Assessing the ecological impact of pesticides/herbicides on algal communities: A comprehensive review.

The escalating use of pesticides in agriculture for enhanced crop productivity threatens aquatic ecosystems, jeopardizing environmental integrity and human well-being. Pesticides infiltrate water bodies through runoff, chemical spills, and leachate, adversely affecting algae, vital primary producers in marine ecosystems. The repercussions cascade through higher trophic levels, underscoring the need for a comprehensive understanding of the interplay between pesticides, algae, and the broader ecosystem. Algae, susceptible to pesticides via spillage, runoff, and drift, experience disruptions in community structure and function, with certain species metabolizing and bioaccumulating these contaminants. The toxicological mechanisms vary based on the specific pesticide and algal species involved, particularly evident in herbicides' interference with photosynthetic activity in algae. Despite advancements, gaps persist in comprehending the precise toxic effects and mechanisms affecting algae and non-target species. This review consolidates information on the exposure and toxicity of diverse pesticides and herbicides to aquatic algae, elucidating underlying mechanisms. An emphasis is placed on the complex interactions between pesticides/herbicides, nutrient content, and their toxic effects on algae and microbial species. The variability in the harmful impact of a single pesticide across different algae species underscores the necessity for further research. A holistic approach considering these interactions is imperative to enhance predictions of pesticide effects in marine ecosystems. Continued research in this realm is crucial for a nuanced understanding of the repercussions of pesticides and herbicides on aquatic ecosystems, mainly algae.

Heterogeneous photocatalytic degradation of antiviral drug didanosine mediated by rose bengal and TiO2 nanoparticles.

There is a great concern among the researcher to remove the problem of the persistent organic pollutants in wastewater. Pharmaceutical agrochemical and personal care products are generally considered Persistent organic pollutants. Therefore, it is a matter of concern to develop new techniques how to remove these pollutants safely at low cost. This study mainly focuses on the commonly used antiviral drug didanosine and one most commonly used dye rose bengal. In this study, an organic dye rose bengal and TiO2 nanoparticles have been used in combination with UV light to achieve the photodegradation of selected pharmaceutical products and the dye was also degraded by using TiO2 Nanoparticles. The formation of three oxidation products was detected by using a very popular separation technique thin layer and column chromatography. The isolated photoproduct was characterized by using advanced characterization techniques like FTIR (Fourier transform infrared spectroscopy), UV Spectroscopy, and Proton and 13C NMR (Nuclear Magnetic Resonance spectroscopy). The role of singlet oxygen as an active species in this reaction was confirmed by using D2O as a reaction medium. The role of singlet oxygen in this photochemical reaction was also established by the addition of sodium azide. The TiO2 nanophotocatalyst efficiently degrade the didanosine and rose bengal in the presence of the UV light. In the TiO2-induced photocatalytic degradation of didanosine and dyes, the hydroxyl and superoxide radical anion play a prominent role. The finding of this manuscript is very useful to develop an efficient low-cost method for the treatment of wastewater contaminated by antiviral drugs, similar pharmaceutical products and dyes. This study was also very helpful to establish a plausible mechanism behind the phototoxicity of the didanosine.

Nanotechnology-driven improvisation of red algae-derived carrageenan for industrial and bio-medical applications.

Algae biomass has been recognized as feedstock with diverse application including production of biofuel, biofertilizer, animal feed, wastewater treatment and bioremediation. In addition, algae species are a potential reservoir of metabolites and polymers with potential to be utilized for biomedicine, healthcare and industrial purposes. Carrageenan is one such medicinally and industrially significant polysaccharide which is extracted from red algae species (Kappaphycus alvarezii and Eucheuma denticulatum, among the common species). The extraction process of carrageenan is affected by different environmental factors and the source of biomass, which can vary and significantly impact the yield. Diverse applications of carrageenan include hydrogel beads, bio-composites, pharmacological properties, application in cosmetics, food and related industries. Carrageenan biological activities including antioxidant, anti-inflammatory, antimicrobial, and antitumor activities are significantly influenced by sulfation pattern, yield percentage and molecular weight. In addition to natural biomedical potential of carrageenan, synergetic effect of carrageenan- nanocomposites exhibit potential for further improvisation of biomedical applications. Nanotechnology driven bio-composites of carrageenan remarkably improve the quality of films, food packaging, and drug delivery systems. Such nano bio-composites exhibit enhanced stability, biodegradability, and biocompatibility, making them suitable alternatives for drug delivery, wound-healing, and tissue engineering applications. The present work is a comprehensive study to analyze biomedical and other applications of Carrageenan along with underlying mechanism or mode of action along with synergetic application of nanotechnology.

