查找使用阿拉丁产品的科研文献

The impacts of ZnO/g-C3N4/Fe3O4-mediated photocatalytic degradation products of norfloxacin on Chlorella vulgaris in a photocatalyst-microalgae synergistic system

Wei Liu,Jin Wang,Yan Hao,Qinghong Zhang,Kecun Ma,Mei Liu,Zhi Chen,Qingguo Chen

Norfloxacin (NFX) is a widely used antibiotic that poses a persistent threat to aquatic ecosystems. The combination of photocatalysis and microalgae has emerged as a promising strategy for antibiotic removal. However, current research predominantly focuses on optimizing photocatalytic conditions and overall system efficiency, often neglecting the dynamic physiological state of microalgae when exposed to the photocatalytic degradation products of NFX (PDPN), which is the mixture of intermediates after 2 h ZGF photocatalysis of 8 mg/L NFX. This study constructed a synergistic degradation system employing a ZnO/g-C 3 N 4 /Fe 3 O 4 (ZGF) composite photocatalyst and Chlorella vulgaris for PDPN removal. Within this synergistic system, our primary focus was on the microalgal activity when cultured in a medium prepared from the PDPN. The results indicated the degradation rate of PDPN reached 82.1% in the synergistic degradation system. Transcriptomic analysis revealed that microalgae exhibited enhanced adaptability to these products, which were generated from ZGF photocatalytic pre-treatment of NFX. Key functional categories, including catalytic activity, oxidoreductase activity, and cytochrome P450 drug metabolism were significantly upregulated. This study indicates that the ZGF/microalgae system simultaneously achieves efficient pollutant degradation and maintains high metabolic potential as revealed by transcriptomic profiling, providing crucial insights for developing stable and sustainable bioremediation technologies.

Biogenic synthesis of ferrous(III) oxide and Fe3O4/SiO2 using Chlorella sp. and its adsorption properties of water contaminated with copper(II) ions

Shireen Ibrahim Hamadamin,Sewgil Saaduldeen Anwer,Parween Mohsin Abdulkareem,Kwestan Hassan Sdiq

Response of Chlorella vulgaris to exposure to CuO NPs: Contributions of particulate and dissolved metal forms as modulated by tannic acid and pH

Yang Liu,Xia Wang,Bo Pan,Zhuo Wei,Jing Zhao,Hao Qiu,Christian E.W. Steinberg,Willie J.G.M. Peijnenburg,Martina G. Vijver

A suspension of copper oxide nanoparticles (CuO NPs) is a mixture of dissolved and particulate Cu, the relative proportions of which highly depend on the water chemistry. However, the relationship between different proportions of particulate and dissolved Cu and the overall toxicity of CuO NPs is still unknown. This study investigated the response of Chlorella vulgaris to CuO NPs at varying solution pH and at different tannic acid (TA) additions, with a focus on exploring whether and how dissolved and particulate Cu contribute to the overall toxicity of CuO NPs. The results of the exposure experiments demonstrated the involvement of both dissolved and particulate Cu in inducing toxicity of CuO NPs, and the inhibition of CuO NPs on cell density of Chlorella vulgaris was found to be significantly ( p  < 0.05) alleviated with increased levels of TA and pH (< 8). Using the independent action model, the contribution to toxicity of particulate Cu was found to be enhanced with increasing pH values and TA concentrations. The toxic unit indicator better ( R 2 = 0.86, p  < 0.001) explained impacts of CuO NPs on micro-algae cells than commonly used mass concentrations ( R 2 = 0.27–0.77, p  < 0.05) across different levels of pH and TA. Overall, our study provides an additivity-based method to improve the accuracy of toxicity prediction through including contributions to toxicity of both dissolved and particulate Cu and through eliminating the uneven distribution of data due to large variations in total Cu, particulate Cu, dissolved Cu, Cu 2+ activities, Cu-TA complexes and other Cu-complexes concentrations with varying water chemistry conditions.

