One of the major trends within the food industry is the replacement of synthetically-derived food additives (e.g. emulsifiers) by natural alternatives. A promising approach is the utilization of saponins that have attracted attention due to their effective emulsifying properties and their natural origin from plants. Panax ginseng is well known in Asian countries for its health benefits that are mainly attributed to amphiphilic triterpene saponins, namely ginsenosides. In this study, we characterized two food-grade ginseng extracts (Finzelberg: FB; CheilJedang: CJ) regarding their chemical composition, surface activity, and effectiveness as emulsifier. Both ginseng extracts reduced the interfacial tension appreciably by up to 80%, and formed negatively charged oil-in-water emulsions at a low emulsifier-to-oil ratio. Ginseng FB formed small submicron-sized emulsions, whereas the mean particle sizes with ginseng CJ were much larger (up to 25 μm). Both ginseng extract-stabilized emulsions were stable towards a range of stresses (pH 4–9, ≤100 mM NaCl) or when stored at ≤25 °C for four weeks. However, the emulsions showed instability at highly acidic conditions (pH 2–3), during the 4-week storage at an elevated temperature (55 °C), and at high ionic strengths (≥250 mM NaCl, >10 mM CaCl2), which was mainly attributed to the reduction or screening of electrostatic repulsion. Emulsion formation and stabilization was proposed to occur via formation of a saponin or biogenic saponin-protein complex layer leading to a stronger interfacial network. In conclusion, both ginseng extracts were able to form emulsions, although ginseng FB extract showed especially remarkable emulsifying properties, similar to the highly effective Quillaja saponaria extract. The results may therefore be helpful in replacing other emulsifiers and formulating emulsion products with varying particle size ranges.
The influence of lipid concentration on the ability of excipient emulsions to increase carotenoid bioaccessibility from raw and cooked carrots was investigated using a simulated gastrointestinal tract (GIT). Excipient emulsions were fabricated using whey protein as a natural emulsifier and a long chain triglyceride (corn oil) as a digestible lipid. Changes in particle size, charge, and microstructure were determined as the carrot-emulsion mixtures were passed through simulated mouth, stomach, and small intestine. Carotenoid bioaccessibility increased with increasing digestible lipid concentration in the excipient emulsions (from 0 to 8 %). Carotenoid bioaccessibility was higher from boiled carrots than for raw carrots, which was attributed to disruption of plant cell structure facilitating carotenoid release. In conclusion, excipient emulsions are highly effective at increasing carotenoid bioaccessibility from carrots, which can be attributed to the ability of the small lipid droplets to rapidly solubilize the carotenoids. 相似文献
In recent years, growers have used various production types, including high-tunnel systems, to increase the yield of tomatoes (Lycopersicon esculentum). However, the effect of high-tunnel cultivation, in comparison to conventional open-field production, on aroma and flavor volatiles is not fully understood.
Objectives
To optimize the extraction and quantification conditions for the analysis of tomato volatiles using headspace solid phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS), and study the effect of production systems on volatile profiles using metabolomics approach.
Methods
The HS-SPME conditions were optimized for extraction and GC–MS was used to quantify the volatiles from four tomato varieties grown in open-field and high-tunnel systems. Univariate and multivariate analyses were performed to identify the influence of production system on tomato volatiles.
Results and conclusions
The extraction of 2 g tomato samples at 60 °C for 45 min using divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber gave the maximum amounts of volatiles. This optimized method was used to identify and quantify 41 volatiles from four tomato varieties. The levels of β-damascenone were higher in the high-tunnel tomatoes and geranylacetone was higher in open-field tomatoes. These two volatile compounds could be considered as biomarkers for tomatoes grown in high-tunnel and open-field production systems. This study is the first report comparing volatiles in tomatoes grown in high-tunnel and open-field conditions, and our results confirmed that there is a critical need to adopt biomarker-specific production systems to improve the nutritional and organoleptic properties of tomatoes.
Development of new energetic salts is the key factor in replacing low performance compounds in conventional formulations of high explosives as well as propellants. Ten salts based on the nitroformate anion and various nitrogen-rich cations were designed and their geometric optimizations carried out using the density functional method. With reasonable oxygen balance (from ?36 % to 0 %), heats of formation (47–624 kJ mol?1) and high densities (1.81–1.89 g cm?3), the detonation velocity (D) and pressure (P) values of salts were calculated as 8.62–9.36 km s?1 and 33.10–40.01 GPa, respectively. Lastly, the nitroformate salts studied in this work are of prospective interest as high performance explosives.
