Marine Macro Algae

Flora algal da costa portuguesa O litoral português, com um total de 830 quilómetros comporta, separados por grandes areias, extensões rochosas, muitas delas ricas em algas. Grande parte das zonas costeiras encontram-se muito expostas à acção do mar (Lewis, 1964) e as algas do patamar médiolitoral encontram-se sobretudo no horizonte inferior, delimitado pelo nível mínimo da maré baixa . Ardré (1970;, que estudou exaustivamente a flora algal portuguesa no final da década de 60 (do século passado), identificou e descreveu 246 espécies de Rhodophyceae, 98 Phaeophyceae e 60 Chlorophyceae, números que não se alteraram significativamente desde então .

Çok hücreli ökaryotik organizmalardan olan makro algler denizlerin önemli canlı kaynaklarından biridir. Deniz yosunu olarak da adlandırılan bu canlılar zengin içerikleri nedeniyle,  gıda, fikokolloid, ziraat, eczacılık, tıp ve enerji gibi birçok endüstriyel alanda değerlendirilmektedir. Dünya genelinde, 43 ülkede toplam 291 makro alg türü kullanılmaktadır. Üretilen 28 milyon ton deniz yosunun 800.000 tonluk kısmı doğadan toplanırken % 94’ü yetiştiricilik yoluyla elde edilmektedir. Deniz yosunları endüstrisi, dünya ekonomisine yaklaşık 5 milyar USD katkı sağlamaktadır. Ülkemizde ise, makro alglerle ilgili olarak akademik düzeyde üretim çalışmaları bulunmasına rağmen ticari üretime bir türlü geçiş yapılamamıştır. Alg üretimine yönelik üniversite – sanayi işbirliği projeleri oluşturularak ülkemizin de bu büyük pazarda bir an önce yer alması sağlanmalıdır.

Kegiatan Manta Explore ini dilaksanakan dengan tujuan menginventarisasi ekosistem pesisir yang terdapat di Pulau Biawak. Pengamatan berlangsung pada tanggal 24 - 27 Mei 2012. Berdasarkan hasil pengamatan, diketahui bahwa jenis mangrove Rhizophora stylosa ditemukan hampir diseluruh Pulau Biawak. Lamun yang ditemukan meliputi jenis Enhalus sp. dan Halophila sp. Makro alga yang ditemukan sebanyak lima jenis yaitu Halimeda sp., Sargassum sp., Caulerpa sp., Neomeris sp. dan Padina sp. Sedangkan kondisi terumbu karang di Pulau Biawak didominasi oleh Hard Coral yang terdiri dari kategori Acropora dan Non Acropora, dimana penutupan kategori ini berkisar antara 17,5 - 50 % dari setiap stasiun pengamatan. Kualitas perairan di Pulau Biawak sebagai factor pendukung memiliki kesesuaian untuk hidup dan tumbuhnya hewan karang dan organisme aquatik lainya begitupun bagi pertumbuhan mangrove.

The main purpose of the study was to determine the distribution and abundance of seagrasses and marine invertebrates in three sites of Cogtong bay. The method used was based on Seagrass-watch protocol for monitoring intertidal seagrasses habitats (McKanzie, 2001). Percentage cover of seagrass was measured and evaluated through the Systematic Transect – Quadrat (TQ) method. It was observed that in the three stations, sand has large portion of 76.78% if compared to seagrass cover which only have 23.22% in the entire 150 m 2 area. For marine invertebrates, it was observed that the most dominant species in the bay area was sea urchin with a total of 168 individuals, followed by Pyrola sp. with 31, third by fenestrate top shells and sponge with 15 individuals, and the least dominant marine invertebrates was spider conch with 4 individuals found as observed in Lumislis islet, Mabini, Bohol.

Phenolics, sometimes called polyphenolic compounds, are present in a variety of terrestrial and marine plants. They are utilized as important components of both human and animal diets for their antioxidant capacity. More than 8000 phenolic structures are currently known (Bravo 1998). To date, most polyphenols isolated from marine sources and referenced in the literature are of macroalgal origin (Li et al. 2011). The structures of natural polyphenols vary from simple molecules, such as phenolic
acids and other simple polyphenolic compounds, to the more complex phlorotannins, which consist of polymeric structures made up of units of phloroglucinol (1,3,5-trihydroxybenzene), typically isolated from marine brown algae or Phaeophyceae (Harborne 1980; Ragan & Glombitza 1986). Polyphenols exhibit a wide range of biological effects as a consequence of their antioxidant properties. The relatively high concentration of phenolic compounds in marine algae species contributes
to their antioxidant properties, which can be of benefit in reducing oxidative reactions deleterious to health. Oxidative stress in the human cell occurs during disease conditions or when optimal nutrition is lacking. Under these circumstances, the so-called “reactive oxygen species” (ROS) are available to initiate lipid peroxidation and damage to other biomolecules. Current evidence strongly supports the contribution of phenolic compounds to the prevention of cardiovascular diseases (CVDs) and cancers,
and suggests their role in the prevention of neurodegenerative diseases and diabetes mellitus (Urquiaga & Leighton 2000). This chapter reviews some of the chemical and biological properties of marine algae phenolics as natural antioxidants and discusses their protective effects in biological systems and their potential
activities in food products.

