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61.
Shan  Mingqiu  Jiang  Yulan  Fu  Yuanyuan  Zhou  Yongyi  Lu  Zhihui  Yu  Sheng  Yan  Hui  Liu  Chanchan  Chen  Peidong  Bao  Beihua  Zhang  Li  Wu  Qinan 《Phytochemistry Reviews》2021,20(5):991-1012
Phytochemistry Reviews - Nepeta tenuifolia (N. tenuifolia) is a common aromatic herb that is widespread in East Asia. The aerial parts and spikes can be used as the traditional phytomedicines for...  相似文献   
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玉米作为主要的杂粮谷物,营养价值高,维生素、膳食纤维等含量丰富,可以预防多种亚健康疾病,受到市场追捧。但是玉米粉营养结构不均衡、加工性差,限制其应用。有研究表明,微生物发酵技术可以改善谷物的营养成分、大分子物质结构和加工特性。基于此,利用灵芝固态发酵玉米,得到玉米灵芝菌粮(简称菌粮),从营养成分、大分子物质结构和加工特性3个方面对其进行评价。结果显示,与未发酵玉米相比,菌粮中碳水化合物、蛋白质含量分别提高了748%、28.00%,且蛋白质的氨基酸评分提高,而脂肪含量降低了52.56%;维生素C、核黄素和烟酸含量均显著提高(P<0.05),分别提高了56.19%、73.91%和20.27%,且玉米中缺乏的硫胺素在菌粮中被检测到;菌粮中各类淀粉和纤维的含量也发生了显著变化(P<0.05),淀粉、支链淀粉含量分别降低了11.17%、34.70%,直链淀粉含量提高了26.66%,粗纤维、不溶性膳食纤维含量分别降低了21.07%、21.47%,可溶性膳食纤维含量提高了13.57%;菌粮粉粘度降低,水溶性指数提高,吸水性指数和溶胀力降低;此外,与灵芝子实体相比,菌粮中灵芝三萜和灵芝酸含量均显著提高(P<0.05),分别为灵芝子实体的1.68和2.07倍。灵芝固态发酵玉米得到的玉米灵芝菌粮,营养结构更加均衡,功能活性提高,具有更高的营养价值;大分子物质结构发生改变,加工特性得到改善,冲调特性更好。研究结果为食用菌发酵改良谷物特性的研究提供了参考和指导。  相似文献   
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Self‐interference is one of the most important selective forces in shaping floral evolution. Herkogamy and dichogamy both can achieve reductions in the extent of self‐interference, but they may have different roles in minimizing self‐interference in a single species. We used four self‐incompatible Epimedium species to explore the roles of herkogamy and dichogamy in avoiding self‐interference and to test the hypothesis that herkogamy and dichogamy may be separated and become selected preferentially in the taxa. Two species (Efranchetii and Emikinorii) expressed strong herkogamy and weak protogyny (adichogamy), whereas another two species (Esutchuenense and Eleptorrhizum) expressed slight herkogamy and partial protandry. Field investigations indicated that there was no physical self‐interference between male function and female function regarding pollen removal and pollen deposition in all species. Self‐pollination (autonomous or facilitated) was greater in species with slight herkogamy than in those with strong herkogamy. Artificial pollination treatments revealed that self‐pollination could reduce outcrossed female fertility in all species, and we found evidence that self‐interference reduced seed set in E. sutchuenense and E. leptorrhizum in the field, but not in E. franchetii and E. mikinorii. These results indicate that well‐developed herkogamy is more effective compared with dichogamy in avoiding self‐interference in the four species. In genus Epimedium, herkogamy instead of dichogamy should be selected preferentially and evolved as an effective mechanism for avoiding self‐interference and might not need to evolve linked with dichogamy.  相似文献   
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The conversion of soybean oil to biodiesel fuel was investigated in the presence of a lipase from Thermomyces lanuginosus (commercially called Lipozyme TL IM) in a solvent-free medium. The lipase was inactivated when more than 1.5 molar equivalent of methanol was added to the oil mixture. To fully convert the oil to its corresponding methyl esters, the reaction was performed successfully by a three-step addition of 1 molar equivalent of methanol and under the optimized conditions (40°C, 150 rpm, 10% enzyme quantity based on oil weight), the maximum methyl ester (ME) yield was 98% after 12 h reaction. By-product glycerol had a negative effect on enzymatic activity and iso-propanol was found to be effective for glycerol removal, in the presence of which lipase expressed relatively high activity and more than 94% of the ME yield was maintained after being used repeatedly for 15 batches.  相似文献   
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Altered expressions of receptor for advanced glycation end-products (RAGE) and its ligand (S100A9) are observed in many cancers and play a key role in inflammation-associated cancer. In our previous study, by two-dimensional gel electrophoresis followed by mass spectrometry, the expression of S100A9 protein was found to increase in squamous cervical cancer compared with adjacent normal cervical tissues. Therefore, in the present study we observed the expressions of S100A9 and RAGE in 30 chronic cervicitis, 50 cervical intraepithelial neoplasia (CIN), and 40 squamous cervical cancer (SCC) using immunohistochemical analysis and analyzed the