Phytochemical Analysis, Pharmacological Activities, Isolation and Characterization of Bioactive Compounds from the Roots of Sterculia urens Roxb.

The present study was intended to explore the pharmacological significance of the crude root extract of Sterculia urens Roxb. Further the bio-active compounds were isolated and characterized using chromatographic and spectroscopic techniques. Soxhlet extraction apparatus was utilized for isolation of the chemical constituents from the root using a series of solvents such as n-hexane, ethyl acetate, methanol and water. The pharmacological activities such as inhibition of DPPH radical, α-amylase enzyme activity, albumin denaturation along with antibacterial and thrombolytic activities. The isolation of purified bioactive constituents was carried using preparative HPLC technique and the purified compounds were characterized using spectroscopic techniques like NMR, IR and mass. Among the crude root extracts, methanolic extract shows high DPPH radical scavenging activity with IC50 concentration of 26.74 ± 0.08 μg/mL. The IC50 concentrations in α-amylase enzyme inhibition activity was 263.96 ± 0.90, 127.73 ± 1.23 and 223.54 ± 4.76 μg/mL, respectively for ethyl acetate, methanol and water extracts, respectively. The methanolic extract shows high albumin denaturation inhibition assay than other extracts with IC50 concentration as 137.09 ± 0.20 μg/mL, which is very close to standard ascorbic acid. The methanolic extract also shows high % clot lysis than other extracts and results were comparable with 100 μL of streptokinase standard. The preparative HPLC followed by spectral analysis confirm that two known alkaloids (Sterculinine I & II) and three known flavonoids (gossypetin, apigenin and 6-hydroxyluteolin) were purified and characterized from the root methanol of Sterculia urens Roxb. The purified and identified compounds were reported for the first time in Sterculia urens Roxb.

Effect of Different Acids on Rice Husk Calcination and Extraction of Bio-Silica

Silica is an essential material which has many applications in various fields such as construction, catalyst, optical fibers and raw material of metallurgical industry. This work observed the recent trends in silica extraction from agro and natural wastes for high-tech applications. Hence, this work approached in new way for the bio-silica extraction from waste rice husk using HCl, H2SO4 and CH3COOH for the calcination. The results revealed that the effect of pH on ash nature and silica purity. The purity of silica was differed based on metal ions, rice husk ash color and non-combusted carbon. The results were compared with treatment in absence of acid ash using FT-IR, SEM, EDAX and XRD analysis to measure the effect of pH on the bio-silica purity. This work observed the lower carbon content in acid treated ash when compare to water washed rice husk.

Synthesis and Deblocking Investigations of Phenol Blocked Aliphatic Isocyanates and Their Application in the Development of Epoxy-Polyurethane Films

Phenol blocked hexamethylenediisocyanate adducts and polyisocyanates were synthesized and their structure was validated by FTIR, 1H & 13C NMR spectroscopy, TGA, DSC and CO2 evolution techniques were used to evaluate the deblocking temperature of blocked isocyanates. Gel time studies of blocked isocyanates with terathane polyol and solubility study of blocked isocyanates with different polyols were conducted to demonstrate the structure-property correlation. Epoxy-polyurethane films were produced utilizing the blocked isocyanates reported in this work with epoxy resin and their structure was verified by ATR Spectroscopy. TGA, DSC, shore A hardness, tensile strength and flexural strength analysis were used to investigate the thermal and mechanical characteristics of these films. The findings of deblocking temperature and gel time revealed that unsubstituted phenol blocked isocyanates and polyisocyanates deblock at lower temperatures and cure for a shorter time period than substituted phenol blocked isocyanates. Thermal and mechanical characteristics of epoxy-polyurethane films based on blocked polyisocyanates are satisfactory.

