Thai Journal of Toxicology - วารสารพิษวิทยาไทย
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Item Anti-Oxidative Stress Activities of Silibinin on α-Amanitin In Vitro(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) A. Khunnala; S. Narongchai; S. Butkrachang; D. Leelarungrayub; Paitoon NarongchaiAlpha amanitin (\α-amanitin) is the mainly toxic substance in Amanita mushrooms in Thailand. Toxicity of \α-amanitin is directly on the liver organ leading to body systemic failure. Silibinin is an antioxidant and only one medication that can help reduce the toxicity of \α-amanitin, but its mechanism of action is still unclear. The antioxidant activities of silibinin in scavenging free radicals, i.e. superoxide radical, hydroxyl radical, and H₂O₂ as well as the direct trapping between silibinin and \α-amanitin were evaluated in vitro. The scavenging free radicals of silibinin in this study were demonstrated in XO-HX, Ribose- and H₂O₂-ABT/HRP systems by comparing to the standard antioxidants; gallic acid, N-acetylcysteine (NAC), and quercetin. Anti-toxicity was studied in human blood from Į-amanitin oxidation, then the whole blood glutathione (GSH) and plasma malondialdehyde (MDA) levels were detected with DTNB and TBARs. The results showed that silibinin scavenged superoxide radicals lower than quercetin but higher than gallic acid and NAC. It scavenged hydroxyl radicals better than quercetin, NAC and gallic acid, respectively. However, the scavenging activity on H₂O₂ of silibinin was lowest among the compared antioxidants. Interestingly, silibinin protected the GSH and inhibited MDA production in blood from \α-amanitin oxidation in a dose response manner. The study revealed that silibinin had scavenging activity directly on free radicals, especially superoxide, hydroxyl radicals, and H₂O₂. It also protected the GSH and inhibited MDA production in human blood from \α-amanitin oxidation.Item Anticlastogenic Potentials of Ivy Gourd, Sesbania, Lemon Grass and Chinese Kale in the Mouse(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Piengchai KupradinunA number of vegetables and fruits are known to contain various kinds of chemical possessing chemopreventive potential. Recently, we reported that some Thai vegetables, i.e. ivy gourd leaves (Coccinia grandis (L.) Voigt, Sesbania flowers (Sesbania grandiflora Linn.), lemon grass (Cymbopogon citratus Stapf) and Chinese kale (Brassica alboglabra) contained anti-mutagens against indirect carcinogens/mutagens such as alflatoxin B₁1 (AFB₁) and benz (a) pyrene. The present study aimed at the determination of anti-clastogenic activity of the above vegetables against clastogens/carcinogens i.e. mitomycin C (MMC) and 7, 12-dimethylbenz(a)anthracene (DMBA) using the in vivo mouse erythrocyte micronucleus assay. Mice were fed either with semipurified diet containing various concentrations of ground lyophilized vegetables for 2 weeks prior to administration of MMC and DMBA. Blood samples were collected before and after carcinogens administration and counted for reticulocytes both with micronucleus (micronucleated peripheral reticulocytes, MNRETs) and without micronucleus by using fluorescent microscope. It was found that feeding diets containing 5% and 10 % of ivy gourd leaves significantly decreased the number of MNRETs induced by both MMC and DMBA. Sesbania flowers at 5% and 10% also caused a reduction in the number of MNRETs induced by both MMC and DMBA, however, the difference was significant only at high concentration. On the other hand, lemon grass at 5% and 10% decreased MNRETs induced by both MMC and DMBA. Interestingly however, the effect was statistically significant only at high concentration in DMBA-treated group. Chinese kale at 10% and 20% could not reduce MNRETs. The present study demonstrated that leaves of ivy gourd and flowers of sesbania possessed anticlastogenic activity against both direct and indirect-acting clastogens in the mouse. In addition, lemon grass could inhibit the clastogenicity of only indirect-acting clastogen. While Chinese kale did not inhibit the clastogenicity.Item Antimutagenic Potentials of Hydroalcoholic Herbal Extracts towards UV-Induced Mutation(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Ponnaree Kittiwannachot; Panida Borisut; Pimphaka Wanasawas; Lakkhana Ponpanich; Orathai Rattanasuk; Malyn ChulasiriTwelve antimutagenic herbs reported elsewhere towards chemical mutagens were selected for the study.