Ulva lactuca (commonly known as sea letuce) is a green sea weed which dominates Green Tides or algae
blooms. Green Tides are caused by excess nitrogen from agriculture and sewage outfalls resulting in
eutrophication in shallow estuaries. Samples of U. lactuca were taken from the Argideen estuary in West
Cork on two consecutive years. In year 1 a combination of three different processes/pretreatments were
carried out on the Ulva. These include washing, wilting and drying. Biomethane potential (BMP) assays
were carried out on the samples. Fresh Ulva has a biomethane yield of 183 L CH4/kg VS. For dried, washed
and macerated Ulva a BMP of 250 L CH4/kg VS was achieved. The resource from the estuary in West Cork
was shown to be sufficient to provide fuel to 264 cars on a year round basis. Mono-digestion of Ulva may
be problematic; the C:N ratio is low and the sulphur content is high. In year 2 co-digestion trials with
dairy slurry were carried out. These indicate a potential increase in biomethane output by 17% as compared
to mono-digestion of Ulva and slurry.

Naturally endowed with a coastline of about 8,000 Km represented in a wide range of ecosystems like estuaries, mangroves, backwaters, salt marshes, sandy beaches, rocky coasts, coral reefs, and many such variations in ecosystem diversity, India is also predictably blessed with a treasure of marine biotic resources. A conservative estimate of about 80% of all such resources is found in the coastal zones. Such diversity is attributed to the complex habitats created by the dominant benthic primary producers along with the phytoplankton of the productive shallow waters, further stimulated by terrestrial inputs and upwelling incidents. The primary producers that belong to the heterogeneous regions. Distribution patterns and regional assemblage composition of algal species worldwide have been important fields of study. Recent studies suggest that energy and habitat area play an important role in determining the present-day distributional patterns observed for marine algae along with the role of historical processes. A discussion on the utilization status of such resources in India starts on the note that India has quite a phenomenal resource base. The three most important contributors to such resources include the red algae, brown algae and green algae. The current paper deals with a review and discussion of the extent of marine resources in India, their use and sustainability issues and a special note on the algal resources of Sundarbans and the potential use patterns of the same.

The long geographic isolation of New Zealand, an archipelago with a large latitudinal range (29°to 54°S) and an extensive coastline, has resulted in a high level of endemism in both land and coastal marine flora. The genus Porphyra in NZ is represented by 5 epiphytic species and a number of epilithic species, many of which are undescribed. Systematic studies aimed at understanding variation inmorphology and life history are underway, and have led to the description of a number of new species. The present study uses sequence data from the18S rDNA locus to investigate genetic variation in New Zealand Porphyra. Sequences have been fully determined for 10 epilithic species. A subset of these data has been shown to be sufficient to distinguish established taxa and to identify new entities. Our data indicate that New Zealand harbours at least 12 epilithic species of Porphyra, establishing the NZ coastline as a repository of diversity for this genus. Phylogenetic trees based on division in complete 18S rDNA sequence data show a deep division in the genus that is not obviously correlated with existing morphological characters, and indicate that representatives of the New Zealand flora have undergone long reproductive isolation.

A common symptom of eutrophication in temperate estuaries is the proliferation of ephemeral, floating macroalgae. Information on the effects of blooms on underlying assemblages mostly originates from non-vegetated intertidal and subtidal habitats. Blooms also often settle in large aggregations over seagrasses, where they decompose. To test hypotheses concerning the effect of dense mats on underlying assemblages of benthic invertebrates within a seagrass meadow, biomass of the green macroalga Enteromorpha intestinalis was experimentally manipulated in the Tuggerah Lakes estuary, New South Wales, Australia. Algae, equivalent to a naturally occurring bloom (~4.5 kg wet wt m -2 ), were added to caged plots (1 m 2 ) at 2 sites in the seagrass meadow. After 3 mo, the E. intestinalis population began to decompose in the treatment plots and in shallow habitats adjacent to the foreshore. Dramatic declines in the biomass of seagrass and components of the infauna were detected in plots containing decomposing macroalgae. The results have implications for managing estuaries, since assemblages of seagrasses and macrobenthic organisms are considered to be important in nutrient-cycling and food-webs.

Our research includes biochemical study, evaluation of anti-oxidant activities and heavy metals contamination in Ulva lactuca and Cystoseira stricta collected at the site of Sidi El Adjel (Mostaganem). We registered a total phenol content in Ulva lactuca and Cystoseira stricta were 0.383 5.43 mg EAG/g MS respectively. The polyphenols contamination caused the significant antioxidant effects on DPPH. The yield of crude extract for petroleum ether were 2 and 8.8% in Ulva lactuca sp and Cystoceira stricta, whereas it were 7.9 and 2.07% for the methanol respectively. We noted the ability of studied algae extracts to reduce the DDPH. A low total lipid content was 4 and 5.5% in Cystoseira stricta and Ulva lactuca respectively, whereas the appreciable crude protein contents wad 21 and 30.6%. Chemical analyzes of our algae reveal levels estimated at 22% in Ulva lactuca sp, and 19.4% in Cystoseira stricta. We estimated high zinc concentrations, which were 187.59 and 298.64 ppm. PS in Cystoseira stricta and Ulva lactuca respectively.

