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Bacteria
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
Some bacteria have the capability of synthesizing all of their cellular carbon compounds from carbon dioxide or carbonate and their other nutritional requirements from nonorganic sources, using energy to do so derived either from (A) the oxidation of one of the following nonorganic chemicals: ferrous iron, ammonium, methane, or inorganic sulfur (these organisms are called chemoautotrophs or autotrophs), or (B) light (these organisms are called photoautotrophs or phototrophs).
Seaweeds
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
L. Stanley Abraham, Vasantharaja Raguraman, R. Thirugnanasambandam, K. M. Smitha, D. Inbakandan, P. Premasudha
Pigments facilitate the phototrophs to trap light as energy, one such abundant pigment is chlorophyll, which has a very close relation with the common green pigment found commonly in all the autotrophs. The next major seaweed pigment is an orange colored pigment viz. carotenoids that play a harmonizing role in photosynthesis by transferring electrons onto chlorophyll. The chlorophyll and carotenoid content in macro algae differs according to the varying levels of UV intensity (Yuan 2007). These pigments exhibit anti-oxidant properties (Aikaterini et al. 2018; Lordan et al. 2011; Yuan 2007).
Dunaliella salina
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Dunaliella salina was first described by Felix Dunal in 1838 and Clara Hamburger in 1905 (Teodoresco 1905; Jaenicke 1998; Oren 2005). They described D. salina as a eukaryotic unicellular microalgae that becomes red-colored when it thrives in the brines of salt lakes and salterns around the halophilic habitats of the French Mediterranean coast (Teodoresco 1905). Presently this genus has been reported in several hypersaline environments in various parts of the world. While Lerche (1937) conducted studies on development and reproduction in Dunaliella, it was Teodoresco (1866–1949) who named D. salina in honor of F. Dunal. Mil’ko (1963) and Massyuk (1966) were the first to propose that D. salina would be an ideal commercial source of natural β-carotene, and they conducted several trials of mass culture of this alga in Ukraine (Massyuk and Abdulla 1969; Borowitzka and Borowitzka 1988). Ben-Amotz et al. (1982) proposed this alga as source of glycerol as well. Actually, Dunaliella salina has been identified in all the hypersaline environments worldwide, where other oxygenic phototrophs fail to grow (Oren 2005). This flagellate alga accumulate the highest amount of β-carotene per cell of any organism, measuring up to 14% on the basis of dry weight (Mil’ko 1963; Aasen et al. 1969; Borowitzka and Borowitzka 1990). It is known that D. salina accumulates around 102 mg of β-carotene per 100 g, while carrots only accumulate 3 mg (USDA National Nutrient Database for Standard Reference Release 18 USA) (Al-Muhteseb and Emeish 2015). β-carotene from D. salina is currently produced on a commercial and pilot scale in several countries, among them Australia, Israel, the United States, India, China, and Spain. In fact, the market for natural β-carotene is increasing worldwide (Figure 14.2).
Short-term succession of marine microbial fouling communities and the identification of primary and secondary colonizers
Published in Biofouling, 2019
Raeid M. M. Abed, Dhikra Al Fahdi, Thirumahal Muthukrishnan
The total biomass, abundance of macrofoulers, chl a and bacterial counts showed a significant gradual increase with time (p < 0.001, ANOVA), reaching their highest values after 28 days deployment. The total biomass increased from 0.17 ± 0.02 mg cm−2 in day 1 to 11.06 ± 3.0 mg cm−2 in day 28 (Figure 1A). The percentage coverage of macrofoulers was <5% until day 7, but then rapidly increased to 21 ± 2.9% of the total surface area of each panel after 28 days (Figure 1B). Chl a concentration, indicative of the abundance of phototrophs, increased from 0.08 ± 0.02 to 0.68 ± 0.2 µg g−1 within the first five days of deployment (Figure 1C). A clear drop in chl a concentrations was observed at day 7, most likely due to increasing grazing activities, after which a sharp increase was observed. Bacterial density showed a steady increase over time, reaching a total of 4.3 × 107 cells g−1 after 28 days (Figure 1D).
Biofilm diversity, structure and matrix seasonality in a full-scale cooling tower
Published in Biofouling, 2018
L. Di Gregorio, R. Congestri, V. Tandoi, T. R. Neu, S. Rossetti, F. Di Pippo
The highest bacterial biodiversity was recorded in winter (Bi-Wi, Figure 1C), when there was a dominance of Alphaproteobacteria (49.6%), with the Bradyrhizobiaceae (20.7%), Sphingomonadaceae (7.3%) and Hyphomicrobiaceae (5.7%) well represented. The Betaproteobacteria were also abundant (9.6%), the most common of which were Comamonadaceae (7.6%). Phototrophs comprised Cyanobacteria (5.5%), primarily the oscillatorialean genera Microcoleus and Leptolyngbya, along with the chroococcalean Pleurocapsa and Chroococcus (Figure 2). Taxonomic assignment of chloroplast OTUs was performed using the BLAST classifier, which revealed the occurrence of the green algae Vischeria sp., Kirchneriella sp. and Scenedesmus sp. Light microscopy and SEM observations revealed the highest species richness of diatoms in winter when they dominated the phototrophic biofilm fraction, with species attributable to the genera Navicula, Nitzschia and Surirella predominant. Amphora sp., Cymbella sp. and Pinnularia sp. were also present (Figure 3A–C).
Multistep approach to control microbial fouling of historic building materials by aerial phototrophs
Published in Biofouling, 2019
Paulina Nowicka-Krawczyk, Joanna Żelazna-Wieczorek, Anna Koziróg, Anna Otlewska, Katarzyna Rajkowska, Małgorzata Piotrowska, Beata Gutarowska, Bogumił Brycki
It is impossible to halt the gradual degradation and deterioration of man-made objects. Their surfaces degrade with the passing of time and under the influence of physical, chemical and biological factors, no matter what material they are made of. Microorganisms promote the deterioration of such materials as a result of their role in the environment (Junier and Joseph 2017). Some are decomposers of organic matter (Güsevell and Gessner 2009), while others are pioneer organisms producing organic matter from simple mineral components by photosynthesis (Graham et al. 2009). The latter are easily spread by wind throughout the terrestrial environments of all climatic zones and colonize substrata, creating visible ‘green’ coatings (Barberousse et al. 2007; Genitsaris et al. 2011). However, from an environmental perspective, the question arises whether colonization should be considered a problem. The answer depends on our social and cultural needs. In terms of history, evidence of the changes taking place over the centuries to buildings, memorials and monuments is extremely important. Phototrophic coatings not only decrease the aesthetic value, but also in many cases accelerate the rate of deterioration. Cyanobacteria and algae are able to grow into the substratum, causing mechanical deterioration, whilst changes in the volume of cells during water accumulation or secretion also cause microdamage to the substratum (Samad and Adhikary 2008; Grbić et al. 2010; Rajkowska et al. 2014). Some authors have questioned the direct contribution of phototrophs to the biodeterioration of historic objects, claiming that they are not the primary damaging factors (Ortega-Calvo et al. 1995; Gullota et al. 2018). However, they produce and secrete organic and inorganic compounds, which have been found to affect substrata and change their chemical composition (Cutler et al. 2013). Gaylarde and Morton (1999) highlight the deterioration abilities of cyanobacteria in tropical climate zones. Moreover, aerial phototrophs, being pioneers and primary producers, provide significant organic matter input, facilitating bacterial and fungal colonization, and thus allowing successive deterioration by heterotrophic microorganisms (Ortega-Calvo et al. 1995; May et al. 2011).