We aimed to identify new high-yield dextranase strains and study the catalytic potential of dextranase from the strain in industrial applications.
Results
Dextranase-producing strains were screened from soil samples, and a potential strain was identified as Chaetomium globosum according to its phenotype, biochemical characteristics, and rDNA analysis. Crude dextranase was purified to reach 10.97-fold specific activity and 18.7% recovery. The molecular weight of the enzyme was 53 kDa with an optimum temperature and pH of 60 °C and 5.5, respectively. Enzyme activity was stable at pH 4.0–7.0 and displayed sufficient thermal stability at temperatures?<?50 °C. Mn2+ (10 mM) enhanced dextranase activity by 134.44%. The enzyme was identified as an endodextranase. It displayed very high hydrolytic affinity toward high-molecular weight dextran T2000, reaching 97.9% hydrolysis within 15 min at 2 U/mL.
Conclusion
Collectively, these results suggest that Chaetomium globosum shows higher production and specificity of dextranase than that from other reported strains. These findings may offer new insights into the potential of dextranase in the sugar, medical, and food industries.
Beryllium telluride (BeTe) with cubic zinc-blende (ZB) structure was studied using ab initio constant pressure method under high pressure. The ab initio molecular dynamics (MD) approach for constant pressure was studied and it was found that the first order phase transition occurs from the ZB structure to the nickel arsenide (NiAs) structure. It has been shown that the MD simulation predicts the transition pressure PT more than the value obtained by the static enthalpy and experimental data. The structural pathway reveals MD simulation such as cubic → tetragonal → orthorhombic → monoclinic → orthorhombic → hexagonal, leading the ZB to NiAs phase. The phase transformation is accompanied by a 10% volume drop and at 80 GPa is likely to be around 35 GPa in the experiment. In the present study, our obtained values can be compared with the experimental and theoretical results.
To improve the efficiency of reactions of β-glucuronidase (GUS)-assisted glucuronic acid (GluA) removal within a microfluidic system.
Results
β-glucuronidase from Helix pomatia was immobilised and characterised in silica-based sol–gel monoliths. Efficiency of the GUS-doped silica monoliths was tested for hydrolysis of p-Nitrophenyl-β-d-glucuronide (pNP–GluA) in both ml-scaled medium via batch reactions and microfluidic environment via continuous-flow reactions. In the microfluidic platform, within a duration of 150 min of continuous operation (flow rate: 1 µL/min), the obtained highest pNP yield was almost 50% higher than that of the corresponding batchwise reaction. However, increased flow rates (3, 5, and 10 µL/min) resulted in lower conversion yields compared to 1 µL/min. The microfluidic platform demonstrated continuous hydrolytic activity for 7 days with considerable reaction yields while using a small amount of the enzyme.
Conclusion
These results revealed that usage of the microreactors has considerable potential to efficiently obtain bioactive GluA-free aglycons from various plant-derived β-glucuronides for pharmaceutical applications.
In today’s consumer perception of industrial processes and food production, aspects like food quality, human health, environmental safety, and energy security have become the keywords. Therefore, much effort has been extended toward adding value to biowastes of agri-food industries through biorefinery processing approaches. This study focused, for the first time, on the valorization of tomato by-products of a Tunisian industry for the recovery of value-added compounds using biorefinery cascade processing.
Results
The process integrated supercritical CO2 extraction of carotenoids within the oil fractions from tomato seeds (TS) and tomato peels (TP), followed by a batch isolation of protein from the residues. The remaining lignocellulosic matter from both fractions was then submitted to a liquid hot water (LHW) hydrolysis. Supercritical CO2 experiments extracted 5.79% oleoresin, 410.53 mg lycopene/kg, and 31.38 mg β-carotene/kg from TP and 26.29% oil, 27.84 mg lycopene/kg, and 5.25 mg β-carotene/kg from TS, on dry weights. Protein extraction yields, nearing 30% of the initial protein contents equal to 13.28% in TP and 39.26% in TS, revealed that TP and TS are a rich source of essential amino acids. LHW treatment run at 120–200 °C, 50 bar for 30 min showed that a temperature of 160 °C was the most convenient for cellulose and hemicellulose hydrolysis from TP and TS, while keeping the degradation products low.
Conclusions
Results indicated that tomato by-products are not only a green source of lycopene-rich oleoresin and tomato seed oil (TSO) and of protein with good nutritional quality but also a source of lignocellulosic matter with potential for bioethanol production. This study would provide an important reference for the concept and the feasibility of the cascade fractionation of valuable compounds from tomato industrial by-products.