Цемесская бухта с прилегающей частью открытого моря известна как важный рыбопромысловый район. Ежегодное число туристов, посещающих г. Новороссийск составляет не менее 1 млн. чел., что позволяет считать город не только промышленным, но и курортным центром Черноморского побережья России и подчеркивает особую важность мониторинга экологической обстановки в аквальных ландшафтах. Разработка месторождения мергеля и производство портландцемента в г. Новороссийске представляют экологическую угрозу для бухты. Биогеохимическое исследование 150 проб водорослей выявило участки акватории с неблагоприятной экологической обстановкой. Максимальные содержания большей части элементов отмечены в пробах цистозиры (Cystoseira barbata), характеризующих центральную часть бухты – побережье г. Новороссийска. Аквальные ландшафты на этих участках испытывают наибольшее воздействие осажденных из воздуха поллютантов, поступающих с водным стоком. Наименьшие концентрации металлов характерны для проб, отобранных в зонах влияния биогенных ландшафтов лесов, однако и на этих участках прослеживается воздействие выбросов цементного завода и иных промышленных предприятий. Биогеохимический мониторинг 1999–2009 гг. выявил общую тенденцию к уменьшению средних содержаний большинства рассмотренных элементов в период до 2004 г. и возрастание содержаний к 2009 г. При наличии общей тенденции, аккумуляция в водорослях различных металлов имеет свои особенности. При этом наиболее низкие средние содержания элементов в пределах акватории города постоянно остаются на уровне, превышающем содержания, характерные для водорослей в зонах влияния биогенных лесных ландшафтов.

Ключевые слова: Чёрное море; биогеохимия; водоросли; тяжелые металлы.
Abstract
Tsemes Bay with adjacent open sea water area is known as an important fishing region. The annual number of tourists visiting Novorossiysk city is at least 1 million people. This allows us to consider the city as an industrial and resort centre of Russian Black Sea coast and emphasises the special importance of environmental conditions’ monitoring in aquatic landscapes. Marl mining and production of Portland cement in Novorossiysk constitute the environmental threat to the bay. Biogeochemical research of 150 algae samples identified the water areas with adverse environmental conditions. The maximum content of most part of chemical elements was observed in Cystoseira barbata samples, characterising the coast of Novorossiysk in central part of the bay. Aquatic landscapes in these areas experience the greatest impact of pollutants arriving from the air and coming with the water drain. The lowest concentrations of metals are typical for samples taken in the zones of biogenic forest landscapes’ influence, but even in these areas the impact of cement plant and other industrial enterprises emissions can be traced. Biogeochemical monitoring held in 1999–2009 revealed a general trend toward a decrease of the average elements contents in the period up to 2004, and the increase of contents by 2009. At presence of a general trend, the accumulation of various metals in algae has its own characteristics. At the same time, the lowest average concentrations of elements within the city water area constantly remain at the level exceeding the content in algae growing in the areas of biogenic forest landscapes’ influence.

Keywords: Black sea; biogeochemistry; algae; heavy metals.

Ulva lactuca, a green seaweed, accumulates on beaches and shallow estuaries subject to eutrophication.
As a residue, and a macro-algae, it is a source of sustainable third generation biofuel. Production of biomethane
from mono-digestion of U. lactuca, however is problematic due to high levels of sulphur and low
ratios of carbon to nitrogen. Fresh and dried U. lactuca were continuously co-digested with dairy slurry at
ratios of 25%, 50% and 75% (by volatile solid content) in 6 number 5 L reactors for 9 months. The reactors
digesting a mix with 75% U. lactuca struggled to reach stable conditions. Volatile fatty acid levels of
14,000 mg l1 were experienced. The levels of ammonia increased with percentage U. lactuca in the
mix. Optimum conditions were observed with a mix of 25% fresh U. lactuca and 75% slurry. A yield of
170 L CH4 kg1 VS was achieved at an organic loading rate of 2.5 kg VS m3 d1.

Coastal aquaculture is a globally expanding enterprise. Currently, 1200 salmon farms operate in coastal Norway, yet their capacity to aggregate and subsequently modify wild fish distributions is poorly known. Aggregations of wild fish at 9 farms and 9 control locations were counted on 3 separate days in June to August 2007. On each sampling occasion, 6 counts were made at 5 distinct depth-strata at each farm and control location. Wild fish were 1 to 3 orders of magnitude more abundant at farms than at control sites, depending on the location. Gadoid fish (Pollachius virens, Gadus morhua and Melanogrammus aeglefinus) dominated farm-associated assemblages and were present across a wide range of sizes, from juveniles to large adults. Estimated total farmaggregated wild fish biomass averaged 10.2 metric tonnes (t) per farm across the 9 farms (range: 600 kg to 41.6 t). Applied across the geographical range of Norway's 1200 salmon farms, our estimates indicate that salmon farms attract and aggregate over 12 000 t of wild fish into a total of just 750 ha of coastal waters on any given day in summer. Possible consequences of these persistent, substantial aggregations of wild fishes at farms include a heightened potential for the transfer of pathogens from salmon farms to wild fish and among adjacent salmon farms, and altered availability of wild fish to fisheries. Restrictions on fishing in the immediate surrounds of salmon farms may avoid farms acting as ecological traps, particularly for species with depressed populations such as G. morhua, which are highly attracted to farms.

