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Carpobrotus edulis (L.) N.E.Br. (Hottentot-fig) is a problematic invasive species found in coastal areas worldwide. Mechanical removal is a common control method, leaving the removed biomass available as a possible source of natural phytochemicals with prospective commercial applications. While the Hottentot-fig's vegetative organs have been studied previously, this work establishes for the first time a seasonal and spatial comparative analysis of its nutritional, chemical, and bioactivity profiles (in three locations over four seasons). Proximate and mineral contents were assessed, along with its phenolic composition and in vitro antioxidant and anti-inflammatory properties. Hottentot-fig's biomass offered a good supply of nutrients, mainly carbohydrates, proteins, and minerals, with a tendency for higher concentrations of the most relevant minerals and proteins in autumn and winter, and in plants from sites A (Ria de Alvor lagoon) and B (Ancão beach). The extracts were rich in polyphenolics, with higher levels in spring and summer, especially for luteolin-7- O -glucoside and salicylic and coumaric acids. The extracts were also effective antioxidants, with stronger radical scavenging activities in spring and summer, along with anti-inflammatory properties. Our results suggest that the usually discarded plant material of this invasive halophyte could be valuable as a source of natural products with potential biotechnological applications in the food and nutraceutical industries.

This work reports for the first time the in vitro anti-oxidant (towards DPPH, ABTS, copper and iron), enzymatic inhibitory (on AChE, BuChE, α-glucosidase, α-amylase and tyrosinase), cytotoxicity (towards HepG2 and HEK 293 cells), and metabolomics (by HPLC-MS) of extracts from organs of Malcolmia littorea (L.) R.Br. Extracts were constituted mainly by phenolic acids and flavonoids, and main compounds were salicylic acid and luteolin-7-O-glucoside. Samples showed reduced radical scavenging and metal chelating capacity, and only the methanol extracts reduced iron. The root's ethanol and methanol extracts, and the aerial organ's ethanol extract exhibited the highest AChE inhibition. The root's ethanol extract displayed dual anti-cholinesterase activity. Samples showed a low capacity to inhibit α-amylase, but a high α-glucosidase inhibition was obtained with the root's and flower's ethanol extracts, and flower's methanol extract. Overall, samples displayed a high inhibition against tyrosinase, reduced HepG2 cellular viability and were less toxic towards HEK 293 cells.

Aromatic halophyte plants are an outstanding source of bioactive compounds and natural products with potential use in the food industry. This work reports the in vitro antioxidant activity, toxicity, polyphenolic profile and mineral contents of infusions and decoctions from stems, leaves and flowers of Crithmum maritimum L., an aromatic and edible maritime halophyte (sea fennel). Aspalathus linearis (Burm.f.) Dahlg. (rooibos) herbal tea was used as a reference. Sea fennel's tisanes, particularly from leaves, were rich in phenolic compounds and five of them (p-hydroxybenzoic and ferulic acids, epicatechin, pyrocatechol and 4-hydroxybenzaldehyde) were here described in C. maritimum for the first time. Chlorogenic acid was the dominant phenolic determined. Na was the most abundant mineral in all tisanes followed by Ca and Mg in leaves' tisanes and K in flowers. Sea fennel's samples had a similar antioxidant activity than those from A. linearis, and had no significant toxicity towards four different mammalian cell lines. Altogether, our results suggest that sea fennel can be a source of products and/or molecules for the food industry with antioxidant properties and minerals in the form, for example, of innovative health-promoting herbal beverages., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This work reports the in vitro antioxidant and anti-inflammatory activities and toxicity of infusions and decoctions of Limonium algarvense flowers, and green tea. The total contents in different phenolic groups and the quantification of individual phenolics by HPLC are also reported. L. algarvense and green tea had similar antioxidant properties, except for hydroxyl radical-scavenging activity, higher on green tea, and iron chelating potential, higher on L. algarvense. The later species also had the uppermost anti-inflammatory potential. Green tea decoction had the highest content of phenolic groups, but the infusion of L. algarvense had higher amounts of salicylic, gallic and coumaric acids. L. algarvense was not toxic, whereas green tea was toxic for S17 cells. Under our experimental conditions, infusions and decoctions of L. algarvense flowers had similar or higher antioxidant and anti-inflammatory properties than green tea, and thus, may be useful for alleviating symptoms associated with oxidative and inflammatory-related diseases., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This work reports the in vitro inhibitory activity of water decoctions of leaves, germ flour, pulp, locust bean gum and stem bark of carob tree on α-amylase, α-glucosidase, acetylcholinesterase and butyrylcholinesterase. The antioxidant activity and the chemical characterisation of the extracts made by spectrophotometric assays and by high-performance liquid chromatography are also reported. Leaves and stem bark decoctions strongly inhibited all the enzymes tested, had significant antioxidant activity and the highest total phenolics content. The major compounds were identified as gallic acid in the leaves and gentisic acid in the stem bark.

