Showing papers in "Asian Journal of Chemistry in 2020"
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TL;DR: In this paper, the extraction of essential oils from the peels of pomelo (Citrus grandis L.) grown in Ben Tre province, Vietnam through hydrodistillation method was reported.
Abstract: This study attempted the extraction of essential oils from the peels of pomelo (Citrus grandis L.)
grown in Ben Tre province, Vietnam through hydrodistillation method. In addition, the chemical
composition and physio-chemical properties of the essential oils were reported. The results showed
that the extraction yield of the extraction process achieved about 1.67%. The physico-chemical index
of essential oils is determined by specific gravity (0.8572 g/cm3), acid index (0.3556 mg KOH/g),
ester index (2.4216 mg KOH/g), and refractive index (1.476). The GC-MS analyses of the oil indicated
the component with highest content in the oil was α-limonene (96.491%), followed by α-pinene
(0.686%), β-pinene (0.248%), β-myrcene (1.644%), α-phellandrene (0.793%) and β-cis-ocimene
(0.138%). These results suggested that wastes from fruit peeling process can be converted into a new
material source with great potential for industrial use.
19 citations
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TL;DR: In this article, a study on kinetics and modeling of the essential oil steam distillation are required for the optimization of the energy requirement, parameters and the process scale-up.
Abstract: Study on kinetics and modeling of the essential oil steam distillation are required for the optimization
of the energy requirement, parameters and the process scale-up. In this study, hydrodistillation for
extraction of essential oils from lemongrass (Cymbopogon citratus) steam distillation was investigated.
The recovery of essential oils was carried out on an industrial scale instrument and with with different
material quantities. The experimental results are determined by the integral method of analysis. The
kinetic parameters were evaluated from experimental data, which were generated at the different weights
of the lemongrass. The extraction rate constant explaining the extraction efficiency achieved from this
study is found to be k2 of 0.0661 min-1 in 710 kg using a second-order kinetic model. The GC/MS results
revealed that 14 components were identified in Cymbopogon citratusoils. The oil is extremely rich in
citral (69.775%), which obtained in 180 min.
14 citations
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TL;DR: In this article, an analysis of Eucalyptus camaldulensis leaves was carried out to identify phytochemicals and evaluate antioxidant activities of different extracts from the plant in the Myrtaceace family.
Abstract: This study aimed to identify phytochemicals and evaluate antioxidant activities of different extracts
from Eucalyptus camaldulensis, an aromatic plant in the Myrtaceace family. Examined extracts in
different solvents such as diethyl ether extract (DEE), the ethanolic extract (EE) and the aqueous
extract (AE). Total polyphenol and total flavonoid contents were determined via aluminum chloride
colorimetric method. Antioxidant activity was performed via ABTS and DPPH radical scavenging
assays. The results showed that a wide variety of pharmacologically active compounds such as alkaloid,
oil, flavonoid, triterpenoid, saponin, tannin and polyphenol were present in the leaves of Eucalyptus
camaldulensis. The result of quantitative determination showed that total polyphenol content of the
diethyl ether extract, ethanolic extract and aqueous extract achieved 73.47 ± 1.64, 306.48 ± 3.87 and
76.47 ± 1.64 mgGAE/g, respectively. Meanwhile, total flavonoid content was 41.74 ± 2.21, 45.98 ±
1.79 and 18.05 ± 0.81 mgQE/g, respectively. The ethanolic extract exhibited the highest DPPH (IC50
= 10.52 ± 0.14 μg/mL) and ABTS (IC50 = 9.86 ± 0.17 μg/mL). These results indicate that Eucalyptus
camaldulensis leaves can be used in dietary applications with the potential to reduce oxidative stress.
13 citations
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TL;DR: Sacha inchi (Plukenetia volubilis L.) seed oil was studied for physico-chemical characteristics and chemical composition as mentioned in this paper, revealing that the oil is rich in linoleic acid (42.62 %), linolenic acid(36.32 %) and oleic acid
Abstract: Sacha inchi (Plukenetia volubilis L.) seed oil was studied for physico-chemical characteristics and chemical composition. Through gas chromatography-flame ionization (GC-FID) process, the fatty acid composition in the oil was analyzed, revealing that the oil is rich in linoleic acid (42.62 %), linolenic acid (36.32 %) and oleic acid (11.64 %). The tocopherol level in the oil was also high (7.7 ± 0.005 mg/Kg), revealed by high-performance liquid chromatography/ultraviolet-visible detector (HPLC/UV-VIS). The physico-chemical properties of the oil were also examined, including viscosity (88-92 cP), acid value (2.05 ± 0.005 mg KOH/g), saponification content (183.5 ± 1.45 mg KOH/g)
and iodine value (192.4 ± 1.55 g I2/100 g). The results also indicated that sacha inchi is a health beneficial oil due to the high contents of essential fatty acids (ω-3, ω-6 and ω-9).
