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81.
Several modern drugs, which are derived from traditional herbal medicine are used in contemporary pharmacotherapy. Currently, the study of drug–plant interactions in pain has increased in recent years, looking for greater efficacy of the drug and reduce side effects. The antinociception induced by intragastric co-administration of the combination of pomegranate peel extract (PoPEx) and acetylsalicylic acid (ASA) was assessed using the isobolographic analysis in formalin test (nociceptive and inflammatory pain). The effective dose that produced 30% of antinociception (ED30) was calculated for both drugs from the logarithmic dose–response curves, subsequently generating a curve with the combination on fixed proportions (1:1) of PoPEx and ASA. Through isobolographic analysis, this experimental ED30 was compared with the calculated theoretical additive ED30. The result was a synergistic interaction, the experimental ED30 was significantly smaller (p < 0.05) than the theoretical ED30. The antinociceptive mechanism of the PoPEx-ASA combination involves the l-Arginine/NO/cGMP pathway, antioxidant capacity, and high content of total phenols. These findings suggest that an interaction between PoPEx and ASA could be a novel treatment for inflammatory and nociceptive pain, also diminish the secondary reactions of ASA.  相似文献   
82.
大孔吸附树脂法柚皮果胶脱色工艺研究   总被引:13,自引:0,他引:13  
比较了AB-8、S-8、X-5、聚酰胺、NKA-Ⅱ、NPD-600等6种大孔吸附树脂对柚皮果胶的脱色效果.在静态吸附试验研究的基础上,筛选出效果较好的树脂进行动态试验研究.实验表明:AB-8型大孔吸附树脂对柚皮果胶提取液具有较好的吸附脱色效果和较低的果胶损失率,该树脂对柚皮果胶脱色的适宜工艺参数为:室温(约20℃),流速3BV/h,溶液处理量为5BV,上柱液pH值为4~6.此工艺对果胶提取液中色素的吸附率约80%.树脂吸附后可用70%乙醇进行洗涤再生,果胶提取液脱色后经喷雾干燥所得的果胶成品质量符合QB2484-2000标准.  相似文献   
83.
Pomelo peel waste-derived porous carbon (PPPC) was prepared by a facile one-step ZnCl2 activation method. The preparation parameters of PPPC were the mass ratio of ZnCl2 to pomelo peel of 2:1, carbonization temperature of 500 °C, and carbonization time of 1 h. This obtained PPPC possessed abundant macro-,meso-, and micro-porous structures, and a large specific surface area of 939.4 m2 g−1. Surprisingly, it had excellent adsorption ability for methylene blue, including a high adsorption capacity of 602.4 mg g−1 and good reusability. The adsorption isotherm and kinetic fitted with Langmuir and pseudo-second order kinetic models. This work provides a novel strategy for pomelo peel waste utilization and a potential adsorbent for treating dye wastewater.  相似文献   
84.
DRIFT, HPLC-MS, and SPME-GC/MS analyses were used to unveil the structure and the main functional compounds of red (blood) orange (Citrus sinensis) and bitter orange (Citrus aurantium). The IntegroPectin samples show evidence that these new citrus pectins are comprised of pectin rich in RG-I hairy regions functionalized with citrus biophenols, chiefly flavonoids and volatile molecules, mostly terpenes. Remarkably, IntegroPectin from the peel of fresh bitter oranges is the first high methoxyl citrus pectin extracted via hydrodynamic cavitation, whereas the red orange IntegroPectin is a low methoxyl pectin. C. aurantium IntegroPectin has a uniquely high concentration of adsorbed flavonoids, especially the flavanone glycosides hesperidin, naringin, and eriocitrin.  相似文献   
85.
86.
Citrus bioflavonoids are polyphenolic plant-derived pigments found in high levels in oranges, lemons, grapefruits and other citrus fruits. The three most abundant types of citrus bioflavonoids are hesperidin, naringenin and eriocitrin. Citrus bioflavonoids have long been known to possess powerful free radical-scavenging properties and cardioprotective effects. The study involved the analysis of 10 commercially available citrus bioflavonoid supplements from three different countries: Australia, the United States and Canada. The supplements were tested for their citrus bioflavonoid content which varied from 0.8 to 33.3% w/w. The daily bioflavonoid dose varied from 19 mg to 560 mg. Hesperidin was the major citrus bioflavonoid in nine out of ten supplements. One supplement was found to contain less than 10% of the quantity of rutin claimed to have been added. The DPP-4 inhibitory potential, compared through an estimation of rutin equivalence, ranged from 1.9 mg to 400 mg per day. This data highlights the variability between the supplements in their potential to inhibit DPP-4 for subsequent health benefits.  相似文献   
87.
