5. Microbial engines of the coral reef

2021 ◽  
pp. 58-67
Author(s):  
Charles Sheppard
Keyword(s):  
Organic Matter ◽  
Coral Reef ◽  
Organic Compounds ◽  
Green Algae ◽  
Major Part ◽  
Food Chains ◽  
Primary Producers ◽  
Blue Green Algae ◽  
Form Part ◽  
Species Groups

The symbiosis between corals and the dinoflagellates—zooxanthellae—is the key to a tight recycling of nutrients on reefs that generally thrive best in nutrient poor parts of the oceans. But several other mechanisms and species groups aid transmission of organic matter and energy along the numerous food chains of a reef. Viruses, bacteria, and archaea are key to the recycling of carbon and organic compounds, making the ‘microbial loop’, one key but invisible aspect to how the reef functions. Cyanobacteria, formerly blue-green algae, are a major part of the micro-benthos too, and are important primary producers. Protists are also hugely abundant—larger, single-celled organisms which are eukaryotes with cells with nuclei, and this group has species that exist in planktonic and benthic forms. Foraminifera are important protists, being abundant and having calcareous tests, so that they are significant sand producers in some areas. Finally, zooplankton provide food for numerous reef species, and indeed larvae from all species form part of the plankton temporarily too.

Volatile Compounds of the Cyanophyceae – A Review

1983 ◽  
Vol 15 (6-7) ◽  
pp. 181-190 ◽  
Author(s):  
George P Slater ◽  
Vivian C Blok
Keyword(s):  
Fatty Acids ◽  
Volatile Compounds ◽  
Organic Compounds ◽  
Green Algae ◽  
Aquatic Organisms ◽  
Blue Green Algae ◽  
Green Algal

A relationship between blue-green algae and off-flavours in water was reported as early as 1883. Continuing research has shown that two metabolites, geosmin and methylisoborneol are major contributors to unpalatable flavours in water and aquatic organisms. Many instances of the co-occurrence of these two compounds and dense blooms of blue-green algae have been recorded. Cultures of Anabaena, Lyngbya, Osciiiatoria, and Sympioca species have been shown to produce geosmin or methylisoborneol while blooms of Aphanizomenon, Anabaena, Microcystis, Oscillatoria, and Gomphosphaeria have been found in water containing geosmin or the odour of this compound. Actinomycetes have also been shown to produce these two compounds. In addition to geosmin and methylisoborneol, there is evidence that several other blue-green algal metabolites contribute to aquatic taste and odour problems. Among them is β-cyclocitral which has a distinctive tobacco flavour. Blue-green algae produce a variety of organic compounds including hydrocarbons, fatty acids, aromatics, ketones, terpenoids, amines and Sulfides which could contribute to the over-all flavour of water and aquatic organisms.

On the Ecology of Larvae of Anopheles culicifacies Giles, in Borrow-pits

1942 ◽  
Vol 32 (4) ◽  
pp. 341-361 ◽  
Author(s):  
Paul F. Russell ◽  
T. Ramachandra Rao
Keyword(s):  
Organic Matter ◽  
Green Algae ◽  
Larval Density ◽  
Negative Association ◽  
Irrigation Season ◽  
Anopheles Culicifacies ◽  
Internal Factors ◽  
Blue Green Algae ◽  
Meteorological Influences ◽  
The Individual

(1) In seepage-filled borrow-pits in South India it was observed that there was a progressive decline in the density of larvae of Anopheles culicifacies, Giles, as the pits became older. The largest numbers of larvae were tound soon after water entered the newly-dug pits.(2) There was less ovipositing by culicifacies in older pits than in new ones dug late in the irrigation season. Newer pits seemed definitely more attractive in this species than older ones. These newer pits sheltered more culicifacies larvae late in the season than the older pits.(3) The decline of culicifacies larva density in a borrow-pit seemed to be due mainly to factors internal to the pits. There was no evidence of the influence of external factors, except from October to January, when perhaps meteorological influences supplemented the internal factors. The attractiveness of new borrow-pits to culicifacies appeared to be due mainly to internal factors.(4) Certain simple factors studied did not seem to have any significance in relation to culicifacies density in the pits. Rainfall, predators, macroscopic vegetation, pH, CO2, dissolved oxygen, bicarbonate alkalinity, ratio of free to bound and half bound CO2, hardness, chlorine, ammoniacal nitrogen, nitrates, nitrites, sulfates and iron, appeared to have no significance in this regard. Albuminoid nitrogen and oxygen absorbed perhaps had some significance, which was not clear.(5) Among planktonic organisms, the individual groups of organisms, such as green algae, diatoms, rotifers, and copepods, definitely showed no relation to culicifacies breeding. Protozoa as a group appeared to be negatively associated to a slight degree. Blue-green algae also seemed to have a negative association.(6) Amorphous organic matter and total plankton, however, showed statistically significant negative association with larval density of culicifacies The decline in culicifacies larvae was clearly associated with increase in total plankton and amorphous matter. The attractiveness of new borrow-pits also seemed to be related to their low total plankton content.(7) The exact manner in which the total organic matter acted as an inhibitory factor against culicifacies breeding was not determined.

