Prospects in Cadmium-Contaminated Water Management Using Free-Living Cyanobacteria (Oscillatoria sp.)

In this study, the removal of cadmium (Cd) by free-living Oscillatoria sp. was studied. Our results showed that maximal Cd removal efficiency (~60%) by the cyanobacterial culture was achieved within 12–24 h in the presence of 5.0 or 25.0 mg/L of Cd. The mechanisms underlying this phenomenon were explored by elemental analysis and FTIR-ATR spectroscopy. It was found that metal adsorption by negatively charged functional groups in the cyanobacterial biomass was the main mechanism used by Oscillatoria sp. to remove metal from the aqueous medium, followed by Cd bioaccumulation into living cells. Additionally, Cd-exposed microalgae showed increased oxidative stress (MDA formation), a decreased dehydrogenase activity, a higher amount of soluble carbohydrates and a decreased total carotenoid concentration, as compared to the control cells. These results suggest that Oscillatoria sp. improved its antioxidative defense system under stressful conditions, through carotenoid-mediated ROS quenching and induction of carbohydrate catabolism, in order to counteract the oxidative damage and preserve the photosynthetic machinery and cellular energetics. In fact, no significant reduction in Oscillatoria sp. cell density, total protein amount, and chlorophyll a content was observed after 24-h Cd exposure, even at the highest metal concentration tested (i.e., 25.0 mg/L). Hence, the presented results are the first to describe some new insights about the metabolic and physiological behavior of living Oscillatoria sp. during Cd remediation, and open up the possibility of finding an equilibrium that maximizes metal removal performance with an active cyanobacterial metabolism, to achieve a rewarding and sustainable management of industrial metal-polluted wastewater.

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A Physiological Comparison of the Symbiotic Alga Platymonas Convolutae and its Free-Living Relatives

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400000710 ◽

1970 ◽

Vol 50 (1) ◽

pp. 199-208 ◽

Cited By ~ 23

Author(s):

G. W. Gooday

Keyword(s):

Recent Work ◽

Pure Culture ◽

Type Species ◽

Organic Nitrogen ◽

Soluble Carbohydrates ◽

Symbiotic Relationship ◽

Symbiotic Alga ◽

Free Living ◽

Unialgal Culture ◽

Convoluta Roscoffensis

Platymonas convolutae Parke et Manton is the natural algal partner of the symbiotic worm Convoluta roscoffensis Graff (Parke & Manton 1967). Recent work by Provasoli, Yamasu & Manton (1968) has shown that although several algae can form a symbiotic relationship with the worm if supplied in unialgal culture, the natural symbiont is the most effective and is able to eliminate competitors. The alga can be cultured in a denned medium away from its partner, and this paper presents some physiological characteristics of the alga in pure culture in comparison with some of its free-living relatives, in particular the type species of the genus Platymonas, P. tetrathele G. S. West. The present investigation has been concerned mainly with the uptake of carbohydrates and the utilization of organic nitrogen. Other aspects that are included are the excretion of metabolites into the medium and the soluble carbohydrates found within the algae. In addition, culturing the algae has revealed a difference in behaviour of possible relevance to the symbiotic relationship.

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Nematode parasites reduce carotenoid-based signalling in male red grouse

Biology Letters ◽

10.1098/rsbl.2006.0593 ◽

2007 ◽

Vol 3 (2) ◽

pp. 161-164 ◽

Cited By ~ 61

Author(s):

Jesús Martínez-Padilla ◽

François Mougeot ◽

Lorenzo Pérez-Rodríguez ◽

Gary R Bortolotti

Keyword(s):

Nematode Parasite ◽

Negative Effects ◽

Free Living ◽

Red Grouse ◽

Carotenoid Concentration ◽

Nematode Parasites ◽

Parasite Infections ◽

Lagopus Lagopus Scoticus ◽

Trichostrongylus Tenuis ◽

First Time

Carotenoids determine the yellow–red colours of many ornaments, which often function as signals of quality. Carotenoid-based signalling may reliably advertise health and should be particularly sensitive to parasite infections. Nematodes are among the commonest parasites of vertebrates, with well-documented negative effects on their hosts. However, to date, little is known about the effects that these parasites may have on carotenoid-based signalling. Tetraonid birds (grouse) exhibit supra-orbital combs, which are bright integumentary ornaments pigmented by carotenoids. We tested the effect of the nematode parasite Trichostrongylus tenuis on signalling in free-living male red grouse Lagopus lagopus scoticus . We show that experimentally reduced nematode infection increases plasma carotenoid concentration and comb redness, demonstrating for the first time that nematodes can influence carotenoid-based signals.

