d-glucopyranosyl-(1″ → 6′)-β-d-glucopyranoside (5), (Z)-3-hexenyl O-β-d-xylopyranosyl-(1″ → 6′)-β-d-glucopyranoside (6), (Z)-3-hexenyl O-β-d-rhamnopyranosyl-(1″ → 6′)-β-d-glucopyranoside (7), (3R,5S,6S,7E,9S)-megastiman-7-ene-3,5,6,9-tetrol (8), (3R,5S,6S,7E,9S)-megastigman-7-ene-3,5,6,9-tetrol9-O-β-d-glucopyranoside (9), (6S,7E,9R)-6,9-dihydroxy-4,7-megastigmadien-3-one 9-O-[β-d-xylopyranosyl-(1″ → 6′)-β-d-glucopyranoside] (10), Linarionoside C (11), and (3S,9R)-3,9-dihydroxy-megastigman-5-ene 3-O-primeveroside (12), using a combination of mass spectroscopy, 1D and 2D NMR spectroscopy and chemical analysis. Cytotoxicity of the new compounds was assayed against selected human glioma (U87) cell lines.     

Antioxidant and antifungal activities of extracts from 15 selected hardwood species of Malaysian timber

The antioxidant activities, total phenols and antifungal activities of 35 extracts samples from 15 species of Malaysian timber were investigated. The methanol extracts from Mangifera indica heartwood were found to have superior antioxidant activity with an EC₅₀ value of 4.71±0.89 μg/ml. Antioxidant activities correlated with total phenols contents. The methanol extracts from Neobalanocarpus heimii bark and Cinnamomum porrectum heartwood showed moderate antifungal activity against a brown-rot fungus, Gloeophyllum trabeum. The methanol extracts from Neobalanocarpus heimii bark and Endospermum malaccense inner wood showed the highest antifungal activity against a white-rot fungus, Pycnoporus sanguineus, at a minimum effective amount of 100 μg. The activities of these extracts were equal to the activity of the positive control, glycyrrhizic acid dipotassium salt, suggesting that they have great potential as a source of fungistats.     

Insecticidal and antifeedant activities of medicinal plant extracts against Attagenus unicolor japonicus (Coleoptera: Dermestidae)

Methanol extracts from 28 medicinal plant species were tested for their insecticidal and antifeedant activities against Attagenus unicolor japonicus larvae by using a fabric-piece bioassay. Responses varied according to plant species, dose, and exposure time. Methanol extract of Allium sativum bulb gave 93% mortality at 5.2 mg/cm² 7 days after treatment (DAT). Eugenia caryophyllata bud extract produced 100% mortality at 2.6 mg/cm² 14 DAT and 90% mortality at 1.3 mg/cm² 21 DAT. Foeniculum vulgare fruit extract gave 67% and 100% mortality at 5.2 mg/cm² 21 and 28 DAT, respectively. Methanol extracts of Angelica dahurica root, Lysimachia davurica whole plant, and Nardostachys chinensis rhizome exhibited complete antifeedant activity at 1.3 mg/cm² over a 30-day period. The plant extracts described merit further study as potential insecticidal or antifeedant agents against A. unicolor japonicus.     

Evaluation of antioxidant ability of ethanolic extract from dill (Anethum graveolens L.) flower

Antioxidant activities of ethanolic extract from dill flower and its various fractions were evaluated with 2,2-diphenyl-1-picrylhydrazyl radical scavenging, Trolox equivalent antioxidant capacity, reducing power, chelating power, and β-carotene bleaching assays. The flower extract was successively separated into n-hexane, ethyl acetate and ethanol soluble fractions by liquid–liquid partition. Dill leaf and seed extracts were used for comparison. In all assays, the flower extract showed higher antioxidant activity than the leaf and seed extracts. With regard to various fractions of the flower extract, the sequence for antioxidant activity was ethyl acetate fraction > ethanol fraction > original flower extract > n-hexane fraction. Phenols including flavonoids and proanthocyanidins should be responsible for antioxidant abilities of the flower extract. Chlorogenic acid, myricetin, and 3,3’,4′,5,7-pentahydoxyflavan (4 → 8)-3,3′,4′,5,7-pentahydoxyflavan were the major phenolic acid, flavonoid, and proanthocyanidin, respectively, in the dill flower extract.     

Antioxidant activity and contents of essential oil and phenolic compounds in flowers and seeds of Alpinia zerumbet (Pers.) B.L. Burtt. & R.M. Sm

Alpinia zerumbet leaves and rhizomes have been extensively studied for their chemical compositions and biological activities. However, less attention has been given to its flowers and seeds. In our study, essential oil, total phenolics and antioxidant capacities assayed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching methods were evaluated in flowers and seeds of A. zerumbet. In addition, their phenolic composition was determined by GC–MS and HPLC. 1,8-Cineol, camphor, methyl cinnamate and borneol were the major constituents in flower oils, whereas the main components in seeds oil were α-cadinol, T-muurolol, α-terpineol, δ-cadinene and terpinene-4-ol. The results showed that the hexane extract of flowers contained a significantly higher quantity of dihydro-5,6-dehydrokawain (DDK) than that of seeds. Total phenolic contents of flower and seed extracts were measured as 56.7 and 13.7 mg gallic acid equivalent per gram extract, respectively. The ethyl acetate extract of flowers and seeds possessed a high antiradical activity and prevented the bleaching of β-carotene. The HPLC analysis indicated that p-hydroxybenzoic acid, ferulic acid and syringic acid were the predominant phenolics in the ethyl acetate extract of flowers, whilst p-hydroxybenzoic acid, syringic acid and vanillin were the major phenolics in seeds.     

