Antiviral activity of the extracts of Rhodophyceae from Morocco

Fifty-five aqueous, methanolic, chloroforme-methanolic and dichloromethanolic extracts derived from sixteen species of marine Rhodophyta from the coast of Morocco have been screened for the presence of inhibitory compounds against Herpes simplex virus type 1 (HSV-1) by cell viability method. The aqueous extracts of Asparagopsis armata, Ceramium rubrum, Gelidium pulchellum, Gelidium spinulosum, Halopitys incurvus, Hypnea musciformis, Plocamium cartilagineum, Boergeseniella thuyoides, Pterosiphonia complanata and Sphaerococcus coronopifolius were capable of inhibiting the replication of HSV-1 in vitro at an EC50 (Effective Concentration 50%) ranging from <2.5 to 75.9 μg mL-1. No cytotoxic effect of the aqueous extracts on the Vero cells was observed in the range of the concentrations assayed for all extracts. The results corroborate that marine algae from Morocco can be a rich source of potential antiviral compounds.Keywords: Antiviral, Aqueous extracts, Organic extracts, Rhodophyceae, Herpes simplex viru

The antibacterial potential of the seaweeds (Rhodophyceae) of the Strait of Gibraltar and the Mediterranean Coast of Morocco

The antibacterial activity of extracts from 26 marine Rhodophyceae (8 Ceramiales, 7 Gelidiales, 9 Gigartinales, 1 Bonnemaisoniales and 1 Rhodymeniales) was studied to assess their potential in the pharmaceutical industry. Their bioactivity was analysed from crude methanolic extracts of dried samples against three gram-positive bacteria and two gram-negative bacteria using the disc diffusion technique. The samples were collected from Gibraltar and the Moroccan Mediterranean coast. Of the macroalgae analysed, 96% of extracts were active against at least one of the five test microorganisms. Staphylococcus aureus was the most susceptible microorganism. Methanolic extracts of all seaweed extracts tested in the present study exhibited a broad spectrum of antibacterial activity with inhibition diameters ranging from 10 to 35 mm. An extract of Hypnea musciformis exhibited high antibacterial activity against all the bacteria tested. The results of the present study confirmed the potential use of seaweed extracts as a source of antibacterial compounds.This work was supported by the SAIC (Spanish Agency of International Culture) Morocco-Spain, Project n° A/4931/06 and a grant from the Unesco-Oreal Organization

Antibacterial activity and proximate analysis of Sargassum extracts as cosmetic additives in a moisturizer cream

Indonesia is known for its marine biodiversity, including the richness of its brown seaweed, Sargassum. This genus has attracted many attention as it produces active compounds showing potential for the food, pharmacology and cosmetic industries. In this study, a mixture of S. duplicatum, S. echinocarpum and S. polycystum extracts was applied as an additive in a moisturizer cream serving as an antibacterial agent. Proximate analysis was conducted to evaluate the chemical composition in Sargassum spp. There were 5 moisturizer creams prepared: A (standard), B (without antibacterial agent), C (with antibacterial agent), D (with Sargassum extracts and antibacterial agent) and E (with Sargassum extracts but without antibacterial agent). Antibacterial analyses showed that cream E had the best antibacterial activity in this study. It indicates that the crude extract of Sargassum added in the cream could inhibit the development of bacteria for a longer period of time. Bioactive compounds contained in S. duplicatum, S. echinocarpum, S. polycystum are steroids, quinones, flavonoids and alkaloids. Saponins were only found in S. duplicatum. The five cosmetic creams presented adequate odor and color. These results indicate that Sargassum shows a promising potential as a cosmetic additive that could replace commercial antibacterial agents

Potentiality of Using Spreading Sargassum Species From Indonesia as an Interesting Source of Antibacterial and Radical Scavenging Compounds: a Preliminary Study

