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1.
Jagetia GC  Baliga MS 《Die Nahrung》2002,46(5):332-336
The effect of 5, 10, 20, 40, 60, 80, 100, 120, and 160 mg/kg body weight (b.wt.) of aqueous extract of cystone (an ayurvedic herbal medicine) administered intraperitoneally was studied on the radiation-induced mortality in mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of cystone, consecutively for five days before irradiation, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. The pretreatment of mice with different doses of cystone before exposure to 10 Gy of gamma-radiation resulted in a dose-dependent elevation in the survival up to 40 mg/kg b.wt., where the highest number of survival (55.55%) was observed by 30 days post irradiation, when compared with the 10 Gy irradiated control (6.66%). Thereafter, the number of survivors declined and reached a nadir at 160 mg/kg, where no survivors could be observed. The optimum protection against irradiation was observed for 40 mg/kg cystone, where the highest number of survivors were reported by 30 days post irradiation and it was 8.34-fold greater than that of the irradiated control group.  相似文献   

2.
The effects of various concentrations (5, 10, 20, 30, 40, 50, 60, and 80 mg/kg body weight (b.wt.) of the leaf extracts of Syzygium cumini Linn. and Eugenia cumini (SCE, black plum, Jamun, family Myrtaceae) on the radiation‐induced sickness and mortality in mice exposed to 10 Gy γ‐irradiation were studied. The treatment of mice with different doses of SCE, consecutively for five days before irradation, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the nondrug‐treated irradiated controls. All doses of SCE provied protection against the gastrointestinal death increasing the survival by 66.66% after treatment with 20, 30, and 40 mg/kg SCE versus a 12% survival in the irradiated control group (oil + irradiation). Similarly, SCE provided protection against the radiation‐induced bone marrow death in mice treated with 10–60 mg/kg b.wt. of SCE. However, the best protection was obtained for 30 mg/kg b.wt. SCE, where the number of survivors after 30 days post‐irradiation was highest (41.66%) when compared with the other doses of SCE.  相似文献   

3.
Jagetia GC  Baliga MS 《Die Nahrung》2003,47(3):181-185
The effects of various concentrations (5, 10, 20, 30, 40, 50, 60, and 80 mg/kg body weight (b.wt.) of the leaf extracts of Syzygium cumini Linn. and Eugenia cumini (SCE, black plum, Jamun, family Myrtaceae) on the radiation-induced sickness and mortality in mice exposed to 10 Gy gamma-irradiation were studied. The treatment of mice with different doses of SCE, consecutively for five days before irradation, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the nondrug-treated irradiated controls. All doses of SCE provied protection against the gastrointestinal death increasing the survival by 66.66% after treatment with 20, 30, and 40 mg/kg SCE versus a 12% survival in the irradiated control group (oil + irradiation). Similarly, SCE provided protection against the radiation-induced bone marrow death in mice treated with 10-60 mg/kg b.wt. of SCE. However, the best protection was obtained for 30 mg/kg b.wt. SCE, where the number of, survivors after 30 days post-irradiation was highest (41.66%) when compared with the other doses of SCE.  相似文献   

4.
The combined effect of γ‐irradiation and refrigeration on the shelf‐life of vacuum‐packaged sea bream (Sparus aurata) fillets was studied by monitoring the microbiological, chemical and sensory changes of non‐irradiated and irradiated fish samples using low‐dose irradiation doses of 1 and 3 kGy. Fish species such as sea bream and sea bass are very popular in the Mediterranean countries due to their high quality characteristics, and their preservation is a constant challenge given their extreme perishability. Irradiation (3 kGy) dramatically reduced populations of bacteria, namely, total viable counts (3 vs 7 log cfu g?1) for the non‐irradiated samples, Pseudomonas spp (<2 vs 7.6 log cfu g?1), H2S‐producing bacteria typical of Shewanella putrefaciens (<2 vs 5.9 log cfu g?1), Enterobacteriaceae (<2 vs 6.0 log cfu g?1) and lactic acid bacteria (<2 vs 3.5 log cfu g?1) after 10 days of storage. The effect was more pronounced at the higher dose (3 kGy). Lactic acid bacteria, Enterobacteriaceae and H2S‐producing bacteria typical of Shewanella putrefaciens showed higher sensitivity to γ‐radiation than did the rest of the microbial species. Of the chemical indicators of spoilage, Trimethylamine (TMA) values of non‐irradiated sea bream increased very slowly, whereas for irradiated samples significantly lower values were obtained reaching a final value of 7.9 and 6.3 mg N per 100 g muscle at 1 and 3 kGy respectively (day 42). Total volatile basic nitrogen (TVB‐N) values increased slowly attaining a value of 67.3 mg N per 100 g for non‐irradiated sea bream during refrigerated storage, whereas for irradiated fish, lower values of 52.8 and 43.1 mg N per 100 g muscle were recorded (day 42). Thiobarbituric acid (TBA) values for irradiated sea bream samples were higher than respective non‐irradiated fish and increased slowly until day 21 of storage, reaching final values of 1.1 (non‐irradiated), 2.0 (1 kGy) and 2.2 mg malonaldehyde kg?1 muscle (3 kGy), respectively (day 42). Sensory evaluation showed a good correlation with bacterial populations. On the basis of overall acceptability scores (sensory evaluation) a shelf‐life of 28 days (3 kGy) was obtained for vacuum‐packaged sea bream, compared with a shelf‐life of 9–10 days for the non‐irradiated sample. Copyright © 2004 Society of Chemical Industry  相似文献   