10 citations
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TL;DR: In this paper, a D-optimal design was used as an RSM tool to acquire the maximum response value, which was in a excellent agreement with the values predicted using a regression model.
Abstract: In the presence of a catalyst, p-toluenesulfonic acid (PTSA), the ring of epoxidized palm oil (EPO)
was opened using oleic acid (OA). The optimization effects of different process variables including
the mol ratio of EPO/OA, reaction temperature, PTSA percentage and reaction time was performed by
response surface methodology (RSM). To assess the effects of process variables and interactions among
them, a D-optimal design was used as an RSM tool to acquire the maximum response value. The following
are the optimum conditions achieved at the reaction time of 4.73 h in the RSM study: 1.02% PTSA, 3
EPO/OA mol ratio and 119.14 ºC reaction temperature. These conditions resulted in 84% yield, 0.041%
oxirane oxygen content (OOC), 59.4 mg/g iodine value (IV), and118.7 mg/g hydroxyl value (HV). The
results are in a excellent agreement with the values predicted using a regression model.
10 citations
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TL;DR: In this article, the authors attempted the optimization of the extraction process involving essential oils from Vietnamese pomelo fruits and established a statistical model to investigate three influential parameters including ratio of water and material, extraction time, and temperature.
Abstract: This study attempted the optimization of the extraction process involving essential oils from Vietnamese pomelo fruits. Three influential parameters including ratio of water and material, extraction time, and temperature were assumed to be impactful to the oil yield and were investigated by establishing a statistical model. A central composite design was adopted to generate dataset required for estimation of the model. Analysis of variance was used to calculate model significance. The results showed that optimum yield of pomelo oil is 4.46 % (v/w) corresponding to water ratio of 507 mL water to 100 g
sample, temperature at 119.29 ºC and distillation time of 113.68 min. Predicted values proposed by the Design Expert 11 software well-agreed with the empirical data, suggesting the excellent predictability of the proposed models. In addition, the essential oil obtained under optimal conditions was analyzed by gas chromatography-mass spectrometry. The results indicated that D-limonene is the main component
(97.318 %) of essential oil.
10 citations
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TL;DR: In this paper, the essential oil of lemongrass was obtained using hydrodistillation method and evaluated for chemical compositions and physico-chemical characteristics, including specific gravity (0.8865 g/cm3), acid index (2.948), ester index (6.402), and refractive index (9.35).
Abstract: The lemongrass (Cymbopogon citratus L.) essential oil plays a vital role as an ingredient in different
fields due to aromatic, antibacterial properties and antifungal activity. In this study, essential oil of
lemongrass was obtained using hydrodistillation method and evaluated for chemical compositions
and physico-chemical characteristics. The averaged physico-chemical parameters were determined as
specific gravity (0.8865 g/cm3), acid index (2.948), ester index (6.402) and refractive index (9.35).
Moreover, the hydrodistillation process performance was achieved 0.29%. The composition of essential
oils was analyzed by GC-MS, revealing a total of 18 volatile constituents existing in the lemongrass
oil. The major components were α-citral (40.838%), β-citral (28.494%), β-myrcene (16.654%),
2,3-dehydro-1,8-cineole (2.264%) and geraniol (2.388%). The citral component accounts for high
content (more than 70% of volume) of oil.
9 citations
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TL;DR: In this paper, a series of (S)-(−)-nicotinium salts of cyclic dithiophosphoric acids were synthesized by the reactions of 5,5-dimethyl-2-mercapto-2 -thiono-1,3,2-dioxaphosphorinane and 4-methyl- 2-merCapto- 2 -th iono- 1, 3,2 -dioxamide with (S −)-( −)-nicotine.
Abstract: A new series of (S)-(–)-nicotinium salts of cyclic dithiophosphoric acids were synthesized by the reactions of 5,5-dimethyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane and 4-methyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane with (S)-(–)-nicotine. Picolinic and nicotinic acids and potassium pyridine-3-carboxylate reacted with O,O-diterpenyl dithiophosphoric acids on
the basis of (1R)-endo-(+)-fenchyl alcohol and (S)-(–)-menthol to afford the corresponding 2-carboxypyridinium, 3-carboxypyridinium and potassium pyridinium-3-carboxylate dithiophosphates. The antibacterial and antifungal activity of (S)-(–)-nicotinium 4-methyl-2-mercapto-2-thiono-1,3,2- dioxaphosphorinane and salts of O,O-diterpenyl dithiophosphoric acids on the basis of nicotine and nicotinamide were evaluated.
8 citations
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TL;DR: The cytotoxicity of bio-originated selenium nanoparticles was tested under in vitro conditions on Vero cell line and compared with MDA-MB231 cancer cell line at different concentrations and the results had proved that bio- Originated synthesis selenum nanoparticles can inhibit the growth of human breast-cancer cells by concentration-dependent manner.
