Binder-Free LiMn2 O4 Nanosheets on Carbon Cloth for Selective Lithium Extraction from Brine via Capacitive Deionization.

In this study, a three-step strategy including electrochemical cathode deposition, self-oxidation, and hydrothermal reaction is applied to prepare the LiMn2 O4 nanosheets on carbon cloth (LMOns@CC) as a binder-free cathode in a hybrid capacitive deionization (CDI) cell for selectively extracting lithium from salt-lake brine. The binder-free LMOns@CC electrodes are constructed from dozens of 2D LiMn2 O4 nanosheets on carbon cloth substrates, resulting in a uniform 2D array of highly ordered nanosheets with hierarchical nanostructure. The charge/discharge process of the LMOns@CC electrode demonstrates that visible redox peaks and high pseudocapacitive contribution rates endow the LMOns@CC cathode with a maximum Li+ ion electrosorption capacity of 4.71 mmol g-1 at 1.2 V. Moreover, the LMOns@CC electrode performs outstanding cycling stability with a high-capacity retention rate of 97.4% and a manganese mass dissolution rate of 0.35% over ten absorption-desorption cycles. The density functional theory (DFT) theoretical calculations verify that the Li+ selectivity of the LMOns@CC electrode is attributed to the greater adsorption energy of Li+ ions than other ions. Finally, the selective extraction performance of Li+ ions in natural Tibet salt lake brine reveals that the LMOns@CC has selectivity ( α Mg 2 + Li + $\alpha _{{\mathrm{Mg}}^{2 + }}^{{\mathrm{Li}}^ + }$ = 7.48) and excellent cycling stability (100 cycles), which would make it a candidate electrode for lithium extraction from salt lakes.

Synthesis of dual-modified Fe-doped and carbon-coated Li4Ti5O12 anode based on industrial H2TiO3 for Li-ion batteries.

Spinel Li4Ti5O12 (LTO) is a promising candidate for lithium-ion battery anodes because of its exceptional stability and safety. However, its extensive application is limited by a high comprehensive cost, poor electronic conductivity, and other inherent defects. This work presents a novel synthesis procedure to synthesize carbon-coated Fe-doped LTO composites through carbon reduction, in the presence of Fe-containing industrial H2TiO3 as the titanium source, and glucose as the carbon source. The presence of the Fe-dopant is confirmed through XRD, with Rietveld refinement and EDS experiments. Results show that Fe2+ replaces a portion of Ti4+ after doping, leading to an increase in the LTO cell parameters and the corresponding cell volume. FLTO/C, presents a capacity of 153.79 mAh g-1 at 10 C, and the capacity decay per cycle is only 0.0074% after 1000 cycles at 5 C. Moreover, EIS experiments indicate that the incorporation of Fe and carbon lowers the charge transfer resistance and improves the diffusion and migration of Li+. Notably, since this preparation process requires no additional Fe source as a raw material, it is simple, cost-effective, and suitable for large-scale production and further application.

Carvacrol protects mice against LPS-induced sepsis and attenuates inflammatory response in macrophages by modulating the ERK1/2 pathway.

Macrophages play an important role in the development of life-threatening sepsis, which is characterized by multiorgan dysfunction, through their ability to produce inflammatory cytokines. Carvacrol is a phenolic compound that has been confirmed to possess strong anti­inflammatory activity. In this study, we mainly investigated the effect of carvacrol on lipopolysaccharide (LPS)-induced macrophage proinflammatory responses and endotoxic shock. The results showed that carvacrol significantly reduced mouse body weight loss and ameliorated pathological damage to the liver, lung, and heart under LPS-induced sepsis. Carvacrol attenuated inflammatory responses by inhibiting the LPS-induced production of inflammatory cytokine interleukin-6 (IL-6) in vivo and in vitro. Mechanistically, carvacrol inhibited IL-6 production mainly through the ERK1/2 signalling pathway in macrophages. Furthermore, carvacrol improved the survival of septic mice. This study sheds light on the role of carvacrol in the pathogenesis of LPS-induced sepsis, and thus, its potential in treating sepsis patients may be considered.

Structural evolution of metatitanic acid and iron removal during hydrolysis of industrial TiOSO4 solution.

