scholarly journals Macroalgae

Encyclopedia ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 177-188
Author(s):  
Leonel Pereira
Keyword(s):  
Carbon Dioxide ◽  
Chlorophyll A ◽  
Red Algae ◽  
Great Variability ◽  
Marine Macroalgae ◽  
Brown Macroalgae ◽  
Green Macroalgae ◽  
Red Macroalgae ◽  
Photosynthetic Organisms ◽  
Green Pigments

What are algae? Algae are organisms that perform photosynthesis; that is, they absorb carbon dioxide and release oxygen (therefore they have chlorophyll, a group of green pigments used by photosynthetic organisms that convert sunlight into energy via photosynthesis) and live in water or in humid places. Algae have great variability and are divided into microalgae, small in size and only visible through a microscope, and macroalgae, which are larger in size, up to more than 50 m (the maximum recorded was 65 m), and have a greater diversity in the oceans. Thus, the term “algae” is commonly used to refer to “marine macroalgae or seaweeds”. It is estimated that 1800 different brown macroalgae, 6200 red macroalgae, and 1800 green macroalgae are found in the marine environment. Although the red algae are more diverse, the brown ones are the largest.

Mechanistic interpretation of carbon isotope discrimination by marine macroalgae and seagrasses

2002 ◽  
Vol 29 (3) ◽  
pp. 355 ◽  
Author(s):  
John A. Raven ◽  
Andrew M. Johnston ◽  
Janet E. Kübler ◽  
Rebecca Korb ◽  
Shona G. McInroy ◽  
...  
Keyword(s):  
Red Algae ◽  
Carbon Isotope Discrimination ◽  
Red Alga ◽  
Marine Macroalgae ◽  
Brown Macroalgae ◽  
Green Macroalgae ◽  
Δ13c Values ◽  
Δ13c Value ◽  
Co2 Concentrating Mechanisms ◽  
Plocamium Cartilagineum

The literature, and previously unpublished data from the authors’ laboratories, shows that the δ13C of organic matter in marine macroalgae and seagrasses collected from the natural environment ranges from –3 to –35‰. While some marine macroalgae have δ13C values ranging over more than 10‰ within the thallus of an individual (some brown macroalgae), in other cases the range within a species collected over a very wide geographical range is only 5‰ (e.g. the red alga Plocamium cartilagineum which has values between –30 and –35‰). The organisms with very negative δ13C (lower than –30‰) are mainly subtidal red algae, with some intertidal red algae and a few green algae; those with very positive δ13C values (higher than –10‰) are mainly green macroalgae and seagrasses, with some red and brown macroalgae. The δ13C value correlates primarily with taxonomy and secondarily with ecology. None of the organisms with δ13C values lower than –30‰ have pyrenoids. Previous work showed a good correlation between δ13C values lower than –30‰ and the lack of CO2 concentrating mechanisms for several species of marine red algae. The extent to which the low δ13C values are confined to organisms with diffusive CO2 entry is discussed. Diffusive CO2 entry could also occur in organisms with higher δ13C values if diffusive conductance was relatively low. The photosynthesis of organisms with δ13C values more positive than –10‰ (i.e. more positive than the δ13C of CO2 in seawater) must involve HCO3- use.

scholarly journals Marine benthic algal flora of Ascension Island, South Atlantic

2014 ◽  
Vol 97 (4) ◽  
pp. 681-688 ◽  
Author(s):  
Konstantinos Tsiamis ◽  
Akira F. Peters ◽  
Dawn M. Shewring ◽  
Aldo O. Asensi ◽  
Pieter Van West ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Red Algae ◽  
Brown Algae ◽  
South Atlantic ◽  
Marine Macroalgae ◽  
Algal Flora ◽  
Red Macroalgae ◽  
Ascension Island ◽  
Infraspecific Taxa ◽  
First Time

This paper provides a comprehensive checklist of the marine benthic macroalgal flora of Ascension Island (tropical South Atlantic Ocean), based on both new collections and previous literature. 82 marine macroalgae were identified from our work, including 18 green algae (Ulvophyceae), 15 brown algae (Phaeophyceae) and 49 red algae (Rhodophyta). Among our collections, 38 species and infraspecific taxa are reported for the first time from Ascension Island, including seven green, three brown and 28 red macroalgae, raising the total number of seaweeds recorded in Ascension so far to 112 taxa in species and infraspecific level. No seagrasses have been recorded at Ascension Island.

