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1.
J Cancer Res Ther ; 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38261421

ABSTRACT

ABSTRACT: Maxillofacial rehabilitation of an orbital defect plays a crucial role in enhancing the esthetics of the facial defect. The eye is a vital organ, the loss of which requires a customized approach for post-defect rehabilitation. Advanced treatment option such as implant-supported orbital prosthesis has a superior outcome in terms of retention and esthetics, but due to economic factor, it is not affordable for all patients. This case report describes a simplified rehabilitation technique for a patient with an orbital defect where retention is achieved by spectacles and satisfactory esthetics are obtained.

2.
Bioresour Technol ; 344(Pt A): 126240, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34737164

ABSTRACT

Lignin is the world's second most prevalent biomaterial, but its effective value-added product valorization methods are still being developed. The most common preparation processes for converting lignin to platform chemicals and biofuels are fragmentation and depolymerization. Due to its structural diversity, fragmentation generally produces a variety of products, necessitating tedious separation and purifying methods to isolate the desired products. Bacterial-based techniques are commonly utilized for lignin fragmentation due to their high metabolitic activity. Recent advancements in lignin valorization utilizing bacteria, such as lignin decomposing microbes and major pathways involved that can breakdown lignin into various valuable products namely lipids, furfural, vanillin, polyhydroxybutyrate, poly lactic acid blends were discussed in this review. This review also covers the genetic and fermentation methodologies to enhance lignin decomposition, challenges and future trends of microbe based lignin valorization.


Subject(s)
Biofuels , Lignin , Bacteria/metabolism , Fermentation , Lignin/metabolism , Lipids
3.
J Conserv Dent ; 24(5): 491-495, 2021.
Article in English | MEDLINE | ID: mdl-35399770

ABSTRACT

Background: Proper hybrid layer formation lays the foundation of resin-dentin bonding. The resin infiltration in demineralized dentin collagen couples with the adhesive/resin composites in the mineralized dentin surface. However, the activation of enzymatic activity in the collagen matrix can degrade the hybrid layer. Over the time, it leads to reduced bond strength. Mainly, the enzymes involved are matrix metalloproteinases (MMPs) which are involved in degrading most of the extracellular matrix components. Aloe vera is an herb with an anti-inflammatory effect, but its role in human dentin as an enzyme inhibitor has not been verified yet. Aims: The purpose of the study was designed for evaluating the inhibitory action of Aloe vera on MMP in human dentin with and without dentin bonding agents. Materials and Methods: A total of 15 freshly extracted healthy human teeth were collected and stored at 4°C until use. The roots were separated. The enamel and remnant pulp tissue were removed, and collected teeth were pulverized with liquid nitrogen in the minimum volume of 50-mM phosphate buffer to obtain dentin powder extract. The dentin powder extract is the source of MMPs, and therefore, the extract was treated with A. vera solution and incubated to assess the enzyme inhibition by the plate assay method and zymographic analysis. Results: A. vera treated sample with and without dentin bonding agent showed inhibition of dentin MMP's activity by plate assay method and confirmed by zymogram analysis. Conclusions: A. vera has the potential for inhibiting the MMPs enzyme activity of human dentin collagen with and without dentin bonding agents.

4.
Methods Mol Biol ; 1853: 133-138, 2018.
Article in English | MEDLINE | ID: mdl-30097938

ABSTRACT

Activity staining or zymography is a technique to detect enzymes based on their function/activity toward a specific substrate. Multiple enzyme-producing microbes secrete enzymes along with other proteins at varying time points during fermentation. The technique of zymography can be used to detect functionality of enzymes in complex protein/other enzyme mixtures. The protein bands corresponding to specific enzyme among other enzymes/proteins can be located by polyacrylamide gel electrophoresis (PAGE) followed by zymogram analysis. This can be employed to locate the secretion pattern of protein/enzyme from intracellular region to extracellular medium. Here we describe simple method for detection and cellular localization of esterases and protease secreted by single microbial strain in one PAGE gel.


Subject(s)
Culture Media, Conditioned/chemistry , Electrophoresis, Polyacrylamide Gel , Enzyme Assays , Enzymes , Fermentation , Enzyme Assays/methods , Enzymes/chemistry , Esterases/chemistry , Peptide Hydrolases/chemistry , Solutions , Staining and Labeling/methods
5.
Int J Biomed Sci ; 13(1): 1-5, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28533730

ABSTRACT

Forensic Odontology a branch of Forensic sciences uses the skill of the dentist in personal identification during mass calamities, sexual assault and child abuse to name a few. This branch not stranger to many has been growing tenfold in its potential and its ability to bring the forlorn to justice where a dental remains is the only available evidence. It's role and importance in the judiciary is fast growing and hence in depth knowledge in this field seems more than justified.

