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1.
Int J Biol Macromol ; 254(Pt 3): 127954, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37951425

ABSTRACT

Sodium alginate (SA) is a biodegradable macromolecule which is used to synthesize nanocomposites and their further use as catalysis. Zinc oxide (ZnO) and nitrogen doped carbon nitride (ND-C3N4) nanoparticles are prepared using solvothermal and hydrothermal methods, respectively. ZnO/ND-C3N4/SA nanocomposites are successfully synthesized by employing in-situ polymerization. The presence of essential functional groups is confirmed by Fourier transform infrared (FTIR) spectroscopic analysis. Controlled spherical morphology for ZnO nanoparticles, with an average diameter of ∼52 nm, is shown by Scanning electron microscopic (SEM) analysis, while rice-like grain structure with an average grain size ∼62 nm is exhibited by ND-C3N4 nanoparticles. The presence of required elements is confirmed by Energy dispersive X-ray spectroscopic (EDX) analysis. The crystalline nature of nanocomposites is verified by X-ray diffraction spectroscopic (XRD) analysis. The investigation of the catalytic efficiency for degradation and reduction of various organic dyes is carried out on nanoparticles and nanocomposites. Thorough examination and comparison of parameters, such as apparent rate constant (kapp), reduction time, percentage reduction, reduced concentration and half-life, are conducted for all substrates. The nanocomposites show greater efficiency than nanoparticles in both reactions: catalytic reduction and catalytic degradation.


Subject(s)
Nanocomposites , Zinc Oxide , Zinc Oxide/chemistry , Alginates , Spectroscopy, Fourier Transform Infrared , Nanocomposites/chemistry , Catalysis
2.
Appl Biochem Biotechnol ; 194(4): 1775-1789, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35000123

ABSTRACT

Herein, laccase from Trametes versicolor was used to fabricate carrier-free cross-linked laccase crystals (CLLCs) and deployed as a robust catalyst for waste effluent treatment. The surface morphology and involvement of functional group attributes of CLLCs were scrutinized by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). As fabricated CLLCs were subjected to kinetic characterization by assessing the effects of pH environment, thermal profile, and substrate (determination of Km and Vmax) on the activity. A fully characterized CLLCs fraction was used to treat synthetic dyes containing waste effluents taken from various industries, i.e., Chenab Textile Industry, M-tax, Sitara, and National Silk & Rayon Mills. Degradation profile revealed 36.8%, 27.6%, 39.9%, and 26.4% degradation of Chenab Textile Industry, M-tax, Sitara, and National Silk & Rayon Mills, respectively, by the free form of laccase, whereas the biocatalytic activity of CCLCs led to 78.6%, 75.6%, 85.5%, and 63.3% degradation of those effluents. The decrease in peak and mass region alongside the presence of new peaks in GC-MS affirms the effective decolorization of contaminated waste effluents. CLLCs retained over 70% and 50% of their degradation activity after 3 and 5 cycles, respectively. In conclusion, CLLCs might represent a robust bioprocess to improve the usability of laccase for various synthetic dyes containing waste effluents to diminish environmental pollution from the dye-based industries.


Subject(s)
Laccase , Trametes , Biodegradation, Environmental , Coloring Agents/metabolism , Industrial Waste/analysis , Laccase/metabolism , Textile Industry , Textiles
3.
Molecules ; 26(18)2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34577076

ABSTRACT

A series of (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline analogs synthesized in considerable yields through Suzuki cross-coupling reactions. Various electron donating and withdrawing functional moieties were successfully incorporated under the employed reaction conditions. Reaction of 4-bromo-2-methylaniline (1) with 3-bromothiophene-2-carbaldehyde (2b) in the existence of glacial acetic acid, provided (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline (3b) in excellent yield (94%). Suzuki coupling of 3b with different boronic acids in the presence of Pd(PPh3)4/K3PO4 at 90 °C led to the synthesis of the monosubstituted and bisubstituted products 5a-5d and 6a-6d in moderate yields (33-40% and 31-46%, respectively). Density functional theory (DFT) investigations were performed on different synthesized analogues 5a-5d, 6a-6d to determine their structural characteristics. The calculations provide insight into the frontier molecular orbitals (FMOs) of the imine-based analogues and their molecular electrostatic potential (MESP). Reactivity descriptors like ionization energy (I), electron affinity (A), chemical hardness (ƞ) and index of nucleophilicity have been calculated for the first time for the synthesized molecules.