Optical Absorption, Kinetics and Thermodynamic Studies of Pr(III) and Nd(III) Ions with N-Acetyl L-Cysteine in Presence of Ca(II) ions

Interaction of N-acetyl-L-cysteine (NAC) with Pr3+ (Pr(NO3)3·6H2O) and Nd3+ (Nd(NO3)3·6H2O) ions are studied in presence of Ca2+ (Ca(NO3)3·4H2O) ion in an aqueous and organic solvent by applying the spectroscopic technique for quantitative probe of 4f-4f transition. The complexation was determined by the variation in the intensities of 4f-4f absorption spectral bands and by applying the change of symmetric properties of electronic-dipole known as Judd-Ofelt parameters Tλ (λ = 2,4,6). On the addition of Ca2+ ion in the binary complexation of praseodymium and neodymium with N-acetyl-L-cysteine (NAC) there is an intensification of bands which shows the effect of Ca2+ toward the heterobimetallic complex formation. Other parameters like Slater-Condon (Fk), bonding (b1/2), the Nephelauxetic ratio (β), percentage covalency (δ) are also used to correlate the complexation of metals with N-acetyl-L-cysteine (NAC). With the minor change in coordination around Pr3+ and Nd3+ ions, the sensitivity of 4f-4f bands is detected and further used to explain the coordination of N-acetyl-L-cysteine (NAC) with Pr3+ and Nd3+ in presence of Ca2+. The variation in oscillator strength (Pobs), energy (Eobs) and dipole intensity parameter help in supporting the heterobimetallic complexation of N-acetyl-L-cysteine. In kinetics investigation, the rate of the complexation of both hypersensitive and pseudo-hypersensitive transition is evaluated at various temperature in DMF solvent. The value of the thermodynamic parameters such as ΔHo, ΔSo and ΔGo and activation energy (Ea) also evaluated.

Facile Green Synthesis and Characterization of Titanium Dioxide Nanoparticles Using Kigelia africana (Lam) Benth., Aqueous Leaf Extract and its Antioxidant and Antibacterial Activity

Titanium nanoparticles are toxic to bacteria and have a widespread applications in different fields of research. Hence the present study aimed to synthesize the titanium dioxide nanoparticles by adopting green synthesis methodology using Kigelia africana leave extract as a biological reducing agent. The UV absorption spectra show characteristic absorption maxima corresponding to TiO2 nanoparticles at a wavelength of 512 nm confirms the formation of nanosized tin particles. The FT-IR spectrum of TiO2 nanoparticles show absorption bands at 3609 cm-1 and 3227 cm-1 corresponding to O-H stretching in alcoholic and carboxylic compounds, respectively. Absorption peaks at 1607, 2834, 1654 and 1324 cm-1 correspond to aromatic C=C vibrations, C-H stretching in aldehydes, C-H bending vibrations and aromatic C-N stretching vibrations, respectively. This confirms the involvement of bioactive compounds from the plant extract. The SEM and EDX studies confirmed that the nanoparticles are spherical to oval shape with an average particle size of 46 nm. The metal content in the nanoparticles was found to be 58.71%. The synthesized nanoparticles have potential growth inhibition activity against Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). The DPPH radical scavenging activity of the nanoparticles synthesized was compared with that of aqueous leaf extract and standard ascorbic acid and proved that the nanoparticles have enhanced activity than aqueous leaf extract. The IC50 of the leaf extract, nanoparticles and the standard was found to be 31.55, 75.82 and 84.95 μg/mL, respectively. Kigelia africana leaf is shown in this work to be a valuable bioagent in the biosynthesis of TiO2 nanoparticles with increased biological activity.

Quasi Emulsion Solvent Diffusion Modification of Underutilized Chenopodium album Starch and its Characterization

The present study was designed to investigate the changes occur on Chenopodium album starch (CAS) after modification through quasi emulsion solvent diffusion (QESD) method. Modification of starch was carried out by HCl (0.1, 0.25, 0.50, 0.75 and 1M) followed by precipitation. The QESD modification significantly reduced the amylose content, water absorption capacity, oil absorption capacity, solubility as well as swelling power of treated starch. Gelatinization behaviour of modified starch showed an increase in pasting temperature. The SEM images showed the formation of regular and spherical shaped larger starch particles. There was an improvement in crystallinity from 20.01 to 29.86% after modification as shown in X-ray analysis. Overall, it indicates that QESD treatment results into formation of spherical crystalline agglomerates.

