1
|
Chen F, Ma J, Pan K. Synergistic effect of silicon availability and salinity on metal adsorption in a common estuarine diatom. J Environ Sci (China) 2025; 148:364-374. [PMID: 39095171 DOI: 10.1016/j.jes.2024.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 08/04/2024]
Abstract
Increasing nitrogen and phosphorus discharge and decreasing sediment input have made silicon (Si) a limiting element for diatoms in estuaries. Disturbances in nutrient structure and salinity fluctuation can greatly affect metal uptake by estuarine diatoms. However, the combined effects of Si and salinity on metal accumulation in these diatoms have not been evaluated. In this study, we aimed to investigate how salinity and Si availability combine to influence the adsorption of metals by a widely distributed diatom Phaeodactylum tricornutum. Our data indicate that replete Si and low salinity in seawater can enhance cadmium and copper adsorption onto the diatom surface. At the single-cell level, surface potential was a dominant factor determining metal adsorption, while surface roughness also contributed to the higher metal loading capacity at lower salinities. Using a combination of non-invasive micro-test technology, atomic force microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, we demonstrate that the diversity and abundance of the functional groups embedded in diatom cell walls vary with salinity and Si supply. This results in a change in the cell surface potential and transient metal influx. Our study provides novel mechanisms to explain the highly variable metal adsorption capacity of a model estuarine diatom.
Collapse
Affiliation(s)
- Fengyuan Chen
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Jie Ma
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Ke Pan
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
| |
Collapse
|
2
|
Kumar M, Tibocha-Bonilla JD, Füssy Z, Lieng C, Schwenck SM, Levesque AV, Al-Bassam MM, Passi A, Neal M, Zuniga C, Kaiyom F, Espinoza JL, Lim H, Polson SW, Allen LZ, Zengler K. Mixotrophic growth of a ubiquitous marine diatom. SCIENCE ADVANCES 2024; 10:eado2623. [PMID: 39018398 PMCID: PMC466952 DOI: 10.1126/sciadv.ado2623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/12/2024] [Indexed: 07/19/2024]
Abstract
Diatoms are major players in the global carbon cycle, and their metabolism is affected by ocean conditions. Understanding the impact of changing inorganic nutrients in the oceans on diatoms is crucial, given the changes in global carbon dioxide levels. Here, we present a genome-scale metabolic model (iMK1961) for Cylindrotheca closterium, an in silico resource to understand uncharacterized metabolic functions in this ubiquitous diatom. iMK1961 represents the largest diatom metabolic model to date, comprising 1961 open reading frames and 6718 reactions. With iMK1961, we identified the metabolic response signature to cope with drastic changes in growth conditions. Comparing model predictions with Tara Oceans transcriptomics data unraveled C. closterium's metabolism in situ. Unexpectedly, the diatom only grows photoautotrophically in 21% of the sunlit ocean samples, while the majority of the samples indicate a mixotrophic (71%) or, in some cases, even a heterotrophic (8%) lifestyle in the light. Our findings highlight C. closterium's metabolic flexibility and its potential role in global carbon cycling.
