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Here, Au nanostructure (AuNS) biosynthesis was mediated through ethanolic extract of

Background: The marine red alga Plocamium naturally produces halogenated monoterpenes with varied biological activities. In our continuing efforts to discover new lead compounds for the treatment of HIV/AIDS as well as novel antibacterial compounds, various Namibian Plocamium species have been investigated. Methods: A rare but known compound namely 1E,3R,4S,5E,7Z-1-bromo-3,4,8-trichloro-7- (dichloromethyl)-3-methylocta-1,5,7-triene (1) was isolated from a Namibian Plocamium red alga. The anti-HIV activity of compound 1 was investigated against three HIV enzymes namely, HIV protease, reverse transcriptase and integrase. In addition, compound 1 was also screened for antibacterial activity against selected microbes using the disc diffusion method. Results: Compound 1 demonstrated selective in vitro inhibition against HIV-1 integrase with a 50% inhibition concentration of Conclusion: The results of this study highlight the potential of halogenated monoterpenes from red seaweed as possible leads in the development of new anti-HIV and antimicrobial pharmaceuticals.

The consequences of defensive secondary metabolite concentrations and interspecific metabolite diversity on grazers have been extensively investigated. Grazers which prefer certain food sources are often found in high abundance on their host and as a result, understanding the interaction between the two is important to understand community structure. The effects of intraspecific diversity, however, on the grazer are not well understood. Within a single, localized geographic area, the Antarctic red seaweed Plocamium sp. produces 15 quantitatively and qualitatively distinct mixtures of halogenated monoterpenes ("chemogroups"). Plocamium sp. is strongly chemically defended which makes it unpalatable to most grazers, except for the amphipod Paradexamine fissicauda. We investigated differences in the feeding and growth rates of both Plocamium sp. and P. fissicauda, in addition to grazer reproductive output, in relation to different chemogroups. Some chemogroups significantly reduced the grazer's feeding rate compared to other chemogroups and a non-chemically defended control. The growth rate of Plocamium sp. did not differ between chemogroups and the growth rates of P. fissicauda also did not show clear patterns between the feeding treatments. Reproductive output, however, was significantly reduced for amphipods on a diet of algae possessing one of the chemogroups when compared to a non-chemically defended control. Hence, intraspecific chemodiversity benefits the producer since certain chemogroups are consumed at a slower rate and the grazer's reproductive output is reduced. Nevertheless, the benefits outweigh the costs to the grazer as it can still feed on its host and closely associates with the alga for protection from predation.

Molecular analyses have indicated that several Australian taxa previously identified as the red alga Plocamium cartilagineum do not group with that species as known from its northern hemisphere type locality. One of these species-level genetic groups corresponds precisely with Plocamium pusillum, a species described by Sonder in 1845 based on Preiss specimens from south-western Australia, but regarded as a heterotypic synonym of P. cartilagineum in recent morphology-based treatments. A specimen of P. pusillum in the Melbourne Herbarium (MEL) has been examined and designated as lectotype; its morphology agrees with recently collected specimens included in molecular analyses and is clearly shown to differ from authentic P. cartilagineum. Plocamium pusillum is therefore resurrected and is characterized genetically and morphologically.

