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21.
Dichloromethane extracts of juices from fresh cabbages, including four known (Brutus, Galaxy, Bentley, Structon) and two unknown cultivars, were analyzed by X-MS for the presence of sinigrin degradation products. Allyl isothiocyanate (AITC), which has been reported to be the important aroma compound of freshly disrupted cabbage was not detected in any of the dichloromethane extracts of cabbage juice. Instead, 1-cyano-2,3-epithiopropane, which is one of the isomers of AITC, was the primary volatile compound in all cabbage extracts. AITC was detected in relative trace concentration only when cabbage juice was injected into the GC, using a wide bore, packed column. Thus, the relative importance of AITC and 1-cyano-2,3-epithiopropane to the aroma of freshly disrupted cabbage should be considered.  相似文献   
22.
The use of fluorescent probes as indicator and tracer molecules is becoming an important aspect of plant cell biology. In many cases the dye, whether introduced directly into the cytosol or sequestered by the cell from its external environment, is preferentially transferred to the vacuole. In the light of increasing evidence for endocytosis in plant cells, the sequestration of high-molecular-weight fluorescent dextrans and the membrane-impermeant dye Lucifer Yellow-CH into the vacuole has been cited as evidence supporting the presence of a fluid-phase endocytic pathway. In this review we consider these recent reports of vacuolar sequestration in the light of new evidence arising on the mechanisms underlying dye uptake.  相似文献   
23.
为解决防伪技术中荧光织物制备方法复杂和成本高的问题,采用分散聚合法制备表面带有负电荷的羧基化聚苯乙烯微球(CPS),再以阳离子表面活性剂十八烷基三甲基溴化铵为改性剂,利用静电自组装法吸附荧光染料异硫氰酸荧光素(FITC),制备羧基化聚苯乙烯荧光微球(CPS-FITC),最后将其负载于织物上制备荧光织物。结果表明:所制备的荧光微球和荧光织物在紫外灯(365 nm)下具有明亮的黄绿色荧光,且放置不同时间(1~9 d)、在不同的pH值(3~11)下,经多次摩擦和水洗后均能保持良好的荧光稳定性。该制备方法操作简便、成本低且荧光强度高,可用于不同织物的防伪检测。  相似文献   
24.
Volatile allyl isothiocyanate (AITC) derives from the biodegradation of the glucosinolate sinigrin and has been associated with growth inhibition in several plants, including the model plant Arabidopsis thaliana. However, the underlying cellular mechanisms of this feature remain scarcely investigated in plants. In this study, we present evidence of an AITC-induced inhibition of actin-dependent intracellular transport in A. thaliana. A transgenic line of A. thaliana expressing yellow fluorescent protein (YFP)-tagged actin filaments was used to show attenuation of actin filament movement by AITC. This appeared gradually in a time- and dose-dependent manner and resulted in actin filaments appearing close to static. Further, we employed four transgenic lines with YFP-fusion proteins labeling the Golgi apparatus, endoplasmic reticulum (ER), vacuoles and peroxisomes to demonstrate an AITC-induced inhibition of actin-dependent intracellular transport of or, in these structures, consistent with the decline in actin filament movement. Furthermore, the morphologies of actin filaments, ER and vacuoles appeared aberrant following AITC-exposure. However, AITC-treated seedlings of all transgenic lines tested displayed morphologies and intracellular movements similar to that of the corresponding untreated and control-treated plants, following overnight incubation in an AITC-absent environment, indicating that AITC-induced decline in actin-related movements is a reversible process. These findings provide novel insights into the cellular events in plant cells following exposure to AITC, which may further expose clues to the physiological significance of the glucosinolate-myrosinase system.  相似文献   
25.