The ferrous ion content of metatitanic acid affected the whiteness, purity and applications of TiO2, controlled by the hydrolysis conditions and metatitanic acid structure. The structural evolution of metatitanic acid and ferrous ion removal was investigated by hydrolyzing the industrial TiOSO4 solution. The hydrolysis degree was conformed to Boltzmann model with good fitting. TiO2 content of metatitanic acid gradually increased as hydrolysis proceeding due to its stronger compact structure and weaker colloidal property, caused by the aggregation and adjustment of the precipitated particles. At lower TiOSO4 concentration, the crystal size increased significantly, lattice strain decreased, and average particle size constantly adjusted and reduced. The micropores and mesopores were mainly formed by aggregating and stacking of primary agglomerate particles, bonded and filled with sulfate and hydroxyl. The ferrous ion content decreased linearly with the increase of TiO2 content, and reducing moisture content of metatitanic acid was an effective way to reduce Fe content. This would save more water and energy consumption, help to improve the clean production level of TiO2.

Hierarchical Ti-MOF Microflowers for Synchronous Removal and Fluorescent Detection of Aluminum Ions.

Bifunctional luminescence metal-organic frameworks with unique nanostructures have drawn ongoing attention for simultaneous determination and elimination of metal ions in the aqueous environment, but still remain a great challenge. In this work, three-dimensional hierarchical titanium metal-organic framework (Ti-MOF) microflowers were developed by a secondary hydrothermal method for not only highly sensitive and selective detection of Al(III), but also simultaneously efficient decontamination. The resulting Ti-MOF microflowers with a diameter of 5-6 µm consisted of nanorods with a diameter of ∼200 nm and a length of 1-2 µm, which provide abundant, surface active sites for determination and elimination of Al(III) ions. Because of their substantial specific surface area and superior fluorescence characteristics, Ti-MOF microflowers are used as fluorescence probes for quantitative determination of Al(III) in the aqueous environment. Importantly, the specific FL enhancement by Al(III) via a chelation-enhanced fluorescence mechanism can be utilized for selective and quantitative determination of Al(III). The Al(III) detection has a linear range of 0.4-15 µM and a detection limit as low as 75 nM. By introducing ascorbic acid, interference of Fe(III) can be avoided to achieve selective detection of Al(III) under various co-existing cations. It is noteworthy that the Ti-MOF microflowers exhibit excellent adsorption capacity for Al(III) with a high adsorption capacity of 25.85 mg g-1. The rapid adsorption rate is consistent with a pseudo-second order kinetic model. Ti-MOF is a promising contender as an adsorbent and a fluorescent chemical sensor for simultaneous determination and elimination of Al(III) due to its exceptional water stability, high porosity, and intense luminescence.

Neoflavonoids from the heartwood of Dalbergia melanoxylon.

Three new neoflavonoids, named (1S,8R,9S)-1,5-dihydroxy-4,12-dimethoxy-8-vinyl-tricyclo[7.3.1.02,7]trideca-2,4,6,11-tetraen-10-one (1), 2,5,2',5'-tetrahydroxy-4-methoxybenzophenone (2) and 2,5,3'-trihydroxy-4-methoxybenzophenone (3), were isolated from the heartwood of Dalbergia melanoxylon. Their structures were established by spectroscopic methods, including UV, IR, HRMS, 1 D and 2 D-NMR. Compounds 1-3 were evaluated for inhibitory activity against three fungal strains Candida albicans, Mucor ramosissimus, Saccharomycopsis fermentans and seven bacterial strains Shigella dysenteriae, Salmonella enteri, Bacillus cereus, Staphylococcus epidermidis, Bacillus sphaericus, Staphylococcus aureus, Escherichia coli using the broth dilution method. However, none of compounds 1-3 showed potential antimicrobial activities in vitro.

Immobilization-free electrochemical DNA sensor based on signal cascade amplification strategy.