Plocamium pusillum Sonder Botanische Zeitung 3: 54 (Sonder 1845). TYPE LOCALITY. — ad oras occidentales Novae Hollandiae. The type specimen was epiphytic on a stem of Amphibolis. LECTOTYPE (here designated). — MEL 1005815 (Fig.2). Note: Sonder (1845) did not cite a specific specimen, but later (1846) gave ‘ Herb. Preiss No. 2613’. This number does not appear on MEL 1005815, which may suggest the existence of additional specimens in other herbaria. However, since we are unaware of any further specimens, we herein lectotypify the species with the single MEL specimen. SPECIMENS EXAMINED (DNA sequence vouchers). — Western Australia, First Rock, S of Penguin Island, Shoalwater Marine Park, 15.II.2011, J.Huisman 15.2.11.1.16 (PERTH 08715351); Cape (Point) Peron, W.A., 3 m depth on algae, G.W.Saunders & K.Dixon (UNB, GWS025286); New South Wales: Yellow Rock, Lord Howe Island, from 15 m depth on rock, G.W.Saunders (UNB, GWS002025); Victoria: The Springs, Point Lonsdale, 4 m depth on rock, G.W.Saunders & L.Kraft (UNB, GWS016698); Norfolk Island, 1 m depth on rock, G.W.Saunders & K.Dixon (UNB, GWS029289). ADDITIONAL SPECIMENS EXAMINED (unsequenced, based on morphology). — Western Australia, Cape Peron, epilithic, 25.II.2021, J.M.Huisman (PERTH 09316647); Eglinton Rocks, 17.V.1996, J.Huisman JH 665 (PERTH 06546757); Burns Beach, drift, 2.IX.1985, R.D.Royce 2562 (PERTH 05163587); Cottesloe, drift, 12.VI.1951, R.D.Royce 1062 (PERTH 04017765); Capel Beach, on rocks between tides, 17.IX.1949, R.D.Royce 368 (PERTH 04017862); Point [Cape] Peron, epiphytic, 28.V.1949, R.D.Royce s.n. (PERTH 04017870); Mushroom Rock, Thomson Bay, Rottnest Island, 16.X.1934, A.Nash s.n. (PERTH 04017838). DISTRIBUTION. — Based on molecular analyses, this species is widely distributed and known from southern Western Australia, Victoria, and New South Wales (Lord Howe Island) and Norfolk Island. HABIT. — Thallus (Fig. 3A) dark red, to 6 cm tall, much branched, attached by a hapteroid holdfast to seagrasses, algae or epilithic (occasionally sand-binding). Primary axes typically sinuous, with lateral branches borne mostly in series of 3 (Fig. 3B), but occasionally in pairs. Lateral branches only slightly more slender than primary axes, therefore often indistinguishable. Lowermost branch in each series simple, straight or curved upwardly, linear with a pointed apex. Axes initially flattened, 250-300 µm broad, 50-100 µm thick (Fig. 3C) but becoming compressed to subterete towards the base, c. 600 µm broad, 400 µm thick (Fig. 3D). Structure pseudoparenchymatous, with large hyaline medullary cells grading abruptly to a cortex of 1-2 cell layers (Fig. 3C, D). Cortical cells with several ovoid to ellipsoid parietal plastids and a spherical central refringent vacuole, the latter only visible in living material (Fig. 3E). REPRODUCTION. — Tetrasporangia are borne in fertile distal segments of upper branches (Fig. 3F), the branches initially simple but eventually dividing and becoming glomerulate. Fertile segments only slightly distended.Tetrasporangia biseriate (Fig. 3G), zonately divided, ovoid/ellipsoidal, 50-60 µm long, 35-45 µm diam. Other reproductive structures not observed., Published as part of Huisman, John M. & Saunders, Gary W., 2021, Resurrection of Plocamium pusillum Sonder (Plocamiaceae, Rhodophyta) from Australia, pp. 231-239 in Cryptogamie, Algologie 20 (14) on pages 236-238, DOI: 10.5252/cryptogamie-algologie2021v42a14, http://zenodo.org/record/7819293, {"references":["SONDER G. 1845. - Nova algarum genera et species, quas in itinere ad oras occidentales Novae Hollandiae, collegit L. Priess, Ph. Dr. Botanische Zeitung 3: 49 - 57."]}

Laboratory studies that test the responses of coastal organisms to ocean acidification (OA) typically use constant pH regimes which do not reflect coastal systems, such as seaweed beds, where pH fluctuates on diel cycles. Seaweeds that use CO2 as their sole inorganic carbon source (non-carbon dioxide concentrating mechanism species) are predicted to benefit from OA as concentrations of dissolved CO2 increase, yet this prediction has rarely been tested, and no studies have tested the effect of pH fluctuations on non-CCM seaweeds. We conducted a laboratory experiment in which two ecologically dominant non-CCM red seaweeds (Callophyllis lambertii and Plocamium dilatatum) were exposed to four pH treatments: two static, pHT 8.0 and 7.7 and two fluctuating, pHT 8.0 ± 0.3 and 7.7 ± 0.3. Fluctuating pH reduced growth and net photosynthesis in C. lambertii, while P. dilatatum was unaffected. OA did not benefit P. dilatatum, while C. lambertii displayed elevated net photosynthetic rates. We provide evidence that carbon uptake strategy alone cannot be used as a predictor of seaweed responses to OA and highlight the importance of species-specific sensitivity to [H+]. We also emphasize the importance of including realistic pH fluctuations in experimental studies on coastal organisms.

The endemic South African red seaweed Plocamium maxillosum (Poiret) Lamouroux produces two unusual isomeric dichlorinated cyclohexenone monoterpenes, plaxenone A and B (1 and 2). The structures of the isolated compounds were determined from spectroscopic data and their absolute configuration was determined by comparison of the experimental and calculated ECD spectra. Compounds 1 and 2 inhibit the growth of MDA-MB-231 breast cancer cells.