Volatile constituents from the leaves of Polygonum cuspidatum S. et Z. and their anti-bacterial activities

Volatile substances extracted from leaves of Polygonum cuspidatum S. et Z. by simultaneous steam distillation and solvent extraction (SDE) were investigated in terms of their inhibitory activities against six foodborne micro-organisms using Bioscreen C. The SDE extracts from P. cuspidatum S. et Z. obtained after 1.5 or 2.0 h at pH 4.5 exhibited strong growth inhibition upon the six micro-organisms tested; their volatile contents were 5.74 and 8.89 μl/100 g, respectively. Anti-bacterial activities against the bacterial strains examined increased upon reducing SDE pH from 6.5 to 3.5 and by increasing the extraction time from 0.5 to 2.0 h. The major volatile components of the SDE extracts obtained after 1.5 h at pH 4.5 were 2-hexenal (73.36%), 3-hexen-1-ol (6.97%), n-hexanal (2.81%), 1-penten-3-ol (2.55%), 2-penten-1-ol (2.21%), and ethyl vinyl ketone (1.13%) by Gas chromatography. The addition of 10% (v/v) of the SDE extracts to broth completely inhibited the growth of Bacillus cereus and of Vibrio parahaemolyticus for 72 h.     

Phenolic composition and biological activities of Salvia halophila and Salvia virgata from Turkey

The aerial parts of Salvia halophila and Salvia virgata were subjected to Soxhlet extraction with different solvents such as n-hexane, ethyl acetate, methanol, and aqueous methanol (50%). Plants were also extracted with water under reflux. The effects of the extracts were studied in p-benzoquinone-induced abdominal constriction test for the assessment of antinociceptive activity and carrageenan-induced hind paw edema and 12-O-tetradecanoyl-13-acetate (TPA)-induced ear edema models in mice for the anti-inflammatory activity. The extracts were analysed using a HPLC–PDA method. Results showed that methanol extract of S. virgata significantly inhibited carrageenan-induced paw edema and p-benzoquinone-induced abdominal constriction at 100 mg/kg dose, while it showed no effect in the TPA-induced ear edema. On the other hand, the other extracts did not show any inhibitory antinociceptive and anti-inflammatory activities in these in vivo models. Rosmarinic acid was found as main constituent in the extracts, while caffeic acid and luteolin derivatives were also detected.     

Phytochemical Characterization of Phagnalon graecum Boiss. by HPLC and GC-MS with its Enzyme Inhibitory and Antioxidant Activity Profiling by Spectrophotometric Methods

In the current study, the n-hexane, chloroform, ethyl acetate, methanol, and water extracts of Phagnalon graecum Boiss. (Asteraceae), a spice plant, were investigated for their enzyme inhibitory activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase, tyrosinase, and antioxidant activities. Antioxidant activity of the extracts was determined by 2,2-diphenyl-1-picrylhydrazyl radical scavenging, ferric ion-chelation activity, and ferric-reducing antioxidant power tests. Total phenol (gallic acid equivalent) and flavonoid (quercetin equivalent) contents were calculated. Essential oil of the plant was analyzed by GC-MS, while the selected phenolic acids were analyzed by HPLC. The extracts had insignificant inhibition against the tested enzymes, whereas they displayed a remarkable antioxidant activity. Therefore, to the best of our knowledge, this study presents the first data on biological activity and phytochemical content of P. graecum and this species could be utilized as potential antioxidant applicable for food preservation.     

Pressurised solvent extraction of policosanol from wheat straw,germ and bran

Policosanols (PCs) are a group of long chain aliphatic alcohols that have been reported to have low-density lipoprotein (LDL) cholesterol-lowering properties. Wheat is a good source of these compounds. This study examined the effect of solvent type and temperature on extract yields and PC content and composition in the extracts. Wheat germ, straw and bran samples were extracted with petroleum ether, chloroform, n-hexane and ethanol at various temperatures ranging from 80 to 125 °C.     

Study on antioxidant activity of certain plants in Thailand: Mechanism of antioxidant action of guava leaf extract

The ethanol extracts from 24 samples plant species commonly found in Thailand were investigated and compared on their antioxidant activity by ABTS assay. The ethanol extract from the leaves of guava (Psidium guajava) showed the highest antioxidant capacity with the TEAC value of 4.908 ± 0.050 mM/mg, followed by the fruit peels of rambutan (Nephelium lappaceum) and mangosteen (Garcinia mangostana) with the TEAC values of 3.074 ± 0.003 and 3.001 ± 0.016 mM/mg, respectively. The further investigation of guava leaf extracts from different solvents; n-hexane, ethyl acetate, n-butanol, and methanol, was examined using ABTS and FRAP assays. The total phenolic content was done by Folin–Ciocalteu reaction. The results indicated that the methanol fraction possessed the highest antioxidant activity, followed by the butanol and ethyl acetate fractions, respectively. The hexane fraction showed the lowest antioxidant activity. The results demonstrated that the mechanism of antioxidant action of guava leaf extracts was free radical scavenging and reducing of oxidized intermediates. The phenolic content in guava leaf fraction played a significant role on the antioxidant activity via reducing mechanisms.