The concept of zero waste discharge has been gaining importance in recent years towards attaining a sustainable environment. Fruit processing industries generate millions of tons of byproducts like fruit peels and seeds, and their disposal poses an environmental threat. The concept of extracting value-added bioactive compounds from bio-waste is an excellent opportunity to mitigate environmental issues. To date, significant research has been carried out on the extraction of essential biomolecules, particularly polysaccharides from waste generated by fruit processing industries. In this review article, we aim to summarize the different extraction methodologies, characterization methods, and biomedical applications of polysaccharides extracted from seeds and peels of different fruit sources. The review also focuses on the general scheme of extraction of polysaccharides from fruit waste with special emphasis on various methods used in extraction. Also, the various types of polysaccharides obtained from fruit processing industrial wastes are explained in consonance with the important techniques related to the structural elucidation of polysaccharides obtained from seed and peel waste. The use of seed polysaccharides as pharmaceutical excipients and the application of peel polysaccharides possessing biological activities are also elaborated.
Two new azadirone-type limonoids, namely lasiocarpine A (1) and lasiocarpine B (2) were isolated from the fruit of Chisocheton lasiocarpus along with three known limonoids (3-5). UV, IR, one- and two- dimensional NMR, and mass spectrometry were used to determine the chemical structure of the isolated compounds. Furthermore, their cytotoxic activity against breast cancer cell line MCF-7 was evaluated using PrestoBlue reagent. From these compounds, lasiocarpine A (1) showed the strongest activity with an IC50 value of 43.38 μM.
In this study, a facile hydrothermal method was employed to prepare Me-doped Bi2Fe4O9 (Me = Zn, Cu, Co, and Mn) as peroxymonosulfate (PMS) activator for ciprofloxacin (CIP) degradation. The characteristics of the Me-doped bismuth ferrites were investigated using various characterization instruments including SEM, TEM, FTIR and porosimeter indicating that the Me-doped Bi2Fe4O9 with nanosheet-like square orthorhombic structure was successfully obtained. The catalytic activity of various Me-doped Bi2Fe4O9 was compared and the results indicated that the Cu-doped Bi2Fe4O9 at 0.08 wt.% (denoted as BFCuO-0.08) possessed the greatest catalytic activity (kapp = 0.085 min-1) over other Me-doped Bi2Fe4O9 under the same condition. The synergistic interaction between Cu, Fe and oxygen vacancies are the key factors which enhanced the performance of Me-doped Bi2Fe4O9. The effects of catalyst loading, PMS dosage, and pH on CIP degradation were also investigated indicating that the performance increased with increasing catalyst loading, PMS dosage, and pH. Meanwhile, the dominant reactive oxygen species was identified using the chemical scavengers with SO4•-, •OH, and 1O2 playing a major role in CIP degradation. The performance of BFCuO-0.08 deteriorated in real water matrix (tap water, river water and secondary effluent) due to the presence of various water matrix species. Nevertheless, the BFCuO-0.08 catalyst possessed remarkable stability and can be reused for at least four successive cycles with >70% of CIP degradation efficiency indicating that it is a promising catalyst for antibiotics removal.
The prevalence of lung diseases is increasing year by year and existing drug therapies only provide symptomatic relief rather than targeting the actual cause. Nucleic acids can be used as an alternative therapeutic approach owing to their potential to reform a homeostatic balance by upregulating protective genes or downregulating damaging genes. However, their inherent properties, such as poor stability, ineffective cellular uptake, negative charge and so on, hinder their clinical utility. Such limitations can be overcome by exploiting the functional chemistry of polymeric micelles (PMs) for site-specific delivery, transfection efficiency and improved stability. With this objective, the present work describes the advancements made in designing nucleic acid-based PMs for treating lung diseases followed by approaches requiring consideration for clinical applications.
