Presence of peroxyradicals in cigarette smoke and the scavenging effect of shikonin, a naphthoquinone pigment

Using a new method having been developed for the purpose of quantitative determination for peroxyradicals, the presence of peroxyradicals was proved in cigarette smoke. In brief, peroxyradicals in cigarette smoke were measured by ESR spectrometry coupled to non-reductive scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH). As a result, peroxyradicals were found to be major reactive oxygen species (ROS) since the concentration of peroxyradicals recovered from cigarette smoke was much higher than that of any of other ROS (superoxide and hydroxyl radical) and nitric oxide. Furthermore, several antioxidants (ascorbic acid, reduced glutathione, epigallocatechin gallate, shikonin) were examined for scavenging activity against peroxyradicals in the cigarette smoke. Among them shikonin alone exerted the scavenging activity, suggesting that shikonin is promising antioxidant for cigarette filters because of its effectiveness against broad range of ROS including peroxyradicals, heat resistance, nonvolatility and high affinity to the filter.     

Scavenging Effects of Plant Antioxidants on Gas-Phase Free Radicals in Mainstream Cigarette Smoke

Cigarette smoke contains free radicals that are considered to be a major group of carcinogens. In the present study, we used plant antioxidants to treat cigarette filters for scavenging gas phase free radicals in cigarette smoke. The scavenging activities of four antioxidants against gas phase free radicals were analyzed using an improved spin trap protocol. The scavenging rates ranked as lycopene > grape seed extract > pycnogenol > tomato powder. A scavenging rate of 62% (p < 0.001) was obtained from the lycopene treatment. The use of plant antioxidants as potential scavengers for reducing free-radicals in cigarette smoke is discussed.     

Anti-photoaging activity and inhibition of matrix metalloproteinase (MMP) by marine red alga,Corallina pilulifera methanol extract

Matrix metalloproteinases (MMPs), a key component in photoaging of the skin due to exposure to ultraviolet A, appear to be increased by UV-irradiation-associated generation of reactive oxygen species (ROS). In this study, the alga Corallina pilulifera methanol (CPM) extract has been shown to exert a potent antioxidant activity and protective effect on UVA-induced oxidative stress of human dermal fibroblast (HDF) cell. Antioxidant evaluated by various antioxidant assays. These include reducing power, total antioxidant, DPPH radical scavenging, hydroxyl radical scavenging and protective effect on DNA damage caused by hydroxyl radicals generated. Further, the ROS level was detected using a fluorescence probe, 2′,7′-dichlorofluorescein diacetate (DCFH-DA), which could be converted to highly fluorescent dichlorofluorescein (DCF) with the presence of intracellular ROS on HT-1080 cells. Those various antioxidant activities were compared to standard antioxidants such as α-tocopherol. In addition, the in vitro activities of MMP-2 and MMP-9 in HDF cell were inhibited by C. pilulifera methanol extract dose dependently by using gelatin zymography method. The results obtained in the present study suggested that the C. pilulifera methanol extract may be a potential source of natural anti-photoaging.     

Molecularly imprinted polymers on a silica surface for the adsorption of tobacco‐specific nitrosamines in mainstream cigarette smoke

Tobacco‐specific nitrosamines are one of the most important groups of carcinogens in tobacco products. Using adsorbents as filter additives is an effective way to reduce tobacco‐specific nitrosamines in cigarette smoke. Molecularly imprinted polymers (MIPs) using nicotinamide as template were grafted on the silica gel surface to obtain MIP@SiO₂ and employed as filter additives to absorb tobacco‐specific nitrosamines in mainstream cigarette smoke. Four milligrams of MIP@SiO₂ per cigarette was added to the interface between filter and tobacco rod to prepare a binary filter system. The mainstream smoke was collected on an industry‐standard Cambridge filter pad and extracted with ammonium acetate aqueous solution before analysis. Compared to the cigarette smoke of the control group, the levels of tobacco‐specific nitrosamines with silica gel and with MIP@SiO₂ were both reduced, and the adsorption rates of N‐nitrosonornicotine, N‐nitrosoanabasine, N‐nitrosoanatabine, and 4‐(methylnitrosamino)‐1‐(3‐pyridine)‐1‐butanone with silica gel and with MIP@SiO₂ were 20.76, 15.32, 18.79, and 18.01%, and 41.33, 34.04, 37.86, and 35.53%, respectively. Furthermore the content of total particle materials in cigarette smoke with silica gel was decreased evidently but showed no observable change with MIP@SiO₂. It indicated MIP@SiO₂ could selectively reduce tobacco‐specific nitrosamines in the mainstream cigarette smoke with no change to the cigarette flavor.     