– Mangrove macroalgae produce substantial proportion of biomass, which contributes to the coastal ecosystems. Relatively less is known for the seasonal variation in the occurrence and biomass of mangrove associated macroalgae. Consequently, mangrove macroalgae epiphytic on the pneumatophores of Avicennia marina (Forsk.) Vierh., were sampled from the Miri estuary of Sarawak during the four seasons of Malaysia namely southwest monsoon, northeast monsoon, and two inter-monsoons to elucidate seasonal variation in the occurrence and biomass production of macroalgae. Over the sample period, 11 species of mangrove macroalgae were identified from 6 genera. Six of these species such as Caloglossa leprieurii (Montagne) J.Agardh, C. adhaerens R.J.King & Puttock, C. stipitata E.Post, C. ogasawaraensis Okamura, Bostrychia kelanensis Grunow and Dictyota sp. were found to be common in each sample time. Considering four seasonal samples, maximum frequency of occurrence was observed for C. ogasawaraensis (66 ± 10%) and maximum biomass was observed for B. kelanensis (248 ± 95 g m –2). Marked seasonal variations were observed in the frequencies of occurrence and the biomass for the most of the dominant macroalgal species. To the best of our knowledge this is the first time to report the seasonal pattern data for occurrence and abundance of macroalgae from the mangrove systems of Malaysia.

Home and public sea aquaria are becoming more and more popular worldwide. Aquaria species are selected for their aesthetic appeal in terms of color, shape or behavior. In Brazil, most species are imported from remote places, usually tropical areas around the world. Water discarded from aquaria often includes organisms, or their propagula, that may become locally established. There have been extensive discussions concerning the vectors of species dispersion from their native areas, which includes ornamental aquaria. In order to evaluate the potential of local aquaria as a source of non native macro algae, we surveyed sea-aquaria shops and exhibition aquaria in São Paulo State. Thirty eight species of seaweeds were isolated in the aquaria surveyed. Among them, six have not been recorded from Brazil and nineteen were not reported for São Paulo littoral, including Caulerpa scalpelliformis var. denticulata the only species that so far deserves being designated as invasive in Brazil. The present paper should alert environmental agencies and aquaria shops about the risk of involuntarily introducing non-native species through aquariophyly.

Phytomyxids (Phytomyxea) are obligate endosymbionts of many organisms such as algae, diatoms, oomycetes and higher
plants including seagrasses. Despite their supposed significant roles in the marine ecosystem, our knowledge of their marine
diversity and distribution as well as their life cycles is rather limited. Here we describe the anatomy and morphology of several
developmental stages of a phytomyxid symbiosis recently discovered on the petioles of the alien seagrass Halophila stipulacea
at a locality in the southeast Aegean Sea. Its earliest stage appeared as whitish spots already on the youngest leaves at the apex of
the newly formed rhizomes. The infected host cells grew in volume being filled with plasmodia which resulted in the formation
of characteristic macroscopic galls. The plasmodia eventually cleaved into spores and in the final stage, the dark brown to black
galls contained mature resting spores often arranged in duplexes and possessing thick verrucous outer walls. Based on its anatomical
and morphological features the phytomyxid was identified as Plasmodiophora cf. halophilae. Little is so far known about the
origin and eco-physiological functioning of this rare symbiosis. However, seemingly similar infection patterns were reported in
1913 on Halophila ovalis from Java and in 1995 on H. stipulacea from Sicily. Since H. stipulacea is of Indo-Pacific origin and no
phytomyxid infection was observed on the co-occurring autochthonous seagrasses Cymodocea nodosa or Posidonia oceanica, we
hypothesize that this phytomyxid might have co-migrated into the Mediterranean through the Suez Canal.

Metallic nanoparticles have been traditionally synthesized using wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this research, we present a simple and ecofriendly biosynthesis of Ag nanoparticles using Ulva fasciata crude ethyl acetate extract as reducing and capping agent. The bionanoparticle characterized with UV-vis Spectroscopy, FTIR, XRD, SEM and EDX. Characterization reveals that the nanoparticles are crystalline in nature, spherical in shape and poly-dispersed with size ranging from 28 to 41 nm. The alkyne group (3424.30 cm -1 ) of U. fasciata crude ethyl acetate extract shifted and reduced the AgNO 3 . GC-MS analysis revealed the presence of 1-(Hydroxymethyl)-2, 5, 5, 8A-tetramethyl decahydro-2napthalenol as reducing agent and hexadecanoic acid was found to be a stabilizing agent. Ulva fasciata based bionanoparticles inhibited the growth of Xanthomonas campestris pv. malvacearum (14.00±0.58 mm Zone of inhibition), with a Minimum Inhibitory Concentration of 40.00±5.77µg/mL. The study shows that U. fasciata crude ethyl acetate extract could be used as a reducing agent for simple ecofriendly synthesis of silver nanoparticles. However, more studies are essential before recommending them for disease management.

Amphiroa fragilissima (Linnaeus) Lamouroux belongs to the family Corallinaceae collected from Tharuvaikulam coast, Gulf of Mannar coastal region, Tamilnadu was analyzed for its proximate and Elemental composition. In our present investigation the proximate composition(in %)of Carbohydrate(18.

