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Effects of dietary lead exposure on vitamin levels in great tit nestlings – An experimental manipulation
2016
Ruiz, Sandra | Espín, Silvia | Rainio, Miia | Ruuskanen, Suvi | Salminen, Juha-Pekka | Lilley, Thomas M. | Eeva, Tapio
Exposure to metal pollution negatively affects animal physiology, including nutrient metabolism, but in the wild an effect can seldom be attributed to a single metal. Moreover, little is known about how the metabolism of vitamins, essential micronutrients for developing juveniles, is affected by toxic metals. Therefore we experimentally investigated the effects of lead (Pb), a widespread toxic metal, on four fat-soluble vitamins A (total and retinol), D3, E (total and α-tocopherol) and K and carotenoids (lutein, zeaxanthin and unidentified) in great tit (Parus major) nestlings. In addition to a control group where no Pb was provided, two Pb-dosed groups were compared to a metal exposed group in the vicinity of a Ni–Cu smelter. We examined whether Pb treatment affects vitamin homeostasis and how the response of Pb-treated birds relates to that of a population under industrial exposure of Pb and other metals. For this purpose, vitamin and carotenoid levels were quantified with UPLC-MS from plasma of 7 days-old nestlings. All metal exposed groups showed increased vitamin A and retinol levels. However, vitamin levels were not directly associated with fecal Pb levels, with the exception of retinol, which was positively correlated with fecal Pb. Alpha-tocopherol, lutein and zeaxanthin levels were positively associated with body mass and wing growth rate. To conclude, Pb exposure increased plasma vitamin A and retinol levels while the levels of other vitamins and carotenoids rather reflected secondary pollution effects via differences in habitat and diet quality at the smelter site. Our findings suggest Pb exposed nestlings may allocate the vitamins needed for growth and development to fight the physiological stress thus compromising their fitness.
显示更多 [+] 显示较少 [-]Photosynthesis, chloroplast pigments, and antioxidants in Pinus canariensis under free-air ozone fumigation
2009
Then, Ch | Herbinger, K. | Luis, V.C. | Heerdt, C. | Matyssek, R. | Wieser, G.
High O3 levels, driving uptake and challenging defense, prevail on the Canary Islands, being associated with the hot and dry summers of the Mediterranean-type climate. Pinus canariensis is an endemic conifer species that forms forests across these islands. We investigated the effects of ozone on photosynthesis and biochemical parameters of P. canariensis seedlings exposed to free-air O3 fumigation at Kranzberg Forest, Germany, where ambient O3 levels were similar to those at forest sites in the Canary Islands. The twice-ambient O3 regime (2xO3) neither caused visible injury-like chlorotic or necrotic spots in the needles nor significantly affected violaxanthin, antheraxanthin and zeaxanthin levels and the de-epoxidation state of the xanthophyll cycle. In parallel, stomatal conductance for water vapour, net photosynthesis, intercellular CO2 concentration, chlorophyll fluorescence parameters, as well as antioxidant levels were hardly affected. It is concluded that presently prevailing O3 levels do not impose severe stress on P. canariensis seedlings.
显示更多 [+] 显示较少 [-]Nutrient concentrations and distribution of phytoplankton pigments in recently deposited sediments of a positive tropical estuary
2021
Mathew, Jose | Singh, Archana | Gopinath, Anu
Investigation of nutrients in the water column and phytoplankton pigments in recently formed modern sediments (0–5 cm) was carried out in Cochin estuary. The anthropogenic impacts were assessed using nutrients, nitrate, and phosphate in combination with phytopigments in sediments. The nitrate and phosphate concentration during the study ranged from 0.81 to 42.53 μmol/L and from 0.1 to 5.81 μmol/L, respectively. The mean values of the pigment showed the following order: zeaxanthin (791.53 ng/g) > lutein (347.57 ng/g) > fucoxanthin (335.30 ng/g) > pheophytin (308.84 ng/g) > pheophorbide (172.06 ng/g) > chlorophyll a (161.63 ng/g). The increase in the concentration of zeaxanthin indicated the presence of cyanobacteria, associated with eutrophication. Correlation analysis revealed that water column nutrients have a strong relationship between fucoxanthin and lutein, indicating the coexistence of diatoms and prasinophytes in the sampling sites. The principal component analysis showed positive loading of nutrients concomitant with pigment fucoxanthin and lutein, thus establishing that nutrient input controls the phytoplankton biomass of this estuary.
显示更多 [+] 显示较少 [-]A baseline investigation of phytoplankton pigment composition in contrasting coastal ecosystems of north-western Bay of Bengal
2020
Srichandan, Suchismita | Baliarsingh, Sanjiba Kumar | Lotliker, Aneesh Anandrao | Prakash, Satya | Samanta, Alakes | Sahu, Kali Charan
A baseline investigation of the chromatographic characterization of phytoplankton pigments with complementing microscopy was conducted in Mahanadi estuary, Chilika lagoon, and coastal waters off Gopalpur along the east coast of India. Marker pigments specific to different phytoplankton groups have been discerned in these contrasting coastal ecosystems. A total of 16 phytoplankton pigments were identified. Irrespective of seasons, Chilika lagoon was characterized by a high concentration of zeaxanthin, indicating the predominance of picocyanobacteria. Zeaxanthin and fucoxanthin were the major diagnostic pigments in Mahanadi estuary during monsoon and other seasons, respectively. In coastal waters off Gopalpur, algal blooms resulted in a higher concentration of fucoxanthin during pre-monsoon and monsoon season. The pigment ratios were comparatively higher for Chilika lagoon than for Mahanadi estuary and off Gopalpur, irrespective of seasons. The present study highlights the advantages of the chromatography technique in identifying small-sized phytoplankton in coastal ecosystems in comparison to conventional microscopy.
