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Hepatoprotective Marine Phytochemicals
Published in Se-Kwon Kim, Marine Biochemistry, 2023
BR Annapoorna, S Vasudevan, K Sindhu, V Vani, V Nivya, VP Venkateish, P Madan Kumar
Phlorotannins (1,3,5-trihydroxy benzene) are polymers of phloroglucinol exclusively found in brown algae and biosynthesized through the acetate–malonate pathway. Different types of phlorotannins have been identified from different marine species, a few of which include Phlorofucofuroeckol A, dieckol, dioxinodehydroeckol, eckstolonol, triphlorethol-A, fucosterol, phloroglucinol, eckol, phlorofucofuroeckol-A, 2-phloroeckol, 7-phloroeckol (Kim et al. 2009). Among marine brown algae, Ecklonia cava, Ecklonia stolonifera, Ecklonia kurome, Eisenia bicyclis, Ishige okamurae, Sargassum thunbergii, Hizikia fusiformis, Undaria pinnatifida, and Laminaria japonica have been reported for phlorotannins with beneficial health biological activities (Li et al. 2011). A few of the carotenoids isolated from marine sources such as algae, fungi, and bacteria include astaxanthin (Hematococcus pluvialis), fucoxanthin (Sargassum siliquastrum, Hijikia fusiformis, Undaria pinnatifida, Laminaria japonica), tedaniaxanthin, lutein (Dunaliella salina), siphonaxanthin, lycopene (haloarchaea), antheraxanthin, zeaxanthin (Halophila stipulacea), violaxanthin, neoxanthin, peridinin (Heterocapsa triquetra), β-cryptoxanthin β-carotene (Dunaliella salina), ketocarotenoids, canthaxanthin (Thraustochytrium strains ONC-T18 and CHN-1), echinenone, diadinoxanthin, dinoxanthin, and alloxanthin (Galasso et al. 2017).
Introduction to cyanobacteria
Published in Ingrid Chorus, Martin Welker, Toxic Cyanobacteria in Water, 2021
Leticia Vidal, Andreas Ballot, Sandra M. F. O. Azevedo, Judit Padisák, Martin Welker
Cyanobacterial water blooms can have a wide variety of colours beyond the typical green or blue-green colour due to varying ratios of chlorophylls, phycocyanin, phycoerythrin and carotenoids. The latter are orange or red in colour, and they can be used to quantify phytoplankton groups, for example, by HPLC (high performance liquid chromatography) analysis of echinenone or canthaxanthin, which are specific for cyanobacteria (Frigaard et al., 1996; Takaichi, 2011). Surface blooms can appear orange, brownish, purple, and light green, among other colours, and have been occasionally reported as suspected “contamination with paint” due to their unexpected colour.
Single-Cell Protein Production
Published in Debabrata Das, Soumya Pandit, Industrial Biotechnology, 2021
An ideal cell of Spirulina has following components: Vitamins: Vitamin B1, Vitamin B2, Vitamin B3, Vitamin B6, Vitamin B9, Vitamin B12, Vitamin C, Vitamin E and Vitamin D.Protein: 55%–70% protein; amount calculated by dry weight. Contains all essential amino acids.Minerals: Contains calcium, potassium, copper, chromium, iron, manganese, magnesium, selenium, phosphorus, zinc and sodium.Fatty acids: Contains high amount of polyunsaturated fatty acids or PUFA, γ-linolenic acid (ALA), linoleic acid (LA), eicosapentaenoic acid (EPA), steariodonic acid (SDA), arachidonic acid (AA) and docosahexaenoic acid (DHA).Photosynthetic pigments: Contains chlorophyll a, beta-carotene, xanthophyll, echinenone, zeaxanthin, myxoxanthophyll, diatoxanthin, canthaxanthin, beta-cryptoxanthin, oscillaxanthin, 3-hydroxyechinenone, allophycocyanin and c-phycocyanin. This is a brief composition of Spirulina cells; experiments have been conducted to get a more detailed composition of these cells. Depending on the origination of the species the composition changes (Saranraj and Sivasakthi, 2014). Table 16.2 shows the approximate composition of Spirulina cells deriving from France, India, Thailand, Malaysia and Bangladesh.