The development of convenient and efficient strategies without using complex nanomaterials or enzymes for signal amplification is very important for bioanalytical applications. Herein, a novel electrochemical DNA sensor was developed by harnessing the signal amplification efficiency of catalytic hairpin assembly (CHA) and a brand-new signal marker tetraferrocene. The prepared sensor had both ends of the probe H2 labeled with tetraferrocene; both ends have a large number of unhybridized T bases, which cause tetraferrocene to move closer to the electrode surface, generating a high-efficiency amplification signal. In the presence of target DNA, it induced strand exchange reactions promoting the formation of double-stranded DNA and recycling of target DNA. Under optimal conditions, the sensor showed a good linear correlation between the peak currents and logarithm of target DNA concentrations (ranging from 0.1 fM to 0.3125 pM) with a detection limit of 0.06 fM, which is obtained by a triple signal-to-noise ratio. Additionally, the prepared sensor possesses excellent selectivity, reproducibility, and stability, demonstrating efficient and stable DNA detection methodology.

Transcriptional responses of Daphnis nerii larval midgut to oral infection by Daphnis nerii cypovirus-23.

BACKGROUND: Daphnis nerii cypovirus-23 (DnCPV-23) is a new type of cypovirus and has a lethal effect on the oleander hawk moth, Daphnis nerii which feeds on leave of Oleander and Catharanthus et al. After DnCPV-23 infection, the change of Daphnis nerii responses has not been reported. METHODS: To better understand the pathogenic mechanism of DnCPV-23 infection, 3rd-instar Daphnis nerii larvae were orally infected with DnCPV-23 occlusion bodies and the transcriptional responses of the Daphnis nerii midgut were analyzed 72 h post-infection using RNA-seq. RESULTS: The results showed that 1979 differentially expressed Daphnis nerii transcripts in the infected midgut had been identified. KEGG analysis showed that protein digestion and absorption, Toll and Imd signaling pathway were down-regulated. Based on the result, we speculated that food digestion and absorption in insect midgut might be impaired after virus infection. In addition, the down-regulation of the immune response may make D. nerii more susceptible to bacterial infections. Glycerophospholipid metabolism and xenobiotics metabolism were up-regulated. These two types of pathways may affect the viral replication and xenobiotic detoxification of insect, respectively. CONCLUSION: These results may facilitate a better understanding of the changes in Daphnis nerii metabolism during cypovirus infection and serve as a basis for future research on the molecular mechanism of DnCPV-23 invasion.

[Research advances in drug resistance mechanisms of bacterial biofilm and natural drug intervention].

Drug resistance resulting from bacterial biofilms can invalidate antibacterial agents. Therefore,eradicating bacterial biofilms to reverse drug resistance is a hotspot in the pharmaceutical research. In recent years,numerous studies have revealed the complicated mechanism of bacterial biofilm formation and strong drug resistance with multiple influential factors involved. This paper gives a comprehensive review on the process of biofilm formation and intervention by natural drugs,which can provide some reference and evidence for the following studies.

The Hypolipidemic Effect of Dalbergia odorifera T. C. Chen Leaf Extract on Hyperlipidemic Rats and Its Mechanism Investigation Based on Network Pharmacology.

OBJECTIVE: The aim of this study was to explore the hypolipidemic effect and mechanism of Dalbergia odorifera T. C. Chen leaf extract. METHODS: The hypolipidemic effect of D. odorifera leaf extract was investigated using a hyperlipidemic rat model. Then, its mechanism was predicted using network pharmacology methods and verified using western blotting. RESULTS: Compared with the levels in the model group, the serum levels of triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) decreased significantly, whereas the serum level of high-density lipoprotein cholesterol (HDL-C) increased dramatically after treatment with the extract. The degrees of hepatocyte steatosis and inflammatory infiltration were markedly attenuated in vivo. Then, its hyperlipidemic mechanism was predicted using network pharmacology-based analysis. Thirty-five key targets, including sterol regulatory element-binding protein cleavage-activating protein (SCAP), sterol regulatory element-binding protein-2 (SREBP-2), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), low-density lipoprotein receptor (LDLR), and ten signaling pathways, were associated with hyperlipidemia. Finally, it was verified that the extract downregulated the protein levels of SCAP, SREBP-2, and HMGCR, and upregulated protein levels of LDLR. CONCLUSION: These findings provided additional evidence of the hypolipidemic effect of D. odorifera leaf extract.

Characterization and Optimization of Elastomeric Electrodes for Dielectric Elastomer Artificial Muscles.