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Mycoextraction: Rapid Cadmium Removal by Macrofungi-Based Technology from Alkaline Soil

Minerals ◽

10.3390/min8120589 ◽

2018 ◽

Vol 8 (12) ◽

pp. 589

Author(s):

Miaomiao Chen ◽

Likun Wang ◽

Junliang Hou ◽

Shushen Yang ◽

Xin Zheng ◽

...

Keyword(s):

Soil Solution ◽

Removal Efficiency ◽

Fruiting Body ◽

Metal Removal ◽

Heavy Metal Removal ◽

Continuous Optimization ◽

Alkaline Soil ◽

Cadmium Removal ◽

Intracellular Binding ◽

Cd Removal

Fungi are promising materials for soil metal bioextraction and thus biomining. Here, a macrofungi-based system was designed for rapid cadmium (Cd) removal from alkaline soil. The system realized directed and rapid fruiting body development for subsequent biomass harvest. The Cd removal efficiency of the system was tested through a pot culture experiment. It was found that aging of the added Cd occurred rapidly in the alkaline soil upon application. During mushroom growth, the soil solution remained considerably alkaline, though a significant reduction in soil pH was observed in both Cd treatments. Cd and dissolved organic carbon (DOC) in soil solution generally increased over time and a significant correlation between them was detected in both Cd treatments, suggesting that the mushroom‒substratum system has an outstanding ability to mobilize Cd in an alkaline environment. Meanwhile, the growth of the mushrooms was not affected relative to the control. The estimated Cd removal efficiency of the system was up to 12.3% yearly thanks to the rapid growth of the mushroom and Cd enrichment in the removable substratum. Transcriptomic analysis showed that gene expression of the fruiting body presented considerable differences between the Cd treatments and control. Annotation of the differentially expressed genes (DEGs) indicated that cell wall sorption, intracellular binding, and vacuole storage may account for the cellular Cd accumulation. In conclusion, the macrofungi-based technology designed in this study has the potential to become a standalone biotechnology with practical value in soil heavy metal removal, and continuous optimization may make the system useful for biomining.

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Functionalization and Evaluation of Inorganic Adsorbents for the Removal of Cadmium in Wastewater

Molecules ◽

10.3390/molecules26144150 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4150

Author(s):

Ana Lucía Campaña ◽

Amaimen Guillén ◽

Ricardo Rivas ◽

Veronica Akle ◽

Juan C. Cruz ◽

...

Keyword(s):

Metal Removal ◽

Low Cost ◽

Heavy Metal Removal ◽

Batch Adsorption ◽

Adsorption Processes ◽

Pseudo Second Order ◽

Cd Adsorption ◽

Inorganic Adsorbents ◽

Influence Of Ph ◽

Cd Removal

This study presents the feasibility of using various functionalized substrates, Fe3O4 nanoparticles (NPs) and Al2O3 spheres, for the removal of Cd from aqueous solution. To improve the materials’ affinity to Cd, we explored four different surface modifications, namely (3-Aminopropyl) triethoxysilane (APTES), L-Cysteine (Cys) and 3-(triethoxysilyl) propylsuccinic anhydride (CAS). Particles were characterized by FTIR, FIB-SEM and DLS and studied for their ability to remove metal ions. Modified NPs with APTES proved to be effective for Cd removal with efficiencies of up to 94%, and retention ratios up to 0.49 mg of Cd per g of NPs. Batch adsorption experiments investigated the influence of pH, contact time, and adsorbent dose on Cd adsorption. Additionally, the recyclability of the adsorbent and its potential phytotoxicity and animal toxicity effects were explored. The Langmuir, Freundlich, pseudo-first-order and pseudo-second-order models were applied to describe the behavior of the Cd adsorption processes. The adsorption and desorption results showed that Fe3O4 NPs modified with APTES are promising low-cost platforms with low phytotoxicity for highly efficient heavy metal removal in wastewater.

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Enhanced removal of cadmium from wastewater with coupled biochar and Bacillus subtilis

Water Science & Technology ◽

10.2166/wst.2021.138 ◽

2021 ◽

Author(s):

Jing Ding ◽

Weiguang Chen ◽

Zilan Zhang ◽

Fan Qin ◽

Jing Jiang ◽

...

Keyword(s):

Heavy Metal ◽

Bacillus Subtilis ◽

Composite System ◽

Metal Removal ◽

Heavy Metal Removal ◽

Peanut Shell ◽

Corn Stalk ◽

Batch Tests ◽

Cd Removal ◽

Adsorption Stage

Abstract Shortcomings of individual biochar or microbial technologies often exist in heavy metal removal from wastewater and may be circumvented by coupled use of biochar and microorganisms. In this study, Bacillus subtilis and each of three biochars of different origins (corn stalk, peanut shell, and pine wood) were coupled forming composite systems to treat a cadmium (Cd, 50 mg/L) wastewater formulated with CdCl2 in batch tests. Biochar in composite system enhanced the activity and Cd adsorption of B. subtilis. Compared with single systems with Cd removal up to 33%, the composite system with corn stalk biochar showed up to 62% Cd removal, which was greater than the sum of respective single B. subtilis and biochar systems. Further analysis showed that the removal of Cd by the corn stalk composite system could be considered to consist of three successive stages, that is, the biochar-dominant adsorption stage, the B. subtilis-dominant adsorption stage, and the final biofilm formation stage. The final stage may have provided the composite system with the ability to achieve prolonged steady removal of Cd. The biochar-microorganism composite system shows a promising application for heavy metal wastewater treatment.