Collapse
Affiliation(s)
- Manish Kumar
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Juan D. Tibocha-Bonilla
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Zoltán Füssy
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Chloe Lieng
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Sarah M. Schwenck
- Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Alice V. Levesque
- Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Mahmoud M. Al-Bassam
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Anurag Passi
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Maxwell Neal
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Cristal Zuniga
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Farrah Kaiyom
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Josh L. Espinoza
- Department of Microbial and Environmental Genomics, J. Craig Venter Institute, 4120 Capricorn Way, La Jolla, CA 92037, USA
| | - Hyungyu Lim
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Shawn W. Polson
- Department of Computer and Information Sciences, University of Delaware, 18 Amstel Ave., Newark, DE 19716, USA
- Center for Bioinformatics and Computational Biology, University of Delaware, 590 Avenue 1743, Newark, DE 19713, USA
| | - Lisa Zeigler Allen
- Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
- Department of Microbial and Environmental Genomics, J. Craig Venter Institute, 4120 Capricorn Way, La Jolla, CA 92037, USA
| | - Karsten Zengler
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
- Center for Microbiome Innovation, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
- Program in Materials Science and Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| |
Collapse
|
3
|
Li Y, Zhang C, Hu Z. Hydraulic retention time governed the micro/nanostructures of titanium-incorporated diatoms and their photocatalytic activity. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123398. [PMID: 38272163 DOI: 10.1016/j.envpol.2024.123398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 01/04/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024]
Abstract
Titanium-incorporated diatoms are promising biomaterials to photodegrade micropollutants such as pharmaceuticals and personal care products (PPCPs). Hydraulic retention time (HRT) is a key parameter for diatom cultivation and the incorporation of titanium into diatom frustules. This study assessed how HRT governs the micro/nanostructures, titania (TiO2) content and distribution, and the photocatalytic activity of titanium-incorporated diatom frustules. We cultivated a diatom strain Stephanodiscus hantzschii using a feed solution containing titanium(IV) in membrane bioreactors (MBRs) at a solids retention time (SRT) of 10 d and staged HRTs from 24 to 12 and to 6 h. The decrease in HRT reduced the porosity of diatom frustules but increased their silicon and titania contents. When the HRT decreased from 24 to 12 and to 6 h, the specific surface areas of the diatom decreased from 37.65 ± 3.19 to 31.53 ± 3.71 and to 18.43 ± 2.69 m2·g-1 frustules, while the titanium (Ti) contents increased from 53 ± 14 to 71 ± 9 and to 85 ± 13 mg Ti·g-1 frustules. The increase in the influent flow rates of the MBRs with decreasing HRTs likely enhanced nutrient diffusion inside the diatom valve pores, facilitating the uptake and incorporation of silicon and titanium. The titanium-incorporated frustules were effective in removing two representative PPCPs, bisphenol A (BPA) and N,N-diethyl-meta-toluamide (DEET), from water. As photocatalytic activity depends on the amount of titanium, decreasing the HRT substantially increased the photocatalytic activity of the titanium-incorporated frustules. In batch tests under ultraviolet light, frustules from the diatom cultivated at HRTs of 24, 12, and 6 h had the pseudo-first-order removal (mainly through photodegradation) rate constants of BPA of 0.376, 0.456, and 0.683 h-1, respectively. Under the same experimental condition, the pseudo-first-order removal rate constants of DEET by the frustules cultivated at HRTs of 24, 12, and 6 h increased from 0.270 to 0.330 and to 0.480 h-1.
Collapse
Affiliation(s)
- Yan Li
- NingboTech University, Ningbo, 315000, China; Department of Civil & Environmental Engineering, University of Missouri, Columbia, MO, 65211, United States
| | - Chiqian Zhang
- Civil Engineering Program, College of Engineering & Computer Science, Arkansas State University, Arkansas, 72467, United States.
| | - Zhiqiang Hu
- Department of Civil & Environmental Engineering, University of Missouri, Columbia, MO, 65211, United States
| |
Collapse
|
4
|
Zhang Z, Ma J, Chen F, Chen Y, Pan K, Liu H. Mechanisms underlying the alleviated cadmium toxicity in marine diatoms adapted to ocean acidification. JOURNAL OF HAZARDOUS MATERIALS 2024; 463:132804. [PMID: 37890381 DOI: 10.1016/j.jhazmat.2023.132804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/29/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023]
Abstract
Anthropogenic activities have significantly increased the influx of carbon dioxide and metals into the marine environment. Combining ocean acidification (OA) and metal pollution may lead to unforeseen biological and ecological consequences. Several studies have shown that OA reduces cadmium (Cd) toxicity in marine diatoms. Although these studies have shed light on the physiological and transcriptomic responses of diatoms exposed to Cd, many aspects of the mechanisms underlying the reduced metal accumulation in diatoms remain unknown. This study aims to address this unresolved question by comparing Cd subcellular distribution, antioxidant enzyme activity, relative expression of metal transporters, surface potential, surface composition, and transmembrane potential in the diatom Phaeodactylum tricornutum grown under ambient and 1200 µatm pCO2 conditions. Our findings reveal that diatoms grown in acidified seawater exhibit higher surface potential and higher plasma membrane depolarization. These changes and the competing effects of increased H+ concentration result in a blunted response of P. tricornutum to the Cd challenge. Consequently, this study offers a new explanation for mitigating Cd toxicity by marine diatoms adapted to OA.