In this study, the chemical substance flow of hydrogen fluoride (hydrofluoric acid, HF) in domestic chemical industries in 2014 was analyzed in order to provide a basic material and information for the establishment of organized management system to ensure safety during HF applications. A total of 44,751 tons of HF was made by four domestic companies (in 2014); import amount was 95,984 tons in 2014 while 21,579 tons of HF was imported in 2005. The export amount of HF was 2180 tons, of which 2074 ton (China, 1422 tons, U.S. 524 tons, and Malaysia, 128 tons) was exported for the manufacturing of semiconductors. Based on the export and import amounts, it can be inferred that HF was used for manufacturing semiconductors. The industries applications of 161,123 tons of HF were as follows: manufacturing of basic inorganic chemical substance (27,937 tons), manufacturing of other chemical products such as detergents (28,208 tons), manufacturing of flat display (24,896 tons), and manufacturing of glass container package (22,002 tons). In this study, an analysis of the chemical substance flow showed that HF was mainly used in the semiconductor industry as well as glass container manufacturing. Combined with other risk management tools and approaches in the chemical industry, the chemical substance flow analysis (CSFA) can be a useful tool and method for assessment and management. The current CSFA results provide useful information for policy making in the chemical industry and national systems. Graphical abstract Hydrogen fluoride chemical substance flows in 2014 in South Korea.
This work presents the structural and adsorption properties of the CaCO3(-)-rich Corbicula fluminea shell as a natural and economic adsorbent to remove Cd ions from aqueous solutions under batch studies. Experiments were conducted with different contact times, various initial concentrations, initial solution pH and serial biosorbent dosage to examine the dynamic characterization of the adsorption and its influence on Cd uptake capacity. The characterization of the C. fluminea shell using SEM/EDX revealed that the adsorbent surface is mostly impregnated by small particles of potentially calcium salts. The dominant Cd adsorption mechanism is strongly pH and concentration dependent. A maximum Cd removal efficiency of 96.20% was obtained at pH 7 while the optimum adsorbent dosage was observed as 5 g/L. The Langmuir isotherm was discovered to be more suitable to represent the experimental equilibrium isotherm results with higher correlation coefficients (R(2) > 0.98) than Freundlich (R(2)
Removal of H2S (hydrogen sulfide) from biogas is anticipated for higher energy conversion of methane (CH4), while reducing the detrimental impacts of corroding the metal parts in the plant and its hazardous effect on humans and the environment. The introduction of microwave (MW) heating and nitrogen-modification could generate superior adsorbent features, contributing to high H2S removal. Up to date, there is no work reported on the influence of physicochemical characteristics of nitrogen-modified carbon synthesized via MW and conventional heating (TH) methods and their performance in H2S removal. Palm shell activated carbon (PSAC) was functionalized with nitrogen groups via urea impregnation, followed by the synthesis of MW and TH at 950 °C, 500 ml/min of N2 flow rate and 30 min of heating time. MW and TH heating effects on the modified PSAC adsorbent were analysed and compared towards hydrogen sulfide (H2S) removal. PSAC with nitrogen functionalization produced using MW heating (PSAC-MW) demonstrates superior performance, with an adsorption capacity of 356.94 mg/g. The adsorbent sample generated using MW heating exhibited notable properties, including a large surface area and a sponge-like structure, with new pores developed within the current pores. Instead of that, there was an observation of 'hot spot' appearance during the MW heating process, which is believed to be responsible for the development of physical and chemical characteristics of the adsorbent. Thus, it is believed that MW heating was assisted in the development of the adsorbent's properties and at the same time contributed to the high removal of H2S at low adsorption temperature. The utilization of biomass-based adsorbent (PSAC) for H2S removal can address the lignocellulosic waste disposal problem, while mitigating the H2S release from the biogas production plants thus has several environmental merits. This indirectly contributed to zero-waste generation, while overcoming the adverse effects of H2S.