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Pengolahan Tanah Tercemar Logam Berat Pb dan Cd Menggunakan Biochar Sekam Padi dengan Variasi Ukuran Partikel

Jurnal Sains Teknologi & Lingkungan ◽

10.29303/jstl.v7i1.215 ◽

2021 ◽

Vol 7 (1) ◽

pp. 59-68

Author(s):

Harsena Hayas Fika ◽

Shinta Elystia ◽

Aryo Sasmita

Keyword(s):

Heavy Metals ◽

Particle Size ◽

Removal Efficiency ◽

Metal Removal ◽

Heavy Metal Removal ◽

Testing Time ◽

Rice Husks ◽

Living Things ◽

Removal Of Heavy Metals ◽

Cd Removal

Soil contamination by heavy metals lead (Pb) and cadmium (Cd) is a form of pollution that is very dangerous for living things. One of the efforts to cultivate polluted soil is the remediation method using biochar from rice husks. The purpose of this study was to analyze the effect of biochar particle size variations on the removal of heavy metals Pb and Cd on contaminated soil. Biochar is made by pyrolysis at 500 0C for 1 hour and flows 0.1 L / minute of N2 gas. This study used a variety of biochar particle sizes of 100 mesh, 60 mesh, 40 mesh and testing time every 10 days for 1 month. The results of this study were the highest Pb and Cd removal in the addition of biochar with a particle size of 100 mesh, namely with a Pb concentration of 91.32 mg / kg and a removal efficiency of 54.05% ; Cd concentration of 10.47 mg / kg and a removal efficiency of 47.36%. Based on the results obtained, it can be stated that the smaller the biochar particle size, the efficiency of heavy metal removal will increase.

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Role of Phytoremediation in Reducing Cadmium Toxicity in Soil and Water

Journal of Toxicology ◽

10.1155/2018/4864365 ◽

2018 ◽

Vol 2018 ◽

pp. 1-16 ◽

Cited By ~ 18

Author(s):

Pooja Mahajan ◽

Jyotsna Kaushal

Keyword(s):

Heavy Metal ◽

Metal Removal ◽

Cadmium Toxicity ◽

Heavy Metal Removal ◽

Cost Effective ◽

Cost Effective Approach ◽

Hyperaccumulating Plant ◽

Cd Removal ◽

Soil And Water

Heavy metals are a noxious form of pollutants present in soil and water. A new plant-based solar energy driven technology, phytoremediation, emerges as eco-friendly and cost-effective approach to remove heavy metal from various media with the help of hyperaccumulating plant species. This review paper aims to provide information on phytoremediation and its mechanisms for heavy metal removal especially to focus on Cadmium (Cd) metal and highlights the role of various hyperaccumulating plants for Cd metal remediation in soil and water. It complies various field case studies which play the important role in understanding the Cd removal through various plants. Additionally, it pinpoints several sources and the effects of Cd and other technologies used for Cd remediation. This paper provides the recent development in mechanisms of Cd hyperaccumulation by different plants, in order to motivate further research in this field.

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Ultrastructure of neuromuscular relationships in the canine heartworm (dirofilaria immitis)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143018 ◽

1986 ◽

Vol 44 ◽

pp. 278-279

Author(s):

W. L. Steffens ◽

Nancy B. Roberts ◽

J. M. Bowen

Keyword(s):

Dirofilaria Immitis ◽

Domestic Dogs ◽

Structural Description ◽

Pharmacological Effects ◽

Free Living ◽

Canine Heartworm ◽

The World ◽

Synaptic Region ◽

Muscle Innervation ◽

Insight Into

The canine heartworm is a common and serious nematode parasite of domestic dogs in many parts of the world. Although nematode neuroanatomy is fairly well documented, the emphasis has been on sensory anatomy and primarily in free-living soil species and ascarids. Lee and Miller reported on the muscular anatomy in the heartworm, but provided little insight into the peripheral nervous system or myoneural relationships. The classical fine-structural description of nematode muscle innervation is Rosenbluth's earlier work in Ascaris. Since the pharmacological effects of some nematacides currently being developed are neuromuscular in nature, a better understanding of heartworm myoneural anatomy, particularly in reference to the synaptic region is warranted.

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