Dimethyl Sulfoxide Extracts Research Articles

Development of a standardized methodology for quantifying total chlorophyll and carotenoids from foliage of hardwood and conifer tree species

Despite the availability of several protocols for the extraction of chlorophylls and carotenoids from foliage of forest trees, information regarding their respective extraction efficiencies is scarce. We compared the efficiencies of acetone, ethanol, dimethyl sulfoxide (DMSO), and N, N-dimethylformamide (DMF) over a range of incubation times for the extraction of chlorophylls and carotenoids using small amounts of unmacerated tissue. Of the 11 species studied, comparable amounts of chlorophyll were extracted by all four solvents from three species and by ethanol and DMF from nine species. In four species, acetone, ethanol, and DMF extracted comparable chlorophyll amounts, while in another two species comparable amounts were extracted by ethanol, DMSO, and DMF. In one species, ethanol extracted significantly greater amounts of chlorophyll compared with all other solvents. The brown coloration of DMSO extracts for some species compromised the calculations of chlorophylls and carotenoids, making DMSO a poor choice. Overall, extraction efficiencies of ethanol and DMF were comparable for analyzing chlorophyll concentrations. However, because DMF is more toxic than ethanol, we recommend ethanol as the better option of these two for chlorophyll extractions. On the other hand, DMF is the most efficient solvent among the four tested for the extraction of carotenoids from these species. The results presented will facilitate the design of multispecies local- and regional-scale ecological studies to evaluate forest health. Additionally, they will enable reliable comparisons of results from multiple laboratories and (or) studies that used different solvents and help validate chlorophyll estimates obtained by remote sensing.

땅강아지(Gryllotalpa orientalis) 추출물의 항산화 및 항염증 활성

동 <TEX>${\cdot}$</TEX> 식물의 추출물은 예로부터 생약으로 많이 이용이 되었는데, 이는 추출물 내에 다양한 생리 활성 물질 및 화합물을 포함 하고 있기 때문이다. 본 연구는 한방에서 누고(樓姑)라고 알려진 땅강아지 추출물에 대한 항산화 활성을 1,1-diphenyl-2-picrylhydrazyl (DPPH)와 ferric reducing ability of plasma (FRAP)활성 실험을 통하여 알아보았다. 땅강아지는 DW, DMSO, 에탄올, 메탄올에 추출하였다. 실험 결과 땅강아지 추출물의 항산화활성은 DPPH radical 소거 활성의 경우 에탄올 추출물에서 가장 높은 활성을 나타났다. FRAP 활성의 경우 DW 추출물에서 가장 높게 나타났으며, 시간에 따른 활성의 증가는 에탄올 추출물에서 가장 높게 나타났다. Cyclooxygenase-2 promoter의 활성 저해는 DMSO와 에탄올 추출물에서 저해활성이 상대적으로 높은 것으로 미루어 보아서 이들 추출물간의 특성을 잘 응용할 경우 항산화 및 항염증에 좋은 생물학적 재료가 될 것으로 판단된다. Tremendous natural product extracts were used as a herb medicine remedy or therapy for centuries. Because these extracts have various biological activities, we examined the effects of Gryllotalpa orientalis extract for anti-oxidant and anti-inflammation activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing ability of plasma (FRAP), hydroxy radical scarvenging and cyclooxygenase-2 promoter assays. Gryllotalpa orientalis extracts were prepared from solvents such as distilled water (DW), dimethyl sulfoxide (DMSO), ethanol and methanol. The results showed that Gryllotalpa orientalis extracts have potent DPPH (methanol extract), FRAP (DW extract) and hydroxy radical scavenging (DW and methanol extracts) activity than any other extracts used. A significant inhibition of cyclooxygenase-2 (Cox-2) promoter activity was detected in the presence of DMSO extract or ethanol extract. Collectively, the present results suggested that Gryllotalpa orientalis extract could be used for anti-oxidant and/or anti-inflammation agent for human or agricultural purposes.