\ Their used parts which had been dried and ground were extracted with hydroalcohol. These extracts were evaluated for the antimutagenicity towards UVA- and UVB-induced mutation using modified Ames test having Escherichia coli B/r WP2 (trpE65) as the tester strain. Results revealed the hydroalcoholic extracts from damask rose (Rosa damascena Mill) flower, emblic (Phyllanthus emblica Linn) fruit pulp, guava (Psidium guajava Linn) leaf and myrobalan (Terminalia chebula Retz) fruit pulp were rather promising. Their IC₅₀ towards both UVA- and UVB-induced mutation was less than 4 mg/plate. These extracts were then separately incorporated into SPF 8 sunscreen lotion. It was revealed that the damask rose and myrobalan sunscreen lotions were more appreciable than the guava and emblic sunscreen lotions. The IC₅₀ of lotions incorporated with damask rose and myrobalan extracts was 4.3 and 2.3% w/w respectively towards UVA-induced mutation, and was 2.5 and 4.2 9% w/w respectively towards UVB-induced mutation. Whereas the IC₅₀ of lotions incorporated with emblic and guava extracts was more than 7% w/w and was significantly higher than the IC₅₀ shown by the unformulated extracts (p \< 0.05). The sunscreen lotions in the presence and absence of these extracts were eventually evaluated for SPF. All lotions with the extracts showed higher values than the non-herbal one.Item Antimutagenicity against Urethane and In vivo Nitrosated Methylurea of Three Bakeries Fortified with Fruit and Herbal Wines(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) J. Pratoomwun; Kaew KangsadalampaiButter cake, pancake and doughnut fortified with each wine, namely, grape wine, Krachaidum wine, Mamao wine and mangosteen wine were determined for their antimutagenicity against urethane and the in vivo nitrosated methylurea. The three-day old trans-heterozygous (mwh flr⁺/mwh TM3) larvae were transferred from regular medium to an experimental medium (substituted each wine fortified bakery for carbohydrate) for mutagenicity test. The antimutagenicity of each bakery was revealed by transferring three-day old trans-heterozygous larvae to an experimental medium containing urethane (20 mM) or the combination of sodium nitrite (36 mM) and methylurea (10 mM). The round wings from the surviving adult flies were analyzed for the occurrence of mutant spots. The results showed that neither wines nor bakeries fortified with wines were mutagenic. Interestingly, fortification of butter cake, pancake and doughnut with most wines improved the antimutagenicity against urethane of bakeries. The antimutagenicity against in vivo nitrosated methylurea of some fortified butter cakes, pancakes and doughnuts was also observed. We proposed that these fruit and herbal wines fortified bakeries might either inhibit activating enzymes (phase I), induce detoxifying enzymes (phase II) or trap urethane. Surprisingly, the ordinary pancake strongly enhanced the mutagenicity of in vivo nitrosated methylurea, but pancake fortified with grape, mamao and mangosteen wines decreased the enhancing activity of the ordinary bakery. Interestingly, pancake fortified with krachaidum expressed significant antimutagenicity against this mutagen. Thus, some components of pancake could increase the formation of mutagen in the in vivo nitrosation of methylurea and those in fortified pancake might inhibit the formation of mutagen. The result in the present study revealed that doughnut fortified with wine possessed strong antimutagenicity and therefore might be the most suitable bakery for wine fortification in order to obtain a functional food that could counteract the action of mutagens.Item Antimutagenicity against Urethane of Mangosteen, Durian Products and Their Combinations in Somatic Mutation and Recombination Test(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) P. Jitwiriyatham; Kaew KangsadalampaiLyophilized durian meat, lyophilized mangosteen meat, durian chip, durian paste and the combinations (1:1, 1:2 and 2:1) of each durian product and mangosteen were determined for their effect on urethane induced somatic mutation and recombination in Drosophila melanogaster. The three-day old trans-heterozygous (mwh flr+/mwh TM3) larvae were transferred to an experimental medium (substituted each sample for 25, 50, 75 or 100% of corn flour) that had urethane (20 mM). We analyzed for the occurrence of mutant spots of the wings from the surviving flies and found that most samples enhanced the mutagenicity of urethane with different degree. The enhancement of urethane mutagenicity might involve in the phenomenon that the chemical compounds in the samples induced the activity of mixed function oxidases and saturation of enzymatic systems involved in the DNA repair pathways since the amount of each sample incorporated into the fly medium seemed to be very high. The results as such indicated that high consumption of durian and mangosteen should be with caution since it might enhance the mutagenicity of the compounds contaminated in our daily food. However, we surprisingly found that the combination of durian paste and mangosteen (2:1) had the highest antioxidant activity (determined with DPPH scavenging capacity and ferric reducing antioxidant power assays) as well as the content of phenolic compounds (determined with Folin-Ciocalteu reagent) while durian chip contained the least antioxidant and phenolic compounds.Item Antimutagenicity of Some Thai Dishes on Urethane Induced Somatic Mutation and Recombination in Drosophila melanogaster(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Kaew Kangsadalampai; N. PratheepachittiThis study examined the mutagenicity of Thai dishes, namely Thai main dishes (Tom Yam Kung, Kaeng Liang, Kaeng Som Pak Ruam, NamPrik Kapi, Nam Prik Makam, and Yam Tua Pu) and Thai one dish meals (Khaow Yam Pak Tai, Khanomjeen Nam-ngiew and Khaow Man Som Tam). The antimutagenicity of the samples on urethane (URE) induced somatic mutation and recombination in Drosophila melanogaster was also determined. Eighty trans-heterozygous Drosophila melanogaster larvae, aged three-days old, obtained from virgin ORR; flr³ virgin female and mwh male were transferred to a test tube containing each Thai dish mix with regular medium (mutagenicity study) or regular medium containing 36 mM URE (antimutagenicity study) until they became adult flies. The ratios (w/w) of Thai dish and a mixture of regular medium or regular medium containing URE were 1:1, 1:2 and 1:4. The occurrences of mutant spots on the round wing of surviving flies were analyzed. It was found that all Thai dishes were not mutagenic. The antimutagenicity of three kinds of Thai dishes at ratios of 1:1 and 1:2 were 61-94 percent inhibition and at a ratio of 1:4 were about 45-83 percent inhibition. The antimutagenic mechanisms were not clearly elucidated in this study but rather suggested the effects of many antimutagens in the components of each dish. The findings from the present experiment seems to justify the claim that Thai dished are good for health, aside from its superb sensory attributes as produced by mixtures of different ingredients.Item Assessment on Sanitation of Traditional Coconut Sugar Production in Samut Songkhram Province(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Junchaiy Prakobsin; Wenika Benjapong; Narisara Moungsrichan; Weeraya KarnpanitCoconut sugar is a product from the fresh coconut sap. The fresh coconut sap, tapping from the flower stalks of coconut palm’s spadix is boiled to evaporate the water until liquid become very sticky. Most production of coconut sugar is a traditional production which is small scale production, steps and methods relying on the experience or indigenous knowledge. As modernized production, the important aspects of the production process should be held to food safety standards. This study evaluated food safety issues in 30 small scale coconut sugar productions in 3 districts of Samut Songkram province, Thailand. This information would be useful for the control in ensuring food safety. The processes of coconut sugar production were analyzed starting with preparation of coconut sap, chewing and product packaging. The study found that some steps of coconut sugar production were not met food safety requirements in at least four ways. First, the production facilities were found to be in direct proximity to residences or animal pens. They lacked walls to protect against dust particles. Secondly, equipments used in production were inappropriate, such as plastic containers that could not endure heat. Also equipment that comes in contact with food was difficult to clean. Furthermore the mixer used in production was not designed for food production. Maintenance, cleaning and storage of equipment and containers were not sanitary. Clean equipment was stored together with equipment that had not been cleaned. In addition, the coconut sugar production producers exhibited unsanitary behaviors. Most producers directly contacted the heated coconut sugar with their unwashed hands. Finally, storage of the product prior to distribution was inadequate in some ways, such as lack of containment and placing product on the ground. The inadequate sanitation need to be corrected for good food sanitation resulting in food safety in coconut sugar products.Item Butylated Hydroxytoluene in Edible Vegetable Oils from Local Markets of Chiang Mai and Mae Hong Son and Its Thermal Stability in Different Cooking Conditions(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Chananat Likhitrungrat; N. Chokethaworn; M. SuttajitButylated hydroxytoluene (BHT) was widely used to protect oxidation and rancidity of food products containing fats and oils since it had high antioxidant activity. In this study, samples of edible vegetable oils from 25 local markets in Chiang Mai province and Mae Hong Son province were determined for BHT contents by gas chromatography-mass spectrometry (GC-MS). Of 18 vegetable oil samples, 3 palm oil