5.
Mungbeans (Vigna radiata), control and γ‐irradiated at insect disinfestation dose levels (0.25 and 0.75 kGy) were germinated (0–6 days) and the qualitative and quantitative changes in soluble carbohydrates were studied in detail. The key flatulence‐producing raffinose family oligosaccharides in mungbeans were degraded in the irradiated samples at the onset of the germination (0–2 days) compared to the control where it occurred much later (>4 days). However, the reducing sugars, mainly glucose, fructose and galactose, which are metabolised easily, were enhanced in the irradiated samples. At low dose (0.25 kGy), irradiation had no effect on germination and sprout length, indicating that irradiated beans are suitable for use as sprouted beans. These observations clearly indicate that γ‐irradiation at insect disinfestation dose levels improved the digestibility and nutritional quality of mung beans by reducing the content of oligosaccharides responsible for intestinal gas production. © 1999 Society of Chemical Industry  相似文献   

6.
Physico‐chemical (pasting) properties of non‐irradiated (fresh) and γ‐irradiated yam cultivars and sweet potato were determined using Rapid Visco Analyser (RVA). Generally, pasting characteristics of the commodities decreased significantly with increased γ‐irradiation dose. Non‐irradiated sweet potato showed significantly higher peak (45.79), trough (35.25), breakdown (10.54), final (75.21) and setback (39.96) viscosities (in RVU) than γ‐irradiated samples. Also, peak time (6.97 min) and pasting temperature (50.18 RVU) significantly reduced with increased γ‐irradiation dose of tubers. The pasting properties of non‐irradiated and γ‐irradiated sweet potato showed similar but clearer trend compared with yam flours. Also, non‐irradiated and γ‐irradiated Dioscorea rotundata and Dioscorea alata showed significantly higher values of each of the pasting characteristics than values noted in sweet potato. Aside from the TDr 03/00196, peak time did not vary significantly with γ‐irradiation dose.  相似文献   

7.
Grains of the Polish winter wheat variety Begra were subject to γ‐radiation (60Co) within the dose range of 0.05–10 kGy and microwave treatment from 15 to 180 s, the latter resulting in a bulk grain temperature ranging from 28 to 98°C. Both processes were responsible for marked structural changes of wheat kernel endosperm and were pronounced with increasing dose of ionizing radiation or with prolonged time of microwave treatment. Endosperm microstructures of wheat kernels treated with γ‐radiation ranging from 0.05 to 0.5 kGy did not differ from that of untreated ones. Only some changes in the structure of starch granules and proteins were observed at doses of 1, 5 and 10 kGy. Simultaneously at the doses of 5 and 10 kGy a statistically significant decrease of falling number, sodium dodecyl sulfate (SDS) sedimentation values, dough stability and energy were observed, while dough weakening progressed. Microwave treatment longer than 90 s caused marked changes in kernel endosperm structure. Some changes of proteins caused by denaturation created visible fibrils as well as high swelling and deformation of starch granules. This was followed by an increase in the falling number value, decrease in the estimated results of SDS sedimentation test, lowering of the percent of gluten washed out and of the dough energy, respectively. Also a significant decrease in bread quality expressed by volume and score was observed with increasing time of exposure to microwave.  相似文献   