6.
Prep Biochem Biotechnol ; 47(4): 323-332, 2017 Apr 21.
Article in English | MEDLINE | ID: mdl-27737615

ABSTRACT

The simultaneous production of intracellular esterase and extracellular protease from the strain Lysinibacillus fusiformis AU01 was studied in detail. The production was performed both under batch and fed-batch modes. The maximum yield of intracellular esterase and protease was obtained under full oxygen saturation at the beginning of the fermentation. The data were fitted to the Luedeking-Piret model and it was shown that the enzyme (both esterase and protease) production was growth associated. A decrease in intracellular esterase and increase in the extracellular esterase were observed during late stationary phase. The appearance of intracellular proteins in extracellular media and decrease in viable cell count and biomass during late stationary phase confirmed that the presence of extracellular esterase is due to cell lysis. Even though the fed-batch fermentation with different feeding strategies showed improved productivity, feeding yeast extract under DO-stat fermentation conditions showed highest intracellular esterase and protease production. Under DO-stat fed-batch cultivation, maximum intracellular esterase activity of 820 × 103 U/L and extracellular protease activity of 172 × 103 U/L were obtained at the 16th hr. Intracellular esterase and extracellular protease production were increased fivefold and fourfold, respectively, when compared to batch fermentation performed under shake flask conditions.


Subject(s)
Bacillaceae/enzymology , Bacillaceae/metabolism , Batch Cell Culture Techniques/methods , Esterases/metabolism , Fermentation , Industrial Microbiology/methods , Peptide Hydrolases/metabolism , Bacillaceae/growth & development , Bioreactors , Kinetics
7.
Appl Biochem Biotechnol ; 172(2): 910-32, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24122712

ABSTRACT

A new organic solvent-tolerant strain Bacillus megaterium AU02 which secretes an organic solvent-tolerant protease was isolated from milk industry waste. Statistical methods were employed to achieve optimum protease production of 43.6 U/ml in shake flask cultures. The productivity of the protease was increased to 53 U/ml when cultivated under controlled conditions in a 7-L fermentor. The protease was purified to homogeneity by a three-step process with 24 % yield and specific activity of 5,375 U/mg. The molecular mass of the protease was found to be 59 kDa. The enzyme was active over a wide range of pH (6.0­9.0), with an optimum activity at pH 7.0 and temperature from 40 to 70 °C having an optimum activity at 50 °C. The thermal stability of the enzyme increased significantly in the presence of CaCl2, and it retained 90 % activity at 50 °C for 3 h. The Km and Vmax values were determined as 0.722 mg/ml and 0.018 U/mg respectively. The metalloprotease exhibited significant stability in the presence of organic solvents with log P values more than 2.5, nonionic detergents and oxidising agent. An attempt was made to test the synthesis of aspartame precursor (Cbz-Asp-Phe-NH2) which was catalysed by AU02 protease in the presence of 50 % DMSO. These properties of AU02 protease make it an ideal choice for enzymatic peptide synthesis in organic media.


Subject(s)
Adaptation, Physiological/drug effects , Bacillus megaterium/enzymology , Calcium/pharmacology , Organic Chemicals/toxicity , Peptide Hydrolases/isolation & purification , Peptide Hydrolases/metabolism , Solvents/toxicity , Analysis of Variance , Aspartame/metabolism , Bacillus megaterium/drug effects , Bacillus megaterium/growth & development , Bioreactors/microbiology , Chromatography, High Pressure Liquid , Chromatography, Reverse-Phase , Electrophoresis, Polyacrylamide Gel , Enzyme Stability/drug effects , Hydrogen-Ion Concentration , Ions , Kinetics , Metals/pharmacology , Oxidation-Reduction/drug effects , Phylogeny , Reproducibility of Results , Substrate Specificity/drug effects , Surface-Active Agents/pharmacology , Temperature , Time Factors
8.
Anal Biochem ; 448: 38-40, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24316114

ABSTRACT

Lipases and esterases are hydrolytic enzymes and are known to hydrolyze esters with unique substrate specificity and acyl chain length selectivity. We have developed a simple competitive multiple substrate assay for determination of acyl chain length selectivity of lipases/esterases using RP-HPLC with UV detection. A method for separation and quantification of 4-nitrophenyl fatty acid esters (C4-C18) was developed and validated. The chain length selectivity of five lipases and two esterases was determined in a multisubstrate reaction system containing equimolar concentrations of 4-nitrophenyl esters (C4-C18). This assay is simple, reproducible, and a useful tool for determining chain length selectivity of lipases/esterases.


