Ascorbic acid or vitamin C is mostly found in natural products such as fruits and vegetables. High performance liquid chromatography (HPLC) method has been developed and validated to compare the ascorbic acid content in Benincasa hispida (Bh) fruit extract with three different extraction solvents; i) 3% metaphosphoric acid, ii) 3% citric acid and iii) distilled water. The compound has been detected and quantified by the use of HPLC coupled with UV-Vis detector. The amount of ascorbic acid detected in Bh fruit extract prepared with different extraction solvents; 3% metaphosphoric acid, 3% citric acid and distilled water were 13.18, 7.91 and 9.42 mg/100g respectively. Total run time was 6 min and the retention time was 2.60 min. Calibration curve was linear with the concentration range 1.00 – 16.00 μg/ml. Limits of detection was 0.24 μg/ml, limit of quantification was 0.81 μg/ml and recovery was 93.52%. The result showed ascorbic acid content is higher in Bh fruit extract with 3% metaphosphoric acid, followed by extract with distilled water and 3% citric acid. Thus, Bh is another novel fruit/ vegetable potentially used as food ingredient as it contains a good source of ascorbic acid that can be good for one’s health.
The extraction method for the determination of ochratoxin A (OTA) in black pepper was optimized. The influence of three variables, i.e., type of solvent, solvent-volume-to-sample- size ratio (v/w) and amount of sodium chloride (NaCl) (g), on OTA recovery was evaluated. Analysis of variance was used to compare recovery values obtained from different solvents, and response surface methodology (RSM) was used to determine the optimum amount of NaCl and the solvent-volume-to-sample-size ratio. The concentration of OTA was determined by high-performance liquid chromatography with fluorescence detection. The highest recovery (95.2 %) was obtained when methanol/water (80:20, v/v) was used as the solvent. The RSM results showed that the experimental data could be adequately fitted to a second-order polynomial model with multiple regression coefficients (R2) of 0.962. The optimum amount of NaCl was determined to be 3 g, whereas the optimum solvent-volume-to-sample-size ratio (v/w) was found to be 4. The proposed method was applied to 20 samples, and the presence of OTA was found in 8 (40%) samples ranging from 0.11 to 3.16 ng g-1.
A gene encoding a thermotolerant lipase with broad pH was isolated from an Antarctic Pseudomonas strain AMS3. The recombinant lipase AMS3 was purified by single-step purification using affinity chromatography, yielding a purification fold of approximately 1.52 and a recovery of 50%. The molecular weight was approximately ∼60 kDa including the strep and affinity tags. Interestingly, the purified Antarctic AMS3 lipase exhibited broad temperature profile from 10-70 °C and stable over a broad pH range from 5.0 to pH 10.0. Various mono and divalent metal ions increased the activity of the AMS3 lipase, but Ni(2+) decreased its activity. The purified lipase exhibited the highest activity in the presence of sunflower oil. In addition, the enzyme activity in 25% v/v solvents at 50 °C particularly to n-hexane, DMSO and methanol could be useful for catalysis reaction in organic solvent and at broad temperature.
Effects of different types of solvent on the antioxidant and antibacterial activity of Quercus infectoria extract have not been well documented. Therefore, extraction process was conducted using conventional Soxhlet extraction with six different types of solvent (100% methanol, ethanol, acetone, water and 70% methanol, and ethanol). High performance liquid chromatography was implemented to identify gallic acid and tannic acid in the extracts. Water extracts contained the highest concentration of both gallic acid and tannic acid compared to other types of solvent; 51.14 mg/g sample and 1332.88 mg/g sample of gallic acid and tannic acid. Meanwhile, antioxidant and antibacterial activity were tested using DPPH free radicals scavenging and disc diffusion assay. Results demonstrated that water extracts gave the highest antioxidant activity (approximately 94.55%), while acetone extract gave the largest inhibition zone for disc diffusion assay (19.00mm respectively). The results also revealed rich sources of gallic acid and tannic acid in Q. infectoria which might provide a novel source of these natural antioxidant and antibacterial activity.
An investigation, on the roots of Piper nigrum and the aerial parts of Piper betle, has yielded several alkaloids. The dried root sample of Piper nigrum was extracted using various solvents in increasing polarity. The dried aerial part of Piper betle was extracted using the Soxhlet extraction method. The alkaloids isolated were pellitorine(1), (E)-1-[3’,4’- (Methylenedioxy)cinnamoyl]piperidine(2), piperine(3), piperolactam D(4), cepharadione A(5), and 2,4-tetradecadienoic acid isobutyl amide(6). These compounds were isolated using chromatographic methods, while the elucidation of the structures was carried out using MS, IR and NMR techniques. The xtracts of Piper nigrum and Piper betle were also tested for cytotoxicity activities. This is the first report on E)-1-[3’,4’-(Methylenedioxy)cinnamoyl] piperidine(2) from Piper nigrum as a natural product.