The present study investigated the antimicrobial and antioxidant activities as well as the chemical composition of the methanolic extracts of Spirogyra setiformis and Navicula spp. found in Nigerian waters. The minimum inhibitory concentration (MIC) of the methanolic extracts of the algae were determined against 7 clinical isolates (Enterococcus faecalis, Staphylococcus aureus ATCC 25923, Bacillus cereus, Klebsiella pneumoniae, Salmonella typhi, Escherichia coli ATCC 25922 and Candida albicans) using the broth dilution method. The antioxidant activity of the algae extract was assessed using 1,1-diphenyl-1-picrylhydrazyl, nitric oxide and reducing power assays. The volatile constituents of the extracts were also analysed using GC–MS. The results revealed that the S. setiformis extract inhibited all the clinical isolates except S. typhi and C. albicans while Navicula spp. had inhibitory effects on all the test isolates. The MIC values of the algae extracts varied between 2.0 mg/L and 10.0 mg/L. Both extracts showed potent free radical scavenging activities evidenced in DPPH, nitric oxide and reducing power assays. A total of 16 and 11 volatile compounds were obtained from S. setiformis and Navicula spp., respectively. The major component in S. setiformis was 11,14,17-methyl ester eicosatrienoic and trans-geranyl geraniol in Navicula spp. These findings suggest that these indigenous algae species could be good sources of antimicrobial and antioxidant agents.

This work reports the occurrence of the introduced alga Caulerpa ollivieri Dostál, 1929 in the Southern Gulf of Mexico off the northern coast
of the Yucatan Peninsula, Mexico. In 2010, a specimen was collected off the Dzilam de Bravo, and additional specimens were detected in at
least four localities along the coast. These records extend the distribution of C. ollivieri 800 km to the south; it was first recorded off the
Tampa Bay in Florida (USA) in 1968 and subsequently in The Bahamas. Further work is now needed to determine the impact this introduced
alga may have on the native benthic community.

Gelidium allanii Chapman is endemic to northern New Zealand with a highly localised distribution. This species has remained little known, having been collected from only one locality for more than 40 years. We compare this species with other New Zealand members of the Gelidiaceae, in particularGelidium caulacantheum andPterocladia capillacea, presenting new data on morphology, distribution and agar chemistry to more fully characteriseG. allanii.G. allanii possesses a very distinctive, highly pyruvated agar. New Zealand records of two Australian speciesG. australe andG. asperum are examined and it is concluded that there is no evidence for their occurrence in New Zealand.

In the Present investigation GC-MS analysis was done on marine red seaweed Halymenia dilatata in order to confirm its rich bioactive compounds that are economically important as potential fish feed. The results confirmed the presence of compounds like Hydroperoxide, 1-methylbutyl, Nonyl trifluoroacetate, Decane 2,2,3-trimethyl, Acetyl valeryl, Dodecyl trifluoroacetate 2-Bromo dodecane and 3 Ethoxy-1,1,1,5,5,5-hexamethyl-3 trimethyl. It was found that Hydroperoxide and Acetyl valeryl were the compounds that benefit the fishes in their growth and survival.

Metal pollution in the marine coastal line environment is an important topical issue in the context of ecological disturbance. The concentration of nine trace elements: Cu, Co, Ni, Cr, Mn, Zn, Cd, Pb, and Fe was determined in water, sediments and the green alga Ulva lactuca (L.), which collected from several sites at three main area (Suez Gulf, Aqaba Gulf and Suez Canal). The abundance of metal concentrations in algae samples was in the following order: Fe> Zn> Mn> Pb> Cu> Ni> Co> Cr> Cd, Fe> Mn>Zn> Pb> Cu> Ni> Co> Cr> Cd, and Fe> Mn>Zn> Cu> Pb> Ni> Co> Cr> Cd in Suez Gulf, Aqaba Gulf, and Suez Canal respectively. The variations at this order of abundance were according to the different in activities and metal sources in these different areas. The high uptake of metals in green alga Ulva lactuca suggested that this alga may be used as potential biomonitors for heavy metal pollution. The BCF value of metals in the algae/water was significantly higher than those of algae /sediments. The pollution indicator of Contamination Factor (BCF) was calculated to determine the degree of metal pollution in the marine coastline and the contribution of anthropogenic influence. Significant (p≤0.05) inter-elemental positive-correlations were observed between most studied metals, as well as negative-correlations between a few of them. Overall, the comparison of heavy metal contents with seawater and sediment samples in the Ulva species showed that U. lactuca is a suitable plant for biomonitoring studies.

Low nitrogen availability is one of the major environmental factors limiting macroalgal growth in temperate marine ecosystems. Macroalgae have overcome the fluctuating nature of nitrogen supply via adjustments to their life-history (e.g. opportunistic versus perennial) and/or their morphophysiology (e.g. type of growth, use of reserves). Fast-growing species dominate when nutrients are elevated but are typically absent in nutrient-poor systems; Macrocystis pyrifera, however, is an exception because it is a perennial species as well as fast-growing. Although its nutrient demands are inherently high (due to its size and productivity), it remains a cosmopolitan species even when nitrogen concentrations are low. The primary objective of this collective work is to refine current knowledge on how the ecophysiology of Macrocystis helps mitigate nitrogen limitation. This is investigated within small communities (i.e. intra-bed mass-transfer) and also within individuals (i.e. endogenous nitrogen use and storage).

Nitrogen uptake is enhanced by increased rates of water mass-transfer, which is largely dictated by water flow. Macrocystis beds modify their physical environment so that flow rates are reduced in the bed's interior. To better understand how macroalgae influence mass-transfer rates within kelp beds, the architecture of a model kelp bed is described, highlighting dominant canopy and subcanopy species. These biogenic structures significantly influenced the rates of masstransfer throughout the bed – rates were highest at the exterior edge and at the surface of the bed, decreasing towards the interior and with depth. Growth and tissue chemistry (e.g. pigmentation, soluble nitrate) of Macrocystis paralleled the intra-bed variability in mass-transfer. This work also provides evidence that the influence of mass-transfer on nitrogen acquisition is a particularly important mechanism when ambient nitrogen is limiting.