Collapse
Affiliation(s)
- Zhen Zhang
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, China; Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region
| | - Jie Ma
- Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Fengyuan Chen
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, China; Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region
| | - Yingya Chen
- Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Ke Pan
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, China; Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced Study, Shenzhen University, Shenzhen, China.
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region; Hong Kong Branch of Southern Marine Science & Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region.
| |
Collapse
|
5
|
Chen F, Ma J, Zhong Z, Liu H, Miao A, Zhu X, Pan K. Silicon Limitation Impairs the Tolerance of Marine Diatoms to Pristine Microplastics. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3291-3300. [PMID: 36799767 DOI: 10.1021/acs.est.2c09305] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Marine diatoms are currently facing increasing threats from microplastic (MP) pollution that is intertwined with the disturbed nutrient stoichiometry in seawater. The effects of nutrient imbalances such as silicon (Si) limitation on the interactions between diatoms and MPs remain poorly understood. In contrast to previous studies which mainly focused on MP toxicity, this study emphasizes how Si availability affects nano-scale interactions between pristine polystyrene MPs and diatom surfaces. Results showed that Si-starved cells were less tolerant to MP toxicity than the Si-enriched counterparts. Si limitation significantly changed the configuration and chemical composition of the perforated frustules, forming less negatively charged, more adhesive, and mechanically weaker cells. All of these changes facilitated the adsorption and hetero-aggregation between the diatom cells and MPs and compromised the diatoms' resistance to MP attack. Our study provides novel insights into the effects of pristine MPs in the marine environment under the context of dynamic nutrient conditions.
Collapse
Affiliation(s)
- Fengyuan Chen
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, Guangdong Province, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, Guangdong Province, China
| | - Jie Ma
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, Guangdong Province, China
| | - Zihan Zhong
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, Guangdong Province, China
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong 999077, Special Administrative Region, China
| | - Aijun Miao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu Province 210023, China
| | - Xiaoshan Zhu
- College of Ecology and Environment, Hainan University, Haikou 570228, Hainan, China
| | - Ke Pan
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, Guangdong Province, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, Guangdong Province, China
| |
Collapse
|
6
|
Sharma D, Biswas H, Chowdhury M, Silori S, Pandey M, Ray D. Phytoplankton community shift in response to experimental Cu addition at the elevated CO 2 levels (Arabian Sea, winter monsoon). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:7325-7344. [PMID: 36038690 DOI: 10.1007/s11356-022-22709-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
Understanding phytoplankton community shifts under multiple stressors is becoming increasingly important. Among other combinations of stressors, the impact of trace metal toxicity on marine phytoplankton under the ocean acidification scenario is an important aspect to address. Such multiple stressor studies are rare from the Arabian Sea, one of the highest productive oceanic provinces within the North Indian Ocean. We studied the interactive impacts of copper (Cu) and CO2 enrichment on two natural phytoplankton communities from the eastern and central Arabian Sea. Low dissolved silicate (DSi < 2 µM) favoured smaller diatoms (e.g. Nitzschia sp.) and non-diatom (Phaeocystis). CO2 enrichment caused both positive (Nitzschia sp. and Phaeocystis sp.) and negative (Cylindrotheca closterium, Navicula sp., Pseudo-nitzschia sp., Alexandrium sp., and Gymnodinium sp.) growth impacts. The addition of Cu under the ambient CO2 level (A-CO2) hindered cell division in most of the species, whereas Chla contents were nearly unaffected. Interestingly, CO2 enrichment seemed to alleviate Cu toxicity in some species (Nitzschia sp., Cylindrotheca closterium, Guinardia flaccida, and Phaeocystis) and increased their growth rates. This could be related to the cellular Cu demand and energy budget at elevated CO2 levels. Dinoflagellates were more sensitive to Cu supply compared to diatoms and prymnesiophytes and could be related to the unavailability of prey. Such community shifts in response to the projected ocean acidification, oligotrophy, and Cu pollution may impact trophic transfer and carbon cycling in this region.
