Letteratura scientifica selezionata sul tema "Caulerpa cylindracae"

Biological invasion is the successful spread and establishment of a species in a novel environment that adversely affects the biodiversity, ecology, and economy. Both invasive and non-invasive species of the Caulerpa genus secrete more than thirty different secondary metabolites. Caulerpin is one of the most common secondary metabolites in genus Caulerpa. In this study, caulerpin found in invasive Caulerpa cylindracea and non-invasive Caulerpa lentillifera extracts were analyzed, quantified, and compared using high-performance thin layer chromatography (HPTLC) for the first time. The anticancer activities of caulerpin against HCT-116 and HT-29 colorectal cancer (CRC) cell lines were also tested. Caulerpin levels were found higher in the invasive form (108.83 ± 5.07 µg mL−1 and 96.49 ± 4.54 µg mL−1). Furthermore, caulerpin isolated from invasive Caulerpa decreased cell viability in a concentration-dependent manner (IC50 values were found between 119 and 179 µM), inhibited invasion-migration, and induced apoptosis in CRC cells. In comparison, no cytotoxic effects on the normal cell lines (HDF and NIH-3T3) were observed. In conclusion, HPTLC is a quick and novel method to investigate the caulerpin levels found in Caulerpa extracts, and this paper proposes an alternative utilization method for invasive C. cylindracea due to significant caulerpin content compared to non-invasive C. lentillifera.

The invasive macroalga Caulerpa cylindracea has spread widely in the Mediterranean Sea, becoming a favorite food item for native fish for reasons yet unknown. By using a combination of behavioral, morphological, and molecular approaches, herein we provide evidence that the bisindole alkaloid caulerpin, a major secondary metabolite of C. cylindracea, significantly increases food intake in the model fish Danio rerio, influencing the regulation of genes involved in the orexigenic pathway. In addition, we found that the compound improves fish reproductive performance by affecting the hypothalamus–pituitary–gonadal axis. The obtained results pave the way for the possible valorization of C. cylindracea as a sustainable source of a functional feed additive of interest to face critical challenges both in aquaculture and in human nutrition.

The biological invasion of the green algae Caulerpa cylindracea represents a serious scientific and public issue in the Mediterranean Sea, essentially due to strong modifications both to habitat structure and native benthic communities. Although alterations in health status and changes in flesh quality of some marine species (dietary exposed to C. cylindracea) have been observed, no studies on cause-effect relationships have been carried out. Here, for the first time, through a controlled feeding experiment followed by 1H NMR Spectroscopy and multivariate analysis (PCA, OPLS-DA), we showed that caulerpin taken with diet is directly responsible of changes observed in metabolic profile of fish flesh, including alteration of lipid metabolism, in particular with a reduction of ω3 PUFA content. The potential of caulerpin to directly modulate lipid metabolism opens up new questions about causal mechanism triggered by algal metabolite also in view of a possible exploitation in the nutraceutical/medical field.

ABSTRACT Background: A lot of food can repair gastric mucosal damage. For example, sea grapes or the Caulerpa cylindracea with its flavonoid content. Anti-inflammatory and anti-ulcer effect can reduce gastric lesions due to ulcerogenic agents. Indomethacin is used to induce gastric ulcers in experimental animals. Based on this background, this study was conducted to analyze the effect of Caulerpa cylindracea extract, on the histopathological picture of gastric mucosal damage of Rattus norvegicus male rats. Method: 32 male Rattus norvegicus rats were divided into 4 groups, (1) Group K(-), the untreated group, (2) Group K(+) induced by indomethacin 30mg/kgBB per head (3) Group P1 induced by indomethacin 30 mg/kgBB and Caulerpa cylindracea extract 1gr/100grBB per head, (4) Group P2, induced by indometacin 30mg/kgBB and 2gr/100grBB of Caulerpa cylindracea extract per head. Result: There was a significant difference (p = 0.001) between the degree of gastric mucosal damage in group K(+) given only indomethacin and group P1 given Indomethacin and 1gr/100grBB Caulerpa cylindracea extract. There was a significant difference (p = 0.001) between group K(+) and group P2 that given Indomethacin and 2g/100grBB Caulerpa cylindracea extract. There was a significant difference (p = 0.004) between group P1 and group P2. Data revealed on group K(-) without any treatment did not obtain significant results (p = 0.060) with group P2. Conclusion: Giving Caulerpa cylindracea extract with 1 gr/100grBB dose and 2gr/100grBB dose can repair mucosal damage in Rattus norvegicus male rats induced by indomethacin.