Chlorella pyrenoidosa improves meat quality and flavor precursors of fattening lambs by regulating jejunal microbiota and muscle metabolism via the gut–muscle axis

Jiantao Zhao,Shu Li,Jinglei Wang,Weibing Zeng,Yayin Qi,Xiaolin Xu,Jianhua Fan,Cheng Chen,Wenju Zhang

This study elucidates the mechanism by which Chlorella pyrenoidosa enhances meat quality in finishing lambs via modulation of the jejunal microbiota and muscle metabolism. In a 60-day trial, 32 lambs were fed diets supplemented with 0%, 1%, 3%, or 5% C. pyrenoidosa . C. pyrenoidosa supplementation significantly improved meat color, elevated amino acid (AA) and polyunsaturated fatty acid (PUFA) levels, and reduced saturated fatty acid content in the Longissimus dorsi muscle. 16S rRNA gene sequencing identified an enrichment of specific jejunal microbes, including Bifidobacterium and Mogibacterium . Integrated microbiota-metabolome analysis indicated that C. pyrenoidosa modulated the D-amino acid metabolism pathway. Transcriptome analysis revealed the upregulation of key genes involved in fatty acid β-oxidation (carnitine palmitoyltransferase 1B, CPT1B ) and amino acid synthesis (glutamic-oxaloacetic transaminase 1, GOT1 ). In conclusion, C. pyrenoidosa enhances lamb meat quality by remodeling the jejunal microbiota and concurrently promoting both fatty acid β-oxidation and AA synthesis in muscle.

Investigation of the Migration Patterns for Nanoplastics With Different Sizes in Chlorella vulgaris and Their Effects on Heavy Metal Adsorption by the Microalgae

Yan Liu,Zhongyuan Wei,Qiao Wang,Xin Liu,Zhiyong Gong

Polystyrene nanoparticles (PS-NPs) size determines their adsorption by Chlorella vulgaris , which induces size-dependent changes in cell membrane properties, and these two effects synergistically regulate the alga's heavy metal adsorption capacity via the carrier effect of PS-NPs. By using laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nanoparticle tracking analysis (NTA), it assessed resultant changes in cellular membrane parameters and explored the influence of different-sized PS-NPs, acting as carriers, on algal adsorption of heavy metals. C. vulgaris achieved adsorption for three nanoparticle size fractions within 1 h. Following uptake by C. vulgaris , PS-NPs of different sizes exhibited distinct intracellular and extracellular distribution patterns. Smaller NPs entered cells, while larger ones remained surface-bound. Following adsorption of polystyrene nanoparticles of varying sizes, C. vulgaris exhibited alterations in cell membrane parameters, including increased hydrophobicity and decreased permeability. These changes were size-dependent. Notably, PS-NPs of different sizes demonstrated distinct capacities for adsorbing Hg 2+ , Cd 2+ , and Pb 2+ . PS-NPs were found to influence the adsorption of these heavy metals by C. vulgaris through altering cell membrane parameters and acting as carriers for the metal ions, thereby modifying the alga's equilibrium adsorption capacity.

Size-dependent aquatic toxicity of TiO2 and ZnO nanoparticles in Chlorella vulgaris: antagonistic interactions at high concentrations vs. synergistic effects at environmental levels

Minghua Liu,Ran Bi,Guang Wang,Donghui Han,Zhuang Wang,Juan Wu,Ping Ding,Ye Wu,Shou Yang,Qi Yu