As an archipelagic country with 95,181 km long coastline, Indonesia has great potential as the producer of seaweeds. The diverse phyla of marine macroalgae (red, brown and green seaweeds) are known to produce molecules which are attractive for diverse industries. Applications of algal products range from simple biomass production for food, feed and fuels to valuable products such as sugar polymers, cosmetics, pharmaceuticals, pigments, and food supplements. Seaweeds also have the potential to be used as a source of new bioactive for human, animal or plant health, as well as a source of new synthons and biocatalysts in sustainable chemistry (Bourgougnon and Stiger-Pouvreau, 2011). In this paper, among species of economic value we focus on brown seaweeds belonging to family Sargassaceae and genus Sargassum spreading along Indonesian coasts. Members of this genus are especially abundant in tropical and subtropical regions (Zemke-White and Ohno, 1999). The purpose of this study is to analyze the antibacterial and antioxidant activity of three species of Sargassum, i.e. S. echinocarpum, S. duplicatum and S. polycystum. Both polar and non-polar extracts have been prepared from those three species. In vitro antibacterial activities of extracts were evaluated against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. Results indicated all the three species tested showed an antibacterial activity. The most effective antibacterial activity against S. aerous was from S. echinocarpum with ethil asetat, inhibition zone 1.13 ± 0.25 mm; S. duplicatum with N-Hexane was most effective against E. coli, 1.20 ± 0.28 mm

Bacterial isolates from bryozoanPleurocodonellina sp.: Diversity and antimicrobial potential against pathogenic bacteria

There isan urgent need to discover new compounds with antibacterial activity, which can be developed into lead structures for the treatment of human disease caused by multidrug-resistant (MDR) bacteria. In this study, we focussed on bryozoan-associated bacteria to screen them toward antibacterial activities, since the microbiome of these organisms can still be regarded as under-investigated. Most of the few publications about bryozoan-associated bacteria focused on taxonomy and the potential as producers of antibacterial natural products were neglected. Four specimens of bryozoan Pleurocodonellina sp. were collected from Teluk Awur, Jepara inJava Sea, Indonesia. Therefrom, 56 bacterial strains were isolated, and 17 displayed antibacterial activitiesagainst MDR bacteria Pseudomonas aruginosa,Klebsiella pneumoniae, Acinetobacter baumannii, Enterobacter cloacae, and methicillin-resistant Staphylococcus aureus (MRSA). Taxonomic identification of the bacteria by 16S rRNA gene sequencing revealed them belonging to the genera Virgibacillus, Pseudoalteromonas, Halomonas, and Bacillus. Most interestingly, the genus Virgibacillus was dominantly obtained from the Pleurocodonellina sp. specimens, i.e., 12 active isolates. Nevertheless, the best activities against MDR bacteria(both Gram-positive and Gram-negative) were contributed to isolates showing >99% identity to Pseudoalteromonas. The results further suggest adding the genus Virgibacillus as bacteria associated with bryozoan, since to the best of our knowledge there were no reports of this genus isolated from bryozoan

Antiviral Activities of Sulfated Polysaccharides Isolated from Sphaerococcus coronopifolius (Rhodophytha, Gigartinales) and Boergeseniella thuyoides (Rhodophyta, Ceramiales)

Water-soluble sulfated polysaccharides isolated from two red algae Sphaerococcus coronopifolius (Gigartinales, Sphaerococcaceae) and Boergeseniella thuyoides (Ceramiales, Rhodomelaceae) collected on the coast of Morocco inhibited in vitro replication of the Human Immunodeficiency Virus (HIV) at 12.5 μg/mL. In addition, polysaccharides were capable of inhibiting the in vitro replication of Herpes simplex virus type 1 (HSV-1) on Vero cells values of EC50 of 4.1 and 17.2 μg/mL, respectively. The adsorption step of HSV-1 to the host cell seems to be the specific target for polysaccharide action. While for HIV-1, these results suggest a direct inhibitory effect on HIV-1 replication by controlling the appearance of the new generations of virus and potential virucidal effect. The polysaccharides from S. coronopifolius (PSC) and B. thuyoides (PBT) were composed of galactose, 3,6-anhydrogalactose, uronics acids, sulfate in ratios of 33.1, 11.0, 7.7 and 24.0% (w/w) and 25.4, 16.0, 3.2, 7.6% (w/w), respectively

