Faunal differences between the invasive brown macroalga Sargassum muticum and competing native macroalgae

Interactions between macroalgae and their associated fauna are of great interest for marine invasions, because fauna may increase the biotic resistance of a system and macroalgal invasions may cause shifts in faunal composition. We tested for differences in faunal community structure between a macroalgal invader, Sargassum muticum, and several native macroalgae in intertidal pools on both the west and south coast of Portugal. On each coast, we compared the faunal diversity and composition associated with the invader with that of the competing native macroalga(e). On the west coast, the diversity of the fauna associated with S. muticum was equal to or lower than with the native competitor, Cystoseira humilis. Fauna composition differed between S. muticum and C. humilis at both locations, but within each species, no differences between locations were detected. In contrast, the fauna diversity on S. muticum of the south coast varied among locations. S. muticum fauna differed from the fauna of all native macroalgae at one location, but only from three out of seven native macroalgae at the other location. Discriminating fauna species did not show a consistent pattern towards higher or lower abundances in S. muticum compared to most native macroalgae, and species-specific contributions were small. Differences in fauna community also depended on the identity of the native macroalga. In conclusion, the fauna associated with S. muticum differs from many native brown macroalgae, but these differences were not consistent as they depend both on the native macroalgal species and on location. This invader does not seem to have a severe negative impact on local macroalgae-associated fauna.     

Fractionation of Phenolic Compounds Extracted from Propolis and Their Activity in the Yeast Saccharomyces cerevisiae

We have here investigated the activities of Slovenian propolis extracts in the yeast Saccharomyces cerevisiae, and identified the phenolic compounds that appear to contribute to these activities. We correlated changes in intracellular oxidation and cellular metabolic energy in these yeasts with the individual fractions of the propolis extracts obtained following solid-phase extraction. The most effective fraction was further investigated according to its phenolic compounds.     

Comparison of antifouling properties of native and invasive Sargassum (Fucales,Phaeophyceae) species

The invasiveness of algal species can be facilitated by chemo-ecological traits that allow the establishment of invasive species in a highly competitive environment. Anti-bacterial, anti-quorum sensing, anti-diatom and anti-larval properties of the invasive brown macroalga Sargassum muticum and three native Sargassum species from Oman waters were compared in laboratory and field experiments to assess whether these traits have the potential to facilitate the invasion process. Only the extract of S. muticum inhibited bacterial growth of four marine bacterial strains and quorum sensing in the reporter strain Chromobacterium violaceum CV017. Settlement, growth and survival of the diatom Cylindrotheca closterium and larvae of the bryozoan Bugula neritina were significantly inhibited by all Sargassum extracts in laboratory experiments. However, crude extracts of S. muticum had the strongest antifouling effect. Natural tissue-level concentrations of S. muticum extract reduced diatom density to about 20% compared with the controls. Larval mortality increased by 80–90% compared with controls with S. muticum extract diluted to one-third natural levels. Significant anti-diatom activity of S. muticum was confirmed in the field experiments with Sargassum extracts embedded in a phytagel matrix. Comparison of non-polar compounds by gas chromatography–mass spectrometry demonstrated that S. muticum extracts had overall fewer secondary metabolites but more species-unique compounds than extracts of native Sargassum spp. The greater antifouling defence of invasive vs. native Sargassum species indicates a selective trait that may contribute to the invasion success of S. muticum.     

Antioxidant properties and total phenolic contents of some tropical seaweeds of the Brazilian coast

