Presence of Peroxyradicals in Cigarette Smoke and the Scavenging Effect of Shikonin, a Naphthoquinone Pigment

Nishizawa, Masatoyo; Kohno, Masahiro; Nishimura, Minemitsu; Kitagawa, Akio; Niwano, Yoshimi

doi:10.1248/cpb.53.796

Cited by 34 publications

(24 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We found that lycopene and grape seed extract immediately after incorporating into cigarette filters are able to scavenge up to 90% of free radicals from the gas phase MSC. Such high scavenging capacity ranks these cheap readily available natural compounds among the most efficient reported free radical protectors like haemoglobin and shikonine 8,14 . Yet, in our experiments cigarette filters loaded with studied natural antioxidants lost a noticeable part of their scavenging capacity after a week of storage at room temperature.…”

Section: Figurementioning

confidence: 99%

“…However, due to the cost-ineffectiveness, it has not been successfully commercialized. Another study showed good scavenging efficiency of shikonin, a component of Chinese herbal medicine 8 . In the present study, we report a protocol for introducing common natural antioxidant extracts into the cigarette filter for scavenging gas phase free radicals in cigarette smoke and measurement of the scavenge effect on gas phase free radicals in mainstream cigarette smoke (MCS) using spin-trapping Electron Spin Resonance (ESR) Spectroscopy 1,2,14 .…”

mentioning

confidence: 98%

See 1 more Smart Citation

A Protocol for Detecting and Scavenging Gas-phase Free Radicals in Mainstream Cigarette Smoke

Yu¹,

Dzikovski

Freed

2012

JoVE

View full text Add to dashboard Cite

Cigarette smoking is associated with human cancers. It has been reported that most of the lung cancer deaths are caused by cigarette smoking 5,6,7,12 . Although tobacco tars and related products in the particle phase of cigarette smoke are major causes of carcinogenic and mutagenic related diseases, cigarette smoke contains significant amounts of free radicals that are also considered as an important group of carcinogens 9,10 . Free radicals attack cell constituents by damaging protein structure, lipids and DNA sequences and increase the risks of developing various types of cancers. Inhaled radicals produce adducts that contribute to many of the negative health effects of tobacco smoke in the lung 3 . Studies have been conducted to reduce free radicals in cigarette smoke to decrease risks of the smoking-induced damage. It has been reported that haemoglobin and heme-containing compounds could partially scavenge nitric oxide, reactive oxidants and carcinogenic volatile nitrosocompounds of cigarette smoke 4 . A 'bio-filter' consisted of haemoglobin and activated carbon was used to scavenge the free radicals and to remove up to 90% of the free radicals from cigarette smoke 14 . However, due to the cost-ineffectiveness, it has not been successfully commercialized. Another study showed good scavenging efficiency of shikonin, a component of Chinese herbal medicine 8 . In the present study, we report a protocol for introducing common natural antioxidant extracts into the cigarette filter for scavenging gas phase free radicals in cigarette smoke and measurement of the scavenge effect on gas phase free radicals in mainstream cigarette smoke (MCS) using spin-trapping Electron Spin Resonance (ESR) Spectroscopy 1,2,14 . We showed high scavenging capacity of lycopene and grape seed extract which could point to their future application in cigarette filters. An important advantage of these prospective scavengers is that they can be obtained in large quantities from byproducts of tomato or wine industry respectively 11,13 Video LinkThe video component of this article can be found at https://www.jove.com/video/3406/ Protocol MaterialsAll solvents used in this work were reagent grade. The spin trap, including N-tert-butyl-α-phenylnitrone (PBN) and the standard spin label 2,2,6,6-tetramethyl-1-piperinyoxyl (TEMPO) were obtained from Sigma and were used as supplied. The plant antioxidants were obtained commercially from Swanson, Inc. USA. Preparation of cigarette smoke and analysis of free radicals1. To introduce antioxidants into the filter, the antioxidants pycnogenol and grape seed extract were first dissolved in 95% ethanol, while lycopene was dissolved in acetone. The solvent volumes were different depending on the antioxidant solubility. 2. The amount of antioxidants of 0.4 mg/filter was used. They were then coated with 10 mg of activated carbon. For this purpose activated carbon was stirred for ~12 hrs with the antioxidant solution in anaerobic conditions, filtered and dried under vacuum. 3. Antioxidants were then int...

show abstract

Section: Figurementioning

confidence: 99%

mentioning

confidence: 98%

A Protocol for Detecting and Scavenging Gas-phase Free Radicals in Mainstream Cigarette Smoke