In the present work, we prepared MgO-La2O3-mixed-metal oxides (MMO) as efficient photocatalysts for degradation of organic pollutants. First, a series of MgAl-%La-CO3-layered double hydroxide (LDH) precursors with different contents of La (5, 10, and 20 wt%) were synthesized by the co-precipitation process and then calcined at 600 °C. The prepared materials were characterized by XRD, SEM-EDX, FTIR, TGA, ICP, and UV-vis diffuse reflectance spectroscopy. XRD indicated that MgO, La2O3, and MgAl2O4 phases were found to coexist in the calcined materials. Also, XRD confirms the orthorhombic-tetragonal phases of MgO-La2O3. The samples exhibited a small band gap of 3.0-3.22 eV based on DRS. The photocatalytic activity of the catalysts was assessed for the degradation of two dyes, namely, tartrazine (TZ) and patent blue (PB) as model organic pollutants in aqueous mediums under UV-visible light. Detailed photocatalytic tests that focused on the impacts of dopant amount of La, catalyst dose, initial pH of the solution, irradiation time, dye concentration, and reuse were carried out and discussed in this research. The experimental findings reveal that the highest photocatalytic activity was achieved with the MgO-La2O3-10% MMO with photocatalysts with a degradation efficiency of 97.4% and 93.87% for TZ and PB, respectively, within 150 min of irradiation. The addition of La to the sample was responsible for its highest photocatalytic activity. Response surface methodology (RSM) and gradient boosting regressor (GBR), as artificial intelligence techniques, were employed to assess individual and interactive influences of initial dye concentration, catalyst dose, initial pH, and irradiation time on the degradation performance. The GBR technique predicts the degradation efficiency results with R2 = 0.98 for both TZ and PB. Moreover, ANOVA analysis employing CCD-RSM reveals a high agreement between the quadratic model predictions and the experimental results for TZ and PB (R2 = 0.9327 and Adj-R2 = 0.8699, R2 = 0.9574 and Adj-R2 = 0.8704, respectively). Optimization outcomes indicated that maximum degradation efficiency was attained under the following optimum conditions: catalyst dose 0.3 g/L, initial dye concentration 20 mg/L, pH 4, and reaction time 150 min. On the whole, this study confirms that the proposed artificial intelligence (AI) techniques constituted reliable and robust computer techniques for monitoring and modeling the photodegradation of organic pollutants from aqueous mediums by MgO-La2O3-MMO heterostructure catalysts.
Nanotechnology-based antioxidants and therapeutic agents are believed to be the next generation tools to face the ever-increasing cancer mortality rates. Graphene stands as a preferred nano-therapeutic template, due to the advanced properties and cellular interaction mechanisms. Nevertheless, majority of graphene-based composites suffer from hindered development as efficient cancer therapeutics. Recent nano-toxicology reviews and recommendations emphasize on the preliminary synthetic stages as a crucial element in driving successful applications results. In this study, we present an integrated, green, one-pot hybridization of target-suited raw materials into curcumin-capped gold nanoparticle-conjugated reduced graphene oxide (CAG) nanocomposite, as a prominent anti-oxidant and anti-cancer agent. Distinct from previous studies, the beneficial attributes of curcumin are employed to their fullest extent, such that they perform dual roles of being a natural reducing agent and possessing antioxidant anti-cancer functional moiety. The proposed novel green synthesis approach secured an enhanced structure with dispersed homogenous AuNPs (15.62 ± 4.04 nm) anchored on reduced graphene oxide (rGO) sheets, as evidenced by transmission electron microscopy, surpassing other traditional chemical reductants. On the other hand, safe, non-toxic CAG elevates biological activity and supports biocompatibility. Free radical DPPH inhibition assay revealed CAG antioxidant potential with IC50 (324.1 ± 1.8%) value reduced by half compared to that of traditional citrate-rGO-AuNP nanocomposite (612.1 ± 10.1%), which confirms the amplified multi-potent antioxidant activity. Human colon cancer cell lines (HT-29 and SW-948) showed concentration- and time-dependent cytotoxicity for CAG, as determined by optical microscopy images and WST-8 assay, with relatively low IC50 values (~100 μg/ml), while preserving biocompatibility towards normal human colon (CCD-841) and liver cells (WRL-68), with high selectivity indices (≥ 2.0) at all tested time points. Collectively, our results demonstrate effective green synthesis of CAG nanocomposite, free of additional stabilizing agents, and its bioactivity as an antioxidant and selective anti-colon cancer agent.