Determination of 3-Monochloropropanediol and Glycidol in Food Products

Due to the increasing globalization of food markets, there are evolving new challenges for maintaing food safety. The current problem is the development of analytical methods for 3-monochloropropanediol ester and glycidol ester, which are food contaminants of concern for the scientific community. The levels of 3-monochloropropanediol ester and glycidol ester in certain food products are controlled by the European legislation. However, the maximum allowed concentrations and uptake limits for various food products are permanently revised. Therefore, we aimed to determine 3-monochloropropanediol ester and glycidol ester in various food products, which may contain vegetable oils. We analyzed food samples obtained from local food shops, predominantly low-priced products, which are more likely to contain vegetable oils, and adulterated milk fat. The levels of 3-monochloropropanediol ester and glycidol ester were determined indirectly by analyzing free 3-monochloropropanediol and glycidol ester obtained by hydrolysis and derivatized with phenylboronic acid. Samples were analyzed by GC-MS/MS on a triple-quad mass spectrometer.

Production of Bacterial Cellulose by Acetobacter tropicalis Isolated from Decaying Apple Waste

Fruits and vegetables have the highest wastage rates of 45% of any food. One of the recent research areas is food waste valorization as a potential alternative to the disposal of a wide range of organic waste using microorganisms as one of the strategies known as microbial valorization. Bacterial cellulose is best known microbial valorization product because of its low cost, environmentally friendly nature, renewability, nanoscale dimensions, biocompatibility and extremely high hydrophilicity. Therefore, present study focuses on the isolation, characterization and identification of cellulose producing bacteria from decaying apple waste. Cellulose producers were isolated from decaying apple waste. The bacterial isolates obtained were identified through the morphological biochemical, physiological and molecular identification. The bacterial isolates exhibited potential remediation options to biovalorize decaying fruit waste by producing value added products as well as in safe disposal of waste.

Photocatalytic Degradation of Rhodamine B and Malachite Green by Cobalt Sulfide Nanoparticles

Present study reports the simple and cost effective thermolytic method for the synthesis of cobalt sulphide nanoparticles (CoS NPs). The PXRD spectrum of cobalt sulphide (CdS) nanoparticles exhibited four peaks indexed to (100), (101), (102) and (110) crystal planes. The average particle size observed from DLS and PXRD was in the range 4.81-12.20 nm. A blue shift in band gap was observed from UV-visible spectra. The FESEM and TEM studies revealed that cobalt sulfide nanoparticles are of cubic and rectangle shapes. FTIR spectra of hexadecylamine (HDA) capped CoS NPs exhibited ν(N-H) absorption around 3350-3240 cm–1. The stretching frequency due to ν(Co-S) appeared in the region 334-332 cm–1. Proton NMR (1H) spectra of CoS NPs showed signals at nearly same positions as in case of capping agent, suggesting its capping nature. ESI-MS analyses of cobalt sulphide nanoparticles displayed peak at m/z = 124.93 corresponding to the [CoS2]+ ion. Thermogravimetric curves showed single step decomposition corresponding to 84.28% weight loss and 15.72% as final residue due to cobalt oxide. The degradation rate of rhodamine B and malachite green dyes after irradiating with sunlight showed 92-94% degradation while irradiated with UV-light of 4.8 eV show much slower degradation rate.

In silico, ADMET and Docking Analysis for the Compounds of Chloroform Extract of Tinospora cardifolia (Wild.) Identified by GC-MS and Spectral Analysis for Antidiabetic and Anti-Inflammatory Activity

The present study was aimed to phytochemical and GC-MS analysis for chloroform extract of Tinospora cardifolia. The structure of the compounds was further confirmed by UV-spectroscopy and FTIR study. The in silico study like molecular, physico-chemical and drug likeliness property was carried out by computational approaches for the identified molecules. Further toxicity potential and pharmacokinetic profile were also determined. The study was carried out using OSIRIS data warrior and Swiss ADME tools. The docking analysis was carried out for the antidiabetic and anti-inflammatory profiles. The compounds were targeted for α-glucosidase, peroxisome proliferator-activated receptor, glucose transporter-1, cyclo-oxygenase-1 & 2 inhibitions. There were around 12 compounds identified by GC-MS analysis. All the compounds exhibited moderate to good drug likeliness and pharmacokinetic potentials. The molecules showed a good bioactivity score against enzyme receptors. The ADMET prediction showed PGP and CYP-inhibitory effects with the least toxic profile. The docking analysis showed strong binding affinity of [1S-(1α,3aα,4α,6aα)]-1H,3H-furo[3,4-c]furan tetrahydrophenyl (molecule-7) on targeted proteins under investigation.