Abstract: Present work describes the bio-originated synthesis of selenium nanoparticles using seed extract of Cassia angustifolia. The biological macromolecules in seed extract react with metal ions to generate selenium nanoparticles. The seed extract acts as reducing, capping and stabilizing agents. The selenium nanoparticles produced by the plant extract are amorphous, nearly spherical in shape and held together by protein coating in a range of about 80-100 nm in size, under ambient conditions. The structural
properties of selenium nanoparticles were characterized by UV-visible spectroscopy, FTIR, XRD, FESEM with EDAX, HRTEM and AFM. Antibacterial and antifungal activity of selenium nanoparticles were tested against four bacterial and two fungal strains using standard agar-well diffusion method. The zone of inhibition was observed in the selenium nanoparticles against different microbes and suggested that the bio-originated selenium nanoparticles act as an effective antibacterial and antifungal
agent, so it has a great latent in the preparation of drugs used against pathogenic diseases. The cytotoxicity of bio-originated selenium nanoparticles was tested under in vitro conditions on Vero cell line and had compared with MDA-MB231 cancer cell line at different concentrations and the results had proved that bio-originated synthesis selenium nanoparticles can inhibit the growth of human breast-cancer cells by concentration-dependent manner.
8 citations
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TL;DR: In this paper, the authors synthesize zeolites impregnated with Ni through wet impregnation using activated NZs and the nickel nitrate hexahydrate (Ni(NO3)2·6H2O) precursor.
Abstract: Zeolites impregnated with Ni were successfully synthesized through wet impregnation using activated
natural zeolites (ANZs) and the nickel nitrate hexahydrate (Ni(NO3)2·6H2O) precursor at different
concentrations of 1%, 2% and 3% (w/w) (hereafter referred to as ANZ/Ni 1%, ANZ/Ni 2%, and
ANZ/Ni 3%). The synthesized products were characterized using X-ray diffraction (XRD), Fourier
transform infrared spectroscopy (FTIR), surface area analyzer (SAA), scanning electron microscopy
(SEM), total acidity measurements by employing ammonia adsorption and Brunauer-Emmett-Teller
(BET) theory. The obtained catalysts were employed in the hydrocracking of waste cooking oils, and
the formed products were analyzed through gas chromatography-mass spectrometry (GC-MS). The
FTIR results indicated that ANZs impregnated with Ni can increase zeolite acidity. The test results of
total acidity revealed that 3% ANZ/Ni catalyst exhibited the maximum total acidity of 3.70 mmol/g.
XRD diffractogram confirmed the successful impregnation of Ni into ANZs, which was indicated by
the characteristic diffraction peaks appearing at 2θ of 9.75º, 13.41º, 19.56º, 22.25º, 25.61º, 27.66º and
31.91º. SEM analysis indicated that the particle size of zeolite catalysts was non-uniform, but these
catalysts exhibited a highly uniform surface after they were activated. Moreover, the ANZ catalysts
impregnated with different concentrations of Ni exhibited a highly uniform particle size. The ANZ/Ni
3% catalyst had small uniform particle. The BET results revealed that the ANZ/Ni 2% catalyst exhibited
the maximum pore volume and surface area and relatively smaller radii of pores. GC-MS was employed
to determine liquid products, and its results showed that the ANZ/Ni 3% catalyst had the maximum
amount of liquid products of 18%.
8 citations
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TL;DR: In this article, a triazine-based organic molecules were synthesized by using cyanuric chloride and 2,4-dichloro-1-ene(4-hydroxyphenyl)phenone and characterized by elemental analysis, FT-IR, NMR and UV-visible spectrometry techniques.
Abstract: In this work, we have synthesized efficient antibacterial compounds with anticancer novel molecules based on cyanuric chloride containing chalcone moiety. For this, novel triazine-based organic molecules were synthesized by using cyanuric chloride and 2,4-dichloro-1-ene(4-hydroxyphenyl)phenone and characterized by elemental analysis, FT-IR, NMR and UV-visible spectrometry techniques. Melting point of the molecules were increased with an increase in substitution on cyanuric chloride. The minimum inhibitory concentration (MIC) value of the synthesized compounds showed an excellent
result on Gram-negative bacteria with low MIC value of 1.95 μg/mL. Gram-positive bacteria showed little resistance to the synthesized drug. The synthesized compounds were tested for their use as an anticancer drug using in silico screening method. The synthesized compounds in silico molecular docking method using breast cancer protein (BRCA2) confirms that triazine derivative with all three chlorine molecules replaced by 2,4-dichloro-1-ene(4-hydroxyphenyl)phenone showed highest binding
energy with the value of -9.1900 Kcal/mol which is in agreement with the observed high MIC value obtained for Gram-negative bacteria. The synthesized molecules preferentially targeted the topoisomerase II of the bacteria. Overall, an efficient antimicrobial drug is synthesized using a simple preparation method.