samples from the local markets contained BHT in the range of 6.8-86.1 μg/g. The extracts of edible vegetable oil samples had 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in the range of 7.5 to 75.8% which had gallic acid equivalent and BHT equivalent concentrations in the ranges of 6.5 to 65.9 mg/g and 17.2 to173.0 mg/g, respectively. Three different home-cooking conditions were tested for thermal stability of BHT in the samples of palm oil. It was found that cooking temperatures at 98-100°C by boiling or stir-frying for 1-15 min lost BHT 24-31% in the oil, while deep frying at 200±10°C for 5-15 min showed 46-62% loss of BHT.Item Cytoprotective and Cytotoxic Effects of Rice Bran Extracts on H₂O₂- Induced Oxidative Damage in Human Intestinal Caco-2 Cells(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Bunyada Jittorntrum; Rodjana Chunhabundit; Ratchanee Kongkachuichai; Supanart Srisala; Yupin VisetpanitOxidative stress is considered to play a prominent role in the causation of chronic diseases. At present, Rice Science Center, Thailand used plant biotechnology technique to develop new rice strains with increasing nutritive values. Some rice varieties such as Sinlek brown rice and Riceberry pigmented rice showed high levels of antioxidant contents and activities, especially in bran portion. Therefore, the aim of this study was to determine the effects of these bran extracts on H₂O₂-induced oxidative stress in Caco-2 cells. Human intestinal Caco-2 cells were co-incubated with the bran extracts and H₂O₂ for 3 h. Cytotoxic effects of both bran extracts were also evaluated and cell viability measured by MTT assay. Cell growth was inhibited in dose- and time-dependent manner by both bran extracts. The doses at which non-toxic and approximate to IC₅₀ were used to determined effects of the rice bran extracts on H₂O₂ induced oxidative stress. Non-toxic concentrations of both bran extracts protected cells against H₂O₂-induced oxidative stress as antioxidant property. On the other hand, high concentrations enhanced oxidative stress mediated reduction of cell viability. This may result from the pro-oxidant activity that express at high concentrations of the extracts. Sinlek bran extract exhibited antioxidant and pro-oxidant activity higher than Riceberry bran. In addition, the high concentrations of both bran extracts inhibited cell growth in dose and time-dependent manner. Further studies are needed to clarify the potential activities and properties of these bran extract before using as supplement in food or medicine.Item Detection of Urinary Kidney Injury Molecule-1 in a Chronic Cadmium Exposed Population, Mae Sot District, Tak Province(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Amnart Panyamoon; Kowit Nambunmee; Muneko Nishijo; Witaya Swaddiwudhipong; Werawan RungyutthikarnCadmium (Cd) has been found as an environmental pollutant in Mae Sot district, Tak province. Contaminated Cd in water and rice causes high risk of renal dysfunction among the inhabitants. In order to investigate the effect of Cd induced renal dysfunction, a kidney injury molecule-1 (KIM-1), a recently discovered biomarker for an early detection of renal tubular dysfunction, was measured using an enzyme linked immunosorbent assay (ELISA). Polyclonal goat anti-KIM-1, horseradish peroxidase labeled streptavidin and its specific substrate were used in the in-house ELISA technique. The method was validated and used to quantitate KIM-1 in the urine of 700 Mae Sot inhabitants in comparison to two conventional renal biomarkers; N-acetyl-β-D-glucosaminidase (NAG) and β2-microglobulin (β2 -MG). The results showed that KIM-1 standard concentrations provided good linearity (r=0.998) with limit of detection and quantitation at the concentrations of 33.20 pg/ml and 110.68 pg/ml, respectively. The coefficient variation (CV) for inter-day and intra-day precisions for 3 levels of KIM-1 (200, 800 and 3,000 pg/ml) were at 0.8, 1.2, and 2.1% CV and 0.7, 2.4, and 6.7% CV, respectively. The accuracy of the assay was found with 89-101% recovery. The average ± SD of the KIM-1 concentrations in urine samples of 700 Mae Sot inhabitants were at 1,347±1,290 pg/gCr, ranged between 61-15,330 pg/gCr. Using Spearman’s rho analysis, a strong positive correlation between KIM-1 and Cd concentrations (r=0.234, P \< 0.001) was found. The Cd was also correlated well with the NAG (r=0.263, P \< 0.001) and β2-MG (r=0.179, P \< 0.001). Prevalence of high excretion of renal biomarkers was shown in dose response relationship to Cd concentrations. This finding demonstrated that KIM-1 was a sensitive biomarker for detection of renal dysfunction in population with high Cd exposure.Item Different Antimutagenicity against Urethane between Conventionally and Organically Grown Cruciferous Vegetables (Brassica spp.)