Toxic Interaction Between Solar Radiation and Cigarette Smoke on Primary Human Keratinocytes

Solar radiation and cigarette smoke are two environmental risk factors known to affect skin integrity. Although the toxic effects of these factors on skin have been widely studied separately, few studies have focused on their interaction. The objective of this study was to evaluate and understand the synergistic harmful effects of cigarette smoke and solar rays on human primary keratinocytes. The keratinocytes were exposed to cigarette smoke extract (CSE) and then irradiated with a solar simulator light (SSL). The viability, as determined by measuring metabolic activity of skin cells, and the levels of global reactive oxygen species (ROS) were evaluated after exposure to CSE and SSL. The combination of 3% CSE with 29 kJ m⁻² UVA caused a decrease of 81% in cell viability, while with 10% to 20% CSE, the cell viability was null. This phototoxicity was accompanied by an increase in singlet oxygen but a decrease in type I ROS when CSE and SSL were combined in vitro. Surprisingly, an increase in the CSE's total antioxidant capacity was also observed. These results suggest a synergy between the two environmental factors in their effect on skin cells, and more precisely a phototoxicity causing a drastic decrease in cell viability.     

Hyphenated HSCCC–DPPH· for Rapid Preparative Isolation and Screening of Antioxidants from Selaginella moellendorffii

A method for rapid preparative isolation and screening of antioxidants has been developed by combining preparative HSCCC with on-line radical scavenging detection by use of DPPH· (1,1-diphenyl-2-picrylhydrazyl) as model radical. The HSCCC effluent was split into two parts. The major part was collected and the rest was introduced, through a switch valve, directly into a reaction coil for on-line evaluation of antioxidant activity. Each of the antioxidants separated by HSCCC reacted postcolumn with the DPPH· solution in methanol and was observed as a negative peak at 517 nm of size corresponding to its antioxidant activity. The on-line method was successfully used for preparative isolation and screening of antioxidant components from an ethyl acetate extract of the traditional Chinese medicine Selaginella moellendorffii. A total of 114.7 mg amentoflavone, 12.4 mg hinokiflavone, 7.2 mg podocarpusflavone A, and 1.1 mg ginkgetin, identified as the main radical scavengers, were obtained with purity of 99.4, 98.6, 98.9, and 99.2%, respectively, as determined by LC, from 1.0 g ethyl acetate extract. Their chemical structures were identified by MS and by UV and NMR spectroscopy.     

罗丹明6G-锰(Ⅱ)-过氧化体系荧光法测定常见油性种子的抗氧化活性

碱性介质中罗丹明6G能产生特征荧光,其最大激发波长和发射波长分别为350 nm和550 nm;Mn2+-H2O2体系在碱性介质中产生的羟自由基可以迅速氧化罗丹明6G使其荧光猝灭,而油性种子的浸提物可以清除羟自由基,从而使溶液的荧光猝灭程度降低,据此建立了测定油性种子抗氧化性的新方法.实验观察到抗氧化剂维生素C和硫脲等在低浓度范围内对羟自由基的清除率与用量呈上升关系,而在大浓度下反而下降.讨论了样品的水、醋酸、乙醇溶剂浸提物对羟自由基的清除效率.用水、醋酸作提取剂,分别测试了7种常见油性种子的抗氧化活性.     

Comparison of the effect of <Emphasis Type="Italic">Pleurotus citrinopileatus</Emphasis> extract and vitamin E on the stabilization properties of camellia oil

We selected Camellia tenuifolia (Hayata) seed oil to compare the effects of mushroom extract and vitamin E on its stabilization properties. Camellia tenuifolia was selected for its higher oil content, but its proportions of unsaturated fatty acids and natural antioxidants as well as its oxidation stability are lower than those of Camellia oleifera oil. Our aim was to improve the oxidation stability, thermal stability, and photodegradation of C. tenuifolia seed oil and then compare the advantages of mixing traditional antioxidant (vitamin E) and mushroom natural antioxidant components (mushroom extract) in the oil. The focus was on the analysis of the effects of Pleurotus citrinopileatus (Singer) extract and vitamin E on the stabilization properties of C. tenuifolia seed oil, which involved some degradation research, such as evaluating the thermal, oxidation, and antioxidant effects as well as the irradiative (pulsed light) stability of the original oil and oil mixed with additives for comparing the differences by differential scanning calorimetry tests and isothermal microcalorimeter (TAM Air) analyses. We determined the effects of stabilization additives vitamin E and various PC extract doses by using pulsed light irradiation (0, 30, and 60 pulses) and found that the 3 mass% PC extract had the best antiphotodegradation characteristics, and the 0.1 mass% vitamin E indicated the outstanding oxidation stability for among all of the additives in this study. Overall, we obtained the following suitable conditions to stabilize camellia oil: addition of vitamin E, addition of 3 mass% PC extract, and a nitrogen atmosphere.     