Occurrence and chemical form of arsenic in marine macroalgae from the east coast of Australia

2002 ◽  
Vol 53 (6) ◽  
pp. 971 ◽  
Author(s):  
R. Tukai ◽  
W. A. Maher ◽  
I. J. McNaught ◽  
M. J. Ellwood ◽  
M. Coleman
Keyword(s):  
General Pattern ◽  
Arsenic Concentration ◽  
Inorganic Arsenic ◽  
Marine Macroalgae ◽  
Dimethylarsinic Acid ◽  
Arsenic Compounds ◽  
Brown Macroalgae ◽  
Macroalgal Species ◽  
Red Macroalgae ◽  
High Concentrations

Arsenic concentrations were measured in thirteen macroalgal species from Sydney, Australia. Brown macroalgae contained, on average, more arsenic (range, mean ± s.e.: 5–173 μg g–1, 39 ± 4 μg g–1) than either green (0.12–30.2 μg g–1, 10.7 ± 0.7 μg g–1) or red macroalgae (0.11–16.9 μg g–1, 4.3 ± 0.3 μg g–1). Despite the overlap in arsenic concentrations between different macroalgal species, inter-species arsenic variation was apparent with arsenic concentrations following the order brown > green > red macroalgal species. It was concluded that the main contribution to the variation in arsenic concentration was from natural variability expected to occur between individuals of any species as a result of physiological differences.Most of the arsenic compounds in macroalgae (70–108%) could be extracted using methanol/water mixtures, with 38–95% of the arsenic compounds present in characterizable forms. All macroalgal species contained arsenoribosides (9–99%). The distribution of arsenoribosides followed a general pattern; glycerol-arsenoriboside and phosphate-arsenoriboside were common to all macroalgal species. Sulfonate-arsenoriboside and sulfate-arsenoriboside were found in brown macroalgal species and one red macroalgal species. Six macroalgal species contained high concentrations of inorganic arsenic (14.2–62.9%) and four species contained high concentrations of dimethylarsinic acid (13.3–41.1%). The variation in the distribution of arsenic compounds in marine macroalgal species appears to be related to taxonomic differences in storage and structural polysaccharides.

scholarly journals Distribution and Diversity of Benthic Marine Macroalgae in Islands around Qatar

2020 ◽  
Author(s):  
Aisha Ahmed Al-AShwal ◽  
Noora Al-Naimi ◽  
Jassim Al-Khayat ◽  
Bruno Giraldes ◽  
Najat Al-Omari ◽  
...  
Keyword(s):  
Species Richness ◽  
Red Algae ◽  
Marine Ecosystem ◽  
Arabian Gulf ◽  
Marine Macroalgae ◽  
Harsh Environment ◽  
Brown Macroalgae ◽  
Invertebrate Animals ◽  
Study Sites ◽  
Marine Zone

Extending into the Arabian Gulf, Qatar is surrounded by a number of islands mostly scattered by the eastern coastline. With the unique physical characteristics of the Gulf, which is a highly saline sea with high seawater temperatures, there is an urge need to investigate the macroalgae living in such harsh environment. Macroalgae plays an important role in the food web as they are primary producers and providers of food for other organisms. They also provide shelter and habitat in the marine ecosystem for herbivorous fish and other invertebrate animals. Additionally, macroalgae plays an outstanding role in reducing CO2 from the atmosphere and increasing the level of dissolved oxygen in their immediate environment. However, there are few studies on marine macroalgae in Qatar and no previous studies found related to macroalgae from the islands around Qatar. The present work contributes to the macroalgae research by providing the first survey of distribution and diversity of benthic marine macroalgae in islands around Qatar. The marine benthic green, red and brown macroalgae of intertidal and subtidal in marine zone areas around Qatar were collected during Qatar’s Islands project, which started 2018. The collected macroalgae are documented and a total of 67 species of macroalgae are recorded for all islands around Qatar, 24 Chlorophyta (Green algae), 25 Rhodophyta (Red algae) and 18 species Phaeophyta (Brown algae). The Red algae are dominant taxon in term of species richness, accounting for an average of 37% of the species at all study sites. The islands which had more species are Al-Beshaireya 58 Species, Al-Aaliya 53 Species, Sheraouh 48 Species, Janan 43 Species and Bu Felaita 37 Species. Our results show that islands located at eastern and southeastern coast of Qatar have more diversity of algae species than those located at the western and northwestern coast.