Many types of macroalgae contain a wide range of bioactive compounds that have antioxidant potential. However, in contrast to terrestrial plants, only a few studies have reported the antioxidant activity of seaweeds. Therefore, extracts from 26 marine macroalgae species from the south and southeast coasts of Brazil were evaluated for their antioxidant activity, using the 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) method and β-carotene/linoleic acid assay, and their total phenolic contents, through Folin–Ciocalteu method. Padina gymnospora, Sargassum vulgare, and Osmundaria obtusiloba presented the highest values of total phenolic content. Using β-carotene bleaching assay, Colpomenia sinuosa, Dictyota sp., Dichotomaria marginata, Ganonema farinosum, and Spyridia clavata presented up to 65 % of antioxidant activity. Some of the extracts showed more than 60 % of inhibition of DPPH in the lowest concentration (0.01 mg/mL), including Amansia sp., Bostrychia tenella, Cryptonemia seminervis, Hypnea musciformis, Plocamium brasiliense (1), and S. clavata. Both Amansia sp., and C. seminervis presented the most relevant antioxidant potential, with percentage of inhibition greater than 70 % in the three tested concentrations. These two species were then analyzed by nuclear magnetic resonance spectroscopy (NMR) and were selected for guided fractionation bioassay. They both presented lipid compounds, fatty acids, esters of fatty acids, triglycerides, and sterols as major components. The fractionation of extracts revealed that the organic fractions were responsible for the antioxidant activity. The results obtained through this work indicate that the analyzed seaweeds are a promising source of compounds with high antioxidant potential.     

Potential of natural phenolic antioxidant compounds from Bersama abyssinica (Meliathacea) for treatment of chronic diseases

Chronic diseases including cardiovascular, diabetes and cancer persist for a long time in the course of treatment affecting health and are currently the cause of many deaths. In most cases, the treatment of chronic infectious diseases especially Tuberculosis relies on conventional drugs which are currently becoming fruitless due to drug resistance and unpredicted complications in course of treatment. However, herbal medicines have for a long time been used in prevention and treatment of chronic diseases including asthma and heart diseases in Africa. In this study, we extracted metabolites and screened for active compounds with potential free radical scavenging and pharmacological activities from Bersama abyssinica, the plant commonly used in traditional medicine in Tanzania. B. abyssinica root, stembark and leaf were air dried, sequentially extracted in various solvents including petroleum ether, dichloromethane, ethylacetate and methanol to yield extracts and fractions. The extracts and fractions were tested for the presence of several metabolites and antioxidant activity. The analysis of chemical compounds from resultant extracts was done by GC–MS for non-polar factions and LC-MS/MC for moderate polar extracts.High amount of phenolic acid, flavonoids and tannin were identified in ethylacetate fraction compared to ethanol, dichloromethane and petroleum ether. The GC–MS analysis of petroleum ether extract of B. abyssinica stem back yielded twelve (12) compounds with varying composition. The most abundant compounds were 2-Butenoic acid, 3-methyl-, ethyl ester comprising 33.8%, n-Hexadecanoic acid comprising 16.7% and Ethanolpentamethyl- yielded in 16.7%.The LC-MS/MS analysis of Ethyl acetate fractions yielded 20 compounds including; Mangiferin and Isoquercitin were abundant in leaves, stembark and roots. Lastly, ethyl vanillate was identified in both roots and leaves whereas Quercitrin and 7,8-Dimethoxycoumarin were found in stembark and root.These findings indicated that B. abyssinica is rich in phenolic compounds ranging from phenolic acids, flavonoids and coumarin that possess high antioxidant and pharmacological properties potential for treatment of chronic diseases.     

Bioactive compounds determination in the callus and hydroalcoholic extracts from Salvia miltiorrhiza and Salvia przewalskii – Preliminary study on their anti-alcoholic activity effects

Studies on hairy roots and callus cultures of Salvia miltiorrhiza and Salvia przewalskii showed that the polysaccharide fraction of yeast extract efficiently stimulated the production of tanshinones in elicited tissues. The aim of our studies was to obtain the biomass of both species enriched in active compounds and to determine tanshinones and phenolic compounds in raw material (callus) and the extracts. Moreover, anti-alcoholic activities of the extracts were tested on one of animal models of alcoholism. It was found that the two Salvia species differed in content of some active compounds. In the hydroalcoholic extracts, an increased content of some compounds was revealed in comparison with the calluses. Only the extract from the S. przewalskii callus (but not from S. miltiorrhiza) reduced significantly an alcohol intake in alcohol-dependent animals, which was correlated with the content of tanshinones (cryptotanshinone, in particular) in the S. przewalskii callus extract, but not with phenolic acids.     