Collapse
Affiliation(s)
- Diksha Sharma
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India
- Affiliated for PhD Under Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India
| | - Haimanti Biswas
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
| | - Mintu Chowdhury
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India
- School of Oceanographic Studies, Jadavpur University, Kolkata, 700032, India
| | - Saumya Silori
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Medhavi Pandey
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Durbar Ray
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403004, India
| |
Collapse
|
7
|
Roychoudhury P, Bose R, Dąbek P, Witkowski A. Photonic Nano-/Microstructured Diatom Based Biosilica in Metal Modification and Removal-A Review. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6597. [PMID: 36233939 PMCID: PMC9572592 DOI: 10.3390/ma15196597] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/11/2022] [Accepted: 09/19/2022] [Indexed: 05/30/2023]
Abstract
The siliceous exoskeletal shells of diatoms, commonly known as frustules, have drawn attention because of their photoluminescence property and high volume to surface area. Photonic biosilica can also enhance the plasmonic sensitivity of nanoparticles. Because of this, researchers have studied the effectiveness of various metal particles after combining with biosilica. Additionally, naturally occurring diatom-based biosilica has excellent adsorption and absorption capabilities, which have already been exploited for wastewater treatment. Moreover, the nanoporous, ultra-hydrophilic frustules can easily accumulate more molecules on their surfaces. As a consequence, it becomes easier to conjugate noble metals with silica, making them more stable and effective. The main focus of this review is to agglomerate the utility of biocompatible diatom frustules, which is a no-cost natural resource of biosilica, in metal modification and removal.
Collapse
Affiliation(s)
- Piya Roychoudhury
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland
| | - Rahul Bose
- Department of Botany, University of Calcutta, Ballygunge Circular Road 35, Kolkata 700019, India
| | - Przemysław Dąbek
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland
| | - Andrzej Witkowski
- Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16a, 70-383 Szczecin, Poland
| |
Collapse
|
8
|
Toxic Effect of Metal Doping on Diatoms as Probed by Broadband Terahertz Time-Domain Spectroscopy. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27185897. [PMID: 36144633 PMCID: PMC9504612 DOI: 10.3390/molecules27185897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/04/2022] [Accepted: 09/06/2022] [Indexed: 11/19/2022]
Abstract
The global marine environment is increasingly affected by human activities causing climate change, eutrophication, and pollution. These factors influence the metabolic mechanisms of phytoplankton species, such as diatoms. Among other pollutant agents, heavy metals can have dramatic effects on diatom viability. Detailed knowledge of the interaction of diatoms with metals is essential from both a fundamental and applicative point of view. To this aim, we assess terahertz time-domain spectroscopy as a tool for sensing the diatoms in aqueous systems which mimic their natural environment. Despite the strong absorption of terahertz radiation in water, we show that diatoms can be sensed by probing the water absorption enhancement in the terahertz range caused by the water–diatom interaction. We reveal that the addition of metal dopants affects this absorption enhancement, thus enabling the monitoring of the toxic effects of metals on diatoms using terahertz spectroscopy. We demonstrate that this technique can detect the detrimental effects of heavy metals earlier than conventional methods such as microscopy, enzymatic assays, and molecular analyses aimed at assessing the overexpression of genes involved in the heavy metal-stress response.
