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71.
The aim of this study was to evaluate the antioxidant mechanisms of red ginseng essential oil (REO) in cells as well as in an animal model. REO was prepared by a supercritical CO(2) extraction of waste-products generated after hot water extraction of red ginseng. In HepG2 cells, REO diminished the H(2)O(2)-mediated oxidative stress and also restored both the activity and expression of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Administration of REO inhibited the phosphorylation of upstream mitogen-activated protein kinases (MAPKs) such as c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38. In mice, the CCl(4)-mediated elevation of serum aspartate transaminase and alanine transaminase as well as the induction of hepatic lipid peroxidation were decreased by REO administration. REO treatments also resulted in up-regulation of the antioxidant enzyme expression in the liver. Moreover, increased phosphorylations of MAPKs were inhibited after REO administration. Overall, REO seems to protect the liver from oxidative stress through the activation and induction of antioxidant enzymes via inhibition of MAPKs pathways. 相似文献
72.
以晚熟葡萄品种红地球为试材,探讨了几种不同透光率的果袋对葡萄果实有关性状的影响,结果表明:不透光的复合袋极为显著地降低果实单粒重、总糖含量和糖酸此;透光率为16%的红色袋显著降低果实糖酸比,但对总糖含量、单粒重无显著影响;透光率为60%的无纺布袋对果实品质有一定提高作用;套袋处理的果实钙含量显著低于对照,且随着果袋透光率的降低而降低;透光率高的果袋袋内果实单宁含量偏高;各处理果实Vc含量均无显著差异.葡萄果实对光照强度的需求存在临界值,当袋内光照强度低于外界自然光照的1.4%左右时,果实生长发育开始受到影响. 相似文献
73.
SO4和贝达砧木对鄞红葡萄生长与果实品质的影响 总被引:3,自引:0,他引:3
以SO4和贝达砧木嫁接鄞红葡萄,研究这两种砧木对鄞红葡萄生长和果实品质的影响.结果表明,与自根苗相比,嫁接SO4和贝达砧木的鄞红葡萄萌芽和结实状况良好,果实着色均匀,叶片叶绿素、可溶性固形物、总糖和产量均较自根苗增加,是平原水网地区鄞红葡萄的优良砧木. 相似文献
74.
Coralia Osorio Nelson Hurtado Corinna Dawid Thomas Hofmann Francisco José Heredia-Mira Alicia Lucía Morales 《Food chemistry》2012
The anthocyanin composition of tamarillo (Solanum betaceum Cav., red variety) and Andes berry (Rubus glaucus Benth.) was determined by HPLC–PDA and HPLC–ESIMS. From the anthocyanin-rich extracts (AREs), pure compounds (1–7) were obtained by MLCCC (multilayer countercurrent chromatography) and further preparative HPLC, and their unequivocal structures were obtained by 1D and 2D NMR analyses. The new anthocyanin delphinidin 3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside-3′-O-β-d-glucopyranoside, as well as the known cyanidin-3-O-rutinoside, pelargonidin-3-O-rutinoside, and delphinidin-3-O-rutinoside were identified as constituents of tamarillo fruit. Although the anthocyanin composition of Andes berry had been reported before in the literature, the unequivocal structure elucidation of the major compound, cyanidin-3-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-xylopyranosyl-(1 → 2)-β-d-glucopyranoside, was achieved for the first time. 相似文献
75.
Kashif Ghafoor Sun‐Ok Kim Dong‐Un Lee Kijun Seong Jiyong Park 《Journal of the science of food and agriculture》2012,92(15):2975-2982
BACKGROUND: The conventional method of processing ginseng (Panax ginseng) roots into red ginseng involves mainly heating and drying processes. In the present study, this method was modified by using high hydrostatic pressure (HHP) to improve the physicochemical characteristics of red ginseng. RESULTS: The HHP process (600 MPa for 1 min) significantly improved the histological properties of red ginseng by increasing cellular disruption and release of cell contents. The total reducing sugar content was significantly (P < 0.05) higher (increased from 10.67 to 15.25 mg g?1) in red ginseng processed at 600 MPa for 1 min. Similarly, the total free amino acid content also increased significantly (from 2.81 to 7.77 mg g?1). The HHP process resulted in superior and more even colouration and gave an attractive visual appearance to red ginseng. The optical density at 420 nm and Hunter's colour a value (redness) of extracts prepared from red ginseng increased significantly (P < 0.05) with the application of HHP. CONCLUSION: HHP‐processed red ginseng has significantly higher reducing sugar and free amino acid contents together with a more compact cell structure and superior visual quality (brighter red colour). Hence the application of HHP in red ginseng processing can result in ginseng products of improved quality compared with those obtained by the conventional method. Copyright © 2012 Society of Chemical Industry 相似文献
76.