Phenolic antioxidants identified by ESI-MS from Yerba maté (Ilex paraguariensis) and green tea (Camelia sinensis) extracts

Aqueous extracts of green yerba maté (Ilex paraguariensis) and green tea (Camellia sinensis) are good sources of phenolic antioxidants, as already described in the literature. The subject of this study were organic extracts from yerba maté, both green and roasted, and from green tea. Their phenolic profiles were characterized by direct infusion electrospray insertion mass spectrometry (ESI-MS) and their free radical scavenging activity was determined by the DPPH assay. Organic extracts containing phenolic antioxidants might be used as natural antioxidants by the food industry, replacing the synthetic phenolic additives used nowadays. Ethanolic and aqueous extracts from green yerba maté, roasted yerba maté and green tea showed excellent DPPH scavenging activity (>89%). The ether extracts from green and roasted yerba maté displayed a weak scavenging activity, different from the behavior observed for the green tea ether extract. The main phenolic compounds identified in green yerba maté water and ethanolic extracts were: caffeic acid, quinic acid, caffeoyl glucose, caffeoylquinic acid, feruloylquinic acid, dicaffeoylquinic acid and rutin. After the roasting process two new compounds were formed: caffeoylshikimic acid and dicaffeoylshikimic acid. The ethanolic extracts from yerba maté, both roasted and green, with lower content of phenolic compounds (3.80 and 2.83 mg/mL) presented high antioxidant activity and even at very low phenolic concentrations, ether extract from GT (0.07 mg/mL) inhibited DPPH over 90%.     

Identification and in vitro antioxidant activities of phenolic compounds isolated from Cynoglossum cheirifolium L.

In an extensive search for bioactive compounds from plant sources, the quantitative and qualitative characterisation of the compounds present in Cynoglossum cheirifolium extracts was studied. Total phenolic and flavonoid contents were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined through DPPH^? scavenging activity and Ferric reducing antioxidant power (FRAP). Our study showed that leaves produce more phenolic compounds, followed by flowering aerial part. The butanolic fraction obtained from leaves extract exhibited the highest total phenolics (78.65 ± 3.58 mg GAE/g DW) and flavonoids (22.15 ± 4.66 mg CE/g DW). In contrast, this fraction displayed the highest DPPH^? scavenging ability with IC₅₀ values of 0.06 ± 0.003 mg/mL. The RP-HPLC-PDA analysis of phenolic compounds from leaves of C. cheirifolium lets to identify: rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid, syringic acid, sinapic acid and rutin. The obtained results indicate that this plant represent a valuable source of natural antioxidants.     

Phytochemical and antioxidant properties of some Cassia species

In this study, the antioxidant activity of aqueous and ethanol extracts of four plants from the genus Cassia were evaluated by various antioxidant assays, including ferric reducing antioxidant power (FRAP), DPPH free radical scavenging, metal chelating activity, phosphomolybdenum reducing power, hydrogen peroxide radical scavenging, hydroxyl radical scavenging, deoxyribose degradation and β-carotene bleaching assay. The various antioxidant activities were compared to standard antioxidant such as ascorbic acid. All the extracts showed antioxidant activity in the tested methods. Among the four species, Cassia auriculata has been found to possess highest activity in most of the tested models. In addition to the antioxidant activity, the total phenolics and flavonoids were measured in the extracts. The ethanolic extract exhibited highest phenolics and flavonoid contents and had also shown potent antioxidant activity in comparison to the aqueous extracts. The possible antioxidant mechanism of the ethanol extract can be due to its hydrogen or electron donating and direct free radical scavenging properties. Hence, the ethanol extract represents a source of potential antioxidants that could be used in pharmaceutical industries.     