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TL;DR: In this article, the use of deep eutectic solvents (DESs) for enzymatic biodiesel production from degumming palm oil (DPO) was investigated.
Abstract: Deep eutectic solvents (DESs) have numerous potential applications as cosolvents. In this study, use of DES as organic solvents for enzymatic biodiesel production from degumming palm oil (DPO) was investigated. Deep eutectic solvent was synthesized using choline chloride salt (ChCl) compounds with glycerol and 1,2-propanediol. Deep eutectic solvent was characterized by viscosity, density, pH and freezing values, which were tested for effectiveness by enzymatic reactions for the production of palm biodiesel with raw materials DPO. Deep eutectic solvent of ChCl and glycerol produced the highest biodiesel yield (98.98%); weight of DES was only 0.5 % of that of the oil. In addition, the use of DES maintained the activity and stability of novozym enzymes, which was assessed as the yield until the 6th usage, which was 95.07 % biodiesel yield compared with the yield without using DES. Hence, using DES, glycerol in enzymatic biodiesel production had high potentiality as an organic solvent for palm oil biodiesel production
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TL;DR: One-pot, multicomponent H2O2-HCl catalyzed system was employed for the synthesis of a series of benzazepine compounds as discussed by the authors, which oxidized the carbon-nitrogen bonds and produced Benzazenines, while integrating diamines and substituted ketone.
Abstract: One-pot, multicomponent H2O2-HCl catalyzed system was employed for the synthesis of a series of
benzazepine compounds. The implemented procedure oxidized the carbon-nitrogen bonds and produced
benzazepines, while integrating diamines and substituted ketone. The advantage of the exercised
synthetic route was that the reaction was water mediated and the completion time was quite reduced
compared to the time required by conventional methods
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TL;DR: In this paper, the adsorbents were characterized by SEM, XRD, FTIR, TGA and BET, and the equilibrium data fitted Langmuir isotherm
model for CBC, ACBC10 and ACBC-20 with r2 of 0.994 to 0.997.
Abstract: Carbon from black cumin seeds was modified with 10 and 20% sulfuric acid to obtain the activated
adsorbents. Pristine carbon from black cumin seeds, 10 and 20% H2SO4 activated carbon from black
cumin seeds were labelled CBC, ACBC-10 and ACBC-20, respectively. The adsorbents were
characterized by SEM, XRD, FTIR, TGA and BET. The adsorbents maximum trend for Cd(II) was
ACBC-10 > ACBC-20 > CBC. The maximum capacity trend for methylene blue dye was ACBC-20 >
ACBC-10 > CBC. The kinetic model best fitted pseudo second order for Cd(II) which gave r2 values
of 0.991-0.998. The methylene blue fitted pseudo first order model with r2 values ranging from
0.993-0.997. Pseudo first order suggested that the adsorption mechanism for methylene blue onto
adsorbents involved van der Waal forces of attraction. The equilibrium data fitted Langmuir isotherm
model for CBC, ACBC-10 and ACBC-20 with r2 of 0.994 to 0.998 for the removal of methylene blue
whilst the removal of Cd(II) followed Freundlich with r2 ranging from 0.992 to 0.997. This suggested
that the different adsorption processes were involved between the adsorbate and the adsorbents. Gibb′s
free energy (ΔGº) for Cd(II) and methylene blue onto CBC, ACBC-10 and ACBC-20 suggested that
the reaction was spontaneous. The adsorption of Cd(II) and methylene blue was endothermic, positive
values (ΔHº). This suggested that the enthalpy (ΔHº) had a weak interactive force process whose low
energy is associated with electrostatic attraction.
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TL;DR: In this article, the synthesis of lanthanum doped strontium titanate (Sr1-xLaxTiO3,x=0.1) by solgel method was reported.
Abstract: We report the synthesis of lanthanum doped strontium titanate (Sr1-xLaxTiO3,x=0.1) by sol-gel method.
The physical properties of the as-synthesized sample were systematically studied through X-ray powder
diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM)
and energy dispersive X-ray spectroscopy (EDAX). Diffraction peaks in XRD supported the cubic
formation of perovskite-type crystal structure. The image analysis of nanomaterial by SEM and TEM
techniques disclosed aggregates of nanoparticles with grain size about 20 nm. The study by UV-DRS
exposed the band energy gaps (Eg) of 3.4 eV for strontium titanate nanoparticles, respectively. The
degradation studies for three days were carried out for three dyes. Malachite green and rhodamine
blue, strontium titanate nanoparticles showed utmost photocatalytic activity for rhodamine blue under
UV light irradiation (from 0 to 80 min) as compared to malachite green. Properties of electrochemistry
were looked into by cyclic voltammetry and galvanostatic charge/discharge in 1M KCl electrolyte.