精选白参经过超声波提取,得到人参提取物。蓝莓经过榨汁、喷雾干燥制成蓝莓果汁粉。以人参提取物和蓝莓果汁粉为主要原料,淀粉、木糖醇等为辅料,以40%乙醇作为润湿剂,经压片而制成的一种新型口嚼片。通过单因素和正交试验,确定最佳工艺条件和配方。结果表明,人参提取物添加量为15%、蓝莓果汁粉添加量35%、淀粉添加量为20%、40%乙醇添加量为40%。 相似文献
77.
Synthesis of flavonols and expression of flavonol synthase genes in the developing grape berries of Shiraz and Chardonnay (Vitis vinifera L.) 总被引:1,自引:0,他引:1
MARK O. DOWNEY JOHN S. HARVEY SIMON P. ROBINSON 《Australian Journal of Grape and Wine Research》2003,9(2):110-121
Flavonols were determined in Shiraz and Chardonnay grapes throughout berry development. The predominant flavonols were quercetin-3-glycosides with trace amounts of kaempferol-3-glycosides detected in Shiraz flowers but not in developing berries. Flavonols were present in the skin of ripening grapes but were not detected in seeds or flesh. Flavonols were also present in buds, tendrils, inflorescences, anthers and leaves. The concentration of flavonols in flowers (mg/g fresh weight) was high and decreased between flowering and berry set then remained relatively constant through berry development. The total amount of flavonols in berries (mg/berry) was low until pre-veraison then increased during berry development, particularly before veraison, the onset of ripening, in Chardonnay and during ripening in Shiraz. Two cDNA fragments with homology to genes encoding the enzyme flavonol synthase (FLS) were isolated from Shiraz flowers. In the overlapping region of the two cDNAs, they had 80% sequence identity at the nucleotide level and both had high homology to FLS genes from other plants. VvFLS1 was expressed in leaves, tendrils, pedicels, buds and inflorescences as well as in developing grapes. Expression was highest between flowering and fruit set then declined, increasing again during ripening coincident with the increase in flavonols per berry. Expression of VvFLS2 was much lower than for VvFLS1 and did not change during berry development. The results indicate that two distinct periods of flavonol synthesis occur in grapes, the first around flowering and the second during ripening of the developing berries. 相似文献
78.
79.
目的 探讨低温等离子体处理对鲜参切片表面微生物的杀菌效果,以及对鲜参切片表面色泽的影响,获得优化杀菌工艺条件,为鲜人参的保鲜贮藏提供新方法。方法 首先,以鲜参切片表面微生物的杀菌率为指标,考察放电电源功率(W)、等离子体处理时间(min)、气体流速(cm3/min)三个因素的杀菌效果,然后根据单因素试验的结果,应用三因素三水平响应面优化试验设计,获得最佳杀菌工艺,并测定低温等离子体处理鲜参切片的色泽变化。结果 低温等离子体处理鲜参切片的最佳杀菌工艺条件为:放电电源功率340 W、等离子体处理时间4.7 min、气体流速10 cm3/min,在此条件下的杀菌率为99.89%;影响因素的显著性大小顺序为: 等离子体处理时间>放电电源功率>气体流速,且鲜切参片经低温等离子体处理后色泽无明显变化。与酸性氧化电位水杀菌相比,低温等离子体处理的杀菌率提高了5.3%, 杀菌时间缩短了57%, 杀菌效果更好。结论:低温等离子体处理对鲜参切片表面微生物的杀菌效果显著,低温等离子体处理可以作为一种更高效、更省时的非热杀菌方法。 相似文献
80.
探究人参与大蒜混合发酵对黑参微生物多样性、成分以及生理功能的影响。以新鲜大蒜和人参为原料,采用液态发酵法自制黑蒜、黑参和参蒜,对其发酵过程中微生物多样性、主要成分以及抗氧化性进行分析。结果表明:参蒜产品的优势菌门为厚壁菌门,优势菌属为uncultured_bacterium_f_Muribaculaceae、乳杆菌属等;根据京都基因与基因组百科全书进行代谢途径预测,参蒜与大蒜和人参的代谢途径无明显差异,主要为全局及概要图、碳水化合物代谢和氨基酸代谢;参蒜的还原糖含量和总酚含量显著提高,总酸含量下降,稀有人参皂苷转化率显著提高,潜在有害物质5-羟甲基糠醛含量显著下降;参蒜具有良好的自由基清除能力。以上研究为参蒜产品的开发、促进黑参产业的发展提供理论依据。 相似文献