(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) P. Sakunasing; Kaew KangsadalampaiWe lyophilized conventionally and organically grown Brassica vegetables (white cabbage, red cabbage, Chinese kale, Chinese mustard and cauliflower) and determined for their antimutagenicity against urethane in Drosophila melanogaster. We transferred three-day old trans-heterozygous (mwh flr+/mwh TM3) larvae from regular medium to experimental medium that had 20 mM urethane as the co-administration study. In the pre-feeding studies, we mated the parental flies on the experimental medium to obtain three-day old larvae that were subsequently raised on the regular medium containing urethane as the type 1 study or the experimental medium containing urethane as the type 2 study. The mutant spots of the wings from the surviving flies were analyzed. In the co-administration study, the antimutagenicity of conventional Chinese kale, Chinese mustard and cauliflower was higher than that of the organic ones while organic white cabbage had higher antimutagenicity than that of conventional one. In the pre-feeding studies, most samples (except organic cauliflower) exhibited their antimutagenicity. The antimutagenicity of the samples might be due to induction the phase 2 detoxifying enzyme system of Drosophila by isothiocyanates commonly found in Brassica vegetables. Since most organically grown vegetables are vulnerable to insect infestation that initialize the hydrolysis of their glucosinolates to be unstable isothiocyanates; therefore, the antimutagenicity of organic Chinese kale, Chinese mustard and cauliflower was lower than that of conventional ones. We also found no difference among red cabbages. Surprisingly, the antioxidant activity (DPPH scavenging capacity and ferric reducing antioxidant power) and amount of phenolic compounds (determined using the Folin-Ciocalteu reagent) of all organic vegetables were higher than that of the conventional ones.Item Distribution of Cadmium in Soil around Zinc Mining Area(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) U. Unhalekhaka; C. KositanontCadmium distribution was studied in four creeks of Mae Sot district, Tak province. Huai Mae Tao, a reputed creek, was shown to have low cadmium level at the upstream (8.45 mg/kg soil) and increased to 22.5 mg/kg soil at Ban Mae Tao Mai. Huai Mae Ku, the creek on the other side of the mountain with zinc mining, also showed high cadmium levels (7.55-34.95 mg/kg soil). Huai Mae Tao Ngae Sai, a creek in the north-eastern highland of the zinc mining, which was supposed to have no relation to zinc mining area showed cadmium level of 3.05 mg/kg soil. Huai Nong Khiao, a creek of the south-western highland showed cadmium level of only 1.1 mg/kg soil. From the data, it is suggested that cadmium source is at the upstream of Huai Mae Tao then causing the cadmium accumulation downstream. The cadmium source is unclear. Cadmium levels in the creek of two highlands were similar to the EU Maximum Permissible (MP) level of 3.0 mg/kg soil.Item DNA Extraction from Buccal Cells for Determination of Nucleotide Polymorphism at rs 1800497 Position in Dopamine D2 Receptor Gene(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Pitsinee Inthi; Manit Srisuraphanont; Surinporn Likhitsatien; Lertlakana Bhoopat; Tanin BhoopatSubstance use disorder is influenced by complex genetic and environmental factors. Many studies found that genetics may play an important role in the development of alcohol dependence. Twin and family history studies revealed that genetics affect a heritability of alcoholism approximately 50-60%. The neurotransmitter in brain especially dopamine may associate with rewarding system that might increase risk in alcohol dependence. The dopamine D2 receptor gene (DRD2) allelic status may influence on development of alcohol dependence due to the change in number of receptor. This study aimed to demonstrate that buccal cells could be used as an alternative source of DNA for PCR-RFLP based method to determine the allelic status of DRD2. The DNA samples were extracted from buccal cells using proteinase K and 5% chelex solution, then amplified by PCR method with some modification of the primer sequence. The optimization for annealing temperature was performed. Our PCR system using an annealing temperature at 56°C yielded the most specific amplified DNA of approximately 200 ng/μl. The PCR product was digested with TaqI restriction enzyme at 65°C overnight. The digested product was separated in 8.5% polyacrylamide gel elctrophoresis for genotyping.Item Editorial Board(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2011-01-24) Suleesa SuleesaItem Effect of Aqueous Extract from Cleistocalyx nervosum on Oxidative Status in Rat