Susceptibility of &lt;i&gt;Aedes aegypti&lt;/i&gt; pupae to neem seed kernal extracts

Laboratory bioassays were conducted to evaluate the pupicidal activity of neem (Azadirachta indica) seed kernel extracts (NSKE) on Aedes aegypti. The neem seed kernel powder was sequentially extracted with hexane, benzene, ethyl acetate, acetone, DMSO, 2-propanol, ethanol, methanol and dstiledwater. Ten concentratons (0.0, 0.25, 0.5, 1.0, 2.0, 4.0, 50, 10.0,15.0 and 20.0%) of the neem extracts were used for the bioassays. Each treatment was replcated five times. Twenty-laboratory strains of Aedes aegypti pupae were exposed to each concentration Pupae were not fed durng the exposure periods. Pupal mortality was assessed after 1 and 24 hoursof exposure. The results of the effects of 1h exposure indicated decreased pupicidal mortality whdecreasing extracts toxicity thus: ethyl acetate (LC 50 = 0.06%) > acetone > (LC 50 = 0.29%) > benzene (LC 50 = 0.82%) > hexane (LC 50 = 3.13%) and propanol (LC 50 = 763%). No pupal mortality was observed with extracts from Dimethyl sulfoxide (DMSO), ethanol, methanol and distilled water. The results of the effect of extract for 24h exposure indicated pupicidal mortality in2-propanol (LC 50 = 0.67%) and ethanol (LC 50 = 1.70%). No pupcida mortality was observed wth hexane, benzene, ethyl acetate, acetone, Dimethylsulfoxide (DMSO), methano and distiled water extracts. The ability of some neem extracts to kill Aedes pupae at relativey low concentrations presents an alternative to the use of synthetic pesticides for control of mosquitoes. This techniqueis environmental friendly, biodegradable, less expensive, and locally available in mosquito endemicarea. Potentials for adoption in mosquito management programmes cannot be overemphasized. Keywords : Azadirachta indica, Aedes aegypti, Pupicidal Animal Research International Vol. 3 (1) 2006 pp. 403-406

Newspapers and newspaper ink contain agonists for the ah receptor.

Ligand-dependent activation of the aryl hydrocarbon receptor (AhR) pathway leads to a diverse array of biological and toxicological effects. The best-studied ligands for the AhR include polycyclic and halogenated aromatic hydrocarbons, the most potent of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, as new AhR ligands are identified and characterized, their structural and physiochemical diversity continues to expand. Our identification of AhR agonists in crude extracts from diverse materials raises questions as to the magnitude and extent of human exposure to AhR ligands through normal daily activities. We have found that solvent extracts of newspapers from countries around the world stimulate the AhR signaling pathway. AhR agonist activity was observed for dimethyl sulfoxide (DMSO), ethanol, and water extracts of printed newspaper, unprinted virgin paper, and black printing ink, where activation of luciferase reporter gene expression was transient, suggesting that the AhR active chemical(s) was metabolically labile. DMSO and ethanol extracts also stimulated AhR transformation and DNA binding, and also competed with [(3)H]TCDD for binding to the AhR. In addition, DMSO extracts of printed newspaper induced cytochrome P450 1A associated 7-ethoxyresorufin-O-deethylase activity in zebrafish embryos in vivo. Although the responsible bioactive chemical(s) remain to be identified, our results demonstrate that newspapers and printing ink contain relatively potent metabolically labile agonists of the AhR. Given the large amount of recycling and reprocessing of newspapers throughout the world, release of these easily extractable AhR agonists into the environment should be examined and their potential effects on aquatic organisms assessed.