Dielectric elastomer actuators (DEAs) are an emerging type of soft actuation technology. As a fundamental unit of a DEA, the characteristics of compliant electrodes play a crucial role in the actuation performances of DEAs. Generally, the compliant electrodes can be categorized into uncured and cured types, of which the cured one commonly involves mixing conductive particles into an elastomeric matrix before curing, thus demonstrating a better long-term performance. Along with the increasing proportion of conductive particles, the electrical conductivity increases at the cost of a stiffer electrode and lower elongation at break ratio. For different DEA applications, it can be more desirable to minimize the electrode stiffness or to maximize its conductivity. In examination of the papers published in recent years, few works have characterized the effects of elastomeric electrodes on the outputs of DEAs, or of their optimizations under different application scenarios. In this work, we propose an experimental framework to characterize the performances of elastomeric electrodes with different formulas based on the two key parameters of stiffness and conductivity. An optimizing method is developed and verified by two different application cases (e.g., quasi-static and dynamic). The findings and the methods developed in this work can offer potential approaches for developing high-performance DEAs.

A homogeneous electrochemical DNA sensor on the basis of a self-assembled thiol layer on a gold support and by using tetraferrocene for signal amplification.

An unmodified electrochemical biosensor has been constructed, which can directly detect DNA in homogeneous solution. The synthesized new compound tetraferrocene was used for signal amplification. The dual-hairpin probe DNA was tagged with a tetraferrocene at the 3' terminal and a thiol at the 5' terminal. Without being hybridized with target DNA, the loop of probe prevented the thiol from contacting the exposed gold electrode surface with an applied potential. After hybridization with the target DNA, the loop-stem structure of the probe was opened, which led to the formation of the hairpin DNA structure. Afterwards, the thiol easily contacted the electrode and accomplished potential-assisted Au-S self-assembly. Its current signal depends on the concentration of target DNA in the 1.8 × 10-13 to 1.8 × 10-9 M concentration range, and the detection limit is 0.14 pM. The technique is a meaningful study because of its high selectivity and sensitivity. Graphical abstract Schematic diagram of the electrochemical DNA sensor operation. Target DNA and probe DNA hybridization, resulting in the disappearance of the steric hindrance of the probe stem ring. A higher signal was generated when tetraferrocene reached the electrode. The electrochemical signals were determined by differential voltammetric pulses (DPV).

A sensitive homogenous aptasensor based on tetraferrocene labeling for thrombin detection.

In this work, a novel homogeneous electrochemical aptasensor based on electrically assisted bond and tetraferrocene signal amplification was constructed for thrombin detection. Importantly, modification of the electrode is not necessary for this sensor, requiring only the construction of a simple and efficient probe. In addition, a brand new signal marker-tetraferrocene, containing four ferrocene molecules, was employed as a label to the terminal position of the probe. Compared with a single ferrocene moiety, tetraferrocene possesses a larger amplification signal for rapid detection of thrombin. In the detection of thrombin, the selected aptamer probe with a stem-loop structure was labeled with tetraferrocene at the 3' terminal and thiol at the 5' terminal, respectively. Confinement of the thiol to the stem-loop structure of the probe, the ability of thiol to reach the surface of electrode lossed even with the aid of the applied potential. However, upon treatment with the target protein of thrombin the stem-loop structure opened, promoting rapid attachment of the thiol group to the electrode interface generating Au-S self-assembly with the action of potential-assistance. The electrochemical signal of tetraferrocene could be measured by differential pulse voltammetry (DPV), which was subsequently used for target quantitative detection. This strategy displayed a detection limit as low as 0.126 pM, and an inherently high specificity for the detection of a single mismatch. Moreover, it exhibited advanced specificity against common interfering proteins.

Multi-signal amplification electrochemical DNA biosensor based on exonuclease III and tetraferrocene.