The Sr0.9La0.1TiO3 electrode displayed maximal specific capacitance of 306.74 F g-1 at current 1mA
from galvanostatic charge-discharge curve. The rare earth doped perovskite Sr0.9La0.1TiO3 nanomaterial
exhibited increased surface area with superior supercapacitance property.
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TL;DR: In this paper, a study using DPPH and ABTS method to detect the maximum active ingredients in tea simultaneously was conducted and the results showed that the antioxidant activity of the ethanol extract of Soursop was correlated with total phenolic and flavonoid content.
Abstract: Tea is the most commonly consumed beverage worldwide due to promote health and prevention of
some human diseases. Soursop tea pulp is one of a new product focused on the values of total ascorbic
acid (TAA), total polyphenol content (TPC) and total flavonoid content (TFC). A study using DPPH
and ABTS method to detect the maximum of active ingredients in tea simultaneously. Different pulp
tea samples with varying dates of production checked for TAA, TPC, TFC, antioxidation and sensory
evaluation. There is a difference in TAA between sample (1) and (4), achieved 7.43 ± 0.04 mg/g DM
and 12.21 ± 0.04 mg/g DM, respectively. TFC content ranged between 0.13 and 0.18. The phenolics
group in tea is high and there are differences between the 3 recent production samples with (1): 3.81
mg QC/g DM fluctuation. In sample 1, the antioxidant activity of the ethanol extract of Soursop was
correlated with total phenolic and flavonoid content with values IC50 of 0.26 mgAA/g DM, 2.61 mgAA/g
DM for DPPH and ABTS scavenging activity, respectively. Moreover, the Lab* colour space of the
soursop tea is measured in the dark area, the L* difference achieved at 30.82 ± 1.24 (2) lowest and the
highest 37.42 ± 4.77 (1). Consumer sensory evaluation is performed with results based on a 5-point
scale describing: flavour, aroma, colour and favourite.
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TL;DR: In this paper, a hybrid composite of VIV+PMo11O40 and β-CD was proposed to characterize lung cancer A549 cell line using techniques such as FT-IR, EPR, SEM, EDS and X-ray diffraction.
Abstract: A novel hybrid composite, namely {[VIV+PMo11O40]⊂[β-CD]} which shows the high percent of apoptosis of MTT assay of A549 cell line (lung cancer) in different concentrations. The composite has been characterized using techniques such as FT-IR, EPR, SEM, EDS and X-ray diffraction. The anticancer (lung cancer A549 cell line) was investigated using direct microscopic observations for drug treated cell line and IC50 value of 1.93. The apoptosis of 45.37 % cell death in cell line of minimum concentration (3.12 μg/mL) shows the good viability of β-CD-POM against lung cancer A549 cell
line.
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TL;DR: In this article, the essential oil extracted from the peel of Solanum incanum was analyzed by GC-MS (gas chromatography-mass spectrometry) and 17 compounds including 2,3-butanediol (76.76%), diethyl phthalate (8.32%), benzyl benzoate (3.02%), 2,6-dimethyl-6-nitro-2-hepten-4-one (2.56%), and 1,2-dimethoxy-1-propenyl)benzene
Abstract: Phytochemicals were extracted from the peel of Solanum incanum (S. incanum) with methanol (70%
v/v). The phytochemical screening of the methanolic extract showed the presence of glycosides, steroids,
terpenoids, flavonoids, tannins, alkaloids, saponins and phenolic compounds. The successive
partitioning of the methanolic extract was carried out with three solvents hexane, diethyl ether and
ethyl acetate. The diethyl ether fraction yielded two immiscible fractions. The oil was separated as
essential oil fraction and analyzed by GC-MS (gas chromatography-mass spectrometry). The GC-MS
analysis of the essential oil indicated 17 compounds including 2,3-butanediol (76.76%), diethyl phthalate
(8.32%), benzyl benzoate (3.02%), 2,6-dimethyl-6-nitro-2-hepten-4-one (2.56%) and 1,2-dimethoxy-
4-(1-propenyl)benzene (1.88%). Among them, the mass spectral patterns of three compounds were
analyzed, discussed and confirmed with NIST database. The antibacterial study of essential oil was
conducted using four pathogens (E. coli, K. pneumonia, S. aureus and S. pyogenes) at four different
concentrations (250, 500, 750 and 1000 μg/mL). The result indicates that the essential oil extracted
from the peel of Solanum incanum exhibited remarkable antibacterial activity against E. coli and K.
pneumonia in 1000 μg/mL, respectively compared with the positive control gentamicin (10 μg/mL).
The result of this study revealed the presence of various organic components and the antibacterial
activity of this plant essential oil may be as a result of the major compounds.
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TL;DR: In this article, two coordination polymers of the general formula [Fe(BDC)(AMTZ)Cl]·2H2O and [Fe[BDC(MBT)]·H 2O, BDC = 1,4-benzenedicarboxylic acid, AMTZ = 2-amino-4-methyl-thiazole and MBT = 2mercaptobenzothiazole, have been synthesized.