Dihydromyricetin

A study on the efficiency of bio-based compound as stabilizer for linear low density polyethylene (LLDPE) is reported. A water extract from Ampelopsis grossedentata (Dihydromyricetin) is used. Its stabilizing activity is compared with two commercial phenolic antioxidants: methyl gallate (MG) and Irganox 1010. Based on the measurement of the oxidation onset temperature (OOT) of LLDPE/antioxidant samples, it is found that the antioxidant ability of the three kinds of antioxidants is in the following order: DMY > 1010 > MG. The antioxidant ability and thermal decomposition activation energy (E _a) of antioxidants are further examined by thermal gravimetric analysis. The effects of water extraction on the migration resistance of LLDPE/antioxidants are also evaluated by monitoring the OOT change, demonstrating that DMY retained high stability against migration.     

Ethanolic extracts of Moringa oleifera Lam.

This paper reports the evaluation of the antioxidant potential of the ethanolic extracts of the leaves (EL), flowers (EF), seed pods (EP) and seeds (ES) from Moringa oleifera Lam. The antioxidant potential was assessed, upon the addition of the extracts to fish oil, by means of the total extractable phenol content (TEP), the DPPH^· free radical scavenging efficiency and using pressurized differential scanning calorimetry (P-DSC). The results of TEP and DPPH^· showed that the ES extract does not present a potential to be used as an antioxidant additive, and it was thus discarded from the remaining analyses. Thus, the following treatments were prepared: pure fish oil, fish oil with BHT (100 mg kg^?1), fish oil with TBHQ (100 mg kg^?1) and fish oil with EL, EF and EP—all at the concentration of 100 mg kg^?1, in relation to the total extractable phenolics contained in each one of the extracts. The leaf and flower extracts displayed a protecting effect, with an increase in about 20 and 11 % of the OIT values, respectively. However, such protection was smaller than that conferred by the synthetic antioxidants utilized. As for the thermal analysis results, it was noticed that EL presented the highest thermal stability among the extracts.     

LC–DAD/ESI–MS/MS characterization of phenolic constituents in Rosa canina L. and its protective effect in cells

In an aim to prove the efficiency of polyphenols of Rosa canina fruits in promoting human health. A methanolic extract of R. canina fruits was prepared by successive maceration with solvents of increasing polarity. The polyphenol composition was analyzed by HPLC–DAD–ESI–MS. The biological activity of this extract on SH-SY5Y cells and HepG2 cells was then studied. The antioxidant activity was tested by various in vitro tests such as DPPH-radical-scavenging activity, FRAP assay, hydroxyl radical scavenging assay and total antioxidant capacity. The subacute toxicity of R. canina was tested on female rats by repeated intraperitoneal administration of various doses. The phenolic profiles showed 25 antioxidants distributed into three classes of phenolic compounds: glycosylated and agglomerated flavonoids/isoflavonoids, tannins and phenanthrenes. Qualitative phytochemical analyses showed that this extract lacks alkaloids. The methanolic extract of R. canina fruits has a total antioxidant capacity of 82.69 ± 1.18 μg EAA/mg of methanol extract and the IC₅₀ of the methods used is in the following increasing order: FRAP assay (61.88 μg/ml), then hydroxyl radical scavenging assay (67.45 μg/ml) and then DPPH radical-scavenging activity (129.81 μg/ml). The extract of R. canina did not cause any phenotypic signs of toxicity or mortality during and after treatment. The LD₅₀ was >5,000 mg/kg, hence, R. canina was considered nontoxic. An in vivo study proved the protective effect of R. canina against cardiac and hepato-renal toxicities. These results drew the importance of a healthy diet, where diets rich in R. canina fruits can be used as a rich natural source of antioxidants and anticarcinogenic phenolic compounds.     

The characterisation and evaluation of activated carbon in a cigarette filter

Cigarette smoke is an ever changing and extremely complex mixture of over 5000 chemicals. When the cigarette burns, thousands of chemical substances are generated, and these are distributed between the gas phase and the particles which constitute the smoke aerosol. Activated carbon when used in a filter can selectively remove a number of the vapour phase compounds to varying degrees of efficiency. Carbons of different activities (50–60% CTC and 90–100% CTC) have been characterised using nitrogen adsorption and also the sorption of a number of different vapours with different properties, using a dynamic gravimetric adsorption technique. Surface areas, pore volumes, diffusivities and heats of adsorption were calculated using nitrogen, benzene, heptane, ethyl acetate and water as the probe molecules. Smoke chemistries were measured using a screening approach on the characterised carbons as filter additives. It was seen that the higher activity carbon results in increased retention in the majority of the measured vapour phase smoke constituents.     