scholarly journals Molecular Detection of Epiphytic Acaryochloris spp. on Marine Macroalgae

2006 ◽  
Vol 72 (12) ◽  
pp. 7912-7915 ◽  
Author(s):  
Satoshi Ohkubo ◽  
Hideaki Miyashita ◽  
Akio Murakami ◽  
Haruko Takeyama ◽  
Tohru Tsuchiya ◽  
...  
Keyword(s):  
Gel Electrophoresis ◽  
Molecular Detection ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Marine Macroalgae ◽  
Rrna Gene ◽  
Molecular Method ◽  
Brown Macroalgae ◽  
Red Macroalgae ◽  
Gradient Gel Electrophoresis ◽  
Epiphyte Community

ABSTRACT A molecular method for detecting the epiphyte community on marine macroalgae was developed by using PCR-denaturing gradient gel electrophoresis. Selective amplification of 16S rRNA gene fragments from either cyanobacteria or algal plastids improved the detection of minor epiphytes. Two phylotypes of Acaryochloris, a chlorophyll d-containing cyanobacterium, were found not only on red macroalgae but also on green and brown macroalgae.

Etude sur la teneur en pigment de frênes qui croissent dans des conditions différentes

1973 ◽  
Vol 37 ◽  
Author(s):  
N. Lust
Keyword(s):  
Chlorophyll A ◽  
Strong Influence ◽  
The Other ◽  
Pigment Content ◽  
Chlorophyll B ◽  
Light Quantity ◽  
Yellow Pigments ◽  
The One ◽  
Green Pigments

Pigment content of ashes grown up under different circumstances - The pigment content (chlorophyll a, chlorophyll b,  xanthophyll and carotene) has been researched with ashes grown up under  different light circumstances and varying in age and height.     The results prove that the general laws concerning the influence of light  on the pigment content, don’t always work.     The phenomen is very complex. The light quantity is very important in some  cases, but insignificant in others. It seems origin and height of plants have  a strong influence. The results prove also the influence of the environment  is much higher on small plants as on big ones.     The research indicates finally the correlation between the green pigments,  the yellow pigments, and between the green pigments on the one side and the  yellow ones on the other side.

scholarly journals HUBUNGAN IKAN PELAGIS DENGAN KONSENTRASI KLOROFIL-A DI LAUT JAWA

2015 ◽  
Vol 6 (1) ◽  
pp. 21
Author(s):  
Kamaluddin Kasim ◽  
Setiya Triharyuni ◽  
Arief Wujdi
Keyword(s):  
Chlorophyll A ◽  
Aquatic Organism ◽  
Predator Species ◽  
Pelagic Species ◽  
Photosynthetic Organisms ◽  
Bivariate Correlation ◽  
Java Sea ◽  
Rastrelliger Kanagurta ◽  
Euthynnus Affinis ◽  
As Relationship