Development of yeast and microalgae consortium biofilm growth system for biofuel production.

Background: The current study aimed to develop a laboratory-scale biofilm photobioreactor system for biofuel production. Scope & Approach: During the investigation, Jute was discovered to be the best, cheap, hairy, open-pored supporting material for biofilm formation. Microalgae & yeast consortium was used in this study for biofilm formation. Conclusion: The study identified microalgae and yeast consortium as a promising choice and ideal partners for biofilm formation with the highest biomass yield (47.63 ± 0.93 g/m2), biomass productivity (4.39 ± 0.29 to 7.77 ± 0.05 g/m2/day) and lipid content (36%) over 28 days cultivation period, resulting in a more sustainable and environmentally benign fuel that could become a reality in the near future.

Bio-oil and biochar production from Ageratum conyzoides using triple-stage hydrothermal liquefaction and utilization of biochar in removal of multiple heavy metals from water.

Production of low-cost biomass and its utilization for producing cost effective and eco-friendly bioenergy as well as for removing heavy metals from water can be explored as an approach to meet the sustainable development goals. In light of the above-mentioned study, hydrothermal liquefaction (HTL) of Billy goat weed (BGW; Ageratum conyzoides) was carried out to produce bio-oil. In addition, the residual biochar from the HTL process was activated to obtain Act-BC and was further modified to produce MnO2-loaded biochar (Act-BC@MnO2-25%). The HTL of BGW was done at three different temperatures, i.e., 250 °C, 350 °C and 450 °C in a high-pressure batch reactor to maximize the bio-oil yield. Also, two different HTL methods i.e., single-stage HTL and triple-stage HTL of BGW were compared and discussed in detail. The bio-oil obtained via the triple-stage HTL was rich in carbon, hydrogen, and nitrogen. It also showed a higher heating value (HHV) and bio-oil yield (46%) than the single-stage. The residual biochar obtained at 450 °C (Act-BC) and MnO2 modified (Act-BC@MnO2-25%) were then tested to adsorb multiple heavy metal (i.e., Pb(II), Cd(II), Cu(II), and Ni(II)) from water. The kinetics data obtained from the adsorption experiment with Act-BC@MnO2-25% were well fitted to PSO kinetics model. The isotherm data were well aligned with the Langmuir model; the adsorption capacity of Act-BC@MnO2-25% was estimated to be 198.70 ± 11.40 mg g-1, 93.70 ± 6.60 mg g-1, 78.90 ± 7.20 mg g-1 and 30.50 ± 2.10 mg g-1 for Pb(II), Cd(II), Cu(II), and Ni(II), respectively. Furthermore, Act-BC@MnO2-25% remained active for metal ions absorption even after six consecutive uses. The result obtained from this study clearly demonstrates that the triple-stage HTL of BGW is a promising technology to achieve both remediation of metal-contaminated water and production of bioenergy.

A phyco-nanobionics biohybrid system for increased carotenoid accumulation in C. sorokiniana UUIND6.

Recent advancements in "phyco-nanobionics" have sparked considerable interest in the ability of microalgae to synthesize high-value natural bioactive compounds such as carotenoid pigments, which have been highlighted as an emergent and vital bioactive compound from both industrial and scientific perspectives. Such bioactive compounds are often synthesized by either altering the biogenetic processes existing in living microorganisms or using synthetic techniques derived from petroleum-based chemical sources. A bio-hybrid light-driven cell factory system was established herein by using harmful macroalgal bloom extract (HMBE) and efficient light-harvesting silver nanoparticles (AgNPs) to synthesize HMBE-AgNPs and integrating the synthesized HMBE-AgNPs in various concentrations (1, 2.5, 5 and 10 ppm) into the microalgae C. sorokiniana UUIND6 to improve the overall solar-to-chemical conversion efficiency in carotenoid pigment synthesis in microalgae. The current study findings found high biocompatibility of 5 ppm HMBE-AgNP concentration that can serve as a built-in photo-sensitizer and significantly improve ROS levels in microalgae (6.75 ± 0.25 µmol H2O2 g-1), thus elevating total photosynthesis resulting in a two-fold increase in carotenoids (457.5 ± 2.5 µg mL-1) over the native microalgae without compromising biomass yield. NMR spectroscopy was additionally applied to acquire a better understanding of pure carotenoids derived from microalgae, which indicated similar peaks in both spectra when compared to ß-carotene. Thus, this well-planned bio-hybrid system offers a potential option for the cost-effective and long-term supply of these natural carotenoid bio-products.