A dietary supplement for female sexual dysfunction, Avlimil, stimulates the growth of estrogen-dependent breast tumors (MCF-7) implanted in ovariectomized athymic nude mice

Avlimil, a dietary supplement advertised to ameliorate female sexual dysfunction, is a mixture of eleven herbal components, and some herbal constituents of Avlimil (including black cohosh, licorice, red raspberry, red clover and kudzu) contain phenolic compounds, which are suggested to have estrogenic, anti-estrogenic, or androgenic potential for relieving menopausal symptoms. We hypothesize that Avlimil could modulate the growth of estrogen receptor positive human breast cancer (MCF-7) cells in vitro and in vivo. A dimethylsulfoxide (DMSO) extract of Avlimil (0.001–100 μg Avlimil powder equivalents/mL media) was tested for its estrogenic and anti-estrogenic effects on the growth of MCF-7 cells in vitro. We observed that the DMSO extract of Avlimil at low concentrations (0.1–50 μg/mL media) dose-dependently increased MCF-7 cell proliferation in vitro, and Avlimil DMSO extract at 100 μg/mL inhibited the growth of MCF-7 cells in vitro. Avlimil and some constituents (black cohosh and licorice roots) of Avlimil were fractionated by using sequential solvent extraction (hexane, ethyl acetate, and methanol) and the activities of the fractions were monitored by effects on the growth of MCF-7 cells. Depending on dosage (0.1–100 μg/mL media) both stimulatory and inhibitory effects of the extracts on the growth of MCF-7 cells were observed. The effect of dietary Avlimil at dosages approximating human intake was evaluated using ovariectomized mice implanted with MCF-7 cells. Animals were fed diets containing 500 ppm or 1000 ppm Avlimil for 16 weeks. Dietary Avlimil at 500 ppm stimulated MCF-7 tumors, but Avlimil at 1000 ppm had no apparent effect on the growth of MCF-7 tumors. The observation of stimulated tumor growth in the absence of uterine wet weight gains suggest that estrogenic/anti-estrogenic effects of Avlimil we observed may be dosage- and target tissue-specific and that Avlimil may not be safe for women with estrogen-dependent breast cancer. The different biological effects of fractionated Avlimil components and the different concentration dependencies warrant further compound identification and dose-response studies, especially at recommended intake levels that could have estrogenic effects in women.

Quantitative Analysis of Cotton (Gossypium hirsutum) Lint Trash by Fluorescence Spectroscopy

The presence of cotton plant botanical components, or trash, embedded in lint subsequent to harvesting and ginning is an important criterion in the classification of baled cotton by the U.S. Department of Agriculture Agricultural Marketing Service. The trash particles may be reduced in size to the point that specific trash types are not identifiable by image or gravimetric analysis, and it is desirable to quantify different trash types so that processing lines may be optimized for removal of the most problematic trash to enhance processing performance and cotton lint quality. Currently, there are no methods available to adequately quantify cotton lint trash based on botanical origin. The present work attempts to address this issue through the analysis by fluorescence spectroscopy of dimethyl sulfoxide extracts of mixtures of six botanical trash types. The fluorescence data are subsequently subjected to chemometric analysis. The resulting 6 partial least-squares calibration models obtained from 128 mixtures are demonstrated in the case of leaf and hull to be capable of predicting individual trash component concentrations with a high degree of confidence.

Isolation of Fucoxanthin from the Rhizoid of Laminaria japonica Aresch

Abstract: Fucoxanthin was extracted from the intact rhizoid of Laminaria japonica Aresch with dimethyl sulfoxide (DMSO), and then recovered from the DMSO extract by partitioning into ethyl acetate and subsequent evaporation. Some isolation conditions such as solvent volume and extraction time were screened. The quantity and quality of the extracted fucoxanthin were determined by spectral analysis (absorption spectra and fluorescence emission spectra). The results indicated that: (1) the average total content of fucoxanthin was 122.1 μg in 1 g of fresh L. japonica rhizoid; (2) in comparison with the widely used organic solvent, acetone, DMSO was much more effective for the extraction of fucoxanthin; (3) both DMSO volume and extraction time influenced extraction efficiency such as the recovery rate and purity of fucoxanthin (1 g of fresh L. japonica rhizoid treated with 4 mL DMSO for 60 min, yielded > 88% of the total fucoxanthin with purity 0.63); (4) when (NH4)2SO4 concentration was in the range of 0.5–1.0 mol/L, the pigments rapidly and entirely moved from DMSO into the ethyl acetate phase; (5) the ethyl acetate and DMSO were recycled using a rotary evaporator. (Managing editor: Wei WANG)