Growth is described as Macrocystis' first and primary response to nitrogen enrichment. Enrichment studies, however, typically fertilise experimental kelp beyond naturally occurring nitrogen concentrations and the nuances in physiological responses to realistic nitrogen enhancement (e.g. upwelling) are likely masked. To determine how Macrocystis prioritises the use of nitrogen when concentrations are low, the seawater immediately surrounding fronds were enhanced with ecologically relevant pulses of nitrate. The immediate response to fertilisation was not growth, but instead reduced blade erosion and increased pigmentation in canopy tissues. This work suggests that when nitrogen-stressed, Macrocystis first stabilises tissues important to photosynthesis and that growth responses can be delayed for at least one month after initial nitrate pulses. Due to localised increases in pigmentation and soluble nitrate within fronds, this work also highlights potential functional differentiation across tissues.

Extended periods of low nitrogen can be mitigated using reserves. The reserve dynamics within whole Macrocystis fronds are poorly understood but suggested to be small. This work aimed to determine which compounds (pigments, soluble nitrate, amino acids) are important nitrogen reserves, in which tissues these pools are stored (six distinct tissues analysed), and how they explain growth. Ultimately, the data suggest that pigments are not an important nitrogen reserve in Macrocystis because maximum concentrations are low compared to other potential reserves, and because they fluctuate in synchrony with ambient seawater nitrate (i.e. no lag time). Soluble nitrate pools in mature blades, however, accrue to high concentrations when ambient nitrogen is replete (winter/early spring) and then nitrate is slowly disseminated to canopy tissues to fuel spring/early summer growth. When ambient nitrogen is low (summer), there is evidence that amino acids are reabsorbed from canopy blades and translocated to basal tissues, perhaps acting as reserve pools for growth in the autumn.

This thesis addresses aspects of Macrocystis ecophysiology that are important in mitigating nitrogen limitation. The main findings are (1) that mass-transfer rates within kelp beds are highly variable and that increased mass-transfer is critical in ameliorating limitation events, (2) that Macrocystis uses nitrogen towards tissue maintenance before growth when nitrogen-stressed, facilitating continued nutrient uptake and photosynthesis, and (3) that soluble nitrate and amino acids are important nitrogen reserves, but that the former is more important for spring growth and the latter more important for autumn growth.

Caribbean reefs have experienced unprecedented changes in the past four decades. Of great concern is the perceived widespread shift from coral to macroalgal dominance and the question of whether it represents a new, stable equilibrium for coral-reef communities. The primary causes of the shift -- grazing pressure (top-down), nutrient loading (bottom-up) or direct coral mortality (side-in) -- still remain somewhat controversial in the coral reef literature. We have attempted to tease out the relative importance of each of these causes. Four insights emerge from our analysis of an early regional dataset of information on the benthic composition of Caribbean reefs spanning the years 1977–2001. First, although three-quarters of reef sites have experienced coral declines concomitant with macroalgal increases, fewer than 10% of the more than 200 sites studied were dominated by macroalgae in 2001, by even the most conservative definition of dominance. Using relative dominance as the thresh...

The red alga Gracilaria dura is economically important due to its high-quality agarose. Previous studies with wild populations reported the existence of specific differences in functional traits as well as agar characteristics among life cycle stages. In farmed populations, such differences can be exploited for commercial gains. For that, the variation among stages still needs to be well established under farming scenarios. Here, we compared the life cycle stages of G. dura regarding morphological and anatomical structures, growth performance under preliminary field trials, characteristics of agarose of cultivated biomass with biochemical (NMR) and molecular profiling (SCoT). The male gametophyte was found to have a significantly higher growth rate of 6.23 ± 0.59% day −1 than the tetrasporophyte (5.10 ± 0.14% day −1) and cystocarpic female gametophyte (2.67 ± 0.32% day −1). A maximum agarose yield of 28.6 ± 1.53% was obtained from the tetrasporophyte, significantly higher than 27.4 ...

Marine Algae have thousands species, that have various application of today's needy biotechnology material, it has a big potential to solve energy problem. Marine algae have the largest carbon energy content compare to other biomass energy sources. Marine algae can capture large amount of CO 2 , another big potential to solve climate change problems. Various species of marine algae also act as filters to clean the ocean. Macro-algae plantation system has not been tried in many places due to lack of offshore technology usage in aquaculture industry. In order to maintain the competitiveness in macro-algae production in global market, novel cultivation system that will provide large scale production currently need to be developed and the development include conceptual design work already performed on the study is integrated integration into industrial design and testing required for full commercialization. Biological work for ocean water test to determine algae species for Difference Ocean areas is conducted in conjunction with the development of the aquaculture technology platform require for the ocean plantation. This paper describes the biological work on the system.

The present study intends to evaluate the chemical composition, antioxidant activity and GC-MS analysis of marine red seaweed Ahnfeltia plicata. The Alga was collected, shade dried, ground into a fine powder and extracted with eight different solvents to examine their extractive value and phytochemical constituents. The chemical components present in Ahnfeltia plicata were analyzed, and its free radical scavenging activity was determined by the DPPH assay. The seaweed was subjected to GC-MS analysis which revealed the presence of 20 different compounds. From the present research, it is concluded that Ahnfeltia plicata is a rich source of bioactive molecules.