Liver(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) S. Taya; C. Punvittayagul; T. Chewonarin; Rawiwan WongpoomchaiCleistocalyx nervosum var. paniala, Ma-kiang, is a local plant in northern region of Thailand presenting high antioxidant activity in vitro. Our previous study found that 5 g/kg bw of C. nervosum aqueous extract had no acute toxic effect on rat. The present study was designed to determine effect of aqueous extract of C. nervosum on oxidative status in rat liver. Male Wistar rats were divided into 3 groups. Rats in group 1 were received water as a vehicle control, while group 2 and 3 were received 100 and 500 mg/kg bw of aqueous extract via intragastrium 5 times a week for 4 weeks. At the indicated time, the effect of C. nervosum on oxidative stress and antioxidant system were evaluated. Aqueous extract of C. nervosum did not affect the level of total glutathione, glutathione peroxidase and catalase activities. Low dose of C. nervosum (100 mg/kg bw) significantly increased malondialdehyde formation but high dose (500 mg/kg bw) did not. However, 500 mg/kg bw of C. nervosum extract significantly enhanced heme oxygenase-1 activity. Although the aqueous extract of C. nervosum at low dose exhibited the pro-oxidant effect but at high dose, it reduced oxidative stress in rat liver. In conclusion, the aqueous extract of C. nervosum might show biphasic effect on oxidative status of rat liver.Item Effect of Preparation and Temperature Treatments on Antimutagenicity against Urethane in Drosophila melanogaster and Antioxidant Activity of Three Allium Members(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) A. Aunanan; Kaew KangsadalampaiWe investigated whether the effects of preparations (pounding or chopping) and heat treatments (100\°C or 200\°C) modified the antimutagenicity of garlic, shallot and onion against urethane induced somatic mutation and recombination in\ Drosophila melanogaster. Three-day old trans-heterozygous larvae (mwh flr⁺/mwh TM3) were transferred to an experimental medium (containing a treated sample) that had 20 mM urethane. The wings of surviving flies were analyzed for occurrence of mutant spots. The results showed that all treated samples still had both antimutagenicity and antioxidant activity (determined using DPPH scavenging capacity and ferric reducing antioxidant power) and phenolic compounds (determined using Folin-Ciocalteu reagent). Treating garlic with 100\°C and 200\°C before preparations slightly reduced its antimutagenicity. It was proposed that heat treatment slightly destroyed alliinase; thus, the formation of allicins and other organosulfur compounds (commonly turn to be alkylsulfides or allicin derivatives which are the inducers of phase 2 detoxification system) from alliin was reduced. On the other\ hand, pounding and chopping before applying heat treatments reduced the antimutagenicity of shallot and onion while heat\ treatment had lower effect if the samples still be a bulb or cut into large piece. It was proposed that the formation of sulfur containing compounds derived from isoalliin by alliinase during pounding and chopping were very labile to atmosphere during the 10 min standing at room temperature. Thus the effect of preparation and heat treatment unequally influenced on the antimutagenicity and the antioxidant activity including total phenolic compounds of three Allium members.Item Effects of Bran Extracts from Thai Molecular Breeding Rices on Growth and Apoptosis in Human Promyelocytic Leukemia Cells(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Supanart Srisala; Rodjana Chunhabundit; Ratchanee Kongkachuichai; Bunyada Jittorntrum; Yupin VisetpanitRice bran, the outer layer of brown rice, contains biologically active compounds which mediate chemo-preventive properties. Thus, in the present study, we evaluated the anti-carcinogenic effects of bran extracts from non-pigmented (Sinlek) and pigmented (Riceberry) rices on human promyelocytic leukemia cell line (HL-60 cells). The results showed that the treatment with rice bran extracts for 24 and 72 hours reduced cell viability in a dose- and time-dependent manner. Riceberry rice bran extract showed higher cytotoxic activity, corresponding with the lower IC₅₀ compared to Sinlek variety. The low concentrations of both rice bran extracts which did not affect cell viability were able to inhibit DNA synthesis, whereas the higher selected concentrations that reduced viable cells could induced apoptosis. The apoptotic events were confirmed by chromatin condensation and nuclear fragmentation in cells after AO/EB nuclear staining as well as dose- and time- dependent increase of caspase activity. The findings suggested that bran extracts of new Thai rice varieties exhibited growth inhibitory effects on the human leukemia cells through cytostatic and cytotoxic mechanism. The results also