Radioprotection of turmeric extracts in bacterial system

The present study investigates the possible role of crude turmeric extracts in radioprotection by a variety of methods. Although curcumin, the main bioactive component of turmeric, has been extensively used in such studies, the efficiency of the crude extracts has been poorly investigated. This study revealed that dimethyl sulfoxide (DMSO) extracts of turmeric produces a significant amount of radioprotection, which is very similar in nature and extent to that imparted by curcumin. Field Inversion Gel Electrophoresis (FIGE) studies also clearly showed the protection offered by turmeric extracts against X-ray induced DNA damage of E. coli WP2s(lambda) cells.

Genotoxicity of airborne particulate matter: the role of cell–particle interaction and of substances with adduct-forming and oxidizing capacity

Exposure to particulate matter (PM) is associated with several health effects including lung cancer. However, the mechanisms of particle-induced carcinogenesis are not fully understood. The main aim of this study was to investigate the genotoxicity of PM in relation to particle–cell interactions and to study the effect of removal of DNA-damaging substances by extraction of PM with different solvents. Genotoxicity was analyzed by means of the comet assay after exposure of cultured human fibroblasts to urban dust particles (SRM 1649). It was found that PM induced DNA damage in a dose-dependent manner and that cells interacting with PM suffered more DNA single-strand breaks relative to other cells. The genotoxicity of PM was significantly reduced after extraction with dichloromethane (DCM), dimethyl sulfoxide (DMSO) and water, but not with acetone and hexane. However, the insoluble particle core still induced DNA single-strand breaks. The extracts were further investigated in cell-free systems. Analysis of aromatic DNA adducts with 32P-HPLC showed that the DMSO and DCM extracts contained most of the DNA-reactive polyaromatic compounds (PACs). Further, the formation of 8-oxo-2′-deoxyguanosine (8-oxodG) upon incubation of the extracts with 2′-deoxyguanosine (dG) showed that the water extract contained most of the oxidizing substances. Thus, the genotoxicity of PM was caused both by adduct-forming PACs and oxidizing substances as well as the insoluble particle-core. This study showed that all these factors together contribute to explaining the mechanisms of PM genotoxicity.

An in vitro study on antimicrobial activity of propolis from Mugla province of Turkey.

Antibacterial and antifungal activities of acetone and dimethyl sulfoxide (DMSO) extracts of 45 different propolis samples from the Mugla province of Turkey were investigated. Antimicrobial activity of propolis varied depending on propolis sample, dosage of propolis, and the extraction solvents for all test microorganisms. Antimicrobial activity of all propolis samples increased with increasing dosage without reaching a plateau at the highest dosage tested. Except for Brucella melitensis, the DMSO extracts of all propolis samples were more active than the acetone extracts of the same samples. For B. melitensis, the acetone extracts of all propolis samples showed greater activity. The most sensitive microorganism to propolis was Shigella sonnei in the gram-negative group and Streptococcus mutans in the gram-positive group. The least sensitive microorganism was Candida albicans. A control test run with standard antibiotics revealed that propolis samples from the Mugla province of Turkey has a similar or greater inhibitory effect on S. mutans, Salmonella typhi, Pseudomonas aeruginosa, S. sonnei, and C. albicans growth.