Subject(s)
Chromatography, High Pressure Liquid , Chromatography, Reverse-Phase , Enzyme Assays/methods , Esterases/metabolism , Lipase/metabolism , Esters , Fatty Acids/chemistry , Fatty Acids/metabolism , Hydrolysis , Kinetics , Nitrophenols/chemistry , Spectrophotometry, Ultraviolet , Substrate Specificity
9.
Asia Pac J Ophthalmol (Phila) ; 3(6): 348-53, 2014.
Article in English | MEDLINE | ID: mdl-26107977

ABSTRACT

PURPOSE: We hypothesize that because of the anisotropic properties of the cornea, there should be a nonuniform change in birefringence with an increase in intraocular pressure (IOP). In this in vitro study, anisotropic properties, stress distribution within the cornea, and the effect of IOP on changes in stress level were investigated. DESIGN: Button inflation tests for deformation with polarization sensitive optical coherence tomography were used to demonstrate optical and material anisotropy on ex vivo human corneas. METHODS: Inflation tests were performed on human donor corneoscleral rims. Using a turntable and hydrostatic column, each corneoscleral rim was subjected to a hydrostatic pressure of 0, 10, 15, and 20 mm Hg. At each pressure step, 4 scans at 0, 45, 90, and 135 degrees were taken by a polarization sensitive optical coherence tomography system, and the birefringence images and normal intensity-based images were recorded; images were later compiled for analysis. RESULTS: The retardation changed with the axis of orientation (P [T ≤ t] 1-tailed = 0.025) and IOP (P [T ≤ t] 1-tailed = 0.019). Optical thickness of the cornea decreased with increasing IOP. CONCLUSIONS: The optical properties of the cornea are modified with change in IOP. This is not uniform because of distinct anisotropic properties. Anisotropic properties may unpredictably affect the optical quality of cornea during or after the surgeries. Changes in corneal birefringence can be also used as a tool for measuring the IOP of the eye.

10.
Methods Mol Biol ; 869: 579-84, 2012.
Article in English | MEDLINE | ID: mdl-22585523

ABSTRACT

Protein identification in polyacrylamide gel electrophoresis (PAGE) requires post-electrophoretic steps like fixing, staining, and destaining of the gel, which are time-consuming and cumbersome. A new method for direct visualization of protein bands in PAGE has been developed using meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) as a dye without the need for any post-electrophoretic steps; thus, separation and recovery of enzymes become much easier for further analysis. Activity staining was carried out to show that the biochemical activity of the enzymes was preserved after electrophoresis.


Subject(s)
Coloring Agents/chemistry , Enzymes/chemistry , Porphyrins/chemistry , Staining and Labeling/methods , Buffers , Coloring Agents/chemical synthesis , Electrophoresis, Polyacrylamide Gel/methods , Enzyme Assays/methods , Enzymes/isolation & purification , Porphyrins/chemical synthesis , Protein Conformation
11.
Appl Microbiol Biotechnol ; 58(4): 539-42, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11954803

ABSTRACT

A lipoxygenase-1 (LOX-1) inhibitor was isolated from the fermented broth of Aspergillus niger CFTRI 1105. It was purified, using column and preparative thin layer chromatography. 1H NMR and GC-MS examination revealed the structure of the inhibitor to be 2-(2'-methyl, 4'-hydroxyphenyl), 2-(4"hydroxyphenyl)-propane with a molecular weight of 242 and the molecular formula C,6H18O2. This bisphenol-derivative inhibitor shows 50% inhibition of soybean LOX-I at 0.98 mM concentration. The activity of this inhibitor was compared with commercial bisphenol A and its structural analogues, butylhydroxyanisole and butylhydroxytoluene in an attempt to understand the role of functional groups affecting lipoxygenase activity.


Subject(s)
Aspergillus niger/chemistry , Lipoxygenase Inhibitors/isolation & purification , Lipoxygenase/metabolism , Chromatography, Thin Layer , Lipoxygenase Inhibitors/chemistry , Lipoxygenase Inhibitors/pharmacology , Magnetic Resonance Spectroscopy , Molecular Weight
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