Homogeneous electrochemical DNA biosensors' unique qualities have been of great interest to researchers, mainly due to their high recognition efficiency in solutions. However, the processes of introducing additional markers and extra operations to obtain a signal are tedious and time consuming, which limits their overall potential applications. Herein, a novel tetraferrocene was synthesized and used as a homogeneous electrochemical DNA biosensor probe label. It contains four ferrocene units, which provide greater signaling potential compared to monoferrocene. Furthermore, the target DNA triggers the digestion of the double hairpin DNA probe with the aid of exonuclease III, promoting short single stranded DNA probe formation. With the combination of the incorporated tetraferrocene labeled short DNA probe strands and graphene's ability to adsorb single stranded DNA, the hybridization process can produce an electrode signal provided by tetraferrocene. A low detection limit of 8.2 fM toward target DNA with excellent selectivity was achieved. The proposed sensing system avoids tedious and time-consuming steps of DNA modification, making the experimental processes simpler and convenient. The advantages of high sensitivity, selectivity and simple operation make this strategy applicable to DNA detection.

Highly sensitive host-guest mode homogenous electrochemical thrombin signal amplification aptasensor based on tetraferrocene label.

The development of sensitive and convenient detection methods to monitor thrombin without the use of enzymes or complex nanomaterials is highly desirable for the diagnosis of cardiovascular diseases. In this article, tetraferrocene was first synthesized and then a sensitive and homogeneous electrochemical aptasensor was developed for thrombin detection based on host-guest recognition between tetraferrocene and ß-cyclodextrin (ß-CD). In the absence of thrombin, the double stem-loop of thrombin aptamer (TBA) prevented tetraferrocenes labeled at both ends from entering the cavity of ß-CD deposited on gold electrode surface. After binding with thrombin, the stem-loop structure of TBA opened and transformed into special G-quarter structure, forcing tetraferrocene into the cavity of ß-CD. As a result, thrombin allowed eight ferrocene molecules to reach the gold electrode surface, greatly amplifying the response signal. The obtained aptasensors showed dynamic detection range from 4 pM to 12.5 nM with detection limit around 1.2 pM. Overall, the results indicate that the proposed aptasensors are promising for future rapid clinical detection of thrombin and development of signal amplification strategies for detection of various proteins.

Two new compounds from the heartwood of Dalbergia melanoxylon.

A new neoflavonoid, named S(+)-3'-hydroxy-4',2,4,5-tetramethoxydalbergiquinol (1), and a new benzofuran, named (2S,3S)-5-hydroxy-6-methoxy-3-methyl-2-(4'-hydroxyphenyl)-2,3dihydrobenzofuran (4), together with two known neoflavonoids, were isolated from the heartwood of Dalbergia melanoxylon. Their structures were elucidated by a combination of spectroscopic methods and comparison with the literature. Compounds 1-4 were evaluated for inhibitory activity against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 6538, Salmonella enteri CMCC 50041 and Candida albicans ATCC 289065, which all exhibited inactive or weak activity.

The anti-diabetic activities, gut microbiota composition, the anti-inflammatory effects of Scutellaria-coptis herb couple against insulin resistance-model of diabetes involving the toll-like receptor 4 signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria-coptis herb couple (SC) is one of the well-known herb couples in many traditional Chinese compound formulas used for the treatment of diabetes mellitus (DM), which has been used to treat DM for thousands of years in China. AIM OF THE STUDY: Few studies have confirmed in detail the anti-diabetic activities of SC in vivo and in vitro. The present investigations aimed to evaluate the anti-diabetic activity of SC in type 2 diabetic KK-Ay mice and in RAW264.7 macrophages to understand its possible mechanism. MATERIALS AND METHODS: High-performance liquid chromatography with ultraviolet detection (HPLC-UV) and LC-LTQ-Orbitrap Pro mass spectrometry were used to analyze the active ingredients of SC extracts and control the quality. A type 2 diabetic KK-Ay mice model was established by high-fat diet. Body weight, fasting blood glucose levels, fasting blood insulin levels, glycosylated hemoglobin and glycosylated serum protein were measured. The effects of SC on total cholesterol (TC), high-density lipoprotein (HDL) and triglyceride (TG) levels were examined. The lipopolysaccharide (LPS), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) levels were measured. Gut microbial communities were assayed by polymerase chain reaction (PCR) and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) methods. The expressions of Toll-like receptor 4 (TLR4) and MyD88 protein in the colons were measured by western blot. In RAW264.7 macrophages, IL-6, TNF-α, TLR4 and MyD88 protein levels were measured by enzyme-linked immunosorbent assay (ELISA) kits or western blot, and the mRNA expression of IL-6, TNF-α and TLR4 was examined by the real time PCR. RESULTS: The present results showed that the SC significantly increased blood HDL and significantly reduced fasting blood glucose, fasting blood insulin, glycosylated hemoglobin, glycosylated serum protein, TC, TG, LPS, IL-6 and TNF-α levels (P < 0.05 or P < 0.01) in type-2 diabetic KK-Ay mice. Furthermore, SC could regulate the structure of intestinal flora. Additionally, the expressions of TLR4 and MyD88 protein in the colons were significantly decreased in the model group (P < 0.05 or P < 0.01). However, SC had no significant effect on weight gain. In RAW264.7 macrophages, SC containing serum (SC-CS) (5%, 10% and 20%) significantly decreased IL-6, TNF-α, TLR4 and MyD88 protein levels and the mRNA expression of IL-6, TNF-α and TLR4 (P < 0.05 or P < 0.01). CONCLUSIONS: The anti-diabetic effects of SC were attributed to its regulation of intestinal flora and anti-inflammation involving the TLR4 signaling pathway. These findings provide a new insight into the anti-diabetic application for SC in clinical settings and display the potential of SC in the treatment of DM.

