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11.
The effects of boiling and steaming processes on the antiproliferative and cellular antioxidant properties, as well as phytochemicals, of two types of common beans (pinto and black beans) and two types of soybeans (yellow and black) were investigated. All thermal-processing methods caused significant (< 0.05) decreases in total phenolic content (TPC), total saponin content (TSC) and phytic acid content (PAC) values in all bean types (except for TPC values in pressure-steamed yellow soybeans) as compared to those of the raw beans. All types of uncooked raw beans exhibited cellular antioxidant activities (CAA) in dose-dependent manners. Black soybeans exhibited the greatest CAA, followed by black beans, pinto beans and yellow soybeans. The CAA of cooked beans were generally diminished or eliminated by thermal processing. The hydrophilic extracts from raw pinto beans, black beans and black soybeans exhibited antiproliferation capacities against human gastric (AGS) and colorectal (SW480) cancer cells in dose-dependent manners. The raw yellow soybeans exhibited dose-dependent antiproliferation activities against the SW480 cells. Most of the cooked beans lost their antiproliferation capacities as observed in the raw beans. These results indicate that different processing methods may have various effects on phytochemical profiles and bioactivities. Overall, thermal processing caused a significant reduction of the health-promotion effects of beans.  相似文献   
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Chitosan–silver nanocomposites (CS-HDA-AgNCs) was prepared using chitosan, biogenic silver nanocomposites, and crosslinker, hexamethylene 1,6-di(amino carboxysulfonate) (HDA). The film is flexible and transparent. Its physical, mechanical, thermal, hydrophilicity, and swelling properties were improved by HDA (2.5%). The antimicrobial activity of CS-HDA-AgNCs were not displayed any remarkable zone of inhibition but showed toxic effect in the presence of normal 3T3 fibroblasts and cancer HeLa cells. It decreases to ca. 5–7% for both cell lines. In conclusion, it can be mentioned that the CS-HDA-AgNCs, a kind of new functional biomaterial, could be useful for health-care applications.  相似文献   
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程翠林  王荣春  杨雨茗  杨慧勤  卢卫红 《精细化工》2020,37(11):2308-2312,2341
本文首次研究了一种半合成香叶木苷的化学方法,并测定该合成产物对六种常见癌细胞的抗增殖活性。该方法以廉价的橙皮苷为原料,用DDQ作脱氢剂,氧化制备香叶木苷。经sephadex LH-20柱纯化后,HPLC-MS与1H-NMR鉴定确定该产物为香叶木苷,首次证实该转化方法对于黄酮苷类物质的合成是可行的。优化所得合成工艺为:原料质量比为1:0.4,反应温度为110℃(油浴温度),反应时间为6小时。本实验的研究结果为香叶木苷的合成与应用提供新的途径。  相似文献   
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A powdered mixture of dried herbs, “Panamrutham”, is sold in India for the preparation of “herbal drinking water”. The hot water extract of this herbal mixture gave lipid peroxidation (LPO), cyclo‐oxygenase (COX‐1 and ‐2) enzyme and human tumor cell proliferation inhibitory activities between 25 and 250 μg/mL. The bioassay‐guided purification of the water extract afforded a novel compound (1), along with phenolics (2, 4, 6, and 7) and sesquiterpenoids (3 and 5). The isolates were evaluated for LPO, COX‐1 and ‐2 enzyme and human tumor cell proliferation inhibitory activities. At 25 μg/mL, compounds 1–7 inhibited LPO by 22–73% and COX‐1 and ‐2 enzymes by 3–14% and 14–74%, respectively. Compounds 5 and 6 at 25 μg/mL showed growth inhibition of colon, gastric, lung, breast and central nervous system human tumor cell lines by 60 and 67, 43 and 60, 24 and 64, 34 and 65, 6 and 27%, respectively. Compounds 2, 4 and 7 displayed weak or moderate growth inhibition of colon, gastric and breast human tumor cell lines. This is the first report on the LPO inhibitory activities of compounds 1 and 3–7 and the COX and tumor cell proliferation inhibitory activities of compounds 1, 3–5 and 7.  相似文献   