4.
J Food Biochem ; 44(8): e13320, 2020 08.
Article in English | MEDLINE | ID: mdl-32542898

ABSTRACT

Herein, the methanolic extract of Rumex hastatus was prepared and subjected to silica gel column chromatographic separation for purification. The chromatographic analysis yielded four bioactive compounds namely, 1,8-dihydroxy-3-methyl-anthraquinone (C1, chrysophanol), 3-methoxy-7-methyl-1,5-dihydroxy-anthraquinone (C2), 6-methyl-1,3,7-trihydroxy-anthraquinone (C3), and 4-hydroxycinnamic acid (C4). The structures of all the isolated bio-entities were elucidated by spectroscopic analysis (1D, 2D-NMR, and MS). The biological potentialities of bioactive compounds were evaluated by determining their antioxidant and anti-urease activities. The results revealed that compound 1 showed the highest nitrite radical scavenging activity (IC50  = 0.39 mM) followed by C2 and C4 (IC50  = 0.45) mM and C3 (IC50  = 0.47 mM). Similarly, the determined IC50  values for anti-urease activity were C2 (IC50  = 0.39 mM), C1 (IC50  = 0.40), C4 (IC50  = 0.41), and C3 (IC50  = 44). Molecular docking study revealed maximum interactions among the hydroxyl group of all compounds. In conclusion, Rumex hastatus extract could be a promising alternative to chemical additives in pharmaceutical industries due to its noteworthy biological activities. PRACTICAL APPLICATIONS: As we have shown in this study that Rumex hastatus is a prolific source of biologically active compounds with potent antioxidant and anti-urease activities, therefore, R. hastatus extract could be used as a promising alternative to chemical additives in pharmaceutical industries due to its unique compounds and noteworthy biological activities.


Subject(s)
Rumex , Antioxidants/pharmacology , Molecular Docking Simulation , Plant Extracts/pharmacology , Urease
5.
Materials (Basel) ; 13(1)2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31861758

ABSTRACT

Herein, a systematic study of the enhanced physicochemical properties of lanthanide doped (La-doped) bismuth molybdate (Bi2MoO6) is performed. For this purpose, Bi2MoO6 and La-doped Bi2MoO6 were prepared by the sol-gel method. BiCl3, Na2MoO4·2H2O, and LaCl3·7H2O were taken as the main precursors while sodium dodecyl sulfate was used as a surfactant. Both Bi2MoO6 and La-doped Bi2MoO6 were calcined at 650 °C for 2 h. These prepared materials were characterized by spectroscopic techniques such as UV-VIS, FT-IR, XRD, photoluminescence, XPS, along with other techniques such as SEM, TEM, TGA, etc. The investigation of luminescence behavior revealed that the La-doped Bi2MoO6 nanocomposite exhibited much greater luminescence compared to the undoped Bi2MoO6. The photocatalytic behavior of the prepared materials was explored by studying the degradation of methylene blue (MB) at room temperature. The degradation of MB with Bi2MoO6 and La-doped bismuth molybdate were observed to be 68% and 75% @ 45 s, respectively, indicating an enhancement of catalytic performance due to the La doping.

6.
Article in English | MEDLINE | ID: mdl-30019654

ABSTRACT

BACKGROUND: Diabetes Mellitus (DM) is an advanced and chronic endocrine disorder characterized by an insufficiency of insulin secretion from pancreatic ß-cells and liver, adipose tissues, and skeletal muscles. OBJECTIVE: The main objective of this study is to understand the mechanism and genes which are responsible for the prevalence of diabetes. The study also covers various types of diabetic complications with special reference to insulin role and defects. METHODS: The scientific literature and patents were reviewed and analyzed based on their suitability and relevance to the theme of the study. The scientific literature was covered from the authentic databases such as Elsevier, Springer, and Bentham Science. The patents were reviewed from http://www.freepatentsonline.com. RESULTS: Glucokinase (ATP: D-glucose-6-phosphotransferase; GCK), initiates glycolysis and acts as a glucose sensor and metabolic signal producer in liver and pancreas. PCR-sequencing showed qualitative differences in diabetic patients in comparison to healthy subjects. Glucokinase is the most important component in glucose detection of pancreatic islet beta cells in diabetes because glucokinase mutations can be one of the most common single gene disorders described. It is known that a genetic variation of a human glucokinase gene, including a point mutation, causes MODY, the concentration of plasma glucose increased and it is supposed to be the cause of diabetes of the present study subjects. Owing to hyperglycemia and individual components of the insulin resistance (metabolic) syndrome, people with Type II DM are prone to the high threat for microvascular complications (including nephropathy, retinopathy, and neuropathy) and macrovascular complications (such as Ischemic Heart Disease). There were also significant differences (P < 0.0001) in glycation levels (0.90, 0.4838mole/mole), random blood sugar (348.8, 105.8mg/dL), cholesterol levels (235.3, 161.8mg/dL), low density lipoprotein in diabetic subjects (155.3, 28.46mg/dL) and in healthy donors. GCK gene mutations were found in 70% of the patients while 30% are non-mutated. CONCLUSION: In conclusion, lipids, glucose, and protein play an essential role in the initiation of AGE's or diabetic complications (Micro and Macrovascular Complications). The importance of the clinical results should also be recognized in the genetic analysis of heterogeneous disorders as NIDDM/ Type II DM.