8.
The effects of γ‐irradiation treatments (2.5, 5 and 10 kGy) and microwaves generated from an oven at low and defrost power settings for 0.5, 1 and 2 min on the total proteins and protein patterns of beef liver immediately after treatment and during frozen storage (?18 °C) for different periods were studied. Chemical analyses indicated that the protein content of beef liver was reduced after exposure to γ‐radiation or microwaves and also during frozen storage. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) was used to illustrate the changes in protein bands of different molecular weights and their percentages before and after exposure to gamma and microwave radiation. The main effect of γ‐radiation on the protein patterns of beef liver was the disappearance of some high‐molecular‐weight protein bands and the development of other bands characterised by moderate and low molecular weights. This finding indicates the degradation of beef liver proteins by γ‐irradiation. In contrast, microwave treatment caused an increase in the levels of high‐molecular‐weight protein bands with a concomitant decrease in low‐molecular‐weight protein bands. This phenomenon demonstrates the polymerisation of low‐molecular‐weight proteins under the influence of microwaves. © 2001 Society of Chemical Industry  相似文献   

9.
Three plantain cultivars, Agbagba, Obino L'ewai and Cardaba, harvested at two stages of maturity, were irradiated at 0.1–1.0 kGy prior to storage under tropical ambient conditions. Post‐irradiation storage behaviour showed that plantain fruits at full three‐quarter grade were more responsive to irradiation treatment than at full grade maturity, while Cardaba, a type of cooking banana, showed the least response. Irrespective of varietal differences, irradiation to 0.5 kGy or higher caused severe tissue damage, softening and skin discolouration; however, γ‐irradiation at optimum dose range of 0.15–0.30 kGy effectively delayed ripening for 10–12 days in Agbagba and Obino L'ewai, respectively, without affecting respiratory pattern or fruit quality. © 1999 Society of Chemical Industry  相似文献   

10.
The effect of γ‐irradiation and maize lipids on aflatoxin B1 production by Aspergillus flavus artificially inoculated into sterilized maize at reduced water activity (aw 0.84) was investigated. By increasing the irradiation doses the total viable population of A. flavus decreased and the fungus was completely inhibited at 3.0 kGy. The amounts of aflatoxin B1 were enhanced at irradiation dose levels 1.0 and 1.5 kGy in both full‐fat maize (FM) and defatted maize (DM) media and no aflatoxin B1 production at 3.0 kGy γ‐irradiation over 45 days of storage was observed. The level in free lipids of FM decreased gradually, whereas free fatty acid values and fungal lipase activity increased markedly by increasing the storage periods. The free fatty acid values decreased by increasing the irradiation dose levels and there was a significant enhancement of fungal lipase activity at doses of 1.0 and 1.50 kGy. The ability of A. flavus to grow at aw 0.84 and produce aflatoxin B1 is related to the lipid composition of maize. The enhancement of aflatoxin B1 at low doses was correlated to the enhancement of fungal lipase activity.  相似文献   

11.
Cytogenetic damage expressed as micronuclei (MN) in 4-8-cell embryos generated after irradiation of male or male and female mice in the absence and presence of vitamin C was investigated. Male NMRI mice were whole body exposed to 4 Gy gamma-rays and mated with non-irradiated superovulated female mice in 6 successive weeks after irradiation in a weekly interval. In experiments involving irradiation of both male and female mice, irradiated male mice for 6 weeks post irradiation were mated with female mice irradiated after induction of superovulation. Effect of 100 mg/kg vitamin C (ascorbic acid) on the frequency of MN was also studied. Pregnant animals were euthanized and embryos flushed from the oviducts and fixed on slides. The rate of MN observed in embryos generated from irradiated male compared with control group dramatically increased (P<0.01). Frequency of MN in this group decreased dramatically after vitamin C treatment (P<0.01). Frequency of MN in embryos generated by mating both male and female irradiated mice was higher than that observed for those embryos generated by irradiated male mice alone. However, a considerable modifying effect of vitamin C was observed for this group too (P<0.05). Results indicate that irradiation of gonads during spermatogenesis and preovulatory stage oocytes may lead to unstable chromosomal aberrations and probably stable chromosomal abnormalities affecting pairing and disjunction of chromosomes in successive preimplantation embryos expressed as MN. The way vitamin C reduces clastogenic effects of radiation on germ cells leading to reduced frequency of MN in pre-embryos might be due to its antioxidation and radical scavenging properties.  相似文献   