Determination of polychlorinated biphenyls in ash using dimethylsulfoxide microwave assisted extraction followed by solid-phase microextraction

A procedure for the determination of several coplanar and non coplanar PCBs in ash samples is described. Analytes were extracted from the samples using dimethylsulfoxide (DMSO) under the action of a microwave field, and then they were concentrated on a PDMS-DVB solid-phase microextraction (SPME) fibre using the headspace mode, after water dilution of the DMSO extract. Determinations were carried out using GC–ECD and GC–MS detection. Influences of microwave extraction (solvent volume, temperature and time) and SPME conditions (stirring, kind of SPME fibre, salt and water addition, sampling time and temperature) on the performance of the whole analytical procedure were systematically investigated. Working under optimal conditions quantification limits from 0.2 to 1.5ngg−1 were obtained for all the compounds, except for PCB 209, which could not be consistently extracted from the sample using the proposed conditions.

Petroleum Mineral Oil Refining and Evaluation of Cancer Hazard

Petroleum base oils (petroleum mineral oils) are manufactured from crude oils by vacuum distillation to produce several distillates and a residual oil that are then further refined. Aromatics including alkylated polycyclic aromatic compounds (PAC) are undesirable constituents of base oils because they are deleterious to product performance and are potentially carcinogenic. In modern base oil refining, aromatics are reduced by solvent extraction, catalytic hydrotreating, or hydrocracking. Chronic exposure to poorly refined base oils has the potential to cause skin cancer. A chronic mouse dermal bioassay has been the standard test for estimating carcinogenic potential of mineral oils. The level of alkylated 3-7-ring PAC in raw streams from the vacuum tower must be greatly reduced to render the base oil noncarcinogenic. The processes that can reduce PAC levels are known, but the operating conditions for the processing units (e.g., temperature, pressure, catalyst type, residence time in the unit, unit engineering design, etc.) needed to achieve adequate PAC reduction are refinery specific. Chronic dermal bioassays provide information about whether conditions applied can make a noncarcinogenic oil, but cannot be used to monitor current production for quality control or for conducting research or developing new processes since this test takes at least 78 weeks to conduct. Three short-term, non-animal assays all involving extraction of oil with dimethylsulfoxide (DMSO) have been validated for predicting potential carcinogenic activity of petroleum base oils: a modified Ames assay of a DMSO extract, a gravimetric assay (IP 346) for wt. percent of oil extracted into DMSO, and a GC-FID assay measuring 3-7-ring PAC content in a DMSO extract of oil, expressed as percent of the oil. Extraction with DMSO concentrates PAC in a manner that mimics the extraction method used in the solvent refining of noncarcinogenic oils. The three assays are described, data demonstrating the validation of the assays are shown, and test results of currently manufactured base oils are summarized to illustrate the general lack of cancer hazard for the base oils now being manufactured.

Is dimethylsulfoxide a reliable solvent for extracting chlorophyll under field conditions?

Dimethylsulfoxide (DMSO) appears to be a reliable solvent for extracting chlorophyll (Chl), however, modification of standard methods may be necessary for some species under field conditions. We found that Chl extraction of whole leaf tissue with DMSO incubated at between 25 and 40 degrees C was generally similar to the 80% acetone method, except for one graminoid species that required maceration. There was little effect of incubation temperature or duration of incubation beyond 7 h on extraction efficiency, but DMSO extracts were less stable than acetone extracts during one week of cold storage, especially if they thawed during this period. Since Chl extraction methods may provide variable results, particularly in the field, studies using different solvents should be compared cautiously unless specific methods have been calibrated.