indicated that killing leukemia cells by rice bran extracts partially involved activation of caspases and induction of apoptosis.Item Effects of Curcumin on Cadmium-Induced Hepatotoxicity in Rats(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2010-03-18) Naovarat Tarasub; K. Narula; W. Devakul Na AyutthayaCadmium (Cd), an environmental contaminant, undergoes redox cycling with generation of free radicals inside the biological system. Curcumin, the yellow bioactive component of turmeric has established its antioxidant activities. The present study evaluates possible ameliorating effects of curcumin on Cd acetate induced hepatotoxicity in adult male Wistar rats. The animals were treated once daily by oral gavage for five days and divided into four groups: control, Cd acetate 200 mg/kg BW, curcumin 250 mg/kg BW and pretreatment with curcumin 250 mg/kg BW for one hour before administration with Cd acetate 200 mg/kg BW. After 24 h of the last treatment, the animals were killed to determine the activities of hepatic marker enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, the level of malondialdehyde (MDA), reduced glutathione (GSH) in liver homogenate and histological changes of liver tissues by light microscope. The results showed that Cd treatment caused a significant increase of serum AST (p \< 0.001) and ALT (p \< 0.05), the increased hepatic level of MDA (p \< 0.01), the decreased hepatic level of reduced GSH (p \< 0.05) when compared to the control group. In addition, histological examination revealed that Cd treatment also caused hydropic swelling of hepatocyte with vacuolated cytoplasm. This study could provide a possible explanation to hepatotoxicity resulting from exposure to Cd in the environment. In addition, the pretreatment with curcumin before Cd administration could not inhibit the changes against Cd toxicity. Therefore, it was concluded that curcumin at dose of 250 mg/kg BW could not prevent the toxic effects of Cd against oxidative damages in rat liver since no improvement of all parameters by curcumin treatment.Item Efficiency of some commercial herb extracts and fresh herb extracts on inhibition of Staphylococcus aureus growth(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2011-01-24) Subuntith NimratThe antibacterial activity of two commercial herb extracts (Curcuma (Curcuma longa Linn.)and Garlic (Allium sativum Linn.)) extract on 20 isolates of Methicillin-resistant Staphylococcusaureus (MRSA) and 20 isolates of Methicillin-susceptible Staphylococcus aureus (MSSA) wasstudied and compared with six fresh herb extracts (Curcuma, Garlic, Ginger, Chinese ginger, Chilli,and Citrus leaf) macerated in 99.8% methanol at the proportion of 1:1 (w/v) of the test herb andmethanol. The extracts of each test herb were prepared at three concentrations of 20, 100 and 500mg/ml and then all dilutions were evaluated for efficiency on 20 isolates of MRSA and 20 isolates ofMSSA by disk diffusion method. Result showed that extract from Curcuma exhibited the bacterialactivity against MRSA and MSSA (10% of MRSA 20 isolates and 5% of MSSA 20 isolates,respectively). However, the effect of commercial herb extracts from Garlic and all of fresh herbextracts did not inhibit both test MRSA and MSSA. Therefore, the results suggested that commercialherb extract of Curcuma was able to inhibit some isolates of MRSA and MSSA.Item Electronic waste and hazardous substances(Thai Journal of Toxicology - วารสารพิษวิทยาไทย, 2011-01-24) Suleeporn SangrajangE-waste is defined as computer central processing units, monitors, televisions, cell phones andother digital devices. The rapidly increasing number of e-waste has the potential to create seriousconsequences for human health and environmental quality because hazardous chemicals are used incomponents of electrical and electronic devices that can release into the soil, water supplies, andevaporate into the air when these electronic wastes are placed into landfills or incinerators. Toxic heavymetals most commonly found in e-wastes include lead, mercury, cadmium, chromium, beryllium,antimony and other toxins such as brominated flame retardants, polyvinyl chloride, polychlorinatedbiphenyls, triphenyl phosphate, nonylphenol, and polychlorinated naphthalene. Moreover, dioxins andfurans are released when electronics containing chlorinated plastics or plastic treated with brominatedflame retardants are incinerated. The European Union (EU) has introduced legislation making producersresponsible for their end of life products and banned the use of certain hazardous substances in electricaland electronic products. However these products are being purchased at a rapidly increasing rate. Ewastenow should be the first priority public health issue worldwide.
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