Cancer still presents enormous challenges in the medical world. Currently, the search for
anticancer compounds has garnered a lot of interest, especially in finding them from the natural
sources. In this study, by using Sulforhodamine B (SRB) colorimetric assay, compounds,
extracted from supermeal worm (Zophobas morio) larvae using two types of acidified organic
solvent (ethanol and isopropanol), were shown to inhibit the growth of a breast cancer line,
MCF-7. A comparative study of the effect was carried out on a normal cell line, Vero. Results
showed that, the two types of extracts inhibits growth of MCF-7 cell at varying degrees, on
the other hand, have much less effect on Vero cell. Extracts analysed by UV-vis spectroscopy,
showed peaks in the range of 260 to 280 nm, inferring the presence of aromatic amino acids,
whereas the highest peak of 3.608 AU at 230 nm indicates the presence of peptide bonds. By
Raman spectroscopy, peaks are observed at 1349 cm-1, 944 cm-1 and 841 cm-1 indicating the
presence of Tyr, Try and Gly, confirming the UV-vis analyses. All results of analyses implied
that the anticancer compounds contain peptides.
This study aimed at investigating the presence of alkaloids and other chemical constituents in Datura stramonium (Saikaran, Jimson weed). All parts of the plant were dried, crushed and then underwent extraction by soxhlet and maceration methods. The solvents used in these methods were normal hexane (nonpolar) and ethanol (polar). Thin Layer Chromatography (TLC) and FTIR techniques were used to analyse the chemical components of jimson weed. The results showed the presence of hyoscine in all plant parts while atropine in the seeds only. The best separation was found to be when the solvent system was acetone: water: ammonia (90:07:03). Maceration method is the best and cost effective procedure for extraction.
The dynamics and conformational landscape of proteins in organic solvents are events of potential interest in nonaqueous process catalysis. Conformational changes, folding transitions, and stability often correspond to structural rearrangements that alter contacts between solvent molecules and amino acid residues. However, in nonaqueous enzymology, organic solvents limit stability and further application of proteins. In the present study, molecular dynamics (MD) of a thermostable Geobacillus zalihae T1 lipase was performed in different chain length polar organic solvents (methanol, ethanol, propanol, butanol, and pentanol) and water mixture systems to a concentration of 50%. On the basis of the MD results, the structural deviations of the backbone atoms elucidated the dynamic effects of water/organic solvent mixtures on the equilibrium state of the protein simulations in decreasing solvent polarity. The results show that the solvent mixture gives rise to deviations in enzyme structure from the native one simulated in water. The drop in the flexibility in H2O, MtOH, EtOH and PrOH simulation mixtures shows that greater motions of residues were influenced in BtOH and PtOH simulation mixtures. Comparing the root mean square fluctuations value with the accessible solvent area (SASA) for every residue showed an almost correspondingly high SASA value of residues to high flexibility and low SASA value to low flexibility. The study further revealed that the organic solvents influenced the formation of more hydrogen bonds in MtOH, EtOH and PrOH and thus, it is assumed that increased intraprotein hydrogen bonding is ultimately correlated to the stability of the protein. However, the solvent accessibility analysis showed that in all solvent systems, hydrophobic residues were exposed and polar residues tended to be buried away from the solvent. Distance variation of the tetrahedral intermediate packing of the active pocket was not conserved in organic solvent systems, which could lead to weaknesses in the catalytic H-bond network and most likely a drop in catalytic activity. The conformational variation of the lid domain caused by the solvent molecules influenced its gradual opening. Formation of additional hydrogen bonds and hydrophobic interactions indicates that the contribution of the cooperative network of interactions could retain the stability of the protein in some solvent systems. Time-correlated atomic motions were used to characterize the correlations between the motions of the atoms from atomic coordinates. The resulting cross-correlation map revealed that the organic solvent mixtures performed functional, concerted, correlated motions in regions of residues of the lid domain to other residues. These observations suggest that varying lengths of polar organic solvents play a significant role in introducing dynamic conformational diversity in proteins in a decreasing order of polarity.
