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141.
Iio K Okada Y Ishikura M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(3):183-189
Single oral dose and 13-week oral subchronic toxicity studies of fucoxanthin-containing oil extracted from microalga, Chaetoseros sp., were conducted in rats. In the single oral dose study, no mortality and no change related to the test material were observed. Thus, the 50% lethal dose of microalgal fucoxanthin oil is more than 2,000 mg/kg body weight. In the 13-week oral dose study, 0, 20 or 200 mg/kg body weight of microalgal fucoxanthin oil was administered. The fucoxanthin-administered groups, showed no mortality and no abnormalities. This result suggested that the no-observed-adverse-effect level of fucoxanthin-containing oil extracted from microalga Chaetoseros sp. was 200 mg/kg body weight under the tested subchronic dose condition. 相似文献
142.
Simultaneous determination of dichlorvos and trichlorfon in agricultural products by GC-FPD 总被引:1,自引:0,他引:1
Yamada N Takahata J Sasaki K Toyoda M Nakamura R Yoshida K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(4):196-201
We studied a gas chromatographic method for the determination of dichlorvos (DDVP) and trichlorfon (DEP) in agricultural products. DDVP and DEP were extracted from agricultural products with acetone and re-extracted with ethyl acetate instead of dichloromethane. DDVP and DEP were eluted in one fraction on a silica gel column using n-hexane-acetone (1:1). DEP is a thermally labile compound, so it was derived to a more thermally stable compound by acylation with N-methylbis(trifluoroacetamide) and pyridine in acetone at 60 degrees C for 2 hours. DDVP and the DEP-TFA derivative were determined simultaneously by GC-FPD. The recoveries of DDVP and DEP from agricultural products spiked at levels of 0.1 microgram/g were 72.6-117.7% and 86.2-106.6%, respectively. The detection limits were 0.03 microgram/g in powdered tea and < or = 0.01 microgram/g in other samples. An interlaboratory study by 6 laboratories was conducted to validate this proposed method for 6 crops. Repeatability ranged from 3.1 to 7.8% for DDVP and from 3.4 to 8.3% for DEP, and reproducibility, from 6.9 to 15.5% for DDVP, and from 7.9 to 21.8% for DEP. Precision values were well within statistically predicted levels. 相似文献
143.
Masaaki Imanaka Shin-Ichi Yamabe Jun Yamamoto Kanae Koezuka Shiho Take Arata Sato Kumiko Sasaki 《Journal of food science》2005,70(9):C529-C533
ABSTRACT: The oxidative degradation of bisphenol A (BPA) by several fruit homogenates was investigated. Their homogenates were incubated with BPA at 25 °C for 0 to 120 min, and the acetone extracts were analyzed by high-performance liquid chromatography (HPLC) with a photodiode array detector (200 to 650 nm). The 2 degradation products (UK-1 and UK-2) from BPA were detected on HPLC chromatograms (280 nm). UK-1 and UK-2 were identified to be 2-(3,4-dihydroxyphenyl)-2-(4-ydroxyphenyl) propane, (3-OH-BPA) and 4-[1-(3,4-dihydroxyphenyl)-isopropyl]benzene-1,2-diol, (3,3'-diOH-BPA), respectively, by HPLC-MassPectrometry (LC-MS). In the process of incubation, the peak of 3-OH-BPA attained the maximum value in the 1st 20 min, and that of 3,3'-diOH-BPA increased more slowly, attaining the maximum in 50 min. On the other hand, incubation of 3-OH-BPA (instead of BPA) with grape homogenates gave the maximum peak of 3,3'-diOH-BPA in only 10 min. 3, 3'-diOH-BPA was a polyphenol compound that contained 4 hydroxyl groups. These results suggested that BPA would be degraded (converted) to brown pigments through the compounds of 3-OH-BPA and 3, 3'-diOH-BPA in some fruit homogenates. 相似文献
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OBJECTIVE: To evaluate the safety and efficacy of stapled anastomosis in left sided colorectal reconstructions. DESIGN: Prospective study. SETTING: District hospital, UK. SUBJECTS: 218 Consecutive patients who underwent elective colorectal reconstructions with stapled anastomoses between July 1980 and July 1994. INTERVENTIONS: 154 Anterior resections of the rectum using single or double stapled anastomoses, 37 rejoining after Hartmann's operations, and 28 restorative proctocolectomies with formation of J pouch ileoanal anastomoses. MAIN OUTCOME MEASURES: Morbidity and mortality. RESULTS: There were 5/154 clinical anastomotic leaks after anterior resection of the rectum and 1/28 after stapled J pouch ileoanal anastomoses. There were no leaks after rejoining of Hartmann's. The overall clinical leak rate was therefore 3%. 11/154 tumours recurred locally after anterior resection of the rectum (7%) during a mean follow up of 18 months, and 8 (73%) developed within 2 years of operation. All but one recurrence developed after single stapled anastomosis. Dukes' staging remains the most reliable prognostic indicator of the local recurrence of the tumour. There were five postoperative deaths after anterior resection but none after Hartmann's procedure or J pouch ileoanal anastomosis, giving an overall postoperative mortality of 2.3%. CONCLUSION: The use of stapling instruments in left sided colorectal anastomosis is safe and technically easy, with a low clinical anastomotic leak rate and an acceptable rate of local recurrence after anterior resection of the rectum. 相似文献
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Plant‐derived 3‐deoxyanthocyanidins are photochromic materials that are coloured under ultraviolet (UV) irradiation and decoloured under light‐shielded storage. In this study, the optimised solvent composition is investigated to enhance the photochromic performance of luteolinidin, a 3‐deoxyanthocyanidin derivative. The visible absorbance ratio between the solution after UV irradiation and after storage in the dark, an index of photochromic performance, was found to be affected by the pH of the solution, and the value reached a maximum when the pH of the solution was 5.7. The type of organic solvent, which is necessary to dissolve luteolinidin, also affected the photochromic performance. When diethylene glycol or dipropylene glycol was used, the value of the absorbance ratio was especially large. Furthermore, this optimised solvent composition displayed excellent photochromic properties with an extract from the sorghum grain shell containing a large amount of 3‐deoxyanthocyanins. 相似文献
150.
Kumiko Keto Toshihiro Araki Tae Kitamura Naoko Morita Mika Moori Yuzuru Suzuki 《Starch - St?rke》1999,51(7):253-258
A thermophilic soil isolate, Bacillus stearothermophilus KP1289, that grew from 41 °C to 69 °C, produced extracellular inulinases in the presence of inulin. One (inulinase II) of these enzymes was purified to homogeneity. The molecular weight (Mr) and the isoelectric point of the enzyme were estimated as 54,000 and 5.0, respectively. The enzyme was active between 30 and 75 °C and at pH 4.5—8.6 with an optimum at 60 °C and pH 6.1. At 69 °C and pH 7.0 the half-life of the enzyme was 10 min. The enzyme released fructose exo-wise from the non-reducing end of inulin (Mr = 4,5000). The Michaelis constant, catalytic center activity, and specificity constant for inulin at 60 °C and pH 5.0 were 80 mM (360 mg/mL), 460 s—1, and 5.8 s—1 mM—1, respectively. The ratio of specificity constants for inulin, sucrose, and raffinose was 1:0.50:0.16. The enzyme was classified as a thermophilic thermostable β-D -fructan fructohydrolase (EC 3.2.1.80). 相似文献