Anticlastogenic effect of S pirulina maxima extract on the micronuclei induced by maleic hydrazide in Tradescantia

The aim of this investigation was to determine if extracts of Spirulina maxima reduce the genotoxic damage induced by maleic hydrazide (MH) using the Tradescantia biosssay. Two types of extracts from the alga were prepared: an aqueous extract with two different concentrations, 100 and 500 mg/ml, and a second one, the extract of a 1% solution of dimethyl sulfoxide (DMSO) which corresponded to 100 mg/ml of the alga. The capacity of MH to induce micronuclei (MN) was initially established by administering 0.005, 0.01, and 0.015 mg/ml of the chemical to the Tradescantia inflorescences, and observing its effect after 24 h. The results of this experiment showed a significant MN increase with the two high concentrations tested, although no dose-response effect was observed. For the anticlastogenic assay, the extracts of Spirulina were applied to the inflorescences alone or immediately before the application of MH (0.01 mg/ml) and the induced MN were observed 24 h later. We found that none of the extracts increased the MN level with respect to the untreated plants; also, that MH more or less doubled the basal micronuclei frequency, and finally, that all tested extracts reduced the genotoxic damage caused by MH. The inhibitory indices obtained for the aqueous extracts (100 and 500 mg/ml) and for the DMSO extract were respectively 59, 85, and 56.3%. These data indicate that Spirulina is an anticlastogenic agent and suggest that it is advisable to extend studies on this matter using other biological models.

Extraction and determination of chlorophylls from moso bamboo (Phyllostachys pubescens) culm

The purpose of this study is to establish a simple and reliable method for bamboo chlorophyll extraction. Chlorophylls in moso bamboo (Phyllostachys pubescens) epidermis were extracted with acetone, DMF (N,N-dimethylformamide) and DMSO (dimethyl sulfoxide) using three methods, including ultrasonics, centrifugation and grinding. Ultraviolet-visible spectrometry was then used to evaluate the efficiency of these extraction methods. It was also used to quantitatively analyze the extracted chlorophylls. The results revealed that the extraction efficiency of epidermis chlorophylls is related to the size of bamboo culm meal, solvent types, and the method of extraction and filtration. A fast and reliable extraction method was developed. It extracts chlorophylls from bamboo culm meal (<0.7 mm) using an acetone bath in ultrasonics for 3 min and followed by centrifugal filtration. This extraction procedure has been proven to be easy to use and also highly reproducible. Chlorophylls in acetone showed the best stability, followed by DMF and then DMSO. In a dark environment kept at 4 ◦ C, chlorophylls can be preserved for up to 8 days in DMF and 30 days in acetone. On the other hand, acetone extracts higher content of chlorophylls. In 80% acetone, DMF and DMSO extracts, the total chlorophylls contents are 4.80, 4.18, and 3.78 mg per gram of epidermis meal, respectively.

Combustion products of 1,3-butadiene are cytotoxic and genotoxic to human bronchial epithelial cells.

Adverse health effects of airborne toxicants, especially small respirable particles and their associated adsorbed chemicals, are of growing concern to health professionals, governmental agencies, and the general public. Areas rich in petrochemical processing facilities (e.g., eastern Texas and southern California) chronically have poor air quality. Atmospheric releases of products of incomplete combustion (e.g., soot) from these facilities are not subject to rigorous regulatory enforcement. Although soot can include respirable particles and carcinogens, the toxicologic and epidemiologic consequences of exposure to environmentally relevant complex soots have not been well investigated. Here we continue our physico-chemical analysis of butadiene soot and report effects of exposure to this soot on putative targets, normal human bronchial epithelial (NHBE) cells. We examined organic extracts of butadiene soot by gas chromatography-mass spectrometry (GC-MS), probe distillation MS, and liquid chromatography (LC)-MS-MS. Hundreds of aromatic hydrocarbons and polycyclic aromatic hydrocarbons with molecular mass as high as 1,000 atomic mass units were detected, including known and suspected human carcinogens (e.g., benzo(a)pyrene). Butadiene soot particles also had strong, solid-state free-radical character in electron spin resonance analysis. Spin-trapping studies indicated that fresh butadiene soot in a buffered aqueous solution containing dimethylsulfoxide (DMSO) oxidized the DMSO, leading to CH(3)* radical formation. Butadiene soot DMSO extract (BSDE)-exposed NHBE cells displayed extranuclear fluorescence within 4 hr of exposure. BSDE was cytotoxic to > 20% of the cells at 72 hr. Morphologic alterations, including cell swelling and membrane blebbing, were apparent within 24 hr of exposure. These alterations are characteristic of oncosis, an ischemia-induced form of cell death. BSDE treatment also produced significant genotoxicity, as indicated by binucleated cell formation. The combination of moderate cytotoxicity and genotoxicity, as occurred here, can be pro-carcinogenic.