International audience; Plocamium Lamouroux is a widespread genus for which 45 species are currently recognized. However, classical taxonomy based only on morphological characters, is problematic within this genus. The use of molecular tools has uncovered cryptic genetic species, mistakenly grouped under the name of mor-phological species that are common and widespread (including the generitype Plocamium cartilagineum (Linnaeus) P.S.Dixon). The aim of this work was to evaluate the species diversity of Plocamium in Southern Chile. For this purpose, three independent molecular markers were sequenced in samples collected from seven populations located between 41°S and 54°S. The species diversity was evaluated using phylogenetic reconstructions and two independent methods for species delimitation (ABGD and GMYC). The outcomes of each method were congruent, suggesting the presence of three species in Southern Chile. One species, named Plocamium sp. 1, is restricted to Punta Guabún, the only locality sampled north of the biogeographic barrier of the 42°S. The other two species, Plocamium sp. 2 and 3 are distributed in sympatry in Patagonia and Tierra del Fuego. The three Chilean species form a clade phylogenetically close to sequences obtained from New Zealand and Australia and a divergence along the coasts of Chile after past transoceanic dispersal is proposed. We propose that divergence in glacial microrefugia could have subsequently happen in the southern part of the coast, this hypothesis being supported by the strong impact of glacial maxima on population dynamics, especially in Plocamium sp. 3; es données moléculaires révèlent la présence de trois espèces de Plocamium Lamouroux présentant un patron de distribution complexe dans le sud du Chili. Quarante-cinq espèces sont actuellement reconnues dans le genre Plocamium Lamouroux, un genre présentant une très ample distribution. Cependant, la taxonomie classique, basée uniquement sur les caractères morphologiques, est problématique au sein de ce genre. L’utilisation d’outils moléculaires a permis de révéler l’existence d’espèces génétiques cryptiques, groupées par erreur sous un même nom, celui d’espèces morphologiques courantes et répandues (y compris l’espèce type du genre Plocamium : Plocamium cartilagineum (Linnaeus) P.S.Dixon)). L’objectif de notre travail était d’évaluer la diversité d’espèces de Plocamium dans le sud du Chili. À cet effet, trois marqueurs moléculaires indépendants ont été séquencés pour des échantillons prélevés dans sept populations situées entre 41°S et 54°S. La diversité en terme d’espèces a été évaluée à l’aide de reconstructions phylogénétiques et de deux méthodes indépendantes de délimitation d’espèces génétiques (ABGD et GMYC). Les résultats des différentes méthodes sont congruents, suggérant la présence de trois espèces dans le sud du Chili. Une espèce, nommée Plocamium sp. 1, est limitée à Punta Guabún, la seule localité échantillonnée au nord de la barrière biogéographique du 42°S. Les deux autres espèces, Plocamium sp. 2 et 3 sont distribuées en sympatrie en Patagonie et en Terre de Feu. Les trois espèces chiliennes forment un clade phylogénétiquement proche de séquences obtenues en Nouvelle-Zélande et en Australie et une divergence le long des côtes du Chili après un évènement historique de dispersion transocéanique passée pourrait expliquer ce résultat. Nous proposons des phénomènes postérieurs de divergence en micro-refuges glaciaires comme moteur de la spéciation en Patagonie et en Terre de Feu. Cette hypothèse est étayée par le fort impact des maxima glaciaires sur la dynamique des populations, en particulier dans le cas de Plocamium sp. 3.

MHC-1 is a halogenated natural product (HNP) produced by the red seaweed Plocamium cartilagineum. MHC-1 concentrations of 550–2700 μg/g dry weight were found in Plocamium collected by divers at Heligoland (Germany). Compared to that MHC-1 concentrations were much lower in samples collected on beaches in Ireland and Portugal. Exposure of leaves of Plocamium to sunlight showed that MHC-1 was readily transformed by hydrodebromination. At Heligoland in March, MHC-1 (δ13C value −45.2‰) was lighter in carbon by ~15‰ compared to the bulk δ13C value (‰) of Plocamium (−30.7‰). Collected at the same time and location at Heligoland, samples of Halichondria and Mastocarpus sp. were richer in carbon (by ~10‰) as Plocamium. However, the δ13C value of MHC-1 in Halichondria (−44.6‰) and Mastocarpus sp. (−42.1‰) was as negative as in Plocamium. This was indirect proof that MHC-1 was produced by Plocamium and then released into the water phase from where it then was bioconcentrated by Halichondria and Mastocarpus sp. In agreement with that, concentrations of MHC-1 in Halichondria and Mastocarpus sp. were much lower than in Plocamium. In addition, a potential isomer of MHC-1 (compound X) was detected in all samples from Heligoland at ~2% of the MHC-1 level.

The aim of this study was to determine suitable extraction solvents for antimicrobial compounds and the antimicrobial activity of two algal species, Plocamium cornutum and Plocamium rigidum collected from the coastline of Namibia. Samples were collected at low tide from the intertidal area of the coastline at Luderitz and Henties Bay. The samples were collected about 5 to 10 cm under water by hand and placed in a sealable polythene bag and refrigerated at -20°C. Dried algae extracts were reconstituted in distilled water, hexane, dichloromethane, ethanol, methanol and chloroform, respectively and tested in vitro for antimicrobial activity using the Kirby Bauer disc diffusion method against 12 pathogens (Escherichia coli, Staphylococcus aureus, Staphylococcus saprophyticus, Pseudomonas aeruginosa, Streptococcus pyogenes, Proteus mirabilis, Listeria monocytogenes, Shigella sonnei, Salmonella species, Enterococcus faecalis, Candida albicans and Staphylococcus epidermidis). Screening confirmed that water extracts showed no activity against all the pathogens as the extracts were insoluble in water. The Plocamium extracts in the remaining solvents showed varying degrees of antimicrobial activity. Both dichloromethane and methanol extracts reconstituted in chloroform showed the greatest activity amongst the five different solvents that were used. Ampicillin (10 µg/ml) showed no antimicrobial activity against S. epidermidis whilst a zone of inhibition of 6.26±0.07 mm was recorded for 10 µg/ml of P. cornutum extract reconstituted in chloroform. An ethanolic extract of P. rigidum showed a zone of inhibition of 6.35±0.25 mm against L. monocytogenes while the standard ampicillin had no activity. Extracts of P. rigidum in ethanol and P. cornutum in chloroform are evidently potential lead candidate antibiotics in vitro against L. monocytogenes and S. epidermidis, respectively. Key words: Antimicrobial activity, Plocamium cornutum, Plocamium rigidum, Listeria monocytogenes.