Background: This study aimed to evaluate the antioxidant and antimicrobial activity of extracts (aqueous, ethanolic and essential oil) from Satureja montana and to characterise the chemical composition of its essential oil., Results: Satureja montana L. essential oil had relatively high antimicrobial activities against the seven species of bacteria tested. In contrast, aqueous extracts did not reveal antibacterial activity, and the ethanol extract was not effective against Salmonella typhimurium. The major volatile constituents of the essential oil were carvacrol (306 g L(-1)), thymol (141 g L(-1)), and carvacrol methyl ether (63 g L(-1)). The strongest antioxidant capacity was obtained with the hot water extracts of S. montana, whereas the plant essential oil revealed the highest phenolic content., Conclusion: The findings indicate that the bioactive extracts of S. montana have strong potential for use as natural antimicrobials and antioxidants in the preservation of processed food., (Copyright © 2011 Society of Chemical Industry.)

This work aimed to evaluate the phytochemical content and to determine the antioxidant and cytotoxic activities of methanol extracts of the carob tree (Ceratonia siliqua L.) germ flour. The extracts were rich in phenolic compounds, had considerable antioxidant activity, and reduced the viability of cervical (HeLa) cancer cells. The chemical content and the biological activities of the extracts were significantly affected by gender and cultivar. Female cultivar Galhosa had the highest levels of phenolic compounds, and the highest antioxidant activity. Extracts from the hermaphrodite trees and from the female cultivars Galhosa and Costela/Canela exhibited the highest cytotoxic activity. The most abundant compound was theophylline. The phenolic content was correlated to both antioxidant and cytotoxic activities. Our findings provide new knowledge about the health implications of consuming food supplemented with carob germ flour.

Bran of different rice cultivars produced in Portugal were used to study supercritical carbon dioxide extraction conditions of rice bran oil (RBO) and evaluate and compare antioxidant activity and fatty acid composition of the different rice bran varieties. The effect of plant loading (10-20 g), CO2 flow rate (0.5-1.5 L/min), pressure (20-60 MPa), and temperature (40-80 °C) was studied. The amount of oil extracted ranged from 11.72%, for Ariete cultivar, to 15.60%, for Sirio cultivar. The main fatty acids components obtained were palmitic (13.37%-16.32%), oleic (44.60%-52.56%), and linoleic (29.90%-38.51%). Excellent parameters of the susceptibility to oxidation of the oils were obtained and compare. RBO of Ariete and Gladio varieties presented superior DPPH and ABTS radical scavenging activities, whereas, Minima, Ellebi, and Sirio varieties had the lowest scavenging activities. Moreover, the oil obtained towards the final stages of extraction presented increased antioxidant activity. [ABSTRACT FROM AUTHOR]

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 μg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and ß-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value. [ABSTRACT FROM AUTHOR]

Acetylcholinesterase inhibition, antioxidant and cytotoxic activities of Hedychium gardnerianum leaf essential oils from S. Miguel Island were determined. All the oils inhibited acetylcholinesterase, with IC50 values of approximately 1 mg/mL, showing no statistical differences between collection sites. Three oils presented mixed inhibition, whilst one was almost truly competitive. This activity can be attributed to the presence of sesquiterpenes, which constituted more than 60% of the composition of the oils. Regarding the antioxidant activity as measured by the DPPH method, all the oils presented activities similar to reference compounds, although with statistical differences between collection sites. Cytotoxicity measured using Artemia salina classified these oils as moderately toxic, with LC50 values ranging from 300 to 500 μg/mL. These results indicate a possible application of these oils in aromatherapy as coadjuvants in the treatment of cognitive diseases such as Alzheimer, since they may contribute to increase acetylcholine in cholinergic neurons and simultaneously fight deleterious oxidations responsible by neurological degeneration. [ABSTRACT FROM AUTHOR]