Although the chemical warfare between invasive and native species has become a central problem in invasion biology, the molecular mechanisms by which bioactive metabolites from invasive pests influence local communities remain poorly characterized. This study demonstrates that the alkaloid caulerpin (CAU)—a bioactive component of the green alga Caulerpa cylindracea that has invaded the entire Mediterranean basin—is an agonist of peroxisome proliferator-activated receptors (PPARs). Our interdisciplinary study started with the in silico prediction of the ligand-protein interaction, which was then validated by in vivo, ex vivo and in vitro assays. On the basis of these results, we candidate CAU as a causal factor of the metabolic and behavioural disorders observed in Diplodus sargus, a native edible fish of high ecological and commercial relevance, feeding on C. cylindracea. Moreover, given the considerable interest in PPAR activators for the treatment of relevant human diseases, our findings are also discussed in terms of a possible nutraceutical/pharmacological valorisation of the invasive algal biomasses, supporting an innovative strategy for conserving biodiversity as an alternative to unrealistic campaigns for the eradication of invasive pests.

The role of habitat degradation on the spread of the alien green alga Caulerpa cylindracea is reported here by comparing observations achieved through a multi-year assessment on three Mediterraneans habitats, namely Posidonia oceanica meadows, Phyllophora crispa turf, and coralligenous reefs. Due to the peculiarity of the study site, both natural-reference and impacted conditions were investigated. C. cylindracea occurred in all the studied habitats under impacted conditions. High susceptibility to the invasion characterized impacted P. oceanica, where Caulerpa cover reached 70.0% in summer months. C. cylindracea cover did not differ significantly among conditions in P. crispa turf, where values never exceeded 5.0%. Conversely, the invasive green algae was low in abundance and patchily distributed in coralligenous reefs. Our results confirmed that habitat loss enhances the spread of C. cylindracea, although with different magnitudes among habitats. Dead matte areas of P. oceanica represented the most vulnerable habitat among those analyzed, whereas coralligenous reefs were less susceptible to the invasion under both the studied conditions.

The invasive species Caulerpa racemosa var. cylindracea represents a serious threat to the diversity of benthic assemblages in the Mediterranean Sea. In the present study, a removal experiment was carried out to test whether, after 18 months of C. racemosa var. cylindracea exclusion, the macrophyte assemblage resembled a non-invaded assemblage. The results show that in the assemblage invaded by C. racemosa var. cylindracea the number of species, macrophyte cover, Shannon diversity and Pielou's evenness were lower than in the non-invaded assemblage. Erect perennial species were particularly affected and other introduced species were significantly reduced or completely excluded. After 18 months of removal/exclusion of C. racemosa var. cylindracea, only partial recovery of the macrophyte assemblage could be observed. Species numbers, total cover and erect perennial species cover were still significantly lower than in the non-invaded plots. However Shannon diversity and Pielou's evenness had reached comparable levels. In contrast to native macrophytes, the total cover of other introduced species reached a level comparable to the non-invaded plots. In summary, the present study revealed that after 18 months of C. racemosa var. cylindracea exclusion: (i) only partial recovery of the macrophyte assemblage occurred; and (ii) the development of other invasive species was favoured by the absence of C. racemosa var. cylindracea (Sisyphus effect).

AbstractWe report on the relationships between some conspicuous Mediterranean photophilous sponge species and Caulerpa cylindracea, a non-indigenous species. A diversification of defence strategies and behaviour is highlighted in target species belonging to different orders of Demospongiae from a western Mediterranean Marine Protected Area (NW Sardinian Sea). Caulerpa cylindracea displays a strongly invasive behaviour during body colonization of the Irciniidae Sarcotragus spinosulus and Ircinia retidermata (order Dictyoceratida). These sponges possess pre-adaptive defensive morpho-functional and physiological traits enabling them to partly withstand algal invasion. Also Aplysina aerophoba (order Verongiida) seems to be able to control colonization. Successful anti-Caulerpa strategies characterize the rarely affected Crambe crambe (order Poecilosclerida). Species-specific competitive strategies are displayed at different levels of body architecture, behaviour and physiology by native sponge species. The invasion patterns on sponges, the invasion dynamics in 2016–2017 and topographic distribution of C. cylindracea on S. spinosulus confirm this algal species as a threat, with potential long-term effects on sponge assemblages. Data suggest other kinds of poorly investigated synergic stressors affecting these habitat-forming species. Defence strategies of sponge species take the form of: (1) passive deterrence by morpho-functional pre-adaptive traits as growth form, biomass amount, surface traits, and microhabitat within the sponges' aquiferous system; (2) active physiological defence, whereby the morphology/anatomy of the sponge body is adapted to control invaders, by body remodelling and regenerative processes within the aquiferous system and at the sponge surface; (3) presumed active chemical defence by exudation processes of bioactive compounds.