Multimodal Spatiotemporal Deep Learning Framework to Predict Response of Breast Cancer to Neoadjuvant Systemic Therapy.

Current approaches to breast cancer therapy include neoadjuvant systemic therapy (NST). The efficacy of NST is measured by pathologic complete response (pCR). A patient who attains pCR has significantly enhanced disease-free survival progress. The accurate prediction of pCR in response to a given treatment regimen could increase the likelihood of achieving pCR and prevent toxicities caused by treatments that are not effective. Th early prediction of response to NST can increase the likelihood of survival and help with decisions regarding breast-conserving surgery. An automated NST prediction framework that is able to precisely predict which patient undergoing NST will achieve a pathological complete response (pCR) at an early stage of treatment is needed. Here, we propose an end-to-end efficient multimodal spatiotemporal deep learning framework (deep-NST) framework to predict the outcome of NST prior or at an early stage of treatment. The deep-NST model incorporates imaging data captured at different timestamps of NST regimens, a tumor's molecular data, and a patient's demographic data. The efficacy of the proposed work is validated on the publicly available ISPY-1 dataset, in terms of accuracy, area under the curve (AUC), and computational complexity. In addition, seven ablation experiments were carried out to evaluate the impact of each design module in the proposed work. The experimental results show that the proposed framework performs significantly better than other recent methods.

Chitosan cross-linked ß-cyclodextrin polymeric adsorbent for the removal of perfluorobutanesulfonate from aqueous solution: adsorption kinetics, isotherm, and mechanism.

The existence of per- and polyfluoroalkyl substances (PFASs) in water is of serious interest due to their toxic, bioaccumulative, and persistent nature, and adsorption is an effective approach for the PFASs removal. In the present study, we developed a polymeric adsorbent by cross-linking chitosan and ß-cyclodextrin using glutaraldehyde (Chi-Glu-ß-CD) and evaluated its removal performance for perfluorobutanesulfonate (PFBS) from water. The results indicate that the performance was highly affected by solution pH; under a more acidic condition (e.g., pH 2.0), a higher removal efficiency was detected, and faster adsorption kinetics was observed with the rate constant (k2) of 0.001 ± 3×10-4 g mg-1 min-1. Adsorption isotherm data agreed to the Sips model with a maximum heterogeneous adsorption capacity of 135.70 ± 25.70 mg g-1, probably due to protonated amine (NH+) and electron-deficient ß-CD cavities. The adsorption mechanism was confirmed using energy dispersive X-ray and Fourier transform infrared (FTIR) spectroscopy, showing the role of electrostatic attractions between the protonated amine and the negatively charged PFBS molecule (especially, with sulfonate side (N-H--O-S)) and host-guest inclusion formations with ß-CD cavity in adsorption. Additionally, the synthesized adsorbent was recovered using methanol without any significant decline in adsorption efficiency even after four continuous adsorption/desorption cycles. All these findings suggested that the Chi-Glu-ß-CD composite could be a promising adsorbent in the removal of PFBS from water.

Simultaneous capturing of mixed contaminants from wastewater using novel one-pot chitosan functionalized with EDTA and graphene oxide adsorbent.