Microwave hydrodiffusion and gravity processing of Sargassum muticum

An aqueous based extraction process was developed to obtain soluble fractions from Sargassum muticum. Microwave hydrodiffusion and gravity (MHG) and subsequent rehydration and extraction stages (MHG-W) in an open system, hot pressurized water extraction or autohydrolysis (A) and enzyme aided extraction (E) were selected on the basis of their simplicity and the possibility of using water as solvent. The performance of these combined technologies using biorenewable solvents to extract antioxidants was compared. A preliminary selection of MHG extraction conditions suggested that 600 W was the optimal irradiation power. A multistage process based on an initial solvent free MHG stage followed by a sequence of water extraction stages (MHG-W) proved suited to selectively obtain phenolic compounds in shorter times than conventional processes. The yield of total solubles was lower than with conventional solvent extraction, but the phenolic content of the extracts and their ABTS radical scavenging properties were enhanced. The microscopic observations of extracted tissues confirmed the impact of the microwave and hot pressurized water processes on the algal cell wall integrity.     

Profiling and Elucidation of the Phenolic Compounds in the Aerial Parts of Gynura bicolor and G. divaricata Collected from Different Chinese Origins

Gynura bicolor and G. divaricata are not only known to be nutritive as cultured vegetables, but also beneficial as folk medicines in East Asia. As demonstrated by the current phytochemical knowledge, the genus Gynura is a promising source of phenolics with multiple medicinal activities. To expand this phytochemical knowledge, the phenolic secondary metabolites of G. bicolor and G. divaricata were studied. From the aerial parts of these two species, collected in five different Chinese locations, two fractions of phenolic compounds with different polarity were obtained by extraction and chromatographic separation. Using UPLC/MS/MS analysis, a total of 53 phenolics were either identified by comparison with respective reference compounds or tentatively characterized by their chromatographic behavior, UV‐absorption patterns, and MS fragmentations. Some naturally existing positional isomers of O‐caffeoylquinic acid, O‐p‐coumaroylquinic acid, O‐feruloylquinic acid, and dicaffeoylquinic acid as well as their methyl esters were qualitatively characterized by their specific fragmentation patterns in targeted MS/MS. In addition, the aerial parts of the two Gynura species contained kaempferol, quercetin oligoglycosides, and a variety of derivatives of benzoic acid, hydroxycinnamic acid, and caffeic acid. Furthermore, the distribution of phenolic compounds in the two species from different Chinese origins was discussed. Finally, an investigation of the total phenolic content and in vitro antioxidant activity of the various phenolic fractions was completed, to evaluate the potential of the extracts of these species for medicinal development. The free‐radical‐scavenging activities of the extracts derived from plants originating from Nanjing were proven to be higher than those of the other extracts, which correlated well with their total phenolic content.     

Chemical composition and biological properties of Synedrella nodiflora (L.) Gaertn: A comparative investigation of different extraction methods

Synedrella nodiflora (L.) Gaertn. (Asteraceae), is a weed with ethnomedicinal uses. To extend scientific information on this species, we evaluated the effects of different extraction procedures (maceration, Soxhlet, sonication and homogenizer-assisted extraction (HAE)) using methanol as solvent, on the chemical composition and biological potential. The chemical profiles of the extracts were identified using a chromatographic (UHPLC-HRMS) technique. The antioxidant and enzyme inhibitory activities of the studied extracts were determined. The extract obtained by Soxhlet technique showed a higher level of total phenolic (TPC) and flavonoid content (TFC) and was a superior source of antioxidant compounds. The macerated extract was the most potent inhibitor of cholinesterases and α-glucosidase, whereas the highest activity against tyrosinase was observed in the order of sonication > Soxhlet > HAE > maceration. A modest activity was observed against α-amylase for all the extracts. Multivariate analysis showed that the bioactive compounds recovery and the biological activities of S. nodiflora were mostly dependent on the nature of the extraction technique used. In conclusion, S. nodiflora extracts showed good biological potential and data massed from this study could serve as a scientific baseline for further investigation in order to exploit its potential for designing novel bio-products with therapeutic applications.     