Bacteriocin as Weapons in the Marine Animal-Associated Bacteria Warfare: Inventory and Potential Applications as an Aquaculture Probiotic

As the association of marine animals with bacteria has become more commonly recognized, researchers have increasingly questioned whether these animals actually produce many of the bioactive compounds originally isolated from them. Bacteriocins, ribosomally synthesized antibiotic peptides, constitute one of the most potent weapons to fight against pathogen infections. Indeed, bacteriocinogenic bacteria may prevent pathogen dissemination by occupying the same ecological niche. Bacteriocinogenic strains associated with marine animals are a relevant source for isolation of probiotics. This review draws up an inventory of the marine bacteriocinogenic strains isolated from animal-associated microbial communities, known to date. Bacteriocin-like inhibitory substances (BLIS) and fully-characterized bacteriocins are described. Finally, their applications as probiotics in aquaculture are discussed

Activités biologiques de principes actifs de différents extraits d algues rouges marines (Rhodophyceae) de la côte atlantico-méditerranéenne du Maroc

Les potentialités biologiques des algues benthiques des côtes marocaines sont méconnues. Dans le but de la valorisation de cette ressource, une évaluation de l activité antibactérienne, cytotoxique, antivirale, antioxydante et anti-algale a été réalisée à partir de 130 extraits de polarité différente issus de 29 espèces de Rhodophycées (1 Bonnemaisoniales, 8 Céramiales, 3 Corallinales, 7 Gélidiales, 9 Gigartinales, 1 Rhodymeniales). Les extraits ont été testés contre 11 bactéries Gram-négatif et 10 bactéries Gram-positif par la méthode de diffusion par disque. Soixante-quinze pourcent des extraits sont actifs sur au moins une souche bactérienne. L évaluation de l activité antioxydante a été réalisée à travers 3 tests différents. Lors du test au DPPH, 4 extraits méthanoliques ont permis la transformation du radical de DPPH en forme réduite avec une CE50 située entre 96 et 862 g.mL-1. Dans le cadre du test au b-carotène, 7 extraits méthanoliques ont montré une activité contre les radicaux peroxydes avec une CE50 entre 9 et 176 g.mL-1. Dans le test au désoxyribose, le pourcentage d inhibition des radicaux du groupe hydroxyle varie entre 25 et 68% pour 5 extraits aqueux dont le plus important est l extrait d Asparagopsis armata. L évaluation de l activité antialgale vis-à-vis des Diatomophycées, Cylindrotheca fusiformis, C. closterium et Amphora coffeaeformis, par l analyse de la chlorophylle-a a montré que la concentration effective 50% varie entre des valeurs inférieures à 10 g.mL-1 et d autres supérieures à 1000 g.mL-1. L évaluation de l activité antivirale sur le modèle virus d Herpes simplex de type-1/Cellules Véro par viabilité cellulaire met en évidence que les extraits aqueux sont capables d'empêcher in vitro la réplication de VHS-1 à une CE50 (concentration effective 50%) qui varie de <2,5 à < 75,9 g.mL-1. Aucun effet cytotoxique n a été observé avec les extraits aqueux sur les cellules Véro dans la gamme des concentrations étudiées 2,5 et 250,0 g.mL-1. Deux polysaccharides sulfatés isolés de Sphaerococcus coronopifolius (Gigartinales) et Boergeseniella thuyoides (Céramiales) respectivement présentent in vitro une inhibition de la réplication de Virus de l'Immunodéficience Humaine (VIH) par mesure de l enzyme transcriptase inverse dans les cellules CEM et la formation de syncitia dans les cellules MT4 après 3 jours à 12,5 g.mL-1. Ils sont aussi capables d inhiber également in vitro la réplication du VHS-1 dans les cellules Véro avec une concentration effective (CE50), respectivement, de 4,1 à 17,2 g.mL-1. Aucune toxicité supérieure à 200,0 g.mL-1 n a été observée sur les cellules Véro et MT4. L activité des polysaccharides contre le VIH-1 et le VHS-1 se manifeste juste après l infection. La purification par Chromatographie de Partage Centrifuge (CPC) de l extrait chloroforme-méthanol