Subject(s)
Diabetes Complications/genetics , Glucokinase/genetics , Insulin/physiology , Polymorphism, Genetic , Diabetes Complications/etiology , Diabetes Mellitus, Type 1/etiology , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 2/etiology , Diabetes Mellitus, Type 2/genetics , Humans , Insulin Secretion
7.
Int J Biol Macromol ; 95: 54-62, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27825994

ABSTRACT

In the current study, different bio-polymers such as agar-agar, polyacrylamide and gelatin were utilized as bolster materials for the immobilization of a fungal laccase through entrapment approach. Among the polymers, agar-agar matrix most firmly encapsulated the enzyme yielding significant laccase immobilization (79.65±2.55%). Immobilization prolonged the reaction time of laccase and agar-agar, polyacrylamide and gelatin entrapped laccases displayed maximum catalytic activities after 10.0, 15.0 and 10.0min of reaction, respectively, as compared to free counterpart (5.0min). It also increased the optimal temperature by 5.0-10°C and provided an alkaline shift of the pH optima to agar-agar and gelatin entrapped laccase, while, in case of polyacrylamide, optimum pH was displaced to acidic region. Kinetic data revealed that Km(app) values were slightly increased while Vmax values were decreased as compared to free counterpart. Polymers encapsulation led to significant improvement in activity against thermal denaturation. After 180min at 60°C, the enzymes preserved 28.1±0.9, 48.6±1.3 and 32.5±1.8% residual activities, respectively, whereas, the free enzyme was completely inactive. Immobilization enabled the enzymes to resist a number of different effectors including metal ions, inhibitors/denaturants and chelating agents. Moreover, the resulted modified laccases displayed good recycling capability for substrate-oxidation reactions in several successive batches. In summary, the tremendously improved attributes of polymers-encapsulated enzymes display a high potential for various applications in different industrial sectors.


Subject(s)
Biocatalysis , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Laccase/chemistry , Laccase/metabolism , Polymers/chemistry , Trametes/enzymology , Enzyme Stability , Hydrogen-Ion Concentration , Kinetics , Temperature
8.
Water Environ Res ; 82(4): 357-61, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20432654

ABSTRACT

A locally isolated white rot fungus Ganoderma lucidum IBL-05 was used for development of a bioremediation process for original textile industry effluents. Dye-containing effluents of different colors were collected from the Arzoo (maroon), Ayesha (yellow), Ittemad (green), Crescent (navy blue) and Magna (yellowish) textile industries of Faisalabad, Pakistan. G. lucidum IBL-05 was screened for its decolorization potential on all the effluents. Maximum decolorization (49.5 %) was observed in the case of the Arzoo textile industry (ART) effluent (lambda(max) = 515 nm) on the 10th day of incubation. Therefore, the ART effluent was selected for optimization of its decolorization process. Process optimization could improve color removal efficiency of the fungus to 95% within only 2 days, catalyzed by manganese peroxidase (1295 U/mL) as the main enzyme activity at pH 3 and 35 degrees C using 1% starch supplemented Kirk's basal medium. Nitrogen addition inhibited enzyme formation and effluent decolorization. The economics and effectiveness of the process can be improved by further process optimization.


Subject(s)
Coloring Agents/metabolism , Ganoderma/metabolism , Industrial Waste , Textile Industry , Waste Disposal, Fluid/methods , Bioreactors , Coloring Agents/chemistry , Water/chemistry
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