The antioxidant potential of various marine natural products is well documented. The aim of this study was to evaluate the antioxidant potential of a rare halogenated monoterpene, namely; 1E,3R,4S,5E,7Z-1-bromo-3,4,8-trichloro-7-(dichloromethyl)-3-methylocta-1,5,7-triene (1) for the first time. This compound was isolated from a Namibian red algal Plocamium species. The antioxidant activity of the compound was evaluated using a series of antioxidant assays, namely; 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH), reducing power, nitric oxide (NO) and hydrogen peroxide (H2O2). The compound demonstrated remarkable DPPH, NO and H2O2 scavenging activities with IC50 values of 0.05 ± 0.01, 4.18 ± 0.22 and 5.58 ± 1.11 mM, respectively. The reducing power of the compound increased with an increase in concentration. These results were compared to the absorbance of ascorbic acid, which was used as a standard control in all the antioxidant assays. The results strongly suggest that compound 1 is a promising antioxidant agent with potential commercial applications.

Red algae of the genus Plocamium have been a rich source of halogenated monoterpenes. Herein, a new cyclic monoterpene, costatone C (7), was isolated from the extract of P. angustum collected in New Zealand, along with the previously reported (1E,5Z)-1,6-dichloro-2-methylhepta-1,5-dien-3-ol (8). Elucidation of the planar structure of 7 was achieved through conventional NMR and (&minus, )-HR-APCI-MS techniques, and the absolute configuration by comparison of experimental and DFT-calculated ECD spectra. The absolute configuration of 8 was determined using Mosher&rsquo, s method. Compound 7 showed mild antibacterial activity against Staphylococcus aureus and S. epidermidis. The state of Plocamium taxonomy and its implications upon natural product distributions, especially across samples from specimens collected in different countries, is also discussed.

Breast cancer is the most common cancer type and a primary cause of cancer mortality among females worldwide. Here, we analyzed the anticancer e cacy of a novel bromochlorinated monoterpene, PPM1, a synthetic analogue of polyhalogenated monoterpenes from Plocamium red algae and structurally similar non-brominated monoterpenes. PPM1, but not the non-brominated monoterpenes, decreased selectively the viability of several triple-negative as well as triple-positive breast cancer cells with di erent p53 status without significantly a ecting normal breast epithelial cells. PPM1 induced accumulation of triple-negative MDA-MB-231 cells with 4N DNA content characterized by decreased histone H3-S10/T3 phosphorylation indicating cell cycle arrest in the G2 phase. Western immunoblot analysis revealed that PPM1 treatment triggered an initial rapid activation of Aurora kinases A/B/C and p21Waf1/Cip1 accumulation, which was followed by accumulation of polyploid >4N cells. Flow cytometric analysis showed mitochondrial potential disruption, caspase 3/7 activation, phosphatidylserine externalization, reduction of the amount polyploid cells, and DNA fragmentation consistent with induction of apoptosis. Cell viability was partially restored by the pan-caspase inhibitor Z-VAD-FMK indicating caspase contribution. In vivo, PPM1 inhibited growth, proliferation, and induced apoptosis in MDA-MB-231 xenografted onto the chick chorioallantoic membrane. Hence, Plocamium polyhalogenated monoterpenes and synthetic analogues deserve further exploration as promising anticancer lead compounds., publishedVersion

The genus Plocamium encompasses seaweeds that are widely distributed throughout the world’s oceans, with Plocamium brasiliense found along the tropical and subtropical coasts of the Western Atlantic. This wide distribution can lead to structured populations due to environmental differences (e.g., light levels or temperature), restricted gene flow, and the presence of cryptic species. Abiotic variation can also affect gene expression, which consequently leads to differences in the seaweeds protein profile. This study aimed to analyze the genetic and proteomic profiles of P. brasiliense sampled in two geographically distinct sites on the coastline of Rio de Janeiro state, Brazil: Arraial do Cabo (P1) and Búzios (P2). The genetic profiles of macroalgal specimens from these two sites were indistinguishable as assessed by the markers UPA/23S, rbcL, and COI-5P; however, the protein profiles varied significantly between populations from the two sites. At both sites the ribulose-1,5-biphosphate carboxylase/oxygenase was the most abundant protein found in P. brasiliense specimens. The number of phycobiliproteins differed between both sites with the highest numbers being found at P1, possibly due to water depth. The differences in proteomic profiles of the two nearly identical populations of P. brasiliense suggest that environmental parameters such as light availability and desiccation might induce distinct protein expression, probably as a result of the phenotypic plasticity within this population of seaweed.