The widespread use of titanium dioxide (TiO 2 NPs) and zinc oxide nanoparticles (ZnONPs) in sunscreens necessitates a deeper understanding of their size-dependent aquatic toxicity and interaction mechanisms. This study systematically evaluates the individual and combined effects of TiO 2 NPs (5-10, 40, 100   nm) and ZnONPs (30, 50, 90   nm) on Chlorella vulgaris , integrating physicochemical behavior, oxidative stress responses, and interaction effects. ZnONPs exhibited 5.0–12.6 times higher toxicity than TiO 2 NPs, with EC 50 values of 55.9–77.0   mg   L -1 for ZnONPs versus 385.8–704.3   mg   L -1 for TiO 2 NPs. Smaller TiO 2 NPs (5–10   nm) showed greater toxicity ( EC 50 = 385.8   mg   L -1 ) than larger ones (704.3   mg   L -1 for 100   nm), while larger ZnONPs (90   nm) released 40% more Zn 2+ ions than smaller ones (20% for 30   nm). Joint toxicity presented was antagonistic at high concentrations but synergistic at low ( EC 5 ) and environmental levels ( p < 0.05). Small-sized mixtures (10   nm TiO 2 NPs + 30   nm ZnONPs) and large-sized mixtures (100   nm TiO 2 NPs + 90   nm ZnONPs) elevated malondialdehyde (MDA) levels by 1.8-fold compared to individual treatments. After 48   h depuration, reductions in MDA and superoxide dismutase (SOD) activities suggested cellular self-recovery, except the medium-sized mixtures remained persistent reactive oxygen species (ROS) depletion and impaired enzymatic recovery at specific concentration levels. These results provide new insights into nanoparticle toxicity mechanisms, underscoring that synergistic effects at environmentally realistic concentrations (ng L -1 to μg L -1 ) may pose unanticipated ecological risks to primary producers and disrupt aquatic food webs.

Less toxic combined microplastics exposure towards attached Chlorella sorokiniana in the presence of sulfamethoxazole while massive microalgal nitrous oxide emission under multiple stresses

Ying Zhang,Ming-Zhi Shen,Jian-Xia Wang,Jing-Han Wang,Zhan-You Chi

Microalgae-based wastewater treatment could realize simultaneous nutrients recovery and CO 2 sequestration. However, impacts of environmental microplastics (MPs) and antibiotic co-exposure on microalgal growth, nutrients removal, intracellular nitric oxide (NO) accumulation and subsequent nitrous oxide (N 2 O) emission are unclarified, which could greatly offset the CO 2 sequestration benefit. To reveal the potential impacts of environmental concentrations of MPs and antibiotic co-exposure on microalgal greenhouse gas mitigation, this study investigated the effects of representative MPs (PE, PVC, PA), antibiotic sulfamethoxazole (SMX), and nitrite (NO 2 - -N) in various combinations on attached Chlorella sorokiniana growth, nutrients removal, anti-oxidative responses, and N 2 O emission originated from intracellular NO build-up. Microalgal biofilm growth was more inhibited under 10 μg/L MPs than 100 μg/L SMX, and MPs+SMX co-exposure displayed toxicity antagonism while MPs+MPs co-exposure caused toxicity synergism (up to 66 % growth inhibition). Extracellular polysaccharides content correlated well with microalgal biofilm density under various stresses, while SMX involved stresses displayed chlorophyll a content reduction. Microalgal assimilation and MPs adsorption contributed to nutrients removal, and phosphorus removal displayed less variance among different stresses (residual phosphorus <0.5 mg/L) than nitrogen. Intracellular NO conversion to N 2 O almost doubled during the co-exposure processes, and N 2 O emission under NO 2 - -N + PE+PVC co-exposure could offset the contribution of microalgal CO 2 sequestration by as high as 176.2 %. Results of this study appealed for urgent concern regarding environmental MPs and antibiotic co-exposure on primary producers’ growth characteristics and their greenhouse gas mitigation properties.

Performance evaluation of different chitosan-clay composite materials for efficient harvesting of Chlorella vulgaris and impacts on downstream bioproduct processing and water reusability

Zhihong Yin,Shuangxi Li,Dan Hu,Zhuo Li,Ruoyu Chu,Chenchen Liu,Xinzhu Li,Jiangjun Hu,Liandong Zhu