Oil palm (Elaeis guineensis Jacq.) fronds (OPF) are the most abundant oil palm solid wastes that are generated during oil palm agriculture and harvest. Palm oil and some other palm wastes have been reported to contain high concentrations of carotenoids with vital bioactive properties. However, the extraction and quantification of carotenoids from OPF have not been reported. In this study, ultrasonic-assisted extraction, HPLC-FLD for quantification, and response surface methodology (RSM) for optimization of β-carotene, lutein, and zeaxanthin from OPF extracts were investigated. The effects of extraction temperature (X1: 30-70°C), extraction time (X2: 10-50 min), and solvent-sample ratio (X3: 10-50 mL/g) on the recovery of β-carotene (Y1), lutein (Y2), and zeaxanthin (Y3) were investigated using three-level Box-Behnken design (BBD) experiment. At a desirability of 1, the optimum extraction conditions for β-carotene (30.14°C, 37.11 min, and 23.18 mL/g), lutein (30.00°C, 39.09 min, and 19.24 mL/g), and zeaxanthin (30.09°C, 36.76 min, and 22.38 mL/g) yielded carotenoid concentrations of 17.95 μg/g dry weight (DW), 261.99 μg/g DW, and 29.99 μg/g DW, respectively.
Zinc-air flow batteries exhibit high energy density and offer several appealing advantages. However, their low efficiency of zinc utilization resulted from passivation and corrosion of the zinc anodes has limited their broad application. In this work, ethanol, which is considered as an environmentally friendly solvent, is examined as an electrolyte additive to potassium hydroxide (KOH) aqueous electrolyte to improve electrochemical performance of the batteries. Besides, the effects of adding different percentages of ethanol (0-50% v/v) to 8 M KOH aqueous electrolyte were investigated and discussed. Cyclic voltammograms revealed that the presence of 5-10% v/v ethanol is attributed to the enhancement of zinc dissolution and the hindrance of zinc anode passivation. Also, potentiodynamic polarization and electrochemical impedance spectroscopy confirmed that adding 5-10% v/v ethanol could effectively suppress the formation of passivating layers on the active surface of the zinc anodes. Though the addition of ethanol increased solution resistance and hence slightly decreased the discharge potential of the batteries, a significant enhancement of discharge capacity and energy density could be sought. Also, galvanostatic discharge results indicated that the battery using 10% v/v ethanol electrolyte exhibited the highest electrochemical performance with 30% increase in discharge capacity and 16% increase in specific energy over that of KOH electrolyte without ethanol.
This study investigated the recovery of phytochemical antioxidants in Dacryodes rostrata fruit using different extraction solvents. The effects of solvent of varying polarities with sequential extraction method on the recovery of phenolics, flavonoids, carotenoids and anthocyanins from different parts of the fruit (seed, pulp and peel) were determined. Their antioxidant activities were further determined using DPPH radical, ferric reducing antioxidant power (FRAP), hydroxyl radical scavenging, superoxide anion radical scavenging and phosphomolybdenum method. Dacryodes Rostrata seed had the highest total phenolic content with 50% ethanol as the most efficient extraction solvent. The highest total flavonoid content was obtained in ethyl acetate extract of fruit pulp, whereas peel extracted with hexane and 50% ethanol was the highest in total carotenoid content and total anthocyanin content, respectively. The seed extracted with 50% ethanol exhibited the strongest DPPH radical scavenging activity. Iron chelating activity measured by FRAP assay was the best in seed extracts, particularly in those polar extracts derived from water and 50% ethanol. Antioxidant activities of 50% ethanol extract of D. rostrata seed was the highest when determined by FRAP and phosphomolydenum assays. However, the influence of extraction solvents is not distinctly shown by hydroxyl radical and superoxide anion radical scavenging activities. This is the first report on the effect of various extraction solvents on the recovery of phytochemicals in D. rostrata fruit parts and the seed of D. rostrata is a potential source of polar antioxidants.
A portable microchip electrophoresis (MCE) coupled with on-chip contactless conductivity detection (C(4)D) system was evaluated for the determination of vancomycin in human plasma. In order to enhance the detection sensitivity, a new online multi-stacking preconcentration technique based on field-enhanced sample injection (FESI) and micelle-to-solvent stacking (MSS) was developed and implemented in MCE-C(4)D system equipped with a commercially available double T-junction glass chip. The cationic analytes from the two sample reservoirs were injected under FESI conditions and subsequently focused by MSS within the sample-loading channel. The proposed multi-stacking strategy was verified under a fluorescence microscope using Rhodamine 6G as the model analyte and a sensitivity enhancement factor (SEF) of up to 217 was achieved. The developed approach was subsequently implemented in the aqueous-based MCE, coupled to C(4)D in order to monitor the targeted antibiotic (in this case, vancomycin) present in human plasma samples. The multi-stacking and analysis time for vancomycin were 50s and 250s respectively, with SEF of approximately 83 when compared to typical gated injection. The detection limit of the method for vancomycin was 1.2μg/mL, with intraday and interday repeatability RSDs of 2.6% and 4.3%, respectively. Recoveries in spiked human plasma were 99.0%-99.2%.