d Asparagopsis armata a permis d obtenir des fractions contenant deux à quatre composés. Les techniques de résonance magnétique nucléaire (RMN) et la spectrométrie de masse (SM) ont mis en évidence la présence des acides gras, des acides aminés et des composés aromatiques. Des signaux de phénols et des composés polysaccharidiques ont également été caractérisés. La présence continue des acides gras dans toutes les fractions actives analysées, nous permet de déduire qu ils pourraient contribuer dans l activité antibactérienne.The biological potentialities of seaweeds benthic of the Moroccan coast are not recognized. With the aim of the valuation of this resource, an evaluation of the antibacterial activity, cytotoxic, antiviral, antioxidant and anti-algal was realized from 130 extracts of different polarity stemming from 29 species of Rhodophyceae (1 Bonnemaisoniales, 8 Ceramiales, 3 Corallinales, 7 Gelidiales, 9 Gigartinales, 1 Rhodymeniales). Extracts were tested against 11 bacteria Gram-negatives and 10 bacteria Gram-positives by the method of diffusion by disk. Seventy-five percent of the extracts are active on at least a bacterial strain. The evaluation of the antioxidant activity was realized through 3 different tests. During the test in the DPPH, 4 methanolic extracts allowed the transformation of the radical of DPPH in shape reduced with EC50 situated between 96 and 862 g.mL-1. Within the work of the test in b-carotene, 7 methanolic extracts showed an activity against the peroxide radicals with EC50 between 9 and 176 g.mL-1. In the test in the deoxyribose, the percentage of inhibition of the radicals of the group hydroxyls varies between 25 and 68 % for 5 aqueous extracts, of which most important is the extract of Asparagopsis armata. The evaluation of the anti-algal activity towards Diatomophyceae, Cylindrotheca fusiformis, C. closterium and Amphora coffeaeformis, by the analysis of chlorophyll-a showed that the effective concentration 50 % varies between values lower than 10 g.mL-1 and the other superiors in 1000 g.mL-1. The evaluation of the antiviral activity on the model virus of Herpes simplex of type-1 / Vero cells by cellular viability revealed that the aqueous extracts are capable of preventing in vitro the replication of VHS-1 in a EC50 (effective concentration 50 %) which varies of < 2.5 at < 75.9 g.mL-1. No cytotoxic effect was observed with the aqueous extracts on Vero cells in the range of the studied concentrations 2.5 and 250 g.mL-1.Two sulfated polysaccharides isolated of Sphaerococcus coronopifolius (Gigartinales) and Boergeseniella thuyoides (Ceramiales) present in vitro an inhibition of the replication of Human Immunodeficiency Virus (HIV) respectively by measure of the reverse transcriptase enzyme in cells CEM and formation of syncitium in cells MT4 after 3 days in 12.5 g.mL-1. They are also capable of inhibiting also in vitro the replication of the HSV-1 in cells Vero with an effective concentration (EC50), respectively of 4.1 and 17.2 g.mL-1. No toxicity superior to 200.0 g.mL-1 was observed on Vero cells and MT4. The activity of polysaccharides against the HIV-1 and the HSV-1 appears just after the infection.The purification by Centrifugal Partition Chromatography (CPC) of the chloroform-methanol extract of Asparagopsis armata allowed obtaining containing fractions two in four compounds. The techniques of nuclear magnetic resonance (NMR) and the mass spectrometry (MS) revealed the presence of fatty acids, amino acids, aromatic compounds. Signals of phenols and polysaccharidic compounds also characterized. The continuous presence of the fatty acids in all the analyzed active fractions allows us to deduct that they could contribute in the antibacterial activity.LORIENT-BU (561212106) / SudocSudocFranceF

Recherche d'activités antimicrobiennes chez des mollusques marins (purification et caractérisation partielle de peptides antimicrobiens isolés à partir de l'hémolymphe de Crassostrea gigas et de bactéries associées)