Recovery of bioactive compounds from white grape (Vitis vinifera L.) stems as potential antimicrobial agents for human health

The grape is a matrix rich in bioactive compounds and its production generates large quantities of by-products, such as grape stems, which, to date, present low commercial value. However, there is a growing interest in the application of this material as a source of phenolic compounds. Therefore, the present study aims at assessing the phytochemical profile of (poly)phenolic extracts of white Portuguese grape stem varieties produced in the Região Demarcada do Douro (Portugal). The antioxidant activity determined by several assays, as well as the antimicrobial activity using the disc diffusion method against human gastrointestinal pathogenic bacteria of the hydromethanolic extracts, were evaluated. This work presents very positive results as the rich composition in phenolic compounds (94.71–123.09 mg GA⁻¹ and 0.02–73.79 mg g⁻¹ for the total phenol content and for individual phenolics, respectively) presented by grape stems can explain the high antioxidant (0.37–1.17 mmol Trolox g⁻¹) and antimicrobial activities against, essentially, Gram-positive bacteria, and in some cases with higher efficacy than commercial antibiotics. Thus, demonstrating that this wine by-product should deserve greater attention from the pharmaceutical industries due to its excellent biological properties and characteristics not yet applied.     

Phytochemical study,cytotoxic, analgesic,antipyretic and anti-inflammatory activities of Strychnos nux-vomica

The strychnine tree (Strychnos nux-vomica L.) (S. nux-vomica) belonging to family Loganiaceae has been a very promising medication for certain disorders. Different chromatographic methods were used to isolate the phenolic compounds from the aqueous methanolic extract of the S. nux-vomica leaves. Their identification was achieved through spectroscopic techniques. Cytotoxicity, analgesic, antipyretic and anti-inflammatory activities of S. nux-vomica leaves extract were evaluated. Five phenolic compounds were isolated and identified; Kaempferol-7 glucoside 1, 7-Hydroxy coumarin 2, Quercetin-3-rhamnoside 3, Kaempferol 3-rutinoside 4, and Rutin 5. Furthermore, the cytotoxic activity of the extract was evaluated against different cancer cell lines. The extract showed potential cytotoxic activity against human epidermoid larynx carcinoma cells (Hep-2) and against breast carcinoma cell line (MCF-7). Colon carcinoma cells (HCT) were the least one affected by the extract. In addition, the extract exhibited promising analgesic, antipyretic as well as anti-inflammatory activities. It is concluded that, leaves extract of S. nux vomica possess potent cytotoxic, analgesic, antipyretic and anti-inflammatory activities. These activities could be due to the presence of phenolic compounds revealed by our phytochemical investigations.     

Isolation and characterization of antiprotozoal compound-producing Streptomyces species from Mongolian soils

Natural resources are recognized as important sources of potential drugs for treating various infections, and microorganisms are a rich natural source of diverse compounds. Among the world's microorganisms, actinomycetes, which are abundant in soil and marine, are the well-known producers of a wide range of bioactive secondary metabolites and antibiotics. In the present study, four actinomycetes (samples N25, N6, N18, and N12) were isolated from soil samples in Mongolia. Phylogenetic analysis of these isolates revealed that they share the highest similarity with Streptomyces canus (N25), S. cirratus (N6), S. bacillaris (N18) and S. peucetius (N12), based on 16S rRNA gene sequencing. Crude extracts were obtained from them using ethyl acetate, and the crude fractions were separated by thin layer chromatography. The fractions were then evaluated for their cytotoxicities and their anti-Toxoplasma and antimalarial activities in vitro. The S. canus (N25) crude extract was selected for further chemical characterization based on its antiprotozoal activities. Using liquid chromatography-high resolution mass spectrometry, phenazine-1-carboxylic acid (PCA) was detected and identified in the active fractions of the metabolites from strain N25. We next confirmed that commercially available PCA possesses antiprotozoal activity against T. gondii (IC₅₀: 55.5 μg/ml) and Plasmodium falciparum (IC₅₀: 6.4 μg/ml) in vitro. The results of this study reveal that soil actinomycetes are potential sources of antiprotozoal compounds, and that PCA merits further investigation as an anti-protozoal agent.     