Proteins often interact with each other to form complexes and play functional roles in almost all cellular processes. The study of protein-protein interactions is therefore critical to understand protein function and biological pathways. Affinity Purification coupled with Mass Spectrometry (AP-MS) is an invaluable technique for identifying the interaction partners in protein complexes. In this approach, the protein of interest is fused to an affinity tag, followed by the expression and purification of the fusion protein. The affinity-purified sample is then analyzed by mass spectrometry to identify the interaction partners of the bait proteins. In this chapter, we detail the protocol for tandem affinity purification (TAP) based on the use of the FLAG (a fusion tag with peptide sequence DYKDDDDK) and hemagglutinin (HA) peptide epitopes. The immunoprecipitation using dual-affinity tags offers the advantage of increasing the specificity of the purification with lower nonspecific-background interactions.
Biocatalysts have been gaining extra attention in recent decades due to their industrial-relevance properties, which may hasten the transition to a cleaner environment. Carboxylic acid reductases (CARs) are large, multi-domain proteins that can catalyze the reduction of carboxylic acids to corresponding aldehydes, with the presence of adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH). This biocatalytic reaction is of great interest due to the abundance of carboxylic acids in nature and the ability of CAR to convert carboxylic acids to a wide range of aldehydes essentially needed as end products such as vanillin or reaction intermediates for several compounds production such as alcohols, alkanes, and amines. This modular enzyme, found in bacteria and fungi, demands an activation via post-translational modification by the phosphopantetheinyl transferase (PPTase). Recent advances in the characterization and structural studies of CARs revealed valuable information about the dynamics, mechanisms, and unique features of the enzymes. In this comprehensive review, we summarize the previous findings on the phylogeny, structural and mechanistic insight of the domains, post-translational modification requirement, strategies for the cofactors regeneration, the extensively broad aldehyde-related industrial application properties of CARs, as well as their recent immobilization approaches.
A detailed overview toward the advancement of amino acid-based electrochemical sensors on the detection of heavy metals is presented. Discussion is focused on the unique properties of various amino acids (AAs) and its composites which allow them being employed in a diverse range of sensing platforms. Formation of metal-ligand complexes in between metal ions and different AAs has been discussed. The essential insights on the interaction between amino acid-based sensors and target heavy metal ions (HMIs) are provided, along with the discussion on their pros and cons. Voltammetry analysis of metal ions based on various interfaces of electrochemical sensors has been highlighted, together with the incorporation of AAs with organic, inorganic and bio-materials. In all these cases, the amino acid modified electrodes have demonstrated large active surface area with abundant adsorption sites for HMIs. The developed sensors are promising for environmental applications, as evidenced by the high selectivity, high sensitivity, high catalytic activity, and low detection limits. The materials involved, fabrication techniques and its sensing mechanism were comprehensively discussed, and the future outlooks of electrochemical sensing platforms are emphasized in this review.
Replacing conventional fine aggregates with spent mushroom substrate (SMS) is aimed at developing a sustainable lightweight masonry mortar. It is also an alternative solution for the current improper mushroom waste disposals. Density, workability, compressive strength, specific strength, flexural strength, ultrasonic pulse velocity, water absorption, sorptivity, and equivalent CO2 emission in relation to sand reduction in mortars containing 2.5-15.0% (by volume) SMS passing through a 4.75-mm sieve were investigated. As the percentages of replacement increased from 2.5 to 15.0%, the density of the SMS mortar reduced up to 34.8%, with corresponding compressive strengths of 24.96 to 3.37 MPa. Mixes with up to 12.5% SMS met the minimum compressive and flexural strengths as stated in the ASTM C129 standard. In addition, the equivalent CO2 emission of the mixes reduced 15.09% as the SMS content increased while cost-effectiveness increases up to 98.15% until 7.5% SMS replacement. In conclusion, the use of SMS as fine aggregates up to 12.5% is a viable mix design strategy for producing sustainable lightweight mortar with a lower carbon emission.