The emergence of inorganic and organic contaminants has raised great concerns owing to their adverse impact on human health and ecological security. Herein, first time one-pot process was applied for chitosan (CS) functionalization using graphene oxide (GO) and ethylenediaminetetraacetic acid (EDTA) for simultaneous capturing of toxic inorganic (lead (Pb2+) and cadmium (Cd2+)) and organic (ciprofloxacin (CIP) and sildenafil (SDF)) contaminants from wastewater. In this approach, we believe that CS would work as a backbone, GO would capture both inorganic and organic contaminants via electrostatic interactions, while EDTA would make complexation with heavy metals. Various parameters including pH, reaction time, concentration, reusability etc. were evaluated to achieve the best experimental result in monocomponent system. The prepared adsorbent displayed an excellent monolayer adsorption capacity of 351.20 and 264.10 mg g-1 for Pb2+ and Cd2+, respectively, while a heterogeneous sorption capacity of 75.40 and 40.90 mg g-1 for CIP and SDF, respectively. The kinetics data fitted well to Pseudo-second order (PSO) kinetics model for both types of contaminants and gave faster interaction towards metal ions (higher k2) than organic contaminants. Experimental results showed excellent adsorption efficiencies at environmental levels in the capturing of both inorganic and organic contaminants at the same time from polluted water. The capturing mechanism of both types of contaminants was explained by elemental mapping, EDS, and FT-IR spectra. Overall, easy synthesis, excellent capturing capacity, and reusability imply that the prepared adsorbent has a sufficient potential for the treatment of co-existing toxic contaminants in water.

Natural protein-based electrospun nanofibers for advanced healthcare applications: progress and challenges.

Electrospinning is an electrostatic fiber fabrication technique that operates by the application of a strong electric field on polymer solution or melts. It is used to fabricate fibers whose size lies in the range of few microns to the nanometer range. Historic development of electrospinning has evinced attention due to its outstanding attributes such as small diameter, excellent pore inter-connectivity, high porosity, and high surface-to-volume ratio. This review aims to highlight the theory behind electrospinning and the machine setup with a detailed discussion about the processing parameters. It discusses the latest innovations in natural protein-based electrospun nanofibers for health care applications. Various plant- and animal-based proteins have been discussed with detailed sample preparation and corresponding processing parameters. The usage of these electrospun nanofibers in regenerative medicine and drug delivery has also been discussed. Some technical innovations in electrospinning techniques such as emulsion electrospinning and coaxial electrospinning have been highlighted. Coaxial electrospun core-shell nanofibers have the potential to be utilized as an advanced nano-architecture for sustained release targeted delivery as well as for regenerative medicine. Healthcare applications of nanofibers formed via emulsion and coaxial electrospinning have been discussed briefly. Electrospun nanofibers have still much scope for commercialization on large scale. Some of the available wound-dressing materials have been discussed in brief.

Multifunctional ß-Cyclodextrin-EDTA-Chitosan polymer adsorbent synthesis for simultaneous removal of heavy metals and organic dyes from wastewater.

Heavy metals and organic dyes are the major source of water pollution. Herein, a trifunctional ß-cyclodextrin-ethylenediaminetetraacetic acid-chitosan (ß-CD-EDTA-CS) polymer was synthesized using an easy and simple chemical route by the reaction of activated ß-CD with CS through EDTA as a cross-linker (amidation reaction) for the removal of inorganic and organic pollutants from aqueous solution under different parameters such as pH, time effect, initial concentration, reusability, etc. The synthesized adsorbent was characterized using powder X-ray diffraction, Fourier transform infrared spectroscopy, field scanning electron microscopy, energy dispersive spectroscopy, Brunauer-Emmett-Teller (BET), thermogravimetric analyzer techniques to investigate their structural, functional, morphological, elemental compositions, surface area and thermal properties, respectively. Two types of heavy metals, i.e., mercury (Hg2+) and cadmium (Cd2+), and three organic dyes, i.e., methylene blue (MB), crystal violet (CV) and safranin O (SO) were chosen as inorganic and organic pollutants, respectively, to study the adsorption capacity of ß-CD-EDTA-CS in aqueous solution. The ß-CD-EDTA-CS shows monolayer adsorption capacity 346.30 ± 14.0 and 202.90 ± 13.90 mg g-1 for Hg2+ and Cd2+, respectively, and a heterogeneous adsorption capacity 107.20 ± 5.70, 77.40 ± 5.30 and 55.30 ± 3.60 mg g-1 for MB, CV and SO, respectively. Kinetics results followed pseudo-second order (PSO) kinetics behavior for both metal ions and dyes, and higher rate constants values (0.00161-0.00368 g mg-1 min-1) for dyes confirmed the cavitation of organic dyes (physisorption). In addition, we have also demonstrated the performance of ß-CD-EDTA-CS for the of four heavy metals Hg2+, Cd2+, Ni2+, and Cu2+ and three dyes MB, CV, and SO in secondary treated wastewater. Findings of this study indicate that ß-CD-EDTA-CS simple and essay to synthesize and can be use in wastewater treatment.