Herein we describe a UPLC-FLD-based method for the quantification of the sialic acid content of red meat, using a synthetic neuraminic acid derivative as an internal standard. X-Gal-α-2,6-N-propionylneuraminic acid was synthesized via a chemoenzymatic pathway and its hydrolytic stability was characterized. Known quantities of this compound were incubated with samples of red meat under sialic acid-releasing conditions. The released sialic acids were derivatized, analyzed by UPLC-FLD, and the Neu5Ac/Neu5Gc content of the meat sample was determined by comparison with the internal standard. A number of red meats were analyzed by this method with the following results (Neu5Ac μg/g tissue, Neu5Gc μg/g tissue ± s.d.): pork (68 ± 3, 15.2 ± 0.7), beef (69 ± 8, 36 ± 5), lamb (46 ± 2, 33 ± 1), rabbit (59 ± 2, 0.4 ± 0.4), and hare (50 ± 4, 1 ± 1). We envisage that this methodology will find application in investigating the health effects of dietary Neu5Gc.
In this article, we explore, both theoretically and experimentally, the general reactivity of alkyl hydrogeno-phenylphosphinates with alcohols. We show that alcohol molecules act exclusively as nucleophilic species, and add to alkyl hydrogeno-phenylphosphinates, leading to pentacoordinated intermediates. These intermediates are shown to subsequently competitively undergo alcohol eliminations and/or Berry pseudorotations. This offers several possible routes for racemizations and/or alcohol exchange reactions. Transition standard Gibbs free energies predicted from DFT calculations for the overall alcohol exchange mechanism are shown to be compatible with those experimentally measured in case ethanol reacts with ethyl hydrogeno-phenylphosphinate (134.5～136.0 kJ mol?1 at 78 °C).
A post-calculation correction is established for PM7 band gaps of transition-metal oxides. The correction is based on the charge on the metal cation of interest, as obtained from MOPAC PM7 calculations. Application of the correction reduces the average error in the PM7 band gap from ~3 eV to ~1 eV. The residual error after correction is shown to be uncorrelated to the Hartree–Fock method upon which PM7 is based.
Graphical Abstract Comparison between calculated band gaps and experimental band gaps for binary oxides. The orange crosses are for corrected PM7 band gaps. Blue squares are uncorrected values. The orange crosses fall closer to the diagonal dashed line, showing an overall improvement of the accuracy of calculated values
As a major lignocellulosic biomass, which represented more than half of the world’s agricultural phytomass, crop residues have been considered as feedstock for biofuel production. However, large-scale application of this conventional biofuel process has been facing obstacles from cost efficiency, pretreatment procedure, and secondary pollution. To meet the growing demands for food, feed, and energy as the global population continues to grow, certain kinds of insects, many of which are voracious feeders of organic wastes that may help address environmental, economic, and health issues, have been highlighted as a source of protein and fat.
Results
The biorefinery studied includes initial corn stover degradation by yellow mealworm (Tenebrio molitor L.), followed by a second stage that employs black soldier fly (Hermetia illucens L.), to utilize the residues produced during the first stage. These two insect-based biorefinery yielded 8.50 g of insect biomass with a waste dry mass reduction rate of 51.32%, which resulted in 1.95 g crude grease from larval biomass that produced 1.76 g biodiesel, 6.55 g protein, and 111.59 g biofertilizer. The conversion rate of free fatty acids of crude grease into biodiesel reached 90%. The components of cellulose, hemicellulose, and lignin contained in corn stover hydrolyzed harmoniously, resulting in declines of 45.69, 51.85, and 58.35%, respectively. Moreover, fluctuations in lipid, protein, and reducing sugar were also analyzed.
Conclusion
The investigation findings demonstrated that successive co-conversion of corn stover by insects possessing different feeding habits could be an attractive option for efficient utilization of lignocellulosic resources, and represents a potentially valuable solution to crop residues management, rise of global liquid energy, and animal feed demand.
Recently, a series of xanthone analogues has been identified as α-glucosidase inhibitors. To provide deeper insight into the three-dimensional (3D) structural requirements for the activities of these molecules, CoMFA and CoMSIA approaches were employed on 54 xanthones to construct 3D-QSAR models. Their bioactive conformations were first investigated by docking studies and optimized by subsequent molecular dynamics (MD) simulations using the homology modeled structure of the target protein. Based on the docking/MD-determined conformers, 3D-QSAR studies generated several significant models in terms of 47 molecules as the training set. The best model (CoMSIA-SHA) yielded q2 of 0.713, r2 of 0.967 and F of 140.250. The robustness of the model was further externally confirmed by a test set of the remaining molecules (q2 = 0.793, r2 = 0.902, and k = 0.905). Contour maps provided much information for future design and optimization of new compounds with high inhibitory activities towards α-glucosidase.