Abstract: The phenolic profile and the antioxidant activity of Rocha pear, a Portuguese pear cultivar, were determined and compared with the commercially available pear varieties Comice, Abate, General Leclerc and Passe Crassane. Phenolic composition of the methanolic extracts of these pears was determined by high performance liquid chromatography with diode array detection (HPLC-DAD), while antioxidant activities were evaluated using three complementary test systems: DPPH radical scavenging activity, ferric reducing power capacity and β-carotene/linoleic acid bleaching assay. When compared to the studied varieties, Rocha pear (peel and flesh) presented the highest content of total phenolics. Among them, chlorogenic, syringic, ferulic and coumaric acids, arbutin and (−)-epicatechin were detected as major components. In addition, among the tested varieties, Rocha pear presented the best antioxidant activities in the DPPH and ferric reducing power assays. [Copyright &y& Elsevier]

Ballota macrodonta Boiss. et Balansa., is a traditionally used endemic medicinal plant used to manage a plethora of diseases in Turkey. Nonetheless, few studies have endeavoured to highlight its therapeutic potential and its phytochemical profile. We hypothesized that B. macrodonta would possess multi-pharmacological propensities and bioactive compounds that would justify its use as a folk remedy. Aerial part of B. macrodonta was assessed for its antioxidant, antimicrobial, and enzymatic inhibitory potential using different extraction solvents. The total bioactive components determination and compound identification using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) method were used to correlate the biological properties. HPLC-DAD profile showed the presence of 19 components (e.g. hydroxybenzoic acid, catechin hydrate, vanillic acid, caffeic acid, syringic acid, epicatechin, coumaric acid, ferulic acid, luteolin-7- O -glucoside, rutin, and quercetin). The water and methanolic extracts showed high total phenolic and flavonoid contents, respectively. The overall antioxidant capacity of the water extract was higher than the one of the methanol extract. The extracts showed inhibitory activity against cholinesterases, tyrosinase, α-amylase and α-glucosidase. The extracts also presented antimicrobial activity against eight Gram positive/negative bacteria (MIC – 0.05–0.15 mg/mL) and eight fungi (MIC – 0.0125–0.20 mg/mL). The presence of active biomolecules with multi-pharmacological properties makes B. macrodonta a potential source of health-promoting compounds that can be exploited as a novel medicinal herbal product. [ABSTRACT FROM AUTHOR]

Natural antioxidants as nutritional supplements have gained increasing importance over the last years, due to their general lower toxicity and side effects. Halophyte plants are considered an important reservoir of bioactive molecules with multiple biotechnological applications, including antioxidant. This study reports for the first time the antioxidant activity and the phenolic composition of methanol extracts of different anatomical parts of Limonium algarvense Erben, an endemic halophyte species of the Southwest area of the Iberian Peninsula. Antioxidant activity was determined by different assay systems, namely radical scavenging activity (RSA) on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals and on nitric oxide (NO), ferric reducing antioxidant power (FRAP), and metal chelating activity on iron and copper. The total phenolics, flavonoids, tannins, hydroxycinnamic acids, anthocyanins, flavones and flavonols are also reported, along with the phenolic composition determined by High Performance Liquid Chromatography (HPLC). In general flowers had the highest antioxidant activity, coupled with the highest levels of phenolics. Gallic acid (GA) and catechin were the main component in flowers, roots, and peduncles and in leaves there was a dominance of epigallocatechin gallate and GA. Our results suggest that L. algarvense, particularly its flowers, is a promising source of bioactive antioxidants with potential applications in several fields, such as the agro-food industry, namely as functional beverage. [ABSTRACT FROM AUTHOR]

This work reports the in vitro antioxidant and inhibitory activities of hexane, methanol and water extracts of cork oak ( Quercus suber ) against acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), α-amylase and α-glucosidase. The total content of phenolics (TPC), tannins (TTC) and flavonoids (TFC), and the HPLC profile of the main phenolic compounds present in the extracts, were also determined. In the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay the best results were obtained with the methanol and water extracts from both leaves and acorns (41–49%). In the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method the highest activity was observed with the methanol and leaf water extracts (63–71%). The most significant effects on cholinesterase activity were obtained with the methanol leaf extract at the concentration of 1 mg/mL, yielding inhibition values of 79 and 80% on AChE and BuChE, respectively. No relevant activity was detected against α-amylase, but samples significantly inhibited α-glucosidase from baker's yeast, and the best results were obtained with the water and methanol leaf extracts with values of 97 and 89%, respectively, higher than the positive controls used (acarbose and glucobay). The methanol leaf extract had the highest TPC (211 mg GAE/g, DW) and TFC (8.2 mg RE/g, DW), whereas the water extracts had the highest tannin levels (87 CE/g, DW). The main compound in the methanol leaf extract was gentisic acid (24.3 mg/g, DW). Our results suggest that leaves and acorns from cork oak contain compounds useful for alleviating symptoms associated with Alzheimer disease and other neurodegenerative ailments as well as diabetes. [ABSTRACT FROM AUTHOR]