Antioxidant activities and bioactive compounds of five Jalopeno peppers (Capsicum annuum) cultivars

The present study was designed to evaluate the contents of different antioxidants compounds and their antioxidant activities in Jalopeno peppers (Capsicum annuum) cultivars (El Dorido, Grande, Tula, Sayula and El Rey) extracts. Free radical scavenging activity of Grande was recorded as high as 87% followed by El Dorido (83%). Results of reducing power (Fe³⁺ to Fe²⁺) showed that Grande (0.85%) and El Dorido (0.81%) fruit extract absorbance value were close to synthetic antioxidant BHT (0. 97%) obtained at100 μg/mL. The results showed that total phenolic content of El Dorido and Grande were significantly higher compared to other Jalapeno pepper. Results indicated strong and positive correlation between antioxidant activity and carotenoids content (r = 0.75), vitamin C (r = 0.78) and total capsaicinoids (r = 0.84), respectively. The results of the antioxidant activity assays showed that the El Dorido and Grande had strongest antioxidant activity compared to other peppers cultivars in this study.     

Improved real-time puff-by-puff GC-MS system for whole smoke analysis

An automated puff-by-puff mainstream smoke (MSS) system is developed to monitor real-time whole smoke in mainstream cigarette smoke using gas chromatography (GC)-mass spectrometry (MS). The whole-smoke analysis is based on automated sample collection and injection into the GC-MS system. The important feature of this system is the real-time rapid analysis that is simple, sensitive, precise, flexible, and exhibits low carryover of volatile and semivolatile smoke constituents. The system is equipped with an automated sampling and switching valve and a smoking machine. The key improvements of the system, as compared with current and alternative methodologies, include minimizing variations caused by operator sampling techniques, the real-time analysis of MSS, the detection of flavorants in MSS from a single puff of cigarette smoke, the ability to analyze numerous smoke constituents from either whole smoke or the gas phase of a single puff, the ability to monitor a few selected smoke constituents in whole smoke using multiple puffs, and its good feasibility compared with solvent extraction and impinger trapping procedures for volatile organic compounds in MSS. System configuration and sampling methodologies are described. Sensitivity, flexibility, precision, feasibility, carryover, and applications of the system are discussed.     

全自动固相萃取-气相色谱-串联质谱法测定卷烟主流烟气中的3种多环芳烃

以全自动固相萃取技术净化主流烟气萃取液,建立了卷烟主流烟气中苯并［a］芘、苯并［a］蒽和屈艹 3种多环芳烃的气相色谱-串联质谱(GC-MS/MS)测定方法。以吸烟机抽吸卷烟,并以剑桥滤片捕集卷烟主流烟气,然后以含氘代苯并［a］芘内标的环己烷溶液萃取滤片,萃取液经全自动固相萃取仪净化后以GC-MS/MS分离检测。结果表明,苯并［a］芘、苯并［a］蒽和屈艹 的检出限分别为0.05、0.16和0.23 ng/cig,回收率为91.5%～102.1%,相对标准偏差(RSD)均小于5%。该方法的自动化程度高、操作简便、检出限低、重复性好,适用于卷烟主流烟气中苯并［a］芘、苯并［a］蒽 3种多环芳烃释放量的检测。     

HPLC-ESI-MS/MS analysis of phenolics and in vitro antioxidant activity of Epilobium angustifolium L.

The aerial parts of Epilobium plants are widely used as folk medicine and food around the world. The present study was aimed to investigate the antioxidant activities and active chemical constituents from Epilobium angustifolium L. The results revealed that the EtOAc extract, rich in phenolic compounds and flavonoids (16.81 ± 0.67 g GAE/100 g extract and 4.95 ± 0.21 g QE/100 g extract, respectively), possessed significantly antioxidant activities in reducing power, DPPH radical scavenging activity, ABTS radical scavenging activity and highly in inhibiting lipid peroxidation activity. Simultaneously, active fractions F to H from EtOAc extracts showing potent in vitro antioxidant activities also contained high content of total phenolic and flavonoid. Twenty-eight compounds were identified as phenolic compounds and flavonoids by LC-MS/MS. The results illustrate that the E. angustifolium L., which is rich in phenolics, could be used as a natural resource of antioxidant ingredient.