The use of agricultural by-products such as Moringa oleifera plants is one effort to support the reduction of environmental pollution. Activated carbon produces from agricultural wastes is relatively less expensive and can replace traditional methods such as renewable as well as nonrenewable materials such as petroleum residue and coal. In this study, the removal of bisphenol A from aqueous media was studied using activated carbon produced from M. oleifera pods and peels. A batch adsorption study was carried out by varying the parameters of the adsorption process. A maximum removal percentage of 95.46% was achieved at optimum conditions of 2.5 g L-1 adsorbent dose, pH 7, 60 min contact time and 20 mg L-1 initial concentration of BPA. The BET surface areas of MOP, MOP-AC and MOP-ACZ were found to be 12.60, 4.10 and 45.96 m2/g, respectively. The experimental data were analyzed by Langmuir, Freundlich and Temkin adsorption isotherm models. Equilibrium data fitted well with the Langmuir isotherm with a maximum monolayer adsorption capacity of 20.14 mg g-1. The rates of adsorption were found to conform to the pseudo-second-order kinetics with a good correlation. The results indicate that the M. oleifera activated carbon could be employed as a low-cost alternative to commercial activated carbon in the removal of BPA from water.
Microbial fuel cells (MFCs) are based on the biochemical reaction of microorganisms to decompose organic wastewater for converting chemical energy into power energy. MFCs are considered an environmentally friendly technology that is gaining popularity due to their simultaneous digestion and energy production abilities. To enhance its real application in wastewater treatment, this study proposes to use a non-woven material for replacing the usage of expensive membranes in MFCs. In addition, the study aims to consider a series of different aeration areas of cathode electrodes for finding an optional design. Results have shown that the adoption of non-woven with 0.45 μm can effectively prohibit the diffusion of oxygen into the anode chamber. Moreover, the non-woven material played an important role as an interface between the anode and cathode, enhancing the MFC performance. The usage of suitable non-woven material can replace the role of the membrane when applied in real wastewater applications. The results have shown that the case study where a combination of a 50% aeration area of the cathode electrodes with 25% exposure of the cathode plate in the air yielded relatively better aeration in terms of a higher current density of 250 mA/m2, higher power density of 220 mW/m2, and higher open voltage circuit of 0.4 V, compared to other case studies considered. These results indicate the optimal aeration configuration for MFCs applied in commercial wastewater treatment in the future.
Plants in the genus Erythrina is a potential source of chemical constituents, one of which is flavonoids, which have diverse bioactivities. To date, literature on the flavonoids from the genus Erythrina has only highlighted the phytochemical aspects, so this review article will discuss isolation techniques and strategies for the first time. More than 420 flavonoids have been reported in the Erythrina genus, which are grouped into 17 categories. These flavonoid compounds were obtained through isolation techniques and strategies using polar, semi-polar, and non-polar solvents. Various chromatographic techniques have been developed to isolate flavonoids using column flash chromatography, quick column chromatography, centrifugally accelerated thin-layer chromatography, radial chromatography, medium-pressure column chromatography, semi-preparative high-performance liquid chromatography, and preparative high-performance liquid chromatography. Chromatographic processes for isolating flavonoids can be optimized using multivariate statistical applications such as response surface methodology with central composite design, Box-Behnken design, Doehlert design, and mixture design.
Miri River is a tropical river in Borneo that drains on flat terrain and urbanised area and debauches into the South China Sea. This paper documents the environmental status of this river, and provides an insight into the provenance using bulk chemistry of the sediments, and brings out the geochemical mobility, bioavailability, and potential toxicity of some critical elements based on BCR sequential extraction. The sediments are intense to moderately weathered and recycled products of Neogene sedimentary rocks. The hydrodynamic characteristics of the river favoured an upstream section dominated by fine sand, while the downstream sediments are medium silt. Based on the bulk geochemistry, the Miri River sediments are moderate to considerably contaminated by Cu, Mo, and As in the upstream and by Sb, As and Cu in the downstream. The potential ecological risk values are low except Cu and a significant biological impact is expected in downstream due to Cu, As, Zn and Cr. The mobility, bioavailability and Risk Assessment Code values for Zn and Mn are higher and thus may pose moderate to very high risk to aquatic organisms. Though a high bulk concentration of Cu is observed, the association of Cu with the bioavailable fraction is low.