Yu¹,

Dzikovski

Freed

2012

JoVE

View full text Add to dashboard Cite

show abstract

“…2 Despite their reactivity, free radicals have been detected in the vapor phase of cigarette smoke for as long as 5 minutes after combustion. [6][7][8][9][10] This result is due to two specific characteristics of cigarette smoke:…”

Section: Formation Of Radicals In Smokementioning

confidence: 99%

“…They include direct EPR (flow) detection, indirect EPR of spin-trapped species, short-lived radical and stable radical coupling followed by HPLC, LC, fluorescence, GC, MS, or IR methods. [3][4][5][6][7][8][9][10][11] It can be argued that EPR spectroscopy provides the most information about free radicals in a 'single' experiment. This is because the EPR technique is specific (it detects only unpaired electrons), highly sensitive (it can detect free radicals at less than 10 -10 M) and in many cases may give some structural information such as the nature of the atoms closest to the unpaired electron.…”

Section: Detection Of Radicals In Smokementioning

confidence: 99%

Electron paramagnetic resonance investigation of the free radicals in the gas and particulate phases of cigarette smoke using spin-trapping techniques

Ghosh¹,

Ioniță²,

McAughey³

et al. 2008

Arkivoc

View full text Add to dashboard Cite

Free radicals in cigarette smoke have been studied using spin trapping EPR techniques. 2R4F reference cigarettes were smoked using 35 ml puff volumes of 2 seconds duration, once every 60 seconds. The particulate phase of the smoke was separated from the gas phase by passing the smoke through a Cambridge filter pad. For both phases, free radicals were measured and identified. A range of spin-traps was employed: PBN, DMPO, DEPMPO, and DPPH-PBN. In the gas-phase, short-lived carbon-and oxygen-centered radicals were identified; the ratios between them changed during the smoking runs. For the first puffs, C-centered radicals predominated while for the later puffs, O-centered radicals were mainly observed. The particulate phase and the 'tar' were studied as well.

show abstract

“…18,19 Previous work showed that carbon-and oxygen-centred radicals are mainly formed in the gas phase smoke, while the particulate phase contains semiquinone radicals. [18][19][20][21][22][23][24] As far as the authors are aware, there have been no published studies of free radical behaviour in cigarette smoke on a puff-by-puff basis. Different spin-traps have different selectivities towards radical capture.…”

Section: Introductionmentioning

confidence: 99%

Electron spin resonance study of puff-resolved free radical formation in mainstream cigarette smoke

Ghosh¹,

Liu²,

Ioniță³

2009

Arkivoc

View full text Add to dashboard Cite

Puff-by-puff resolved gas phase free radicals were measured in mainstream smoke from Kentucky 2R4F reference cigarettes using ESR spectroscopy. Three spin-trapping reagents were evaluated: PBN, DMPO and DEPMPO. Two procedures were used to collect gas phase smoke on a puff-resolved basis: i) the accumulative mode, in which all the gas phase smoke up to a particular puff was bubbled into the trap (i.e., the 5 th puff corresponded to the total smoke from the 1 st to 5 th puffs). In this case, after a specified puff, an aliquot of the spin trap was taken and analysed; or, ii) the individual mode, in which the spin trap was analysed and then replaced after each puff. Spin concentrations were determined by double-integration of the first derivative of the ESR signal. This was compared with the integrals of known standards using the TEMPO free radical. The radicals trapped with PBN were mainly carbon-centred, whilst the oxygen-centred radicals were identified with DMPO and DEPMPO. With each spin trap, the puff-resolved radical concentrations showed a characteristic pattern as a function of the puff number. Based on the spin concentrations, the DMPO and DEPMPO spin traps showed better trapping efficiencies than PBN. The implication for gas phase free radical analysis is that a range of different spin traps should be used to probe complex free radical reactions in cigarette smoke.

show abstract

Presence of Peroxyradicals in Cigarette Smoke and the Scavenging Effect of Shikonin, a Naphthoquinone Pigment

Cited by 34 publications

References 21 publications

A Protocol for Detecting and Scavenging Gas-phase Free Radicals in Mainstream Cigarette Smoke

A Protocol for Detecting and Scavenging Gas-phase Free Radicals in Mainstream Cigarette Smoke

Electron paramagnetic resonance investigation of the free radicals in the gas and particulate phases of cigarette smoke using spin-trapping techniques

Electron spin resonance study of puff-resolved free radical formation in mainstream cigarette smoke

Contact Info

Product

Resources

About