As an environmentally friendly bioflocculant, chitosan has a great application potential in the field of microalgae harvesting due to its biocompatibility. In this work, three different inorganic clay minerals (kaolin, montmorillonite, and diatomite) were selected to prepare chitosan-clay composite materials (CTS/KAL, CTS/MML and CTS/DTE) as flocculants to harvest microalgae cells. The harvesting capacities of CTS/KAL, CTS/MML and CTS/DTE were accordingly 97.37%, 97.81% and 98.34% for microalgae cells under the dosage of 60 mg/L, microalgae concentration of 0.923 g/L, settling time of 30 min and pH of 10. CTS/DTE showed excellent harvesting performance for microalgae cells, mainly due to the enhancement of charge neutralization, sweeping and bridging effects. Based on the phenomenological theory, the second-order polynomial model was used to analyze the influences of different external factors on the microalgae harvesting efficiency. A reasonable performance relationship between CTS-clays for harvesting of microalgae cells and external factors was established. The analysis of carbohydrates, proteins, and fatty acids of microalgae biomass collected by CTS/KAL, CTS/MML, CTS/DTE and centrifugation showed that the harvesting of CTS-clay did not influence the properties of biomass. The experimental results of water resource recycling and re-cultivation after microalgae harvesting by CTS/KAL, CTS/MML and CTS/DTE exhibited that the growth rates of 50% circulating medium + 50% fresh BG11 culture medium were accordingly 2.512, 2.466 and 2.572 times higher than those of 100% circulating medium. It is concluded that chitosan-clay composite materials are efficient and environmentally friendly flocculants with a great applicable potential in microalgae harvesting.

Characterisation of volatile organic compounds in Chlorella pyrenoidosa cultured with different selenium concentrations using E-nose, GC–IMS, GC–MS, and machine learning algorithms

Siyan Liu,Heyu Pan,Yanchao Mao,Feifei Wang,Na Zhang,Shuyi Li,Zhenzhou Zhu

Chlorella pyrenoidosa is a promising plant-based protein source , whereas the volatile off-flavours derived from lipid oxidation substantially limit consumer acceptance. Selenium (Se) is recognised as a beneficial trace element that can improve flavour characteristics in plants by enhancing antioxidant capacity. This study investigated the effects of Se supplementation (0–2 mg/L) on the volatile profile of C. pyrenoidosa and explored the underlying mechanisms. E-nose analysis revealed significant differences in flavour profile among the treatments. GC–IMS and GC–MS identified 25 and 28 volatile organic compounds (VOCs), respectively. Fifteen key aroma compounds were screened by orthogonal partial least squares discriminant analysis (OPLS–DA), random forest (RF) modelling, and odour activity value (OAV) and relative OAV (ROAV) calculations. Notably, 0.50 mg/L Se was identified as the optimal enrichment concentration, as it improved overall flavour quality by reducing aldehyde accumulation, particularly hexanal. This improvement was attributed to Se-mediated reductions in lipid content and enhanced antioxidant capacity, as evidenced by increased glutathione peroxidase (GPx) activity, reduced reactive oxygen species (ROS) levels, and alleviated lipid peroxidation, alongside decreased lipoxygenase (LOX) and hydroperoxide lyase (HPL) activities by 60.08% and 37.31% respectively, thereby inhibiting the formation of off-flavour VOCs. Overall, this study provides the first evidence that Se modulates the flavour profile of C. pyrenoidosa and preliminarily elucidates the mechanism by which appropriate Se supplementation improves flavour quality through reshaping biochemical composition, maintaining redox homeostasis, and regulating key enzymes involved in aldehyde biosynthesis. These findings offer a theoretical foundation for developing novel functional microalgal-based foods.

Continuous Liquid–Liquid Extraction of High-Purity Lutein from Chlorella vulgaris via Centrifugal Partition Chromatography: Utilizing Limonene as Renewable Solvent for Microalgae Biomass Valorization

Weiheng Kong,Xianjiang Lin,Jing Ye,Yanbin Lu

In this study, an efficient and eco-friendly method was developed for continuous liquid–liquid extraction of lutein from microalgaeChlorella vulgaris. By employing a limonene-based biphasic liquid system, high-purity lutein was successfully obtained from the crude extract in a single run via centrifugal partition chromatography (CPC). Evaluation and optimization results demonstrated that limonene could effectively serve as a replacement forn-hexane as the solvent system for lutein extraction, exhibiting natural renewability and minimal environmental impact. Furthermore, the elution–extrusion operation mode was employed to fully exploit the liquid nature of the stationary phase in the extraction process, allowing for continuous sampling and separation without interruption. This proposed protocol offers a sustainable and environmentally friendly alternative for extracting valuable ingredients from microalgae biomass, demonstrating its potential as a scalable solution for producing lutein-enriched ingredients applicable to functional foods and nutraceuticals.