In vitro propagation of Caralluma tuberculata and evaluation of antioxidant potential

Present study describes rapid in vitro propagation of Caralluma tuberculata, a traditional medicinal plant, and antioxidant potential of calli and plants extracts. The highest callus induction rate (93.3%) with maximum weight of calli 5.2 g was achieved from shoot tip explants on MS medium supplemented with 9.04 μM 2,4-D and 4.44 μM BA. The maximum shoot induction rate (71.1%) with mean number of shoots 3.66 ± 1.53 and 4.6 cm average shoot length was observed on 13.32 μM BA, 4.52 μM 2,4-D and 2.89 μM GA3 appended in MS medium. The developed shoots were best rooted in the presence of 5.07 μM IAA with 3.0 ± 0.15 roots per plantlet. The plants were successfully acclimatized under in vivo conditions. The plants and calli extracts exhibited good antioxidant activities, however, plant extract activities were more pronounced. The phenolic compounds in plant and calli extracts were 0.16% and 0.057%, respectively. While the flavonoids were 0.092% in plant and 0.039% in calli extract. Total Phenolics, flavonoids; DPPH radical scavenging activity and reducing power potential distributed among different fractions depending upon polarity of the solvent. The highest DPPH scavenging activity and reducing power was exhibited by water fractions; 4.95 mg/mL and 0.729 OD at 10 mg/mL, respectively. The micropropagation protocol can be successfully used for large-scale multiplication and conservation of germplasm of this threatened plant. Furthermore, antioxidant value describes importance of this valuable plant as food and medicine.     

Improved method for identifying and quantifying olive oil phenolic compounds and their metabolites in human plasma by microelution solid-phase extraction plate and liquid chromatography–tandem mass spectrometry

Two methods based on solid-phase extraction (SPE) using traditional cartridges and microelution SPE plates (μSPE) as the sample pre-treatment, and an improved liquid chromatography coupled to tandem mass spectrometry (UPLC–MS/MS) were developed and compared to determine the phenolic compounds in virgin oil olive from plasma samples. The phenolic compounds studied were hydroxytyrosol, tyrosol, homovanillic acid, p-coumaric acid, 3,4-DHPEA-EDA, p-HPEA-EDA, luteolin, apigenin, pinoresinol and acetoxypinoresinol. Good recoveries were obtained in both methods, and the LOQs and LODs were similar, in the range of low μM. The advantage of μSPE, in comparison with SPE cartridges, was the lack of the evaporation step to pre-concentrate the analytes. The μSPE-UPLC–ESI-MS/MS method developed was then applied to determine the phenolic compounds and their metabolites, in glucuronide, sulphate and methylated forms, in human plasma after the ingestion of virgin olive oil.     

Phytochemicals,antioxidant, antimicrobial and phytotoxic activities of Ailanthus altissima (Mill.) Swingle leaves

A comprehensive study on the volatile oil and phenolic constituents of Ailanthus altissima Swingle (Simaroubaceae) leaves was performed. Methanolic extracts of leaves and their hydrodistilled residues were screened for their antioxidant, antimicrobial and phytotoxic properties. The results showed that the leaf volatile oils were a complex mixture of more than a hundred components, mainly composed by non-terpenic compounds (tetradecanol, heneicosane, tricosane and docosane) and sesquiterpene hydrocarbons (α-curcumene and α-gurjunene). Methanolic extracts from leaves contain the highest level of total phenolic content, while those from the hydrodistilled residues showed the highest total flavonoid content. The most frequent phenolic compounds identified by HPLC-DAD–MS were gallic acid, chlorogenic acid, HHDP-galloylglucose, epicatechin, rutin, hyperoside and quercetin-3-galloyl hexoside. Evaluation of the antioxidant activities by using four complementary tests (DPPH, ABTS, 2-deoxyribose and FRAP) showed that both extracts exhibited strong concentration-dependent antioxidant activities. These extracts were efficient against Gram-positive bacteria, but not active against Gram-negative bacterial strains and the yeast Candida albicans. They also exhibited strong inhibitory effects on the germination and the radicle growth of the wild Daucus carota. This work provides scientific supports for the high antioxidant and phytotoxic activities of this species and thus, it may find potential applications in the development of natural herbicides and antioxidants for agro-food and pharmaceutical industries.     