显示更多 [+] 显示较少 [-]Geochemistry and sedimentary photopigments as proxies to reconstruct past environmental changes in a subtropical reservoir
2022
Cardoso-Silva, Sheila | Mizael, Juliana Oliveira Soares Silva | Frascareli, Daniele | Figueira, Rubens César Lopes | Pompêo, Marcelo | Vicente, Eduardo | Moschini-Carlos, Viviane
Sediment cores were used to establish past environmental impacts associated with eutrophication, erosion and metal contamination in the subtropical Atibainha reservoir (São Paulo State, Brazil). We hypothesize that: (1) the levels of nutrients, determined by a spectrophotometric method, reflect the contributions of these elements over time and (2) changes in sedimentation rates, determined by ²¹⁰Pb geochronology, and metal flows, determined by ICP-AEOS, are related to anthropic activities. Stratigraphic changes in the analysed variables were used to divide the sediment cores into three intervals, according to PCA and cluster analysis (Euclidian distances, Ward’s method). Interval I, composed by the period prior to operation of the reservoir, was influenced by organic matter levels. Interval II, between 1967 and 1993 (PC2: 14.94% of the total variability), a period of minor impacts, was mainly influenced by Mn (eigenvalue of 0.71) and Zn (0.74). Interval III, which included sediment deposited between 1993 and 2015 (PC1: 60.28% of the total variability), was influenced by the highest levels of the pigments lutein (0.86), zeaxanthin (0.90) and fucoxanthin (0.65), together with total nitrogen (0.78) and sedimentation rate (0.91), suggesting changes in the phytoplankton community composition probably associated to the intensification of eutrophication and erosion processes. Despite the limitations of applying paleolimnological techniques in reservoirs and the use of pigments as proxies in regions with higher temperatures, it was observed that the anoxic conditions and the aphotic environment in the hypolimnion acted to preserve pigments associated with the groups Chlorophyta (lutein), Cyanobacteria (zeaxanthin) and Bacillariophyta (fucoxanthin). The isolated analysis of nutrients was not sufficient to make conclusive inferences regarding the eutrophication history, since the levels of TP tended to decrease over time, in contrast to an increase in the levels of TN. Despite intensification of eutrophication and erosion, associated to anthropic activities, no signs of metal contamination were recorded.
显示更多 [+] 显示较少 [-]Benthic-pelagic coupling assessed using phytoplankton marker pigments: a case study from the Paradip port, East Coast of India
2022
Krishnan, Sathish | Patil, Jagadish Siddalingappa | Anil, Arga Chandrashekar
This study addresses the seasonal distribution of phytoplankton marker pigments (PMP) and the ratios (indicating freshness and fate) from water and surface sediments from the coastal port ecosystem (Paradip port, Odisha, east coast of India) and its utility in understanding phytoplankton pelagic-benthic linkages. Chlorophyll and PMP (for different groups and degradation) distribution revealed distinct seasonality, but the seasonal trend was different for water and sediments. High and low values were observed in the water column during inter-monsoons (fall/spring) and monsoons (southwest/northeast), respectively, whereas, in sediments, the reverse was recorded. However, the contribution of group-specific PMP was different: fucoxanthin > chlorophyll b > zeaxanthin > alloxanthin > peridinin dominated in water and chlorophyll b > zeaxanthin > fucoxanthin > alloxanthin > peridinin in sediment. Selective grazing and stability of sedimentary PMP (fucoxanthin, diatoms PMP, is least stable than other groups) could contribute to such differences. Relatively high chlorophyll:pheopigment ratios in the water and low pheophorbide: pheophytin in sediments indicated the dominance of actively growing microalgae and chlorophyll degradation via chlorophyllidae pathway in the water but not in sediments. These findings suggest that (i) much of the phytoplankton (primarily diatoms) is lost due to herbivory before reaching bottom sediments, and (ii) pigment contribution is determined by selective grazing in water and PMP decay constants in sediments. Documenting such information will give new insights into ecosystem assessment and algal bloom research.
显示更多 [+] 显示较少 [-]Isolation, purification, and identification of antialgal substances in green alga Ulva prolifera for antialgal activity against the common harmful red tide microalgae
2016
Sun, Ying-ying | Wang, Hui | Guo, Gan-lin | Pu, Yin-fang | Yan, Bin-lun | Wang, Chang-hai
Ten compounds (1~10) were successfully isolated from green algae Ulva prolifera through the combination of silica gel column chromatography, Sephadex LH-20 column chromatography and repeated preparative thin-layer chromatography. These ten compounds showed antialgal activity against red tide microalgae. Among them, compounds 3, 6, and 7 showed stronger antialgal activity against red tide microalgae. Furthermore, their structure was identified on the basis of spectroscopic data. There are three glycoglycerolipids: 1-O-octadecanoic acid-3-O-β-D-galactopyranosyl glycerol (2), 1-O-palmitoyl-3-O-β-D-galactopyranosyl glycerol (4), and 1-O-palmitoyl-2-O-oleoyl-3-O-β-D-galactopyranosyl glycerol (5); two monoglycerides: glycerol monopalmitate (1), 9-hexadecenoic acid, 2,3-dihydroxypropyl ester (3); two terpenoids: loliolide (6) and lsololiolide (7); one lipid-soluble pigments: zeaxanthin (8); one sterol: cholest-5-en-3-ol (9); and one alkaloid: pyrrolopiperazine-2,5-dione (10). These compounds were isolated from U. prolifera for the first time, and compounds 2, 3, 5, and 8 were isolated from marine macroalgae for the first time.
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