Probing the interaction induced conformation transitions in acid phosphatase with cobalt ferrite nanoparticles: Relation to inhibition and bio-activity of Chlorella vulgaris acid phosphatase

Farooq Ahmad,Xing Zhou,Hongzhou Yao,Ying Zhou,Chao Xu

The present study explored the interaction and kinetics of cobalt ferrite nanoparticles (NPs) with acid phosphatase (ACP) by utilizing diverse range of spectroscopic techniques. The results corroborate, the CoFe 2 O 4 NPs cause fluorescence quenching in ACP by static quenching mechanism. The negative values of van’t Hoff thermodynamic expressions (Δ H   =   −0.3293   J   mol −1 K −1 and Δ G   =   −3.960   kJ   mol −1 K −1 ) corroborate the spontaneity and exothermic nature of static quenching. The positive value of ΔS (13.2893   J   mol −1 K −1 ) corroborate that major contributors of higher and stronger binding affinity among CoFe 2 O 4 NPs with ACP were electrostatic. In addition, FTIR, UV-CD, UV–vis spectroscopy and three dimensional fluorescence (3D) techniques confirmed that CoFe 2 O 4 NPs binding induces microenvironment perturbations leading to secondary and tertiary conformation changes in ACP to a great extent. Furthermore, synchronous fluorescence spectroscopy (SFS) affirmed the comparatively significant changes in microenvironment around tryptophan (Trp) residue by CoFe 2 O 4 NPs. The effect of CoFe 2 O 4 NPs on the activation kinetics of ACP was further examined in Chlorella vulgaris . Apparent Michaelis constant (Km) values of 0.57 and 26.5   mM with activation energy values of 0.538 and 3.428   kJ   mol −1 were determined without and with 200   μM CoFe 2 O 4 NPs. Apparent Vmax value of −7   Umml −1 corroborate that enzyme active sites were completely captured by the NPs leaving no space for the substrate. The results confirmed that CoFe 2 O 4 NPs ceased the activity by unfolding of ACP enzyme. This suggests CoFe 2 O 4 NPs perturbed the enzyme activity by transitions in conformation and hence the metabolic activity of ACP. This study provides the pavement for novel and simple approach of using sensitive biomarkers for sensing NPs in environment.

Electron transfer via CoO coupled to NPC derived from N, P-rich Chlorella pyrenoidosa enhanced radical-nonradical process in catalytic ozonation for efficient ibuprofen removal

Xingyue Wei,Hanmin Zhang,Mengbo Cao

In this study, a series of Co-doped NPC biochar (nCo-NPC) was prepared by one-step pyrolysis of N and P-rich Chlorella pyrenoidosa (CP) waste mixed with cobalt nitrate for heterogeneous catalytic ozonation (HCO) degradation of ibuprofen (IBU). Compared to the HCO process using CoOx or NPC catalysts, the 2Co-NPC catalyst showed superior performance in the degradation of IBU due to the synergistic effect between the CoOx and NPC. The 2Co-NPC catalyst exhibited high stability after five trials, with the removal efficiency decreasing from 99.9 % to 85.4 %. Moreover, hydroxyl radicals ( OH) and adsorbed atomic oxygen (*O) were identified as the main active species in 2Co-NPC HCO process. The coupling of NPC and CoOx formed electron-rich Co(II) center and electron-deficient NPC center. The electron-rich Co(II) center can direct decomposition of adsorbed ozone into *O and further convert to OH. The electron-deficient NPC center gained electrons from organic pollutants, C N, C O, and P groups through C O Co and C N Co bonds, stimulating the π-cation reaction to transfer to the Co(II) center, thus accelerating the cycling between Co(II) and Co(III). Additionally, the deprotonation of surface hydroxyl groups may also serve as a potential active site for the decomposition of ozone into OH. This study used biomass CP as a precursor coupled with cobalt salt, revealing electron transfer pathways and providing new insights for the future developing of low-cost, efficient, and stable ozone catalysts.