The subtidal red alga Plocamium cartilagineum was collected from the Western Antarctic Peninsula during the 2011 and 2017 austral summers. Bulk collections from specific sites corresponded to chemogroups identified by Young et al. in 2013. One of the chemogroups yielded several known acyclic halogenated monoterpenes (2–5) as well as undescribed compounds of the same class, anverenes B–D (6–8). Examination of another chemogroup yielded an undescribed cyclic halogenated monoterpene anverene E (9) as its major secondary metabolite. Elucidation of structures was achieved through one-dimensional (1D) and 2D nuclear magnetic resonance (NMR) spectroscopy and negative chemical ionization mass spectrometry. Compounds 1–9 show moderate cytotoxicity against cervical cancer (HeLa) cells.

As a result of our efforts to identify bioactive agents from marine algae, we have isolated and identified one new halogenated monoterpene 1 [(-)-(5E,7Z)-348-trichloro-7-dichloromethyl-3-methyl-157-octatriene] in addition to three known compounds (2, 3 and 4) from the red alga Plocamium cartilagineum collected by hand from the eastern coast of South Africa. Compound 1 was found to be active as a cytotoxic agent in human lung cancer (NCI-H460) and mouse neuro-2a cell lines (IC50 4 μg/mL). Two of these compounds (3 and 4) were found to have cytotoxic activity in other cell line assays, especially against human leukaemia and human colon cancers (IC50 1.3 μg/mL). None of these metabolites were active as sodium channel blockers or activators. All structures were determined by spectroscopic methods (UV, IR, LRMS, HRMS, 1D NMR and 2D NMR). 1D and 2D NOE experiments were carried out on these compounds to confirm the geometry of the double bonds.

Dye sensitized solar cells assembled using red dyes extracted from Antarctic algae were evaluated. Among all collected algae, the best performances were showed with samples coming from Plocamium hookeri , Delesseria lancifolia and Iridaea obovata . Cells were evaluated using conventional electrochemical techniques and electrochemical impedance spectroscopy. The measured conversion efficiency was lower than 0.04%, using solar simulator with a power of 1 sun, 1.5 AM.

Plocamiun species collected from the Namibian coast display morphological features similar to those of both P. rigidum and P. suhrii which makes identification of these species a difficult task. It has been reported that the major secondary metabolites found in various Plocamium species are unique to each species [1]. In this study GC-MS combined with a retention index (RI) prediction strategy was used for the rapid identification of halogenated monoterpenes characteristic of a particular Namibian Plocatnium species. The RIs of the metabolites were matched with the predicted RIs of halogenated monoterpenes for which similar MS data have been reported for the same species of Plocamium. Based on the identification of the major secondary metabolite, IE,3R,4S,5E,7Z- 1-bromo-3;4,8- trichloro-7-(dichloromethyl)-3-methylocta-1,5,7-triene [2], it was proposed that these Namibian samples are closely related to that of P. suhrii. From. this, it was determined that the proposed P. suhrii specimens collected in Namibia contain four additional metabolites (with molecular formulae C₁₀H₁₆Br₂C₂, C₁₀H₁₁BrCI₄, C₁₀H₉BrCl₆ and an unknown compound) previously not reported in P. suhrii species. In addition, a compound previously identified in South African P. suhrii was not present in the Namibian Plocamium specimens.

Through the current trend for bioprospecting, marine organisms - particularly algae - are becoming increasingly known for their osteogenic potential. Such organisms may provide novel treatment options for osteoporosis and other musculoskeletal conditions, helping to address their large healthcare burden and the limitations of current therapies. In this study, extracts from two red algae – Plocamium lyngbyanum and Ceramium secundatum – were tested in vitro and in vivo for their osteogenic potential. In vitro, the growth of human bone marrow stromal cells (hBMSCs) was significantly greater in the presence of the extracts, particularly with P. lyngbyanum treatment. Osteogenic differentiation was promoted more by C. secundatum (70 µg/ml), though P. lyngbyanum had greater in vitro mineralisation potential. Both species caused a marked and dose-dependent increase in the opercular bone area of zebrafish larvae. Our findings therefore indicate the presence of bioactive components in P. lyngbyanum and C. secundatum extracts, which can promote both in vitro and in vivo osteogenic activity.