Combustion Products of 1,3-Butadiene Are Cytotoxic and Genotoxic to Human Bronchial Epithelial Cells

Adverse health effects of airborne toxicants, especially small respirable particles and their associated adsorbed chemicals, are of growing concern to health professionals, governmental agencies, and the general public. Areas rich in petrochemical processing facilities (e.g., eastern Texas and southern California) chronically have poor air quality. Atmospheric releases of products of incomplete combustion (e.g., soot) from these facilities are not subject to rigorous regulatory enforcement. Although soot can include respirable particles and carcinogens, the toxicologic and epidemiologic consequences of exposure to environmentally relevant complex soots have not been well investigated. Here we continue our physico-chemical analysis of butadiene soot and report effects of exposure to this soot on putative targets, normal human bronchial epithelial (NHBE) cells. We examined organic extracts of butadiene soot by gas chromatography-mass spectrometry (GC-MS), probe distillation MS, and liquid chromatography (LC)-MS-MS. Hundreds of aromatic hydrocarbons and polycyclic aromatic hydrocarbons with molecular mass as high as 1,000 atomic mass units were detected, including known and suspected human carcinogens (e.g., benzo(a)pyrene). Butadiene soot particles also had strong, solid-state free-radical character in electron spin resonance analysis. Spin-trapping studies indicated that fresh butadiene soot in a buffered aqueous solution containing dimethylsulfoxide (DMSO) oxidized the DMSO, leading to CH(3)* radical formation. Butadiene soot DMSO extract (BSDE)-exposed NHBE cells displayed extranuclear fluorescence within 4 hr of exposure. BSDE was cytotoxic to &gt; 20% of the cells at 72 hr. Morphologic alterations, including cell swelling and membrane blebbing, were apparent within 24 hr of exposure. These alterations are characteristic of oncosis, an ischemia-induced form of cell death. BSDE treatment also produced significant genotoxicity, as indicated by binucleated cell formation. The combination of moderate cytotoxicity and genotoxicity, as occurred here, can be pro-carcinogenic.

Evaluating UV-B effects and EDU protection in cucumber leaves using fluorescence images and fluorescence emission spectra