differential expression and possible role of S100A9 and RAGE in cancer development. Immunohistochemical findings were as follows: the expressions of S100A9 and RAGE were demonstrated in chronic cervicitis, CIN, and SCC. Moreover, their expressions were gradually increasing as the tumor progressed. In SCC, the staining scores of S100A9 and RAGE were significantly higher in well-differentiated tumors compared to moderately and poorly differentiated tumors. The expression of S100A9 in epithelial cells exhibited a positive correlation to RAGE expression in chronic cervicitis, CIN, and SCC. There were no significant difference of S100A9 immunoreactivity in stromal cells among chronic cervicitis, CIN, and SCC. Moreover, there was no correlation between S100A9 immunoreactivity in stromal cells of SCC and clinicopathological parameters. Finally, double immunohistochemistry illustrated that RAGE and S100A9 co-express in SCC. In conclusion, RAGE binds its ligand (S100A9), which plays an important role in the development of SCC. In addition, the expressions of S100A9 and RAGE in SCC tumor cells were closely associated with histological differentiation.  相似文献   
67.
This study investigated the preparation of drug-loaded fibers using a modified coaxial electrospinning process, in which only unspinnable solvent was used as sheath fluid. With zein/ibuprofen (IBU) co-dissolving solution and N, N-dimethylformamide as core and sheath fluids, respectively, the drug-loaded zein fibers could be generated continuously and smoothly without any clogging of the spinneret. Field emission scanning electron microscopy and transmission electron microscopy observations demonstrated that the fibers had ribbon morphology with a smooth surface. Their average diameters were 0.94 ± 0.34 and 0.67 ± 0.21 μm when the sheath-to-core flow rate ratios were taken as 0.11 and 0.25, respectively. X-ray diffraction and differential scanning calorimetry verified that IBU was in an amorphous state in all fiber composites. Fourier transform infrared spectra showed that zein had good compatibility with IBU owing to hydrogen bonding. In vitro dissolution tests showed that all the fibers could provide sustained drug release files via a typical Fickian diffusion mechanism. The modified coaxial electrospinning process reported here can expand the capability of electrospinning in generating fibers and provides a new manner for developing novel drug delivery systems.KEYWORDS: coaxial electrospinning, drug-loaded fibers, sheath solvent, sustained release, zein  相似文献   
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Proline accumulation was often correlated with drought tolerance of plants infected by arbuscular mycorrhizal fungi (AMF), whereas lower proline in some AM plants including citrus was also found under drought stress and the relevant mechanisms have not been fully elaborated. In this study proline accumulation and activity of key enzymes relative to proline biosynthesis (▵1-pyrroline-5-carboxylate synthetase, P5CS; ornithine-δ-aminotransferase, OAT) and degradation (proline dehydrogenase, ProDH) were determined in trifoliate orange (Poncirus trifoliata, a widely used citrus rootstock) inoculated with or without Funneliformis mosseae and under well-watered (WW) or water deficit (WD). AMF colonization significantly increased plant height, stem diameter, leaf number, root volume, biomass production of both leaves and roots and leaf relative water content, irrespectively of water status. Water deficit induced more tissue proline accumulation, in company with an increase of P5CS activity, but a decrease of OAT and ProDH activity, no matter whether under AM or no-AM. Compared with no-AM treatment, AM treatment resulted in lower proline concentration and content in leaf, root, and total plant under both WW and WD. The AMF colonization significantly decreased the activity of both P5CS and OAT in leaf, root, and total plant under WW and WD, except for an insignificant difference of root OAT under WD. The AMF inoculation also generally increased tissue ProDH activity under WW and WD. Plant proline content significantly positively correlated with plant P5CS activity, negatively with plant ProDH activity, but not with plant OAT activity. These results suggest that AM plants may suffer less from WD, thereby inducing lower proline accumulation, which derives from the integration of an inhibition of proline synthesis with an enhancement of proline degradation.  相似文献   
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