Theoretical and Experimental Insights of Benzimidazole Catalyzed by the Epoxy-Acrylic Acid Reaction.

This study focuses on the experimental and molecular-level investigation of epoxy acrylate formation. Epoxy acrylate vinyl ester resin was prepared by a reaction of diglycidyl ether of bisphenol-A-based epoxy resin and acrylic acid, using benzimidazole as a catalyst. It was confirmed that benzimidazole can effectively catalyze this reaction. FTIR analysis of the product revealed a simple addition esterification reaction between the epoxide group and carboxylic group of acrylic acid excluding the side reactions (e.g., etherification). DFT computational studies were performed to theoretically explore the insights of reaction mechanisms. The calculations revealed that the benzimidazole-catalyzed reaction dominates the uncatalyzed reaction. A comparison of calculated activation energies showed that concerted mechanisms are less significant in such reactions owing to their high activation barriers.

An Overview of Synthetic Routes of Pharmaceutically Important Pyranopyrazoles.

Pyranopyrazoles are bicyclic nitrogen-containing heterocycles having broadspectrum bioactivities, which may act as anti-cancer, anti-inflammatory, antibacterial, antifungal, insecticidal and molluscicidal agents. Pyranopyrazoles have become an attractive scaffold for the discovery of new drugs due to the diverse range of bioactivities associated with this nucleus. In this review, we have focused on the medicinal importance of pyranopyrazole derivatives and highlighted different routes for the synthesis of pyranopyrazole derivatives using inexpensive and commonly available starting materials.

Biologically Synthesized Peptides Show Remarkable Inhibition Activity against Angiotensin-Converting Enzyme: A Promising Approach for Peptide Development against Autoimmune Diseases.

Angiotensin-converting enzyme (ACE) regulates several biological functions besides its vital role in immune functions. ACE is elevated in immune cells in inflammatory diseases including atherosclerosis, granuloma, chronic kidney disease, and also autoimmune diseases, like multiple sclerosis, rheumatoid arthritis, and type I diabetes. No significant information prevails in the literature regarding the isolation, identification, and profiling of potential ACE inhibitory peptides. In the present study, indigenous crop varieties like seeds (peanut, corn, oat, sunflower, chickpea, parsley, cottonseed, papaya, sesame, and flaxseed) were used to evaluate their ACE inhibition activity. Variables including hydrolysis time, enzyme-to-substrate ratio (E/S), pH, and temperature were standardized to acquire the most suitable and optimum ACE inhibition activity. Seeds of cotton, chickpea, and peanuts displayed remarkably maximum ACE inhibition activity than other plants. The study disclosed that maximum ACE inhibitory activity (86%) was evaluated from cottonseed at pH 8.0, temperature of 45°C, hydrolysis time of 2 hrs, and enzyme to the substrate (E/S) ratio of 1 : 5 followed by peanuts (76%) and chickpea (55%). SDS-PAGE confirmed that vicilin protein is present in cottonseed and peanut seed while cruciferin and napin proteins are present in chickpeas. LC-MS/MS analysis disclosed potential novel peptides in hydrolyzed cottonseed that can be ascribed as potential ACE inhibitors which have never been reported and studied earlier. The current study further showed that cottonseed peptides due to their promising ACE inhibitory activity can be a valuable source in the field of ACE inhibitor development.

Analysis of lead, cadmium, and arsenic in colored cosmetics marketed in Pakistan.

Heavy metal contamination of the cosmetic products poses potential harm for consumers' health. We aimed to determine the concentration of Arsenic (As), Lead (Pb), and Cadmium (Cd) in locally available colored cosmetics such as lipsticks, foundation cream, facial powder, and eye shadows. We determined concentration of As, Pb, and Cd in 40 samples of colored cosmetics by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and determined significant differences in As and Cd concentrations across the colored cosmetics. We detected a high concentration of Pb and As in lipstick and eye shadow samples. Concentration of Pb and Cd in the samples of foundation creams was at safe level. Most of the cosmetic samples contained heavy metals above safe levels posing a threat to the health of female consumers who use them for long periods. Regulatory bodies in Pakistan must adopt and enforce international standards for colored cosmetics.

Development of One Pot Strategy for Hyper Production and In Vivo Evaluation of Lovastatin.

The aim of this project was to improve the Aspergillus terreus strain and pretreatment of sugarcane bagasse as carrier substrate for bulk production of lovastatin, a cholesterol-lowering drug, in solid state fermentation. Sugarcane bagasse was treated with alkali (1-3% NaOH) for the conversion of complex polysaccharides into simple sugars for better utilization of carrier substrate by microorganism for maximum lovastatin production. Ethidium bromide (time of exposure 30-180 min) was used to induce mutation in Aspergillus terreus and the best mutant was selected on the basis of inhibition zone appeared on petri plates. Fermented lovastatin was quantified by high-performance liquid chromatography. The fermented lovastatin, produced by parent and mutant Aspergillus terreus strain, was checked on body weight, blood glucose and serum cholesterol, ALT, AST, HDL-C, LDL-C, TG and TC levels of rats for their cholesterol lowering capacity. Our results indicate that selected strain along with 2% NaOH treated sugar cane bagasse was best suitable for bulk production of lovastatin by fermentation and fermented lovastatin effectively lower the cholesterol level of rats.

Synthesis of a Fluorescent Whitening Molecule and its Application to Wool Fibres.