AutoMER: Spatiotemporal Neural Architecture Search for Microexpression Recognition.

Facial microexpressions offer useful insights into subtle human emotions. This unpremeditated emotional leakage exhibits the true emotions of a person. However, the minute temporal changes in the video sequences are very difficult to model for accurate classification. In this article, we propose a novel spatiotemporal architecture search algorithm, AutoMER for microexpression recognition (MER). Our main contribution is a new parallelogram design-based search space for efficient architecture search. We introduce a spatiotemporal feature module named 3-D singleton convolution for cell-level analysis. Furthermore, we present four such candidate operators and two 3-D dilated convolution operators to encode the raw video sequences in an end-to-end manner. To the best of our knowledge, this is the first attempt to discover 3-D convolutional neural network (CNN) architectures with a network-level search for MER. The searched models using the proposed AutoMER algorithm are evaluated over five microexpression data sets: CASME-I, SMIC, CASME-II, CAS(ME) ∧2 , and SAMM. The proposed generated models quantitatively outperform the existing state-of-the-art approaches. The AutoMER is further validated with different configurations, such as downsampling rate factor, multiscale singleton 3-D convolution, parallelogram, and multiscale kernels. Overall, five ablation experiments were conducted to analyze the operational insights of the proposed AutoMER.

Synthesis of EDTA-functionalized graphene oxide-chitosan nanocomposite for simultaneous removal of inorganic and organic pollutants from complex wastewater.

Discharging of inorganic and organic pollutants creates a serious threat to the human health and the environment. In the current work, we have synthesized Ethylenediaminetetraacetic acid (EDTA) functionalized graphene oxide-chitosan nanocomposite (GO-EDTA-CS) for simultaneous removal of inorganic (i.e., mercury (Hg(II) and copper (Cu(II)) and organic pollutants (i.e., methylene blue (MB) and crystal violet (CV)) from wastewater via adsorption process. The structural, functional, morphological, elemental compositions, surface area and thermal properties of the synthesized nanocomposite were identified using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET), and thermogravimetric analyzer (TGA), respectively. Different batch adsorption experiments such as pH effect, contact time, initial pollutants concentration, reusability etc. were studied in monocomponent system to optimize the results. The adsorption process apparently followed pseudo-second-order (PSO) kinetics for both pollutants, however the adsorption kinetics was also explained by the intra-particle diffusion model. The isotherm data for both metals ions and dyes were well fit by the Langmuir isotherm model. The maximum adsorption capacities of the adsorbent were determined 324 ± 3.30 130 ± 2.80, 141 ± 6.60, and 121 ± 3.50 mg g-1 for Hg(II), Cu(II), MB, and CV, respectively. The excellent adsorption capacity was attributed to the availability of various active functional groups (e.g., -COOH, -OH, -NH2, etc.) on the adsorbent. The EDS, elemental mapping and FTIR analysis performed before and after the adsorption of heavy metals and dyes by GO-EDTA-CS confirmed the simultaneous adsorption of the pollutants. Moreover, GO-EDTA-CS could maintain its adsorption capacity for both inorganic and organic pollutants even after seven cycles of adsorption-desorption, indicating itself a promising adsorbent for practical wastewater treatment containing both inorganic and organic toxic pollutants.

Simultaneous Removal of Heavy Metals and Ciprofloxacin Micropollutants from Wastewater Using Ethylenediaminetetraacetic Acid-Functionalized ß-Cyclodextrin-Chitosan Adsorbent.