Plant-based foods contain numerous bioactive constituents (“nutraceuticals”) that have beneficial effects on human health. However, their oral bioavailability is often relatively low, which limits their potential efficacy. The bioavailability of nutraceuticals can be increased through the utilization of excipient foods whose compositions and structures are specifically designed to increase the amount of nutraceuticals absorbed in an active form. In this study, olive oil excipient emulsions were designed to increase the bioaccessibility of lycopene and other natural antioxidants in tomato pomace. These emulsions consisted of 8 wt% olive oil and 1 wt% Tween 20 or Tween 80 and were prepared using a microfluidizer operated under different processing conditions (12,000 or 20,000 psi; 3 or 5 passes). Changes in particle size, charge, and bioaccessibility were assessed when tomato pomace-emulsion mixtures were exposed to simulated gastrointestinal digestion. The mean particle diameter of the particles in the excipient emulsions increased after digestion (416 to 446 nm) compared to the values before digestion (200 to 220 nm). The presence of excipient emulsions significantly increased the bioaccessibility of lycopene in tomato pomace compared to oil-free control samples. For instance, lycopene bioaccessibility was > 82% when the tomato pomace was mixed with excipient emulsions but only 29% when it was mixed with oil-free buffer solutions. The presence of excipient emulsions also increased the total phenolic content of the tomato pomace. For instance, the phenolic content was considerably higher in the presence of excipient emulsions (1489 to 2055 mg GAE /100 g FW) than in their absence (939 mg GAE /100 g FW). However, the excipient emulsions did not increase naringenin bioaccessibility, which was attributed to the fact that it was not strongly hydrophobic. The efficacy of the excipient emulsions was only modestly dependent on emulsifier type and homogenization conditions. In conclusion, excipient emulsions can be designed to enhance the bioaccessibility of strongly hydrophobic nutraceuticals in tomato-based products, which may boost their healthiness.
A new compound based on the D-π-A concept, where D = dimethylamino-phenyl and A = naphthoic acid, separated by an imine motif, was designed, synthesized and characterized. The spectral, energetics, and structural characteristics of the compound were studied thoroughly theoretically by density functional theory (DFT) in the gas and aqueous phases and experimentally (steady-state absorption) in aqueous media with various degrees of polarity and hydrogen bonding ability. This compound shows high sensitivity to the polarity, basicity and proton affinity of the environment. Based on DFT, TD-DFT and NBO analysis, the compound exists in the ground-state with both intermolecular and intramolecular hydrogen bond conformations in association with the –COOH, with latter isomer calculated to be more stable. Furthermore, structural changes via intermolecular solute–solvent interactions, dictate electronic modifications and spectral changes.
Molecular dynamics simulations were performed to investigate the separation of trihalomethanes (THMs) from water using boron nitride nanosheets (BNNSs). The studied systems included THM molecules and a functionalized BNNS membrane immersed in an aqueous solution. An external pressure was applied to the z axis of the systems. Two functionalized BNNSs with large fluorinated-hydrogenated pore (F-H-pores) and small hydrogen-hydroxyl pore (H-OH-pores) were used. The pores of the BNNS membrane were obtained by passivating each nitrogen and boron atoms at the pore edges with fluorine and hydrogen atoms in the large pore or with hydroxyl and hydrogen atoms in the small pore. The results show that the BNNS with a small functionalized pore was impermeable to THM molecules, in contrast to the BNNS with a large functionalized pore. Using these membranes, water contaminants can be removed at lower cost.
Graphical Abstract A snapshot of the simulation system. The BNNS membrane with the large functionalized pore is located in the middle of the box. The size of the box is 3 × 3 × 5 nm3. Green chlorine, cyan carbon, red oxygen, white hydrogen
The characterization of the seleno-sulfide-bromo systems and the isomerization process on the [H, S, Se, Br] potential energy surface were investigated using state-of-the-art theoretical methods. The CCSD(T) and the MP2 levels of theory were employed along with the series of correlation consistent basis sets extrapolated to the complete basis set (CBS) limit in the optimization of the geometrical parameters and computation of electronic energies. The relative stability, in kcal mol?1, at the CCSD(T)/CBS follows the trend: HSSeBr (0) > HSeSBr (9.51) > SSeHBr (24.02) > SeSHBr (25.42). This order was observed in the previous study of the [H, S, Se, Cl] species. The structural parameters and vibrational frequencies of the [H, S, Se, Br] species are reported. This research work should be helpful to experimentalists in order to gain insights into these novel heteroatom molecules.