The development of nano-sized scaffolds with antibacterial properties that mimic the architecture of tissue is one of the challenges in tissue engineering. In this study, polycaprolactone (PCL) and PCL/gelatine (Ge) (70:30) nanofibrous scaffolds were fabricated using a less toxic and common solvent, formic acid and an electrospinning technique. Nanofibrous scaffolds were coated with silver (Ag) in different concentrations of silver nitrate (AgNO3) aqueous solution (1.25, 2.5, 5, and 10 %) by using dipping method, drying and followed by ultraviolet (UV) photoreduction. The PCL/Ge (70:30) nanofibrous scaffold had an average fibre diameter of 155.60 ± 41.13 nm. Characterization showed that Ag was physically entrapped in both the PCL and PCL/Ge (70:30) nanofibrous scaffolds. Ag(+) ions release study was performed and showed much lesser release amount than the maximum toxic concentration of Ag(+) ions in human cells. Both scaffolds were non-toxic to cells and demonstrated antibacterial effects towards Gram-positive Bacillus cereus (B. cereus) and Gram-negative Escherichia coli (E. coli). The Ag/PCL/Ge (70:30) nanofibrous scaffold has potential for tissue engineering as it can protect wounds from bacterial infection and promote tissue regeneration.
The low conductivity of separation electrolytes employed in nonaqueous capillary electrophoresis (NACE) limits the use of on-line sample concentration or stacking by field enhancement. Herein, micelle-to-solvent stacking (MSS) was performed by the simple injection of a micellar solution plug prior to electrokinetic injection of sample prepared under field-enhanced stacking conditions (known as field-enhanced sample injection, FESI). The proposed approach allowed a 214-625-fold improvement in peak signals for targeted anticancer drugs (e.g., tamoxifen) and its major metabolites in NACE using 100% methanol-based separation electrolyte that comprised of 7.5mM deoxycholic acid sodium salt, 15mM acetic acid and 1mM 18-crown-6. These improvements yielded tamoxifen and its metabolites with 2-5 times better stacking efficiency as compared to those obtained without micellar solution injection or FESI only. This is comparable to the results typically achieved when FESI is combined with isotachophoresis (electrokinetic supercharging). The FESI-MSS-NACE was tested for the measuring levels of target drugs in plasma. The analytical figures of merit are also reported.
The stabilization mechanism of natural rubber (NR) latex from Hevea brasiliensis was studied to investigate the components involved in base-catalyzed ester hydrolysis, namely, hydrolyzable lipids, ammonia, and the products responsible for the desired phenomenon observed in ammonia-preserved NR latex. Latex stability is generally thought to come from a rubber particle (RP) dispersion in the serum, which is encouraged by negatively charged species distributed on the RP surface. The mechanical stability time (MST) and zeta potential were measured to monitor field latices preserved in high (FNR-HA) and low ammonia (FNR-LA) contents as well as that with the ester-containing components removed (saponified NR) at different storage times. Amounts of carboxylates of free fatty acids (FFAs), which were released by the transformation and also hypothesized to be responsible for the like-charge repulsion of RPs, were measured as the higher fatty acid (HFA) number and corroborated by confocal laser scanning microscopy (CLSM) both qualitatively and quantitatively. The lipids and their FFA products interact differently with Nile red, which is a lipid-selective and polarity-sensitive fluorophore, and consequently re-emit characteristically. The results were confirmed by conventional ester content determination utilizing different solvent extraction systems to reveal that the lipids hydrolyzed to provide negatively charged fatty acid species were mainly the polar lipids (glycolipids and phospholipids) at the RP membrane but not those directly linked to the rubber molecule and, to a certain extent, those suspended in the serum. From new findings disclosed herein together with those already reported, a new model for the Hevea rubber particle in the latex form is proposed.