Abstract: Two of coordination polymers of the general formula [Fe(BDC)(AMTZ)Cl]·2H2O and
[Fe(BDC)(MBT)Cl]·H2O, BDC = 1,4-benzenedicarboxylic acid, AMTZ = 2-amino-4-methyl-thiazole
and MBT = 2-mercaptobenzothiazole, have been synthesized and characterized. Structure of both
coordination polymers has been evaluated on the basis of elemental analysis, thermal, FT-IR, UV-vis
spectra and the charges been carried by the atoms, caused a dipole moment of 2.4346 debye and total
energy -382 × 103 Kcal mol-1. Biological activity of the two synthesized complexes was tested against
some fungal and bacterial strains
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TL;DR: In this paper, Dimocarpus longan leaves were used to extract chitosan nanoparticles (CSNPs) against periodontitis triggering bacteria using agar well diffusion method and the CSNPs were formed using DLLAE when the colour changed from white to pale brown.
Abstract: Present study was intended to synthesize and evaluate the Dimocarpus longan leaves aqueous extract
(DLLAE) based chitosan nanoparticles (CSNPs) against periodontitis triggering bacteria. In present
study the DLLAE was prepared by extracting D. Longan leaves in distilled water using decoction
method. The prepared DLLAE was subjected to phytochemical investigations, total phenolic content,
total flavonoid content study and CSNPs synthesis. The CSNPs were characterized (using UV-visible,
FT-IR, SEM, FESEM, XRD and EDX) and evaluated for their potential against periodontitis triggering
bacteria (using agar well diffusion method). The phytochemical investigations over DLLAE exhibited
presence of monosaccharides, reducing sugars, proteins, steroids, anthraquinones and coumarins
glycosides, flavonoids, alkaloids, organic acid, tannic and phenolic compounds. The CSNPs were
formed using DLLAE when the colour changed from white to pale brown. Absorbance of the CSNPs
was in the desired range (201-310 nm). The optimization study revealed 1% acetic acid, 1% sodium
alginate, 2 mg/mL chitosan, pH 5.8 and 1 mL DLLAE as the standard requirement for CSNPs synthesis
using DLLAE. The CSNPs characterization data of FT-IR exhibited shifted bands. The FESEM revealed
that the synthesized CSNPs were spherical in shape and their size ranged from 74.66 to 94.07 nm. The
XRD data showed peaks at 2θ values of 22.28º, 25.19º, 34.72º, 40.0º, 71.16º and 73.0º. The average
size for CSNPs was between 30.11-62.98 nm. The EDX spectrum revealed signal for carbon (76.17%),
oxygen (22.14%) and sodium (1.53%) which confirmed formation of CSNPs. The antibacterial activity
revealed high inhibitory potential of green CSNPs against S. aureus. Present studies establish that
CSNPs biosynthesis using D. longan leaves aqueous extract is an efficient method and the
biosynthesized CSNPs possess high antibacterial potential against S. aureus (bacteria that triggers
periodontitis).
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TL;DR: In this article, the effect of surfactant medium on the kinetics of oxidation of amino alcohol by cerium(IV) has been reported and a plausible mechanism for micellar catalysis has been presented.
Abstract: Effect of surfactant medium on the kinetics of oxidation of amino alcohol by cerium(IV) has been reported. Two amino alcohols namely,
monoethanolamine (MEA) and triethanolamine (TEA) are chosen for kinetic study. Sizeable changes in reaction rate are noted only in
presence of sodium lauryl sulphate (NaLS) as surfactant. Both the amino alcohols exhibit rate maxima at around the cmc of NaLS, beyond
which the kψ-[NaLS] profile shows slow increase in rate constant with increasing NaLS concentration. Suitable model has been used to
explain the kinetic pattern post CMC and from this the micelle-reactant binding constant values have been evaluated. From the temperature
dependence study, the activation parameters for the oxidation reactions have been computed and these are compared against those obtained
for aqueous medium. Based on all information, plausible mechanism for micellar catalysis has been presented.
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TL;DR: In this paper, a new series of organotin (IV) and organosilicon(IV) complexes were synthesized using the Schiff base ligands [2-((3,4-dimethoxybenzylidene)amino)-3-(1H-indol-3-yl)propanoic acid (L1H) and
Abstract: A new series of organotin(IV) and organosilicon(IV) complexes were synthesized using the Schiff
base ligands [2-((3,4-dimethoxybenzylidene)amino)-3-(1H-indol-3-yl)propanoic acid (L1H) and
2-((3,4-dimethoxybenzylidene)amino)-3-methylbutanoic acid (L2H)]. The synthesized compounds were
characterized by IR, NMR (1H and13C), elemental analysis and theoretical studies. The molar
conductivity values of the complexes in DMF implied the presence of non-electrolyte species. Spectral
data showed that in these complexes the metal atoms are coordinated with the Schiff base ligand acts
as a bidentate ON moiety, coordinating to the metal through its carboxylate oxygen and imine nitrogen.