In the present study Hypnea valentiae was collected along the shore of Mandapam and was identified and authenticated. To analyse the methanol extract of marine red macro alga species H. valentiae using Gas chromatography-Mass spectrometry (GC-MS) and in vitro antibacterial activity. Gas chromatography and mass spectrometry analysis of seaweed extract injected with instrument GC-MS-QP 2010 [SHIMADZU] and antibacterial activity of human pathogenic bacteria. The methanol extracts of Hypnea valentiae was identified 27 bioactive compounds which were major compound such Hexadecanoic acid-methylester, 13-Docosenamide, (Z) and Eicosane (RT, 21.07, 34.46, 16.51; 29.10%, 10.27%, 10.24%) Cholest-5-en-3-ol, 24-propylidene-, (3á)-, 9-Octadecenoic acid (Z)-, methyl ester (CAS) (RT39.09, 24.38; 9.00%, 8.07%) Hexadecanoicacid (CAS)-Methyl tetradecanoate (RT 21.89, 17.04; 4.74%, 3.30%). In India, seaweeds have been utilized since the ancient times as source of human food, animal feed, fertilizer, as well as herbicides. In conclusion of the appreciable antimicrobial activity and thus have great potential solvent to extract bioactive compounds from the natural sources for current clinical and pharmaceutical importance.

The red alga Gracilaria dura is economically important due to its high-quality agarose. Previous studies with wild populations reported the existence of specific differences in functional traits as well as agar characteristics among life cycle stages. In farmed populations, such differences can be exploited for commercial gains. For that, the variation among stages still needs to be well established under farming scenarios. Here, we compared the life cycle stages of G. dura regarding morphological and anatomical structures, growth performance under preliminary field trials, characteristics of agarose of cultivated biomass with biochemical (NMR) and molecular profiling (SCoT). The male gametophyte was found to have a significantly higher growth rate of 6.23 ± 0.59% day −1 than the tetrasporophyte (5.10 ± 0.14% day −1) and cystocarpic female gametophyte (2.67 ± 0.32% day −1). A maximum agarose yield of 28.6 ± 1.53% was obtained from the tetrasporophyte, significantly higher than 27.4 ± 0.60% in cystocarpic female gametophyte and 25.2 ± 0.36% in male gametophyte. The gel strength of agarose from male gametophytes was 2384 ± 124.13 g cm −2 , which was significantly higher than the 1900 ± 50 g cm −2 and 2122 ± 124.03 g cm −2 recorded from tetrasporophytes and cystocarpic female gametophytes, respectively. A metabolomic study by NMR spectroscopy showed critical differences in alanine, lactate and isethionic acid among stages. The genetic correlation studied with the SCoT marker showed an average polymorphism of 47.02%. The average heterozygosity and Shannon-Wiener index were 0.63 and 1.06 respectively. This study of characterising and differentiating isomorphic life phases of G. dura by a decisive biomarker could be a valuable reference point to select an appropriate cultivar for commercial farming and breeding programmes.

Caribbean reefs have experienced unprecedented changes in the past four decades. Of great concern is the perceived widespread shift from coral to macroalgal dominance and the question of whether it represents a new, stable equilibrium for coral-reef communities. The primary causes of the shift -- grazing pressure (top-down), nutrient loading (bottom-up) or direct coral mortality (side-in) -- still remain somewhat controversial in the coral reef literature. We have attempted to tease out the relative importance of each of these causes. Four insights emerge from our analysis of an early regional dataset of information on the benthic composition of Caribbean reefs spanning the years 1977–2001. First, although three-quarters of reef sites have experienced coral declines concomitant with macroalgal increases, fewer than 10% of the more than 200 sites studied were dominated by macroalgae in 2001, by even the most conservative definition of dominance. Using relative dominance as the thresh...

Metallic nanoparticles have been traditionally synthesized using wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this research, we present a simple and ecofriendly biosynthesis of Ag nanoparticles using Ulva fasciata crude ethyl acetate extract as reducing and capping agent. The bionanoparticle characterized with UV-vis Spectroscopy, FTIR, XRD, SEM and EDX. Characterization reveals that the nanoparticles are crystalline in nature, spherical in shape and poly-dispersed with size ranging from 28 to 41 nm. The alkyne group (3424.30 cm -1 ) of U. fasciata crude ethyl acetate extract shifted and reduced the AgNO 3 . GC-MS analysis revealed the presence of 1-(Hydroxymethyl)-2, 5, 5, 8A-tetramethyl decahydro-2napthalenol as reducing agent and hexadecanoic acid was found to be a stabilizing agent. Ulva fasciata based bionanoparticles inhibited the growth of Xanthomonas campestris pv. malvacearum (14.00±0.58 mm Zone of inhibition), with a Minimum Inhibitory Concentration of 40.00±5.77µg/mL. The study shows that U. fasciata crude ethyl acetate extract could be used as a reducing agent for simple ecofriendly synthesis of silver nanoparticles. However, more studies are essential before recommending them for disease management.