This study describes a dispersive liquid-liquid microextraction combined with dispersive solid-phase extraction method based on phenyl-functionalized magnetic sorbent for the preconcentration of polycyclic aromatic hydrocarbons from environmental water, sugarcane juice, and tea samples prior to gas chromatography with mass spectrometry analysis. Several important parameters affecting the extraction efficiency were investigated thoroughly, including the mass of sorbent, type and volume of extraction solvent, extraction time, type of desorption solvent, desorption time, type and amount of salt-induced demulsifier, and sample volume. Under the optimized extraction and gas chromatography-mass spectrometric conditions, the method revealed good linearity (10-100000 ng/L) with coefficient of determination (R2 ) of ≥0.9951, low limits of detection (3-16 ng/L), high enrichment factors (61-239), and satisfactory analyte recoveries (86.3-109.1%) with the relative standard deviations
The influence of methanol as a solvent on the properties of sodium alginate/sulfonated graphene oxide (SA/SGO) membranes was explored in water-methanol mixed conditions with various methanol concentrations and temperatures through molecular dynamics simulations. The methanol uptake of the membrane showed an isolation phase determined from the simulation results. The distance between the sulfonic acid groups increased in higher methanol concentrations, as observed from S-S RDFs. Furthermore, the distance between the SA-chain RDFs and the solvent molecules was analysed to determine a) the affinity of water towards the sulfonic acid groups and b) the affinity of the aromatic backbone of the SA towards methanol molecules. A decrease in water molecule diffusion led to an increase in methanol diffusion and uptake. SA/SGO membranes exhibited a smaller diffusion coefficient than that for the Nafion membranes, as calculated from simulation results and compared to the experimental work. Additionally, the diffusion ability increased at higher temperatures for all permeants. The interaction information obtained is useful for DMFC applications.
Recently natural polyphenol compounds (PCs) of plants, gained wide consideration of
scientists, companies and public people because of its unique pharmaceutical and
preservative benefits in the physiological system. They can prevent mortal and serious
diseases such as cancer, cardiovascular and Alzheimer. However, defining a suitable
source of PCs and their proper, economic and efficient extraction method are still a
challenge. The aim of this study was to review PCs as an important antioxidant, the
significance of pomegranate as a source of natural PCs and its application in meat and
meat product. This study also covers different types of PCs extraction methods such as
solid-liquid extraction (SLE) method as a conventional extraction which using Soxhlet
apparatus and several solvents and advanced methods such as microwave-assisted
extraction (MAE), supercritical fluid extraction (SFE), accelerated solvent extraction
(ASE), ultrasound-assisted extraction (UAE) and high hydrostatic pressure extraction
(HHPE). Simple and developed analytical method of PCs is also reviewed in the study.
SLE method is an easy and simple method but, it uses lots of chemicals and is not
suitable for all kinds of PCs extraction. UAE is using for quick extraction PCs, SFE is green
extraction method uses less solvent and have a good result but it needs high
technology. ASE method is a proper alternative for Soxhlet extraction method for its
quick result. MAE method has high extraction result but is not suitable for some
thermolabile PCs. Several parts of pomegranate showed antioxidant and antimicrobial
traits for shelf life extension of meat and meat product. Pomegranate peel is the
strongest antioxidant followed by pomegranate juice and seed. Pomegranate peel
prolonged chilled chicken meat shelf live up to three weeks.
The recognition of nanocellulose has been prominent in recent years as prospect materials, yet the ineffectiveness of nanocellulose to disperse in an organic solvent has restricted its utilization, especially as a reinforcement in polymer nanocomposite. In this study, cellulose has been isolated and defibrillated as cellulose nanofibrils (CNF) from oil palm empty fruit bunch (EFB) fibers. Subsequently, to enhance its compatibility with UV-curable polyurethane (PU)-based resin, the surface hydrophilicity of CNF has been tailored with polyethylene glycol (PEG), as well as reduced graphene oxide (rGO). The dispersibility of reinforced modified CNF in UV-curable PU was examined through the transmittance interruption of resin, chemical, and mechanical properties of the composite printed using the stereolithographic technique. Evidently, the enhanced compatibility of modified CNF and UV-curable PU was shown to improve the tensile strength and hardness of the composites by 37% and 129%, respectively.
Lutein available in the current market is derived from marigold petals. However, extensive studies showed that microalgae are rich in lutein content and potentially exploitable for its dietary and other industrial applications. In this study, microwave assisted binary phase solvent extraction method (MABS) was the novel protocol being developed and optimized to achieve maximum lutein recovery from microalgae Scenedesmus sp. biomass. Results showed that 60% potassium hydroxide solution with acetone in the ratio of 0.1 (ml/ml) was the ideal binary phase solvent composition. Empirical model developed using response surface methodology revealed highest lutein content can be recovered through MABS extraction method at 55 °C treatment temperature, 36 min in extraction time, 0.7 (mg/ml) for biomass to solvent ratio, 250 Watt microwave power and 250 rpm stirring speed. This optimized novel protocol had increased the amount of lutein recovered by 130% and shorten the overall extraction time by 3-folds.