The IR spectra of the complexes showed large differences between νasy(COO) and νsy(COO), Δν
(νasy(COO)–νsy(COO)) of 260-276 cm–1, indicating monodentate nature of the carboxylate group.
Furthermore, the density functional theory (DFT) calculations were executed at the B3LYP/6-31G(d,p)/
LanL2DZ basis set of theory for the optimized geometry of Schiff base complexes. The structural
parameters, bond length, bond angles, chemical potential, electronegativity, hardness, softness, global
electrophilicity index have been studied theoretically by density functional theory (DFT) to support
the experimental results.
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TL;DR: In this paper, the thermal decomposition behavior and kinetics of proteins, carbohydrates and lipids are studied by use of models derived from mass-loss data obtained from thermogravimetric analysis of Scenedesmus microalgae.
Abstract: In present work, the thermal decomposition behaviour and kinetics of proteins, carbohydrates and lipids is studied by use of models
derived from mass-loss data obtained from thermogravimetric analysis of Scenedesmus microalgae. The experimental results together
with known decomposition temperature range values obtained from various literature were used in a deconvolution technique to model
the thermal decomposition of proteins, carbohydrates and lipids. The models fitted well (R2 > 0.99) and revealed that the proteins have the
highest reactivity followed by lipids and carbohydrates. Generally, the decomposition kinetics fitted well with the Coats-Redfern first and
second order kinetics as evidenced by the high coefficients of determination (R2 > 0.9). For the experimental conditions used in this work
(i.e. high heating rates), the thermal decomposition of protein follows second order kinetics with an activation energy in the range of
225.3-255.6 kJ/mol. The thermal decomposition of carbohydrate also follows second order kinetics with an activation energy in the range
of 87.2-101.1 kJ/mol. The thermal decomposition of lipid follows first order kinetics with an activation energy in the range of 45-64.8 kJ/
mol. This work shows that the thermal decomposition kinetics of proteins, carbohydrates and lipids can be performed without the need of
experimentally isolating the individual components from the bulk material. Furthermore, it was shown that at high heating rates, the
decomposition temperatures of the individual components overlap resulting in some interactions that have a synergistic effect on the
thermal reactivity of carbohydrates and lipids.
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TL;DR: In this paper, the authors used Cinnamomum burmannii extract to improve the quality of food storage, and showed that 10 % sorbitol was able to withstand the rate of fungal growth for 7 days, 15 % sorbol was capable of surviving fungal attack for 5 days, and 20 % sabbathol was resistant to fungal attacks for 3 days.
Abstract: Pectin functions as an adhesive and maintains tissue stability so that it can be used in making edible coating to improve the quality of food storage. One of the producers of pectin is Musa acuminata L. peel (containing 22.4 % pectin). In order not to overgrow with microbes, it is also necessary to have antimicrobial property, which can be obtained from Cinnamomum burmannii extract. This study is about raw material preparation, pectin extraction, pectin modification, Cinnamomum burmannii extraction and edible coating manufacturing. The parameters viz. thickness test, water vapour transmission, tensile strength test, elongation at break, biodegradation, and for trials on storing beef sausage showed that 10 % sorbitol was able to withstand the rate of fungal growth for 7 days; 15 % sorbitol was able to withstand the rate of fungal growth for 5 days; and 20 % sorbitol was able to withstand the rate of fungal growth for 3 days.
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TL;DR: In this paper, the coordination of ligands to the metal ions via nitrogen atoms was analyzed using X-ray powder diffraction and thermal NN. Spectra analysis of the mixed metal complexes showed that metal complexes have a monoclinic system and the preliminary tested in vitro antibacterial activities of Sn(II) complex was assayed against four bacterial isolates.
Abstract: Benzoimidazolphenylethanamine (BPE) has been synthesized using condensation reaction from
o-phenyldiamine and L-phenylalanine. Some metal complexes have been synthesized from
4-(benzoimidazol-2-yl)aniline, benzoimidazolylphenylethanamine and cadmium(II), tin(II), copper(II)
and nickel(II) metal in a molar ratio (1:1:1). All new metal complexes were characterized by
spectroscopic data of FTIR, UV-visible electronic absorption, X-ray powder diffraction and thermal
analysis. Spectra analysis of the mixed metal complexes showed the coordination of ligands to the
metal ions via nitrogen atoms. The XRD powder showed that metal complexes have a monoclinic
system. The preliminary tested in vitro antibacterial activities of Sn(II) complex was assayed against
four bacterial isolates namely Micrococcus luteus, Staphylococcus aureus as Gram-positive,
Pseudomonas aerugmosa and Escherichia coli.