The current trend for scientific research is moving towards the production of materials and natural food products to keep overall health of individuals so this research shows methods of extracting natural dyes from green algae (Ulva lactuca L) and red algae ( Plocamium cartilegineum ) & Gelidium sp, and used as colorants and preservatives in processed foods as an alternative to the industrial colors, and as a result they contain antioxidant materials at high is used as a preservative for foods. This study showed that pigments which extracted from green algae her best solvent (acetone aqueous 80%) at wavelength (450 nm ) with an average (.6090 ), followed by ( DMF 100% + Nitrogen liquid ) degree ( -196 ) under zero , when the wavelength (450 nm ), average (.631 ) and be algae in the form of dried, the other side red algae best solvent for the extraction of pigment (Distilled water) to get the red pigment, but to get the green from red algae score the best solvent (DMF 100% + Nitrogen) at the wavelength (450 nm ) average (1.335 ) , followed by ( M.A ) at the same wavelength with an average ( .988 ). The algae are processed before preparing for the extraction of the dye (soak and rinse grinding and sonication of the cells and tissues). The drying process for green was the best and freezing process red is the best Extracting the dye from algae . Been employed in the production of dyes pomegranate jelly from fruit kiwi. Because it is a treasure trove of natural dyes and carotenoids, vitamins and unsaturated fatty acids, protein and dietary fiber. That will affect positively on the overall health of individuals helps clearly to treat (obesity _ diabetes _ osteoporosis _ increase immunity and prevention of cancer ..... etc. all from algae ). Keywords: Microalgae , Seaweeds , Ulva lactuca , Plocamium , Photopigments , solvents, extraction method , Chlorophyll , Carotene .

The family of polyhalogenated monoterpenes from Plocamium counts over a hundred known members. Using glyceraldehyde acetonide as a chiral pool precursor, an enantioselective and divergent strategy was developed that provides a blueprint for the synthesis of many of the small yet complex acyclic members of this family. The broad applicability of this approach is demonstrated with the short (eight-step) synthesis of four natural products and three analogues. These syntheses are the first of any members of the acyclic polyhalogenated Plocamium monoterpenes, and permitted the evaluation of their selectivity against a range of tumor cell lines.

This work presents a taxonomic, floristic and chorological account of the most representative turf-forming species from sand-covered rocks along the Atlantic Iberian Peninsula, including in this Part 2 species belonging to six orders of the Rhodophyta and one of the Phaeophyceae. For each species are provided morphological descriptions, distribution maps, and/or COI-5P sequences, as well as taxonomic notes. The species studied are: Rhodothamniella floridula, Ceramium ciliatum, Erythroglossum lusitanicum, Hypoglossum hypoglossoides, Ptilothamnion sphaericum, Spermothamnion repens, Tiffaniella capitata, Gelidium crinale, G. spathulatum, Pterocladiella melanoidea, Calliblepharis hypneoides, Gymnogongrus griffithsiae, Plocamium maggsiae, Gastroclonium reflexum and Bachelotia antillarum.

Shallow-water communities along the western Antarctic Peninsula support forests of large, mostly chemically defended macroalgae and dense assemblages of macroalgal-associated amphipods, which are thought to exist together in a community-wide mutualism. The amphipods benefit the chemically defended macrophytes by consuming epiphytic algae and in turn benefit from an associational refuge from fish predation. In the present study, we document an exception to this pattern. The amphipod Paradexamine fissicauda is able to consume Plocamium carti- lagineum and Picconiella plumosa, 2 species of sympatric, chemically defended red macroalgae. In previous studies, Plocamium cartilagineum was one of the most strongly deterrent algae in the community to multiple consumers, and was found here to be unpalatable to 5 other amphipod spe- cies which utilize it as a host in nature. Paradexamine fissicauda maintained on a diet of Ploca - mium cartilagineum for 2 mo were much less likely to be eaten by fish than Paradexamine fissi- cauda maintained on a red alga which does not elaborate chemical defenses, or than a different but morphologically similar sympatric amphipod species. Halogenated secondary metabolites pro- duced by Plocamium cartilagineum were identified from tissues of the Paradexamine fissicauda that had eaten it but not those which had eaten the undefended red alga. This indicates that P. fissi- cauda is sequestering the potent chemical defenses of Plocamium cartilagineum for its own use.

Despite recent advances in polar marine biology and related fields, many aspects of the ecological interactions that are crucial for the functioning of Antarctic shallow water habitats remain poorly understood. Although epiphytic diatoms play an essential role in the Antarctic marine food web, basic information regarding their ecology, biodiversity and biogeography is largely unavailable. Here, we synthesise studies on Ross Sea epiphytic diatoms collected during 11 summer Antarctic expeditions between the years 1989/90 and 2011/12, presenting a full list of diatom taxa associated with three macroalgal species (Iridaea cordata, Phyllophora antarctica, and Plocamium cartilagineum) and their epiphytic sessile fauna. Diatom communities found during the three summer months at various depths and sampling stations differed significantly in terms of species composition, growth form structure and abundances. Densities ranged from 21 to >8000 cells mm(-2), and were significantly higher on the surface of epiphytic micro-fauna than on any of the macroalgal species examined. Generally, host organisms characterized by higher morphological heterogeneity (sessile micro-fauna, ramified Plocamium) supported richer diatom communities than those with more uniform surfaces (Iridaea). Differences between epiphytic communities associated with different macroalgae were reflected better in species composition than in growth form structure. The latter changed significantly with season, which was related strongly to the changing ice conditions. A general trend towards an increasing number of erect forms in deeper waters and tube-dwelling diatoms in the shallowest sites (2-5 m) was also observed. This study explores further important and largely previously unknown aspects of relationships and interactions between Antarctic epiphytic diatoms and their micro-and macro-environments.