Heterotrophic potential of Phormidium and other blue-green algae

1974 ◽  
Vol 52 (11) ◽  
pp. 2369-2374 ◽  
Author(s):  
Daniel H. Pope
Keyword(s):  
Organic Compounds ◽  
Green Algae ◽  
Phaeodactylum Tricornutum ◽  
Metabolic Inhibitors ◽  
Blue Green Algae ◽  
Free Sample ◽  
Uptake Rates ◽  
Axenic Cultures ◽  
Marine Algal ◽  
Olive Green

Several algal types were tested for the ability to assimilate a variety of organic compounds including glucose, sucrose, glycerol, acetate, and a variety of amino acids. Axenic cultures of Phaeodactylum tricornutum, Cricosphaera sp., and Dunaliella tertiolecta failed to take up any of the compounds tested. Axenic cultures of the filamentous blue-green algae Phormidium sp. and Lyngbya sp. took up all of the test substrates, as did the "olive-green cells" (a non-bacteria-free sample of marine algal cells described as olive-green cells by other workers). The results of experiments to determine uptake rates over the range 10−7 to 10−3 molar substrate, rates of uptake at 18, 24, and 32C, and rates of uptake in the presence of the metabolic inhibitors dinitrophenol (DNP) and carbanyl cyanide m-chlorophenylhydrazone (CCCP) indicated that uptake of the organic compounds tested by the filamentous blue-green algae tested is not by an active transport mechanism.

scholarly journals Industrial Applications of Cyanobacteria

2021 ◽  
Author(s):  
Ayesha Algade Amadu ◽  
Kweku Amoako Atta deGraft-Johnson ◽  
Gabriel Komla Ameka
Keyword(s):  
Secondary Metabolites ◽  
Organic Compounds ◽  
Green Algae ◽  
Bioactive Compounds ◽  
Metabolic Pathways ◽  
Antifungal Agents ◽  
Industrial Applications ◽  
Blue Green Algae ◽  
Oil Components ◽  
Complex Organic

Cyanobacteria also known as blue-green algae are oxygenic photoautotrophs, which evolved ca. 3.5 billion years ago. Because cyanobacteria are rich sources of bioactive compounds, they have diverse industrial applications such as algaecides, antibacterial, antiviral and antifungal agents, hence, their wide use in the agricultural and health sectors. Cyanobacterial secondary metabolites are also important sources of enzymes, toxins, vitamins, and other pharmaceuticals. Polyhydroxy- alkanoates (PHA) which accumulate intracellularly in some cyanobacteria species can be used in the production of bioplastics that have properties comparable to polypropylene and polyethylene. Some cyanobacteria are also employed in bioremediation as they are capable of oxidizing oil components and other complex organic compounds. There are many more possible industrial applications of cyanobacteria such as biofuel, biofertilizer, food, nutraceuticals, and pharmaceuticals. Additionally, the metabolic pathways that lead to the production of important cyanobacterial bioactive compounds are outlined in the chapter along with commercial products currently available on the market.

scholarly journals The Photoassimilation of Organic Compounds by Autotrophic Blue-green Algae

1967 ◽  
Vol 49 (3) ◽  
pp. 351-370 ◽  
Author(s):  
D. S. Hoare ◽  
S. L. Hoare ◽  
R. B. Moore
Keyword(s):  
Organic Compounds ◽  
Green Algae ◽  
Blue Green Algae

Matière organique dissoute dans l'estuaire maritime du St-Laurent — comparaison et choix des méthodes

1974 ◽  
Vol 31 (2) ◽  
pp. 133-139 ◽  
Author(s):  
D. Cauchois ◽  
M. Khalil
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Water Column ◽  
Organic Compounds ◽  
Major Part ◽  
Sea Water ◽  
Liquid Extraction ◽  
Total Organic Matter ◽  
Liquid Liquid Extraction

To study quantitatively and qualitatively the dissolved organic matter in the St. Lawrence maritime estuary, a comparison between the different extracting methods has been undertaken. We propose two of them; one based on liquid–liquid extraction, the second by adsorption on a resin (Amberlite XAD-2). The methods used remove different spectrums of organic compounds from sea water. Hydrocarbons were found to constitute the major part of the extracts varying between 3 and 5 mg/liter. None of the methods used extracts more than 20% of the total organic matter present. The concentration of the organic chloro-compounds in the water column is in the order of 80 ppb.

Effects of Potassium Permanganate Preoxidation Followed with Coagulation on the Fluorescence Spectrum of Algae

2011 ◽  
Vol 71-78 ◽  
pp. 2920-2924 ◽  
Author(s):  
Peng Chao Xie ◽  
Jing Yun Fang ◽  
Jun Ma
Keyword(s):  
Organic Matter ◽  
Fluorescence Spectrum ◽  
Potassium Permanganate ◽  
Green Algae ◽  
Fluorescence Intensity ◽  
Fluorescence Spectra ◽  
Organic Matters ◽  
Blue Green Algae ◽  
Kind Of Blue

This study was performed to illustrate the effects of preoxidation by potassium permanganate on the fluorescence spectrum of Microcysis aeruginosa, a kind of blue-green algae. The results showed there were four dominate excitation/emission (Ex/Em) wavelength pairs, 230/334, 280/312, 280/334 and 620/642 nm/nm in the fluorescence spectra of algae and their derived organic matters (AOM). Coagulation resulted in desorption of the organic matter adsorbed in algae cells and produced two new fluorophores centered at 275/460 and 400/460 nm/nm. Potassium permanganate preoxidation could reduce the fluorescence intensity of algae and dissolved algal organic matters effectively and the descent rate increased with increasing potassium permanganate dosage.

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