Graphical abstract Relative energy profile (in kcal mol?1) using the CCSD(T)/CBS and MP2/CBS (in parentheses) method of the stationary states on the [H, S, Se, Br] PES.
Spin-polarized first-principles total-energy calculations have been performed to investigate the possible chain reaction of acetylene molecules mediated by hydrogen abstraction on hydrogenated hexagonal boron nitride monolayers. Calculations have been done within the periodic density functional theory (DFT), employing the PBE exchange correlation potential, with van der Waals corrections (vdW-DF). Reactions at two different sites have been considered: hydrogen vacancies on top of boron and on top of nitrogen atoms. As previously calculated, at the intermediate state of the reaction, when the acetylene molecule is attached to the surface, the adsorption energy is of the order of ?0.82 eV and ?0.20 eV (measured with respect to the energy of the non interacting molecule-substrate system) for adsorption on top of boron and nitrogen atoms, respectively. After the hydrogen abstraction takes place, the system gains additional energy, resulting in adsorption energies of ?1.52 eV and ?1.30 eV, respectively. These results suggest that the chain reaction is energetically favorable. The calculated minimum energy path (MEP) for hydrogen abstraction shows very small energy barriers of the order of 5 meV and 22 meV for the reaction on top of boron and nitrogen atoms, respectively. Finally, the density of states (DOS) evolution study helps to understand the chain reaction mechanism.
Vascular dementia (VaD) is a degenerative cerebrovascular disorder that leads to progressive decline in cognitive abilities and memory. Several reports demonstrated that oxidative stress and endothelial dysfunction are principal pathogenic factors in VaD. The present study was constructed to determine the possible neuroprotective effects of simvastatin in comparison with cilostazol in VaD induced by l-methionine in rats. Male Wistar rats were divided into four groups. Group I (control group), group II received l-methionine (1.7 g/kg, p.o.) for 32 days. The remaining two groups received simvastatin (50 mg/kg, p.o.) and cilostazol (100 mg/kg, p.o.), respectively, for 32 days after induction of VaD by l-methionine. Subsequently, rats were tested for cognitive performance using Morris water maze test then sacrificed for biochemical and histopathological assays. l-methionine induced VaD reflected by alterations in rats’ behavior as well as the estimated neurotransmitters, acetylcholinesterase activity as well as increased brain oxidative stress and inflammation parallel to histopathological changes in brain tissue. Treatment of rats with simvastatin ameliorated l-methionine-induced behavioral, neurochemical, and histological changes in a manner comparable to cilostazol. Simvastatin may be regarded as a potential therapeutic strategy for the treatment of VaD. To the best of our knowledge, this is the first study to reveal the neuroprotective effects of simvastatin or cilostazol in l-methionine-induced VaD.
Excessive consumption of fluoride (F) through drinking, eating, and/or environmental contaminants induces chronic toxicity known as fluorosis. Our previous research has shown that fluorosis was associated with male reproductive disorders. The current study is designed to explain the protective effect of vitamin E (VE), insulin-like growth factor-I (IGF-I), and human chorionic gonadotropin (hCG) against natrium fluoride (NaF)-induced alterations in isolated Leydig cells (LCs). These NaF-induced alterations include decreased cell proliferation, steroidogenesis, and relative gene expression. Isolated LCs were incubated with NaF (0, 5, 20 mg/L) and/or 10 μg/ml VE, 100 ng/ml IGF-I, and 100 IU/ml hCG. NaF-treated cells’ ability to secrete testosterone (T) was significantly less than other treated groups (P < 0.05). Additionally, in NaF-treated cells, there was a significant upregulation of certain relative mRNA expressions such as Star and Cyp11a, as well as significantly less cell proliferation in a dose-dependent manner (P < 0.05). These data clearly show that VE, IGF-1, and hCG have a protective effect in the LCs functions. Taken together, the final results of this study shown herein are consistent with the assumption that VE, IGF-I, and hCG volunteered ameliorative effects against the deleterious effects of NaF through their protective activity. Although it is hypothesized that ameliorative effects might have been involved, the fundamental pathway(s) remain(s) to be illuminated.