Klorofil-a banyak ditemukan pada fitoplankton dan menjadi indikator kesuburan perairan. Keberadaan fitoplankton ditandai dengan kandungan klorofil-a yang tinggi dan diikuti oleh keberadaan zooplankton yang akhirnya mempengaruhi keberadaan organisme perairan lainnya seperti ikan pelagis kecil maupun ikan pelagis besar sebagai suatu rantai makanan. Interaksi antara konsentrasi klorofil-a terhadap keberadaan dan konsentrasi ikan pelagis di Laut Jawa belum banyak diketahui. Penelitian ini dimaksudkan untuk mengetahui hubungan interaksi antara klorofil-a terhadap konsentrasi ikan pelagis. Penelitian dilakukan dengan mengumpulkan data runtun waktu hasil tangkapan beberapa jenis pelagis besar dan kecil yang didaratkan di PPI Pekalongan tahun 2007-2011 serta data runtun waktu konsentrasi klorofil-a dari perairan utara Jawa yang diperoleh dari informasi sekunder.Metode analisis korelasi linear sederhana (bivariate correlation) digunakan untukmengetahui ada atau tidaknya pengaruh antar variabel klorofil-a dan konsentrasi ikan pelagis. Hasil penelitian menunjukkan bahwa ikan layang (Decapterus russelli) paling nyata mendapat pengaruh dari konsentrasi klorofil-a (P<0,05) dan berkorelasi positif terhadap konsentrasi klorofil-a dengan nilai koefisien korelasi ( r ) sebesar 0,56, sedangkan ikan pelagis lainnya berkorelasi negatif. Ikan tongkol (Euthynnus affinis) posisinya menempati rantai makanan paling tinggi sebagai pemangsa, mempunyai korelasi positif (r = 0,5) terhadap Rastrelliger kanagurta dan r = 0,56 terhadap Amblygaster sirm.Chlorophyll-a is a light-absorbing pigment that can be found in photosynthetic organisms such as algae and phytoplankton. The evidence of phytoplankton that indicated by high contents of chlorophyll-a may followed the evidence of zooplankton and other micro aquatic organism as a food chain component. An overview of interrelationships between chlorophyll-a and pelagic fishes in the waters around Java Sea have not much investigated. The research was attempted to study the interaction between chlorophyll-a abundance and the abundance of small and large pelagic as well as relationship among small and large pelagic as prey-predators component. Research conducted by collecting time series catch data of small and large pelagic species landed at PPI Pekalongan during the period of 2006-2012, as well as the data of chlorophyll-a abundance through previous research studies. The results showed that layang (Decapterus russelli) was the most significant species that positively correlated to abundance of chlorophyll-a (P < 0.05) with value of r = 0.6. while others pelagic species have negative correlation. As a predator species, tongkol (Euthynnus affinis) was positively correlated ( r = 0.5) to the abundance of banyar (Rastrelliger kanagurta) as well as juwi (Amblygaster sirm) with r value 0.56.

Structural effects on epimerization of bacteriochlorophyll a and chlorophyll a revealed using 3-acetyl chlorophyll a

2020 ◽  
Vol 24 (04) ◽  
pp. 499-504 ◽  
Author(s):  
Yoshitaka Saga ◽  
Shiori Nakagawa
Keyword(s):  
Physicochemical Properties ◽  
Chlorophyll A ◽  
Photosynthetic Reaction Center ◽  
Molecular Structures ◽  
Structural Factors ◽  
Structural Effects ◽  
Photosynthetic Organisms ◽  
Acetyl Group ◽  
Kinetics Of

Chlorophyll (Chl) and bacteriochlorophyll (BChl) pigments, which are crucial cyclic tetrapyrroles in photosynthesis, generally have a chiral center in their exo-cyclic five-membered E-ring. Although [Formula: see text]-epimers (primed-type) of (B)Chl pigments are rarely present in photosynthetic organisms, they play key roles in photosynthetic reaction center complexes. The epimerization mechanism of (B)Chl pigments in vivo has not been unraveled. The structural effects on the physicochemical properties of (B)Chl epimerization reactions provide useful information to tackle this question. We analyzed epimerization of three pigments, BChl [Formula: see text], Chl [Formula: see text], and 3-acetyl Chl [Formula: see text], to elucidate the structural factors that are responsible for epimerization reactions. We compared the epimerization kinetics of the three pigments and concluded that the bacteriochlorin skeleton (7,8,17,18-tetrahydroporphyrin) significantly retarded the epimerization kinetics. Thus, BChl [Formula: see text] exhibited slower epimerization kinetics than Chl [Formula: see text] in spite of the presence of the electron-withdrawing 3-acetyl group that accelerates epimerization. In contrast to the large structural effects of (B)Chl molecules on epimerization kinetics, the thermodynamic properties at equilibrium in the epimerization of the three pigments were barely influenced by their molecular structures. This study also demonstrates that a semi-synthetic pigment, 3-acetyl Chl [Formula: see text], is appropriate for comparative analyses of the structural effects of BChl [Formula: see text] and Chl [Formula: see text] on their physicochemical properties.

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