Red and brown algae have been shown to produce a variety of compounds with chemotherapeutic potential. A recent report described the isolation of a range of novel polyhalogenated monoterpene compounds from the red algae Plocamium corallorhiza and Plocamium cornutum collected off the coast of South Africa, together with the previously described tetraprenylquinone, sargaquinoic acid (SQA), from the brown algae Sargassum heterophyllum. In our study, the algal compounds were screened for anti-proliferative activity against metastatic MDA-MB-231 breast cancer cells revealing that a number of compounds displayed anti-cancer activity with IC(50) values in the micromolar range. A subset of the compounds was tested for differential toxicity in the MCF-7/MCF12A system and five of these, including sargaquinoic acid, were found to be at least three times more toxic to the breast cancer than the non-malignant cell line. SQA was further analysed in terms of its mechanism of cytotoxicity in MDA-MB-231 cells. The ability to initiate apoptosis was distinguished from the induction of an inflammatory necrotic response via flow cytometry with propidium iodide and Hoescht staining, confocal microscopy with Annexin V and propidium iodide staining as well as the PARP cleavage assay. We report that SQA induced apoptosis while a polyhalogenated monoterpene RU015 induced necrosis in metastatic breast cancer cells in vitro. Furthermore, we demonstrated that apoptosis induction by SQA occurs via caspase-3, -6, -8, -9 and -13 and was associated with down-regulation of Bcl-2. In addition, cell cycle analyses revealed that the compound causes G(1) arrest in MDA-MB-231 cells.

A detailed study of the type specimen of Plocamium cartilagineum and other original material of European species of Plocamium revealed that the nomenclatural reorganization proposed by Saunders & Lehmkuhl in 2005 must be revised. The main consequences of the new interpretation are: (1) the use of Plocamium lyngbyanum to name their molecular entity EUR1 (previously considered to be equivalent to P. cartilagineum s.s.); and (2) adopting P. cartilagineum for their molecular entity EUR2, which renders P. subtile Kutzing a taxonomic synonym. Using a combination of morphological, anatomical and molecular information (barcoding), we conclude that the colour and consistency of the thallus, the number of ramuli per series, the morphology and arrangement of the tetrasporangial stichidia, the length of the tetrasporangia, and the type of habitat are the most reliable characters of classical taxonomy for discriminating between the species of Plocamium occurring in northern Europe.

Differentiating between different Plocamium species of marine algae is not a trivial task. However, a literature review reveals that each species of Plocamium has a major and minor metabolite that is unique to a particular Plocamium species being investigated. Knowledge about the chemotaxonomy of these unique major and minor metabolite standards therefore enables the potentially rapid identification of Plocamium species by means of either 1H NMR or GC-MS analysis of crude Plocamium extracts.

The chemical composition of green Codium tomentosum Stackhouse and red Plocamium cartilagineum (Linnaeus) P.S. Dixon seaweeds from the Atlantic Ocean surrounding Portugal was studied. For the first time, the profile of organic acids was analysed in these matrices: seven and four organic acids were detected in green and red species, respectively. In P. cartilagineum these compounds were present in vestigial amounts, whilst C. tomentosum exhibited a higher content, with oxalic acid being the main compound. Phenolics, UV-absorbing compounds, were absent in both species. Volatiles profile was also determined for the first time and a total of 41 compounds were identified, which included alcohols, aldehydes, esters, halogenated compounds, ketones, monoterpenes (namely terrestrial ones), norisoprenoid derivatives, amongst others. Norisoprenoid derivatives and aldehydes were predominant. The main volatiles in green and red seaweeds were limonene and benzophenone, respectively. Additionally, both species revealed considerable antioxidant activity against both reactive oxygen (superoxide radical) and reactive nitrogen (nitric oxide) species, in a concentration-dependent manner. info:eu-repo/semantics/publishedVersion

We investigated species composition and variation of benthic marine algae between 2003 and 2006 at Dokdo on the East Sea. The total number of benthic algae species identified was 96, which included 15 Chlorophyta, 30 Phaeophyta, 50 Rhodophyta and 1 Spermatophyta species. The representative species in this study were Ulva pertusa, Caulerpa okamurae, Codium adhaerens, C. frgile, Undaria pinnatifida, Ecklonia cava, Eisenia bicyclis, Dictyopteris undulata, Padina arborescens, Sargassum horneri, Hildenbrandtia rubra, Lithophyllum okamurae, Amphiroa dilatata, Corallina officinalis, C. pilulifera, Prionitis cornea, Grateloupia elliptica, Plocamium telgairiae, Chondrus ocellatus, Chondracanthus intermedia, Chondria crassicaulis, Polysiphonia morrowii, Melobesioidean algae and Phyllospadix sp. Wet weight biomass according to various depths ranged between 1,094.8 to during the study period. Mean biomass at the investigated sites was greater in the 15m depth range than in the 5 and 10m depths. Vertical distribution was characterized by Ulva intestinalis, U. linza, Endarachne binghamiae, Bangia atropurpurea, Gloiopeltis furcata and Chondria crassicaulis at intertidal zone, Amphiroa dilatata, Corallina pilulifera, Gelidium amansii, Eisenia bicyclis and Ecklonia cava at 2m depth, Ecklonia cava, Eisenia bicyclis, Padina arborescens, Undaria pinnatifida and Sargasum horneri at 5m depth, Ecklonia cava, Sargassum horneri and Padina arborescens at 10m depth, Ecklonia cava, Myagropsis myagroides, Padina arborescens and Sargassum horneri at 15m depth. The R/P, C/P and (R+C)/P value were 1.67, 0.50 and 2.17, respectively.