Caulerpa cylindracea is an invasive seaweed in the Mediterranean Sea. In this study, we propose an alternative method to utilise the biomass of C. cylindracea to synthesize silver nanoparticles (AgNPs). UV-VIS spectroscopy, FT-IR and X-ray diffraction were used in characterization steps. The results show that optimum conditions such as time, initial concentration of AgNO3 and temperature were found to be 240 min, 0.1 M AgNO3 and 85˚C, respectively. The measured particle size of the synthesized AgNPs were 22 nm. Since AgNPs were encapped by the secondary metabolites of C. cylindracea, the synthesized AgNPs showed stable solubility in aqueous conditions. The experimental data related to synthesis of AgNPs were modelled by using artificial neural network (ANN). Agitation time and rate, temperature, pH, concentration of AgNO3 and extract were chosen as input and absorbance values were chosen as output. ANN modelling study exhibited that Bayesian regularization backpropagation, scaled conjugate gradient backpropagation and Levenberg-Marquardt backpropagation algorithms better modelled the experimental data compared to studied 11 backpropagation algorithms. In conclusion, biomass of invasive seaweeds can be used to synthesize AgNPs for commercial use and this will bring a new perspective to utilisation of the biomass of invasive seaweeds. A possible economical value may create a stress on the spread of these alien species in the Mediterranean Sea.

In the Mediterranean Sea, the spread of the invasive algae Caulerpa cylindracea appears to be one of the most severe threat to the biodiversity of the coralligenous benthic communities. The magnitude of its effects may be modulated by the features of recipient communities, considering the high variability in species composition and relative abundance that characterize these biogenic reefs. The structure of benthic assemblages, taxa abundances and species diversity were investigated using a manipulative approach at three study sites in Elba Island and applying a multifactorial experimental design. Benthic assemblages’ structure, abundance and diversity were investigated in relation to the possible effects of both presence and absence of C. cylindracea and of the gorgonian Paramuricea clavata. Being C. cylindracea widely spread in the study sites, its absence in the specifically intended plots was maintained by periodical manual removals, while appropriate plots with and without P. clavata were selected for proper experimental setup. The coverage of P. clavata was comparatively low and, except a slightly but significant increase of benthic species richness in presence of the gorgonian, no other effects of its presence on the benthic assemblages among sites nor in relation to the presence of C. cylindracea were detected. Overall, Corallinaceae encrusting algae, turfs and sediment dominated in term of percent cover both in presence and absence of C. cylindracea. The effects of the presence of C. cylindracea on the structure of benthic assemblages appeared moderate and site specific. That is probably due to high heterogeneity of environmental conditions and different invasiveness of C. cylindracea at the investigated spatial scales.