The current study pertains to the synthesis of an EDTA-functionalized ß-cyclodextrin-chitosan (ß-CD-CS-EDTA) composite via a two-step process for the adsorptive removal of toxic heavy metallic ions (i.e., Pb(II), Cu(II), and Ni(II)) and antibiotic micropollutant, i.e., ciprofloxacin (CIP), from water. Different batch adsorption experiments such as pH, reaction time and initial pollutant concentration effects were carried out to identify the adsorption condition to attain the maximum removal efficiency. Kinetics results fit well with the pseudo-second order (PSO) kinetics model for both inorganic and organic pollutants. However, adsorption of heavy metal ions to the adsorbent was faster than that of CIP. Isotherms results showed excellent monolayer adsorption capacities of 330.90, 161, and 118.90 mg g-1 for Pb(II), Cu(II), and Ni(II), respectively, with a heterogeneous adsorption capacity of 25.40 mg g-1 for CIP. The adsorption mechanism was investigated using energy dispersive X-ray (EDX), elemental mapping, and Fourier transform infrared (FTIR) techniques. More significantly, the synthesized adsorbent gave good removal efficiencies when it was applied to simultaneously adsorb metal ions and CIP from real wastewater. Furthermore, excellent reusability could be obtained, making it a viable alternative to remove the inorganic and organic micropollutants for wastewater treatment.

Graphitic bio-char and bio-oil synthesis via hydrothermal carbonization-co-liquefaction of microalgae biomass (oiled/de-oiled) and multiple heavy metals remediations.

Thermochemical transformation of microalgae biomass into graphitic bio-chars entices as proficient bio-adsorbents for heavy metal contaminants. This study explores the synergistic impact of Chlorella sorokiniana on biomass generation and wastewater remediation in high rate algae pond (HRAP). Biomass produced was applied for hydrothermal carbonization-co-liquefaction (HTCL). The structural and morphological characteristics of HTCL products (i.e. bio-chars and bio-oils) have been systematically studied by XRD, Raman, FTIR, elemental analyzer, SEM, BET, and 1H NMR spectroscopy. The crystallite size of the graphite 2H indexing planes was to be 4.65 nm and 14.07 nm in the bio-chars of oiled biomass (MB-OB) and de-oiled biomass (MB-DOB), respectively. The increase in the ID/IG ratio of MB-DOB indicated the highly disordered graphitic structure due to the appearance of carbonyl, hydroxyl, and epoxy functionalities in the line of high C/N and low C/H ratio. Also, the multiple heavy metals remediation of MB-DOB revealed better efficiency as ~100% in 720 min. The kinetics analysis shows the correlation coefficient of pseudo-second-order is well fitted compared to the pseudo-first-order. The Langmuir adsorption model signifies the adsorption of heavy metal ions in a monolayer adsorption manner. The study proposes the microalgae bio-char potential for multiple heavy metals remediation alongside bio-oils.

LEARNet: Dynamic Imaging Network for Micro Expression Recognition.

Unlike prevalent facial expressions, micro expressions have subtle, involuntary muscle movements which are short-lived in nature. These minute muscle movements reflect true emotions of a person. Due to the short duration and low intensity, these micro-expressions are very difficult to perceive and interpret correctly. In this paper, we propose the dynamic representation of micro-expressions to preserve facial movement information of a video in a single frame. We also propose a Lateral Accretive Hybrid Network (LEARNet) to capture micro-level features of an expression in the facial region. The LEARNet refines the salient expression features in accretive manner by incorporating accretion layers (AL) in the network. The response of the AL holds the hybrid feature maps generated by prior laterally connected convolution layers. Moreover, LEARNet architecture incorporates the cross decoupled relationship between convolution layers which helps in preserving the tiny but influential facial muscle change information. The visual responses of the proposed LEARNet depict the effectiveness of the system by preserving both high- and micro-level edge features of facial expression. The effectiveness of the proposed LEARNet is evaluated on four benchmark datasets: CASME-I, CASME-II, CAS(ME)'2 and SMIC. The experimental results after investigation show a significant improvement of 4.03%, 1.90%, 1.79% and 2.82% as compared with ResNet on CASME-I, CASME-II, CAS(ME)'2 and SMIC datasets respectively.

Low-temperature catalyst based Hydrothermal liquefaction of harmful Macroalgal blooms, and aqueous phase nutrient recycling by microalgae.