Verbenone and carvone are allylic monoterpenoid ketones with many applications in the fine chemicals industry that can be obtained, respectively, from the allylic oxidation of α-pinene and limonene over a silica-supported iron hexadecachlorinated phthalocyanine (FePcCl16-NH2-SiO2) catalyst and with t-butyl hydroperoxide (TBHP) as oxidant. As there are no reported analyses of the environmental impacts associated with catalytic transformation of terpenes into value-added products that include the steps associated with synthesis of the catalyst and several options of raw materials in the process, this contribution reports the evaluation of the environmental impacts in the conceptual process to produce verbenone and carvone considering two scenarios (SI-raw-oils and SII-purified-oils). The impact categories were evaluated using ReCiPe and IPCC methods implemented in SimaPro 9.3 software. The environmental impacts in the synthesis of the heterogeneous catalyst FePcCl16-NH2-SiO2 showed that the highest burdens in terms of environmental impact come from the use of fossil fuel energy sources and solvents, which primarily affect human health. The most significant environmental impacts associated with carvone and verbenone production are global warming and fine particulate matter formation, with fewer environmental impacts associated with the process that starts directly from turpentine and orange oils (SI-raw-oils) instead of the previously extracted α-pinene and limonene (SII-purified-oils). As TBHP was identified as a hotspot in the production process of verbenone and carvone, it is necessary to choose a more environmentally friendly and energy-efficient oxidizing agent for the oxidation of turpentine and orange oils.  相似文献   
88.
Pectin is an acidic heteropolysaccharide found in the cell walls and the primary and middle lamella of land plants. To be authorized as a food additive, industrial pectins must meet strict guidelines set forth by the Food and Agricultural Organization and must contain at least 65% polygalacturonic acid to achieve the E440 level. Fruit pectin derived from oranges or apples is commonly used in the food industry to gel or thicken foods and to stabilize acid-based milk beverages. It is a naturally occurring component and can be ingested by dietary consumption of fruit and vegetables. Preventing long-term chronic diseases like diabetes and heart disease is an important role of dietary carbohydrates. Colon and breast cancer are among the diseases for which data suggest that modified pectin (MP), specifically modified citrus pectin (MCP), has beneficial effects on the development and spread of malignancies, in addition to its benefits as a soluble dietary fiber. Cellular and animal studies and human clinical trials have provided corroborating data. Although pectin has many diverse functional qualities, this review focuses on various modifications used to develop MP and its benefits for cancer prevention, bioavailability, clinical trials, and toxicity studies. This review concludes that pectin has anti-cancer characteristics that have been found to inhibit tumor development and proliferation in a wide variety of cancer cells. Nevertheless, further clinical and basic research is required to confirm the chemopreventive or therapeutic role of specific dietary carbohydrate molecules.  相似文献   
89.
Biodegradable pH‐responsive polysuccinimide nanoparticles (PSI‐NPs) are synthesized for directly delivering agrochemicals to plant phloem to improve their efficacy. The PSI‐NPs have an average size of 20.6 nm with negative charge on the surface. The desired responsiveness to changes in pH is demonstrated by release efficiency of the model molecule (Coumarin 6), which increases with increasing pH over 24 h. The internalization of PSI‐NPs into grapefruit cells occurs in 10 min, and into nucleus in 2 h, with most of the PSI‐NPs being distributed in cytoplasm and nucleus. The proportion of PSI‐NPs in plant cells significantly increases with time, from 19.1% at 10 min to 55.5% at 2 h of administering. The PSI‐NPs do not show significant inhibitory effects on soil microbial growth and activity. These results indicate that this smart nanodelivery system has potential of application in agriculture for mitigating phloem‐limited diseases, such as citrus huanglongbing.  相似文献   
90.
白云母的剥片及粉碎技术   总被引:1,自引:0,他引:1  
本文在分析白云母结构特点的基础上,阐述了白云母的剥片及粉碎技术,并介绍了所研制的研磨机及样品试验对比结果.  相似文献   
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