AIM AND OBJECTIVE: Reactive dye molecules are commonly employed to dye or modify colour characteristics of wool fibres. Yellowness of wool fibres poses a challenge and here, we report synthesis of a reactive fluorescent molecule and its application to wool fibres to reduce yellowness of the wool fibre and improve its colour features. MATERIAL AND METHODS: The new molecule was based upon 7-amino-4-methylcoumarin (AMC) and 2,4,6- trichloro-1,3,5-triazine (TZT). The synthesis involved a two-step chemical reaction, initiated by the nucleophilic substitution of a chloro group on the triazine ring with the hydroxyl group of 4-hydroxybenzenesulfonic acid. The substitution of 2nd chloro group at triazine ring with the amino group of 7-amino-4-methylcoumarin resulted in a novel molecule with a monofunctional reactive chloro group (AMC-MCT molecule). RESULTS: The new molecule was applied to the wool fibres using exhaust dyeing method. This exhibited a high exhaustion value; however low fixation and total efficiency values were observed for the new molecule. The resultant wool fibres exhibited fluorescence which shows that aminocoumarin fluorophore retained its fluorescence when incorporated in the new molecule. An assessment of the molecule for yellowness index in a controlled exposure to UV radiation suggested an improvement in whiteness of wool fibre. CONCLUSION: A novel aminocoumarin based fluorescent whitening molecule 2 has been synthesised and applied to the wool fibres. The new molecule continued to exhibit fluorescence after its application to the wool fibres. These results will encourage researchers to explore further possibilities for reactive whitening agent for wool fibres.

Bioremediation of Synthetic and Industrial Effluents by Aspergillus niger Isolated from Contaminated Soil Following a Sequential Strategy.

The present study aimed to assess and compare the ability to remediate synthetic textile and industrial wastewaters by Fenton treatment, a biological system and sequential treatments using Aspergillus niger (A. niger). All studied treatments were found to be effective in decolorization of the effluents under study. Fenton treatment followed by A. niger showed excellent potential for the maximum decolorization of the synthetic and industrial effluents under study. The effectiveness of sequential treatment was evaluated by water quality parameters such as total organic carbon (TOC), Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) before and after each treatment. The results indicated that A. niger is an effective candidate for detoxification of textile wastewaters.

Separation of polysorbates by liquid chromatography on a HILIC column and identification of peaks by MALDI-TOF MS.

Polysorbates can be separated according to their functionality and architecture by liquid chromatography on a hydrophilic interaction chromatography (HILIC) column in acetone-water mobile phases containing 90-97% acetone. The different polymer homologous series are separated according to the number of terminal hydroxy groups and elute as narrow peaks. The hydrophilic part (ethoxylates of sorbitan, isosorbide, and poly(ethyleneglycol)) and amphiphilic funtionalites (ethoxylated mono-, di-, tri-, and tetraesters) were separated by HILIC mode of high-performance liquid chromatography (HPLC). All these separated functionaities are identified and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). This combination of HPLC and MALDI-TOF MS has been proven to be an excellent tool for the characterization of heterogenous complex samples.

Analysis of polyethyleneoxide macromonomers by liquid chromatography along the critical adsorption line.

Polyoxyethylene macromonomers are analyzed by one-dimensional liquid chromatography under different conditions, depending on the required information. These samples may contain polyethylene glycol (PEG) and the corresponding di(meth)acrylate besides the desired mono(meth)acrylate. The molar mass distribution (MMD) of the PEG and the monoester can be obtained by liquid adsorption chromatography (LAC) on a reversed-phase column in acetone-water with a gradient from 10% to 20% acetone. The MMD of the diesters can be obtained with isocratic elution by liquid chromatography at critical conditions (LCCC) on a reversed-phase column in 31% acetone, or using size-exclusion conditions for PEG and LAC conditions for the end groups, which is the case in 40-55% acetone. The absolute amount of the series with different functionality can be obtained by LCCC in ternary mobile phases consisting of acetone, methanol, and water along the critical adsorption line. Under such conditions, all series elute as narrow peaks (regardless their MMD), which can easily be integrated and quantified.

Characterization of polyoxyethylenes according to the number of hydroxy end groups by hydrophilic interaction chromatography at critical conditions for polyethylene glycol.

Polyoxyethylenes with different functionality and architecture can be separated according to the number of terminal hydroxy groups on polar stationary phases in acetone water mobile phases containing 90-97% acetone. The best results were obtained on a HILIC column. Typical samples, which can be analyzed by this technique, are polyethylene glycols, their mono- and dialkyl ethers, macromonomers, the fatty esters of PEG, and ethoxylated glycerol.

Separation of nonionic surfactants according to functionality by hydrophilic interaction chromatography and comprehensive two-dimensional liquid chromatography.

It is shown, that amphiphilic polymers--such as polysorbates and fatty esters of polyethylene glycol can be separated by comprehensive two-dimensional liquid chromatography using a reversed phase column (under critical conditions for the polyoxyethylene chain) and a HILIC column, which may arranged in different order. The mobile phases in both dimensions can be 93-97 wt% acetone water. As the retention of higher esters on the reversed phase column is very strong, this column should be used as the first dimension. On the HILIC column all fractions elute within a reasonably short time (at a flow rate of 2.5 ml/min within 2 min). With a flow rate of 0.1 ml/min in the first dimension, a full separation can be achieved in 90 min.