The present study investigates the hydrothermal liquefaction (HTL) of harmful green macroalgal blooms at a temperature of 270 °C with, and without a catalyst with a holding time of 45 min. The effect of different catalysts on the HTL product yield was also studied. Two separation methods were used for recovering the biocrude oil yield from the solid phase. On comparision with other catalyst, Na2CO3 was found to produce higher yiled of bio-oil. The total bio-oil yield was 20.10% with Na2CO3, 18.74% with TiO2, 17.37% with CaO, and 14.6% without a catalyst. The aqueous phase was analyzed for TOC, COD, TN, and TP to determine the nutrient enrichment of water phase for microalgae cultivation. Growth of four microalgae strains viz., Chlorella Minutissima, Chlorella sorokiniana UUIND6, Chlorella singularis UUIND5 and Scenedesmus abundans in the aqueous phase were studied, and compared with a standard growth medium. The results indicate that harmful macroalgal blooms are a suitable feedstock for HTL, and its aqueous phase offers a promising nutrient source for microalgae.

Detoxification mechanism of organophosphorus pesticide via carboxylestrase pathway that triggers de novo TAG biosynthesis in oleaginous microalgae.

Organophosphorus compounds exhibit a wide range of toxicity to mammals. In this study the effect of malathion on the growth and biochemical parameters of microalgae was evaluated. Three microalgae (Micractinium pusillum UUIND2, Chlorella singulari UUIND5 and Chlorella sorokiniana UUIND6) were used in this study. Among the three algal strains tested, Chlorella sorokiniana UUIND6 was able to tolerate 100 ppm of malathion. The photosynthetic pigments, the protein, carbohydrate and lipid contents of microalgal cells were also analyzed. About 90% degradation was recorded in 25 ppm, 50 ppm and 70% was recorded in 100 ppm of malathion by Chlorella sorokiniana. A mechanism of degradation of malathion by Chlorella sorokiniana is proposed in this study. Activity of carboxylesterase was increased in algal cells cultivated in malathion containing medium which confirmed that malathion degraded into phosphate. Increased amount of Malondialdehye (MDA) indicate the development of free radicals under the stress of malathion which substantialy increase de novo TAG biosynthesis, while increased level of superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) suggested their association in scavenging of free radical.

Application of agar liquid-gel transition in cultivation and harvesting of microalgae for biodiesel production.

In order to increase microalgal biomass productivity efficient cultivation and harvesting methods are needed against the available traditional methods. The present study focuses on the same by harvesting microalgae using agar gel. Agar medium containing bold's basal medium (BBM) undergoes a thermoreversible gel transition. As compared to the traditional protocols, this gel is used to cultivate microalgae without even affecting the total productivity. To develop the gel for microalgae cultivation, agar was boiled in BBM. Then the agar was cooled to 35°C and microalgae culture was added to it. After seeding the microalgae the temperature of the agar was further decreased by 10°C to induce gelation. Instead of isolated cells microalgae were grown in clusters within the agar gel. Microalgal clusters gravimetrically settle at the bottom within 2h. In this method agar can be reused.

Removal of hexavalent chromium ions using CuO nanoparticles for water purification applications.

Copper(II) oxide nanoparticles were synthesized at low temperature using cold finger assisted magnetron sputtering technique and were applied as adsorbent for the rapid removal of noxious Cr(VI) ions from the solvent phase. The average size of CuO nanoparticles from TEM analysis was found to be 8nm in addition to this the BET surface area (84.327m(2)/g) was found to be significantly high in comparison to the previously CuO nanoparticles synthesized via green route. The synthesized CuO nanoparticles is crystalline in nature and exhibits monoclinic phase, which was confirmed using various analytical techniques such as SAED, XRD and Raman analysis. The impact of influential parameters including pH, adsorbent dose, contact time, stirring speed, initial Cr(VI) ions concentration, and temperature were optimized using batch adsorption method in order to obtain maximum removal of Cr(VI) ions. From the thermodynamic parameters, the positive value of enthalpy (ΔH) and negative value of Gibbs free energy (ΔG) indicate the endothermic and spontaneous nature of Cr(VI) ions adsorption, respectively. The adsorption kinetics data was well fitted and found to be in good agreement with the pseudo second order kinetic behaviour.