The largest bay on the Black Sea coast of the Caucasus is Tsemes bay. Novorossiysk city with a population of more than 300 thousand inhabitants is located on the shores of the bay. The most important commercial port of southern Russia is located here. The largest centre of the cement industry operates here on the basis of the developed marl deposit. Cement production is a major source of pollution in the city and the surrounding area. Biogeochemical study of 150 samples of algae revealed the water areas with adverse environmental conditions. Intense accumulation of heavy metals by algae occurs within these areas. Ten years of biogeochemical monitoring showed the general trend of increasing contents of pollutants in algae. Geobotanical study allowed to reveal the most contaminated sites within the waters of Tsemes bay, where the disappearance of most of the species of algae was noted.

Цемесская (Новороссийская) бухта является крупнейшей на Черноморском побережье Кавказа. Расположенный на берегах бухты Новороссийск – город с населением более 300 тыс. жителей. Здесь находится важнейший торговый порт юга России и разрабатывается месторождение мергеля, на основе которого действует крупнейший центр цементной промышленности. Производство цемента является важнейшим источником загрязнения территории города и прилегающей акватории. Биогеохимическое исследование 150 проб водорослей выявило участки акватории с неблагоприятной экологической обстановкой. В их пределах происходит интенсивная аккумуляция тяжелых металлов водорослями. Наиболее загрязненными по результатам геоботанических исследований может быть признана внутренняяя часть бухты. Аквальные ландшафты на этом участке испытывают наибольшее воздействие осажденных из воздуха поллютантов, поступающих с водным стоком. Участки в пределах акватории Цемесской бухты, которые можно характеризовать, как «условно чистые» – западная и восточная оконечность бухты, находящиеся в зонах влияния биогенных ландшафтов суши, однако и на этих участках прослеживается воздействие выбросов цементного завода и иных промышленных предприятий. Наиболее высокие содержания большинства рассмотренных элементов отмечены в пробах, характеризующих центральную часть бухты и акваторию пос. Алексино, наименьшие характерны для проб, отобранных в зонах влияния биогенных ландшафтов лесов. Эти данные биогеохимического мониторинга подтверждают геоботаническую характеристику морских экосистем и выделение наиболее подверженных техногенному воздействию участков. Десятилетний биогеохимический мониторинг (1999–2009 гг.) выявил общую тенденцию к уменьшению средних содержаний большинства рассмотренных элементов в период до 2004 года и возрастание содержаний в 2009 г. При наличии общей тенденции, изменения средних содержаний каждого элемента имеет свои особенности. При этом наиболее низкие средние содержания элементов в пределах акватории города постоянно остаются на уровне, превышающем содержания, характерные для водорослей в зонах влияния биогенных лесных ландшафтов.

Current study was conducted to explore the antiemetic activity of two marine algae, Iyengaria stellata Børgesen (Phaeophycota) and Valoniopsis pachynema Børgesen (Chlorophycota) by chick emesis model. Emesis was induced by copper sulphate (50 mg/kg) and the extracts were tested at the dose of 150 mg/kg orally. Chlorpromazine (150 mg/kg orally) was used as standard antiemetic drug. The results showed that methanol extracts of both the seaweeds have antiemetic activity.

Elimination of heavy metals from contaminated water is a significant issue. Algae can be used as the detoxifying agent of these metals. This study was achieved to assess the efficacy of red marine alga (Jania Rubens) opposed to the initial modifications that may be concerning the toxicity of heavy metal-polluted water on male rats. 45 male Wistar rats were separated into 3 groups (15 rat/ group): Group I (control); Group II (Heavy metal group) and Group III (Treated group). There were significant increases in the levels of SGPT, SGOT, ALP, creatinine, urea, UA, malondialdehyde (MDA), glutathione peroxidase (GPx), protein carbonyl (PC) and significant decrease of body weights& levels of blood hemoglobin, total protein, albumin, catalase, SOD, and GSH in the heavy metal group in comparison with control. Meanwhile, the administration of treated water to rats restores all parameters to normal level in the treated group. Highly significant increase in Metallothionein (MT) levels in hepat...

The red alga Gracilaria dura is economically important due to its high-quality agarose. Previous studies with wild populations reported the existence of specific differences in functional traits as well as agar characteristics among life cycle stages. In farmed populations, such differences can be exploited for commercial gains. For that, the variation among stages still needs to be well established under farming scenarios. Here, we compared the life cycle stages of G. dura regarding morphological and anatomical structures, growth performance under preliminary field trials, characteristics of agarose of cultivated biomass with biochemical (NMR) and molecular profiling (SCoT). The male gametophyte was found to have a significantly higher growth rate of 6.23 ± 0.59% day −1 than the tetrasporophyte (5.10 ± 0.14% day −1) and cystocarpic female gametophyte (2.67 ± 0.32% day −1). A maximum agarose yield of 28.6 ± 1.53% was obtained from the tetrasporophyte, significantly higher than 27.4 ± 0.60% in cystocarpic female gametophyte and 25.2 ± 0.36% in male gametophyte. The gel strength of agarose from male gametophytes was 2384 ± 124.13 g cm −2 , which was significantly higher than the 1900 ± 50 g cm −2 and 2122 ± 124.03 g cm −2 recorded from tetrasporophytes and cystocarpic female gametophytes, respectively. A metabolomic study by NMR spectroscopy showed critical differences in alanine, lactate and isethionic acid among stages. The genetic correlation studied with the SCoT marker showed an average polymorphism of 47.02%. The average heterozygosity and Shannon-Wiener index were 0.63 and 1.06 respectively. This study of characterising and differentiating isomorphic life phases of G. dura by a decisive biomarker could be a valuable reference point to select an appropriate cultivar for commercial farming and breeding programmes.