Deep eutectic solvents (DESs) composed by amino acids (L-arginine, L-proline, L-alanine) as the hydrogen bond acceptors (HBAs) and carboxylic acids (formic acid, acetic acid, lactic acid, levulinic acid) as hydrogen bond donors (HBDs) were prepared and used for the dissolution of dealkaline lignin (DAL). The mechanism of lignin dissolution in DESs was explored at molecular level by combining the analysis of Kamlet-Taft (K-T) solvatochromic parameters, FTIR spectrum and density functional theory (DFT) calculations of DESs. Firstly, it was found that the formation of new hydrogen bonds between lignin and DESs mainly drove the dissolution of lignin, which were accompanied by the erosion of hydrogen bond networks in both lignin and DESs. The nature of hydrogen bond network within DESs was fundamentally determined by the type and number of functional groups in both HBA and HBD, which affected its ability to form hydrogen bond with lignin. One hydroxyl group and carboxyl group in HBDs provided active protons, which facilitated proton-catalyzed cleavage of β-O-4, thus enhancing the dissolution of DESs. The superfluous functional group resulted in more extensive and stronger hydrogen bond network in the DESs, thus decreasing the lignin dissolving ability. Moreover, it was found that lignin solubility had a closed positive correlation with the subtraction value of α and β (net hydrogen donating ability) of DESs. Among all the investigated DESs, L-alanine/formic acid (1:3) with the strong hydrogen-bond donating ability (acidity), weak hydrogen-bond accepting ability (basicity) and small steric-hindrance effect showed the best lignin dissolving ability (23.99 wt%, 60 °C). On top of that, the value of α and β of L-proline/carboxylic acids DESs showed some positive correlation with the global electrostatic potential (ESP) maxima and minima of the corresponding DESs respectively, indicating the analysis of ESP quantitative distributions of DESs could be an effective tool for DESs screening and design for lignin dissolution as well as other applications.
In biomedical implant technology, nanosurface such as titania nanotube arrays (TNA) could provide better cellular adaptation, especially for long-term tissue acceptance response. Mechanotransduction activities of TNA nanosurface could involve the cytoskeleton remodeling mechanism. However, there is no clear insight into TNA mechano-cytoskeleton remodeling activities, especially computational approaches. Epithelial cells have played critical interface between biomedical implant surface and tissue acceptance, particularly for long-term interaction. Therefore, this study investigates genomic responses that are responsible for cell-TNA mechano-stimulus using epithelial cells model. Findings suggested that cell-TNA interaction may improve structural and extracellular matrix (ECM) support on the cells as an adaptive response toward the nanosurface topography. More specifically, the surface topography of the TNA might improve the cell polarity and adhesion properties via the interaction of the plasma membrane and intracellular matrix responses. TNA nanosurface might engross the cytoskeleton remodeling activities for multidirectional cell movement and cellular protrusions on TNA nanosurface. These observations are supported by the molecular docking profiles that determine proteins' in silico binding mechanism on TNA. This active cell-surface revamping would allow cells to adapt to develop a protective barrier toward TNA nanosurface, thus enhancing biocompatibility properties distinctly for long-term interaction. The findings from this study will be beneficial toward nano-molecular knowledge of designing functional nanosurface technology for advanced medical implant applications.
In this study, biochar produced from sunflower seeds husk was activated through ZnCl2 to support the NiCo2O4 nanoparticles (NiCo2O4@ZSF) in catalytic activation of peroxymonosulfate (PMS) toward tetracycline (TC) removal from aqueous solution. The good dispersion of NiCo2O4 NPs on the ZSF surface provided sufficient active sites and abundant functional groups for the adsorption and catalytic reaction. The NiCo2O4@ZSF activating PMS showed high removal efficiency up to 99% after 30 min under optimal condition ([NiCo2O4@ZSF] = 25 mg L-1, [PMS] = 0.04 mM, [TC] = 0.02 mM and pH = 7). The catalyst also exhibited good adsorption performance with a maximum adsorption capacity of 322.58 mg g-1. Sulfate radicals (SO4•-), superoxide radical (O2•-), and singlet oxygen (1O2) played a decisive role in the NiCo2O4@ZSF/PMS system. In conclusion, our research elucidated the production of highly efficient carbon-based catalysts for environmental remediation, and also emphasized the potential application of NiCo2O4 doped biochar.