Methanol (ME) and hot water extracts (WE) of carob tree sapwood (Ceratonia siliqua L.) exhibited high antioxidant activity and were rich in phenolic compounds, with the main compounds identified by HPLC/DAD as gentisic acid and (-)-epicatechin. The ME displayed a high in vitro antitumor activity against human tumoural cell lines and reduced intracellular ROS production by HeLa cells after treatment with H2O2. (-)-Epicatechin was shown to contribute to the cytotoxic activity of the ME. This is the first report on the biological activity of carob tree sapwood. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to determine the effectiveness of 17 essential oils to inhibit the growth of seven food-borne spoilage and pathogenic bacterial strains (Brochothrix thermosphacta, Escherichia coli, Listeria innocua, Listeria monocytogenes, Pseudomonas putida, Salmonella typhimurium and Shewanella putrefaciens). Additionally, the antioxidant activity (by free radical scavenging activity and ferric reducing power) and the chemical composition of these essential oils were evaluated. All essential oils inhibited the growth of at least four bacteria tested, and lower values of minimum inhibitory concentration (<3.0mgmL−1) were needed to inhibit P. putida. The highest reductions (8.0logCFUmL−1) were achieved with coriander, origanum and rosemary essential oils for L. innocua, as well as with thyme essential oil for both Listeria strains. The results showed that for the evaluation of antibacterial activity of plant essential oils, bacterial counts should be performed instead of absorbance readings when using microdilution methods. Regarding the antioxidant activity, clove and origanum essential oils showed the strongest antioxidant properties. Essential oils showed a great variety of compounds in their chemical compositions, some of those with known antibacterial and antioxidant properties. In conclusion, all tested essential oils have very strong potential applicability as antibacterial and antioxidant agents for food and pharmaceutical industries. [Copyright &y& Elsevier]

Abstract: Salvia sclareoides is an aromatic herb native to Portugal, of which phenolic content (Folin–Ciocalteau method), chemical profile (HPLC/DAD), antioxidant activity (DPPH, β-carotene/linoleic acid assays), acute toxicity (MTT method, adapted for non-adherent cells), genotoxicity (short-term chromosomal aberration assay) and prion binding properties were evaluated in the acetone, water, ethanol, methanol and n-butanol extracts. The latter presented the highest phenolic content and antioxidant activity (DPPH assay), and was the single one with the flavonoids (+)-catechin, kaempferol O-glucoside and quercetin. Vanillic acid was the major component of all extracts but gallic, gentisic, caffeic, syringic, coumaric and ferulic acids were also found in some extracts. Only the n-butanol extract had components binding to the cellular form of human prion protein detected by NMR which showed specificity for two regions of the folded domain and for the unstructured N-terminal region. Extracts were not cytotoxic nor genotoxic, reinforcing the potential of S. sclareoides for nutraceutical purposes. [Copyright &y& Elsevier]

Abstract: There is a growing interest of industry to replace synthetic chemicals by natural products with bioactive properties from plant origin. The aim of this study was to determine the chemical composition of European pennyroyal (Mentha pulegium) essential oil and to characterize the in vitro antioxidant and antimicrobial activities of its water (hot and cold) and ethanolic extracts and of the essential oil. The essential oil revealed menthone, pulegone and neo-menthol as the main constituents, comprising 35.9, 23.2 and 9.2% of the essential oil, respectively. The hot water extract exhibited the highest antioxidant activity and phenol content. In contrast, the extracts were not very effective to inhibit the growth of the seven foodborne spoilage and pathogenic bacteria tested, but the essential oil showed antibacterial activity against all bacterial strains. In conclusion, extracts and essential oil of M. pulegium from Mediterranean origin have huge potential as an alternative to chemical additives for the food industry. [Copyright &y& Elsevier]