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TL;DR: In this paper, an efficient and facile synthesis of novel fluorinated imidazolium-tagged ionic liquids under microwave irradiation is described, which is shown to have promising activity compared with standard drugs, especially compounds 5 and 6 which consistently produced low IC50 values.
Abstract: An efficient and facile synthesis of novel fluorinated imidazolium-tagged ionic liquids under microwave irradiation is described. Novel prepared ionic liquids was identified and confirmed by spectroscopic and elemental analysis. Synthesized ionic liquids (1-12) was explored for their antiproliferative inhibition potency against three selected human cancer cell lines (MCF-7, HepG-2 and CACO2). Screening results have revealed that some tested ionic liquids exhibited promising activity compared with standard drugs, especially compounds 5 and 6 which consistently produced low IC50 values. Preliminary structure activity relationship (SAR) studies have been performed to identify the relation
between molecular structure and activity. in silico Analysis of ionic liquids was carried out based on ADME, Lipinski rule, drug likeness, toxicity profiles and other physico-chemical properties. All compounds were safe in toxicity profile and computed LD50 values were in accepted range (2.55-2.89 mol/kg). in silico Results have shown that Lipinski rule of five was in accept range, except compound 1 and 2.
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TL;DR: In this paper, the synthesis and characterization of a novel polypyrrole (PPy)/zinc oxide (ZnO)/SWCNT nanocomposite together with pristine Pyrrole is reported.
Abstract: Herein, the synthesis and characterization of a novel polypyrrole (PPy)/zinc oxide (ZnO)/SWCNT
nanocomposite together with pristine polypyrrole is reported. These as-prepared materials have been
characterized by FT-IR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM),
transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) techniques. The PPy/
ZnO/SWCNT nanocomposite is used as a pellet-shaped ammonia sensor. The sensing response is
calculated in terms of variation in the DC electrical conductivity at different concentration of ammonia
ranging from 50 ppm to 2000 ppm. The sensing response of the sensor is determined at 2000, 1000,
500, 400, 300, 200, 100 and 50 ppm and found to be 76.3, 60.5, 54.8, 52.6, 50.2, 48.5, 40.5 and 36.6%,
respectively The sensor displays excellent reversibility along with very high selectivity and stability.
Finally, a sensing mechanism is also proposed involving polarons (charge carriers) of polypyrrole and
lone pairs of electrons of ammonia molecules.
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TL;DR: In this article, the synthesis and characterization of a novel polypyrrole (PPy)/tin oxide (SnO2)/MWCNT nanocomposite along with pristine poly pyrrole is reported.
Abstract: In present study, the synthesis and characterization of a novel polypyrrole (PPy)/tin oxide
(SnO2)/MWCNT nanocomposite along with pristine polypyrrole is reported. These materials have
been studied for their structural and morphological properties by FT-IR spectroscopy, X-ray diffraction
(XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques.
PPy/SnO2/MWCNT nanocomposite has been converted into a pellet-shaped sensor, and its ammonia
sensing studies were carried out by calculating the variation in the DC electrical conductivity at different
concentration of ammonia ranging from 10 to 1500 ppm. The sensing response of the sensor was
determined at 1500, 1000, 500, 200, 100 and 10 ppm and found to be 70.4, 66.1, 62.2, 55.4, 50.8 and
39.7%, respectively The sensor showed a complete reversibility at lower concentrations along with
excellent selectivity and stability. Finally, a sensing mechanism was also proposed involving polarons
(charge carriers) of polypyrrole and lone pairs of ammonia molecules
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TL;DR: In this paper, the quantum chemical calculations of organic compounds viz. (E)-1-(2,6-bis(4-chlorophenyl)-3-methylpiperidine-4-ylidene)-2-phenylhydrazine (3MCl) have been performed by density functional theory using B3LYP method with 6-311G (d,p) basis set.
Abstract: The quantum chemical calculations of organic compounds viz. (E)-1-(2,6-bis(4-chlorophenyl)-3-ethylpiperidine-4-ylidene)-2-phenyl-hydrazine (3ECl), (E)-1-(2,6-bis(4-chlorophenyl)-3-methylpiperidine-4-ylidene)-2-phenylhydrazine (3MCl) and (E)-1-(2,6-bis(4-chloro-phenyl)-3,5-dimethylpiperidine-4-ylidene)-2-phenylhydrazine (3,5-DMCl) have been performed by density functional theory (DFT) using B3LYP method with 6-311G (d,p) basis set. The electronic properties such as Frontier orbital and band gap energies have been calculated using DFT. Global reactivity descriptor has been computed to predict chemical stability and reactivity of the molecule. The chemical
reactivity sites of compounds were predicted by mapping molecular electrostatic potential (MEP) surface over optimized geometries and comparing these with MEP map generated over crystal structures. The charge distribution of molecules predict by using Mulliken atomic charges. The non-linear optical property was predicted and interpreted the dipole moment (μ), polarizability (α) and hyperpolarizability (β) by using density functional theory.