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Devil’s club (Oplopanax horridus (Sm.) Miq.) has traditionally been used as a folk medicine by native North Americans for the treatment of various chronic diseases. A methanolic extract and its sub-fractions by liquid–liquid re-extraction, i.e., chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (BuOH), and water fractions, were analysed by their anti-cancer activity with in vitro cell proliferative bioassays, and their antioxidant capacities in terms of the determination of total phenolic content (TPC), ORAC value, and DPPH free radical scavenging activity. The whole extract of the dried root contained high TPC and possessed strong ORAC and DPPH radical scavenging activities. In addition, the extract exhibited a strong anti-proliferative ability against HT-29 cancer cells, e.g., with an inhibitive rate of 56.5% with a 0.2-mg/mL extract. Further investigation by HPLC–UV–MS identified significant bioactive phenolic compounds in the chloroform fraction, including gallic acid, caffeic acid, 4-O-feruloylquinic acid, 5-O-feruloylquinic acid, ferulic acid, methyl feruloylquinate, methyl ferulate, and quercetin. These results suggested that the associated bioactivity of the plant might result from the contribution of phenolic compounds.  相似文献   
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Bacillus subtilis CSY191, the potential probiotics and surfactin-like compound producer, was isolated from doenjang (Korean traditional fermented soybean paste).The survival rate of this strain appeared to be the 58.3% under artificial gastric conditions after 3 h at pH 3.0. Surfactin was purified from the strain CSY191. Three potential surfactin isoforms were detected, with protonated masses of m/z 1030.7, 1044.7, and 1058.71. These different structures were detected in combination with Na+, K+ and Ca2+ ions by MALDI-TOF mass spectrometry. Upon 500 MHz 1H NMR analysis, the surfactin isoforms had identical amino acids (GLLVDLL) and hydroxy fatty acids (of 13-15 carbons in length). The MTT assay showed that surfactin inhibited growth of MCF-7 human breast cancer cells in a dose-dependent manner, with an IC50 of approximately 10 μg/ml at 24 h. Additionally, the surfactin contents, during cheonggukjang fermentation with strain CSY191, increased from 0.3 to 48.2 mg/kg over 48 h of fermentation, while the level of anticancer activity increased from 2.6- to 5.1-fold.  相似文献   
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There is a paucity of studies on the immunomodulatory properties of fruit extracts of emblica with the emphasis on lymphocytes. Therefore, the aim of the study was to evaluate the immunomodulatory properties and anticancer potential of six phenolic compounds from emblica fruit by in vitro proliferation assay. Effects of these compounds on splenocyte proliferation and the cytotoxicity to both human breast cancer cell (MCF-7) and human embryonic lung fibroblast cell (HELF) were determined by the MTT method. Significantly stimulatory effects (P < 0.05) were found for geraniin and isocorilagin. The concentration of geraniin, quercetin 3-β-d-glucopyranoside, kaempferol 3-β-d-glucopyranoside, isocorilagin, quercetin, kaempferol and rutin to obtain 50% of stimulatory effect was 56, 123, 242, 42, 73, 93 and 92 μg/ml, respectively. The assay of anticancer activities suggested that geraniin and isocorilagin exhibited higher cytotoxicities than other compounds against MCF-7 with IC50 of 13.2 and 80.9 μg/ml, respectively. Isocorilagin exhibited a strong cytotoxicity to HELF cell with IC50 of 51.4 μg/ml. Geraniin, quercetin, kaempferol and their glycosides had weak cytotoxicity against HELF cells. Paclitaxel showed a strong cytotoxicity to MCF-7 and HELF with IC50 of 6.8 and 14.5 μg/ml, respectively. These findings are in line with the reported potent antioxidant activity. These results suggested that the antitumour activity of these compounds might be achieved by immunomodulatory properties which could partially be attributed to their antioxidant activity.  相似文献   
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低温辐射聚合制备慢释放抗癌药物的研究   总被引:4,自引:4,他引:0  
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