Dans le Golfe de Marseille, l’espèce introduite invasive Caulerpa racemosa var. Cylindracea, originaire de l’Australie du sud-ouest, a été découverte en 1998. Actuellement, elle colonise de larges surfaces sur tous les substrats, de la surface à 40 m de profondeur, à l’exception des herbiers denses de Posidonia oceanica. Dans la rade sud, elle domine largement les communautés macrophytiques sur matte morte de P. Oceanica et sur le Détritique Côtier. Sur la matte morte, C. Racemosa a présenté une régression totale en hiver 2002/2003. Depuis, ses populations persistent toute l’année avec un maximum de développement en automne et une régression plus ou moins marquée en hiver. Dans le Détritique Côtier, elle se maintient toute l’année avec un pic de développement en début d’été et des biomasses inférieures à celles mesurées sur matte morte. La présence de prairies denses de C. Racemosa entraîne des changements importants et similaires dans les communautés macrophytiques des deux communautés : le nombre d’espèces, la couverture, la diversité et l’équitabilité sont diminués et la structure des communautés est altérée. C. Racemosa entre en compétition avec les espèces dressées et filamenteuses, notamment avec les autres espèces invasives présentes dans la région (principalement Asparagopsis armata / ‘Falkenbergia rufolanosa’ et Womersleyella setacea) dont elle réduit fortement l’abondance. Dans les deux communautés, les variations saisonnières de la diversité et de l’équitabilité sont inversement corrélées au développement de C. Racemosa, avec des valeurs minimales lors de son maximum de développement et des valeurs maximales lors de sa régression hivernale. Sur matte morte, le nombre d’espèces et la biomasse les plus élevés ont été observés sur des prairies âgées de C. Racemosa. Cette végétation épiphyte disparaît avec la chute des frondes de C. Racemosa. En contraste avec les zones de référence, des fluctuations pluriannuelles importantes des paramètres descriptifs ont été notées dans les communautés de matte morte envahies témoignant de la nécessité d’élargir l’échelle temporelle des études d’impacts des espèces invasives. La disparition naturelle de C. Racemosa en hiver 2002/2003 n’a pas permis aux communautés macrophytiques de se rétablir complètement, seule une légère amélioration s’est manifestée au niveau de certains paramètres descriptifs, confirmant l’incidence négative de C. Racemosa sur la végétation. Malgré une éradication expérimentale de 18 mois, pendant laquelle C. Racemosa a été enlevée manuellement tous les mois, le rétablissement complet des communautés macrophytiques n’a pas non plus été observé. Au contraire, cette éradication a favorisé en priorité le développement d’autres espèces invasives, surtout la Rhodophyta filamenteuse Womersleyella setacea. Seule la diversité et l’équitabilité ont atteint des niveaux comparables à la référence. Au terme de l’expérience, C. Racemosa était toujours présente sous forme de régénérations (sans doute à partir de fragments ayant échappé à l’éradication) illustrant les difficultés du contrôle mécanique de l’espèce en Méditerranée. 16 ans après sa découverte en Méditerranée, Caulerpa racemosa var. Cylindracea est déjà présente dans 12 pays. Compte tenu de l’étendue des surfaces concernées et de son comportement hautement invasif, elle est responsable d’un changement global d’écosystèmes ce qui la range parmi les pires macrophytes introduits à ce jour en Méditerranée. Sa prise en considération à une échelle internationale apparaît comme une priorité dans le cadre de la gestion des écosystèmes côtiers
In the Gulf of Marseille, the introduced invasive Caulerpa racemosa var. Cylindracea from south-western Australia has been sighted for the first time in 1998. Presently, it colonizes large surfaces on all kinds of substrates from the surface down to 40 m of depth with the exception of dense Posidonia oceanica seagrass meadows. In the southern bay, C. Racemosa largely dominates the macrophyte assemblages of dead P. Oceanica ‘matte’ and deep detritic bottoms. On dead ‘matte’, C. Racemosa completely regressed in winter 2002/2003. Ever since, its populations have been persisting all year round with a maximum development in autumn and a more or less pronounced regression in winter. On deep detritic bottoms, C. Racemosa maintains permanent populations throughout the year with a peak development in early summer and biomasses generally lower than those recorded on dead ‘matte’. The presence of dense C. Racemosa meadows triggers important changes that are similar between the two macrophyte assemblages: number of species, macrophyte cover, diversity and evenness are reduced and the structure of the assemblages is altered. C. Racemosa competes with erect and filamentous species, especially with the other invasive species present in the area (mainly Asparagopsis armata / ‘Falkenbergia rufolanosa’ and Womersleyella setacea), whose abundances are largely reduced. In both communities, the seasonal variations of diversity and evenness are found to be inversely correlated with the development of C. Racemosa, showing minimal values during its maximum development and maximal values during the winter regression. On dead ‘matte’, the highest number of species and highest macrophyte cover was recorded on old meadows of C. Racemosa. This epiphytic vegetation disappears during the disintegration of the C. Racemosa fronds. In contrast with the reference zone, important large-scale temporal variations occur in the descriptive parameters of the invaded assemblages on dead ‘matte’. This testifies for the necessity to enlarge the temporal scale in studies of invasive species impacts. The natural disappearance of C. Racemosa in winter 2002/2003 did not result in a complete recovery of the assemblage, only some descriptive parameters showed slight increases confirming the negative impact of C. Racemosa on the vegetation. Despite an 18 month experimental eradication, during which C. Racemosa was removed manually each month, no complete recovery of the assemblage could be observed. On the contrary, the eradication primarily favoured the development of other invasive species, mainly of the filamentous Rhodophyta Womersleyella setacea. Only diversity and evenness reached levels comparable to the reference. The presence of C. Racemosa regenerations inside the eradicated zones (certainly arising from small fragments missed by the eradication) at the end of the experiment is an evidence for the difficulty of mechanically controlling this species in the Mediterranean Sea. 16 years after its first discovery in the Mediterranean Sea, Caulerpa racemosa var. Cylindracea is already present in 12 countries. Considering the large surface areas colonized and its highly invasive character, C. Racemosa can at present be considered as one of the worst macrophytes introduced into the Mediterranean Sea. In the frame of coastal ecosystems management, it is a priority to consider C. Racemosa on an international scale