In-vitro free radical scavenging effect and cytotoxic analysis of Black Cummins and Honey formulation

BackgroundThe antioxidant potential and antiproliferative activity of the extracts of Nigella sativa seeds (Black Cummins) and honey formulations are to be explored.MethodThe gas chromatography-mass spectrum (GC–MS) and Thin Layer Chromatography (TLC) fingerprint of Black Cummins and Honey formulation revealed alkaloid, saponin, volatile oil, flavonoid, glycosides, sugar, and phenolic compound in the extract. GC–MS profiling of the cold extract of Nigella sativa seeds and honey formulation shows peaks for eleven fractions of compounds. Using TLC, the phenolic compounds of Nigella sativa seeds and honey formulations were separated.ResultsThe current study discovers the cytotoxic effect of black Cummins seeds and honey formulation on human ovarian cancer (PA-1) cell line as assessed by MTT assay. PA-1 cells were inhibited with the increasing concentration of Nigella sativa seeds extract and honey formulation.ConclusionThe study validates the importance of the tested extracts in the treatment of cancer.     

High-value products from macroalgae: the potential uses of the invasive brown seaweed<Emphasis Type="Italic">, Sargassum muticum</Emphasis>

Marine seaweeds represent an abundant source of natural products and may harbour valuable chemicals. The brown seaweed Sargassum muticum is an invasive species to the coasts of the British Isles, mainland Europe and North America. Attempts at its eradication and control have generally not been successful, although time-consuming and costly. Commercial exploration of this biomass for food, fuel and pharmaceutical products could encourage its harvesting and control. Though S. muticum might be unsuitable as a source of biofuel due to high ash and water content, this rapidly growing macroalga has a naturally high content of antioxidants, carotenoids and phenols, including the well-known anti-cancer compound fucoxanthin, making this species a potential source of a range of pharmaceutically relevant materials.     

Anti-microfouling Activity of Lipidic Metabolites from the Invasive Brown Alga Sargassum muticum (Yendo) Fensholt

The purification of the chloroform extract from the brown invasive macroalga Sargassum muticum, through a series of chromatographic separations, yielded 12 fractions that were tested against strains of bacteria, microalgae, and fungi involved in marine biofilm formation. The chemical composition of four (a, c, g, and k) out of the six fractions that exhibited anti-microfouling activity was investigated. Fraction a contained saturated and unsaturated linear hydrocarbons (C₁₂–C₂₇). Arachidonic acid was identified as the major metabolite in fraction c whereas fraction g contained mainly palmitic, linolenic, and palmitoleic acids. Fraction k was submitted to further purification yielding the fraction kAcaF1e that was composed of galactoglycerolipids, active against the growth of two of the four bacterial strains (Shewanella putrefaciens and Polaribacter irgensii) and all tested fungi. These promising results, in particular the isolation and the activity of galactoglycerolipids, attest the potential of the huge biomass of S. muticum as a source of new environmentally friendly antifouling compounds.     

Variation in antioxidant activity and phenolic content in different organs of two Tunisian cultivars of Olea europaea L.

This paper reports a comparative study based on the antioxidant compounds, total phenol content and antioxidant activities of leaves, stems and fruits from the main Tunisian cultivars, ‘chetoui’ and ‘chemchali’, grown in two different locations, north and south of Tunisia. The repartition of olive phenolic compounds was organ dependant. Therefore, the HPLC analysis indicated that the olive organs from the northern cultivar had the highest level of hydroxybenzoic acids, hydroxycinnamic acids and flavonoid class; which were less in the southern cultivar. Principal component analysis of the phenolic compounds showed discrimination between methanol extracts of the organs olive. Significant differences (p < 0.05) in the levels of phenols, orthodiphenols and flavonoids were found between cultivars and between organs. Antioxidant activities of the methanolic extract from aerial parts of the two studied cultivars were evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assays. In all tests, methanolic extracts of different olive parts showed higher antioxidant activity. These results can be used to discriminate and to characterize the ‘chetoui’ and ‘chemchali’ aerial parts.