Collapse
|
9
|
Sengupta A, Chakraborty I, G I, Mazumder N. An insight into the physicochemical characterisation of starch-lipid complex and its importance in food industry. FOOD REVIEWS INTERNATIONAL 2022. [DOI: 10.1080/87559129.2021.2021936] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Aditi Sengupta
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Ishita Chakraborty
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Indira G
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Nirmal Mazumder
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| |
Collapse
|
10
|
Potential for Biomass Production and Remediation by Cultivation of the Marine Model Diatom Phaeodactylum tricornutum in Oil Field Produced Wastewater Media. WATER 2021. [DOI: 10.3390/w13192700] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
While oilfield produced water (PW) is one of the largest, unclaimed wastewater streams of the oil industry, it could potentially be used as a cultivation medium for microalgae. Microalgae could help with the remediation of this water while also delivering biomass that can be transformed into valuable byproducts such as biofuels. The coupling of these two purposes is expected to cut production costs of biofuels while aiding environmental protection. In this study, we compared the cultivation capacity of the marine model diatom Phaeodactylum tricornutum in media at varying salinities and in media composed of PW from two oilfields in the Central Valley of California that differed drastically in the concentration of inorganic and organic constituents. Specifically, we measured the carrying capacity of these media, the maximum growth rates of P. tricornutum, its cellular lipid accumulation capacity, and its capacity to remediate the most polluted PW source. Our study shows that P. tricornutum can successfully adjust to the tested cultivation media through processes of short-term acclimation and long-term adaptation. Furthermore, the cultivation of P. tricornutum in the most heavily polluted PW source led to significant increases in cell yield and improved photosynthetic capacity during the stationary phase, which could be attributed chiefly to the higher levels of nitrate present in this PW source. Chemical water analyses also demonstrated the capability of P. tricornutum to remediate major nutrient content and potentially harmful elements like fluorine and copper. Because P. tricornutum is amenable to advanced genetic engineering, which could be taken advantage of to improve its cultivation resilience and productivity in an economic setting, we propose this study as a step towards essential follow-up studies that will identify the genetic regulation behind its growth in oilfield PW media and its remediation of the PW constituents.
Collapse
|
11
|
Ma J, Zhou B, Chen F, Pan K. How marine diatoms cope with metal challenge: Insights from the morphotype-dependent metal tolerance in Phaeodactylum tricornutum. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111715. [PMID: 33396046 DOI: 10.1016/j.ecoenv.2020.111715] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 11/14/2020] [Accepted: 11/22/2020] [Indexed: 06/12/2023]
Abstract
Metal tolerance in marine diatoms vary between morphotypes, strains, and species due to their long-term adaptations to stochastic environments. The mechanisms underlying this highly variable trait remain a matter of interest in ecotoxicology. In this study, we used several cutting-edge techniques, including a non-invasive micro-test technique, atomic force microscopy, and X-ray photoelectron spectroscopy to examine cadmium (Cd) accumulation and tolerance in the three morphotypes of Phaeodactylum tricornutum. Subcellular Cd distribution, metal transporter expression, and glutathione and phytochelatin activity were also analyzed to characterize the morphology-dependent Cd homeostasis and detoxification. We found that the oval morphotype accumulated more Cd, but was also more Cd tolerant than the other morphotypes. The greater surface binding of Cd to the oval morphotype is attributable to its smaller spherical form, rougher cell surface, and lower surface potential. Moreover, the oval morphotype was less permeable to Cd ions and contained higher phytochelatin and glutathione levels, which explained its higher metal tolerance. Our study offers new explanations for diatom's adaptations to changing environments that may contribute to its evolutionary success.
Collapse
Affiliation(s)
- Jie Ma
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Beibei Zhou
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Fengyuan Chen
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Ke Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
| |
Collapse
|