Populations of the green marine macroalgae Caulerpa taxifolia and Caulerpa cylindracea have invaded and spread throughout Mediterranean after they were introduced from Australia. In Australia, these tropical to subtropical species have established invasive populations in New South Wales, South Australia, and most recently, for C. cylindracea, in Victoria. Significant efforts have been made to elucidate the invasion history and geographic source locations of Mediterranean populations. The same effort has been lacking in Australia. Both species have provided challenges for molecular ecologists because of their predominantly clonal reproduction and low genetic variation within invasive populations in the case of C. taxifolia, and very high intra-individual genetic variation in C. cylindracea. In chapter 2, I present a detailed review of the literature about the molecular ecology of C. taxifolia and C. cylindracea. I outline the phylogenetic and phylogeographic research on both of these species. The methodology and analysis of each study is critiqued. From this analysis I identify the knowledge gaps about invasive Caulerpa spp., and how to approach further research given advances in technology and knowledge of the organisms. In chapter 3, I present a modified Ion Torrent next generation sequencing protocol that was used to identify novel single nucleotide polymorphisms (SNPs) in C. taxifolia. This approach resulted in the successful identification of a suite of SNPs. Primer development and SNP validation was performed for the Sequenom MassArray, and 184 specimens from 10 Australian populations from Queensland, New South Wales, South Australia, and Western Australia, were genotyped. The data build on existing phylogeographic data for C. taxifolia in Australia, and support a model of anthropogenic distribution rather than natural dispersal. Anthropogenically mediated primary introductions may have been caused by aquarium releases, while secondary spread has been facilitated by heavy boat traffic in affected areas. Finally I discuss the evidence of the so called “invasive strain” of C. taxifolia, and conclude that there is no such thing, and that the assumption that an “invasive strain” exists has undermined the scientific objectivity of 30 years of study of invasive Caulerpa species. Chapter 4 represents the first phylogeographic study of invasive and native C. cylindracea populations in Australia. In this chapter I used variation in the rpl16-rps3 region of the chloroplast to test hypotheses about the origins and dispersal mechanisms responsible for the establishment of invasive populations of C. cylindracea in South Australia. Molecular data does not support natural dispersal of C. cylindracea, a finding that is supported by a lack of species records of C. cylindracea for 2600 km between southern Western Australia and the South Australia. In chapter 5, I determined if RNA:DNA, Protein:DNA, and Protein:RNA ratios can be used to quantify the effect of ocean warming and acidification on C. taxifolia and C. trifaria. Protein profiles were also examined for effects of ocean warming and acidification. While no significant effects were observed on the ratios, concentrations of DNA were positively affected by temperature, while negative impacts on protein were associated with decreasing pH. The protein profiles also allowed me to determine if the invasive tropical and subtropical C. taxifolia is likely to be impacted differently by ocean warming and acidification than the native temperate C. trifaria. Protein profile data revealed that C. trifaria specimens experience greater levels of metabolic stress than C. taxifolia at lower pH, and that the invasive C. taxifolia will continue to thrive in warmer and more acidic ocean conditions while the native temperate species will be impacted negatively, possibly resulting in localized extinctions. In chapter 6, I discuss how new techniques and their application aid in understanding the phylogeogaphy of invasive Caulerpa spp. in Australia, paving the way for continued phylogeographic analyses of these problematic species. I have also shown that the response of native and invasive Caulerpa spp. to climate change scenarios indicates that invasive populations of Caulerpa may become more abundant and continue to expand their invasive range in the future. I also identify the limitations of this body of work and the issues encountered in the program of research, and discuss future research possibilities for invasive Caulerpa species.
Thesis (Ph.D.) (Research by Publication) -- University of Adelaide, School of Biological Sciences, 2015.