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991.
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993.
Fangyuan Zhao Yajun Wu Lili Guo Xinshi Li Jianxun Han Ying Chen Yiqiang Ge 《European Food Research and Technology》2013,236(5):799-815
So far royal jelly (RJ) has been widely used as a kind of popular and traditional food for health promotion. However, the quality of RJ is vulnerable to improper storage conditions. In order to prohibit the low quality RJ products entering the market and consequently affect the health of humans, it is necessary to define the quality parameters and establish corresponding detection methods for the freshness of RJ. In this research, we applied two-dimensional polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight mass spectrometry to research major royal jelly proteins (MRJPs) changes under different storage conditions after 6-month storage, looking for a stable and reliable protein marker which was also feasible to detect the freshness of RJ. Further research with the help of Western blotting analysis (WB) confirmed that, under room temperature, MRJP5 began to hydrolyze within 30 days and would completely degrade within 75 days, indicating that MRJP5 can be adapted as a freshness marker for RJ products. Moreover, the assessment results of the freshness of 12 commercial RJ products with WB showed that MRJP5 was present in twelve RJ samples at different abundance levels which further confirmed the detection of MRJP5 could be a feasible method to assess the quality and freshness of commercial RJ products. 相似文献
994.
灵菌红素属于天然色素,具有离体抑制肿瘤和癌症细胞增殖、抑制微生物生长以及抗疟疾和免疫抑制等功效,具有潜在的巨大应用价值。缺少急性经口毒性和遗传毒性实验的研究限制了灵菌红素在食品工业领域的应用。本研究依据食品安全国家标准进行了灵菌红素的小鼠急性经口毒性实验、哺乳动物红细胞微核实验、小鼠精子畸形实验和细菌回复突变实验。结果表明,灵菌红素急性经口半数致死剂量LD_(50)10 g/kg(以体质量计),3项遗传毒性实验结果为阴性,灵菌红素对小鼠的急性经口毒性属无毒级,对正常细胞无毒,对动物生殖系统没有毒害。 相似文献
995.
996.
Yixing Wang Liheng Dai Kai Qu Lu Qin Linzhou Zhuang Hu Yang Zhi Xu 《Frontiers of Chemical Science and Engineering》2021,15(4):892-901
Photocatalytic membranes have received increasing attention due to their excellent separation and photodegradation of organic contaminants in wastewater. Herein, we bound Ag-AgBr nanoparticles onto a synthesized polyacrylonitrile-ethanolamine (PAN-ETA) membrane with the aid of a chitosan (CS)-TiO2 layer via vacuum filtration and in-situ partial reduction. The introduction of the CS-TiO2 layer improved surface hydrophilicity and provided attachment sites for the Ag-AgBr nanoparticles. The PAN-ETA/CS-TiO2/Ag-AgBr photocatalytic membranes showed a relatively high water permeation flux (~ 47 L·m–2·h–1·bar–1) and dyes rejection (methyl orange: 88.22%; congo red: 95%; methyl blue: 97.41%; rose bengal: 99.98%). Additionally, the composite membranes exhibited potential long-term stability for dye/salt separation (dye rejection: ~97%; salt rejection: ~6.5%). Moreover, the methylene blue and rhodamine B solutions (20 mL, 10 mg·L−1) were degraded approximately 90.75% and 96.81% in batch mode via the synthesized photocatalytic membranes under visible light irradiation for 30 min. This study provides a feasible method for the combination of polymeric membranes and inorganic catalytic materials. 相似文献
997.
Ye Ding Xiaoqian Dai Yanfei Jiang Zhaofeng Zhang Lei Bao Yujie Li Feng Zhang Xiaotao Ma Xiaxia Cai Lulu Jing Jiaojiao Gu Yong Li 《Molecular nutrition & food research》2013,57(2):365-369
Although ER stress in pancreas, liver, and adipose tissue was reported to be a novel event linked to the pathogenesis of type 2 diabetes mellitus, there is much less information on this event in skeletal muscle. Some studies indicated that treatment with antioxidants had beneficial effects on ER stress and diabetes. This study focuses on the effects of a strong antioxidant, grape seed proanthocyanidin extracts (GSPE), on skeletal muscle in diabetic rats induced with low dose streptozotocin‐ and a high‐carbohydrate/high‐fat diet. After 16 wk of GSPE treatment, diabetic rats showed decreased plasma glucose levels and insulin resistance. The efficacious effect of GSPE was manifested by the amelioration of muscular damage and dysfunction, as observed by histological examination and periodic acid Schiff staining. Concurrently, calcium overload and the abnormal activities of antioxidant enzymes and ATPases in diabetic muscles were partially reversed by GSPE treatment. GSPE also increased the activity of protein kinase B (a mediator of insulin's metabolic action) and partially alleviated severe ER stress. These findings suggest that GSPE may have auxiliary therapeutic potential for type 2 diabetes mellitus by decreasing oxidative stress and ER stress in skeletal muscle. 相似文献
998.
采用PCR-变性梯度凝胶电泳(PCR-DGGE)技术法检测不同酒酿样品中微生物多样性,发现酒酿中包含酿酒酵母属(Saccha-romyces sp.)、毕赤酵母属(Pichia sp.)、乳杆菌属(Lactobacillus sp.)和葡萄糖杆菌属(Gluconobacter sp.)等。从3种酒酿中分离3株优势酵母菌、1株乳酸杆菌和1株球菌,经鉴定为2株酿酒酵母(Saccharomyces cerevisiae)、1株贝酵母(Saccharomyces bayanus)、坚韧肠球菌(Enterococcus durans)和植物乳杆菌(Lactobacillus plantarum)。3株优势酵母菌MJN2、17JN2和MJN3表现了较强的产酒精能力,培养48h后,酒精产量分别达到1.4%vol、1.5%vol和2.2%vol,2株优势乳酸菌JN3和JN1表现出了较强的产酸能力,培养24h后,pH值分别达到5.13和3.69。 相似文献
999.
将 3个品种的烟草 (NicotianatabacumL .)叶片在不同光照强度下处理 ,研究了光强对烟叶光合作用的影响。结果表明 ,随着处理光强的增加 ,烟叶的光系统Ⅰ (PSⅠ )、光系统Ⅱ (PSⅡ )及全电子传递活性和碳酸酐酶 (CA)活性变化呈现先上升后下降趋势 ,6 0 0 μmol·m-2 ·s-1光强下达到最大值。其中PSⅡ电子传递活性及CA活性在 6 0 0 μmol·m-2 ·s-1后下降迅速。RuBP羧化酶 (RuBPCase)初始活性先上升直至光强达到 40 0 μmol·m-2 ·s-1,之后随光强增加而下降 ,RuBP Case总活性则随光强增加变化不大。表明烟叶光合机构及RuBPCase、CA活性下降略早于光饱和点 (6 0 0~ 80 0 μmol·m-2·s-1) ,30 0~ 6 0 0 μmol·m-2 ·s-1为烟叶光合机构运转及酶活性的最适光强 ,强光下 (大于 90 0 μmol·m-2 ·s-1光强 )烟叶发生光抑制。 相似文献
1000.