This paper describes the results of a study on use of the adsorption–regeneration technique for recovery of dissolved allyl isothiocyanate(AITC) which is present in significant quantities in steam distillation condensate of mustard essential oil (MEO). Equilibrium and dynamic breakthrough studies were carried out. The adsorbents used were polymeric adsorbents: Amberlite XAD‐2, Amberlite XAD‐4, Amberlite XAD‐7, NPA‐1 and NPA‐2. The results obtained indicate that Amberlite XAD‐4 is the best amongst these various adsorbents. AITC recoveries in excess of 95% were obtained, indicating the feasibility of this approach. Further, since no chemical reactions are involved the recovered AITC retains its ‘natural’ origin. © 2000 Society of Chemical Industry  相似文献   
26.
Glucosinolates, found in plants of the genus Brassica, release physiologically active metabolites, such as isothiocyanates and nitriles, in the digestive tract under the action of plant or bacterial myrosinase. Isothiocyanates are excreted in the urine as their mercapturic acid derivatives. To study the influence of diet on isothiocyanate release, two groups of eight rats were offered either a cauliflower-based diet or a standard laboratory rat diet. After 10 days' adaptation to the diets release of allyl isothiocyanate (AITC) from a single oral dose of sinigrin, a glucosinolate commonly occurring in brassicas, was quantified. Each rat was dosed with 50 μmol of either sinigrin or AITC by stomach tube and urine was collected at 0, 2, 6, 24 and 48 h after administration. Three days later, rats which had previously received sinigrin were administered with AITC and vice versa. The concentrations of urinary mercapturic acids of isothiocyanates were determined by HPLC. Recoveries of the mercapturic acid derivative of AITC in each animal were used to estimate AITC production in sinigrin-dosed rats. Estimates of AITC release from sinigrin showed that a greater proportion of administered sinigrin was hydrolysed to AITC in cauliflower-fed rats than in rats fed a control diet (0·412 vs 0·134; P〈0·001). The approach should allow more rigorous investigation of the influence of dietary factors on glucosinolate hydrolysis in vivo. © 1997 SCI.  相似文献   
27.
28.
Phenethyl isothiocyanate (PEITC), a compound derived from cruciferous vegetables, has garnered attention for its anticancer properties. This review synthesizes existing research on PEITC, focusing on its mechanisms of action in combatting cancer. PEITC has been found to be effective against various cancer types, such as breast, prostate, lung, colon, and pancreatic cancers. Its anticancer activities are mediated through several mechanisms, including the induction of apoptosis (programmed cell death), inhibition of cell proliferation, suppression of angiogenesis (formation of new blood vessels that feed tumors), and reduction of metastasis (spread of cancer cells to new areas). PEITC targets crucial cellular signaling pathways involved in cancer progression, notably the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB), Protein Kinase B (Akt), and Mitogen-Activated Protein Kinase (MAPK) pathways. These findings suggest PEITC's potential as a therapeutic agent against cancer. However, further research is necessary to determine the optimal dosage, understand its bioavailability, and assess potential side effects. This will be crucial for developing PEITC-based treatments that are both effective and safe for clinical use in cancer therapy.  相似文献   
29.
BACKGROUND: Escherichia coli O157:H7 can survive commercial manufacture of some uncooked fermented meats. External application of microencapsulated allyl isothiocyanate (AIT) or hot (non‐deheated) yellow mustard powder was used to inactivate the pathogen during dry‐cured Westphalian ham manufacture. RESULTS: Within 45/80 days, E. coli O157:H7 numbers were reduced 5 log10 CFU g?1 by 400 µg kg?1 AIT or 60 g kg?1 mustard powder, but 80 days were required in the untreated control. Mustard powder but not AIT reduced numbers of lactic acid bacteria and staphylococci. Mustard powder or ≥ 300 µg kg?1 AIT inhibited yeasts and moulds but did not affect ham pH or water activity. CONCLUSION: The commercial Westphalian ham process without AIT or mustard powder treatment was validated capable of reducing E. coli O157:H7 5 log10 CFU g?1. Surface treatments with ≥ 300 µg kg?1 microencapsulated AIT or 60 g kg?1 yellow mustard powder reduced the time required for this reduction by 40–50%. AIT volatility from microcapsules or hot mustard powder during application of these compounds may restrict their use in production facilities. Copyright © 2009 Society of Chemical Industry  相似文献   
30.
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