Les systèmes de communication chimique constituent un élément indispensable dans l établissement des relations intra- ou inter-espèces en milieu marin, tissant un réseau de relations entre individus, au sein d un écosystème. Les invertébrés dépourvus de système immunitaire à mémoire et au mode de vie sessile produisent des métabolites bioactifs jouant un rôle essentiel dans la réponse aux pressions environnementales telles que la prédation et la défense vis-à-vis d autres organismes potentiellement pathogènes. L objectif de ces travaux a été d identifier la présence de peptides antimicrobiens chez des mollusques bivalves et des gastéropodes d importance commerciale. Ainsi, la recherche de molécules de défense antimicrobiennes de nature peptidique a été conduite dans des extraits acides des mollusques bivalves, Cerastoderma edule, Ruditapes philippinarum, Ostrea edulis et gastéropodes, Buccinum undatum, Littorina littorea et Crepidula fornicata, ainsi qu à partir de l hémolymphe de Crassostrea gigas. Les extraits ont été pré-purifiés par extraction sur phase solide C18 (SPE) et l élution a été réalisée par 3 paliers successifs de 10%, 40% et 80% d ACN-0,1% TFA. L activité antibactérienne a été évaluée via la détermination de la CMI sur un ensemble de bactéries à Gram+ et à Gram- ; et l activité antivirale a été déterminée in vitro sur le modèle virus Herpes simplex type 1/cellules Vero via la viabilité cellulaire. Les espèces C. edule, L. littorea et C. gigas se sont révélées être les espèces les plus efficaces et non cytotoxiques. Une caractérisation partielle de l activité détectée chez ces espèces a permis de déterminer la nature peptidique des molécules actives. La purification des peptides antimicrobiens a été conduite sur l hémolymphe de C. gigas et a permis l identification d un peptide dont la structure de type lantibiotique laisse présager une origine bactérienne. L hypothèse d une association entre C. gigas et des bactéries nous a conduit, à partir de cultures d huîtres non axéniques, à rechercher des bactéries antagonistes dans l hémolymphe et a permis d isoler 2 Vibrio spp. et 3 Pseudoalteromonas spp. A partir de la bactérie Pseudoalteromonas spp. souche hCg 5, un composé actif a été partiellement caractérisé. L ensemble de ces résultats suggère que les bactéries associées au système immunitaire pourraient jouer un rôle essentiel dans la défense des bivalves.The chemical communication systems constitute an essential element in the establishment of intra- or inter-species relationships in marine environment, weaving a dense network of relations between individuals, in ecosystem. The invertebrates lacking of an immune system and usually sessile produce this type of bioactive metabolites playing a crucial role in the answer to the environmental pressures like the predation and the defence against potentially pathogens organisms. The aim of this work was to identify antimicrobial peptides in commercially bivalve and gastropod marine molluscs. Thus, the search for antimicrobial molecules from peptidic nature was undertaken in acid extracts of bivalve molluscs Cerastoderma edule, Ruditapes philippinarum, Ostrea edulis, and gastropods Crepidula fornicata, Buccinum undatum and Littorina littorea and from Crassostrea gigas hemolymph. The extracts were pre-purified by Solid Phase Extraction C18 (SPE) and elution was ensured by three successive steps of 10%, 40% and 80% of ACN-0.1% TFA. The antibacterial activities were assayed by determination of the CMI against a panel of target bacteria including Gram+ and Gram- bacteria. In parallel, antiviral activities were assayed in vitro against Herpes simplex virus type 1 and Vero cells by cell viability. The species C. edule, L. littorea and C. gigas proved to be the most effective and non cytotoxic species. A partial characterization of the activity detected in these species allowed determining the protenaceous nature of the active molecules. The purification of antimicrobial peptides realised on the C. gigas hemolymph led us to the identification of a peptide which structure lets foresee a bacterial origin. The hypothese of an association between C. gigas and bacteria led us from non axenic oysters culture to search for antagonist bacteria in C. gigas hemolymph and has conduced to isolate 2 Vibrio spp. and 3 Pseudoalteromonas spp. The Pseudoalteromonas spp. hCg 5 strain, allowed to partially characterized an active compound. Whole of these results suggests that the bacteria associated with the immune system could play an essential function of defence in bivalves.LORIENT-BU (561212106) / SudocSudocFranceF