A bacterial strain able to produce κ-carrageenase, designated WZUC10, was isolated from a live specimen of the red alga Plocamium telfainae collected in the East China Sea. The phylogenetic evidence and phenotypic features indicate that this strain belongs to the genus Pseudoalteromonas. WZUC10 requires NaCl for growth and κ-carrageenan to induce κ-carrageenase synthesis; galactose and lactose do not induce it. The optimal growth temperature is 23∼27°C. The secreted enzyme, which has a molecular mass of 45 kDa, breaks down κ-carrageenan into κ-neocarratetraose sulfate and larger oligosaccharides with a repeating β-D-Galp4S-(1→4)-α-D-AnGalp structure, but cannot degrade κ-neocarratetraose sulfate or κ-neocarrahexaose sulfate into κ-neocarrabiose sulfate. The enzyme retains 90% of its activity after 2 h at 40°C and is completely inactivated after 7.5 min at 70°C. The enzyme’s optimal temperature is 30°C and its optimal pH is 7.5. The enzyme-catalyzed reaction follows Michaelis-Menten kinetics, with the Michaelis constant (K m) and the turnover number (k) being 0.015 mM and 125 s−1, respectively. WZUC10 produces 50 U/mL κ-carrageenase after cultivation at 25°C for 35 h on a medium containing 80 g/L glucose, 5 g/L corn steep liquor, 3 g/L κ-carrageenan, and 15 g/L NaCl. κ-Neocarratetraose sulfate was prepared simply with precipitation by ethanol:water (5:1, v/v).

Introduction: Over the last decade HPLC-NMR has become a robust analytical technique that has been applied to a wide range of studies, particularly plant extracts. There have been only a few applications of the use of HPLC-NMR to profile marine natural product extracts and no studies involving marine algae. The marine alga selected for this study belongs to the genus Plocamium, which is a well known source of polyhalogenated monoterpenes. Objective: To chemically profile the marine alga P. mertensii, using a combination of on-line (HPLC-NMR) and off-line approaches. Methodology: P. mertensii was extracted with 3:1 methanol-dichloromethane and subsequently partitioned into dichloromethane and methanol-soluble fractions. The methanol partition was exclusively profiled by HPLC-NMR (on-flow, stop-flow and time-slice experiments) whilst the dichloromethane partition was investigated by conventional isolation and purification procedures. Results: HPLC-NMR analysis of the methanol partition partially identified the presence of the major compounds 7, 13, 27 and 37, the structures of which were unequivocally elucidated by off-line characterisation of the dichloromethane partition. Two additional minor metabolites (3 and 8) present in the dichloromethane partition were only tentatively identified as these co-occurred in a mixture with compounds 7 and 13. As a result of this study a number of chemical shift reassignments were made for compound 37. Conclusion: This is one of the few reports describing the application of HPLC-NMR to rapidly proftle or dereplicate a marine organism and the first application of HPLC-NMR to successfully profile the chemistry of a marine alga.

The shallow kelp forest at Santa Catalina Island, California (33.45 N, i118.49 W) is distinguished by several canopy guilds ranging from a Xoating canopy (Macrocystis pyrifera), to a stipitate, erect understory can- opy (Eisenia arborea), to a short prostrate canopy just above the substratum (Dictyopteris, Gelidium, Laminaria, Plocamium spp.), followed by algal turfs and encrusting coralline algae. The prostrate macroalgae found beneath E. arborea canopies are primarily branching red algae, while those in open habitats are foliose brown algae. Densi- ties of Corynactis californica, are signiWcantly greater under E. arborea canopies than outside (approximately 1,200 versus 300 polyps m i2 respectively). Morphological diVerences in macroalgae between these habitats may aVect the rate of C. californica particle capture and serve as a mechanism for determining polyp distribution and abun- dance. Laboratory experiments in a unidirectional Xume under low (9.5 cm s i1 ) and high (21 cm s i1 ) Xow speeds examined the eVect of two morphologically distinct macro- algae on the capture rate of Artemia sp. cysts by C. califor- nica polyps. These experiments (January-March 2006) tested the hypothesis that a foliose macroalga, D. undulata, would inhibit particle capture more than a branching alga, G. robustum. G. robustum, found predominantly under the E. arborea canopy did not aVect particle capture. However, D. undulata, found predominantly outside of the canopy, inhibited particle capture rates by 40% by redirecting parti- cles around C. californica polyps and causing contraction of the feeding tentacles. These results suggest that the mor- phology of Xexible marine organisms may aVect the distri- bution and abundance of adjacent passive suspension feeders.