12.
Whole unprocessed almonds, cashew nuts and walnuts were each subjected to γ‐irradiation (1, 5, 10 and 25 kGy) followed by heat processing including autoclaving (121 °C, 15 psi for 15 and 30 min), dry roasting (138 and 160 °C for 30 min each, 168 and 177 °C for 12 min each), blanching (100 °C for 5 and 10 min), oil roasting (191 °C, 1 min) and microwave heating (500 W for 1 and 3 min). Rabbit polyclonal antibodies were raised against each major protein isolated from defatted, but not subjected to γ‐irradiation and/or any thermal processing, almond, cashew nut and walnut flours. Immunoreactivity of almond, cashew nut and walnut proteins soluble in borate saline buffer, normalised to 1 mg protein ml?1 for all samples, was determined by inhibition enzyme‐linked immunosorbent assay (ELISA) and Western blotting. ELISAs and Western blotting experiments indicated that almond, cashew nut and walnut proteins exposed to γ‐irradiation alone or followed by various thermal treatments remained antigenically stable. Copyright © 2004 Society of Chemical Industry  相似文献   

13.
This study aimed at using essential oil (EO) alone or combined EO with nisin and γ‐irradiation to control Salmonella Typhimurium during the refrigerated storage of mini‐carrots. Peeled mini‐carrots were inoculated with S. Typhimurium at a final concentration of approximately 7 log CFU/g. Inoculated samples were coated by 5 different coating solutions: (i) nisin solution at final concentration of 103 IU/mL; (ii) mountain savory EO solution at 0.35%; (iii) carvacrol solution at 0.35%; (iv) mountain savory EO at 0.35% plus nisin solution of 103 IU/mL; or (v) carvacrol at 0.35% plus nisin solution of 103 IU/mL. Coated mini‐carrots were then irradiated at 0.5 or 1.0 kGy and compared to an unirradiated control sample. Samples were kept at 4 °C and microbial analyses were conducted at days 1, 3, 6, and 9. The results showed that mini‐carrots coated by carvacrol plus nisin solution or mountain savory EO plus nisin solution in combination with irradiation at 1.0 kGy completely eliminated S. Typhimurium to under the detection limit during the storage. Thus, the combined treatments using carvacrol plus nisin or mountain savory EO plus nisin coating solution and irradiation at 1.0 kGy could be used as an effective method for controlling S. Typhimurium in mini‐carrots.  相似文献   

14.
Physical, functional and pasting properties of six maize (Zea mays) cultivars as modified by an increase in γ‐irradiation doses were investigated. From the L*, a* and b* measured, deltachroma, colour intensity and hue angle were calculated. Functional and physicochemical properties of maize flours were determined using standard methods and Rapid Visco Analyser, respectively. Often, the effect of γ‐irradiation on L*, a* and b* values within each cultivar was almost never significant but pronounced between the yellow and white cultivars. Generally, deltachroma, colour intensity and hue angle decreased with increased γ‐irradiation dose. Mean seed bulk density and 100 kernel weight varied from 0.73–0.77 g cm?3 and 23.13–35.42 g, respectively. Loose and packed bulk densities, and water (WAC) and oil absorption capacities of the maize flours were not significantly affected by γ‐irradiation. WAC of nonirradiated and γ‐irradiated maize flours ranged from 1.54–1.62 and 1.09–1.70 g g?1, respectively. Peak, trough, breakdown, final and setback viscosities decreased significantly (P < 0.05) with increased γ‐irradiation dose.  相似文献   

15.
The effects of γ‐irradiation on the biophysical and morphological properties of corn plants were investigated. The irradiation doses were 0, 1, 1.5, 2.5, 5, and 10 krad. Corn grains exposed to 1.5 and 2.5 krad showed highly significant changes in all growth parameters. Fluorescence and light absorption spectra of chlorophyll attributed to different doses treatments of corn grains clearly confirmed the superiority of 1.5 krad irradiation dose in stimulating corn plants. Furthermore, the frequency dependence of the relative permittivity and the electric conductivity of the treated samples have been performed and discussed. The obtained results give another support via the biophysical properties for the 1.5 krad irradiation dose to be the most favorable one to improve the plant growth characteristics.  相似文献   