Mechanism and Parameter Optimization in Grinding and Polishing of M300 Steel by an Elastic Abrasive.

In order to achieve high quality polishing of a M300 mold steel curved surface, an elastic abrasive is introduced in this paper and its polishing parameters are optimized so that the mirror roughness can be achieved. Based on the Preston equation and Hertz Contact Theory, the theoretical material removal rate (MRR) equation for surface polishing of elastic abrasives is obtained. The effects of process parameters on MRR are analyzed and the polishing parameters to be optimized are as follows: particle size (S), rotational speed (Wt), cutting depth (Ap) and feed speed (Vf). The Taguchi method is applied to design the orthogonal experiment with four factors and three levels. The influence degree of various factors on the roughness of the polished surface and the combination of parameters to be optimized were obtained by the signal-to-noise ratio method. The particle swarm optimization algorithm optimized with the back propagation (BP) neural network algorithm (PSO-BP) is used to optimize the polishing parameters. The results show that the rotational speed has the greatest influence on the roughness, the influence degree of abrasive particle size is greater than that of feed speed, and cutting depth has the least influence. The optimum parameters are as follows: particle size (S) = #1200, rotational speed (Wt) = 4500 rpm, cutting depth (Ap) = 0.25 mm and feed speed (Vf) = 0.8 mm/min. The roughness of the surface polishing with optimum parameters is reduced to 0.021 µm.

A new pyridine alkaloid from Zingiberis rhizoma.

A new alkaloid, named 2-methoxy-4-(2-(2-pyridine)-ethyl) phenol (1), together with two known compounds, was isolated from Zingiberis rhizoma. Their structures were elucidated on the basis of 1D and 2D NMR spectra and MS spectra. Compound 1 exhibited substantial bioactivity against Canidia albicans ATCC 10231 with a minimum inhibitory concentration of 1.0 mg/mL.

Chemical composition and antioxidant activities of essential oils from different parts of the oregano.

This research was undertaken in order to characterize the chemical compositions and evaluate the antioxidant activities of essential oils obtained from different parts of the Origanum vulgare L. It is a medicinal plant used in traditional Chinese medicine for the treatment of heat stroke, fever, vomiting, acute gastroenteritis, and respiratory disorders. The chemical compositions of the three essential oils from different parts of the oregano (leaves-flowers, stems, and roots) were identified by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity of each essential oil was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and reducing the power test. Among the essential oils from different parts of the oregano, the leaf-flower oils have the best antioxidant activities, whereas the stem oils are the worst. The results of the DPPH free radical scavenging assay showed that the half maximal inhibitory concentration (IC50) values of the essential oils were (0.332±0.040) mg/ml (leaves-flowers), (0.357±0.031) mg/ml (roots), and (0.501±0.029) mg/ml (stems), respectively. Interestingly, the results of reducing the power test also revealed that when the concentration exceeded 1.25 mg/ml, the leaf-flower oils had the highest reducing power; however, the stem oils were the lowest.