A newly developed laboratory fluorescence imaging system was used to obtain fluorescence images (FImage) of freshly excised cucumber ( Cucumis sativus L.) leaves in spectral bands centered in the blue (F450), green (F550), red (F680), and far-red (F730) spectral regions that resulted from a broad-band (300-400 nm) excitation source centered at 360 nm. Means of relative fluorescence intensities (RFI) from these spectral fluorescence images were compared with spectral fluorescence emission data obtained from excitation wavelengths at 280 nm (280EX, 300-550 nm) and 380 nm (380EX, 400-800 nm) of dimethyl sulfoxide (DMSO) extracts from these leaves. All three fluorescence data types (FImage, 280EX, 380EX) were used to assess ultraviolet-B (UV-B, 280-320 nm) induced physiological changes and the possible use of N-[2-(2-oxo-1-imidazolidinyl) ethyl]-N′-phenylurea (EDU or ethylenediurea) as a chemical protectant against UV-B damage. Plants exhibited well known foliar growth and pigment responses to UV-B exposure (e.g., increased UV-B absorbing compounds and decreased leaf area, chlorophyll a content; and and lower chlorophyll a/b and chlorophyll/carotenoid pigment ratios). Since EDU alone had no effect on foliar variables, there was no evidence that EDU afforded protection against UV-B. Instead, EDU augmented some UV-B effects when provided in conjunction with UV-B irradiation (e.g., reductions in the chlorophyll/carotenoid ratio, total photosynthetic pigments, and chlorophyll b content).Relative fluorescence intensities (RFI) in the longer visible wavelengths (green, red, and far-red) were uncorrelated for comparisons between the FImage and 380EX data sets. However, blue and green RFI were significantly correlated (0.8≫r≫0.6; P ≤0.002) for comparisons between FImage and 280EX data sets. UV-B treatment caused an increase in blue RFI (e.g., F450) in both images and 280EX measurements. One explanation is that the UV-B excitation of both 280EX and FImage stimulates processes that produce excess blue fluorescence. The molecules that produce the excess blue fluorescence in both the 280EX and the Fimage data are different electron transfer agents that operate in parallel. For FImage, the UV excitation penetrates leaf surface layers to stimulate fluorescence from compounds in mesophyll and epidermal tissues (as occurs for the extracts of leaf discs), whereas emissions captured at longer, less energetic wavelengths, were primarily from the epidermal layer. UV-B irradiated leaves showed much greater heteorgeneity of RFI in both the green (F550 FImag ) and the red (F680 FImag ) bands than unirradiated leaves; this was true irrespective of EDU treatment.Although qualitative responses in individual bands differed between FImage and 380EX data, similar results were obtained in the detection of UV-B induced effects when the red/green and blue/far-red fluorescence ratios of these data were compared. The red/green ratio (either F680/F550 FImage or F675/F525 380EX ) was lower for UV-B exposed plants in both images and 380EX data. UV-B exposure also significantly enhanced the blue/far-red ratio of images (F450/F740 FImage ) and the comparable 380EX ratio (F450/F730 380EX ) for the combined UV-B/EDU group. The far-red/red ratios were not useful in separating treatment effects in images or 380EX. Although comparable ratios were not available in 280EX data, the UV/blue ratio (F315/F420 280EX ) was substantially reduced by UV-B exposure and was inversely related to total photosynthetic pigment content. These findings suggest that the red/green ratio (FImage, 380EX) and the UV/blue ratio (280EX) may be as useful as the blue/far-red ratio (380EX) reported previously in detection of UV-B stress. Furthermore, the results support the validity of the imaging technique as a non-destructive diagnostic tool for assessing UV-B stress damage in plants.

The Mutagenic Potential of AH+ and AH26 by Salmonella/Microsome Assay

The aim of this study was to examine the mutagenic potential of canal sealers AH+ and AH26 by Salmonella/microsome assay. The materials were tested immediately after mixing, 1 hr and 1 month later, respectively. The dimethyl sulfoxide extracts of sealers in amounts of 3.0, 1.5, and 0.75 microliters/plate were used. The plated bacterial strains of Salmonella were TA 98 and TA 100. The results showed that AH+ is mutagenic toward strain TA 100 1 hr after mixing. One month after mixing, mutagenic activity was expressed only in TA 98. Paste A showed strong mutagenicity toward TA 100. AH26 was more mutagenic to the TA 100 immediately after mixing, 1 hr later, and 1 month after it was polymerized. Also it was mutagenic toward TA 98 in the polymerized condition. Further examinations should be conducted to establish a definitive conclusion about mutagenic potential for these two endodontic materials.

Antimutagenicity of the Purple Pigment, Hordeumin, from Uncooked Barley Bran-Fermented Broth

The novel purple pigment hordeumin, an anthocyanin-tannin pigment, was produced from barley bran-fermented broth. The mutagenicity or antimutagenicity of hordeumin was investigated according to the Ames method, an indication of the safety of food, using Salmonella typhimurium TA98. Despite the presence of S-9 mix, hordeumin was not mutagenic. On the other hand, hordeumin effectively decreased a reverse mutation from Trp-P-1, Trp-P-2, IQ, and B[a]P. Furthermore, hordeumin also decreased the reverse mutation from dimethyl sulfoxide extracts of grilled beef.