16.
17.
Grains of the Polish winter wheat variety Begra were subjected to γ‐radiation (grain harvested in 1996) within the dose range of 0.05–10 kGy and microwave heating (grain harvested in 1997) from 28°C to 98°C. Later the grains were divided into two parts, the first was used for direct analyses after treatment. The second part was sown on the experimental fields. The obtained crop was described as the first generation and divided into two parts. One part was destined to determination of starch properties and the second part was sown in order to obtain the second generation crop. The same pattern was conducted in order to achieve the third generation crop. γ‐Irradiation directly applied on the wheat grain reduced statistically significant falling number values and gelatinisation enthalpy (ΔH) of the grain treated by 5 and 10 kGy. Calculated linear regression correlation coefficient between the falling number values and the gelatinisation enthalpy was equal to 0.94 (p ? 0.001) and showed that these two starch characteristics are well correlated in the case of directly irradiated wheat grain. The falling number values, peak temperatures (Tp) and gelatinisation enthalpy (ΔH), in three generations of wheat grain crop studied, did not show any statistically significant differences as a result of indirect effect of γ‐irradiation. Microwave direct heating of wheat grain to 98°C caused a statistically significant increase in the falling number value and decrease in starch gelatinisation power expressed by the enthalpy of gelatinisation (ΔH). The statistically significant changes in the falling number values, slight changes in the peak temperatures (Tp) and enthalpy of gelatinisation (ΔH) were found in all three generation crops as an indirect effect of microwave heating.  相似文献   

18.
Experimental work was carried out in order to determine the usefulness of the 2‐alkylcyclobutanones as markers for irradiated Camembert cheese, salmon meat, mango and papaya. Both 2‐dodecylcyclobutanone (2‐DCB) and 2‐tetradecylcyclobutanone (2‐TCB) were readily detected in Camembert cheese even after storage for 26 days at 10 °C. A linear relationship was observed between irradiation dose (0.5–5 kGy) and the amount of cyclobutanone produced in the cheese. 2‐DCB and 2‐TCB were both identified in salmon meat irradiated in either the chilled (4 °C) or frozen state (−40 °C), although it was noted that less 2‐DCB was measured in the frozen samples. A linear response to increasing irradiation dose was demonstrated for salmon over the experimental range of 1–10 kGy. 2‐TCB was identified as the main marker for irradiated mango and could be detected in samples following storage for 14 days at 10 °C at doses as low as 0.1 kGy. As for the other products investigated, the concentration of this cyclobutanone increased linearly with increasing dose (0.1–2 kGy). With regard to papaya, 2‐DCB was identified as the principal irradiation marker. However, the concentration of this cyclobutanone decreased significantly with time, so that by day 21 of storage at 10 °C it could only be detected at the 2 kGy dose level. 2‐Tetradecenylcyclobutanone (2‐TDCB) was also detected in irradiated mango and papaya. © 2000 Society of Chemical Industry  相似文献   

19.
This study focussed at evaluating the effect of gamma irradiation on the in vitro digestibility, molecular structure and physico‐chemical properties of poovan banana (Musa AAB) starch using γ‐rays from a 60Co source at different doses with a dose rate of 2 kGy h?1. Physico‐chemical properties varied significantly and exhibited strong dose‐dependent relationship. Escalating irradiation leads to decrease in amylose content, pH, swelling power of the starch granules and syneresis of the gelatinised starch, while the same led to an increase in carboxyl content, in vitro digestibility, solubility and water absorption capacity of the starch granules. The results revealed that peak, hold, final and setback viscosities were significantly reduced. X‐ray diffraction pattern remained the same upon irradiation but a decrease in relative crystallinity was observed with increasing irradiation dose. Gelatinisation temperature and enthalpy decreased significantly when the increasing the dose of gamma irradiation.  相似文献   

20.
为创新苏子(Perilla frutescens L.Britt)种质资源及为苏子辐射诱变育种提供技术参考,研究不同剂量60^Co伽马射线(0、200、400、600和800Gy)照射条件下,兴仁花苏和山甲苏子种子的萌发率、田间出苗率和幼苗高度、活力指数以及MDA含量、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性。结果表明,辐射对苏子种子发芽率影响不明显,但对田间出苗率、幼苗高度、活力指数及相关生理指标都存在极显著影响。在800Gy范围内,随着辐射剂量的增强,田间出苗率先缓慢下降后急剧下降,幼苗植株变矮,活力指标降低;而幼苗MDA含量、SOD活性及POD活力均随剂量的增加而不断上升。兴仁花苏比山甲苏子对辐照更为敏感,其田间出苗率急剧下降时的剂量比后者低,其幼苗的生长和生理指标(MDA含量、SOD活性及POD活性)受辐照影响均比山甲苏子明显,其理论半致死剂量和理论临界剂量也比后者低。10Gy/min剂量率下,兴仁花苏的半致死剂量和临界剂量分别为512.37Gy和570.80Gy,山甲苏子的则分别为679.74Gy和716.79Gy。  相似文献   

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