Marked blue discoloration of late winter ice and water due to autumn blooms of cyanobacteria
Published in Lake and Reservoir Management, 2022
Heather A. Haig, Amir M. Chegoonian, John-Mark Davies, Deirdre Bateson, Peter R. Leavitt
Chl-a samples were analyzed using standard trichromatic methods (Jeffrey and Humphrey 1975), while high performance liquid chromatography (HPLC) was used to quantify changes in phytoplankton community composition (Leavitt and Hodgson 2001, Donald et al. 2013). Briefly, chlorophyll, carotenoid, and derivative pigments were extracted from POM on GF/C filters, dried under inert N2 gas, and redissolved into an injection solution before introduction into a fully calibrated Agilent Model 1100 HPLC fitted with photodiode array and fluorescence detectors. Lipid-soluble biomarker pigments (nmol pigment/L) were quantified for total phytoplankton abundance (Chl-a, pheophytin-a, β-carotene), siliceous algae (fucoxanthin), main diatoms (diatoxanthin, diadinoxanthin), cryptophytes (alloxanthin), dinoflagellates (peridinin), chlorophytes and cyanobacteria (lutein-zeaxanthin), chlorophytes alone (Chl-b), total cyanobacteria (echinenone), colonial cyanobacteria (myxoxanthophyll), Nostocales cyanobacteria (canthaxanthin), and potentially N2-fixing cyanobacteria (aphanizophyll) following Leavitt and Hodgson (2001). Ratios of concentrations of undegraded Chl-a to pheophytin-a (Chl-a:Pheo-a) were used to estimate phytoplankton vitality, as the latter compound is a Chl-a degradation product that is normally rare in living cells (Leavitt and Hodgson 2001).
Contrasting histories of microcystin-producing cyanobacteria in two temperate lakes as inferred from quantitative sediment DNA analyses
Published in Lake and Reservoir Management, 2019
Shinjini Pilon, Arthur Zastepa, Zofia E. Taranu, Irene Gregory-Eaves, Marianne Racine, Jules M. Blais, Alexandre J. Poulain, Frances R. Pick
There are few sufficiently long-term monitoring programs of phytoplankton, and therefore it is difficult to determine whether blooms are indeed increasing and/or becoming more toxic. In contrast, sediment cores can be used to track algal communities and reconstruct environmental history using various proxies over much longer periods (Smol 2008). The subfossil remains of some species are well suited to identification using light microscopy, such as with the silica frustules of diatoms and scales of chrysophytes (Smol 2008). Some cyanobacterial taxa develop resting stages (akinetes) and can therefore be detected in a similar way (van Geel et al. 1994; Räsänen et al. 2006; Legrand et al. 2017). Cyanobacteria also produce characteristic pigments that can be extracted from sediments: Carotenoid pigments (echinenone and zeaxanthin) representative of cyanobacteria have been used to pinpoint the onset of eutrophication in temperate lakes (e.g., Leavitt and Hodgson 2002). Based on pigment analyses, the sediment record over the last 200 yr, particularly of temperate lakes, points to a global increase in cyanobacteria mainly post ∼1945 CE (Taranu et al. 2015), but the history and dynamics of toxic blooms have not been well resolved to date, partly for lack of suitable proxies.
Shallow water phytoplankton responses to nitrate and salinity enrichment may be modified by benthic processes
Published in Inland Waters, 2020
Suzanne McGowan, Peter R. Leavitt, Tom Barker, Brian Moss
Time series plots demonstrated the seasonal nature of phytoplankton responses, which differed among taxonomic groups (Fig. 3). Pigments from siliceous algae (fucoxanthin; Fig. 3a) showed 2 maxima during winter 2004–2005 (with peaks offset among treatments) and during the following growth period spanning from April to June 2005 for this group. Pigments from chlorophytes (Chl-b; Fig. 3c) were abundant throughout the year of sampling. By contrast, pigments from cryptophytes (alloxanthin; Fig. 3b) and cyanobacteria (echinenone; Fig. 3d) were much more prevalent later in the experiment and after the increase in stickleback biomass (dashed line). Cryptophyte pigments increased markedly after June 2005, whereas maximum concentrations of cyanobacterial pigments developed for a shorter period between April and June 2005. Responses of Chl-a (Fig. 3e) to treatments integrated the patterns in the individual algal pigments; consequently, timing of total phytoplankton responses was variable among treatments, reflecting the unique responses of individual phytoplankton groups. Because fish were added in spring of the second year (dashed line), changes in biomass of Daphnia spp. are presented to assess any shifts in grazing potential that could have influenced phytoplankton biomass. As reported in Barker et al. (2008a), Daphnia biomass was significantly suppressed by higher salinities, but only during the “high fish” period (Fig. 3). By contrast, no significant effects of N treatments were detected on Daphnia biomass. Across the experiment, mean Daphnia biomass was more regularly recorded as zero after fish biomass had increased.